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C620机床机械系统的经济型数控化改造探析外文文献翻译、中英文翻译

C620机床机械系统的经济型数控化改造探析外文文献翻译、中英文翻译

附录Analysis on the economic CNC transformation of machine system ofC620 machine toolLi YeThis paper briefly introduces the design scheme of nc transformation of machine system of C620 lathe. Compared with the purchase of new machine tools, the modified C620 lathe saves a lot of money and shortens the delivery time.Keywords: C620 lathe; Numerical control transformationJust now, China's machine tool equipment nc manufacturing equipment rate of less than 30%, and a large part of the structure problems, such as aging, idle or eliminated, all depend on the purchase of new CNC machine, and it can take huge sums of money to buy for the old machine is not reasonable use is also a kind of resource waste, this is obviously not conform to China's national conditions. Therefore, using digital technology to transform existing machine tools is a national need, industrial policy and feasible way. This paper makes a brief discussion on the economic CNC transformation of the machine system of C620 lathe.1. Modification scheme of mechanical system1.1 modification scheme of the main drive systemThe main role of spindle is to be responsible for the accuracy of nc machine tools, is a very important component. The frequency conversion speed of ac asynchronous motor is increased on the spindle, and the machining precision is improved. CNC lathe modification with different shaft installation, in the numerical control lathe spindle is installed on a spindle pulse encoder, for in the thread machining, prevent coaxial when machining parts can't wear a lathe spindle hole. Due to the different axis installation will show the location of the main shaft signal, so, when install, pay special attention to the main shaft axis and the derivation of the lathe spindle pulse encoder to achieve zero clearance between flexible coupling transmission (the ratio of 1:1), synchronous tooth profile can be very good to do this. The spindle of a lathe is limited in the process of using it. The maximum speed of a driving shaft pulse generator is subject to the highest speed limit, which cannot exceed its maximum speed.Pulse encoder connection way, complete the following steps: ac spindle motor through the pulley movement to the spindle, the spindle movement through synchronous pulley and synchronous belt wheel 2 and 1 synchronous belt drive pulse encoder, with spindle speed operation, pulse encoder on the spindle box body with screws.Generally, in the transformation of horizontal lathe numerical control, the amount of work of mechanical transformation is large, and the main drive and variable speed control mechanism on the machine tool can be retained, which can greatly reduce the amount of work. The forward and reverse rotation and stop functions of the spindle can be controlled by a numerical control system. Single-speed motor can be replaced by 2-4 speed multi-speed motor. The control of multi-speed motor can be realized by using ac inverter by spindle motor, which can meet the requirement of stepless variable speed. Through actual operation, it is proved that in the process of operating the converter, if the operating frequency of the original motor is below 70HZ, no replacement is required, but the power of the converter is greater than that of the motor.The above example, when to have a variable can use the YD series level 7.5 kw variable multispeed three-phase asynchronous motor, this machine produced by zhejiang chaoli motor co., LTD.) for 2 ~ 4 block variable speed; The precondition of adopting the stepless variable speed is to install ac frequency converter. It is recommended to use the model f1000-g0075t3b produced by yantai huifeng electronics co., LTD., with a 7.5kw motor.1.2 replace the automatic rotary tool holderCan help to improve nc machining precision machine tool and can be done a one-time multi-channel working procedure, its model for LD4B - CK6140 four station vertical electric tool rest is a good equipment and the choice, the device production and changzhou hongda nc equipment co., LTD., can be very good to complete the manual tool post transfer automatic rotary tool rest. And the nc system can help the automatic tool change when the circuit configuration requirements.1.3 installation scheme of screw encoderScrew encoder, also known as spindle pulse generator or circular grating. When threading, the CNC lathe should install the spindle pulse generator to feedback the position of the spindle of the lathe and rotate synchronously with the spindle of the lathe. Examples are given below.Reformed lathe, can lead most no more than 24 mm thread processing, Z to feed is 0.01 mm/pulse,each thread encoder, cannot be less than 24 mm (0.01 mm pulse - 1) = 2400 pulse output. Because the output of the encoder is different (phase difference is 900 A, B believe signal), A and B can be logically different or obtain 2,400 pulses. In this way, the number of lines in the pulse encoder can be reduced to 1200 lines (A and B signals). Also note that the encoder also needs to output a zero - bit pulse Z for each turn to repeat the same spiral groove.According to the above requirements, the following examples are selected as the screw encoder of model zlf-1200z-05v0-150ct, which is from changchun optical machine digital display technology co., LTD. The power supply voltage is +5V, with 1200 A/B pulses and 1 Z pulse for each output. The signal is voltage output and the shaft head diameter is 15mm.In threaded code installation, common installation methods are coaxial and cross-axis installation. Coaxial installation means that the encoder is installed directly on the spindle and coaxial with the spindle. Although this method is fast and simple, it has the disadvantage of easily causing the blockage of the main shaft through hole. Off-axis installation, namely in the back of the spindle box installed encoder, best location on the main shaft synchronous rotating output shaft, such as there is no synchronous spindle axis, you can use synchronous cog belt and spindle joins (rotation ratio is 1:1). At this time, the shaft head of the encoder must be connected with the installation shaft without clearance, which is a point needing attention, and the maximum speed of the spindle should be controlled within the maximum allowable speed of the encoder.1.4 modification and design scheme of feed systemThe pulse instructions issued by the nc system are received and amplified and converted by the feed system of the nc machine tool. The lateral (X axis) movement of the tool holder is driven by the horizontal feed drive system, which controls the radial dimension of the workpiece. The axial (Z axis) motion is driven by the longitudinal feed device, which controls the axial dimensions of the workpiece.1.4.1 feed drive chainTransverse feed (X axis) consists of stepper motor and reducer drive (stepper motor is installed behind the bed saddle), feed drive system include: stepper motor, vertical screw pair, synchronous belt, horizontal screw pair.1.4.2 selection of ball screw nut pairsTo ensure the machining accuracy of nc machine tools high, the requirements of the feed drivesystem with high transmission precision, high sensitivity, fast response), stable work, have a high stiffness of components and service life, small friction and inertia, and can remove the transmission clearance.1.4.3 design scheme process(1) remove all the gears on the hanging wheel, find out the synchronous shaft of the spindle, and install the screw encoder.(2) first remove the feed box assembly, and install the longitudinal stepping motor and synchronous belt reducer assembly (to be installed in the original position).(3) first remove the quick tool gear rack and slide box assembly, and then install the nut holder bracket of the longitudinal ball screw (to be installed under the bed saddle).(4) first remove the square tool holder and small skateboard assembly, and then install the four-station vertical electric knife holder above the middle skateboard.(5) to dismantle the skateboard sliding screw nut pair, sawing the roller screw in dial a long (216 mm) and reserves, will the handles on the dial down, while retaining the dial nearby two thrust bearing, finally the ball screw pair of change.(6) install the horizontal feed stepping motor on the bed saddle at the back of the middle skateboard through the flange seat and connect it with the shaft head of the ball screw.(7) remove the parallel bars (screw, light bar and joystick) and replace the right bearing of the parallel bars.2. ConclusionWe compared the mechanical system of a C620 lathe used in the production training with the newly purchased machine tool after the numerical control transformation, and the transformation cost was reduced by 60% to 80%, which was very economical. Especially in large, special machine tools especially prominent. The cost of large-scale machine tool transformation is only 1/3 of the total cost of newly purchased machine tool, and the delivery time is short.reference[1] Chen weidong, machinery processing equipment [M], Beijing university press, 2010.This article is from Silicon Valley, article number: 1671-7597 (2014) 15-0146-01C620机床机械系统的经济型数控化改造探析李烨摘要简要介绍C620车床的机械系统进行数控化改造的设计方案。

机械类数控外文翻译外文文献英文文献数控.doc

机械类数控外文翻译外文文献英文文献数控.doc

Numerical ControlOne of the most fundamental concepts in the area of advanced manufacturing technologies is numerical control (NC).Prior to the advent of NC, all machine tools were manual operated and controlled. Among the many limitations associated with manual control machine tools, perhaps none is more prominent than the limitation of operator skills. With manual control, the quality of the product is directly related to and limited to the skills of the operator . Numerical control represents the first major step away from human control of machine tools.Numerical control means the control of machine tools and other manufacturing systems though the use of prerecorded, written symbolic instructions. Rather than operating a machine tool, an NC technician writes a program that issues operational instructions to the machine tool, For a machine tool to be numerically controlled , it must be interfaced with a device for accepting and decoding the p2ogrammed instructions, known as a reader.Numerical control was developed to overcome the limitation of human operator , and it has done so . Numerical control machines are more accurate than manually operated machines , they can produce parts more uniformly , they are faster, and the long-run tooling costs are lower . The development of NC led to the development of several other innovations in manufacturing technology:1.Electrical discharge machining.ser cutting.3.Electron beam welding.Numerical control has also made machine tools more versatile than their manually operated predecessors. An NC machine tool can automatically produce a wide variety of par4s , each involving an assortment of undertake the production of products that would not have been feasible from an economic perspective using manually controlled machine tools and processes.Like so many advanced technologies , NC was born in the laboratories of the Massachusetts Institute of Technology . The concept of NC was developed in the early 1950s with funding provided by the U.S Air Force .In its earliest stages , NC machines were able to make straight cuts efficiently and effectively.However ,curved paths were a problem because the machine tool had to be programmed to undertake a series of horizontal and vertical steps to produce a curve. The shorter is the straight lines making up the step ,the smoother is 4he curve . Each line segment in the steps had to be calculated.This problem led to the development in 1959 of the Automatically Programmed Tools (APT) language for NC that uses statements similar to English language to define the part geometry, describe the cutting tool configuration, and specify the necessary motions. The development of the APT language was a major step forward in the further development of NC technology. The original NC system were vastly different from those used punched paper , which was later to replaced by magnetic plastic tape .A tape reader was used to interpret the instructions written on the tape for the machine .Together, all /f this represented giant step forward in the control of machine tools . However ,there were a number of problems with NC at this point in its development.A major problem was the fragility of the punched paper tape medium . It was common for the paper containing the programmed instructions to break or tear during a machining process, This problem was exacerbated by the fact that each successive time a part was produced on a machine tool, the paper tape carrying the programmed instructions had to rerun thought the reader . If it was necessary to produce 100 copies of a given part , it was also necessary to run the paper tape thought the reader 100 separate times . Fragile paper tapes simply could not withstand the rigors of shop floor environment and this kind of repeated use.This led to the development of a special magnetic tape . Whereas the paper tape carried the programmed instructions as a series of holes punched in the tape , theThis most important of these was that it was difficult or impossible to change the instructions entered on the tape . To make even the most minor adjustments in a program of instructions, it was necessary to interrupt machining operations and make a new tape. It was also still necessary to run the tape thought the reader as many times as there were parts to be produced . Fortunately, computer technology become a reality and soon solved the problems of NC, associated with punched paper and plastic tape.The development of a concept known as numerical control (DNC) solve the paper and plastic tape problems associated with numerical control by simply eliminating tape as the medium for carrying the programmed instructions . In direct numerical control, machine tools are tied, via a data transmission link, to a host computer and fed to the machine tool as needed via the data transmission linkage. Direct numerical control represented a major step forward over punched tape and plastic tape. However ,it is subject to the same limitation as all technologies that depend on a host computer. When the host computer goes down , the machine tools also experience down time . This problem led to the development of computer numerical control.The development of the microprocessor allowed for the development of programmable logic controllers (PLC) and microcomputers . These two technologies allowed for the development of computer numerical control (CNC).With CNC , each machine tool has a PLC or a microcomputer that serves the same purpose. This allows programs to be input and stored at each individual machine tool. CNC solved the problems associated downtime of the host computer , but it introduced another problem known as data management . The same program might be loaded on ten different microcomputers with no communication among them. This problem is in the process of being solved by local area networks that connectDigital Signal ProcessorsThere are numerous situations where analog signals to be processed in many ways, like filtering and spectral analysis , Designing analog hardware to perform these functions is possible but has become less and practical, due to increased performance requirements, flexibility needs , and the need to cut down on development/testing time .It is in other words difficult pm design analog hardware analysis of signals.The act of sampling an signal into thehat are specialised for embedded signal processing operations , and such a processor is called a DSP, which stands for Digital Signal Processor . Today there are hundreds of DSP families from as many manufacturers, each one designed for a particular price/performance/usage group. Many of the largest manufacturers, like Texas Instruments and Motorola, offer both specialised DSP’s for certain fields like motor-control or modems ,and general high-performance DSP’s that can perform broad ranges of processingtasks. Development kits an` software are also available , and there are companies making software development tools for DSP’s that allows the programmer to implement complex processing algorithms using simple “drag ‘n’ drop” methodologies.DSP’s more or less fall into t wo categories depending on the underlying architecture-fixed-point and floating-point. The fixed-point devices generally operate on 16-bit words, while the floating-point devices operate on 32-40 bits floating-point words. Needless to say , the fixed-point devices are generally cheaper . Another important architectural difference is that fixed-point processors tend to have an accumulator architecture, with only one “general purpose” register , making them quite tricky to program and more importantly ,making C-compilers inherently inefficient. Floating-point DSP’s behave more like common general-purpose CPU’s ,with register-files.There are thousands of different DSP’s on the market, and it is difficult task finding the most suitable DSP for a project. The best way is probably to set up a constraint and wishlist, and try to compare the processors from the biggest manufacturers against it.The “big four” manufacturers of DSPs: Texas Instruments, Motorola, AT&T and Analog Devices.Digital-to-analog conversionIn the case of MPEG-Audio decoding , digital compressed data is fed into the DSP which performs the decoding , then the decoded samples have to be converted back into the analog domain , and the resulting signal fed an amplifier or similar audio equipment . This digital to analog conversion (DCA) is performed by a circuit with the same name & Different DCA’s provide different performance and quality , as measured by THD (Total harmonic distortion ), number of bits, linearity , speed, filter characteristics and other things.The TMS320 family DQP of Texas InstrumentsThe TLS320family consists of fixed-point, floating-point, multiprocessor digital signal processors (D[Ps) , and foxed-point DSP controllers. TMS320 DSP have an architecture designed specifically for real-time signal processing . The’ F/C240 is a number of the’C2000DSP platform , and is optimized for control applications. The’C24x series of DSP controllers combines this real-time processing capability with controller peripherals to create an ideal solution for control system applications. The following characteristics make the TMS320 family the right choice for a wide range of processing applications:--- Very flexible instruction set--- Inherent operational flexibility---High-speed performance---Innovative parallel architecture---Cost effectivenessDevices within a generation of the TMS320 family have the same CPU structure but different on-chip memory and peripheral configurations. Spin-off devices use new combinations of On-chip memory and peripherals to satisfy a wide range of needs in the worldwide electronics market. By integrating memory and peripherals onto a single chip , TMS320 devices reduce system costs and save circuit board space.The 16-bit ,fixed-point DSP core of the ‘C24x devices provides analog designers a digital solution that does not sacrifice the precision and performance of their system performance can be enhanced through the use of advanced control algorithms for techniquessuch as adaptive control , Kalman filtering , and state control. The ‘C24x DSP controller offer reliability and programmability . Analog control systems, on the other hand ,are hardwired solutions and can experience performance degradation due to aging , component tolerance, and drift.The high-speed central processing unit (CPU) allows the digital designer to process algorithms in real time rather than approximate results with look-up tables. The instruction set of these DSP controllers, which incorporates both signal processing instructions and general-purpose control functions, coupled with the extensive development time and provides the same ease of use as traditional 8-and 16-bit microcontrollers. The instruction set also allows you to retain your software investment when moving from other general-purp ose‘C2xx generation ,source code compatible with the’C2x generation , and upwardly source code compatible with the ‘C5x generation of DSPs from Texas Instruments.The ‘C24x architecture is also well-suited for processing control signals. It uses a 16-bit word length along with 32-bit registers for storing intermediate results, and has two hardware shifters available to scale numbers independently of the CPU . This combination minimizes quantization and truncation errors, and increases p2ocessing power for additional functions. Such functions might include a notch filter that could cancel mechanical resonances in a system or an estimation technique that could eliminate state sensors in a system.The ‘C24xDSP controllers take advantage of an set of peripheral functions that allow Texas Instruments to quickly configure various series members for different price/ performance points or for application optimization.This library of both digital and mixed-signal peripherals includes:---Timers---Serial communications ports (SCI,SPI)---Analog-to-digital converters(ADC)---Event manager---System protection, such as low-voltage and watchdog timerThe DSP controller peripheral library is continually growing and changing to suit the of tomorrow’s embedded control marke tplace.The TMS320F/C240 is the first standard device introduced in the ‘24x series of DSP controllers. It sets the standard for a single-chip digital motor controller. The ‘240 can execute 20 MIPS. Almost all instructions are executed in a simple cycle of 50 ns . This high performance allows real-time execution of very comple8 control algorithms, such as adaptive control and Kalman filters. Very high sampling rates can also be used to minimize loop delays.The ‘ 240 has the architectural features necessary for high-speed signal processing and digital control functions, and it has the peripherals needed to provide a single-chip solution for motor control applications. The ‘240 is manufactured using submicron CMOS technology, achieving a log power dissipation rating . Also included are several power-down modes for further power savings. Some applications that benefit from the advanced processing power of the ‘240 include:---Industrial motor drives---Power inverters and controllers---Automotive systems, such as electronic power steering , antilock brakes, and climatecontrol---Appliance and HV AC blower/ compressor motor controls---Printers, copiers, and other office products---Tape drives, magnetic optical drives, and other mass storage products---Robotic and CNC milling machinesTo function as a system manager, a DSP must have robust on-chip I/O and other peripherals. The event manager of the ‘240 is unlike any other available on a DSP . This application-optimized peripheral unit , coupled with the high performance DSP core, enables the use of advanced control techniques for high-precision and high-efficiency full variable-speed control of all motor types. Include in the event manager are special pulse-width modulation (PWM) generation functions, such as a programmable dead-band function and a space vector PWM state machine for 3-phase motors that provides state-of-the-art maximum efficiency in the switching of power transistors.There independent up down timers, each with it’s own compare register, suppo rt the generation of asymmetric (noncentered) as well as symmetric (centered) PWM waveforms.Open-Loop and Closed-Loop ControlOpen-loop Control SystemsThe word automatic implies that there is a certain amount of sophistication in the control system. By automatic, it generally means That the system is usually capable of adapting to a variety of operating conditions and is able to respond to a class of inputs satisfactorily . However , not any type of control system has the automatic feature. Usually , the automatic feature is achieved by feed.g the feedback structure, it is called an open-loop system , which is the simplest and most economical type of control system.inaccuracy lies in the fact that one may not know the exact characteristics of the further ,which has a definite bearing on the indoor temperature. This alco points to an important disadvantage of the performance of an open -loop control system, in that the system is not capable of adapting to variations in environmental conitions or to external disturbances. In the case of the furnace control, perhaps an experienced person can provide control for a certain desired temperature in the house; but id the doors or windows are opened or closed intermittently during the operating period, the final temperature inside the house will not be accurately regulated by the open-loop control.An electric washing machine is another typical example of an open-loop system , because the amount of wash time is entirely determined by the judgment and estimation of the human operator . A true automatic electric washing machine should have the means of checking the cleanliness of the clothes continuously and turn itsedt off when the desired degised of cleanliness is reached.Closed-Loop Control SystemsWhat is missing in the open-loop control system for more accurate and more adaptable control is a link or feedback from the output to the input of the system . In order to obtain more accurate bontrol, the controlled signal c(t) must be fed back and compared with the reference input , and an actuating signal proportional to the difference of the output and the input must be sent through the system to correct the error. A system with one or more feedback pat(s like that just described is called a closed-loop system. human being are probably the most complex and sophisticated feedback control system in existence. A humanbeing may be considered to be a control system with many inputs and outputs, capable of carrying out highly complex operations.To illustrate the human being as a feedback control system , let us consider that the objective is to reach for an object on aperform the task. The eyes serve as a sensing device which feeds back continuously the position of the hand . The distance between the hand and the object is the error , which is eventually brought to zero as the hand reacher the object. This is a typical example of closed-loop control. However , if one is told to reach for the object and then is blindolded, one can only reach toward the object by estimating its exact position. It isAs anther illustrative example of a closed-loop control system, shows the block diagram of the rudder control system ofThe basic alements and the bloca diagram of a closed-loop control system are shown in fig. In general , the configuration of a feedback control system may not be constrained to that of fig & . In complex systems there may be multitude of feedback loops and element blocks.数控在先进制造技术领域最根本的观念之一是数控(NC)。

X62W铣床数控化改造外文文献翻译、中英文翻译、外文翻译

X62W铣床数控化改造外文文献翻译、中英文翻译、外文翻译

X62W CNC milling machine transformation1 general CNC transformation of the need for analysisOur about 3200000 existing machine tools, the machine tool technol ogy status of ageing is serious, according to statistics, about 30% of the total country equipment in more than 16 years, of which nearly 30% of age more than 26 years, all these show the present our country did no t go mainly rely on progress of science and technology of machine tools to transform track. In addition, with the development of science and tec hnology, production is dependent on the degree of equipment increases i ncreasingly, the crop of the enterprise, quality, efficiency, cost, safety an d environmental protection and labor emotions get equipment restrict, rea lize the modernization of enterprise oneself be imperative. But according to the data, our metal cutting machine tool production only accounted for similar equipment to have an amount 1 / 28, such as the annual produ ction of all the machines used to replace the old machine tool needs 28 years so, our country is solved at present equipment technical progress is the main way of machine tools.2 domestic and foreign research present situationIn today's world, industrial developed country to machine tool industr y height seriously, competing for the development of mechanical and ele ctrical integration, high precision, high efficiency, high automation and ad vanced machine tool, in order to accelerate the industrial and economic development. For a long time, Europe and the United States, Asia in the international market are in fierce competition, has formed an invisible fr ont, especially with microelectronics, computer technology, numerical cont rol machine tools in the nineteen eighties later accelerated development, put forward more requirements of all users, had become the four big int ernational machine tool exhibition to display machine tool manufacturers advanced technology, for the user, enlarge the market focus. The more f amous control system : Japan FANUC series, Mitsubishi series, OKUNIA series, SODICK series, series of Hitachi, Germany SIEMENS series, DE CKEL series, Heidenhain series, HELLER series, the United States ALLE N-BRADLEY ( AB ) series, CINCINNANTI series, Num series, FIDIA seri es of France, Italy, Spain, Switzerland FAGOR series, AG series of dom estic series.In the United States, Japan and Germany and other developed coun tries, they will machine transformation as a new economic growth sector, the business scene, is in the golden age. As the machine tool and the continuous advancement of technology, machine tools transformation is a "timeless" issue. Transformation of China's machine tool industry, but a lso from the old to the industry into the digital technology-based new industries. In the United States, Japan, Germany, with machine tool of num erical control technical reformation and production line has a broad mark et, has formed a production line of CNC machine tool and the new indu stry. In the United States, reconstruction of machine tool industry called machine regeneration ( Remanufacturing ) industry. Engaged in renewabl e industry's well-known companies: Bertsche engineering company, ayton machine tool company, Devlieg-Bullavd ( PO ) services group, US equi pment company. The United States company has been in China for the company. Rebuilding of machine tool industry in Japan called machine m odified ( Retrofitting ) industry. Engaged in refitting industry well-known c ompanies have: Doomsday engineering group, three post machinery com pany, Chiyoda engineering machine company, Nozaki engineering compa ny, Hamada engineering company, Yamamoto engineering company.Catch up with the pace of computer system structure, accelerate the development of NC system for NC development speed, has become the main trend. The fourth generation computer engineering structure and m icroelectronic technology as the basis, make full use of existing computer hardware, software resources, development of bus type, module type, o pen type, embedded on a flexible NC system, which is suitable for mach ining complex parts, vertical machine tool with CNC system, but also for future automation upgrades the function may be expanded requirements.China 's NC system development has the following 3 features:( 1 ) system of high-grade numerical control technology has been a breakthrough. As of I type numerical control system, with multi axis linka ge function, fast feed speed in 1.67m / s above, have stronger communi cation, management function.( 2) universal CNC system is a mature technology. Beijing Machine Tool Research Institute BS9l system, these systems are generally equipp ed with CRT display, can be configured to DC and AC servo drive, 2 ~ 4 shaft linkage.( 3) the economic type CNC system still has vast market prospect. As a result of this kind of system has the advantages of simple structur e, cheap price, very suitable for small and medium enterprises in China,is still the most widely applied in CNC system. A typical Nanjing gener ous JWK series.Our country is big country of production of machine tools, it is the u se of power. NC machine tool is the key to the development of machine ry industry products, China's CNC machine tool in machine tool products in the proportion of the overall low level of. But our country is a develo ping country, a lot of enterprises financial weakness, not likely to spend a lot of money on a lot of new CNC machine tools, while a large numb er of universal machine tool can not be all eliminated.Therefore, the transformation of general machine tools CNC machine is a effective way to improve the rate of NC machine tools transformati on, less cost, reform targeted, time is short, after the transformation of t he machine tool are able to overcome the original machine faults and pr oblems, high production efficiency.3 basic scheme comparison and selectionNC transformation of the main general plan shall include the followin g contents: the servo drive system, numerical control device selection, el ectrical equipment, mechanical design, CNC hardware system. Show cent to narrate as follows.The 3.1 servo drive systemServo system is a important part of NC machine tool, its performanc e will directly affect the machining accuracy, surface quality and producti on efficiency, it can be divided into 3 kinds, namely, open loop, closed l oop, loop.3.1.1 open loop systemOpen loop system is the most simple servo, stepper motor as the o pen loop system main device, it has the advantages of simple structure ( electrical control and drive circuit is simple ), small volume, light weight, low price, convenient repair and maintenance characteristics3.1.2 closed loop systemClosed loop system, its structure is complex, technical difficulty is gr eat, testing and repair more difficult, cost is high. Closed loop control ca n achieve good accuracy of machine tools, to compensate for mechanica l transmission system in a variety of error, eliminate the gap, interferenc e on the accuracy of processing, generally applied to the high requireme nts of NC equipment.3.1.3 semi closed loop systemSemi closed loop system with closed-loop system similar to, the posi tion detection device is mounted on the execution component, but mount ed on the drive motor end or the end of the drive rod, indirectly measur ed actuator position or displacement. Due to its wide range of speed ( 0.1 - 3OOO R / rain ), strong overload capacity, and the feedback control, the precision can reach 0.01 ~ 0.001nlln, as fast as 0.5 m / s, so its p erformance is far superior to the stepping motor open loop control, and t he feedback link does not include most of mechanical transmission comp onents, simple debugging ratio closed loop, the system stability can be e asily ensured, than the closed loop is easy to realize. Therefore, using a closed-loop system, is more reliable and feasible.3.1.4 AC, DC servo motor comparisonClosed loop, half closed loop system can be AC or DC servo motor, the AC speed regulation gradually expanding the scope of application, s eems to have replaced DC servo trend. But AC servo control of complic ated structure, high technical difficulty, popularity is not wide, and the pri ce is high ( DC servo motor 1.5 ~ 20000 yuan / Taiwan, AC servo mot or is 2 - 30000 ) in addition, compared to the DC servo motor AC serv o motor with large inertia, the small inertia, debugging difficulty big, whe n the sources are more difficult to repair components. DC servo motor p rinciple similar to DC motor, control system technology is more mature, spread wide, its main drawback is the large volume, large weight, but als o with the commutator and brush, increased repair workload.Through the comparison, the success rate, technical difficulty, precisi on and investment and other factors, decided to adopt DC servo loop co ntrol.3.2 numerical control deviceNumerical control device also has a variety of scheme selection. For example, can all of its own design, production; can use SBCs or STD module control; can use readily available numerical control device for a small number of applicable changes or matching. In the factory's practica l application, generally use the following 2 kinds of solution. A kind of cir cumstance is required for the function and requirement of ready-made C NC device can meet, then used mostly to buy ready-made products solu tion, because of own design is not only a waste of time, investment is n ot necessarily can save investment, more often, and quality do not nece ssarily guarantee. Another kind of circumstance is not to buy off-the-shelf products to achieve some special function, then mostly adopt buy price performance ratio as high performance close to the device, and then to supplement or transformation, at least also bought STD template or indu strial control computer, single board computer to make.According to the selected DC servo drive and processing requiremen ts, the numerical control device can realize closed loop ( loop ) of contr ol, provides the analog control signal, receives the half closed loop feed back signal to control; three coordinate axis of motion, wherein at least t o simultaneously control linkage to complete the arc differential complem ent; in the processing of can use different size cutter, CNC device with cutting tool radius and length compensation in NC machining, so accordi ng to the contour programming and can adapt to the size of tool change, in order to meet the needs of future development and clear structure, d ecided to adopt the STD template, modular design.3.3 other electrical devicesIn numerical control transformation, also needs to be combined with the numerical control device and servo drive configuration characterized by other electrical parts, including the strong and weak electrical signal c onversion, transmission or processing necessary. The input / lucky bird o ut interface to consider whether isolation, shielding requirements; in additi on, but also configure the needed power, all kinds of protection circuit, a uxiliary circuit detecting display.3.4 mechanical partsIn the equipment of numerical control transformation, although is the core part of CNC, involve more is microelectronics and electrical, but n ot of all. If you ignore the mechanical aspects according to the character istics of CNC machine tools for the corresponding necessary changes, or in the transformation of the design and manufacture of endless and rea sonable, the results will give numerical control transformation brings beat all difficulties, and may even lead to failure because of mechanical prob lems.3.5 CNC numerical control systemThe CNC system is composed of CPU memory template; servo mot or interface circuit board; the keyboard, display interface circuit board an d a switch quantity input, output interface circuit board. Each template m ain function is as follows.3.5.1CPU memory boardThe board carried out various data operations, timer in the interventi on, timing execution system program, coordination, management of vario us parts of the circuit to work.In addition, also has a power down protection, power on reset and generates a pulse signal and other functions. At the same time, board m emory, for storing system software, computing the results of staging and storage parts processing program. Plate communicationInterface for the boards and peripherals to provide a convenient com munication.3.5.2 servo motor interface circuit boardThe plate is connected to the servo motor and the CPU bridge. CP U issued a servo motor control instruction code, through the template D / A conversion, operational amplifier after being sent to the motor drive s ource, thus realizing the electrical automatic control. At the same time th e motor running state, through the detecting device of the pulse, in the plate after processing, in the form of code into CPU, CPU adjust motor control instruction, thereby forming displacement closed loop system. If th e pulse signal by F / V conversion, can get the speed control unit feedb ack voltage, which constitute a closed loop system.X62W铣床数控化改造1.普通机床数控化改造的必要性分析我国现有机床320多万台,这些机床技术状况老化严重,据统计,全国30%左右设备在16年以上,其中近30%的役龄超过了26年,这些都说明目前我国还没有走上主要依靠科技进步对机床进行改造的轨道。

数控机床改造英文原文及翻译

数控机床改造英文原文及翻译

The Numerical Control Lathe TransformsFirst, numerical control system development summary brief history and tendencyIn 1946 the first electronic accounting machine was born in the world, this indicated the humanity created has been possible to strengthen and partially to replace the mental labor the tool. It with the humanity these which in the agriculture, the industry society created only is strengthens the physical labor the tool to compare, got up the quantitive leap, entered the information society for the humanity to lay the foundation.After 6 years, in 1952, computer technology applied to the engine bed , the first numerical control engine bed were born in US. From this time on, the traditional engine bed has had the archery target change. Since nearly half century, the numerical control system has experienced two stages and six generation of development.1.1 Numerical control (NC) stage (1952 ~ 1970)The early computer operating speed is low, was not big to then science computation and the data processing influence, but could not adapt the engine bed real-time control request. The people can not but use numeral logic circuit "to build" to become an engine bed special purpose computer to take the numerical control system, is called the hardware connection numerical control (HARD-WIRED NC), Jian Chengwei numerical control (NC). Along with the primary device development, this stage has had been through repeatedly three generations, namely 1952 first generation of -- electron tube; 1959 second generation of -- transistor; 1965 third generation -- small scale integration electric circuit.1.2 Computer numerical control (CNC) stage (in 1970 ~ present)In 1970, the general minicomputer already appeared and the mass production. Thereupon transplants it takes the numerical control system the core part, from this time on entered the computer numerical control (CNC) the stage ("which should have computer in front of the general" two characters to abbreviate). In 1971, American INTEL Corporation in the world first time the computer two most cores part -- logicunits and the controller, used the large scale integrated circuit technology integration on together the chip, called it the microprocessor (MICROPROCESSOR), also might be called the central processing element (to be called CPU).The microprocessor is applied to 1974 in the numerical control system. This is because minicomputer function too strong, controlled an engine bed ability to have wealthily (therefore once uses in controlling the multi- Taiwan engine bed at that time, called it group control), was inferior to used the microprocessor economy to be reasonable. Moreover then small machine reliability was not ideal. The early microprocessor speed and the function although insufficiently are also high, but may solve through the multi-processor structure. Because the microprocessor is the general-purpose calculator core part, therefore still was called the computer numerical control.In 1990, PC machine (personal computer, domestic custom had called microcomputer) the performance has developed to the very high stage, may satisfiedly take the numerical control system core part the request. The numerical control system henceforth entered based on the PC stage.In brief, the computer numerical control stage has also experienced three generations. Namely 1970 fourth generation of -- minicomputer; 1974 five dynasties --microprocessor and 1990 sixth generation -- (overseas was called PC-BASED) based on PC.Also must point out, although overseas already renamed as the computer numerical control (namely CNC).Also must point out, although overseas already renamed as the computer numerical control (namely CNC), but our country still the custom called the numerical control (NC). Therefore we daily say "numerical control", the materially already was refers to "computer numerical control".1.3 The numerical control future will develop tendency1.3.1 open style continues to, to develop based on the PC sixth generation of directionThe software and hardware resources has which based on PC are rich and so on the characteristic, the more numerical controls serial production factory can step ontothis path. Uses PC machine to take at least its front end machine, processes the man-machine contact surface, the programming, the associationQuestion and so on net correspondence, undertakes the numerical control duty by the original system. PC machine has the friendly man-machine contact surface, will popularize to all numerical controls system. The long-distance communication, the long-distance diagnosis and the service will be more common.1.3.2 approaches and the high accuracy developmentThis is adapts the engine bed to be high speed and the high accuracy direction need to develop.1.3.3 develops to the intellectualized directionAlong with the artificial intelligence in the computer domain unceasing seepage and the development, the numerical control system intellectualized degree unceasingly will enhance.(1) applies the adaptive control technologyThe numerical control system can examine in the process some important information, and the automatic control system related parameter, achieves the improvement system running status the goal.(2) introduces the expert system instruction processingThe skilled worker and expert's experience, the processing general rule and the special rule store in the system, take the craft parameter database as the strut, the establishment has the artificial intelligence the expert system.(3) introduces the breakdown to diagnose the expert system(4) intellectualized numeral servo driveMay through the automatic diagnosis load, but the automatic control parameter, causes the actuation system to obtain the best movement.Second, engine bed numerical control transformation necessity2.1 Microscopic looks at the transformation the necessityFrom on microscopic looked below that, the numerical control engine bed has the prominent superiority compared to the traditional engine bed, moreover thesesuperiority come from the computer might which the numerical control system contains.2.1.1 may process the traditional engine bed cannot process the curve, the curved surface and so on the complex components.Because the computer has the excellent operation ability, may the instant accurately calculate each coordinate axis instant to be supposed the movement physiological load of exercise, therefore may turn round the synthesis complex curve or the curved surface.2.1.2 may realize the processing automation, moreover is the flexible automation, thus the efficiency may enhance 3 ~ 7 times compared to the traditional engine bed.Because the computer has the memory and the memory property, may the procedure which inputs remember and save, then the order which stipulated according to the procedure automatic carries out, thus realization automation. The numerical control engine bed so long as replaces a procedure, may realize another work piece processing automation, thus causes the single unit and the small batch of production can automate, therefore is called has realized "flexible automation".2.1.3 processings components precision high, size dispersion degree small, makes the assembly to be easy, no longer needs "to make repairs".2.1.4 may realize the multi- working procedures centralism, reduces the components in engine bed between frequent transporting.2.1.5 has auto-alarm, the automatic monitoring, automatic compensation and so on the many kinds of autonomy function, thus may realize long time nobody to safeguard the processing.2.1.6 advantage which derives by above five.For example: Reduced worker's labor intensity, saved the labor force (a person to be possible to safeguard the multi- Taiwan engine bed), reduced the work clothes, reduced the new product trial manufacturing cycle and the production cycle, might to the market demand make rapid reaction and so on.Above these superiority are the predecessor cannot imagine, is an extremely significant breakthrough. In addition, the engine bed numerical control carries outFMC (flexible manufacture unit), FMS (flexible manufacture system) as well as CIMS (computer integration manufacture system) and so on the enterprise becoming an information based society transformation foundation. The numerical control technology already became the manufacturing industry automation the core technology and the foundation technology.2.2 Great watches the transformation the necessityFrom on macroscopic looked that, the industry developed country armed forces, the airplane weapon industry, in the end of the 70's, at the beginning of the 80's started the large-scale application numerical control engine bed. Its essence is, uses the information technology to the traditional industry (including the armed forces, airplane weapon industry) carries on the technological transformations. Except that uses outside the numerical control engine bed, FMC, FMS in the manufacture process, but also includes in the product development carries out CAD, CAE, CAM, the hypothesized manufacture as well as carries out MIS in the production management (management information system), CIMS and so on. Because uses the information technology to the country foreign troops, the airplane weapon industry carries on the thorough transformation (to call it becoming an information based society), finally causes them the product in the international military goods and in the goods for civilian use market the competitive power greatly is the enhancement. But we in the information technology transformation tradition industry aspect compared to the developed country to fall behind approximately for 20 years. Like in our country engine bed capacity, numerical control engine bed proportion (numerical control rate) to 1995 only then 1.9%, but Japan has reached 20.8% in 1994, therefore every year has the massive mechanical and electrical products import. This also on from on macroscopic explained the engine bed numerical control transformation necessity. Thord, the numerical control transformation content and superiorly lacks3.1 Transformation industry startingIn US, Japan and Germany and so on the developed country, their engine bedtransforms took the new economical growth profession, thrives abundantly, is occupying the golden age. As a result of the engine bed as well as the technical unceasing progress, the engine bed transformation is "the eternal" topic. Our country's engine bed transformation industry, also enters from the old profession to by the numerical control technology primarily new profession. In US, Japan, Germany, have the broad market with the numerical control technological transformations engine bed and the production line, has formed the engine bed and the production line numerical control transformation new profession. In US, the engine bed transformation industry is called the engine bed regeneration (Remanufacturing) industry. Is engaged in the regeneration industry famous company to include: The Bertsche engineering firm, the ayton engine bed company, Devlieg-Bullavd (are valuable) serves the group, the US equipment company and so on. The American valuable company has set up the company in China. In Japan, the engine bed transformation industry is called the engine bed to reequip (Retrofitting) industry. Is engaged in the reequipment industry famous company to include: Big indentation project group, hillock three mechanical companies, thousand substitute fields labor machine company, wild engineering firm, shore field engineering firm, mountain this engineering firm and so on.3.2 Numerical control transformation contentThe engine bed and the production line numerical control transformation main content has following several points:First is extensively recovers the function, to the engine bed, the production line has the breakdown partially to carry on the diagnosis and the restoration;Second is NC, the addend reveals the installment on the ordinary engine bed, or adds the numerical control system, transforms the NC engine bed, the CNC engine bed;Third is renovates, for increases the precision, the efficiency and the automaticity, to the machinery, the electricity partially carries on renovates, reassembles the processing to the machine part, extensively recovers the precision; Does not satisfy the production request to it the CNC system to carry on the renewal by newest CNC;Fourth is the technology renews or the technical innovation, for enhances theperformance or the scale, or in order to use the new craft, the new technology, carries on the big scale in the original foundation the technology to renew or the technical innovation, the great scope raises the level and the scale renewal transformation. The new electrical system transforms after, how carries on the debugging as well as the determination reasonable approval standard, also is the technology preparatory work important link. The debugging work involves the machinery, the hydraulic pressure, the electricity, the control, and so on, therefore must carry on by the project person in charge, other personnel coordinate. The debugging step may conform to simplicity to numerous, from infancy to maturity, carries on from outside to in, after also may the partial overall situation, after first the subsystem the3.3 The numerical control transformation superiorly lacks3.3.1 reduced investment costs, the date of delivery are shortWith purchases the new engine bed to compare, may save 60% ~ 80% expense generally, the transformation expense is low. Large-scale, the special engine bed especially is specially obvious. The common large-scale engine bed transforms, only spends the new engine bed purchase expense 1/3, the date of delivery is short. But some peculiar circumstances, like the high speed main axle, the tray automatic switching unit manufacture and the installment too requires a lot of work, costs a great deal of money, often transforms the cost to enhance 2 ~ 3 times, with purchases the new engine bed to compare, only can economical invest about 50%.3.3.2 machine capability stable are reliable, the structure is limitedUses foundation and so on lathe bed, column all is heavy but the firm casting component, but is not that kind of welding component, after the transformation engine bed performance high, the quality is good, may take the new equipment continues to use many years. But receives the original mechanism the limit, not suitably makes the unprecedented transformation.3.3.3 familiar understood the equipment, is advantageous for the operation serviceWhen purchases the new equipment, did not understand whether the new equipment can satisfy its processing request. The transformation then otherwise, may precisely calculate the engine bed the processing ability; Moreover, because manyyears use, the operator already understood to the engine bed characteristic, uses and services the aspect to train the time in the operation short, effective is quick. The transformation engine bed as soon as installs, may realize the capacity load revolution.3.3.4 may fully use the existing conditionMay fully use the existing ground, does not need to like buys when the new equipment such to have reto construct the ground.3.3.5 may use the newest control technologyenhances the production equipment the automated level and the efficiency, improves the equipment quality and the scale, alters to the old engine bed now the horizontal engine bed.Fourth, numerical control system choiceWhen the numerical control system mainly has three kind of types, the transformation, should act according to the special details to carry on the choice.4.1 Step-by-steps the open system which the electrical machinery drivesThis system servo drive mainly is step-by-steps the electrical machinery, the power step-by-steps the electrical machinery, the battery solution pulse motor and so on. Entering sends out which by the numerical control system for instruction pulse, after the actuation electric circuit control and the power enlargement, causes to step-by-step the electrical machinery rotation, through gear vice- and ball bearing guide screw vice- actuation executive component. So long as the control command pulse quantity, the frequency as well as the circular telegram order, then may control the executive component movement the displacement quantity, the speed and the heading. This kind of system does not need the physical location and the velocity feedback which obtains to the input end, therefore called it the open system, this system displacement precision mainly decided in step-by-steps the electrical machinery angular displacement precision, transmission part and so on gear guide screw pitches the precision, therefore the system displacement precision is low.This system structure simple, debugging service convenient, work reliable, cost low,is easy to reequip successfully.4.2 The asynchronous motor or the direct current machine drive, diffraction grating survey feedback closed loop numerical control systemThis system and the open system difference is: Physical location feedback signal which by position detector set and so on the diffraction grating, induction synchromesh obtains, carries on the comparison as necessary with the given value, two interpolations enlargements and the transformation, the actuation implementing agency, by the speed which assigns turns towards the elimination deviation the direction movement, until assigns the position and the feedback physical location interpolation is equal to the zero. The closed loop enters for the system Enters for the system complex in the structure compared to the split-ring, the cost is also high, requests strictly to the environment room temperature. The design and the debugging is all more difficult than the open system. But may obtain compared to the split-ring enters for a system higher precision, quicker speed, actuation power bigger characteristic target. May act according to the product specification, decided whether uses this kind of system.4.3 The direct current servo electrical machinery drives, encoder feedback semi-closure link numerical control systemHalf closed-loop system examination part installs in among passes in the moving parts, indirectly surveys the executive component the position. It only can compensate a system ring circuit interior part of part the error, therefore, its precision compared to closed-loop system precision low, but its structure and the debugging all compares the closed-loop system to be simple. In makes the angular displacement examination part and the speed examination part and the servo electrical machinery time a whole then does not need to consider the position detector set installs the question.The current production numerical control system company factory quite are many, overseas famous company like German SIEMENS Corporation, Japanese FANUC Corporation; Native corporation like China Mount Everest Corporation, Beijing astronautics engine bed numerical control system group company, Central China numerical control company and Shenyang upscale numerical control countryengineering research center.When choice numerical control system mainly is each kind of precision which the engine bed must achieve after the numerical control transformation, actuates the electrical machinery the power and user's request.Fifth, in the numerical control transformation the main mechanical part reequips the discussionA new numerical control engine bed, must achieve in the design that, Has the high static dynamic rigidity; Movement vice- between friction coefficient small, the transmission is ceaseless; The power is big; Is advantageous for the operation and the service. When engine bed numerical control transformation should meet the above requirements as far as possible. Cannot think the numerical control installment and the ordinary engine bed connects in has met the numerical control engine bed requirements together, but also should carry on the corresponding transformation to the major component to enable it to achieve the certain design request, can obtain the anticipated transformation goal.5.1 Skids guide railSaid to the numerical control lathe that, the guide rail besides should have the conventional lathe guidance precision and the technology capability, but also must have good bears the friction, the attrition characteristic, and the reduction but sends the dead area because of the friction drag. At the same time must have the enough rigidity, by reduces the guide rail to distort to processes the precision the influence, must have the reasonable guide rail protection and the lubrication.5.2 GearThe common engine bed gear mainly concentrates in the headstock and the gear box. In order to guarantee the transmission precision, on the numerical control engine bed uses the gear precision class is all higher than the ordinary engine bed. Must be able to achieve the ceaseless transmission in the structure, thus transforms time, the engine bed main gear must satisfy the numerical control engine bed the request, by guarantees the engine bed processing precision.5.3 Skids the guide screw and the ball bearing guide screwThe guide screw transmission relates directly to the transmission chain precision. The guide screw selects mainly is decided requests and drives the torque request in the job precision. Is not used by job precision request Gao Shike skids the guide screw, but should inspect the original guide screw attrition situation, like the pitch error and the pitch accumulative error as well as matches the nut gap. The ordinary circumstances skid the guide screw to be supposed not to be lower than 6 levels, the nut gap oversized then replaces the nut. Uses skids the guide screw relative ball bearing guide screw price to be low, but satisfies the precision high components processing with difficulty.The ball bearing guide screw rubs loses slightly, the efficiency is high, its transmission efficiency may above 90%; Precision high, the life is long; When start moment of force and movement the moment of force approaches, may reduce the electrical machinery to start the moment of force. Therefore may satisfiedly compare the high accuracy components processing request.5.4 Safe protectionThe effect must take the security as a premise. Transforms in the engine bed must take the corresponding measure according to the actual situation, cuts noticeable. The ball bearing guide screw vice- is the precision part, when the work must take strict precautions against the dust is specially the scrap and the hard sand grains enters the roller conveyer. On longitudinal guide screw also coca overall sheet iron safety mask. The big carriage with skids two end surfaces which the guide rail contacts to have to seal, prevented absolutely the flinty granulated foreign matter enters the sliding surface damage guide rail.Sixth, After the engine bed electrical system transformation, to operates, the programmers inevitably brings the new request. Therefore ahead of time carries on new system knowledge training to the operator and the programmers to be extremely important, after otherwise will affect the transformation the engine bed rapid investment production. The training content should include the new operation kneading board disposition, the function, the instruction meaning generally; Newsystem functional scope, application method and with old system difference; Maintenance maintenance request; Programming standard and automated programming and so on. The key point is makes, gets a good grasp of the operating manual and the programming instruction booklet.The numerical control transforms se Transforms the scope according to each equipment differently, must beforehand design the connection partial transformations, if transforms completely, should design the electro-mechanical transformation connection, the operation kneading board control and the disposition, the interconnection partial contacts, the parameter measuring point, services the position and so on, the request operates and services conveniently, reasonable, the line moves towards, center the small junction smoothly few, the strong and the weak electrical noise is smallest, has the suitable allowance and so on. Partial transformation, but also needs to consider the new old system the performance match, the voltage polarity and the size transformation, install the position, the digital-analog conversion and so on, when the necessity must manufacture the transformation connection voluntarily. Sixth, veral examples6.1 Transforms the X53 milling machine with SIEMENS 810MIn 1998, the company invested 200,000 Yuan, with German Simens the 810M numerical control system, the 611A exchange servo drive system sds was the X53 milling machine carries on X, Y, the Z three axle numerical control transformation to a company's model; Retained the original main axle system and the cooling system; The transformation three axle has used the roller lead screw and the gear drive organization on the machinery. The entire transformation work including the machine design, the electrical design, the PLC procedure establishment and the debugging, the engine bed overhaul, finally is the entire machine installment and the debugging. After the milling machine transforms, processing effective stroke X/Y/The Z axis respectively is 88.0/270/28 billion mm; Maximum speed X/Y/The Z axis respectively is 5000/1500/800 mm/Min; Manual speed X/Y/The Z axis respectively is 3000/1000/500 mm/Min; The engine bed processing precision achieves ±0.001mm.The engine bed three coordinates linkage may complete each kind of complex curve or the curved surface processing.6.2 Transforms the C6140 lathe with GSK980T and the exchange servo drive system sdsIn 2000, with Guangzhou numerical control plant production GSK980T numerical control system, the DA98 exchange servo unit and 4 locations automatic tool rests to an electrical machinery branch factory C6140 lathe X, the Z two axes carries on the numerical control transformation; Retained the original main axle system and the cooling system; The transformation two axes have used the roller lead screw and with the ambulacrum transmission system on the machinery. Entire transformation work including machine design, electrical design, engine bed overhaul and entire machine installment and debugging. After the lathe transforms, processing effective stroke X/The Z axis respectively is 3.90/73 million mm; Maximum speed X/The Z axis respectively is 120.0/3 million mm/Min; The manual speed is 400mm/Min; Manual is fast is X/The Z axis respectively is 120.0/3 million mm/Min; The engine bed smallest migration unit is 0.001mm.6.3 Transforms the X53 milling machine with SIEMENS 802SIn 2000, the company invests 120,000 Yuan, with German Simens the 802S numerical control system, step-by-steps the actuation system is the X53 milling machine carries on X, Y, the Z three axle numerical control transformation to company's another model; Retained the original main axle system and the cooling system; The transformation three axle has used the roller lead screw and the gear drive organization on the machinery. The entire transformation work including the machine design, the electrical design, the engine bed overhaul, finally is the entire machine installment and the debugging. After the milling machine transforms, processing effective stroke X/Y/The Z axis respectively is 63.0/240/28 billion mm; Maximum speed X/Y/The Z axis respectively is 3000/1000/600 mm/Min; Manual enters for speed X/Y/The Z axis respectively is 200.0/800/5 billion mm/Min; The smallest motion unit is 0.001mm.。

数控技术外文文献翻译

数控技术外文文献翻译

数控技术外文文献翻译(含:英文原文及中文译文)英文原文The development trend of numerical control technology AbstractThe current trends in the development of numerical control technology and equipment in the world and the status quo of the development and industrialization of CNC equipment technology in China are briefly introduced. On this basis, we discuss the development of CNC technology and equipment in China under the new environment of China's accession to the WTO and further opening to the outside world. The importance of improving the level of China's manufacturing informatization and international competitiveness, and put forward some views on the development of China's CNC technology and equipment from both strategic and strategic aspects.The technological level and degree of modernization of the equipment industry determine the level of the entire national economy and the degree of modernization. Numerical control technology and equipment are the development of emerging high-tech industries and cutting-edge industries (such as information technology and its industries, biotechnology and its industries, aviation, aerospace, etc.) (Defense Industry Industry) enabling technology and basic equipment. Marx oncesaid that “the difference between various economic times is no t what is produced but how it is produced and what labor data it is used to produce”. Manufacturing technology and equipment are the most basic production materials for human production activities, and numerical control technology is the core technology of today's advanced manufacturing technologies and equipment. In the manufacturing industry of the world today, CNC technology is widely used to improve manufacturing capabilities and levels, and to improve the adaptability and competitiveness of dynamic markets. In addition, various industrialized countries in the world have also listed numerical control technology and numerical control equipment as strategic materials of the country. They not only take significant measures to develop their own numerical control technologies and their industries, but also have the key technology and equipment of “high-precision” numerical control. Our country adopts a policy of blockade and restriction. In short, the vigorous development of advanced manufacturing technologies centered on numerical control technology has become an important way for all developed countries in the world to accelerate economic development and improve their overall national strength and national status.Numerical control technology is a technology that uses digital information to control mechanical movement and work process. Numerical control equipment is a mechatronic product formed by thepenetration of new technologies represented by numerical control technology into traditional manufacturing industries and emerging manufacturing industries, namely, so-called digital equipment. Its technical scope covers many fields: (1) machinery manufacturing technology; (2) information processing, processing, and transmission technology; (3) automatic control technology; (4) servo drive technology;(5) sensor technology; (6) software Technology and so on. Keywords: CNC technology, machinery manufacturing, information processing, sensors1 Development Trends of Numerical Control TechnologyThe application of numerical control technology has not only brought about revolutionary changes in the traditional manufacturing industry, but also made manufacturing a symbol of industrialization. With the continuous development of numerical control technology and the expansion of application fields, he has made important contributions to the national economy and people's livelihood (IT, automotive The development of light industry, light industry, medical care, etc. is playing an increasingly important role, because the digitalization of the equipment required by these industries is a major trend of modern development. From the current trend of numerical control technology and its equipment development in the world, its main research hotspots are the following aspects [1~4].1.1 New trends in high-speed, high-precision processing technology and equipmentEfficiency and quality are the mainstays of advanced manufacturing technology. High-speed, high-precision machining technology can greatly improve efficiency, improve product quality and grade, shorten production cycle and increase market competitiveness. To this end, the Japanese Advanced Technology Research Institute will list it as one of the five major modern manufacturing technologies. The International Association of Production Engineers (CIRP) has identified it as one of the central research directions for the 21st century.In the passenger car industry, the production cycle of 300,000 vehicles per year is 40 seconds per vehicle, and multi-species processing is one of the key issues that must be addressed for car equipment. In the aviation and aerospace industries, the parts processed by them are mostly thin-walled. With thin ribs, the rigidity is poor, and the material is aluminum or aluminum alloy. These ribs and walls can be processed only when the high cutting speed and cutting force are small. Recently, the method of “hollowing out” large-size aluminum alloy billets has been used to manufacture large parts such as wings and fuselage to replace multiple parts and assembled by numerous rivets, screws, and other coupling methods to obtain strength, stiffness, and reliability of components. improve. All of these require high-speed, high-precision andhigh-flexibility for processing equipment.From the standpoint of EMO2001, the feed rate of high-speed machining centers can reach 80m/min, or even higher, and the airspeed can reach around 100m/min. At present, many automobile plants in the world, including China's Shanghai General Motors Corporation, have adopted a part of the production line consisting of a high-speed machining center to replace the combined machine tools. The HyperMach machine tool feed rate of CINCINNATI, USA is up to 60m/min, the speed is 100m/min, the acceleration is 2g, and the spindle speed has reached 60,000r/min. It takes only 30 minutes to machine a thin-walled aircraft part, and the same part takes 3h for general high-speed milling and 8h for normal milling; the spindle speed and acceleration of the twin-spindle lathe of DMG, Germany, reach 12*!000r/mm respectively. And 1g.In terms of machining accuracy, in the past 10 years, the machining accuracy of ordinary CNC machine tools has increased from 10μm to 5μm, precision machining centers have increased from 3~5μm to 1~1.5μm, and ultra-precision machining precision has begun to enter the nanometer level. (0.01μm).In terms of reliability, the MTBF value of foreign numerical control devices has reached more than 6000 hours, and the MTBF value of the servo system has reached more than 30,000 hours, showing very highreliability.In order to achieve high-speed, high-precision machining, the supporting functional components such as electric spindles and linear motors have been rapidly developed and the application fields have been further expanded.1.2 Rapid development of 5-axis simultaneous machining and compound machiningThe use of 5-axis simultaneous machining of 3D surface parts allows cutting with the best geometry of the tool, resulting in not only a high degree of finish, but also a significant increase in efficiency. It is generally considered that the efficiency of a 5-axis machine tool can be equal to 2 3-axis linkage machines. Especially when using ultra-hard material milling tools such as cubic boron nitride for high-speed milling of hardened steel parts, 5-axis simultaneous machining can be compared with 3-axis linkage. Processing to play a higher efficiency. In the past, due to the complexity of the 5-axis linkage CNC system and the host machine structure, the price was several times higher than that of the 3-axis linkage CNC machine tool, and the programming technology was more difficult, which restricted the development of 5-axis linkage machine tools.At present, due to the emergence of electric spindles, the structure of the composite spindle head that realizes 5-axis simultaneous machining isgreatly simplified, its manufacturing difficulty and cost are greatly reduced, and the price gap of the numerical control system is reduced. As a result, the development of composite spindle head type 5-axis linkage machine tools and compound machine tools (including 5-sided machine tools) has been promoted.At the EMO2001 exhibition, the new 5-axis machine tool of Nippon Machine Tool Co., Ltd. adopts a compound spindle head, which can realize the processing of four vertical planes and processing at any angle, so that 5-sided machining and 5-axis machining can be realized on the same machine tool. It can realize the processing of inclined surface and inverted cone. Germany DMG company exhibited DMUV oution series machining center, which can be processed in five-face machining and five-axis linkage in a single clamping. It can be directly or indirectly controlled by CNC system control or CAD/CAM.1.3 Intelligentization, openness, and networking have become major trends in the development of modern digital control systemsThe 21st century CNC equipment will be a certain intelligent system. The intelligent content is included in all aspects of the CNC system: in order to pursue the processing efficiency and processing quality in the intelligent, such as the process of adaptive control, process parameters automatically Generated; To improve the driving performance and the use of convenient connection intelligent, such as feed-forward control,adaptive calculation of motor parameters, automatic identification load automatic selection model, self-tuning, etc.; simplify the programming, simplify the operation of intelligent, such as smart The automatic programming, intelligent man-machine interface, etc.; as well as the contents of intelligent diagnosis, intelligent monitoring, convenient system diagnosis and maintenance.In order to solve the problems of traditional CNC system closure and industrial application of CNC application software. At present, many countries have conducted research on open numerical control systems such as NGC of the United States, OSACA of the European Community, OSEC of Japan, and ONC of China. The openness of numerical control systems has become the future of CNC systems. The so-called open CNC system is the development of CNC system can be in a unified operating platform, for machine tool manufacturers and end users, by changing, adding or cutting structure objects (CNC function), to form a series, and can be convenient to the user's special The application and technology are integrated into the control system to quickly realize open numerical control systems of different varieties and different grades to form brand-name products with distinctive personality. At present, the architecture specification, communication specification, configuration specification, operation platform, numerical control system function library and numerical control system function software development toolof open CNC system are the core of current research.Networked CNC equipment is a new bright spot in the international well-known machine tool exposition in the past two years. The networking of CNC equipment will greatly satisfy the requirements of information integration for production lines, manufacturing systems, and manufacturing companies. It is also the basic unit for realizing new manufacturing models such as agile manufacturing, virtual enterprise, and global manufacturing. Some famous domestic and foreign CNC machine tools and numerical control system manufacturing companies have introduced relevant new concepts and prototypes in the past two years. For example, at the EMO 2001 exhibition, the “Cyber Production Center” exhibited by Japan's Mazak company Mazak Production Control Center (CPC); Okuma Machine Too l Company, Japan exhibited “ITplaza” (Information Technology Plaza, IT Plaza); Open Manufacturing Environment (Open Manufacturing Environment, OME), exhibited by Siemens, Germany Etc., reflecting the trend of the development of CNC machine tools to the direction of the network.1.4 Emphasizing the Establishment of New Technology Standards and Specifications1.4.1 About Design and Development of CNC SystemsAs mentioned above, the open CNC system has better versatility, flexibility, adaptability, and expandability. The United States, theEuropean Community, and Japan have implemented strategic development plans one after another, and have conducted the open architecture system specification (OMAC). , OSACA, OSEC) research and development, the world's three largest economies in the short term carried out almost the same set of scientific plans and norms, indicating that the arrival of a new revolution in digital technology. In 2000, China began to conduct research and development of the regulatory framework for China's ONC numerical control system.1.4.2 About CNC StandardsCNC standards are a trend in the development of manufacturing informatization. The information exchange in the 50 years since the birth of CNC technology was based on the ISO 6983 standard. That is how the G and M codes describe how to process. The essential feature is the processing-oriented process. Obviously, he has been unable to meet the high speed of modern CNC technology. The need for development. For this purpose, a new CNC system standard ISO14649 (STEP-NC) is being researched and developed internationally. Its purpose is to provide a uniform data model that can describe the entire life cycle of a product without relying on a neutral mechanism of a specific system. , in order to achieve the entire manufacturing process, and even the standardization of product information in various industrial fields. The emergence of STEP-NC may be a revolution in CNC technology. It will have aprofound impact on the development of CNC technology and even the entire manufacturing industry. First, STEP-NC proposes a brand-new manufacturing concept. In the traditional manufacturing concept, NC machining programs are concentrated on a single computer. Under the new standard, NC programs can be distributed on the Internet. This is the direction of open and networked CNC technology. Secondly, STEP-NC CNC system can also greatly reduce the processing drawings (about 75%), processing program preparation time (about 35%) and processing time (about 50%).At present, European and American countries attach great importance to the research of STEP-NC, and Europe has initiated STEP-NC's IMS plan ( Participation in this program comes from 20 CAD/CAM/CAPP/CNC users, vendors and academic institutions in Europe and Japan. STEPTools of the United States is the developer of global manufacturing data exchange software. He has developed a SuperModel for the information exchange of CNC machine tools. Its goal is to describe all machining processes with a unified specification. This new data exchange format has now been validated on prototype prototypes equipped with SIEMENS, FIDIA and European OSACA-NC numerical control systems.2 Basic Estimates of China's CNC Technology and Its Industrial DevelopmentCNC technology in China started in 1958. The development process in the past 50 years can be roughly divided into three stages: the first stage from 1958 to 1979, which is the closed development stage. At this stage, the development of numerical control technology is relatively slow due to the limitations of foreign technology and China's basic conditions. The second stage is the introduction of technology during the “sixth and fifth” periods of the country, the “seventh five-year plan” period, and the “eighth five-year plan period,”and it will be digested and absorbed to initially establish the stage of the national production system. At this stage, due to the reform and opening up and the country’s attention, as well as the improvement of the research and development environment an d the international environment, China’s CNC technology has made great progress in research, development, and localization of products. The third stage is the implementation of industrialization research in the later period of the "Eighth Five-Year Plan" and the "Ninth Five-Year Plan" period of the country, entering the stage of market competition. At this stage, the industrialization of domestically-manufactured CNC equipment has achieved its essenceSexual progress. At the end of the “Ninth Five-Year Plan” period, the domestic market share of domestic CNC machine tools reached 50%, and the number of domestically-manufactured numerical control systems (pervasive models) also reached 10%.Looking at the development process of CNC technology in China in the past 50 years, especially after four five-year plans, the overall results are as follows:a. It lays the foundation for the development of CNC technology and basically masters modern CNC technology. China has now basically mastered the basic technologies from numerical control systems, servo drives, numerical control mainframes, special planes and their accessories. Most of these technologies already have the basis for commercial development. Some technologies have been commercialized and industrialized.b. Initially formed a CNC industrial base. Based on the research results and the commercialization of some technologies, we have established numerical control system production plants such as Huazhong Numerical Control and Aerospace Numerical Control which have mass production capabilities. Lanzhou Electric Machinery Factory, Huazhong Numerical Control and a number of servo systems and servo motor manufacturers, as well as a number of CNC machine manufacturers such as Beijing No. 1 Machine Tool Plant and Jinan No. 1 Machine Tool Plant. These production plants have basically formed China's CNC industrial base.c. Established a basic team of CNC research, development and management talents.Although significant progress has been made in the research, development, and industrialization of numerical control technology, we must also soberly realize that the research and development of high-end numerical control technologies in China, especially the status quo of the technological level of industrialization and the actual needs of China There is a big gap. Although our country's development speed is very fast in the vertical direction, the horizontal ratio (compared with foreign countries) not only has a gap in the level of technology, but also has a gap in the development speed in certain aspects, that is, the gap in the technological level of some highly sophisticated numerical control equipment has expanded. From the international point of view, the estimated level of China's numerical control technology and industrialization is roughly as follows:a. On the technical level, it will be about 10 to 15 years behind the advanced level in foreign countries, and it will be even bigger in terms of sophisticated technology.b. At the industrialization level, the market share is low, the variety coverage is small, and scale production has not yet been established; the specialized production level of functional components and the complete set capacity are low; the appearance quality is relatively poor; the reliability is not high, and the degree of commercialization is insufficient; The domestic CNC system has not established its own brand effect, andthe user's confidence is insufficient.c. On the ability of sustainable development, the research and development and engineering capabilities of pre-competitive numerical control technology are weak; the application of numerical control technology is not strong; the research and formulation of related standard specifications is lagging behind.The main reasons for analyzing the above gaps are as follows:a. Awareness. Insufficient understanding of the arduous, complex and long-term characteristics of the domestic CNC industry process; Insufficient estimates of market irregularities, foreign blockades, killings, and systems; and insufficient analysis of the application level and capabilities of CNC technology in China.b. Systematic aspects. From the point of view of technology, attention has been paid to the issue of CNC industrialization. It has been a time to consider the issue of CNC industrialization from the perspectives of system and industry chain; there is no complete supporting system of high-quality supporting systems, perfect training, and service networks. .c. Mechanisms. Bad mechanisms have led to brain drain, which in turn has restricted technological and technological route innovations and product innovations, and has constrained the effective implementation of planning. It is often planned to be ideal and difficult to implement.d. Technical aspects. Enterprises have little ability to independentlyinnovate in technology, and the engineering ability of core technologies is not strong. The standard of machine tools is backward, the level is low, and the new standard of CNC system is not enough.3 Strategic Thinking on the Development of CNC Technology and Industrialization in China3.1 Strategic ConsiderationsChina is a manufacturing country, and we must try to accept the transfer of the front-end rather than the back-end in the industrial transfer of the world. That is to master the advanced manufacturing core technologies, otherwise, in the new round of international industrial restructuring, China's manufacturing industry will further “empty core”. At the expense of resources, the environment, and the market, we may obtain only the international "processing centers" and "assembly centers" in the world's new economic structure, rather than the status of manufacturing centers that master core technologies. This will seriously affect our country. The development of modern manufacturing.We should pay attention to numerical control technology and industrial issues from the perspective of national security strategy. First of all, we must look at social security because manufacturing industry is the industry with the largest number of employed people in China. Manufacturing industry development can not only improve the people’s living standards, but also ease the country’s The pressure of employmentguarantees social stability. Secondly, from the perspective of national defense security, Western developed countries classify high-precision numerical control products as national strategic materials and implement embargoes and restrictions on China. The “Toshiba Incident” and the “Cox Report” "This is the best illustration.3.2 Development StrategyFrom the perspective of China’s basic national conditions, taking the country’s strategic needs and the market demand of the national economy as the guide, and aiming at improving the comprehensive competitiveness and industrialization le vel of China’s manufacturing equipment industry, we can use systematic methods to choose to dominate the early 21st century in China. The key technologies for the development and upgrade of the manufacturing equipment industry and supporting technologies and supporting technologies for supporting industrialization development are the contents of research and development and the leap-forward development of the manufacturing equipment industry. Emphasizing the market demand as the orientation, that is, taking CNC terminal products as the mainstay, and driving the CNC industry with complete machines (such as large-scale CNC lathes, milling machines, high-speed, high-precision and high-performance CNC machine tools, typical digital machines, key equipment of key industries, etc.). development of. The focus is on the reliability and production scale of CNC systems andrelated functional components (digital servos and motors, high-speed spindle systems and accessories for new equipment, etc.). Without scale, there will be no high-reliability products; without scale, there will be no cheap and competitive products; of course, CNC equipment without scale in China will be difficult to come to the fore. In the research and development of high-precision equipment, we must emphasize the close integration of production, learning, research, and end-users, and aim at “doing, using, and selling off” as a goal, and implement national research on the will of the country to solve the urgent need of the country. . Before the competition, CNC technology emphasizes innovation, emphasizes research and development of technologies and products with independent intellectual property rights, and lays a foundation for the sustainable development of China's CNC industry, equipment manufacturing industry, and even the entire manufacturing industry.中文译文数控技术的发展趋势摘要本文简要介绍了当今世界数控技术及装备发展的趋势及我国数控装备技术发展和产业化的现状, 在此基础上讨论了在我国加入WTO 和对外开放进一步深化的新环境下, 发展我国数控技术及装备、提高我国制造业信息化水平和国际竞争能力的重要性, 并从战略和策略两个层面提出了发展我国数控技术及装备的几点看法。

分析数控机床改造外文文献翻译、中英文翻译、外文翻译

分析数控机床改造外文文献翻译、中英文翻译、外文翻译

Analysis of transformation of numerical controlmachine toolIn order to survival and development of enterprises, improve the rate of CNC machine tools is necessary. Transformation of the equipment needed for NC machine tools in general, including traditional and recently introduced from abroad, due to a problem can not be put into the machine tool equipment and production lines. First, transform the contents of the NCCNC machine tools and production line transformation of the main contents are: (1) restoration of the original function, machine tools, production lines there is some fault diagnosis and recovery; (2)NC-based, in the general machine tools addend remarkable device or add numerical control system; ( 3) The renovation, to improve accuracy, efficiency and degree of automation, mechanical, electrical parts of the renovation, the mechanical part of there-assembly process, to restore the original precision; can not meet the production requirements of its CNC system be updated with the latest CNC; (4) technology updates or technical innovation, in order to improve performance or grade, or for the use of new technology, new technology, based on the original large-scale technology updates or technical innovation.Second, the development trend of CNC systeml. To open, the sixth generation of PC-based directionThe openness of the PC-based, low-cost, high reliability, rich in natural resources such as hardware and software features, and more CNC system manufacturer will be to go down this path. At least with PC, as its front-end machines, to deal with man-machine interface, programming, networking and communications issues, the original system to take over some tasks PC CNC machines has the friendly interface, will reach all of the CNC system. The remote communication, remote diagnostics and maintenance of applications will be more common.2. To the development of high-speed and high precision.3. To the intelligent direction(1) The application of adaptive control technology. Numerical control system can detect the process of important information and automatically adjust system parameters, improving the system operation status.2) the introduction of expert systems to guide processing. Will be skilled workers and expertise, processing and general laws and special laws into the system to process parameter database support, establish an artificial intelligence expert system.(3) the introduction of fault diagnosis expert system(4) intelligent digital servo drives. Can automatically identify the load and automatically adjust the parameters of the drive system to get the best state of operation.Third, the choice of numerical control system1. Open-loop systemThe system's servo-driven device is a stepper motor, power stepper motors, electro-hydraulic pulse motors. This system does not require position and velocity feedback, displacement accuracy depends mainly on the angular displacement precision stepper motor and gear drive components such as precision screw, so displacement of low accuracy. But the system is simple, debugging easy maintenance, reliable, low cost, easily converted successfully.2. Closed-loop systemThe system consists of grating, sensor position detection device synchronization, etc. The actual measured position signal fed back to the computer, compared with a given value, the difference between the two amplification and transformation, driving the implementing agencies in order to eliminate bias. The system complexity, high cost and strict temperature requirements on the environment. But thesystem of high precision, speed and big power. According to technological requirements and decide whether to adopt.3. Semi-closed-loop systemSemi-closed-loop system detects components installed in the middle of transmission parts, the indirect measurement of the location of the implementation of parts. It can only compensate for part of the components within the system loop error, and therefore its more accurate than the accuracy of closed-loop system is low, but its structure and debugging as compared with the closed-loop system is simple.Current production numerical control system are more companies and manufacturers, foreign companies such as Siemens of Germany, Japan, Fanuc, Inc.; domestic Everest companies such as China, the Beijing Aerospace CNC System Corporation, Huazhong CNC CNC high-grade corporate and Shenyang National Engineering Research Center. Select CNC systems are mainly based on numerical control after transformation to be achieved in a variety of precision machine tools, drive motor power and the user's requirements to determine. Fourth, the main steps CNC transformation1. Determination of rehabilitation programs(1) Mechanical and Electrical Repair transformation combined.Generally speaking, in need of transformation of electrical machines, are in need of mechanical repair. To determine repair requirements, scope and content; have to ascertain the electrical modification of the mechanical structure in need of transformation requirements and content; but also determine the transformation of electrical and mechanical repair, reconstruction staggered between the time requirements. Mechanical properties of intact are electrical transformation success.(2) the easier issues first, after the first partial overall. Determine the transformation step, the whole electrical part of the transformation should be divided into several sub-systems, the basic shape of various systems to be connected after the completion of the whole system work. In each subsystem, we should do first the less technical, workload the larger work, and then do a technical high, requiring fine work, can focus people's attention to key areas.(3) selection system under conditions of use. For the transformation of the object to determine its environment and conditions, which the selection of electrical system protection, anti-jamming, self-cooling and air filtering performance can provide the correct basis. Electrical system options must also be considered mature products, their performance should be reasonable and practical, there are spare parts to provide maintenance support, features a number of years to meetthe current and future development requirements.(4) The implementation and responsibilities of personnel involved in reconstruction.(5) The transformation of the determination of the scope and cycle.2. Transformation of the technical preparation(1) mechanical parts ready. In line with the transformation of mechanical electrical repairs should be completed in advance. The same time, be demolished and replaced and processing should be part of such advance planning is necessary to properly interface with the entire transformation.(2) The electrical information on the new system to digest.(3) The conversion of the old system interface design. According to the scope of each of the different equipment modification required to pre-designed interface, part of the conversion, if the entire transformation should be designed to convert mechanical and electrical interfaces, operation panel control and configuration, the Internet part of the contact, parameter measurement, the maintenance and so on. Require the operation and maintenance easy and reasonable, alignments, fluent, primary and secondary connection point less electrical interference with the strength of the smallest, with an appropriate margin and so on. Local transformation, but also need to consider the performance of the system match theold and new, the voltage polarity and size of change, the installation location, digital-analog conversion, etc., if necessary, need to create their own interfaces.(4) operation and programming staff technical training. ①training should cover the new control panel configuration, function and meaning of the instructions; ②the scope of the new system features, use, and the difference between the old system; ③maintenance requirements; ④programming standards and automated programming and more. Focused understood, grasp operating instructions and programming instructions.(5) Debugging steps and acceptance criteria for the determination. Debugging should be done by the project leader carried out with the others. Debugging step can be from simple to complex, from small to large, from outside to inside, you can also after the first local situation, the whole system after the first subsystem. The development of acceptance criteria must be realistic, too high or too low a standard will have a negative impact on the transformation.3. The implementation of reform(1) The overall maintenance of the machine. The long-term use of the original machine, you need to conduct a comprehensive maintenance. Secondly, the response to machine tools to make achange before the geometric accuracy, dimensional accuracy of measurement, and for the record. In this way pairs of reference to guide the transformation of the role, but also in the transformation of the end for comparison analysis.(2) to retain the electrical adjustment of some of the best. If the electrical system as part of the transformation, in turn, should retain the parts of the maintenance and optimization adjustments, such as high power part of the spare parts replacement, electrical maintenance, drying transformer insulation, pollution, cleaning, ventilation and cooling equipment cleaning, servo Drive optimization adjustments, update aging wires and cables, connectors and other fastening. Only the electrical part of the reservation and do excellent optimization adjustment, in order to ensure that transformed the machine tool have lower failure rates.(3) The original systems were dismantled. The removal of the original system must be controlled carefully to the original drawings in time to make mark in the drawings to prevent the omission or been demolished. In the process of demolition will find some of the new system design in the gaps, it is timely to add and correction. Removed the system should be properly safeguarded in case of unsuccessful reconstruction resume use. There is a definite value, and can be used for spare parts.(4) reasonable arrangements for the location and wiring the new system. Connection must be a clear division of labor, there is one person review the inspection to ensure that the connection process specifications, diameter suitable, correct, reliable and beautiful. (5) debugging. Debug must be pre-established procedures and requirements. Debugging the first to test the safety protection system sensitivity, personal and equipment to prevent accidents. Debugging the site must be clean; the moving coordinate extension units at the center of the whole trip; be able to load test, the first no-load after load; can simulate the experiment, the first real action after simulated; be manual, first manually and automatically.4. Acceptance and post-work(1) The mechanical properties of machine tool acceptance. Machine tool should meet the requirements of the mechanical properties, geometric accuracy should be within the limits prescribed.(2) The electrical control functions and control accuracy and acceptance. The various functions of electrical control actions must meet the normal, sensitive and reliable. Control precision application system itself functions (such as step size, etc.) and standard measuring apparatus (such as laser interferometer, coordinate measuring machine, etc.) control checks, to reach within a range. Should also be modified before the machine with the functions andaccuracy to make comparison, access to quantifiable indicators of difference.(3) The test piece cutting and acceptance. Can refer to the relevant domestic and international standards for CNC cutting specimens, in a qualified operator, the programmer with the trial under the cut. Specimen cutting machine tools can be acceptance of stiffness, cutting force, noise, motion trajectory, related actions, are generally not suitable for specimen use of a product part.(4), drawings, information and acceptance. Machine transformation finished, should be promptly drawings, data, transform the file summary, collate, transfer into the file. This is the future and stable operation of the equipment is very important.(5) Summary and improve.5, numerical examples of reconstruction1. Milling machine with the Siemens 810M transformation X53In 1998, the company invested 200,000 yuan, with Germany's Siemens 810M CNC system, 611A AC servo drive system on the company's X53 model of a milling machine to X, Y, Z three-axis numerical control transformation. Retained the original spindle system and cooling system. -Axis transformation of a ball screw used in the machinery and gear transmission mechanism. Thetransformation of work includes mechanical design, electrical design, PLC program preparation and debugging, machine tool repair, machine installation and debugging. After transformation, milling, processing and effective travel X, Y, Z axis respectively, 880mm, 270mm, 280mm; maximum speed of X, Y, Z axis respectively, 5 000mm/min, 1 500mm/min, 800mm/min; point moving speed of X, Y, Z axis respectively 3 000mm/min, 1 000mm/min, 500 mm / min; machining accuracy of ± 0.001 mm. Machine tools, coordinate linkage to be completed by a variety of complex curve or surface processing.2. GSK980T and stepper drive system with the transformation ofC6140 latheIn 1999, the company invested 8 million yuan, with Guangzhou CNC Equipment Factory production GSK980T numerical control system, DY3 hybrid stepper drive unit on the company's a longerC6140 lathe X, Z 2-axis transform. Retained the original spindle system and cooling system. Transformation of two-axis ball screw in the machinery used, and synchronous transmission. The transformation of work includes mechanical design, electrical design, machine overhaul and machine installation and debugging. Lathe After the transformation, processing and effective stroke X, Z axis respectively, 390mm, 1400mm; maximum speed X, Z axisrespectively, 1 200mm/min, 3 000mm/min; jog speed 400mm/min; point moving fast X, Z-axis respectively, 1 200mm/min, 3000mm/min; machine smallest mobile unit 0.001mm.6, numerical transformation of the issues and recommendations1. Transformation problems in NCCNC machine tools through several transformation and found work, there are also many problems, mainly reflected in: (a) The departments, developers uncertain functions, organizational chaos, a serious impact on progress in the transformation; (2) to develop the work process and plans are mostly developed rule of thumb, less reasonable; (3) the training of relevant personnel is not in place, resulting in machine tool technology officers will not be modified after programming, the operator of the machine operator unskilled and so on.2. Transformation of the proposed NC(1) is responsible for transformation of the staff responsibilities of clear penalties and rewards, fully mobilize the enthusiasm of the staff; train a batch of high-quality applications and maintenance personnel, training for selected officers to go out and learn the advanced technologies;(2) To focus on users, maintenance of CNC system of technicaltraining, the establishment of numerical control technology at home and abroad resource library. The establishment of technical data files, do the work of spare parts.分析数控机床改造为了我国民营企业的生存与发展,提高数控机床的速度是必要的。

数控加工外文翻译文献

数控加工外文翻译文献

数控加工外文翻译文献(文档含中英文对照即英文原文和中文翻译)原文:Basic Machining Operations and CuttingTechnologyBasic Machining OperationsMachine tools have evolved from the early foot-powered lathes of the Egyptians and John Wilkinson's boring mill. They are designed to provide rigid support for both the workpiece and the cutting tool and can precisely control their relative positions and the velocity of the tool with respect to the workpiece. Basically, in metal cutting, a sharpened wedge-shaped tool removes a rather narrow strip of metal from the surface of a ductile workpiece in the form of a severely deformed chip. The chip is a waste product that is considerably shorter than the workpiece from which it came but with a corresponding increase in thickness of the uncut chip. The geometrical shape of workpiece depends on the shape of the tool and its path during the machining operation.Most machining operations produce parts of differing geometry. If a rough cylindrical workpiece revolves about a central axis and the tool penetrates beneath its surface and travels parallel to the center of rotation, a surface of revolution is produced, and the operation is called turning. If a hollow tube is machined on the inside in a similar manner, the operation is called boring. Producing an external conical surface uniformly varying diameter is called taper turning, if the tool point travels in a path of varying radius, a contoured surface like that of a bowling pin can be produced; or, if the piece is short enough and the support is sufficiently rigid, a contoured surface could be produced by feeding a shaped tool normal to the axis of rotation. Short tapered or cylindrical surfaces could also be contour formed.Flat or plane surfaces are frequently required. They can be generated by radial turning or facing, in which the tool point moves normal to the axis of rotation. In other cases, it is more convenient to hold the workpiece steady andreciprocate the tool across it in a series of straight-line cuts with a crosswise feed increment before each cutting stroke. This operation is called planning and is carried out on a shaper. For larger pieces it is easier to keep the tool stationary and draw the workpiece under it as in planning. The tool is fed at each reciprocation. Contoured surfaces can be produced by using shaped tools.Multiple-edged tools can also be used. Drilling uses a twin-edged fluted tool for holes with depths up to 5 to 10 times the drill diameter. Whether the drill turns or the workpiece rotates, relative motion between the cutting edge and the workpiece is the important factor. In milling operations a rotary cutter with a number of cutting edges engages the workpiece. Which moves slowly with respect to the cutter. Plane or contoured surfaces may be produced, depending on the geometry of the cutter and the type of feed. Horizontal or vertical axes of rotation may be used, and the feed of the workpiece may be in any of the three coordinate directions.Basic Machine ToolsMachine tools are used to produce a part of a specified geometrical shape and precise I size by removing metal from a ductile material in the form of chips. The latter are a waste product and vary from long continuous ribbons of a ductile material such as steel, which are undesirable from a disposal point of view, to easily handled well-broken chips resulting from cast iron. Machine tools perform five basic metal-removal processes: I turning, planning, drilling, milling, and grinding. All other metal-removal processes are modifications of these five basic processes. For example, boring is internal turning; reaming, tapping, and counter boring modify drilled holes and are related to drilling; bobbing and gear cutting are fundamentally milling operations; hack sawing and broaching are a form of planning and honing; lapping, super finishing. Polishing and buffing are variants of grinding or abrasive removal operations. Therefore, there are only four types of basic machine tools, which use cuttingtools of specific controllable geometry: 1. lathes, 2. planers, 3. drilling machines, and 4. milling machines. The grinding process forms chips, but the geometry of the abrasive grain is uncontrollable.The amount and rate of material removed by the various machining processes may be I large, as in heavy turning operations, or extremely small, as in lapping or super finishing operations where only the high spots of a surface are removed.A machine tool performs three major functions: 1. it rigidly supports the workpiece or its holder and the cutting tool; 2. it provides relative motion between the workpiece and the cutting tool; 3. it provides a range of feeds and speeds usually ranging from 4 to 32 choices in each case.Speed and Feeds in MachiningSpeeds, feeds, and depth of cut are the three major variables for economical machining. Other variables are the work and tool materials, coolant and geometry of the cutting tool. The rate of metal removal and power required for machining depend upon these variables.The depth of cut, feed, and cutting speed are machine settings that must be established in any metal-cutting operation. They all affect the forces, the power, and the rate of metal removal. They can be defined by comparing them to the needle and record of a phonograph. The cutting speed (V) is represented by the velocity of- the record surface relative to the needle in the tone arm at any instant. Feed is represented by the advance of the needle radially inward per revolution, or is the difference in position between two adjacent grooves. The depth of cut is the penetration of the needle into the record or the depth of the grooves.Turning on Lathe CentersThe basic operations performed on an engine lathe are illustrated. Those operations performed on external surfaces with a single point cutting tool arecalled turning. Except for drilling, reaming, and lapping, the operations on internal surfaces are also performed by a single point cutting tool.All machining operations, including turning and boring, can be classified as roughing, finishing, or semi-finishing. The objective of a roughing operation is to remove the bulk of the material as rapidly and as efficiently as possible, while leaving a small amount of material on the work-piece for the finishing operation. Finishing operations are performed to obtain the final size, shape, and surface finish on the workpiece. Sometimes a semi-finishing operation will precede the finishing operation to leave a small predetermined and uniform amount of stock on the work-piece to be removed by the finishing operation.Generally, longer workpieces are turned while supported on one or two lathe centers. Cone shaped holes, called center holes, which fit the lathe centers are drilled in the ends of the workpiece-usually along the axis of the cylindrical part. The end of the workpiece adjacent to the tailstock is always supported by a tailstock center, while the end near the headstock may be supported by a headstock center or held in a chuck. The headstock end of the workpiece may be held in a four-jaw chuck, or in a type chuck. This method holds the workpiece firmly and transfers the power to the workpiece smoothly; the additional support to the workpiece provided by the chuck lessens the tendency for chatter to occur when cutting. Precise results can be obtained with this method if care is taken to hold the workpiece accurately in the chuck.Very precise results can be obtained by supporting the workpiece between two centers. A lathe dog is clamped to the workpiece; together they are driven by a driver plate mounted on the spindle nose. One end of the Workpiece is mecained;then the workpiece can be turned around in the lathe to machine the other end. The center holes in the workpiece serve as precise locating surfaces as well as bearing surfaces to carry the weight of the workpiece and to resist the cutting forces. After the workpiece has been removed from the lathe for any reason, the center holes will accurately alignthe workpiece back in the lathe or in another lathe, or in a cylindrical grinding machine. The workpiece must never be held at the headstock end by both a chuck and a lathe center. While at first thought this seems like a quick method of aligning the workpiece in the chuck, this must not be done because it is not possible to press evenly with the jaws against the workpiece while it is also supported by the center. The alignment provided by the center will not be maintained and the pressure of the jaws may damage the center hole, the lathe center, and perhaps even the lathe spindle. Compensating or floating jaw chucks used almost exclusively on high production work provide an exception to the statements made above. These chucks are really work drivers and cannot be used for the same purpose as ordinary three or four-jaw chucks.While very large diameter workpieces are sometimes mounted on two centers, they are preferably held at the headstock end by faceplate jaws to obtain the smooth power transmission; moreover, large lathe dogs that are adequate to transmit the power not generally available, although they can be made as a special. Faceplate jaws are like chuck jaws except that they are mounted on a faceplate, which has less overhang from the spindle bearings than a large chuck would have.Introduction of MachiningMachining as a shape-producing method is the most universally used and the most important of all manufacturing processes. Machining is a shape-producing process in which a power-driven device causes material to be removed in chip form. Most machining is done with equipment that supports both the work piece and cutting tool although in some cases portable equipment is used with unsupported workpiece.Low setup cost for small Quantities. Machining has two applications in manufacturing. For casting, forging, and press working, each specific shape to be produced, even one part, nearly always has a high tooling cost. The shapes that may he produced by welding depend to a large degree on the shapes ofraw material that are available. By making use of generally high cost equipment but without special tooling, it is possible, by machining; to start with nearly any form of raw material, so tong as the exterior dimensions are great enough, and produce any desired shape from any material. Therefore .machining is usually the preferred method for producing one or a few parts, even when the design of the part would logically lead to casting, forging or press working if a high quantity were to be produced.Close accuracies, good finishes. The second application for machining is based on the high accuracies and surface finishes possible. Many of the parts machined in low quantities would be produced with lower but acceptable tolerances if produced in high quantities by some other process. On the other hand, many parts are given their general shapes by some high quantity deformation process and machined only on selected surfaces where high accuracies are needed. Internal threads, for example, are seldom produced by any means other than machining and small holes in press worked parts may be machined following the press working operations.Primary Cutting ParametersThe basic tool-work relationship in cutting is adequately described by means of four factors: tool geometry, cutting speed, feed, and depth of cut.The cutting tool must be made of an appropriate material; it must be strong, tough, hard, and wear resistant. The tool s geometry characterized by planes and angles, must be correct for each cutting operation. Cutting speed is the rate at which the work surface passes by the cutting edge. It may be expressed in feet per minute.For efficient machining the cutting speed must be of a magnitude appropriate to the particular work-tool combination. In general, the harder the work material, the slower the speed.Feed is the rate at which the cutting tool advances into the workpiece. "Where the workpiece or the tool rotates, feed is measured in inches perrevolution. When the tool or the work reciprocates, feed is measured in inches per stroke, Generally, feed varies inversely with cutting speed for otherwise similar conditions.The depth of cut, measured inches is the distance the tool is set into the work. It is the width of the chip in turning or the thickness of the chip in a rectilinear cut. In roughing operations, the depth of cut can be larger than for finishing operations.The Effect of Changes in Cutting Parameters on Cutting TemperaturesIn metal cutting operations heat is generated in the primary and secondary deformation zones and these results in a complex temperature distribution throughout the tool, workpiece and chip. A typical set of isotherms is shown in figure where it can be seen that, as could be expected, there is a very large temperature gradient throughout the width of the chip as the workpiece material is sheared in primary deformation and there is a further large temperature in the chip adjacent to the face as the chip is sheared in secondary deformation. This leads to a maximum cutting temperature a short distance up the face from the cutting edge and a small distance into the chip.Since virtually all the work done in metal cutting is converted into heat, it could be expected that factors which increase the power consumed per unit volume of metal removed will increase the cutting temperature. Thus an increase in the rake angle, all other parameters remaining constant, will reduce the power per unit volume of metal removed and the cutting temperatures will reduce. When considering increase in unreformed chip thickness and cutting speed the situation is more complex. An increase in undeformed chip thickness tends to be a scale effect where the amounts of heat which pass to the workpiece, the tool and chip remain in fixed proportions and the changes in cutting temperature tend to be small. Increase in cutting speed; however, reduce the amount of heat which passes into the workpiece and this increase the temperature rise of the chip m primary deformation. Further, the secondarydeformation zone tends to be smaller and this has the effect of increasing the temperatures in this zone. Other changes in cutting parameters have virtually no effect on the power consumed per unit volume of metal removed and consequently have virtually no effect on the cutting temperatures. Since it has been shown that even small changes in cutting temperature have a significant effect on tool wear rate it is appropriate to indicate how cutting temperatures can be assessed from cutting data.The most direct and accurate method for measuring temperatures in high -speed-steel cutting tools is that of Wright &. Trent which also yields detailed information on temperature distributions in high-speed-steel cutting tools. The technique is based on the metallographic examination of sectioned high-speed-steel tools which relates microstructure changes to thermal history.Trent has described measurements of cutting temperatures and temperature distributions for high-speed-steel tools when machining a wide range of workpiece materials. This technique has been further developed by using scanning electron microscopy to study fine-scale microstructure changes arising from over tempering of the tempered martens tic matrix of various high-speed-steels. This technique has also been used to study temperature distributions in both high-speed -steel single point turning tools and twist drills.Wears of Cutting ToolDiscounting brittle fracture and edge chipping, which have already been dealt with, tool wear is basically of three types. Flank wear, crater wear, and notch wear. Flank wear occurs on both the major and the minor cutting edges. On the major cutting edge, which is responsible for bulk metal removal, these results in increased cutting forces and higher temperatures which if left unchecked can lead to vibration of the tool and workpiece and a condition where efficient cutting can no longer take place. On the minor cutting edge, which determines workpiece size and surface finish, flank wear can result in anoversized product which has poor surface finish. Under most practical cutting conditions, the tool will fail due to major flank wear before the minor flank wear is sufficiently large to result in the manufacture of an unacceptable component.Because of the stress distribution on the tool face, the frictional stress in the region of sliding contact between the chip and the face is at a maximum at the start of the sliding contact region and is zero at the end. Thus abrasive wear takes place in this region with more wear taking place adjacent to the seizure region than adjacent to the point at which the chip loses contact with the face. This result in localized pitting of the tool face some distance up the face which is usually referred to as catering and which normally has a section in the form of a circular arc. In many respects and for practical cutting conditions, crater wear is a less severe form of wear than flank wear and consequently flank wear is a more common tool failure criterion. However, since various authors have shown that the temperature on the face increases more rapidly with increasing cutting speed than the temperature on the flank, and since the rate of wear of any type is significantly affected by changes in temperature, crater wear usually occurs at high cutting speeds.At the end of the major flank wear land where the tool is in contact with the uncut workpiece surface it is common for the flank wear to be more pronounced than along the rest of the wear land. This is because of localised effects such as a hardened layer on the uncut surface caused by work hardening introduced by a previous cut, an oxide scale, and localised high temperatures resulting from the edge effect. This localised wear is usually referred to as notch wear and occasionally is very severe. Although the presence of the notch will not significantly affect the cutting properties of the tool, the notch is often relatively deep and if cutting were to continue there would be a good chance that the tool would fracture.If any form of progressive wear allowed to continue, dramatically and the tool would fail catastrophically, i. e. the tool would be no longer capable ofcutting and, at best, the workpiece would be scrapped whilst, at worst, damage could be caused to the machine tool. For carbide cutting tools and for all types of wear, the tool is said to have reached the end of its useful life long before the onset of catastrophic failure. For high-speed-steel cutting tools, however, where the wear tends to be non-uniform it has been found that the most meaningful and reproducible results can be obtained when the wear is allowed to continue to the onset of catastrophic failure even though, of course, in practice a cutting time far less than that to failure would be used. The onset of catastrophic failure is characterized by one of several phenomena, the most common being a sudden increase in cutting force, the presence of burnished rings on the workpiece, and a significant increase in the noise level. Mechanism of Surface Finish ProductionThere are basically five mechanisms which contribute to the production of a surface which have been machined. These are:(l) The basic geometry of the cutting process. In, for example, single point turning the tool will advance a constant distance axially per revolution of the workpiecc and the resultant surface will have on it, when viewed perpendicularly to the direction of tool feed motion, a series of cusps which will have a basic form which replicates the shape of the tool in cut.(2) The efficiency of the cutting operation. It has already been mentioned that cutting with unstable built-up-edges will produce a surface which contains hard built-up-edge fragments which will result in a degradation of the surface finish. It can also be demonstrated that cutting under adverse conditions such as apply when using large feeds small rake angles and low cutting speeds, besides producing conditions which lead to unstable built-up-edge production, the cutting process itself can become unstable and instead of continuous shear occurring in the shear zone, tearing takes place, discontinuous chips of uneven thickness are produced, and the resultant surface is poor. Thissituation is particularly noticeable when machining very ductile materials such as copper and aluminum.(3) The stability of the machine tool. Under some combinations of cutting conditions; workpiece size, method of clamping ,and cutting tool rigidity relative to the machine tool structure, instability can be set up in the tool which causes it to vibrate. Under some conditions this vibration will reach and maintain steady amplitude whilst under other conditions the vibration will built up and unless cutting is stopped considerable damage to both the cutting tool and workpiece may occur. This phenomenon is known as chatter and in axial turning is characterized by long pitch helical bands on the workpiece surface and short pitch undulations on the transient machined surface.(4)The effectiveness of removing swarf. In discontinuous chip production machining, such as milling or turning of brittle materials, it is expected that the chip (swarf) will leave the cutting zone either under gravity or with the assistance of a jet of cutting fluid and that they will not influence the cut surface in any way. However, when continuous chip production is evident, unless steps are taken to control the swarf it is likely that it will impinge on the cut surface and mark it. Inevitably, this marking besides looking.(5)The effective clearance angle on the cutting tool. For certain geometries of minor cutting edge relief and clearance angles it is possible to cut on the major cutting edge and burnish on the minor cutting edge. This can produce a good surface finish but, of course, it is strictly a combination of metal cutting and metal forming and is not to be recommended as a practical cutting method. However, due to cutting tool wear, these conditions occasionally arise and lead to a marked change in the surface characteristics.Limits and TolerancesMachine parts are manufactured so they are interchangeable. In other words, each part of a machine or mechanism is made to a certain size and shape so will fit into any other machine or mechanism of the same type. Tomake the part interchangeable, each individual part must be made to a size that will fit the mating part in the correct way. It is not only impossible, but also impractical to make many parts to an exact size. This is because machines are not perfect, and the tools become worn. A slight variation from the exact size is always allowed. The amount of this variation depends on the kind of part being manufactured. For examples part might be made 6 in. long with a variation allowed of 0.003 (three-thousandths) in. above and below this size. Therefore, the part could be 5.997 to 6.003 in. and still be the correct size. These are known as the limits. The difference between upper and lower limits is called the tolerance.A tolerance is the total permissible variation in the size of a part.The basic size is that size from which limits of size arc derived by the application of allowances and tolerances.Sometimes the limit is allowed in only one direction. This is known as unilateral tolerance.Unilateral tolerancing is a system of dimensioning where the tolerance (that is variation) is shown in only one direction from the nominal size. Unilateral tolerancing allow the changing of tolerance on a hole or shaft without seriously affecting the fit.When the tolerance is in both directions from the basic size it is known as a bilateral tolerance (plus and minus).Bilateral tolerancing is a system of dimensioning where the tolerance (that is variation) is split and is shown on either side of the nominal size. Limit dimensioning is a system of dimensioning where only the maximum and minimum dimensions arc shown. Thus, the tolerance is the difference between these two dimensions.Surface Finishing and Dimensional ControlProducts that have been completed to their proper shape and size frequently require some type of surface finishing to enable them tosatisfactorily fulfill their function. In some cases, it is necessary to improve the physical properties of the surface material for resistance to penetration or abrasion. In many manufacturing processes, the product surface is left with dirt .chips, grease, or other harmful material upon it. Assemblies that are made of different materials, or from the same materials processed in different manners, may require some special surface treatment to provide uniformity of appearance.Surface finishing may sometimes become an intermediate step processing. For instance, cleaning and polishing are usually essential before any kind of plating process. Some of the cleaning procedures are also used for improving surface smoothness on mating parts and for removing burrs and sharp corners, which might be harmful in later use. Another important need for surface finishing is for corrosion protection in a variety of: environments. The type of protection procedure will depend largely upon the anticipated exposure, with due consideration to the material being protected and the economic factors involved.Satisfying the above objectives necessitates the use of main surface-finishing methods that involve chemical change of the surface mechanical work affecting surface properties, cleaning by a variety of methods, and the application of protective coatings, organic and metallic.In the early days of engineering, the mating of parts was achieved by machining one part as nearly as possible to the required size, machining the mating part nearly to size, and then completing its machining, continually offering the other part to it, until the desired relationship was obtained. If it was inconvenient to offer one part to the other part during machining, the final work was done at the bench by a fitter, who scraped the mating parts until the desired fit was obtained, the fitter therefore being a 'fitter' in the literal sense. J It is obvious that the two parts would have to remain together, and m the event of one having to be replaced, the fitting would have to be done all over again. Inthese days, we expect to be able to purchase a replacement for a broken part, and for it to function correctly without the need for scraping and other fitting operations.When one part can be used 'off the shelf' to replace another of the same dimension and material specification, the parts are said to be interchangeable.A system of interchangeability usually lowers the production costs as there is no need for an expensive, 'fiddling' operation, and it benefits the customer in the event of the need to replace worn parts.Automatic Fixture DesignTraditional synchronous grippers for assembly equipment move parts to the gripper centre-line, assuring that the parts will be in a known position after they arc picked from a conveyor or nest. However, in some applications, forcing the part to the centre-line may damage cither the part or equipment. When the part is delicate and a small collision can result in scrap, when its location is fixed by a machine spindle or mould, or when tolerances are tight, it is preferable to make a gripper comply with the position of the part, rather than the other way around. For these tasks, Zaytran Inc. Of Elyria, Ohio, has created the GPN series of non- synchronous, compliant grippers. Because the force and synchronizations systems of the grippers are independent, the synchronization system can be replaced by a precision slide system without affecting gripper force. Gripper sizes range from 51b gripping force and 0.2 in. stroke to 40Glb gripping force and 6in stroke. GrippersProduction is characterized by batch-size becoming smaller and smaller and greater variety of products. Assembly, being the last production step, is particularly vulnerable to changes in schedules, batch-sizes, and product design. This situation is forcing many companies to put more effort into extensive rationalization and automation of assembly that was previouslyextensive rationalization and automation of assembly that was previously the case. Although the development of flexible fixtures fell。

数控立式车削中心数控化改造——外文文献翻译、中英文翻译

数控立式车削中心数控化改造——外文文献翻译、中英文翻译

毕业设计(论文)外文翻译题目数控立式车削中心数控化改造专业名称班级学号学生姓名指导教师日期20** 年 3 月10 日外文原文:Vertical Turning Center of NCNew SINUMERIK 802D CNC system on the use of more than 10 years of SKIQ16 CNC B Vertical Turning Center of NC, NC Machine Tool powerful features greatly broadened the scope of machining parts, and better ensuring the processing of parts the consistency and quality of products. This article was the second SINUMERIK NC application essay activities and the transformation of a prize-second prize.KIQ16 CNC B Vertical Turning Center in the Czech HULIN companies in the 1990s manufacture, use FANUC-BASK 6T CNC system. Since the machine had been in use for more than 10 years, and the NC system upgrading, BASK 6T-FANUC CNC system has been shutdown, system board of aging, expensive spare parts. A new CNC machine tools to transform the system is imperative so that the machine can restore vitality, and give better play to the potential of machine tools.Transformation programme developmentThe original full-featured machine, including spindle (table) and the rotation axis milling campaign, X, Z-axis coordinates of movement, 15 knives in a knife library systems, and such as the cooling system, hydraulic system, lubrication system , Paixie system functional machine. Spindle axis and milling by DC and DC motor speed regulator. X and Z-axis also coordinates by DC servo motor and DC servo governor. The knife used ordinary three-phase asynchronous AC motor from the five binary cam positioning. The mechanical part of the machine all good mechanical properties of stability, accuracy fair and normal hydraulic system, the part of the capital remain unchanged.NC system and the replacement of electrical control part, by SIEMENS SINUMERIK 802D CNC system. X and Z axes and knives coordinates the servo drive system uses SIIMODRIVE 611UE variable frequency drive system and a FK7 servo motor, encoder pulse chosen as a location detection devices, digital servo drive system to achieve closed-loop control. And milling spindle axis drive system by the British company's 590 + Eurotherm Series DC motor speed control device. Machine control of other electrical lines, the replacement of electrical control devices to ensurethat all kinds of machine control function and operation of the realization of the electrical control machine tools guarantee a long-term reliable work.Apart from increasing MCP machine control panel, we must also re-designed machine operator panel with all types of machine function buttons and lights. NC system and the servo drive system coordinatesSIEMENS SINUMERIK 802D CNC system is all CNC, PLC, HMI and communications tasks integration, is based on the NC system of PROFIBUS. Maintenance-free hardware integration PROFIBUS interface used to drive and I / O module and installed a speed of the operation panel. SINUMERIK 802D CNC control system X, Z axes and knives to the three figures into a spindle axis and. The machine used two I / O modules and machine operator panel PP72/48 MCP. TOOLBOX 802D use in PROGRAMMING TOOL PLC 802 software development PLC control procedures, call the subroutine library PLC SBR32 PLC-INI PLC initialization, SBR33 EMG-STOP exigency stop processing, transmission SBR34 MCP-802D machine control panel corresponding I / O status, NCK-SBR38 MCP MCP machine control panel signal, signal sent to the operation panel HMI NCK interface, SBR39 HANDWHL from the operation panel HMI in the machine coordinates or workpiece coordinate system selection hand wheel, SBR40 AXIS-CTL Feed spindle axis and enable control. The subroutine is the standard lathe control procedures, and so different from the actual situation of the machine, the digital knife-axis, an increase of the number of digital axis. In the machine control panel and feed axis and the spindle can control subroutine will be done in certain modifications. Vertical Turning Center unlike ordinary horizontal lathe, coordinates a different direction, it is also necessary to do subroutine amended accordingly.SIIMODRIVE 611UE variable frequency drive system is a function of the drive system can be configured with SINUMERIK 802D CNC system constitutes an ideal combination. SIIMODRIVE 611UE variable frequency drive system in the machine to meet the dynamic response and speed adjustment range and rotation accuracy characteristics of the requirement to use modular design can be optimized to best independent state. Debugging can drive on a PC using SimoCom U or use of the front of the driver modules for display and keyboard. SimoCom U can be set using drivesand motors and power modules matching the basic parameters of actual under servo motor drive mechanical parts, the SIIMODRIVE 611UE speed controller for automatic optimization of the parameters; can monitor the operational status of drivers, including actual motor current and the actual torque.axis milling spindle and drive systemAnd milling spindle axis drive system using the British company's 590 + Eurotherm Series DC motor speed control device. 590 + series of DC motor speed control device as supporting and control equipment installed in the standard box components and design. AC 380V control devices using the standard three-phase voltage, providing DC output voltage and current for the armature and exciting, applicable to DC Motor control and permanent magnet motor.590 + series of DC motor speed device is used to achieve 32-bit microprocessor, has many advanced features: complex control algorithms; standard software modules and software configuration can control circuit integration of the serial link, and NC transmission devices or other communications systems, advanced to a process system. Axis milling spindle motor and not replaced, the original analog volume control. The spindle motor and non-spindle between 1:1 Direct Connect, spindle SIEMENS installed on the 5000 line TTL pulse incremental encoder. SIIMODRIVE 611UE bus will address the biaxial 12 A feed channel module with the spindle, set a stack axis. Through the SINUMERIK 802D CNC system parameter settings, the use of SimoCom U driver debugging tools adjustment SIIMODRIVE 611UE bus configuration parameters and analog output, analog output interface for a given output spindle speed (±10V), digital Output can be used to simulate the spindle control, WSG interface used to connect a spindle speed encoder feedback, and complete control of spindle configuration.knife Library Systemknife because the original system used for general motors, mechanical transmission ratio 1:360. The mechanical structure of special knives, knife disc in the vertical Z-axis ram, its direction and the B-axis rotation direction of the same. After transformation, using SIIMODRIVE 611UE and a variable frequency drive system FK7 servo motor, a knife to the NC coordinate axis, as increased pulse encoderposition detection devices, digital servo drive system to achieve closed-loop control. The removal of the original five binary cam positioning mechanism. As the knife after the full gravity knives, knife the disk can not achieve balance gravity. Although the movement can knife precise positioning, but the reasons for the deviation of the actual location, location is still used after positioning coordinates movement pin inserted accurate positioning methods.The special machine tool change process, with different vertical lathe general. PLC control ATC procedures are completed the following process: when the knife with X and Z-axis movement a safe place, Z axis, no knife, a machine tool relaxed state. PLC control manipulator out to promote vertical lathe tool to Z axis machine tool after the completion of that process finished with knives. Shirking knife, X and Z-axis movement a safe place, Z axis, a knife, a machine tool clamping state. PLC control mechanical hand outstretched, this tool to relax, manipulator driven vertical lathe tool retractable knife was back on, machine tool, knife disposal process is complete.SINUMERIK 802D CNC system support for the use of M code or user calls T code cycle can be used for machine tool exchange. By setting parameters M activation code, the use of the procedure called M06 fixed exchange cycle enforcement tool. Procedures for the preparation of users cycle through each algorithm to determine the knife knife-axis (B-axis) rotation angle, use of the definition of M ATC activation PLC logic. PLC NC system will be "read to prohibit" buy-signal so that the cycle of a fixed stop. ATC will be mechanical movements M code with a custom implementation of decomposition, such as: M12 dumping knives, M13 with knives. ATC completed, the PLC will be "read prohibits" reset signal so that the fixed cycle continue. In the fixed cycle shown in the preparation of CNC system prompts on the screen to ATC by step.Machine debuggingNC system connecting the various components after the completion of the installation, commissioning start PLC control procedures. Since the equipment is vertical lathe, unlike PLC subroutine library in the lathe applications, it must address the specific conditions of the machine to amend PLC subroutine.Set the knife for B-axis, and the standard procedures only X and Z axis, and the need to increase the B-axis in the MCP plus or minus adding B-axis direction to move the button, the need for SBR34, SBR38, SBR40 such as subroutine. Because it is vertical lathe, X, Z-axis direction to move the plus or minus key MCP and set different standards also needs to be revised. According to MCP on the machine need to design user-defined keys, such as hydraulic launch, hydraulic stop, relax beams, and light beams locking design MCP and machine operator panels PLC control procedures and debugging features to achieve. Fully tested by the use of the subroutine library of subroutines to ensure that the subroutine with the functions of PLC control procedures linked, are correct. Alarm users edit PLC design, machine parameters provided by setting the properties of each alarm. Machine set basic parameters include: PROFIBUS bus configuration, positioning servo drive module, the spindle axis position control and coordinate enable ratio and transmission parameters.In the machine undergone a series of adjustments, NC Machine Tools has basically can be in normal operation. But to make the whole system into the best running state, but also a system parameter optimization work.When the normal operation of the system as a whole, should also coordinate axis corresponding parameters such as optimal adjustment, such as: speed, gain, and the acceleration of the control parameters, in order to enable access to the best system of the state. In the normal operation of machine tools, machine tools should also mechanical parts, such as the vertical axis, the reverse gap, transmission precision measurement adjustments, the mechanical system to the best. Of course, the mechanical adjustments, should also fine-tune system parameters to enable the machine running in the best condition. When the part of the adjustment after the end of the machine through mechanical precision measurement, CNC machine tools needed for the position control system for precision compensation. Reverse clearance compensation for position feedback encoder mounted on the lead screw drive-head, although the slowdown in bins eliminate mechanical part of the reverse gap, but the reverse itself leadscrew gap still exists, the value of the corresponding input system parameters, each reverse operation, the system of compensation. Because long-termuse of the leadscrew wear, the location of the leadscrew pitch and will have a nominal value error, to improve positioning accuracy, the system parameters compensation. According to the production needs of users with the process of transforming machine tools, from SINUMERIK 802D CNC system for the analysis, design and implementation. At present, against the machine mechanical, electrical, various aspects of the system transformation, installation, commissioning work has been completed, samples were processed fully achieve the desired results. Machine Tool has been transformed into normal use, the progressive completion of a number of machining tasks. From the use of the machine running the state, the modified machine compared with the original machine, greatly enhancing the functionality, a high degree of automation. NC powerful features greatly broadened the scope of machining parts. Better guarantee the consistency of the parts processing, and product quality. At the same time a high degree of automation has greatly reduced the labor intensity operations workers, but in the operation of the overall quality of workers has also put forward higher requirements.From the machine operable, compact structure reasonable, displays, switches and indicator of the layout more suitable for the use of operators. At the same time increased by a small handheld unit operations, in order to operate in different state of the operation of a more appropriate choice of location. The hoisting of the entire operating system using TFT LCD, the window menu-operation, not only to reduce the operation buttons, but more simple and easy operation.After transformation, the machine can be maintained and enhanced. NC system for monitoring the work of the state control components and fault and displayed on the monitor in a timely manner, while PLC control applications, so that the whole machine tool control systems greatly simplify the circuit. All this makes machine fault detection and maintenance more convenient and rapid. Secondly, the need to be tested, liquid injection, fuel components are arranged in operation or maintenance staff accessible areas, which will help the day-to-day maintenance.After transformation, the machine reliability greatly improved. NC system, servo control systems, such as the various components of the system are highly integrated computer control system, which makes the whole machine tool control system itselfhas a high reliability. Design and Application of PLC, succeeded in bringing all of the control to the harmonization greatly simplifies the machine control circuit and the necessary components, and more conducive to improving the reliability of the whole system. The completion of the machine tool, not only for users to expand the scope of the processing machine, but also save a lot of money. The success of this transformation for the future transformation of the machine has accumulated a wealth of experience.译文:数控立式车削中心数控化改造用新型SINUMERIK 802D数控系统对使用10多年的SKIQ16 CNC B数控立式车削中心进行数控化改造,机床强大的数控功能极大地拓宽了机床加工零件的范围,更好地保证了零件加工的一致性和产品质量。

关于数控车床编程外文文献翻译中英文翻译外文翻译

关于数控车床编程外文文献翻译中英文翻译外文翻译

关于数控车床编程外文文献翻译、中英文翻译、外文翻译英文原文On the NC latheCNC machine tool numerical control machine tools (Computer numerical control machine tools) abbreviation, is provided with a program control system of automatic machine tools. The logic control system can deal with the control code or other symbolic instruction specified program, and decoding the digital code, said information carrier, through the numerical control device input. After processing by CNC device control signals, control the machine movements, by drawing the shape and size requirements, will be automatically processed by the parts.Features: CNC machine tool operation and monitoring of all completed inthe numericalcontrol unit, it is the brain of CNC machine tools. Compared with the general machine tools, CNC machine tools has the following characteristics:● the processing object adaptability, adapt to the characteristics of mold products such as a single production, provide the appropriate processing method for die and mould manufacturing; ● high machining accuracy, processing with stable quality; ● can coordinate linkage, processing complex shape parts;● machining parts change, only need to change the program, can save the preparation time of production;● the machine itself high precision, rigidity, can choose the am ount of processing good, high productivity (3~5 times as common machine);The machine is a high degree of automation, reducing labor intensity;● conducive to the production management modernization. The use of CNC machine tools and the standard code of digital information processing, information transmission, the use of computer control method, has laid the foundation for the integration of computer aided design, manufacturing and management;● on the operators of higher quality, higher demands for the repair ofthe technical staff;● high reliability.Composition: CNC machine tools in general by the input medium, man-machine interactive equipment, CNC equipment, feed servo drive system, spindle servo drive system, the auxiliary control device, feedback apparatus and adaptive control device etc.. [4] in NC machining, NC milling processing is the most complex, need to solve most problems. NC programming of NC line in addition to CNC milling, cutting, CNC EDM, CNC lathe, CNC grinding, each with its own characteristics, servo system is the role of the motion signal is convertedinto the machine moving parts from the numerical control device of pulse. Concrete has the following parts: the structure of CNC machine tools.Driver: he is driving parts of CNC machine tools, actuator, including spindle drive unit, feeding unit, spindle motor and feed motor. He through the electric or electro-hydraulic servo system to realize the spindle and feeddrive under the control of numerical control device. When several feed linkage, can complete the positioning, processing line, plane curve and space curve.The main performance (1) the main dimensions. (2) the spindle system. (3) feed system. (4) tool system.(5) electrical. Including the main motor, servo motor specifications and power etc.. (6) cooling system. Including the cooling capacity, cooling pump output. (7) dimensions. Expressed as length * width * height.Development trend of CNC lathe:High speed, precision, complex, intelligent and green is the general trend in the development of CNC machine tool technology, in recent years, made gratifying achievements in practicality and industrialization. Mainly in the:1 machine tool composite technology to further expand with the CNC machine tool technology, composite processing technology matures, including milling - car compound, car millingcompound, car - boring - drill - gear cutting compound, composite grinding, forming, composite processing, precision and efficiency of machining isgreatly improved. \processing factory\the development of compound processing machine tool is the trend of diversified.Intelligent technology 2 CNC machine tools have a new breakthrough, in the performance of NC system has been reflected more. Such as: automaticallyadjust the interference anti-collision function, after the power of workpiece automatically exit safety power-off protection function, machining parts detection and automatic compensation function of learning, high precisionmachining parts intelligent parameter selection function, process automatic elimination of machine vibration functions into the practical stage, intelligent upgrade the function of machine and quality.The 3 robots enable flexible combination of flexible combination of higher efficiency of robot and the host are widely used, make flexible line more flexible, extending the function, flexible line shorten further, more efficient. Robot and machining center, milling composite machine, grinder, gear processing machine tool, tool grinding machine, electric machine, sawing machine, punching machine, laser cutting machine, water cutting machine etc. various forms of flexible unit and flexible production line has already begun the application.4 precision machining technology has the machining precision of CNC metal cutting machine tools from the yarn in the original (0.01mm) up to micronlevel (0.001mm), some varieties has reached about 0.05 μ M. Micro cutting and grinding machining of ultra precision CNC machine tools, precision can reach about 0.05 μ m, shape precision can reach about 0.01 μ M. Special processing precision by using optical, electrical, chemical, energy can reach nanometer level (0.001 μ m). By optimizing the design of machine tool structure, machine tool parts of ultra precision machining and precision assembly, using high precision closed loop control andtemperature, vibration and other dynamic error compensation technology, improve the geometric accuracy of machine tool processing, reduce the shape of error, surface roughness, and into the submicron, nano super finishing tiThe 5 functional component to improve the performance of functional components are at a high speed, high precision, high power and intelligent direction, and obtain the mature application. A full digital AC servo motor and drive device, high technology content of the electric spindle, linear motor, torque motor, linear motion components with high performance, application of high precision spindle unit and other function parts, greatly improving the technical level of CNC machine tools.The feed drive system of CNC lathe: Effect of feed drive system,The feed drive system of CNC machine tools will be received pulse command issued by the numerical control system, and the amplification and conversion machine movements carry the expected movement.Two, the feeding transmission system requirementsIn order to guarantee the machining accuracy of NC machine tool is high,the feed drive system of transmission accuracy, sensitivity high (fast response), stable work, high stiffness and friction and inertia small, service life, and can remove the transmission gap. Category three, feed drive system 1, stepping motor servo system Generally used for NC machine tools. 2, DC servo motor servo systemPower is stable, but because of the brush, the wear resulting in use needto change. Generally used for middle-grade CNC machine tools. 3, AC servomotor servo systemThe application is extremely widespread, mainly used in high-end CNC machine tools. 4, the linear motor servo systemNo intermediate transmission chain, high precision, the feed speed, no length limit; but the poor heat dissipation, protection requirements are particularly high, mainly used for high-speed machine.Driving component four, feed system 1, the ball screw nut pairNC machining, the rotary motion into linear motion, so the use of screwnut transmissionmechanism. NC machine tools are commonly used on the ball screw, as shownin Figure 1-25, it can be a sliding friction into rolling friction, meet the basic requirements of the feed system to reduce friction. The transmissionside of high efficiency, small friction, and can eliminate the gap, no reverse air travel; but the manufacturing cost is high, can not lock, size is not too big, generally used for linear feed in small CNC machine tool. 2, rotary tableIn order to expand the scope of the process of NC machine tools, CNC machine tools in addition to make linear feed along the X, Y, Z three coordinate axes, often also need a circumferential feed movement around Y or Z axis. Circular feed motion of CNC machine tools in general by the rotary table to realize, for machining center, rotary table has become an indispensablepart of. Rotary table of commonly used CNC machine tools in the indexing table and NC rotary table. (1) indexing tableIndexing table can only finish dividing movement, not circular feed, it is in accordance with the instructions in the NC system, when indexing will work together with the workpiece rotation angle. When indexing can also use manual indexing. Provisions of indexing table is generally only rotary angle (such as 90, 60 and 45 degree). (2) NC rotary tableNC rotary table appearance similar to the indexing table, but the internal structure and function is not the same. The main function of the NC rotary table is based on the numerical control device sends command pulse signal, complete circumferential feed movement, various arc processing and surface processing, it can also be graduation work. 3, guideRail is an important part of feed drive system, is one of the basic elements of the structure of machine tool, rigidity, precision and accuracy of NC machine tool which determines to a large extent retention. At present, guide the NC machine tool are sliding rail, rolling guideway and hydrostatic guideway. (1) sliding guideSliding guide rail has the advantages of simple structure, easy manufacture, good stiffness, vibration resistance and high performance, widely used in CNC machine tools, the use of most metal plastic form, known as the plastic guide rail, as shown in figure 1-26.On characteristics of the plastic sliding guide: friction characteristicis good, good wear resistance, stable movement, good manufacturability, low speed. (2) rolling guideRolling guide is placed in the rail surface between the ball, roller or needle roller, roller, the rolling friction instead of sliding surface of the guide rail between wipe.Rolling guide rail and the sliding rail, high sensitivity, small friction coefficient, and the dynamic, static friction coefficient is very small, so the motion is uniform, especially in the low speed movement, the stick-slip phenomenon is not easy to occur; high positioning accuracy,repeatability positioning accuracy is up to 0.2 μ m; traction force is small, wear small, portable in movement; good precision, long service life. But the vibration of rolling guide, high requirements on protection, complicated structure, difficult manufacture, high cost.Automatic tool changer:One, the function of automatic tool changerAutomatic tool changing device can help save the auxiliary time of CNC machine tools, and meet in an installation completed procedure, stepprocessing requirements. Two, on the requirement of automatic tool changerNumerical control machine tool for automatic tool changer requirement is: tool change quickly, time is short, high repetitive positioning accuracy, tool storage capacity is sufficient, small occupation space, stable and reliable work. Three, change the knife form 1, rotary cutter replacementIts structure is similar to the ordinary lathe turret saddle, according to the processing of different objects can be designed into square or six angle form, consists of the NC system sends out the instruction to the rotary cutter.2, the replacement of the spindle head tool changeThe spindle head pre-loaded required tools, in order to machining position, the main motor is switched on, drives the cutter to rotate. The advantage of this method is that eliminates the need for automatic clamping, cutting tool, clamping and cutting tool moving and a series of complex operation, reducetool change time, improve The ATC reliability. 3, the use of changing toolThe processing required tools are respectively arranged in the standard tool, adjust the size of the machine after certain way add to the knife, the exchange device from the knife and the spindle take knife switch.感谢您的阅读,祝您生活愉快。

数控技术类外文文献翻译、中英文翻译、外文翻译

数控技术类外文文献翻译、中英文翻译、外文翻译

外文原文:NC Technology1、Research current situation of NC lathe in our timesResearch and development process to such various kinds of new technologies as numerical control lathe , machining center , FMS , CIMS ,etc. of countries all over the world, linked to with the international economic situation closely. The machine tool industry has international economy to mutually promote and develop, enter 21 alert eras of World Affairs, the function that people's knowledge plays is more outstanding, and the machine tool industry is regarded as the foundation of the manufacturing industry of the machine, its key position and strategic meaning are more obvious. Within 1991-1994 years, the economic recession of the world, expensive FMS, CIMS lowers the temperature, among 1995-2000 years, the international economy increases at a low speed, according to requisition for NC lathe and the world four major international lathes exhibition in order to boost productivity of users of various fields of present world market (EMO , IMTS , JIMTOF , China CIMT of Japan of U.S.A. of Europe), have the analysis of the exhibit, there are the following several points mainly in the technical research of NC lathe in our times:(1)、Pay more attention to new technology and innovationWorldwide , are launching the new craft , new material , new structure , new unit , research and development of the new component in a more cost-effective manner, developmental research of for instance new cutter material , the new electric main shaft of main shaft structure , high speed , high-speed straight line electrical machinery ,etc.. Regard innovating in improvement of the processing technology as the foundation, for process ultra and hard difficult to cut material and special composite and complicated part , irregular curved surface ,etc. research and develop new lathe variety constantly.(2)、Improve the precision and research of machine toolingIn order to improve the machining accuracy of the machining center, are improving rigidity of the lathe, reduction vibration constantly, dispel hotly and out of shape, reduce the noise , improve the precision of localization of NC lathe, repeat precision, working dependability , stability , precision keeping, world a lot of country carry on lathe hot error , lathe sport and load out of shape software of error compensate technical research, take precision compensate, software compensate measure improve , some may make this kind of error dispel 60% already. And is developing retrofit constantly, nanometer is being processed.(3)、Improve the research of the machine tooling productivityWorld NC lathe, machining center and corresponding some development of main shaft, electrical machinery of straight line, measuring system, NC system of high speed, under the prerequisite of boosting productivity.(4)、What a lot of countries have already begun to the numerical control system melt intelligently, openly, study networkedlyA、Intelligent research of the numerical control systemMainly showing in the following aspects: It is intelligent in order to pursue the efficiency of processing and process quality, the self-adaptation to the processing course is controlled, the craft parameter produces research automatically; Join the convenient one in order to improve the performance of urging and use intelligently, to the feedback control, adaptive operation , discerning automatically load selects models automatically, since carries on research whole definitely ,etc. of the electrical machinery parameter; There are such research of the respect as intelligent automatic programming , intelligent man-machine interface , intelligence diagnosing , intelligent monitoring ,etc..B、The numerical control system melts and studies openMainly showing in the following aspects: The development of the numerical control system is on unified operation platform, face the lathe producer and support finally, through changing, increasing or cutting out the structure target(numerical control target ), form the seriation, and can use users specially conveniently and the technical know-how is integrated in the control system, realize the open numerical control system of different variety, different grade fast, form leading brand products with distinct distinction. System structure norm of the open numerical control system at present, norm, disposing the norm, operation platform, numerical control systematic function storehouse and numerical control systematic function software developing instrument, etc. are the core of present research to pass through.C、Meeting the manufacture system of the production line , demand for the information integration of the manufacturing company networkedly greatly of numerical control equipment, it is a basic unit of realizing the new manufacture mode too.2、Classification of the machining center(1)Process according to main shaft space position when it classifies to be as follows, horizontal and vertical machining center.Horizontal machining center, refer to the machining center that the axis level of the main shaft is set up. Horizontal machining center for 3-5 sport coordinate axis, acommon one three rectilinear motion coordinate axis and one turn the coordinate axis of sports round (turn the working bench round), it can one is it is it finish other 4 Taxi processing besides installing surfaces and top surfaces to insert to install in work piece, most suitable for processing the case body work piece. Compared with strength type machining center it, the structure is complicated, the floor space is large, quality is large, the price is high.Vertical machining center, the axis of the main shaft of the vertical machining center, in order to set up vertically, its structure is mostly the regular post type, the working bench is suitable for processing parts for the slippery one of cross, have 3 rectilinear motion coordinate axis generally, can find a room for one horizontal numerical control revolving stage (the 4th axle) of axle process the spiral part at working bench. The vertical machining center is of simple structure, the floor space is small, the price is low, after allocating various kinds of enclosures, can carry on the processing of most work pieces.Large-scale gantry machining center, the main shafts are mostly set up vertically, is especially used in the large-scale or with complicated form work piece , is it spend the many coordinate gantry machining center to need like aviation , aerospace industry , some processing of part of large-scale steam turbine.Five machining centers, this kind of machining center has function of the vertical and horizontal machining center, one is it after inserting, can finish all five Taxi processing besides installing the surface to install in work piece, the processing way can make form of work piece error lowest, save 2 times install and insert working, thus improve production efficiency, reduce the process cost.(2)Classify by craft useIs it mill machining center to bore, is it mill for vertical door frame machining center, horizontal door frame mill the machining center and Longmen door frame mill the machining center to divide into. Processing technology its rely mainly on the fact that the door frame is milled, used in case body, shell and various kinds of complicated part special curve and large processes , curved surface of outline process, suitable for many varieties to produce in batches small.Complex machining center, point five times and compound and process mainly, the main shaft head can be turned round automatically, stand, lie and process, after the main shaft is turned round automatically, realize knowing that varies in the horizontal and vertical direction.(3)Classify by special functionSingle working bench, a pair of working bench machining center;Single axle, dual axle, three axle can change machining center, main shaft of case;Transfer vertically to the tower machining center and transfer;One hundred sheets of storehouses adds the main shaft and changes one one hundred sheets of machining centers;One hundred sheets of storehouses connects and writes hands to add the main shaft and change one hundred sheets of machining centers;One hundred sheets of storehouses adds the manipulator and adds one pair of main shafts to transfer to the tower machining center.3、Development trend of the current numerical control latheAt present, the advanced manufacturing technology in the world is rising constantly, such application of technology as ultrafast cutting , ultraprecision processing ,etc., the rapid development of the flexible manufacturing system and integrated system of the computer one is constant and ripe, have put forward higher demand to the process technology of numerical control. Nowadays the numerical control lathe is being developed in several following directions.(1). The speed and precision at a high speed , high accuracy are two important indexes of the numerical control lathe, it concerns directly that processes efficiency and product quality. At present, numerical control system adopt-figure number, frequency high processor, in order to raise basic operation speed of system. Meanwhile, adopt the super large-scale integrated circuit and many microprocessors structure, in order to improve systematic data processing ability, namely improve and insert the speed and precision of mending operation. Adopt the straight line motor and urge the straight line of the lathe working bench to be servo to enter to the way directly, it is quite superior that its responds the characteristic at a high speed and dynamically. Adopt feedforward control technology, make it lag behind error reduce greatly, thus improve the machining accuracy cut in corner not to track.For meet ultrafast demand that process, numerical control lathe adopt main shaft motor and lathe structure form that main shaft unite two into one, realize frequency conversion motor and lathe main shaft integrate , bearing , main shaft of electrical machinery adopt magnetism float the bearing , liquid sound pigeonhole such forms as the bearing or the ceramic rolling bearing ,etc.. At present, ceramic cutter and diamond coating cutter have already begun to get application.(2). Multi-functional to is it change all kinds of machining centers of organization (a of capacity of storehouse can up to 100 of the above ) automatically tofurnished with, can realize milling paring , boring and pares , bores such many kinds of processes as paring , turning , reaming , reaming , attacking whorl ,etc. to process at the same time on the same lathe , modern numerical control lathe adopt many main shaft , polyhedron cut also , carry on different cutting of way process to one different position of part at the same time. The numerical control system has because adopted many CPU structure and cuts off the control method in grades, can work out part processing and procedure at the same time on a lathe, realize so-called "the front desk processes, the backstage supporter is an editor ". In order to meet the needs of integrating the systematic one in flexible manufacturing system and computer, numerical control system have remote serial interface , can network , realize data communication , numerical control of lathe, can control many numerical control lathes directly too.(3). Intelligent modern numerical control lathe introduce the adaptive control technology, according to cutting the change of the condition, automatic working parameter, make the processing course can keep the best working state , thus get the higher machining accuracy and roughness of smaller surface , can improve the service life of the cutter and production efficiency of the equipment at the same time . Diagnose by oneself, repair the function by oneself, among the whole working state, the system is diagnosed, checked by oneself to CNC system and various kinds of equipment linking to each other with it at any time. While breaking down, adopt the measure of shutting down etc. immediately, carry on the fault alarm, brief on position, reason to break down, etc.. Can also make trouble module person who take off automatically, put through reserve module ,so as to ensure nobody demand of working environment. For realize high trouble diagnose that requires, its development trend adopts the artificial intelligence expert to diagnose the system.(4).Numerical control programming automation with the development of application technology of the computer, CAD/CAM figure interactive automatic programming has already get more application at present, it is a new trend of the technical development of numerical control. It utilize part that CAD draw process pattern , is it calculate the trailing punishing to go on by cutter orbit data of computer and then, thus produce NC part and process the procedure automatically, in order to realize the integration of CAD and CAM. With the development of CIMS technology , the full-automatic programming way in which CAD/CAPP/CAM integrates has appeared again at present, it, and CAD/CAM systematic programming great differencetheir programming necessary processing technology parameter needn't by artificial to participate in most, get from CAPP database in system directly.(5). The dependability of the dependability maximization numerical control lathe has been the major indicator that users cared about most all the time. The numerical control system will adopt the circuit chip of higher integrated level, will utilize the extensive or super large-scale special-purpose and composite integrated circuit, in order to reduce the quantity of the components and parts, to improve dependability. Through the function software of the hardware, in order to meet various kinds of demands for controlling the function, adopt the module, standardization, universalization and seriation of the structure lathe noumenon of the hardware at the same time, make not only improve the production lot of the hardware but also easy to is it produce to organize and quality check on. Still through operating and starting many kinds of diagnostic programs of diagnosing, diagnosing, diagnosing off-line online etc. automatically, realize that diagnoses and reports to the police the trouble to hardware, software and various kinds of outside equipment in the system. Utilize the warning suggestion, fix a breakdown in time; Utilize fault-tolerant technology, adopt and design the important part " redundantly ", in order to realize the trouble resumes by oneself; Utilize various kinds of test, control technology, excess of stroke, knife damages, interfering, cutting out, etc. at the time of various kinds of accidents as production, carry on corresponding protection automatically.(6). Control system miniaturization systematic miniaturization of numerical control benefit and combine the machine, electric device for an organic whole. Adopt the super large-scale integrated component , multi-layer printed circuit board mainly at present, adopt the three-dimensional installation method , make the electronic devices and components must use the high density to install, narrow systematic occupying the space on a larger scale. And utilize the new-type slim display of colored liquid crystal to substitute the traditional cathode ray tube, will make the operating system of numerical control miniaturize further. So can install it on the machine tool conveniently, benefit the operation of the numerical control lathe correctly even more.本文出自:Shigley J E. Mechanical Engineering Design. New York: McGraw-Hill, 1998译文:数控技术1、当前世界NC机床的研究现状世界各国对数控机床、加工中心以至FMS、CIMS等各种新技术的研究与发展进程,是与世界经济形势紧密相连的。

(数控加工)机械类数控外文翻译外文文献英文文献数控精编

(数控加工)机械类数控外文翻译外文文献英文文献数控精编

(数控加工)机械类数控外文翻译外文文献英文文献数控NumericalControlOneofthemostfundamentalconceptsintheareaofadvancedmanufactur ingtechnologiesisnumericalcontrol(NC).PriortotheadventofNC,allmachine toolsweremanualoperatedandcontrolled.Amongthemanylimitationsassoc iatedwithmanualcontrolmachinetools,perhapsnoneismoreprominentthan thelimitationofoperatorskills.Withmanualcontrol,thequalityoftheproducti sdirectlyrelatedtoandlimitedtotheskillsoftheoperator.Numericalcontrolrep resentsthefirstmajorstepawayfromhumancontrolofmachinetools.Numericalcontrolmeansthecontrolofmachinetoolsandothermanufact uringsystemsthoughtheuseofprerecorded,writtensymbolicinstructions.Ra therthanoperatingamachinetool,anNCtechnicianwritesaprogramthatissue soperationalinstructionstothemachinetool,Foramachinetooltobenumeric allycontrolled,itmustbeinterfacedwithadeviceforacceptinganddecodingth ep2ogrammedinstructions,knownasareader.Numericalcontrolwasdevelopedtoovercomethelimitationofhumanop erator,andithasdoneso.Numericalcontrolmachinesaremoreaccuratethanm anuallyoperatedmachines,theycanproducepartsmoreuniformly,theyarefas ter,andthelong-runtoolingcostsarelower.ThedevelopmentofNCledtothede velopmentofseveralotherinnovationsinmanufacturingtechnology:1.Electricaldischargemachining.sercutting.3.Electronbeamwelding.Numericalcontrolhasalsomademachinetoolsmoreversatilethantheirmanuallyoperatedpredecessors.AnNCmachinetoolcanautomaticallyproduc eawidevarietyofpar4s,eachinvolvinganassortmentofundertaketheproducti onofproductsthatwouldnothavebeenfeasiblefromaneconomicperspective usingmanuallycontrolledmachinetoolsandprocesses.Likesomanyadvancedtechnologies,NCwasborninthelaboratoriesofthe MassachusettsInstituteofTechnology.TheconceptofNCwasdevelopedinthe early1950swithfundingprovidedbytheU.SAirForce.Initsearlieststages,NCm achineswereabletomakestraightcutsefficientlyandeffectively.However,curvedpathswereaproblembecausethemachinetoolhadtobe programmedtoundertakeaseriesofhorizontalandverticalstepstoproducea curve.Theshorteristhestraightlinesmakingupthestep,thesmootheris4hecu rve.Eachlinesegmentinthestepshadtobecalculated.Thisproblemledtothedevelopmentin1959oftheAutomaticallyProgram medTools(APT)languageforNCthatusesstatementssimilartoEnglishlangua getodefinethepartgeometry,describethecuttingtoolconfiguration,andspe cifythenecessarymotions.ThedevelopmentoftheAPTlanguagewasamajors tepforwardinthefurtherdevelopmentofNCtechnology.TheoriginalNCsyste mwerevastlydifferentfromthoseusedpunchedpaper,whichwaslatertorepla cedbymagneticplastictape.Atapereaderwasusedtointerprettheinstruction swrittenonthetapeforthemachine.Together,all/fthisrepresentedgiantstepf orwardinthecontrolofmachinetools.However,therewereanumberofproble mswithNCatthispointinitsdevelopment.Amajorproblemwasthefragilityofthepunchedpapertapemedium.Itwas commonforthepapercontainingtheprogrammedinstructionstobreakortea rduringamachiningprocess,Thisproblemwasexacerbatedbythefactthateac hsuccessivetimeapartwasproducedonamachinetool,thepapertapecarryin gtheprogrammedinstructionshadtorerunthoughtthereader.Ifitwasnecessa rytoproduce100copiesofagivenpart,itwasalsonecessarytorunthepapertap ethoughtthereader100separatetimes.Fragilepapertapessimplycouldnotwi thstandtherigorsofshopfloorenvironmentandthiskindofrepeateduse.Thisledtothedevelopmentofaspecialmagnetictape.Whereasthepapert apecarriedtheprogrammedinstructionsasaseriesofholespunchedinthetap e,theThismostimportantofthesewasthatitwasdifficultorimpossibletochang etheinstructionsenteredonthetape.Tomakeeventhemostminoradjustment sinaprogramofinstructions,itwasnecessarytointerruptmachiningoperation sandmakeanewtape.Itwasalsostillnecessarytorunthetapethoughtthereade rasmanytimesastherewerepartstobeproduced.Fortunately,computertechn ologybecomearealityandsoonsolvedtheproblemsofNC,associatedwithpun chedpaperandplastictape.Thedevelopmentofaconceptknownasnumericalcontrol(DNC)solvethe paperandplastictapeproblemsassociatedwithnumericalcontrolbysimplyeli minatingtapeasthemediumforcarryingtheprogrammedinstructions.Indire ctnumericalcontrol,machinetoolsaretied,viaadatatransmissionlink,toahost computerandfedtothemachinetoolasneededviathedatatransmissionlinkage.Directnumericalcontrolrepresentedamajorstepforwardoverpunchedta peandplastictape.However,itissubjecttothesamelimitationasalltechnologi esthatdependonahostcomputer.Whenthehostcomputergoesdown,thema chinetoolsalsoexperiencedowntime.Thisproblemledtothedevelopmentofc omputernumericalcontrol.Thedevelopmentofthemicroprocessorallowedforthedevelopmentofpr ogrammablelogiccontrollers(PLC)andmicrocomputers.Thesetwotechnolo giesallowedforthedevelopmentofcomputernumericalcontrol(CNC).WithC NC,eachmachinetoolhasaPLCoramicrocomputerthatservesthesamepurpo se.Thisallowsprogramstobeinputandstoredateachindividualmachinetool. CNCsolvedtheproblemsassociateddowntimeofthehostcomputer,butitintr oducedanotherproblemknownasdatamanagement.Thesameprogrammig htbeloadedontendifferentmicrocomputerswithnocommunicationamongt hem.Thisproblemisintheprocessofbeingsolvedbylocalareanetworksthatco nnectDigitalSignalProcessorsTherearenumeroussituationswhereanalogsignalstobeprocessedinma nyways,likefilteringandspectralanalysis,Designinganaloghardwaretoperfo rmthesefunctionsispossiblebuthasbecomelessandpractical,duetoincrease dperformancerequirements,flexibilityneeds,andtheneedtocutdownondev elopment/testingtime.Itisinotherwordsdifficultpmdesignanaloghardware analysisofsignals.Theactofsamplingansignalintothehatarespecialisedforembeddedsignalprocessingoperations,andsuchaprocessoriscalledaDSP,whichstandsforDi gitalSignalProcessor.TodaytherearehundredsofDSPfamiliesfromasmanym anufacturers,eachonedesignedforaparticularprice/performance/usagegro up.Manyofthelargestmanufacturers,likeTexasInstrumentsandMotorola,off erbothspecialisedDSP’sforcertainfieldslikemotor-controlormodems,and generalhigh-performanceDSP’sthatcanperformbroadrangesofprocessin gtasks.Developmentkitsan`softwarearealsoavailable,andtherearecompani esmakingsoftwaredevelopmenttoolsforDSP’sthatallowstheprogrammer toimplementcomplexprocessingalgorithmsusingsimple“drag‘n’drop ”methodologies.DSP’smoreorlessfallintotwocategoriesdependingontheunderlyingar chitecture-fixed-pointandfloating-point.Thefixed-pointdevicesgenerallyo perateon16-bitwords,whilethefloating-pointdevicesoperateon32-40bitsfl oating-pointwords.Needlesstosay,thefixed-pointdevicesaregenerallychea per.Anotherimportantarchitecturaldifferenceisthatfixed-pointprocessorst endtohaveanaccumulatorarchitec ture,withonlyone“generalpurpose”re gister,makingthemquitetrickytoprogramandmoreimportantly,makingC-c ompilersinherentlyinefficient.Floating-pointDSP’sbehavemorelikecomm ongeneral-purposeCPU’s,withregister-files.TherearethousandsofdifferentDSP’sonthemarket,an ditisdifficulttask findingthemostsuitableDSPforaproject.Thebestwayisprobablytosetupaco nstraintandwishlist,andtrytocomparetheprocessorsfromthebiggestmanufacturersagainstit.The“bigfour”manufacturersofDSPs:TexasInstruments,Motorola,AT &TandAnalogDevices.Digital-to-analogconversionInthecaseofMPEG-Audiodecoding,digitalcompresseddataisfedintoth eDSPwhichperformsthedecoding,thenthedecodedsampleshavetobeconv ertedbackintotheanalogdomain,andtheresultingsignalfedanamplifierorsi milaraudioequipment.Thisdigitaltoanalogconversion(DCA)isperformedby acircuitwiththesamename&DifferentDCA’sprovidedifferentperformance andquality,asmeasuredbyTHD(Totalharmonicdistortion),numberofbits,lin earity,speed,filtercharacteristicsandotherthings.TheTMS320familyDQPofTexasInstrumentsTheTLS320familyconsistsoffixed-point,floating-point,multiprocessor digitalsignalprocessors(D[Ps),andfoxed-pointDSPcontrollers.TMS320DSP haveanarchitecturedesignedspecificallyforreal-timesignalprocessing.The ’F/C240isanumberofthe’C2000DSPplatform,andisoptimizedforcontro la pplications.The’C24xseriesofDSPcontrollerscombinesthisreal-timeproce ssingcapabilitywithcontrollerperipheralstocreateanidealsolutionforcontro lsystemapplications.ThefollowingcharacteristicsmaketheTMS320familyth erightchoiceforawiderangeofprocessingapplications:---Veryflexibleinstructionset---Inherentoperationalflexibility---High-speedperformance---Innovativeparallelarchitecture---CosteffectivenessDeviceswithinagenerationoftheTMS320familyhavethesameCPUstruc turebutdifferenton-chipmemoryandperipheralconfigurations.Spin-offdev icesusenewcombinationsofOn-chipmemoryandperipheralstosatisfyawide rangeofneedsintheworldwideelectronicsmarket.Byintegratingmemoryand peripheralsontoasinglechip,TMS320devicesreducesystemcostsandsavecir cuitboardspace.The16-bit,fixed-point DSPcoreofthe‘C24xdevicesprovidesanalogde signersadigitalsolutionthatdoesnotsacrificetheprecisionandperformance oftheirsystemperformancecanbeenhancedthroughtheuseofadvancedcont rolalgorithmsfortechniquessuchasadaptivecontrol,Kalmanfiltering,andsta tecontrol.The‘C24xDSPcontrollerofferreliabilityandprogrammability.Anal ogcontrolsystems,ontheotherhand,arehardwiredsolutionsandcanexperien ceperformancedegradationduetoaging,componenttolerance,anddrift.Thehigh-speedcentralprocessingunit(CPU)allowsthedigitaldesignert oprocessalgorithmsinrealtimeratherthanapproximateresultswithlook-upt ables.TheinstructionsetoftheseDSPcontrollers,whichincorporatesbothsign alprocessinginstructionsandgeneral-purposecontrolfunctions,coupledwit htheextensivedevelopmenttimeandprovidesthesameeaseofuseastradition al8-and16-bitmicrocontrollers.Theinstructionsetalsoallowsyoutoretainyoursoftwareinvestmentwhenmovingfromothergeneral-purpose‘C2xxgen eration,sourcecodecompatiblewiththe’C2xgeneration,andupwardlysour cecodecompatiblewiththe‘C5xgenerationofDSPsfro mTexasInstruments.The‘C24xarchitectureisalsowell-suitedforprocessingcontrolsignals.I tusesa16-bitwordlengthalongwith32-bitregistersforstoringintermediatere sults,andhastwohardwareshiftersavailabletoscalenumbersindependentlyo ftheCPU.Thiscombinationminimizesquantizationandtruncationerrors,andi ncreasesp2ocessingpowerforadditionalfunctions.Suchfunctionsmightincl udeanotchfilterthatcouldcancelmechanicalresonancesinasystemoranesti mationtechniquethatcouldeliminatestatesensorsinasystem.The‘C24xDSPcontrollerstakeadva ntageofansetofperipheralfunction sthatallowTexasInstrumentstoquicklyconfigurevariousseriesmembersfordi fferentprice/performancepointsorforapplicationoptimization.Thislibraryofbothdigitalandmixed-signalperipheralsincludes:---Timers---Serialcommunicationsports(SCI,SPI)---Analog-to-digitalconverters(ADC)---Eventmanager---Systemprotection,suchaslow-voltageandwatchdogtimerTheDSPcontrollerperipherallibraryiscontinuallygrowingandchanging tosuittheoftomorrow’sembeddedcontrolmarketplace.TheTMS320F/C240isthefirs tstandarddeviceintroducedinthe‘24xseriesofDSPcontrollers.Itsetsthestandardforasingle-chipdigitalmotorcontrolle r.The‘240canexecute20MIPS.Almostallinstructionsareexecutedinasimple cycleof50ns.Thishighperformanceallowsreal-timeexecutionofverycomple 8controlalgorithms,suchasadaptivecontrolandKalmanfilters.Veryhighsam plingratescanalsobeusedtominimizeloopdelays.The‘240hasthearchitecturalfeaturesnecessaryforhigh-speedsignalp rocessinganddigitalcontrolfunctions,andithastheperipheralsneededtopro videasingle-chipsolutio nformotorcontrolapplications.The‘240ismanufac turedusingsubmicronCMOStechnology,achievingalogpowerdissipationrat ing.Alsoincludedareseveralpower-downmodesforfurtherpowersavings.So meapplicationsthatbenefitfromtheadvancedprocessingpowerofthe‘240i nclude:---Industrialmotordrives---Powerinvertersandcontrollers---Automotivesystems,suchaselectronicpowersteering,antilockbrake s,andclimatecontrol---ApplianceandHVACblower/compressormotorcontrols---Printers,copiers,andotherofficeproducts---Tapedrives,magneticopticaldrives,andothermassstorageproducts ---RoboticandCNCmillingmachinesTofunctionasasystemmanager,aDSPmusthaverobuston-chipI/Oando therperipherals.Theeventmanagerofthe‘240isunlikeanyotheravailableonaDSP.Thisapplication-optimizedperipheralunit,coupledwiththehighperfor manceDSPcore,enablestheuseofadvancedcontroltechniquesforhigh-preci sionandhigh-efficiencyfullvariable-speedcontrolofallmotortypes.Includei ntheeventmanagerarespecialpulse-widthmodulation(PWM)generationfu nctions,suchasaprogrammabledead-bandfunctionandaspacevectorPWMs tatemachinefor3-phasemotorsthatprovidesstate-of-the-artmaximumeffic iencyintheswitchingofpowertransistors.Thereindependentupdowntimers,eachwithit’sowncompareregister, supportthegenerationofasymmetric(noncentered)aswellassymmetric(cen tered)PWMwaveforms.Open-LoopandClosed-LoopControlOpen-loopControlSystemsThewordautomaticimpliesthatthereisacertainamountofsophisticatio ninthecontrolsystem.Byautomatic,itgenerallymeansThatthesystemisusuall ycapableofadaptingtoavarietyofoperatingconditionsandisabletorespondt oaclassofinputssatisfactorily.However,notanytypeofcontrolsystemhasthea ually,theautomaticfeatureisachievedbyfeed.gthefeedbackstructure,itiscalledanopen-loopsystem,whichisthesimp lestandmosteconomicaltypeofcontrolsystem.inaccuracyliesinthefactthato nemaynotknowtheexactcharacteristicsofthefurther,whichhasadefinitebea ringontheindoortemperature.Thisalcopointstoanimportantdisadvantageo ftheperformanceofanopen-loopcontrolsystem,inthatthesystemisnotcapableofadaptingtovariationsinenvironmentalconitionsortoexternaldisturban ces.Inthecaseofthefurnacecontrol,perhapsanexperiencedpersoncanprovi decontrolforacertaindesiredtemperatureinthehouse;butidthedoorsorwin dowsareopenedorclosedintermittentlyduringtheoperatingperiod,thefinal temperatureinsidethehousewillnotbeaccuratelyregulatedbytheopen-loop control.Anelectricwashingmachineisanothertypicalexampleofanopen-loops ystem,becausetheamountofwashtimeisentirelydeterminedbythejudgmen tandestimationofthehumanoperator.Atrueautomaticelectricwashingmach ineshouldhavethemeansofcheckingthecleanlinessoftheclothescontinuous lyandturnitsedtoffwhenthedesireddegisedofcleanlinessisreached.Closed-LoopControlSystemsWhatismissingintheopen-loopcontrolsystemformoreaccurateandmo readaptablecontrolisalinkorfeedbackfromtheoutputtotheinputofthesyste m.Inordertoobtainmoreaccuratebontrol,thecontrolledsignalc(t)mustbefe dbackandcomparedwiththereferenceinput,andanactuatingsignalproporti onaltothedifferenceoftheoutputandtheinputmustbesentthroughthesyste mtocorrecttheerror.Asystemwithoneormorefeedbackpat(slikethatjustdesc ribediscalledaclosed-loopsystem.humanbeingareprobablythemostcompl exandsophisticatedfeedbackcontrolsysteminexistence.Ahumanbeingmay beconsideredtobeacontrolsystemwithmanyinputsandoutputs,capableofc arryingouthighlycomplexoperations.Toillustratethehumanbeingasafeedbackcontrolsystem,letusconsidert hattheobjectiveistoreachforanobjectonaperformthetask.Theeyesserveasa sensingdevicewhichfeedsbackcontinuouslythepositionofthehand.Thedist ancebetweenthehandandtheobjectistheerror,whichiseventuallybroughtto zeroasthehandreachertheobject.Thisisatypicalexampleofclosed-loopcontr ol.However,ifoneistoldtoreachfortheobjectandthenisblindolded,onecano nlyreachtowardtheobjectbyestimatingitsexactposition.ItisAsantherillustra tiveexampleofaclosed-loopcontrolsystem,showstheblockdiagramoftheru ddercontrolsystemofThebasicalementsandtheblocadiagramofaclosed-loo pcontrolsystemareshowninfig.Ingeneral,theconfigurationofafeedbackcon trolsystemmaynotbeconstrainedtothatoffig&.Incomplexsystemstheremay bemultitudeoffeedbackloopsandelementblocks.数控在先进制造技术领域最根本的观念之壹是数控(NC)。

机床数控化改造外文文献翻译、中英文翻译

机床数控化改造外文文献翻译、中英文翻译

外文资料First, CNC of the need for transformation1.1, microscopic view of the necessity ofFrom the micro perspective, CNC machine tools than traditional machines have the following prominent superiority, and these advantages are from the NC system includes computer power.1.1.1 can be processed by conventional machining is not the curve, surface and other complex partsBecause computers are superb computing power can be accurately calculated instantaneous each coordinate axis movement exercise should be instantaneous, it can compound into complex curves and surfaces.1.1.2 automated processing can be achieved, but also flexible automation to increase machine efficiency than traditional 3 to 7 times.Because computers are memory and storage capacity, can be imported and stored procedures remember down, and then click procedural requirements to implement the order automatically to achieve automation. CNC machine tool as a replacement procedures, we can achieve another work piece machining automation, so that single pieces and small batch production can be automated, it has been called "flexible automation."1.1.3 high precision machining parts, the size dispersion of small, easy to assemble, no longer needed "repair."1.1.4 processes can be realized more focused, in part to reduce the frequent removal machine.1.1.5 have automatic alarm, automatic control, automatic compensation, and other self-regulatory functions, thus achieving long unattended processing.1.1.6 derived from the benefits of more than five.Such as: reducing the labor intensity of the workers, save the labor force (onecan look after more than one machine), a decrease of tooling, shorten Trial Production of a new product cycle and the production cycle, the market demand for quick response, and so on.These advantages are our predecessors did not expect, is a very major breakthrough. In addition, CNC machine tools or the FMC (Flexible Manufacturing Cell), FMS (flexible manufacturing system) and CIMS (Computer Integrated Manufacturing System), and other enterprises, the basis of information transformation. NC manufacturing automation technology has become the core technology and basic technology.1.2, the macro view of the necessityFrom a macro perspective, the military industrial developed countries, the machinery industry, in the late 1970s, early 1980s, has begun a large-scale application of CNC machine tools. Its essence is the use of information technology on the traditional industries (including the military, the Machinery Industry) for technological transformation. In addition to the manufacturing process used in CNC machine tools, FMC, FMS, but also included in the product development in the implementation of CAD, CAE, CAM, virtual manufacturing and production management in the implementation of the MIS (Management Information System), CIMS, and so on. And the products that they produce an increase in information technology, including artificial intelligence and other content. As the use of information technology to foreign forces, the depth of Machinery Industry (referred to as information technology), and ultimately makes their products in the international military and civilian products on the market competitiveness of much stronger. And we in the information technology to transform traditional industries than about 20 years behind developed countries. Such as possession of machine tools in China, the proportion of CNC machine tools (CNC rate) in 1995 to only 1.9 percent, while Japan in 1994 reached 20.8 percent, every year a large number of imports of mechanical and electrical products. This also explains the macro CNC transformation of the need.Second, CNC machine tools and production lines of the transformation of the market2.1, CNC transformation of the marketMy current machine total more than 380 million units, of which only the total number of CNC machine tool 113,400 Taiwan, or that China's CNC rate of less than 3 percent. Over the past 10 years, China's annual output of about 0.6 CNC machine tools to 0.8 million units, an annual output value of about 1.8 billion yuan. CNC machine tools annual rate of 6 per cent. China's machine tool easements over age 10 account for more than 60% below the 10 machines, automatic / semi-automatic machine less than 20 per cent, FMC / FMS, such as a handful more automated production line (the United States and Japan automatic and semi-automatic machine, 60 percent above). This shows that we the majority of manufacturing industries and enterprises of the production, processing equipment is the great majority of traditional machine tools, and more than half of military age is over 10 years old machine. Processing equipment used by the prevalence of poor quality products, less variety, low-grade, high cost, supply a long period, in view of the international and domestic markets, lack of competitiveness, and a direct impact on a company's products, markets, efficiency and impact The survival and development of enterprises. Therefore, we must vigorously raise the rate of CNC machine tools.2.2, import equipment and production lines of the transformation of NC marketSince China's reform and opening up, many foreign enterprises from the introduction of technology, equipment and production lines for technological transformation. According to incomplete statistics, from 1979 to 1988 10, the introduction of technological transformation projects are 18,446, about 16.58 billion US dollars.These projects, the majority of projects in China's economic construction play a due role. Some, however, the introduction of projects due to various reasons, not equipment or normal operation of the production line, and even paralyzed, and the effectiveness of enterprises affected by serious enterprise is in trouble. Some of the equipment, production lines introduced from abroad, the digestion and absorption of some bad, spare parts incomplete, improper maintenance, poor operating results; onlypay attention to the introduction of some imported the equipment, apparatus, production lines, ignore software, technology, and management, resulting in items integrity, and potential equipment can not play, but some can not even start running, did not play due role, but some production lines to sell the products very well, but not because of equipment failure production standards; because some high energy consumption, low pass rate products incur losses, but some have introduced a longer time, and the need for technological upgrading. Some of the causes of the equipment did not create wealth, but consumption of wealth.These can not use the equipment, production lines is a burden, but also a number of significant assets in stock, wealth is repaired. As long as identifying the main technical difficulties, and solve key technical problems, we can minimize the investment and make the most of their assets in stock, gain the greatest economic and social benefits. This is a great transformation of the market.Third, NC transformation of the content and gifted missing3.1, the rise of foreign trade reformIn the United States, Japan and Germany and other developed countries, and their machine transform ation as new economic growth sector, the business scene, is in a golden age. The machine, as well as technology continues to progress, is a machine of the "eternal" issue. China's machine tool industry transformation, but also from old industries to enter the CNC technology mainly to the new industries. In the United States, Japan, Germany, with CNC machine tools and technological transformation of production lines vast market, has formed a CNC machine tools and production lines of the new industry. In the United States, transforming machine tool industry as renewable (Remanufacturing) industry. Renewable industry in the famous companies: Borsches engineering company, atoms machine tool company, Devlieg-Bullavd (Bo) services group, US equipment companies. Companies in the United States-run companies in China. In Japan, the machine tool industry transformation as machine modification (Retrofitting) industry. Conversion industry in the famous companies: Okuma engineering group, Kong 3 Machinery Company, Chiyoda Engineering Company, Nozaki engineering company, Hamada engineeringcompanies, Yamamoto Engineering Company.3.2, the content of NCMachine tools and production line NC transformation main contents of the following:One is the restoration of the original features of the machine tools, production line of the fault diagnosis and recovery; second NC, in the ordinary machine augends significant installations, or additions to NC system, transformed into NC machine tools, CNC machine tools; its Third, renovation, to improve accuracy, efficiency and the degree of automation, mechanical, electrical part of the renovation, re-assembly of mechanical parts processing, restore the original accuracy of their production requirements are not satisfied with the latest CNC system update; Fourth, the technology updates or technical innovation, to enhance performance or grades, or for the use of new technology, new technologies, based on the original technology for large-scale update or technological innovation, and more significantly raise the level, and grades of upgrading.3.3, NC transformation of the gifted missing3.3.1 reduce the amount of investment, shorter delivery timeCompared with the purchase of new machine, the general can save 60% to 80% of the costs and transforming low-cost. Especially for large, special machine tools particularly obvious. General transformation of large-scale machine, spent only the cost of the new machine purchase 1 / 3, short delivery time. But some special circumstances, such as high-speed spindle, automatic tray switching systems and the production of the installation costs too costly and often raise the cost of 2 to 3 times compared with the purchase of new machine, only about 50 percent of savings investment.3.3.2 stable and reliable mechanical properties, structure limitedBy the use of bed, column, and other basic items are heavy and solid casting components, rather than kind of welding components of the machine after the high-performance, quality, and can continue to use the new equipment for many years. But by the mechanical structure of the original restrictions, it is not appropriate to thetransformation of a breakthrough.3.3.3 become familiar with the equipment, ease of operation and maintenanceThe purchase of new equipment, new equipment do not know whether to meet the processing requirements. Transformation is not, can be used to calculate the machine processing capacity; In addition, since the use of many years, the operator of the machine has long been understood that in the operation, use and maintenance of the training time is short, quick. Transformation of the machine tools installed, we can achieve full load operation.3.3.4 can take full advantage of the existing conditionsTake full advantage of the existing foundation, not like buying new equipment as necessary to build a foundation.3.3.5 can be used as control technologyAccording to the development speed of technological innovation and in a timely manner increased level of automation in production equipment and efficiency, improve the quality of equipment and grades, and the old machine will be replaced by the current level of machine.Fourth, the main steps of CNC machine tools4.1, for the determination of transformationThrough analysis of the feasibility of transforming the future, we can against a Taiwan or a few machines determine the current status of reform programmes, which are generally include:4.1.1 mechanical and electrical repair of combiningGenerally speaking, the need for a transformation of the electrical machine, are subject to mechanical repairs. Repairs to determine the requirements, scope, content must be decided by electrical machinery required to transform the structure of the request; transformation to determine electrical and mechanical repair, alteration between the staggered time requirements. The mechanical properties of intact electrical transform the basis of success.4.1.2 easy first, and to the overall situation after the first localThe removal of the original system must control the original drawings, carefully, to make drawings in a timely manner marked to prevent the demolition or omission (of local circumstances). In the process of demolition will discover some new system design in the gaps, and that should be promptly added, removed and parts of the system should be disaggregated, safekeeping, in case of failure or partial failure reinstated. There is a definite value, and can be used for spare parts for other machines. Must not extravagantly used and misplaced.4.2 reasonable arrangements for a new location and routing systemUnder the new system design drawings and reasonable new system configurations, including fixed box, panel installation, alignments, and the fixed position adjustment components, sealing and necessary, such as decoration. Connection must be a clear division of work, it was reviewed inspection to ensure connectivity of norms, diameter appropriate, accurate, reliable handsome.4.3 DebuggingCommissioning must be identified in advance by the steps and requirements. Debugging should be cool-headed, keep records, in order to identify a nd solve problems. Commissioning of the first test sensitivity security protection systems to prevent physical, equipment accidents. Debugging the scene must be cleaned, no superfluous items; coordinates extension units in the campaign centre of the whole trip; empty can test, first empty after loading; can simulate the test, after the first real dynamic simulation; can manually the upper hand After moving automatically.4.4, acceptance and post-workAcceptance of the work to employ the staff to join, has been developed in accordance with the acceptance criteria. The transformation of the late work is also very important, it is conducive to enhancing the level of technical projects and equipment as soon as possible so that production. Acceptance and post include:4.4.1 machine mechanical properties acceptanceAfter mechanical repairs and maintenance as well as a full transformation, the mechanical properties of the machine tools should meet the requirement, in the geometric accuracy should be within the limits prescribed.4.4.2 electrical control function and control accuracy acceptanceElectrical control the various functions of action must be normal, sensitive and reliable. Application control accuracy of the system itself functions (such as stepping dimensions, etc.) and standard measurement apparatus (such as laser interferometer, coordinate measurement machines) inspection, the scope of accuracy achieved. At the same time also and the transformation of the former machine tool accuracy of the various functions and to contrast, poor access to quantifiable indicators.4.4.3 specimen cutting AcceptanceYou can refer to the CNC machine tool cutting at home and abroad specimen standards, qualified operatives, with the programming staff to test cutting. Acceptance specimen cutting machine stiffness can be cutting, noise, trajectory, and other related actions, the general should not be used for product components specimen use.4.4.4 drawings, information acceptanceMachine transformation of the latter should be timely drawings (including schematics, layout plans, wiring diagram, ladder diagram, etc.), information (including various brochures), the transformation of files (including the transformation before and after the various records) summary, collating, transfer to stall. Maintain data integrity, effective, continuous, and that the future stability of the equipment running is very important.4.4.5 summing up, enhancingAfter the end of each should be promptly summed up, helps improve the operational level of technical personnel, but also conducive to the whole enterprise technical progress.中文译文一、机床数控化改造的必要性1.1、微观看改造的必要性从微观上看,数控机床比传统机床有以下突出的优越性,而且这些优越性均来自数控系统所包含的计算机的威力。

数控系统外文翻译外文文献英文文献

数控系统外文翻译外文文献英文文献

Numerical Control SystemThe numerical control system is the digital control system abbreviation. By early is composed of hardware circuit is called hardware numerical control (Hard NC), after 1970, hardware circuit components gradually instead by the computer called for computer numerical control system.Computerized numerical control system is a system that is use computer control processing function to achieve numerical control system. CNC system according to the computer memory stored in the control program execution part or all, numerical control function, and is equipped with interface circuit and servo drive the special computer system.CNC system consists of NC program, input devices; output devices, computer numerical control equipment (CNC equipment), programmable logic controllers (PLC), the spindle and feed drive (servo) drive (including detection devices) and so on.The core of CNC system is equipment. By using the computer system with the function of software and PLC instead of the traditional machine electric device to make the system logic control more compact, its flexibility and versatility, reliability become more better, easy to implement complex numerical control function, use and maintenance can be more convenient, and it also has connected and super ordination machine and the remote communication function.At present, the numerical control system has variety of different forms; composition structure has its own characteristics. These structural features from thebasic requirements of the initial system design and engineering design ideas. For example, the control system of point and continuous path control systems have different requirements. For the T system and the M system, there are also very different, the former applies to rotary part processing, the latter suitable for special-shaped the axially symmetrical parts processing. For different manufacturers, based on historical development factors and vary their complex factors, may also be thinking in the design is different. For example, the United States Dynapath system uses a small plate for easy replacement and flexible combination of the board; while Japan FANUC system is a large plate structure tends to make the system work in favor of reliability, make the system MTBF rate continues to increase. However, no matter what kind of system, their basic principle and structure are very similar.The numerical control system generally consists of three major components, namely the control system, servo system and position measuring system. Control procedures by interpolation operation work piece, issue control instructions to the servo drive system; servo drive system control instructions amplified by the servo motor-driven mechanical movement required; measurement system detects the movement of mechanical position or speed, and feedback to the control system, to modify the control instructions. These three parts combine to form a complete closed-loop control of the CNC system.Control system mainly consists of bus, CPU, power supply, memory, operating panel and display, position control unit, programmable logic controller control unit and data input / output interface and so on. The latest generation of CNC system alsoincludes a communication unit; it can complete the CNC, PLC's internal data communications and external high-order networks. Servo drive system including servo drives and motors. Position measuring system is mainly used grating, or circular grating incremental displacement encoder.CNC system hardware from the NC device, input / output devices, drives and machine logic control devices, electrical components, between the four parts through the I / O interface to interconnect.Numerical control device is the core of CNC system, its software and hardware to control the implementation of various CNC functions.The hardware structure of no device by CNC installations in the printed circuit board with infixing pattern can be divided into the big board structure and function module (small board) structure; Press CNC apparatus hardware manufacturing mode, can be divided into special structure and personal computer type structure; Press CNC apparatus in the number of microprocessor can be divided into single microprocessor structure and many microprocessor structure.(1)Large panel structure and function templates structure1) Large panel structurePanel structures CNC system CNC equipment from the main circuit board, position control panels, PC boards, graphics control panel, additional I / O board and power supply unit and other components. The main circuit board printed circuit board is big; the other circuit board is a small plate, inserted in the large printed circuit board slot. This structure is similar to the structure of micro-computer.2) Function templates structure(2)Single-microprocessor structure and mulct-microprocessor structure1) Single-microprocessor structureIn a single-microprocessor structure, only a microprocessor to focus on control, time-sharing deals with the various tasks of CNC equipment.2) melt-microprocessor structureWith the increase in numerical control system functions, CNC machine tools to improve the processing speed of a single microprocessor CNC system can not meet the requirement; therefore, many CNC systems uses a multi-microprocessor structure. If a numerical control system has two or more microprocessors, each microprocessor via the data bus or communication to connect, share system memory and common I / O interfaces, each processor sharing system Part of the work, which is multi-processor systems.CNC software is divided into application software and system software. CNC system software for the realization of various functions of the CNC system, the preparation of special software, also known as control software, stored in the computer EPROM memory. CNC Systems feature a variety of settings and different control schemes, and their system software in the structure and size vary widely, but generally include input data processing procedures, computing interpolation procedures, speed control procedures, management procedures and diagnostic procedures.(1)Input data processing proceduresIt receives input part program, the standard code, said processing instructions anddata decoding, data processing, according to the prescribed format for storage. Some systems also calculated to compensate, or interpolation operation and speed control for pre-computation. Typically, the input data processing program, including input, decoding and data processing three elements.(2)Computing interpolation proceduresCNC work piece processing system according to the data provided, such as curve type, start, end, etc. operations. According to the results of operations were sent to each axis feed pulse. This process is called interpolation operation. Feed drive servo system Impulsive table or by a corresponding movement of the tool to complete the procedural requirements of the processing tasks.Interpolation for CNC system is the side of the operation, while processing, is a typical real-time control, so the interpolation directly affects the speed of operation the machine feed rate, and should therefore be possible to shorten computation time, which is the preparation of interpolation Complements the key to the program.(3)Speed control proceduresSpeed control program according to the given value control the speed of operation of the frequency interpolation, in order to maintain a predetermined feed rate. Changes in speed is large, the need for automatic control of acceleration and deceleration to avoid speed drive system caused by mutations in step.(4)Management proceduresManagement procedures responsible for data input, data processing, interpolation processing services operations as the various procedures for regulation and management.Management process but also on the panel command, the clock signal, the interrupt caused by fault signals for processing.(5)Diagnostic proceduresDiagnostic features are found in the running system failure in a timely manner, and that the type of failure. You can also run before or after the failure, check the system main components (CPU, memory, interfaces, switches, servo systems, etc.) function is normal, and that the site of failure.MachiningAny machining must have three basic conditions: machining tools, work piece and machining sports. Machining tool edge should be, the material must be rigid than the work piece. Different forms of tool structure and cutting movements constitute different cutting methods. Blade with a blade-shaped and have a fixed number of methods for cutting tools for turning, drilling, boring, milling, planning, broaching, and sawing, etc.; edge shape and edge with no fixed number of abrasive or abrasive Cutting methods are grinding, grinding, honing and polishing.Machining is the most important machinery manufacturing processing methods. Although the rough improve manufacturing precision, casting, forging, extrusion, powder metallurgy processing applications on widely, but to adapt to a wide range of machining, and can achieve high accuracy and low surface roughness, in Manufacturing still plays an important role in the process. Cutting metal materials have many classifications. Common are the following three kinds.By cutting process feature distinguishing characteristics of the decision process on the structure of cutting tools and cutting tools and work piece relative motion form. According to the technical characteristics of cutting can be divided into: turning, milling, drilling, boring, reaming, planning, shaping, slotting, broaching, sawing, grinding, grinding, honing, super finishing, polishing, gear Processing, the worm process, thread processing, ultra-precision machining, bench and scrapers and so on. By material removal rate and machining accuracy distinction can be divided into: ① rough: with large depth of cut, one or a few times by the knife away from the work cut out most or all allowances, such as rough turning, rough planning, Rough milling, drilling and sawing, etc., rough machining precision high efficiency low, generally used as a pre-processing, and sometimes also for final processing. ② Semi-finishing: General roughing and finishing as the middle between the process, but the work piece accuracy and surface roughness on the less demanding position, but also can be used as the final processing.③ finishing: cutting with a fine way to achieve higher machining surface accuracy and surface quality, such as fine cars, fine planning, precision hinges, grinding and so on. General is the final finishing process. ④ Finishing process: after the finish, the aim is to obtain a smaller surface roughness and to slightly improve the accuracy. Finishing processing allowance is small, such as honing, grinding, ultra-precision grinding and super finishing and so on. ⑤ Modification process: the aim is to reduce the surface roughness, to improve the corrosion, dust properties and improve appearance, but does not require higher precision, such as polishing, sanding, etc. ⑥ ultra-precision machining: aerospace, lasers, electronics, nuclear energy and other cutting-edge technologies thatneed some special precision parts, high accuracy over IT4, surface roughness less than Ra microns. This need to take special measures to ultra-precision machining, such as turning mirror, mirror grinding, chemical mechanical polishing of soft abrasive.Distinguished by method of surface machining, the work piece is to rely on the machined surface for cutting tool and the work piece to obtain the relative motion. By surface methods, cutting can be divided into three categories. ① tip trajectory method: relying on the tip relative to the trajectory of the surface to obtain the required work piece surface geometry, such as cylindrical turning, planning surface, cylindrical grinding, with the forming surface, such as by turning mode. The trajectory depends on the tool tip provided by the cutting tool and work piece relative motion. ② forming tool method: short forming method, with the final work piece surface profile that matches the shape forming cutter or grinding wheel, such as processing a shaped surface. At this time forming part of the machine movement was replaced by the blade geometry, such as the shape of turning, milling and forming grinding forming and so on. The more difficult the manufacture of forming cutter, machine - clamp - work piece - tool formed by the process system can withstand the cutting force is limited, forming method is generally used for processing short shaped surface. ③ generating method: also known as rotary cutting method, cutting tool and work piece during processing as a relatively developed into a campaign tool (or wheel) and the work piece instantaneous center line of pure rolling interaction between the two maintain a certain ratio between Is obtained by processing the surface of the blade in this movement in the envelope. Gear machining hobbling, gear shaping, shaving, honing, and grinding teeth (not including form grindingteeth), etc. are generating method processing.PLCEarly called the programmable logic controller PLC (Programmable Logic Controller, PLC), which is mainly used to replace the logic control relays. With the technology, which uses micro-computer technology, industrial control device function has been greatly exceeded the scope of logic control, therefore, such a device today called programmable logic controller, referred to as the PC. However, in order to avoid personal computer (Personal Computer) in the short confusion, it will be referred to as programmable logic controller PLC, plc since 1966, the . Digital Equipment Corporation (DEC) developed there, the current United States, Japan, Germany, PLC Good quality and powerful.The basic structure of Programmable Logic ControllerA. PowerPLC's power in the whole system plays a very important role. If you do not have a good, reliable power system is not working, so the PLC manufacturers design and manufacture of power very seriously. General AC voltage fluctuations of +10% (+15%) range, you can not take other measures to PLC to connect directly to the AC line.processing unit (CPU)Central processing unit (CPU) is the central PLC control. It is given by the function of PLC system program from the programmer receives and stores the user program and data type; check the power supply, memory, I / O and timer alert status,and to diagnose syntax errors in the user program. When the PLC into run-time, first it scans the scene to receive the status of various input devices and data, respectively, into I / O image area, and then one by one from the user program reads the user program memory, after a shell and press Provisions of the Directive the result of logic or arithmetic operations into the I / O image area or data register. And the entire user program is finished, and finally I / O image area of the state or the output of the output register data to the appropriate output device, and so on to run until stopped.To further improve the reliability of PLC, PLC is also large in recent years constitutes a redundant dual-CPU system, or by three voting systems CPU. Thus, even if a CPU fails, the whole system can still work properly.Storage system software of memory called system program memory. Storage application software of memory called the user program memory.and output interface circuit1, the live input interface circuit by the optical coupling circuit and the computer input interface circuit, the role of PLC and field control of an interface for input channels.2, Field output interface circuit by the output data registers, interrupt request strobe circuit and integrated circuit, the role of PLC output interface circuit through the on-site implementation of parts of the output to the field corresponding control signal.moduleSuch as counting, positioning modules.moduleSuch as Ethernet, RS485, Prefab’s-DP communication module.数控系统数控系统是数字控制系统简称,英文名称为Numerical Control System,初期是由硬件电路组成的称为硬件数控(Hard NC),1970年代以后,硬件电路元件慢慢由专用的运算机代替称为运算机数控系统。

数控机床外文文献翻译、中英文翻译

数控机床外文文献翻译、中英文翻译

数控机床外文文献翻译、中英文翻译原文一CNC machine toolsOutdate, J. and Joe, J. Configuration Synthesis of Machining Centers with Tool,JohnWiley & sons, 2001While the specific intention and application for CNC machines vary from one machine type to another, all forms of CNC have common benefits. Here are but a few of the more important benefits offered by CNC equipment.The first benefit offered by all forms of CNC machine tools is improved automation. The operator intervention related to producing work pieces can be reduced or eliminated. Many CNC machines can run unattended during their entire machining cycle, freeing the operator to do other tasks. This gives the CNC user several side benefits including reduced operator fatigue, fewer mistakes caused by human error, and consistent and predictable machining time for each work piece. Since the machine will be running under program control, the skill level required of the CNC operator (related to basic machining practice) is also reduced as compared to a machinist producing work pieces with conventional machine tools.The second major benefit of CNC technology is consistent and accurate work pieces. T oday's CNC machines boast almost unbelievable accuracy and repeatability specifications. This means that once a program is verified, two, ten, or one thousand identical work pieces can be easily produced with precision and consistency.A third benefit offered by most forms of CNC machine toolsis flexibility. Since these machines are run from programs, running a different workpiece is almost as easy as loading a different program. Once a program has been verified and executed for one production run, it can be easily recalled the next time the workpiece is to be run. This leads to yet another benefit, fast change over. Since these machines are very easy to set up and run, and since programs can be easily loaded, they allow very short setup time. This is imperative with today's just-in-time (JIT) product requirements.Motion control - the heart of CNCThe most basic function of any CNC machine is automatic, precise, and consistent motion control. Rather than applying completely mechanical devices to cause motion as is required on most conventional machine tools, CNC machines allow motion control in a revolutionary manner2. All forms of CNC equipment have two or more directions of motion, called axes. These axes can be precisely and automatically positioned along their lengths of travel. The two most common axis types are linear (driven along a straight path) and rotary (driven along a circular path).Instead of causing motion by turning cranks and handwheels as is required on conventional machine tools, CNC machines allow motions to be commanded through programmed commands. Generally speaking, the motion type (rapid, linear, and circular), the axes to move, the amount of motion and the motion rate (federate) are programmable with almost all CNC machine tools.A CNC command executed within the control tells the drive motor to rotate a precise number of times. The rotation of the drive motor in turn rotates the ball screw.And the ball screw drives the linear axis (slide). A feedbackdevice (linear scale) on the slide allows the control to confirm that the commanded number of rotations has taken place3. Refer to fig.1.fig.1 typical drive system of a CNC machine toolThough a rather crude analogy, the same basic linear motion can be found on a common table vise. As you rotate the vise crank, you rotate a lead screw that, in turn, drives the movable jaw on the vise. By comparison, a linear axis on a CNC machine tool is extremely precise. The number of revolutions of the axis drive motor precisely controls the amount of linear motion along the axis.How axis motion is commanded - understanding coordinate systemsIt would be infeasible for the CNC user to cause axis motion by trying to tell each axis drive motor how many times to rotate in order to command a given linear motion amount4. (This would be like having to figure out how many turns of the handle on a table vise will cause the movable jaw to move exactly one inch!) Instead, all CNC controls allow axis motion to be commanded in a much simpler and more logical way by utilizing some form of coordinate system. The two most popular coordinate systems used with CNC machines are the rectangular coordinate system and the polar coordinate system. By far, the more popular of these two is the rectangular coordinate system.The program zero point establishes the point of reference for motion commands in a CNC program. This allows the programmer to specify movements from a common location. If program zero is chosen wisely, usually coordinates needed forthe program can be taken directly from the print.With this technique, if the programmer wishes the tool to be sent to a position one inch to the right of the program zero point, X1.0 is commanded. If the programmer wishes the tool to move to a position one inch above the program zero point, Y1.0 is commanded. The control will automatically determine how many times to rotate each axis drive motor and ball screw to make the axis reach the commanded destination point . This lets the programmer command axis motion in a very logical manner. Refer to fig.2, 3.fig.2, 3.Understanding absolute versus incremental motionAll discussions to this point assume that the absolute mode of programming is used6. The most common CNC word used to designate the absolute mode is G90. In the absolute mode, the end points for all motions will be specified from the program zero point. For beginners, this is usually the best and easiest method of specifying end points for motion commands. However, there is another way of specifying end points for axis motion.In the incremental mode (commonly specified by G91), endpoints for motions are specified from the tool's current position, not from program zero. With this method of commanding motion, the programmer must always be asking "How far should I move the tool?" While there are times when the incremental mode can be very helpful, generally speaking, this is the more cumbersome and difficult method of specifying motion and beginners should concentrate on using the absolute mode.Be careful when making motion commands. Beginners have the tendency to think incrementally. If working in the absolute mode (as beginners should), the programmer should always be asking "To what position should the tool be moved?" This position is relative to program zero, NOT from the tools current position.Aside from making it very easy to determine the current position for any command, another benefit of working in the absolute mode has to do with mistakes made during motion commands. In the absolute mode, if a motion mistake is made in one command of the program, only one movement will be incorrect. On the other hand, if a mistake is made during incremental movements, all motions from the point of the mistake will also be incorrect.Assigning program zeroKeep in mind that the CNC control must be told the location of the program zero point by one means or another. How this is done varies dramatically from one CNC machine and control to another8. One (older) method is to assign program zero in the program. With this method, the programmer tells the control how far it is from the program zero point to the starting position of the machine. This is commonly done with a G92 (or G50) command at least at the beginning of the program and possiblyat the beginning of each tool.Another, newer and better way to assign program zero is through some form of offset. Refer to fig.4. Commonly machining center control manufacturers call offsets used to assign program zero fixture offsets. Turning center manufacturers commonly call offsets used to assign program zero for each tool geometry offsets.fig.4 assign program zero through G54Flexible manufacturing cellsA flexible manufacturing cell (FMC) can be considered as a flexible manufacturing subsystem. The following differences exist between the FMC and the FMS:1.An FMC is not under the direct control of thecentral computer. Instead, instructions from the centralcomputer are passed to the cell controller.2.The cell is limited in the number of part families itcan manufacture.The following elements are normally found in an FMC:Cell controllerProgrammable logic controller (PLC)More than one machine toolA materials handling device (robot or pallet)The FMC executes fixed machining operations with parts flowing sequentially between operations.High speed machiningThe term High Speed Machining (HSM) commonly refers to end milling at high rotational speeds and high surface feeds. For instance, the routing of pockets in aluminum airframe sections with a very high material removal rate1. Refer to fig.5 for the cutting data designations and for mulas. Over the past 60 years, HSM has been applied to a wide range of metallic and non-metallic workpiece materials, including the production of components with specific surface topography requirements and machining of materials with hardness of 50 HRC and above. With most steel components hardened to approximately 32-42 HRC, machining options currently include:Fig.5 cutting datarough machining and semi-finishing of the material in its soft (annealed) condition heat treatment to achieve the final required hardness = 63 HRC machining of electrodes and Electrical Discharge Machining (EDM) of specific parts of dies and moulds (specifically small radii and deep cavities with limited accessibility for metal cutting tools) finishing and super-finishing of cylindrical/flat/cavity surfaces with appropriate cemented carbide, cermets, solid carbide, mixed ceramic or polycrystalline cubic boron nitride (PCBN)For many components, the production process involves acombination of these options and in the case of dies and moulds it also includes time consuming hand finishing. Consequently, production costs can be high and lead times excessive.It is typical in the die and mould industry to produce one or just a few tools of the same design. The process involves constant changes to the design, and because of these changes there is also a corresponding need for measuring and reverse engineering.The main criteria are the quality level of the die or mould regarding dimensional, geometric and surface accuracy. If the quality level after machining is poor and if it cannot meet the requirements, there will be a varying need of manual finishing work. This work produces satisfactory surface accuracy, but it always has a negative impact on the dimensional and geometric accuracy.One of the main aims for the die and mould industry has been, and still is, to reduce or eliminate the need for manual polishing and thus improve the quality and shorten the production costs and lead times.Main economical and technical factors for the development of HSMSurvivalThe ever increasing competition in the marketplace is continually setting new standards. The demands on time and cost efficiency is getting higher and higher. This has forced the development of new processes and production techniques to take place. HSM provides hope and solutions...MaterialsThe development of new, more difficult to machine materials has underlined the necessity to find new machining solutions.The aerospace industry has its heat resistant and stainless steel alloys. The automotive industry has different bimetal compositions, Compact Graphite Iron and an ever increasing volume of aluminum3. The die and mould industry mainly has to face the problem of machining high hardened tool steels, from roughing to finishing.QualityThe demand for higher component or product quality is the result of ever increasing competition. HSM, if applied correctly, offers a number of solutions in thisarea. Substitution of manual finishing is one example, which is especially important on dies and moulds or components with a complex 3D geometry.ProcessesThe demands on shorter throughput times via fewer setups and simplified flows (logistics) can in most cases, be solved by HSM. A typical target within the die and mould industry is to completely machine fully hardened small sized tools in one setup. Costly and time consuming EDM processes can also be reduced or eliminated with HSM.Design & developmentOne of the main tools in today's competition is to sell products on the value of novelty. The average product life cycle on cars today is 4 years, computers and accessories 1.5 years, hand phones 3 months... One of the prerequisites of this development of fast design changes and rapid product development time is the HSM technique.Complex productsThere is an increase of multi-functional surfaces on components, such as new design of turbine blades giving newand optimized functions and features. Earlier designs allowed polishing by hand or with robots (manipulators). Turbine blades with new, more sophisticated designs have to be finished via machining and preferably by HSM . There are also more and more examples of thin walled workpiece that have to be machined (medical equipment, electronics, defense products, computer parts).Production equipmentThe strong development of cutting materials, holding tools, machine tools, controls and especially CAD/CAM features and equipment, has opened possibilities that must be met with new production methods and techniques5.Definition of HSMSalomon's theory, "Machining with high cutting speeds..." on which, in 1931, took out a German patent, assumes that "at a certain cutting speed (5-10 times higher than in conventional machining), the chip removal temperature at the cutting edge will start to decrease...".See fig.6.Fig.6 chip removal temperature as a result of the cutting speedGiven the conclusion:" ... seems to give a chance to improve productivity in machining with conventional tools at high cutting speeds..."Modern research, unfortunately, has not been able to verifythis theory totally. There is a relative decrease of the temperature at the cutting edge that starts at certain cutting speeds for different materials.The decrease is small for steel and cast iron. But larger for aluminum and other non-ferrous metals. The definition of HSM must be based on other factors.Given today's technology, "high speed" is generally accepted to mean surface speeds between 1 and 10 kilometers perminute, or roughly 3 300 to 33 000 feet per minute. Speeds above 10 km/min are in the ultra-high speed category, and are largely the realm of experimental metal cutting. Obviously, the spindle rotations required to achieve these surface cutting speeds are directly related to the diameter of the tools being used. One trend which is very evident today is the use of very large cutter diameters for these applications - and this has important implications for tool design.There are many opinions, many myths and many different ways to define HSM. Maintenance and troubleshooting Maintenance for a horizontal MCThe following is a list of required regular maintenance for a Horizontal Machining Center as shown in fig.7. Listed are the frequency of service, capacities, and type of fluids required. These required specifications must be followed in order to keep your machine in good working order and protect your warranty.Fig. 7 horizontal machining centerDailyTop off coolant level every eight hour shift (especially during heavy TSC usage).Check way lube lubrication tank level.Clean chips from way covers and bottom pan.Clean chips from tool changer.Wipe spindle taper with a clean cloth rag and apply light oil.WeeklyCheck for proper operation of auto drain on filter regulator. See fig. 8Fig. 8 way lube and pneumaticsOn machines with the TSC option, clean the chip basket on the coolant tank.Remove the tank cover and remove any sediment inside the tank. Be careful to disconnect the coolant pump from the controller and POWER OFF the control before working on the coolant tank. Do this monthly for machines without the TSC option.Check air gauge/regulator for 85 psi.For machines with the TSC option, place a dab of grease on the V-flange of tools. Do this monthly for machines without the TSC option.Clean exterior surfaces with mild cleaner. DO NOT usesolvents.Check the hydraulic counterbalance pressure according to the machine's specifications.Place a dab of grease on the outside edge of the fingers of the tool changer and run through all tools".MonthlyCheck oil level in gearbox. Add oil until oil begins dripping from over flow tube at bottom of sump tank.Clean pads on bottom of pallets.Clean the locating pads on the A-axis and the load station. This requires removing the pallet.Inspect way covers for proper operation and lubricate with light oil, if necessary.Six monthsReplace coolant and thoroughly clean the coolant tank.Check all hoses and lubrication lines for cracking.AnnuallyReplace the gearbox oil. Drain the oil from the gearbox, and slowly refill it with 2 quarts of Mobil DTE 25 oil.Check oil filter and clean out residue at bottom for the lubrication chart.Replace air filter on control box every 2 years.Mineral cutting oils will damage rubber based components throughout the machine.TroubleshootingThis section is intended for use in determining the solution to a known problem. Solutions given are intended to give the individual servicing the CNC a pattern to follow in, first, determining the problem's source and, second, solving the problem.Use common senseMany problems are easily overcome by correctly evaluating the situation. All machine operations are composed of a program, tools, and tooling. You must look at all three before blaming one as the fault area. If a bored hole is chattering because of an overextended boring bar, don't expect the machine to correct the fault.Don't suspect machine accuracy if the vise bends the part. Don't claim hole miss-positioning if you don't first center-drill the hole.Find the problem firstMany mechanics tear into things before they understand the problem, hoping that it will appear as they go. We know this from the fact that more than half of all warranty returned parts are in good working order. If the spindle doesn't turn, remember that the spindle is connected to the gear box, which is connected to the spindle motor, which is driven by the spindle drive, which is connected to the I/O BOARD, which is driven by the MOCON, which is driven by the processor. The moral here is doing replace the spindle drives if the belt is broken. Find the problem first; don't just replace the easiest part to get to.Don tinker with the machineThere are hundreds of parameters, wires, switches, etc., that you can change in this machine. Don't start randomly changing parts and parameters. Remember, there is a good chance that if you change something, you will incorrectly install it or break something else in the process6. Consider for a moment changing the processor's board. First, you have to download all parameters, remove a dozen connectors, replace the board, reconnect and reload, and if you make one mistake or bend one tiny pin itWON'T WORK. You always need to consider the risk of accidentally damaging the machine anytime you work on it. It is cheap insurance to double-check a suspect part before physically changing it. The less work you do on the machine the better.译文一数控机床虽然各种数控机床的功能和应用各不相同,但它们有着共同的优点。

数控技术 外文翻译 外文文献 英文文献

数控技术 外文翻译 外文文献 英文文献

外文翻译NUMERICAL CONTROLNumerical control(N/C)is a form of programmable automation in which the processing equipment is controlled by means of numbers,letters,and other symbols.The numbers,letters,and symbols are coded in an appropriate format to define a program of instructions for a particular work part or job.When the job changes,the program of instructions is changed.The capability to change the program is what makes N/C suitable for low-and medium-volume production.It is much easier to write programs th an to make major alterations of the processing equipment.There are two basic types of numerically controlled machine tools:point—to—point and continuous—path(also called contouring).Point—to—point machines use unsynchronized motors,with the result that the position of the machining head Can be assured only upon completion of a movement,or while only one motor is running.Machines of this type are principally used for straight—line cuts or for drilling or boring.The N/C system consists of the following comp onents:data input,the tape reader with the control unit,feedback devices,and the metal—cutting machine tool or other type of N/C equipment.Data input,also called “man—to—control link”,may be provided to the machine tool manually,or entirely by automatic means.Manual methods when used as the sole source of input data are restricted to a relatively small number of inputs.Examples of manually operated devices are keyboard dials,pushbuttons,switches,or thumbwheel selectors.These are located on a console near t he machine.Dials ale analog devices usually connected to a syn-chro-type resolver or potentiometer.In most cases,pushbuttons,switches,and other similar types of selectors aye digital input devices.Manual input requires that the operator set the controls fo r each operation.It is a slow and tediousprocess and is seldom justified except in elementary machining applications or in special cases.In practically all cases,information is automatically supplied to the control unit and the machine tool by cards,punched tapes,or by magnetic tape.Eight—channel punched paper tape is the most commonly used form of data input for conventional N/C systems.The coded instructions on the tape consist of sections of punched holes called blocks.Each block represents a machine function,a machining operation,or a combination of the two.The entire N/C program on a tape is made up of an accumulation of these successive data blocks.Programs resulting in long tapes all wound on reels like motion-picture film.Programs on relatively short tapes may be continuously repeated by joining the two ends of the tape to form a loop.Once installed,the tape is used again and again without further handling.In this case,the operator simply loads and unloads the parts.Punched tapes ale prepared on typ e writers with special tape—punching attachments or in tape punching units connected directly to a computer system.Tape production is rarelyerror-free.Errors may be initially caused by the part programmer,in card punching or compilation,or as a result of physical damage to the tape during handling,etc.Several trial runs are often necessary to remove all errors and produce an acceptable working tape.While the data on the tape is fed automatically,the actual programming steps ale done manually.Before the coded tape may be prepared,the programmer,often working with a planner or a process engineer, must select the appropriate N/C machine tool,determine the kind of material to be machined,calculate the speeds and feeds,and decide upon the type of tooling needed. The dimensions on the part print are closely examined to determine a suitable zero reference point from which to start the program.A program manuscript is then written which gives coded numerical instructions describing the sequence ofoperations that the machine tool is required to follow to cut the part to the drawing specifications.The control unit receives and stores all coded data until a complete block of information has been accumulated.It then interprets the coded instruction and directs the machine tool through the required motions.The function of the control unit may be better understood by comparing it to the action of a dial telephone,where,as each digit is dialed,it is stored.When the entire number has been dialed,the equipment becomes activated and the call is completed.Silicon photo diodes,located in the tape reader head on the control unit,detect light as it passes through the holes in the moving tape.The light beams are converted to electrical energy,which is amplified to further strengthen the signal.The signals are then sent to registers in the control unit, where actuation signals are relayed to the machine tool drives.Some photoelectric devices are capable of reading at rates up to 1000 characters per second.High reading rates are necessary to maintain continuous machine—tool motion;otherwise dwell marks may be generated by the cutter on the part during contouring operations.The reading device must be capable of reading data blocks at a rate faster than the control system can process the data.A feedback device is a safeguard used on some N/C installations to constantly compensate for errors between the commanded position and the actual location of the moving slides of the machine tool.An N /C machine equipped with this kind of a direct feedback checking device has what is known as a closed-loop system.Positioning control is accomplished by a sensor which,during the actual operation,records the position of the slides and relays this information back to the control unit.Signals thus received ale compared to input signals on the tape,and any discrepancy between them is automatically rectified.In an alternative system,called an open—loop system,the machine is positioned solely by stepping motor drives in response to commands by a controllers.There are three basic types of NC motions, as follows: Point-to-point or Positional Control In point-to-point control the machine tool elements (tools, table, etc.) are moved to programmed locations and the machining operations performed after the motion s are completed. The path or speed of movement between locations is unimportant; only the coordinates of the end points of the motions are accurately controlled. This type of control is suitable for drill presses and some boring machines, where drilling, t apping, or boring operations must be performed at various locations on the work piece. Straight-Line or Linear Control Straight-Line control systems are able to move the cutting tool parallel to one of the major axes of the machine tool at a controlled rate suitable for machining. It is normally only possible to move in one direction at a time, so angular cuts on the work piece are not possible, consequently, for milling machines, only rectangular configurations can be machined or for lathes only surfaces parall el or perpendicular to the spindle axis can be machined. This type of controlled motion is often referred to as linear control or a half-axis of control. Machines with this form of control are also capable ofpoint-to-point control.Continuous Path or Contouring Control In continuous path control the motions of two or more of the machine axes are controlled simultaneously, so that the position and velocity of the can be tool are changed continuously. In this way curves and surfaces can be machined at a controlled feed rate. It is the function of the interpolator in the controller to determine the increments of the individual controlled axes of the machines necessary to produce the desired motion. This type of control is referred to as continuous control or a full axis of control.Some terminology concerning controlled motions for NC machines has been introduced. For example, some machines are referred to asfour-or five-or even six-axis machines. For a vertical milling machine three axes of control are fairly obvious, these being the usual X, Y, Z coordinate directions. A fourth or fifth axis of control would imply some form of rotary table to index the work piece or possibly to provide angular motion of the work head. Thus, in NC terminology an axis of control is any controlled motion of the machine elements (spindles, tables, etc). A further complication is use of the term half-axis of control; for example, many milling machines are referred to as 2.5-axis machine. This means that continuous control is possib le for two motions (axes) and only linear control is possible for the third axis. Applied to vertical milling machines, 2.5axis control means contouring in the X, Y plane and linear motion only in the Z direction. With these machines three-dimensional objects have to be machined with water lines around the surface at different heights. With an alternative terminology the same machine could be called a 2CL machine (C for continuous, L for linear control). Thus, a milling machine with continuous control in th e X, Y, Z directions could be termed be a three-axis machine or a 3c machine, Similarly, lathes are usually two axis or 2C machines. The degree of work precision depends almost entirely upon the accuracy of the lead screw and the rigidity of the machine st ructure.With this system.there is no self-correcting action or feedback of information to the control unit.In the event of an unexpected malfunction,the control unit continues to put out pulses of electrical current.If,for example,the table on a N/C milling machine were suddenly to become overloaded,no response would be sent back to the controller.Because stepping motors are not sensitive to load variations,many N/C systems are designed to permit the motors to stall when the resisting torque exceeds the motor torque.Other systems are in use,however,which in spite of the possibility of damage to the machine structure or to the mechanical system,ale designed with special high—torque steppingmotors.In this case,the motors have sufficient capacity to “overpower” the system in the event of almost any contingency.The original N/C used the closed—loop system.Of the two systems,closed and open loop,closed loop is more accurate and,as a consequence,is generally more expensive.Initially,open—loop systems were used almost entirely for light-duty applications because of inherent power limitations previously associated with conventional electric stepping motors.Recent advances in the development of electro hydraulic stepping motors have led to increasingly heavier machin e load applications.数控技术数控是可编程自动化技术的一种形式,通过数字、字母和其他符号来控制加工设备。

数控技术 外文翻译 外文文献 英文文献 数控技术的发展与维修

数控技术 外文翻译 外文文献 英文文献 数控技术的发展与维修

Development and maintenance of CNC technology Numerical control technology and equipment is the development of new high-tech industry and cutting-edge enabling technology, industry and the most basic equipment. The world information industry, biological industry, aviation, aerospace and other defense industry widely used numerical techniques to improve manufacturing capacity and level, to improve the adaptability of the market and competitiveness. Industrial countries and CNC numerical control technology and equipment will also be listed as countries of strategic materials, not only to develop their own numerical control technology and industry, and in "sophisticated" technology and equipment, numerical control key aspects of the policy of closures and restrictions. Therefore, efforts to develop advanced numerical control technology as the core manufacturing technology has become the world's developed countries to accelerate economic development, enhance the comprehensive national strength and an important way to statehood.Part I: the development of CNC machine tools trends in individual1. High speed, high accuracy, high reliabilityHigh speed: To improve the speed and increase feed spindle speed.High precision: the precision from micron to sub-micron level, and even the nano-level (high reliability: the reliability of numerical control system generally higher than the reliability of numerical control equipment more than an order of magnitude, but not the higher the better reliability because the goods by the cost performance constraints.2. CompositeComposite function CNC machine tool development, its core is in a single machine to complete the turning, milling, drilling, tapping, reaming and reaming and other operating procedures, thereby increasing the efficiency and precision machine tools to improve production flexibility.3. IntelligentIntelligent content included in all aspects of the numerical control system: the pursuit of processing efficiency and processing quality of intelligence; to improve the performance and the use of convenient connections and other aspects of intelligence; simplify programming, simplifying operational intelligence; also like the intelligent automatic programming, intelligent man-machine interface, as well as intelligent diagnostics, intelligent monitoring and other aspects, to facilitate system diagnostics and maintenance.4. Flexible, integratedThe world of CNC machine tools to the development trend of flexible automation systems are: from the point (CNC single, composite machining centers and CNC machine tools), line (FMC, FMS, FTL, FML) to the surface (Section workshop independent manufacturing island FA) , body (CIMS, distributed network integrated manufacturing system) direction, the other to focus on applied and economic direction. Flexible automation technology is the industry to adapt to dynamic market demands and quickly update the primary means of product is the main trend of national manufacturing industry is the basis for the field of advanced manufacturing technology.Second, personalization is the adaptability of the market trendsToday's market, gradually formed the pattern of international cooperation, the products becoming more competitive, efficient and accurate processing of the escalating demand means, the user's individual requirements become increasingly strong, professional, specialization, more and more high-tech machine tools by the users of all ages.Third, the open architecture trend isThe core of a new generation of CNC system development is open. Open software platform and hardware platforms are open systems, modular, hierarchical structure, and through out the form to provide a unified application interface.CNC system to address the closure of the traditional CNC applications and industrial production problems. At present, many countries of open CNC system, CNC system has become an open numerical control system of the future of the road. The open numerical control system architecture specification, communication specifications, configuration specifications, operating platform, function libraries and CNC numerical control system software development tools, system function is the core of the current study. Network numerical control equipment is nearly two years of a new focus. NC network equipment will greatly satisfy the production lines, manufacturing systems, manufacturing information integration needs of enterprises, but also achieve new manufacturing model, such as agile manufacturing, virtual enterprises, global manufacturing the base unit. Some well-known at home and abroad, and CNC CNC machine tools manufacturing company inPart II: Machine MaintenanceCNC machine tools is electronic technology, measurement technology, automation technology, semiconductor technology, computer technology and electrical technology, and integrated set of automation equipment, high precision, high efficiency and high flexibility. CNC machine tools is a process control equipment and asked him in real-time control of the accuracy of every moment of work, any part of the fault and failure, so that the machine will shut down, resulting in production stoppages, which seriously affected and restricted the production efficiency . CNC machine tools in many industries to work the device is critical, if not after a failure in its maintenance and troubleshooting time, it will cause greater economic losses. Therefore, the principle that complex numerical control system, structure, maintenance of sophisticated equipment is necessary. CNC machine tools to enhance fault diagnosis and maintenance of power, can improve the reliability of CNC machine tools, CNC machine tools is conducive to the promotion and use.CNC machine tools is a mechanical, electrical, hydraulic, gas combination of complex equipment, though the reasons for failure vary, but the failure occurred, the general idea of the steps are the same. Fails,Spindle start below to stop immediately after the fault diagnosis of CNC machine tools as an example the general process.First, the fault-site investigation. The survey content includes 1, 2 types of failure, the failure frequency of 3, 4, external conditions, the operating conditions 5, 6, machine conditions, the functioning of 7, wiring between machine tools and systems 8, CNC equipment visual inspection. After an investigation, such failure is spindle class failure, only once, outside of all normal, the operator of a boot to reflect this situation.Second, the fault information collation, analysis. For some simple fault, because not alot of time, the method can be used form of logical reasoning, analysis, identification and troubleshooting. After a failed on-site investigation for several reasons we suspect that the system output pulse ①②drive is not enough time to move the state line to control the spindle components ③④damage to the spindle motor short-circuit, causing the spindle thermal relay protection ⑤ not with self-control loop lock circuits, and the parameter is set to pulse signal output, so that the spindle can not operate normally. Identify possible reasons to rule out one by one.Third, conduct fault diagnosis and troubleshooting.Diagnosis usually follows the following principles: 1, after the first outside inside. Reliable line of modern CNC system increasingly high failure rate of CNC system itself less and less, and most are non-occurrence of failure causes the system itself. The CNC machine is a mechanical, hydraulic, electrical as one of the tools, the occurrence of the fault will be reflected by these three comprehensive, maintenance personnel should be from outside to inside one by one investigation to avoid arbitrary unsealed, demolition, otherwise expand the malfunction, so that the loss of precision machine tools, slow performance, outside the system detected the fault is due to open one by one, hydraulic components, pneumatic components, electrical actuators, mechanical devices caused problems. 2, the first after the electrical machinery. In general, the mechanical failure easier to find, and numerical control system and electrical fault diagnosis more difficult, before the troubleshooting to rule out mechanical failure of the first 3, after the first static dynamic. Power off the machine first, quiescent state, through understanding, observation, testing, analysis, confirm the power failure will not result in expansion of the incident only after the power to the machine, run the state, the dynamic of observation, inspection and testing, to find fault. While after the devastating power failure, you must first rule out the danger, before electricity. 4, after the first simple and complex. When multiple failures are intertwined, and sometimes impossible to start with, we should first solve the problem easily, then solve the difficult problem, often a simple problem to solve, the difficulty of the problem may also become easier.CNC machine tools in the fault detection process, should make full use of numerical control system self-diagnostic features to be judged, but also flexibility in the use of some common troubleshooting methods. Troubleshooting common methods are:1. Routine examination methodRoutine examination method is mainly of hands, eyes, ears, nose and other organs of the fault occurrence of various light, sound, smell and abnormal observations and careful look at every system, follow the "first post outside of" the principle of fault diagnosis by looking, listening, smelling, asking, mold and so on, from outside to inside one by one check, the fault can often be narrowed down to a module or a printed circuit board. This requires maintenance personnel have a wealth of practical experience, to the wider multidisciplinary and comprehensive knowledge of the ability to judge.2. Self-diagnostic function methodModern CNC system has yet to achieve a high degree of intelligence. But already has a strong self-diagnostic function. CNC ready to monitor the hardware and software is working. Once the abnormal, immediately displayed on the CRT alarm or fault LEDs indicate the approximate cause. Using self-diagnosis function, but also shows the interface signals between the system and the host state, in order to determine the fault occurred in themechanical part or parts of NC system, and indicate the approximate fault location. This method is currently the most effective maintenance methods.3. Functional program testing methodSo-called functional program testing method is commonly used in the numerical control system functions and special features, such as linear positioning, circular interpolation, helical cut, fixed cycle, such as the user macro programming by hand or automatic programming methods, the preparation of test procedures into a functional program , into the numerical control system, and then start the CNC system to make it run, to check the im time the first boot of CNC whether a programming error or operational error or machine4. Spare parts substitutionSpare parts replacement method is a simple method to determine the scene is one of the most commonly used. The so-called spare substitution is generally the cause of failure in the analysis of the case, maintenance personnel can use the alternate PCB, templates, integrated circuit chip or replace the questionable parts of components, which narrowed the fault to a printed circuit board or chip level. It is actually in the verification analysis is correct. However, before switching the standby board should carefully check the spare board is intact, and should check the status of reserve board should be fully consistent with the original board the state. This includes checking with the board selection switch, set the location and the short rod potentiometer position. In short, we must strictly in accordance with the system's operation, maintenance requirements manual operation.In determining the replacement of a part to, should carefully check the relevant connected to electrical lines and other related, confirming that no failure up to the new replacement to prevent failures caused by external damage to replace the parts up.5. Transfer ActThe so-called transfer method is to have the same numerical control system features two printed circuit boards, templates, integrated circuit chips or components to exchange, observed failure phenomena be transferred. In this way, the system can quickly determine the fault position. This method is actually a kind of spare parts substitution. Therefore, the considerations described in the same spare parts substitution.6. Parameter check methodKnown parameters can directly affect the numerical performance of CNC machine tools. Parameters are usually stored in the magnetic bubble memory, or stored in batteries to be maintained by the CMOS RAM, once the battery is low or because of outside interference and other factors, some parameters will be lost or change in chaos, so that the machine does not work. At this point, through the proofreading, correction parameters, will be able to troubleshoot. When the machine idle for a long time to work again for no reason that there is no normal or failure without warning, it should be based on fault characteristics, inspection and proof-reading the relevant parameters.After a long run of CNC machine tools, wear and tear due to its mechanical drive components, electrical component performance changes and other reasons, also need to adjust the parameters of its. Some machine tool failure is often not timely because the parameters change due to some not meet. Of course, these failures are the fault of the areas are soft.7. Measurement of Comparative LawCNC system in the design of printed circuit board manufacturing plant, in order to adjust, repair facilities, in the printed circuit board designed a number of test terminals. Users can also use normal printed circuit board terminals comparing the measured and the difference between the printed circuit board failure. These terminals can detect the voltage and waveform measurements, analyze the causes of failure and failure location. Even on a normal printed circuit board can sometimes artificially create "fault", such as broken connection or short circuit, unplug the components, in order to determine the real cause of failure. Therefore, maintenance personnel should be in the usual accumulation of key parts of the printed circuit board or failure-prone parts of the right in the normal waveform and voltage values. Because the CNC system manufacturer often does not provide the information in this regard.8. Percussion methodWhen the CNC system failures showed Ruoyouruowu, often used method for detecting the fault struck the site lies. This is because the numerical control system is composed by the multi-block printed circuit boards, each board has a lot of solder joints, plates or between modules and is connected through the connectors and cables. Therefore, any cold solder joint or bad, may cause a malfunction. When the tap with the insulation and poor contact with Weld doubt at fault must be repeated reproduction.9. Local heating methodAfter a long running CNC system components are to be aging, performance will deteriorate. When they are not fully damaged, failures will become from time to time. Then heat can be used such as a hair dryer or electric iron is suspected to local heating components, accelerating the aging so thoroughly exposed fault components. Of course, using this method, be sure to pay attention to components of the temperature parameters, do not roast the original device is a good or bad.10. Principle of analysisThe composition according to principles of numerical control system can be analyzed from various points of logical levels and logical parameters (such as voltage or waveform) and then with a multimeter, logic pen, only the oscilloscope or logic analyzer to measure, analyze and compare, and thus failure positioning. Using this method, which requires maintenance personnel to be on the whole system or the principle of each circuit have a clear, deep understanding.Based on the above principles and methods, we may be itemized on the check it and eliminate the causes.The first possible failure for the system output pulse time is not enough, we adjust the M-code system, start the spindle output time, found the problem still exists, and then find the next possible cause may be in the drive to move the state, refer to the manual drive , set parameters start the spindle, the problem still exists we suspected spindle motor short-circuit, resulting in thermal relay protection. Then find the cause of the short, so that the spindle thermal relay reset the start and found that the normal operation of the spindle, the problem solved.Fourth, do a lessons learned and recorded. After troubleshooting, repair work can not be considered complete, still need technical and management aspects of the underlying causes of failure have to take appropriate measures to prevent failures from happening again. Underfield conditions when necessary use of mature technologies to transform and improve the equipment. Finally, the failure of the maintenance of the phenomenon, cause analysis, resolution process, the replacement of components, legacy, etc. to make a record.数控技术的发展与维修数控技术及装备是发展新兴高新技术产业和尖端工业的使能技术和最基本的装备。

机械类数控车床外文翻译外文文献英文文献车床.doc

机械类数控车床外文翻译外文文献英文文献车床.doc

LathesLathes are machine tools designed primarily to do turning, facing and boring, Very little turning is done on other types of machine tools, and none can do it with equal facility. Because lathes also can do drilling and reaming, their versatility permits several operations to be done with a single setup of the work piece. Consequently, more lathes of various types are used in manufacturing than any other machine tool.The essential components of a lathe are the bed, headstock assembly, tailstock assembly, and the leads crew and feed rod.The bed is the backbone of a lathe. It usually is made of well normalized or aged gray or nodular cast iron and provides s heavy, rigid frame on which all the other basic components are mounted. Two sets of parallel, longitudinal ways, inner and outer, are contained on the bed, usually on the upper side. Some makers use an inverted V-shape for all four ways, whereas others utilize one inverted V and one flat way in one or both sets, They are precision-machined to assure accuracy of alignment. On most modern lathes the way are surface-hardened to resist wear and abrasion, but precaution should be taken in operating a lathe to assure that the ways are not damaged. Any inaccuracy in them usually means that the accuracy of the entire lathe is destroyed.The headstock is mounted in a foxed position on the inner ways, usually at the left end of the bed. It provides a powered means of rotating the word at various speeds . Essentially, it consists of a hollow spindle, mounted in accurate bearings, and a set of transmission gears-similar to a truck transmission—through which the spindle can be rotated at a number of speeds. Most lathes provide from 8 to 18 speeds, usually in a geometric ratio, and on modern lathes all the speeds can be obtained merely by moving from two to four levers. An increasing trend is to provide a continuously variable speed range through electrical or mechanical drives.Because the accuracy of a lathe is greatly dependent on the spindle, it is of heavy construction and mounted in heavy bearings, usually preloaded tapered roller or ball types. The spindle has a hole extending through its length, through which long bar stock can be fed. The size of maximum size of bar stock that can be machined when the material must be fed through spindle.The tailsticd assembly consists, essentially, of three parts. A lower casting fits on the inner ways of the bed and can slide longitudinally thereon, with a means for clamping the entire assembly in any desired location, An upper casting fits on the lower one and can be moved transversely upon it, on some type of keyed ways, to permit aligning the assembly is the tailstock quill. This is a hollow steel cylinder, usually about 51 to 76mm(2to 3 inches) in diameter, that can be moved several inches longitudinally in and out of the upper casting by means of a hand wheel and screw.The size of a lathe is designated by two dimensions. The first is known as the swing. This is the maximum diameter of work that can be rotated on a lathe. It is approximately twice the distance between the line connecting the lathe centers and the nearest point on the ways, The second size dimension is the maximum distance between centers. The swing thus indicates the maximum work piece diameter that can be turned in the lathe, while the distance between centers indicates the maximum length of work piece that can be mounted between centers.Engine lathes are the type most frequently used in manufacturing. They are heavy-duty machine tools with all the components described previously and have power drive for all tool movements except on the compound rest. They commonly range in size from 305 to 610 mm(12 to 24 inches)swing and from 610 to 1219 mm(24 to 48 inches) center distances, but swings up to 1270 mm(50 inches) and center distances upto 3658mm(12 feet) are not uncommon. Most have chip pans and a built-in coolant circulating system. Smaller engine lathes-with swings usually not over 330 mm (13 inches ) –also are available in bench type, designed for the bed to be mounted on a bench on a bench or cabinet.Although engine lathes are versatile and very useful, because of the time required for changing and setting tools and for making measurements on the work piece, thy are not suitable for quantity production. Often the actual chip-production tine is less than 30% of the total cycle time. In addition, a skilled machinist is required for all the operations, and such persons are costly and often in short supply. However, much of the operator’s time is consumed by simple, repetitious adjustments and in watching chips being made. Consequently, to reduce or eliminate the amount of skilled labor that is required, turret lathes, screw machines, and other types of semiautomatic and automatic lathes have been highly developed and are widely used in manufacturing.2 Numerical ControlOne of the most fundamental concepts in the area of advanced manufacturing technologies is numerical control (NC). Prior to the advent of NC, all machine tools ere manually operated and controlled. Among the many limitations associated with manual control machine tools, perhaps none is more prominent than the limitation of operator skills. With manual control, the quality of the product is directly related to and limited to the skills of the operator. Numerical control represents the first major step away from human control of machine tools.Numerical control means the control of machine tools and other manufacturing systems through the use of prerecorded, written symbolic instructions. Rather than operating a machine tool, an NC technician writes a program that issues operational instructions to the machine tool. For a machine tool to be numerically controlled, it must be interfaced with a device for accepting and decoding the programmed instructions, known as a reader.Numerical control was developed to overcome the limitation of human operators, and it has done so. Numerical control machines are more accurate than manually operated machines, they can produce parts more uniformly, they are faster, and the long-run tooling costs are lower. The development of NC led to the development of several other innovations in manufacturing technology:Electrical discharge machining,Laser cutting,Electron beam welding.Numerical control has also made machine tools more versatile than their manually operated predecessors. An NC machine tool can automatically produce a wide of parts, each involving an assortment of widely varied and complex machining processes. Numerical control has allowed manufacturers to undertake the production of products that would not have been feasible from an economic perspective using manually controlled machine tolls and processes.Like so many advanced technologies, NC was born in the laboratories of the Massachusetts Institute of Technology. The concept of NC was developed in the early 1950s with funding provided by the U.S. Air Force. In its earliest stages, NC machines were able to made straight cuts efficiently and effectively.However, curved paths were a problem because the machine tool had to be programmed to undertake a series of horizontal and vertical steps to produce a curve. The shorter the straight lines making up the steps, the smoother is the curve, Each line segment in the steps had to be calculated.This problem led to the development in 1959 of the Automatically Programmed Tools (APT) language. This is a special programming language for NC that uses statements similar to English language to define the part geometry, describe the cutting tool configuration, and specify the necessary motions. The development of the APT language was a major step forward in the fur ther development from those used today. The machines had hardwired logic circuits. The instructional programs were written on punchedpaper, which was later to be replaced by magnetic plastic tape. A tape reader was used to interpret the instructions written on the tape for the machine. Together, all of this represented a giant step forward in the control of machine tools. However, there were a number of problems with NC at this point in its development.A major problem was the fragility of the punched paper tape medium. It was common for the paper tape containing the programmed instructions to break or tear during a machining process. This problem was exacerbated by the fact that each successive time a part was produced on a machine tool, the paper tape carrying the programmed instructions had to be rerun through the reader. If it was necessary to produce 100 copies of a given part, it was also necessary to run the paper tape through the reader 100 separate tines. Fragile paper tapes simply could not withstand the rigors of a shop floor environment and this kind of repeated use.This led to the development of a special magnetic plastic tape. Whereas the paper carried the programmed instructions as a series of holes punched in the tape, the plastic tape carried the instructions as a series of magnetic dots. The plastic tape was much stronger than the paper tape, which solved the problem of frequent tearing and breakage. However, it still left two other problems.The most important of these was that it was difficult or impossible to change the instructions entered on the tape. To made even the most minor adjustments in a program of instructions, it was necessary to interrupt machining operations and make a new tape. It was also still necessary to run the tape through the reader as many times as there were parts to be produced. Fortunately, computer technology became a reality and soon solved the problems of NC associated with punched paper and plastic tape.The development of a concept known as direct numerical control (DNC) solved the paper and plastic tape problems associated with numerical control by simply eliminating tape as the medium for carrying the programmed instructions. In direct numerical control, machine tools are tied, via a data transmission link, to a host computer. Programs for operating the machine tools are stored in the host computer and fed to the machine tool an needed via the data transmission linkage. Direct numerical control represented a major step forward over punched tape and plastic tape. However, it is subject to the same limitations as all technologies that depend on a host computer. When the host computer goes down, the machine tools also experience downtime. This problem led to the development of computer numerical control.3 TurningThe engine lathe, one of the oldest metal removal machines, has a number of useful and highly desirable attributes. Today these lathes are used primarily in small shops where smaller quantities rather than large production runs are encountered.The engine lathe has been replaced in today’s production shops by a wide variety of automatic lathes such as automatic of single-point tooling for maximum metal removal, and the use of form tools for finish on a par with the fastest processing equipment on the scene today.Tolerances for the engine lathe depend primarily on the skill of the operator. The design engineer must be careful in using tolerances of an experimental part that has been produced on the engine lathe by a skilled operator. In redesigning an experimental part for production, economical tolerances should be used.Turret Lathes Production machining equipment must be evaluated now, more than ever before, this criterion for establishing the production qualification of a specific method, the turret lathe merits a high rating.In designing for low quantities such as 100 or 200 parts, it is most economical to use the turret lathe. In achieving the optimum tolerances possible on the turrets lathe, the designer should strive for a minimum of operations.Automatic Screw Machines Generally, automatic screw machines fall into several categories; single-spindle automatics, multiple-spindle automatics and automatic chucking machines. Originally designed for rapid, automatic production of screws and similar threaded parts, the automatic screw machine has long since exceeded the confines of this narrow field, and today plays a vital role in the mass production of a variety of precision parts. Quantities play an important part in the economy of the parts machined on the automatic screw machine. Quantities less than on the automatic screw machine. The cost of the parts machined can be reduced if the minimum economical lot size is calculated and the proper machine is selected for these quantities.Automatic Tracer Lathes Since surface roughness depends greatly on material turned, tooling , and feeds and speeds employed, minimum tolerances that can be held on automatic tracer lathes are not necessarily the most economical tolerances.In some cases, tolerances of 0.05mm are held in continuous production using but one cut . groove width can be held to 0.125mm on some parts. Bores and single-point finishes can be held to 0.0125mm. On high-production runs where maximum output is desirable, a minimum tolerance of 0.125mm is economical on both diameter and length of turn.车床车床主要是为了进行车外圆、车端面和镗孔等项工作而设计的机床。

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外文资料Machine tool numerical control reformsFirst, CNC systems and the development trend of history1946 birth of the world's first electronic computer, which shows that human beings created to enhance and replace some of the mental work tools. It and human agriculture, industrial society in the creation of those who merely increase compared to manual tools, from a qualitative leap for mankind's entry into the information society laid the foundation. Six years later, in 1952, computer technology applied to the machine in the United States was born first CNC machine tools. Since then, the traditional machine produced a qualitative change. Nearly half a century since the CNC system has experienced two phases and six generations of development.1.1, Numerical Control (NC) phase (1952 to 1970)Early computer's computational speed low and the prevailing scientific computing and data processing is not affected, but can not meet the requirements of real-time control machine. People have to use digital logic circuit "tied" into a single machine as a dedicated computer numerical control system, known as the hardware connection NC (HARD-WIRED NC), called the Numerical Control (NC). With the development of components of this phase after three generations, that is, in 1952 the first generation - tube; 1959 of the second generation - transistor; 1965 of the third generation - small-scale integrated circuits.1.2, Computer Numerical Control (CNC) phase (1970 to present)To 1970, GM has been a small computer and mass-produced. So it transplant system as the core component of NC, have entered a Computer Numerical Control (CNC) stage (in front of the computer should be "universal" word omitted). To 1971, the United States INTEL company in the world will be the first time the two most core computer components - computing and controller, a large-scale integrated circuit technology integration in a chip, called the microprocessor (MICROPROCESSOR) , also known as the central processing unit (CPU).1974 microprocessor to be used in CNC system. This is because the function of the computer is too small to control a machine tool capacity affluent (the time has been used to control more than one machine, called Group Control), as a reasonable economic use of the microprocessor. Minicomputer reliability and then not ideal. Early microprocessor speed and functionality while still not high enough, but can be adopted to solve the multi-processor architecture. As microprocessor core is a general computer components, it is still known as the CNC.By 1990, PC machines (personal computers, domestic habits that computer) performance has been developed to a high stage, as a CNC system to meet the requirements of the core components. NC system based on PC has now entered the stage.In short, CNC has also experienced a stage three generations. That is, in 1970's fourth generation - small computer; 1974 of the fifth generation - microprocessors and the sixth-generation 1990 - Based on the PC (called PC-BASED abroad).Also pointed out that, although the foreign computer has been renamed NC (CNC), but China still customary said Numerical Control (NC). Therefore, we stress the day-to-day "NC", in essence, is that "computer numerically controlled."1.3, the trend of future development of NC1.3.1 continue to open, the sixth generation of PC-based developmentBased on the PC with the open, low-cost, high reliability, rich in resources such as hardware and software features, and more CNC system manufacturers will embark on this path. At least it used PC as a front-end machine, to deal with the human-machine interface, programming, networking and communications problems, the former NC Some systems have the mandate. PC machine with the friendly interface, will be universal to all CNC system. Remote communications, remote diagnostics and maintenance will be more widespread.1.3.2 high-speed and high-precision DevelopmentThis is to adapt to high-speed and high-precision machine tools to the needs of the development direction.1.3.3 intelligent direction to the developmentWith artificial intelligence in the computer field infiltration and the continuing development of the intelligent numerical control system will be continuously improved.(1)adaptive control technologyCNC system can detect some important information in the process, and automatically adjust system parameters to improve the system running state purposes.(2)the introduction of expert guidance processing systemthe experience of skilled workers and experts, processing and the general rules of law of special deposit system, the process parameters to the database as the foundation, and establish artificial intelligence expert system.(3)introduction of Fault Diagnosis Expert System(4)intelligent digital servo drivesAutomatic Identification can load, and automatically adjust parameters to get the best drive system operation.Second, CNC of the need for transformation2.1, microscopic view of the necessity ofFrom the micro perspective, CNC machine tools than traditional machines have the following prominent superiority, and these advantages are from the NC system includes computer power.2.1.1 can be processed by conventional machining is not the curve, surface and other complex partsBecause computers are superb computing power can be accurately calculated instantaneous each coordinate axis movement exercise should be instantaneous, it can compound into complex curves and surfaces.2.1.2 automated processing can be achieved, but also flexible automation to increase machine efficiency than traditional 3 to 7 times.Because computers are memory and storage capacity, can be imported and stored procedures remember down, and then click procedural requirements to implement theorder automatically to achieve automation. CNC machine tool as a replacement procedures, we can achieve another work piece machining automation, so that single pieces and small batch production can be automated, it has been called "flexible automation."2.1.3 high precision machining parts, the size dispersion of small, easy to assemble, no longer needed "repair."2.1.4 processes can be realized more focused, in part to reduce the frequent removal machine.2.1.5 have automatic alarm, automatic control, automatic compensation, and other self-regulatory functions, thus achieving long unattended processing.2.1.6 derived from the benefits of more than five.Such as: reducing the labor intensity of the workers, save the labor force (one can look after more than one machine), a decrease of tooling, shorten Trial Production of a new product cycle and the production cycle, the market demand for quick response, and so on.These advantages are our predecessors did not expect, is a very major breakthrough. In addition, CNC machine tools or the FMC (Flexible Manufacturing Cell), FMS (flexible manufacturing system) and CIMS (Computer Integrated Manufacturing System), and other enterprises, the basis of information transformation. NC manufacturing automation technology has become the core technology and basic technology.2.2, the macro view of the necessityFrom a macro perspective, the military industrial developed countries, the machinery industry, in the late 1970s, early 1980s, has begun a large-scale application of CNC machine tools. Its essence is the use of information technology on the traditional industries (including the military, the Machinery Industry) for technological transformation. In addition to the manufacturing process used in CNC machine tools, FMC, FMS, but also included in the product development in the implementation of CAD, CAE, CAM, virtual manufacturing and production management in the implementation of the MIS (Management Information System), CIMS, and so on. And the products that they produce an increase in information technology, including artificial intelligence and other content. As the use of information technology to foreign forces, the depth of Machinery Industry (referred to as information technology), and ultimately makes their products in the international military and civilian products on the market competitiveness of much stronger. And we in the information technology to transform traditional industries than about 20 years behind developed countries. Such as possession of machine tools in China, the proportion of CNC machine tools (CNC rate) in 1995 to only 1.9 percent, while Japan in 1994 reached 20.8 percent, every year a large number of imports of mechanical and electrical products. This also explains the macro CNC transformation of the need. Third,the choice of NC SystemNC system are the three major types of transformation, in accordance with specific circumstances Choose.3.1, stepper motor drive the open-loop systemThe servo drive system is stepper motor, stepper motor power, such as electro-hydraulic pulse motor. NC system by sending commands to the progress of pulse, the drive control and power amplifier circuit, the stepper motor rotate through the gears with ball screw drive of the implementation of parts. As long as control commands the number of pulses, frequency and electricity sequence can control the implementation of parts of the displacement movement, speed and direction of movement. Such a system does not require the test will be the actual position and velocity feedback to the input, so called open-loop system, the system accuracy of the displacement in the major decisions of the stepper motor angular displacement accuracy, transmission gear and other components of the leads crew pitch accuracy, the accuracy of the lower displacement. The system is simple, convenient debugging maintenance, reliable, low cost, easy modification success.3.2, or asynchronous motor DC Motor Drive, grating feedback loop measurement NC systemAnd the open-loop system is the difference between a system: from the grating, such as position sensors for simultaneous detection device measured the actual position feedback signals, at any time and to compare the value will be the difference between the two enlarge and change, driven implementing agencies , given the speed of elimination of bias towards the direction of movement, until a given position feedback and the actual location of the margin of zero. Feed the closed-loop system in the structure than to the open-loop system into the complex, high-cost, strict requirements on the environment at room temperature. Design and debugging difficult than open-loop system. However, can be compared to the open-loop system into higher accuracy, faster speed, greater power drive characteristic indicators. Under the technological requirements and decide whether or not to adopt this system.3.3, AC / DC servo motor drive, the semi-encoder feedback loop NC systemSemi-closed-loop system detection devices installed in the middle of transmission, the implementation of indirect measurement components position. It can only be part of the internal loop compensation system components of the error and, therefore, it compared the accuracy of the closed-loop system of low accuracy, but its structure and debug than simple closed-loop system. Will be in the angular displacement detection devices and speed detection devices and make a servo motor when there was no need to consider the overall position of the installation of detection devices.NC system for the current production companies more manufacturers, such as the famous German company SIEMENS, Japan FANUC companies; Everest domestic companies such as China, Beijing Aerospace CNC System Corporation, Shenyang and the central high-grade companies NC National Engineering Research Center.NC selection system is based mainly CNC machine modified to achieve the various precision, motor-driven power and user requirements.Fourth, the transformation of NC modification of the main mechanical componentsA new CNC machine tools in the design to achieve: a high static and dynamic stiffness of movement of the friction coefficient between small, transmission withoutclearance; big power; easy operation and maintenance. CNC transformation should be possible to achieve the above requirements. NC devices that can not be connected together with the general machine tools to reach the requirements of the NC machine tool, should also be major components corresponding to the transformation of up to a certain design requirements can be anticipated adaptation.4.1, sliding GuidewayOn the NC lathe, in addition to a general guide lathes and precision of sexual orientation, but also a good Naimaca, wear characteristics, and reduce the frictional resistance to the death zone. At the same time there must be enough stiffness to reduce rail deformation on the impact of machining accuracy, a reasonable guide protection and lubrication.4.2, deputy GearGeneral Machine concentrated in the main gear box and gearbox in the spindle. In order to ensure transmission accuracy, the use of CNC machine tool accuracy of gear higher grades than the general machine tools. In the structure must be able to achieve seamless transmission, thus transforming, machine main gear must meet the requirements of CNC machine tools, in order to ensure accuracy machining.4.3, and the ball screw sliding leadscrewScrew-drive directly related to the transmission chain accuracy. Screw selection depends largely on the accuracy of the processing of requests and drag torque requirements. Accuracy is the main requirement of processing may be sliding Screw, but should check the leadscrew wear, such as pitch and pitch error accumulated error and match Nut Gap. Sliding leadscrew general should not be less than six, the nut is too large gap replacement nut. The use of a sliding leadscrew relatively lower prices of ball screw, but it is difficult to meet the high precision machining.Ball screw friction losses small, high efficiency, the transmission efficiency of more than 90% of high accuracy, long life; starting torque and the torque of close campaigns, starting torque motor can be reduced. So to meet high precision machining requirements.4.4, securityEfficiency must be security as the prerequisite. Machine transformation in the light of the actual situation, we should take corresponding measures must not be ignored. Ball screw is sophisticated components, work to prevent dust particular chip and hard sand into the raceway. Screw in the vertical can also increase overall plate shields. And the extension units at both ends of the sliding contact surface Guide to seal well, absolutely rigid Coarse prevent the entry of foreign matter sliding surface damage Guide.Fifth, several examples of NC1, use of X53 milling SIEMENS 810M1998, the company invested 200,000 yuan, with Germany's Siemens 810 M CNC system, 611 A AC servo drive system for the company's X53 as a model of the milling machine for X, Y, Z three-axis NC transformation of the original reservation Spindle and cooling systems; transformation of the three-axis machine used in the roller screw and gear drive mechanism. Transformation of the entire work includes mechanicaldesign, electrical design, PLC and the establishment of procedures for debugging, machine overhaul and, finally, the components are installed and debug. Milling After the transformation, processing effective itinerary X / Y / Z-axis respectively 880/270/280 mm; maximum speed X / Y / Z-axis respectively 5000/1500/800 mm / min; manual speed X / Y / Z-axis respectively 3000/1000/500 mm / min; machining accuracy of ± 0.001mm. Coordinate machine can be linked to complete all kinds of complex curves and surfaces processing.2, and Step by GSK980T driven system of the C6140 Lathe1999, the company invested 80,000 yuan, a Guangzhou NC plant production GSK980T NC system, DY3 hybrid stepping drive unit for the company's C6140 longer a lathe X and Z axes to transform the two retention The main axis of the original system and the cooling system; transformation of the two-axis machine used in the roller screw and belt drive mechanism. Transformation of the entire work includes mechanical design, electrical design, machine overhaul and the components are installed and debug. Lathe After the transformation, processing effective itinerary X / Z-axis respectively 390/1400 mm; maximum speed X / Z-axis respectively 1200/3000 mm / min; manual speed of 400 mm / min; manual for the rapid X / Z-axis respectively for the 1200/3000 mm / min; machine smallest mobile units of 0.001 mm.3, and GSK980T with AC servo drive system of the C6140 Lathe2000, NC plant in Guangzhou with production GSK980T NC system, DA98 AC servo unit and 4-position automatic tool carrier of a motor factory lathe C6140-X, Z two-axis NC transformation of the original reservation the spindle and cooling systems; transformation of the two-axis machine used in the roller screw and belt drive mechanism. Transformation of the entire work includes mechanical design, electrical design, machine overhaul and the components are installed and debug. Lathe After the transformation, processing effective itinerary X / Z-axis respectively 390/730 mm; maximum speed X / Z-axis respectively 1200/3000 mm / min; manual speed of 400 mm / min; manual for the rapid X / Z-axis respectively for the 1200/3000 mm / min; machine smallest mobile units of 0.001 mm.4, use of X53 milling SIEMENS 802S2000, the company invested 120,000 yuan, with Germany's Siemens 802 S CNC system, stepping drive system for the company's another model of the X53 milling machine for X, Y, Z three-axis NC transformation of the original reservation Spindle and cooling systems; transformation of the three-axis machine used in the roller screw and gear drive mechanism. Transformation of the entire work includes mechanical design, electrical design, machine overhaul and, finally, the components are installed and debugged . Milling After the transformation, processing effective itinerary X / Y / Z-axis respectively 630/240/280mm; maximum speed X / Y / Z-axis respectively 3000/1000/600mm / min; manual feed rate X / Y / Z-axis respectively 2000/800/500mm / min; smallest mobile units of 0.001mm.中文翻译机床数控改造一、数控系统发展简史及趋势1946年诞生了世界上第一台电子计算机,这表明人类创造了可增强和部分代替脑力劳动的工具。

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