外文翻译原文-数控技术
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)。
数控加工技术概述外文翻译、中英文翻译、外文文献翻译
原文:The digital control process technology is summarized1. digital control programming reaches such developmentThe digital control programming is the segment that be able to obviously bring into play the beneficial result in at the moment CAD/CAPP/CAM's system the most most , such is living to achieve to design the process automation and raise process accuracy and processes the quality and cuts down the product development cycle and so on the respect is brining into play the significant action . Being living possess the greats quantity applications such as aviation industry and auto industry and so on territorys . Since giving birth to the intense demand of practice , wide-ranging research has wholly been carried on to the digital control programming technique in the home and abroad , and acquires the plentiful and substantial fruit . The next reaches such to the digital control programming and develops to act as some to introduce .1.1 basic concept of digital control programmingThe digital control programming is through the spare parts drawings up the full process that obtains the digital control processing program . Its main mission is that the sword spot ( Cutterlocationpoint abbreviate CL's spot ) in the sword is processed away in the calculation .The point of intersection that sword the spot was oridinarily get to the cutting tool axial line against the cutting tool face still will be give out the sword shaft vector in much processs1.2 digital control programming technique development surveyMIT designed one kind of special language that is used in the inflexible spare parts digital control processing program establishments to the program problem in order to resolve in the digital control process , andis called APT ( AutomaticallyProgrammedTool ) in the 50's .Well-developed editions such as after APT time and again develops , takeed shape such as APTII and APTIII ( the stereoscopic cutting action is employd ) and APT ( the algorithm improves , add much coordinates surface processes the programming meritorous service capacity ) and APTAC ( Advancedcontouring ) ( add cuts the database administration system ) and APT/SS ( SculpturedSurface ) ( add engraves the camber processes the programming meritorous service capacity ) and so on .Adoping APT language drawing up digital control order to have easy the refineing of order , and gos away the strongs point such as sword control is agile and so on , and causes the digital control process the programming , and moves upward up yet possess much not suitable points to geometry element .APT through " assemble language " grade to the machine tool order : Adoping language definition spare parts geometry form shape , and is difficult to depict complex geometry form shape , and lack audio-visual quality of geometry ;The certification measure that the figure audio-visual that is short of to spare parts form shape and the cutting tool movement locus displays and the cutting tool locus ;Being difficult to effectively join with CAD's data bank and CAPP's system ;Not to act as easily up the high automation , the integrationizationIn view of the APT's language defect , in 1978 , France attained the system that the large rope airplane corporation starts development gathers assemble three dimensions design , analysis and NC's process integration , and is called in the interest of CATIA .Having ariseed alikely the systems such as EUCLID and NPU/GNCP and so on soon afterwards very quickly , the geometry moldswholly valid settlements of these systems and the spare parts geometry form shape display is designed mutually and mends generates the cutting tool locus , and the problems such as the imitation to go away the sword process displays and certification and so on promoteed CAD and CAM developing to the integration orientation . The approximately idea that system ( CIMS ) and parallel project ( CE ) was manufacture in the calculating machine integration take shape up the 80's gradually on the base that the CAD/CAM's integration being living is approximately attend school . At the moment , and the necessaries that CE developed in order to adapt to CIMS , the digital control programming system to integrationization and intelligentization the development .Being living the integration respect , with the development accords with the STEP ( StandardfortheExchangeofProductModelData ) criterion parameterization feature moldmaking and systematically gives priority to , having carried on the highly effective work of greats quantity at the moment is the home and abroad development heatpointBeing living the intelligentization respect , the work has start only a short while ago , and still awaits that we leave hard2、NCs' cutting tool locus generates the method study developing actualityDigital control programming core work is generateing the cutting tool locus , afterwards by such scattered one-tenth sword spot , places that the handle comes into being the digital control processing program afterwards viaing .The next cutting tool locus comes into being the means and actes as some and introduce2.1 baseding on a little and string , surface and part of the body NC's sword track formation meansCAD's technique moves through the two dimension mapping , andudergo the three dimensions wires frame and camber and the solid modelling generation , now the parameterization feature reacing is always moldded .Is living two dimension mapping together with three dimensions wires frame phase , in case the opening processes , the rough sketch is processed the digital control process is main with spot and string act as drive target , the plane area process and so on .This kind of level that personnel staff was requireed manipulating in the process is taller , complex mutually .Being living camber and the solid modelling generation , entity process had ariseed to based on .The entity process target is an entity ( oridinarily blendes for CSG and BREP express ) , its ( moreover , intersects , falls short of to operate ) but get yield through some fundamental parts of the body habitually after the set operation .The entity is processed not merely usable rough machining and semi precision work to the spare parts , and the great area cuts Yu Liang , and the effectiveness is processed in the raise , but also usable research together with development to digital control baseding on the feature programming system , is the feature process baseEntity process oridinarily possess entity rough sketch process and the entity area and processes two kinds .The entity process realization means slices law ( SLICE ) in the interest of the straturm , in immediate future slices by the process entity in the way of one series of level , afterwards to obtains the intersection comes into being the isometry string dos worthwhile the sword the going away locus .The original slave system needs the angle depart , the digital control process that the ACIS's geometry moldmaking being living achieved thiskind to based on a little on the terrace and the string and surface and entity Feature NC's sword track formation means 2.2 baseding onThe parameterization feature molds to possess the specified development particular period , yet baseds on that feature cutting tool locus formation means research starts only a short while ago .The feature processes to cause digital control programming personnel staff to be out to let drop the step geometry message to those ( in case : Spot , string , surface and entity ) manipulate , but transforing to carry on the digital control programming in the interest of directly to accords with the feature that engineers and technicians are used to , and liftd the programming effectiveness enormouslyW.R.Mail and A.J.Mcleod are living in their research to give out one to based on feature NC's code generating sub system , and this systematic work rule is : Spare parts every one process wholly may be regarded as to adjust to make up the total that the spare parts form shape feature group processed .In immediate future the queen completees spare parts process is not processed that to the feature adjusting entirely form the shape in that way either form shape feature component .But each form shape feature either form shape feature series NC's code may generate voluntarily .The system opened up at the moment merely is applicable to 2.5D's spare parts processThe LeeandChang opened up one kind of raised liberal camber feature cutting tool locus of means autogeneration in the way of fictitious border system .This systematic work rule is : Being living to inlay inner place the raised liberal camber into one the minimal long and square , so raised liberal camber feature is transformd into the hollow feature .Minimal the long and square incorporation against the end product pattern constituteed to be called one kind of indirect produce pattern on the fictitious pattern .That the cutting tool locus formation means separates into completees three paces : ( 1 ) and the cutting action polyhedron feature ;( 2 ) and cuts the liberal camber feature ;( 3 ) and the cutting action intersects the featureJongYunJung researcies baseds on the non- cutting action cutting tool locus formation problem of feature .The article process baseding on the feature locus separates into rough sketch process and processes two types with the inside area , and the definition this two types of process cutting action orientations , attains the aim that the entirety optimizes the cutting tool locus by means of decreasing the cutting action cutting tool locus .Type who talked about these fundamental features gos away sword way and cutting tool selection and process order and so on to main being aimed at of article some kinds of fundamental features ( hollow inner place Kong and step , trough ) , and averting repeatedly going away the sword by means of IP ( InterProgramming ) technique , with the non- cutting action cutting tool locus of optimization .Besides JongYunJong still is living , and his doctor in 1991 researcied tabrication feature extraction and baseds on feature cutting tool and the cutting tool way in the dissertationThe feature process base is an entity process , and surely of course also may think the entity process being more high-quality .Yet feature process distinct entity process , and entity process possess it oneself the limitations .Feature process chiefly possess below difference against entity process :Through approximately attends school says that the feature is the meritorous service capacity key element to make up the spare parts , and the operation that accords with engineers and technicians is used to , by engineers and technicians are know intimately ;The entity is the geometry target on low straturm , and is a geometric object that obtains after a series of Booleans calculation , and does not have whatever meritorous service capacity semantic information ;It frequently is adjusting the once only process of entire spare parts ( entity ) that the entity is processed .Yet in reality the spare parts is not very much probably merely once processed through in the way of the sword , frequently will go through a series of workmans of rough machining and semi precision work and precision work and so on stage , the place of spare parts difference oridinarily will be employd the difference cutting tool and process ;Now and then not only the spare parts will be employd up turning , but also employ up mill .Hence entity process is chiefly used spare parts rough machining and semi precision work .But but the feature on processing through essentially resolved the above-mentioned issue ;Feature process havees even more intellect .May regulate some kinds of settled admittedly process meanss as to the specially designated feature , particularly those have been living , and STEP's criterion the person who regulates the feature still more is such in this way .In case we wholly draw up the specially designated process means to all standards feature , it is you can imagine that spare parts that in thatway sufficiently succeed through the standard feature to those are processed such convenient quality .In case CAPP systematically be able to supply the relevant technology feature , NCP's system may decrease inputing mutually , and havees even more intellect enormously in that way .But these entity process can not achievedFeature process is favour of achieving through comprehensive integration of CAD , CAPP , NCP and CNC's system , and achieves the two-way going from place to place of message , in the interest of CIMS and even parallel project ( CE ) are settleed the well base ;It be helpless that but the entity is processed to theseNC's sword track formation means 2.3 being on active service in several main CAD/CAM's systems is analysedActive duty CAM constitutes reaching the main meritorous service capacityThat at the moment comparatively more mature CAM's system is main with two kinds of shapes achieves CAD/CAM's system integration : Integration CAD/CAM's system ( in case : UGII , Euclid and Pro/ENGINEERs and so on ) and independent relatively CAM's system ( in case : Mastercam and Surfcams and so on ) . Unitary less than the former data format is directly gaind the produce geometric model through CAD's system , but the latter is main gains the produce geometric model by means of the neutral papers through else CAD's systems . However , no matter is what the CAM's system growed the shape , wholly consising of five modules , in immediate future mutually technology parameter input module and cutting tool locus formation module and cutting tool locus compiler module and three dimensions process that dynamic imitation module and afterwards places the processing module . Next merely some famous CAD/CAM's system NC's process meanss are holied discussions .UGII's process means is analysedOridinarily think that UGII is the best in trade circle , and havees representativeness digital control software most .That such havees the distinguishing feature most is the cutting tool locus formation means that such meritorous service capacity is powerful .Consists of turning , milling and string cuts and so on the consummate process means .In it milling chiefly possess the below meritorous service capacity :And PointtoPoint: Completeing the different openings processesAnd PanarMill: Plane is milled .Consising of that the one-way walkes surely , the two-way row are slice , and the hoop is slice along with rough sketch process to await And FixedContour: Admittedly much projectionss are areed processed stably .Dominateeing on being living on the single camber either much camber the removing of cutting tool in the way of the projection means , and that the control cutting tool is removed may be the cutting tool locus that has generateed , a series of either suite stringAnd VariableContour: Variable projection is processedAnd Parameterline: Await that the parameter string is processed .The successive process of single camber either much camber may be adjustAnd ZigZagSurface: Cutting out processAnd RoughtoDepth: Rough machining .The depth is reachd assigning in the rough machining by Mao PiAnd CavityMill: The many stages depth mould cavity processes .Rough machining that particularly is applicable to the male contact with the hollow standardAnd SequentialSurface: The camber occuies simultaneously the workman .In accordance the spare parts and guides that and the thinking of check adjust the removing suppling the largesttest degree control of cutting toolEDSUnigraphics still consists of greats quantity else the respects meritorous service capacitys , and did not enumerate one by one here STRATA's process means is analysedSTRATA is a digital control programming system development environment , and it is establishing ACIS's geometry model building terrace onIt supplys two kinds of programming development environments in the interest of consumer , in immediate future NC's command language interface and the NC's operation C++ storehouse . It may back three to mill , and turning and string cut NC and process , and may back wire frame , camber and the entity geometry model building . Such NC's cutting tool locus formation means is baseding on the physical model . STRATA is baseded on , and what supplys the process means in entity NC's cutting tool locus formation type storehouse consists of : ProfileToolpath: Rough sketch processAreaClearToolpath: The area on plane processesSolidProfileToolpath: The entity rough sketch is processedSolidAreaClearToolpath: The area on entity plane processesSolidFaceToolPath: The entity face processesSolidSliceToolPath: The entity severs process on planeLanguagebasedToolpath: Baseding on , language cutting tool locus generatesElse CAD/CAM software , in case Euclid the person who awaits the NC's meritorous service capacity is each has his strong point , yet suchfundamental substance is almost alike , the not natural difference .2.4 main problem of systematic sword track formation means of active duty CAMIn accordance tradition CAD/CAM's system and CNC's system work means , CAM's system is with directly either the indirect means gains the produce geometry data model through CAD's system ( by means of neutral papers ) . CAM's system is with spot , string , surface in the three dimensions geometrics model and either the entity is the drive target , the cutting tool locus is processed in the formation , and afterwards the shape with the cutting tool locating file viaes the handle is placed , with the NC's code shape supplys to CNC's machine tool , the some respects problems under being living in entire CAD/CAM and the CNC's system operation process to be :CAM systematically can only gain produce low tier of geometry message through CAD's system , and can not seize voluntarily meritorous service capacity and the semantic information of produce geometry shape information and produce higher level .Hence manufacturing engineering master that entire CAM's process have to be living is very experience haves a hand in secondly , and completees mutually by means of the figure .In case : Manufacturing engineering master .The entire system automation degree is leted dropBeing living in the CAM's system generation cutting tool locus , equal also merely embodying low straturm geometry message ( right line and arc geometry locating information ) , along with the a little process control information ( as moving forward ) to rate , main shaft rotation speed and trading sword and so on .Hence , can not obtain the process technology parameter that haves something to do with against generateing the cutting tool locus yetThe produce data between CAM's system every module are not unitied , and the independence is opposite to each other to every module .For instance the cutting tool locating file is merely keep the minutes the cutting tool locus and is not keep the minutes the relevant process technology parameter , the dynamic imitation of three dimensions merely keeps the minutes that the cutting tool locus interference against runs into , but keep the minutes interference and process target and correlation process technology parameter that runs into happen against suchThe CAM systematically is an independence system .Not thering is the unitary produce data model between CAD's system together with the CAM's system , even if being the integrated CAD/CAM's system of integration in , one-way and unity is enjoyed also being only to message in all . CAM systematically can not sufficiently comprehend and complete message utilizing CAD's system to have something to do with the produce , feature message that especially haves something to do with against process , equal CAD's system can not gain the process data message that CAM systematically come into being yet . This is give parallel project implementation to bring the hardship3、digitals control techniques of simulation3.1 calculating machine imitation approximately idea and applicationThe angle through the project is see , and the imitation is the system by means of the test to the system model leave to research in the existing either design .Analysing the complex dynamic target , the imitation is one kind of valid means , may decrease the hazard , cuts down design and manufactures cycle , and practise thrift the investment .Calculating machine imitation is draing support from the calculatingmachine , and utilizes the system model to adjust actually systematically testing the process which researcied .It is swiftly developed in the wake of the calculating machine technique development , and is living in the imitation to passess the more and more significant position .Three foundation maneuveies between the key element that the calculating machine imitation process may be notify by means of the picture 1 are depictd :The model building maneuver is by means of viewing either examination to the actual system , and is living to over look the less important element to reach on the base that examine the variable , and the means in the way of physics either mathematics is depictd , thereby obtains the similar pattern of actual system simplification .The meritorous service with the actual system of the pattern here be able to together with between the parameter ought to have similarity and homologous qualityThe imitation pattern is the mathematical model to the system ( simplifying the pattern ) carries on the specified algorithm handle , and causes such become the appropriate shape ( in case turns into iterative operation pattern by the numerical integration ) afterwards , yet becomes " computation module computational mode " that be able to be receiveed by the calculating machine .The imitation pattern is two simplification patterns to the actual systemThe imitation test is shall system imitation pattern be living the process rund in the calculating machine .The imitation is researching actual system one kind of technique by means of the test , may clarify systematically immanent structure variable and the ambient condition effect by means of the technique of simulationCalculating machine technique of simulation main expressing of development tendency be living two respects : Application territory enlargement and imitation calculating machine intelligentization .The calculating machine technique of simulation not merely is living tradition project technique territory ( respects such as aviation , spaceflight and chemical industry and so on ) subsequent development , but also broadens up community economy and living beings and so on much non- project territorys , moreover , technique such as parallel processing , artificial intelligence , knowledge base and expert system and so on the development is affecing the imitation calculating machine development Digital control process imitation utilizes the calculating machine imitation practice process , being the forceful means to verify digital control processing program dependability and the calculation cutting action process , in order to decrease work attempies surely , and lifts production efficiency3.2 digital control technique of simulation research present situationThe APT process spare parts are completeed near the digital control order program control .In the interest of right quality to guarrantee the digital control order , guard against in process to intervene happenning , and is living in the actual manufacture , and constantly adopts attempting the anxious means to examine with what runs into .Yet this kind of means requiring a lot of labor expense is anticipateed , the cost expansively causes the manufacturing cost move upward , addd produce process time and production cycle .Adoping once more the locus to display the law afterwards , in immediate future in order to mark needle either pencil or writing brush replace the cutting tool , with colouring plank either paper replaces the work imitation cutting tool movement locus two dimension figure ( alsomay display the two dimension semi process locus ) , possess the considerably great limitations .Three dimension and the many-dimensionss as to the work are processed , the cutting action locus that the inspection that the stuff that also possess use easily to cut replaces the work ( in case , paraffin wax , lumber , midified resin and plastic material and so on ) comes is processed .Yet APT and the process field is very important occupied in the attempt .For this reason , people are living always to research replace gradually attempting the anxious calculating machine emulation mode , and is living to attempt to slice that the respects such as environment modeling and imitation calculation and graphic display and so on acquire the significant progress , and develops to raise pattern accurateness and imitation calculation real timeization and improvement real feeling of graphic display and so on orientations at the momentThrough attempies the pattern distinguishing feature sliceeing the environment seeing , NC's cutting action process imitation branch geometry imitation and mechanics imitation at the moment two respects .Geometry imitation is not consider that cutting action parameter and cutting force reach else the physics elements effects , the imitation cutting tool work geometric object movement , and with right quality of certification NC's order .The problem such as it may decrease either remove as a result of the machine tool injury that the program error causes and clamping apparatus damage either the cutting tool rolls over to snap and the spare parts are reported something as worthless and so on ;May decrease moreover through the product design up time manufacturing , and cut down the manufacturing cost .Cutting action process mechanics imitation pertains to the physics imitation category , and its dynamic mechanics property by means of the imitation cutting action process is forecast that the cutting tool breakage and cutting tool vibration and control cuts the parameter , thereby attains to optimize the cutting action process aimThe geometry technique of simulation development is in the wake of geometry model building technique development but development , and consists of that quality graphic display and the ration is intervened verifying two respects .At the moment the means in common use possess the immediate solid modelling law , and the means of figure image space baseding on is requestted the intersection law with the scattered vector3.3 immediate solid modelling lawThis kind of enveloping solid that the means is the work part of the body against the cutting tool movement takes shape is underway that the entity Boolean falls short of operating , and the work part of the body three dimensions patterns are continuously replaceed in the wake of the cutting action processSungurtekin and Velcker opened up a miller simulation system .The three dimensions patterns that ought to systematically adopt CSG's law to keep the minutes Mao Pi utilize some fundamental primitives like cuboid , the cylindrical body and taper part of the body , and the set operation , particularly operating , the area by Mao Pi and a series of cutting tool scannings is keep the minutes , afterwards usies the set difference and operates through Mao Pizhong's order take-offing the scanning area .Traverse when the so-called area by has sweep is cutting the cutting tool to move along some locuss area .Per length of Mao Pixing's shape that NC's code afterwards。
中英文文献翻译-加工中心数控技术
Reference: classification and their respective characteristics of nc machining center Press: chemical industry press; Version 1 (March 16, 2009)Author: Xu Heng, Duan XiaoxuMachining center is a typical set of high-tech machining equipment in one, itsdevelopmentrepresents a country'slevel of design andmanufacture greatlyimproved laborproductivity, reducelabor costs, improvedworking environmentand reduce the laborof workers strength.This movementthrough the differentprograms and thedesign of variouscomponents of qualitative analysis and comparison of vertical machining centers to determine the progress of education to drive the program are: fixed-bed body, spindle seat installed by installing the sliding seat rail bed , use rolling guide rail bed can beachieved to the movement into the Y direction. Precision CNC XY table by a two-way drive to complete the workpiece X, Y two directions into a movement; X, Y, Z three directions of movement are ball screw feed, driven by AC servo motor. Guides, ball screws with the corresponding lubrication, protection and other devices.Processing center ( English abbreviate is CNC called Computerized Numerical Control ): is the library with a knife and automatic tool changer of a highly automated multi function numerical control machine tool. In China, Hongkong, Taiwan and Guangdong generation also has many people call it the computer gongs.Workpiece in machining center by a clamping, digital control system can control the machine tool according to different process, automatic selection and replacement of tools, automatically change the spindle speed, feed rate and cutting tool relative to the workpiece movement track and other auxiliary functions, followed by the completion of several surface workpiece multiple processing procedures. And there are a variety of changing knife or blade selection function, thereby greatly improving the production efficiency.Machining center CNC machine tool is provided with a computer numerical control system of machine tools, CNC system capable of processing procedures, control machine tools to complete a variety of actions. Compared with the general machine tools, CNC machine tools to complete the plane curve and space curve surface machining, the machining precision and the production efficiency is relatively high, so it has been widely applied.The composition of CNC machine toolsIn general, numerical control machine tool is composed of a mechanical part, a digital control computer, servo system, PC control part, hydraulic pressure drive system, cooling and lubrication and discharge device. CNC machine tool is controlled by a program, part of the programming work is the important part of NC machine tool. Servo system of CNC machine tool is driven in part, computer output control command is generated by the servo system coordinate movement. Ordinary vertical machining center with three servo motors to respectively drive workbench,longitudinal, transverse worktable, spindle box along the X direction, Y, Z to exercise. X, Y, Z are mutually vertical coordinate axis, so when the machine three coordinate linkage can machining space curved surface. And for the five axis linkage CNC machine, is a B axis and C axis. The Y axis of rotation of the shaft as the axis B, Z axis of rotation of the shaft as the C axis.The processing of CNC machine tools motionMachining by cutting the main movement and feed motor complete, control the main movement can be a reasonable speed, to control the feed can obtain all kinds of different machining surface. CNC machine tool coordinate motion is motion, for the three coordinate NC machine tool, the coordinates of the direction of movement is usually perpendicular to each other, whereby the respective along the Cartesian coordinates X, Y, Z axis positive and negative direction. How to control the moving coordinate system to complete different kinds of spatial curved surface processing is the main task of digital control. As we all know, in the three-dimensional Cartesian coordinates, space any point can be used X, Y, Z coordinate values to indicate, to a space curve can also use the three-dimensional coordinate function to express. How to control the axis of movement to finish machining of curved surface? Now to introduce it.Curved surface cutting tool moving trajectory and theoretic curves do not coincide, but an approximation line. Due to various interpolation formula is different, the approximation of the line are also different, usually has the following several calculation methods: point by point comparison method, integration method and time division method.The advantages, disadvantages of NC machine toolCNC machine tool has many advantages, it is developing very quickly, become the dominant machine machining.( 1) machining with NC machine tool can achieve good accuracy, stable processing qualityCNC machine tool transmission parts, particularly a ball screw with high precision. The assembly eliminates the transmission gap, and the use of improved stiffness measures, so the transmission precision is very high. Machine tool use rolling guide rail or bonded with the friction coefficient is small synthetic plastic, thus reducing the friction force, elimination of slow speed creeping. Loop, loop servo system, with high accuracy position detection device, and at any time to position error feedback to the computer, which can timely error correction. Thus the CNC machine tools to obtain high precision. CNC machine tools of all operations are performed by program control, if the control system is stable and reliable, it is very reliable, and the manual operation, numerical control machine tool without human interference, and stable processing quality.( 2) has a high production efficiencyIn the NC machine tool is usually not heavy grinding clamping type props, with hard surface coating, so the high cutting speed. Using a tool for cutting, machining center knife with a sufficient number of cutter, automatic tool change speed is very quick, air travel speed is in 15m/min above, some reached 240m/min, so the auxiliary time is short.Compared with the general machine tools, CNC machine tool production efficiency can be increased by 2~3 times, some can reach several tens of times.( 3) multiple functionsMany numerical control machine tool has many processing functions, on one machine can be boring, boring, milling, slot milling, milling plane cam curves and contours, and lettering.In addition to clampingsurface of thehexahedron fivesurface processing,sometimes also withthe coordinate planeangled plane processing. Installed in a card to complete a variety of processing, can be eliminated by the repeated clamping errors. Also reduces the measuring and clamping auxiliary time.( 4) in different parts of adaptabilityIn the same units of CNC machine tools can be adapted to different types and sizes of the parts processing, as long as the replacement of the processing procedures, can change the processing parts varieties.( 5) to complete the common machine tool can not complete the complex surface processingSome of the space curved surface, such as a screw surface, five coordinate NC machine tool processing, so that the performance is greatly improved; NC copying a broader range of applications, with repeated application, image processing function.( 6) CNC machine tools can greatly reduce the labor intensity of workers, and has higher economic benefit.Everything has its duality, CNC machine tools is not without drawbacks, mainly has the following several aspects:1) high price, a large investment.2) repair and operate more complicated requirements with high technical level and cultural level of the workers and staff in operation and repair repair. NC machine tool is the development of science and technology results. High technology products, certain requirements of high technology talent operation and repair, and if it is a weakness, still be inferior to saying it to people culture to improve the technology level of a promotion.CNC machine tool is applicable to many varieties, small batch production; the more complex shapes, high precision parts processing; frequent update of the products, the production cycle short processing; NC machine tool can be composed with automation workshop and factory automation ( FA ), the more is composed of flexible automation production line ( FML ), flexible manufacturing unit ( FMC ) and flexible manufacturing system ( FMS ).CNC machine tool classificationAt present, CNC machine too ls complete varieties, many specifications, but from different angles and in various principles of classification.According to the technological purpose classification( 1) metal cutting type NC machine tool of this kind of machine tool and the traditional general breed of machine tool, CNC lathes, CNC milling machine, CNC drilling machine, CNC grinding machines, CNC boring machine and machining center. Machining centers with automatic tool changer, installed in a card can be a variety of processes of CNC machine tools.( 2) metal molding CNC machines such as CNC bending machine, CNC bending machine, CNC turret press.( 3) NC machining and other types of CNC machines such as CNC wire cutting machine, CNC EDM machine, CNC laser cutting machine, CNC flame cutting machine.Vertical machining center: refers to the spindle axis and a worktable arranged vertically processing center, is mainly suitable for processing board type, disc type, mold and small housing complex parts. Vertical machining center can finish milling, boring, drilling, tapping and using thread cutting process. Vertical machining center is at least three two axis, the general can achieve three three axis. Some five axes, six axis control. Vertical machining center column height is limited, to a case-body-like workpiece processing to be reduced, this is a vertical machining center. But the vertical machining center the workpiece clamping, convenient location; cutting tool trajectory easy observation, convenient debugging program check measurement, can discover a problem in time, is shut down or modified; cooling condition easy to establish, cutting fluid can directly reach the tool and machining surface; a three coordinate axis and Cartesian coordinates anastomosis, intuitional sense and pattern from the perspective of consistent, chip easy removal and fall, to avoid scratching the processed surface. And the corresponding horizontal machining center, and has the advantages of simple structure, small occupied area, low price.Machining center is a under the control of the computer with automatic tool changing system can complete multiple process composite processing automationmachine tool, and a forward high speed, high precision, modularization, network and complex of the direction of development. The machining center is a typical set of high-tech in one of the mechanical processing equipment, its high production efficiency, good flexibility, the use of a machine and is easy to process the complex curve, surface features, has become the industry developed countries the main processing equipment and machinery industry. A national processing center has quantity, consumption and overall technical level and the national machinery industry manufacturing technology level is closely related to. China's processing center begins from 70 time, already had very great progress, but the technology, variety and quantity are not adapted to the economy of our country, the needs of technology development. Enter after twenty-first Century, Chinese processing center consumption with the military and civilian machinery industry large-scale technical reformation and rapid growth, such as the 2001 China machining center consumption was only 2662 (of which imports 2290 ), and the same year the United States, Japan and German machining center consumption respectively 11505, 6090 and 5291. By 2005, China processing center consumption soared to about 13200 ( estimates, machining center output data not released), which imports 10343. In 2005 the processing center consumption is 4.96 times that of 2001, year all amplitude is amounted to 49.2%, in one fell swoop over the United States, Japan, Germany and countries, to become the world most the country consumption processing center.According to the "machinist " magazine andother units of the survey,from nearly 600 copies onthe user's effectivequestionnaire results,machining centerapplication has beenthroughout the 26 industries, including automobiles, motorcycles and spare parts manufacturing industry accounted for 34%, aerospace and military industry accountedfor 24%, accounting for 18% of machine tool industry, the mold industry accounted for 15%, light industry machinery industry accounted for 9%. In these enterprises have the processing center, although the popular type of vertical and horizontal machining centers still accounted for the majority, but the multi-axis, high speed, large precision and other high-end machining centers also occupy a certain proportion, such as in a survey of nearly 600 users, with 5 axis machining center 24%. Description of Chinese consumption market of machining center although popular mid-range machine, but high-grade machine in consumption proportion is estimated that 15% to 20%. China's consumption of machining center most rely on imports ( 2005 imports accounted for more than 70% of consumption ), import an amount of $1297000000, ranking first in all kinds of machine tool imports, mainly from Japan, China, Taiwan, Germany and South Korea to import. The first half of 2006, China imported machining center 5511, amount 688000000 dollar, grow respectively compared to the same period 20% and 11%, still maintain two digit growth, China machining center market scale and growth space.The technological level of industrial equipment and modernization of the entire national economy determines the level and degree of modernization, numerical control technology and equipment is the development of new high-tech industry and cutting-edge industries ( such as information technology and industry, biological technology and industry of aviation, aerospace and other defense industry industries) of the enabling technology and the most basic equipment, Kyth once said, " the distinction between the economic times, what is not production which is how the production, what the production of labor manufacturing technology and equipment is the human production of the most basic means of production activities, and numerical control technology is today's advanced manufacturing technology and equipment, the core technology. This in order to enhance the level of manufacturing capacity and to increase the dynamic market, adapt to the widely used around the world NC manufacturing technology, in addition, the developed countries in the world the numerical control technology and numerical control equipment as the strategic materials of the country, not only take significant measures to develop its own digitaltechnology and its industry, but also in the "sophisticated " digital key technology and equipment to China's policy of closures and restrictions. In conclusion, develop energetically with numerical control technology as the core of the advanced manufacturing technology has become the world each developed countries to accelerate economic development, enhance comprehensive national strength and the national status of important ways.NC technology is the use of digital information on the mechanical movement and the work process control technology, numerical control equipment is based on CNC technology as the representative of the new technology to traditional industry and burgeoning manufacturing industry form the infiltration of electromechanical integration products, the so-called digital equipment, the technical scope covers many fields: ( 1) machinery manufacturing technology; ( 2) information processing, processing, transmission technology; ( 3) automatic control technology; ( 4) servo drive technology; sensor technology; ( 5) ( 6) software technology.The development tendency of CNC numerical control technology application is not only to the traditional manufacturing industry has brought a revolutionary change, make the manufacturing industry to become a symbol of industrialization, and, with the continuous development of NC technology and the expansion of application fields, beneficial to the people's livelihood he on some important industry ( IT, automobiles, light industry, medical and so on ) development plays a more and more important, because these industries needed equipment digital is a modern development trend.Numerical control technology in China started in 1958, nearly 50 years of the development process can be divided into 3 stages: the first stage is from 1958 to 1979, i.e. closed type development stage. At this stage, because foreign technology blockadeand our basic conditionsof development ofnumerical controltechnology is relativelyslow. The second stageis in the national " six five ", " seven five " and " eight five " during early restriction, namely technology introduction, digestion and absorption, preliminary build localization system stage. At this stage, because of reform and opening up the country, and the importance of research and development of environment and international environment improvement. Our country numerical control technology research and development as well as in the domestic products have made considerable progress. The third stage is in the national " eight five " and " Nine Five " of the late period, namely the implementation industrialization research, into the market competition stage. At this stage, China's domestic CNC equipment industry has made substantial progress. The "Nine Five " stage, domestic CNC machine tool 's 50% share of the domestic market with domestic NC system ( Universal ) also reached 10%. Looking at China's CNC technology development course of nearly 50 years, especially after the 4 5 years plan research, overall obtained the following results. Lay the CNC technology development foundation, basic knowledge of modern NC technique. China now has basically mastered from the NC system, servo drive, NC machine, special machines and accessories based technology. Most of these techniques have commercial development foundation, part of technology commercialization, industrialization. B. initially formed the industrial base of CNC, the research achievements and technology commercialization based on. To establish such as CNC, aerospace has a production capacity of the production plant of CNC system, CNC and a number of servo system and servo motor production plant, Beijing first machine tool plant, Ji'nan first machine tool plant of machine manufacturing plant. These factories basically formed our country numerical control industry base. C. established a CNC research, development, management personnel of the basic team. In the numerical control technology research and development and industrialization has made considerable progress, but we also should realise soberly, our high-end CNC technology research and development. Especially in the industrialization level of technical current situation and the reality of China's demand to still have bigger difference. Although from a longitudinal look at our country develops very fast, but transverse than ( contrast with abroad ) not only technical level to have difference, insome aspects of development speed also has difference, i.e. the number of sophisticated CNC equipment technical level difference has distensible tendency. Internationally, to our country numerical control technology and industrialization level is estimated as follows. The level of A. technique, with foreign advanced level lags behind about 10 ~ 15 years, in the sophisticated technology is larger. B. industrialization level, the market is had rate is low, breed coverage, has formed the scale of production, functional components of professional production level and complete sets of capacity is low; the appearance quality is relatively poor; reliability; commercialization; domestic CNC system has not been established their own brand, customer confidence. C. sustainable development ability of competition, before NC technology research and development, engineering ability is weaker; CNC technical application field strength is not strong; related standards, research, develop lag, analyse the existence of the gap between the main reason has the following sides, A. recognition. On domestic CNC industry process difficult, the complexity and the long-term characteristic of insufficient understanding; to the market is not standardized, overseas blockade and kill the system difficult underestimate; to our country numerical control technology application level and ability analysis is not enough. B. system, from the technical point of view about numerical control industrialization problem when much, from the system the angle of industrial catenary considering CNC industrialization problem when little; not the establishment of a complete quality system, perfect training, service network support system. C. mechanism of adverse mechanisms causing the loss of talented people, and restricted technology and technical route of innovation, product innovation, and restricts the effective implementation of the project, often the planning ideal, implementation difficulties. D. technology, enterprise technology independent innovation capability is not strong, the core technology of engineering ability is not strong, bed standard is backward, level is low, the new standard is not enough research of CNC system.control technology andindustrial development strategy:( 1) the strategic considerationof our country is a bigmanufacturing country in theworld, in the transfer ofindustry to accept the frontrather than the back transfer,namely to grasp the core technology of advanced manufacturing, or in the new roundinternational industry structural adjustment, our country manufacturing industry willfurther " air core ". Our resources, environment, market price exchange may be thenew world economic pattern in the international " machining center " or " assemblycenters ", rather than to master the core technology of manufacturing center position,this will seriously affect our country with the development of modern manufacturingprocess. First, from the social security, because we should stand in the height ofnational security strategy to take the numerical control technology and the industrycontrol, industry in China is the most populous industry employment, manufacturingindustry development can not only improve the people's living standard, but also canalleviate the pressure of employment of our country social stability; secondly, fromthe defense safety, western developed countries have sophisticated CNC products areclassified as national strategic material for China to realize embargo and restrictions, "Toshiba event " and " the Cox report " is the best example. ( 2) development strategyfrom the perspective of China's basic national conditions, to the needs of nationalstrategy and national economy to market demand-oriented, to improve China'sequipment manufacturing industry comprehensive competitive ability andindustrialization level as the goal, in a systematic way, leading to the beginning of thetwenty-first Century time choice of China's equipment manufacturing industryupgrade key techniques and support industrialization development technology,supporting technology as the research content of the development of equipmentmanufacturing industry leaping development. Emphasize the market demand oriented, i.e. to terminal NC products, to machine ( such as the large volume of CNC lathes, milling machine, high speed and high precision high performance machine tools, key industries and key equipment ) drives the NC industry development, solve CNC system and related functional components ( digital servo system with high speed electric motor, the spindle system and the new equipment accessories ) reliability and scale of production problems. No scale will not have the high reliability of the products; no scale will have low prices and competitive products; of course not the scale of China's CNC equipment finally to have one's day. In the sophisticated equipment research and development, production and research and to emphasize the end user closely, with " do, use, sell out " as the goal, according to the national will to tackle key problem, in order to solve the urgent state. In the competition before the NC technology, emphasis on innovation, emphasis on research and development with independent intellectual property rights of technology and products, to industry of our country numerical control, the equipment manufacturing industry and the manufacturing industry to lay the foundation for sustainable development.加工中心数控技术出处:数控加工中心的分类以及各自特点出版社:化学工业出版社; 第1版(2009年3月16日)作者:徐衡、段晓旭加工中心是典型的集高技术于一体的机械加工设备,它的发展代表了一个国家设计制造的水平也大大提高了劳动生产率,降低了劳动成本,改善了工人的工作环境,降低了工人的劳动强度。
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。
机械类数控车床外文翻译外文文献英文文献数控
数控加工中心技术开展趋势与对策原文来源:Zhao Chang-ming Liu Wang-ju(C Machining Processand equipment,2002,China)一、摘要Equip the engineering level, level of determining the whole national economy of the modernized degree and modernized degree of industry, numerical control technology is it develop new developing new high-tech industry and most advanced industry to equip (such as information technology and his industry, biotechnology and his industry, aviation, spaceflight, etc. national defense industry) last technology and getting more basic most equipment.Numerical control technology is the technology controlled to mechanical movement and working course with digital information, integrated products of electromechanics that the numerical control equipment is the new technology represented by numerical control technology forms to the manufacture industry of the tradition and infiltration of the new developing manufacturing industry,Keywords:Numerical ControlTechnology, E quipment,industry二、译文数控技术和装备开展趋势与对策装备工业的技术水平和现代化程度决定着整个国民经济的水平和现代化程度,数控技术与装备是开展新兴高新技术产业和尖端工业〔如信息技术与其产业、生物技术与其产业、航空、航天等国防工业产业〕的使能技术和最根本的装备。
外文翻译-数控技术和数控装备
翻译资料(英文)NC technology and NC equipmentNC technology and NC equipment manufacturing industry is an important foundation for modernization. This is the basis of a strong direct impact on the country's economic development and comprehensive national strength, and bearing on a country's strategic position. Therefore, the world's industrialized countries have taken significant steps to develop their own technologies and their industrialization NC.In China, the CNC technology and equipment development has also been a high degree of attention in recent years has made considerable progress. Particularly in the area of general computer numerical control, PC-based platform for domestic CNC systems, has been at the forefront of the world. China, however, is in NC technology research and development industries also have many problems, particularly in the ability of technological innovation and commercialization process, and other aspects of market share is even more conspicuous. In the arrival of the new century, how to effectively solve these problems, China's NC areas along the path of sustainable development, from the overall comprehensive entered the ranks of the advanced world, we in the international competition in a pivotal position, will be NC research and development departments and manufacturers facing the important task.To accomplish this task, first of all, must be established in line with China's national conditions and development. Therefore, this article from the overall strategic and technical level and two line CNC system, functional components, NC complete machine, and several specific aspects of the development in the new century means.1 Development with Chinese characteristics and a new generation of PC NC systemNC system is the core of all types of CNC equipment, first through the development of scientific and technological innovation with Chinese characteristics, the new NC system, will be to promote the industrialization process of NC effective technical means.Practice has proven that the past 10 years we are moving in the PC NC road is completely correct. PC machines (including industrial PC) output is big, cheap, technological progress, and quickly improve performance, and high reliability (MTBF host PC industry has reached 30 [3]). Therefore, as a CNC system with the hardware and software platform can greatly improve the cost-NC system, but also make full use of existing generic computer hardware and software resources and sharing the latest achievements in the field of computers, such as large memory capacity, high - color display, multimedia information exchange, networking andcommunications. In addition, as the common computer platform can also access NC rapid technological progress, when PC-upgrading, NC system can also be corresponding upgrades to maintain long-term technical advantages in the competition to be invincible.At present, the PC architecture CNC system comes in two main forms: (1) for the front of the PC and NC composite structure; (2) General and PC-card-hierarchical structure. Another is the development of a number of distributed architecture. DSP will be its programmer is composed of digital servo through the media, such as fiber optic cable network to link up with the NC device, the NC formed a complete system. Although the performance of this system is very good, but because of the high costs of development and production, the recent difficult to be accepted by domestic users. We believe that the above-mentioned structure is not in line with China's national conditions the best solution to China's national conditions should be allfull-function CNC Software's integrated structure, such as the structure of the smallest hardware, and is conducive to lower system costs, but, more importantly, can effectively improve the reliability of the system.Decades of experience show that the reliability of domestic CNC system is good or bad can the key to development. Although the NC system reliability impact of a number of factors, but the large-scale hardware and the hardware manufacturers lower level of reliability tend to pose the greatest threat. Previously, domestic CNC system in the design, the limit for a variety of reasons, do not have to use too much technical indicators ordinary CPU, so, for the completion of the complex function NC often need more CPU to component systems, and sometimes plus some special need or common hardware circuit NC system to achieve real-time high of some functions (such as small interpolation, position servo control, etc.), resulting in large-scale system hardware. NC system for small quantities of such products in the country under the conditions of the existing process, it is difficult from the perspective of hardware manufacturers ensure that the reliability of the system As a result, domestic production in the NC system at the poor performance of the domestic few control system the image and reputation of a serious impact makes many users now also fear.Therefore, we in the development of the new NC system, priority should be given to selection of new high-performance CPU (such as the high-speed Pentium II, Pentium III, etc.) as a system and control core computing, and software to achieve as far as possible all the features of NC . This can drastically reduce the size of the system hardware. Also, the software design, power supply design, the design and selection of connectors, grounding and shielding design and construction, such as the adoption of strong anti-nuisance high reliability design and manufacturing technology, and thereby improve the reliability of the system.Since a new high-performance CPU can replace dozens of ordinary CPU (such as the80286,80386, etc.), therefore, based on the high-performance CPU on the PC platform, not only can fulfill the basic functions of CNC system (such as information processing, knives meeting, interpolation, acceleration and deceleration control, etc.) and on-off control function (PLC contents), but also to be completed servo control functions. Thus, before the completion of the DSP digital servo control functions (such as position control, speed control, transformation vector control, etc.) from a PC can be completed in the CPU, thus realizing the contents of servo controls, which not only effectively reduce the size of the hardware part of NC , but also significantly reduce the servo control of the hardware scale.Such contents PLC and servo control of the entire contents of the integrated software CNC system, the hardware will reach its minimum, the entire CNC system, in addition to a PC platform, the only remaining driver of the sports machine interface and feedback power interface. This not only effectively improve the reliability of the system, eliminating the transmission of information bottlenecks, improve system performance, but can also significantly reduce system cost, the system (including motor) to the existing price will be about half the CNC system. Obviously, this high performance, high reliability, low cost, the new NC system is highly competitive, is expected to open up a new situation in China to contribute to NC.In addition, the integration of PC NC system there is a big advantage, that is easy to achieve open architecture. This is because such a system is the hardware itself has been completely open, open a CNC system completely in software, as long as the proper formulation of standards and protocols, information processing, path interpolation, acceleration and deceleration control, Switch control to servo control can be achieved and opening up, thus greatly facilitate user access.2 NC components advancing specialized productionNC system to resolve the problem, how to achieve CNC machine tool design and manufacture of modular machine tool manufacturing enterprises in China is the rapid response to market demand, competition won another key. CNC machine tools to achieve the design and manufacture of modular, we must solve the NC machine tool components of specialized production. China in this regard from the actual demand there is still a considerable gap. Therefore, in the next few years, we must vigorously promote the CNC machine tool components and the development of specialized production. The main points are as follows:(1) New permanent magnet electric spindle, spindle units on the international market has become the most popular CNC machine tool features. But almost all of these products for asynchronous induction type, presence following major problems: ① there rotor windings, high current flow, heat rotor serious direct impact on the spindle precision; ② small and low-speedoutput torque ripple, be difficult to meet the wide range of cutting requirements; ③ efficiency and low power factor, not only motor size and weight requirements of the inverter and a large capacity, energy and more complex ④ control system, the high cost.(2) Cheap, high-performance servo system is, a feed AC servo system (motor + drive) prices are generally in the million more than the price axis servo system up to a few million, has become a lower domestic CNC machine tools the cost of a major obstacle. Therefore, should be in line with the new integrated domestic CNC system development, vigorously develop the contents of cheap, high-performance servo system. The contents of the hardware only servo motor and power interface, and make full use of China's permanent resource advantages, and specialized production by the motor can cost down, and the intelligent use of IPM as a power module interfaces are cheap, will be the contents of feed servo control in the price of several thousand dollars within, the contents of spindle servo control in the price of less than 20,000 yuan, it is entirely possible.(3) linear AC servo system linear AC servo system is the next century CNC machine tool indispensable components, the present China has not yet mature product, it should strengthen the research, development and application. Taking into account conventional machine Magnetically-shielded problem more difficult to solve, and the Magnetically-shielded PMT relatively easy, conventional structure for the development of machine-linear asynchronous induction motor, parallel structure for the development of permanent magnet synchronous machine type linear motor, thereby exceed and with a practical application of a new-typehigh-speed high-precision feed system. On this basis, the drive will be further developed with the support of the combined magnetic levitation table.(4) high-speed high-precision detection device is high-speed high-precision CNC machine tool development of the next century is the main theme and not only need high-performance control and drive, but also need high-quality examination link, it should be based on existing technology, further development of 0.1 μ m above the precision of high-speed (60 m / min or more) and linear displacement sensor 1 million pulses / r the angular displacement sensor, such technology is abroad on China's blockade.3 CNC machine tools to accelerate production of the country, and win market overtakeNC industrialization of ultimate success will be reflected in the CNC machine tool production and market share. In the overall strategic guidance, the implementation of grasping two (low-efficiency and high-speed CNC machine tool CNC Machine), with the middle (generalCNC machine tool), and promoting heavy (heavy equipment key) approach, in the domestic market will be fast recover the lost land, in the international market steady advance toward the end to fight domestic CNC machine tool market overtake an effective tactics and strategies. On the general development of CNC machine tools has made numerous articles devoted to, the following low-only NC machine tools, high-speed CNC machine tools and heavy efficient CNC machine tool development issues are discussed.(1) Vigorously develop low-cost CNC machine tool is the low-cost machine functions to meet user requirements (no functional waste), technical indicators moderate, reliability, and the popularity of cheap NC machine tools. Such machines have become an international market trends in the development of CNC machine tools, and is one of many domestic users aspirations of the product, a broad market prospect. However, if a foreign NC system (including servo) in accordance with the traditional way of thinking to develop low-cost machine, it is difficult to cut their prices to be acceptable to the vast number of users level. Thus, the application of this new type of integration of the domestic CNC system to the development of high-performancelow-cost CNC machine tools, will be one of the most successful road hope. As long as a certain volume, which constitutes the middle of the universal CNC lathe can control the price at 100,000 yuan within the 3D CNC milling machine can be controlled in 15 million, the processing centre can be controlled at 20 million . The price of domestic CNC machine tools will be a stronger competitive.(2) To accelerate the development of efficient high-speed high-speed CNC machine tool CNC machine tool development efficiency are another major trend. Development of efficient high-speed CNC machine tool technology can be a way to the following: ① through increased cutting speed and feed rate, doubling their production to achieve efficient and effective processing improve the surface quality of parts and machining accuracy and solve difficult to resolve conventional processing some special materials (such as aluminum titanium, mold steel, hardened steel) and the special shape of components (such as complex thin-walled parts) efficient processing problems. ② through the composite process, reduce the number of the installation of the work piece, effectively shorten the handling and clamping time. For example, five 5-axis machining center with a composite legislation cars universal machining centre will achieve a complete card with the majority of parts (or all) processing. ③ circle in a high-speed high-precision milling and processing hole in a spiral path interpolation does not realize the direct drilling Bottom Tapping new processing methods, and substantial reductions in the number of ATC and improve processing efficiency. ④ CNC machine tool development for intelligent searching machining functions, and the elimination of artificial precision fixture is to find the dependence of the effective shortening of single pieces of small-batch processing time toprepare.(3) breakthrough heavy CNC machine tool design and manufacturing technology heavy CNC machine tool (especially heavy multi-axis CNC machine tools) is the national economy and national defense production of critical equipment, are strategic commodities, real advanced heavy foreign NC Machine Tool it is impossible to sell us, therefore, in our country the next century NC product development must rely on its own strength to solve. CNC machine tool development must have a heavy perfect basis, we in CNC machine tools in the process of China should constantly sum up experience, strengthen basic research and key technologies, and give full play to China's advantages of combining production and research, the collaboration of different departments together strive to make a breakthrough early in the next century progress.At present, the development of CNC machine tools, in addition to heavy need to strengthen basic theoretical research, but also to strengthen their research of key technologies. For example, heavy machine control is a special need to be resolved key issues. Due to heavy machining of work pieces not particularly expensive scrapped, in order to ensure that the machine is reliable and in the CNC system of dual-use (or) CPU redundancy programmer of work to ensure that the operation and control of the absolutely correct, and in the event of failure automatic diagnosis, auto repair or replacement automatically ensure that no processing problems. In addition, the power supply can be taken on the dual-battery-powered electricity-wide isolation, that is a battery power supply to the system, to be carried out on another group of rechargeable batteries, power grids and control system is completely isolated. This workshop complete elimination of the heavy fluctuations in the power grid voltage powerful, serious interference on the impact of the NC system, which effectively guarantee the reliability of the system. Again, heavy machine-driven CNC is a key issue. When the stroke length is more than 5 m, it will be difficult to ordinary competent Ball screw load transmission, the current general increase of pre-loaded double gear - rack, HIP worm - the mother of the cochlear institutions, the four foot (or feet) Crawling into the institutions to achieve long trip drive. However, the existence of these programmers complex structures, and low velocity and acceleration, dynamic performance difference, it is difficult to achieve high-precision, complex issues such as maintenance. This could be the development of highly efficient array of linear motor direct drive technology and space technology-driven parallel mechanism, a new way to solve the heavy high-speed CNC machine tools, precision-driven issue. In addition, the optimization of the structure of machine design, a long stroke sophisticated detection, gravity deformation compensation cutting deformation compensation, heat distortion compensation is also heavy NC Machine Tool key issues must be resolved, must be full attention.Develop in line with China's national conditions in the overall development strategy, withthe international standards established path of development in the 21st century, China's CNC technology and industrial development. In this paper, CNC technology and industrial development trends of the NC field of the issues on the basis of the CNC China in the 21st century technology and the development of the industry means were discussed, put forward a scientific and technological innovation as the pilot to commercialization is the mainstay for the management and marketing, with the focus on technical support and services as a shield and adhere to the road of sustainable development of the overall development strategy. On this basis, on the development of new NC system, NC functional components, such as the NC Machine Tool specific technical means.We sincerely hope that our technology, industry and the education sector co-operation, a good grasp of the knowledge economy to bring us the rare opportunity to compete severe challenges brought about by globalization, in the 21st century so that our technology and industry to NC in the forefront of the world, China's economy maintained a strong momentum of development efforts and struggle!翻译资料(中文)数控技术和数控装备数控技术和数控装备是制造工业现代化的重要基础。
数控技术英语作文
数控技术英语作文English:Numerical Control (NC) technology, also known as Computer Numerical Control (CNC), is a revolutionary advancement in manufacturing processes. It integrates computer systems with machinery to control and automate various operations such as cutting, milling, drilling, and shaping of materials with unparalleled precision and efficiency. One of the key components of NC technology is the CNC machine, which operates based on coded instructions programmed into the computer system. These instructions dictate the movements and actions of the machine's tools, allowing for highly accurate and complex manufacturing tasks to be carried out consistently. NC technology has transformed the manufacturing industry by significantly reducing production times, minimizing errors, and enabling the production of intricate components that were previously unattainable. Moreover, CNC machines can be easily reprogrammed to accommodate changes in production requirements, offering manufacturers greater flexibility and adaptability in responding to market demands. With continuous advancements in software and hardware, NC technology continuesto evolve, pushing the boundaries of what is achievable in modern manufacturing processes.中文翻译:数控技术,也称为计算机数控(CNC),是制造过程中的一项革命性进步。
(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)。
数控技术(双语)
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Chapter1 Introduction to numerical control Interpolation
机械工程学院
数控技术(双语)
Numerical Control Technology
董长双
2013.7 1
Chapter1 Introduction to numerical control
1.1 Fundamentals of NC technology 1.1.1 Development history of NC
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Chapter1 Introduction to numerical control
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Chapter1 Introduction to numerical control
1.1.3 Basic component of NC machine tools
The work process of NC
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Chapter1 Introduction to numerical control
1.2.2 Types of NC servo-drive system
1. Open-loop servo drive
CNC 插补指令
脉冲频率f 脉冲个数n
换算
f、n
脉冲环 形分配
变换
A相、B相 功率 放大
C相、…
turning, drilling, milling, grinding NC lathe, NC boring mill, NC drill press, NC milling machine, NC grinding machine, machine center. Multifunction NC machines with automatic tool changer and tool storage. 2. Non-machine tool application Punch press, sheet metal bending, welding machine, thermal cutting machine ( oxfuel cutting, laser cutting, plasma arc cutting), tube bending machine.
机械类数控外文翻译外文文献英文文献数控
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 representsthe 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 statementssimilar 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 representedgiant 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 itwas 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 rigorsof 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 associatedwith 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, likefiltering 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/usagegroup. Many of the largest manufacturers, like Texas Instruments and Motorola, offer both specialised DSP for certain'fieslds like motor -control or modems ,and general highp- erformance 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' sth at allows the programmer to implement complex processing algorithms using simple “drag ‘n' drop ” methodologies.DSP's more or less fall into two 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 “generaplurpose ”register , making them quite tricky to program and more importantly ,making C-compilers inherently inefficient. Floating-point DSP'sbehave more like common general-purpose CPU's ,with re g i s-tfei l er s .There are thousands of different DSP 's on the market, and it is difficult task finding themost 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 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 o 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 differenton-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 ‘C24xdevicesprovides 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 , andstate control. The ‘ C24x DSP controller offer reliability and programmability . Analog control systems, on the other hand ,are hardwiredsolutions 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 astraditional 8-and 16-bit microcontrollers. The instruction set also allows you to retain your software investment when moving from other general-purpose‘ C2xx generation ,source code compatible with the ' C2gxeneration , and upwardly source code compatible with the ‘ C5x generation of DSPs from Texas Instruments.The ‘C24x architecture is also w-eslul ited 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 resonancesin a system or an estimation technique that could eliminate state sensors in a system.The ‘ C24xDSP controllers take advantage of an set of peripheraful nctions 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 matrpkleace.The TMS320F/C240 is the first standard device introduced in the ‘ 24x series of DScontrollers. It sets the standard for a singlec-hip 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 necessfaorryhigh-speed signal processing anddigital control functions, and it has the peripherals needed to provide a single-chip solution for motor control applications. The ‘ 240is 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 climate control---Appliance and HVAC 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 ‘ 240is 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 'oswn compare register, support 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 avariety 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 disadvantageof 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 human being 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。
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
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。
机械毕业设计外文翻译---数控机床
What Is CNCCNC stands for Computer Numerical Control and has been around since the early 1970''s. Prior to this, it was called NC, for Numerical Control. (In the early 1970''s, computers were introduced in these controls, hence the name changed)While people in most walks of life have never heard of this term, CNC has touched almost every form of manufacturing process in one way or another. If you''ll be working in manufacturing, it''s likely that you''ll be dealing with CNC on a regular basis.Before CNCWhile there are exceptions to this statement, CNC machines typically replace (or work in conjunction with) some existing manufacturing process/es. Take one of the simplest manufacturing processes, drilling holes, for example.A drill press can of course be used to machine holes. (It''s likely that almost everyone has seen some form of drill press, even if you don''t work in manufacturing.) A person can place a drill in the drill chuck that is secured in the spindle of the drill press. They can then (manually) select the desired speed for rotation (commonly by switching belt pulleys), and activate the spindle. Then they manually pull on the quill lever to drive the drill into the workpiece being machined.As you can easily see, there is a lot of manual intervention required to use a drill press to drill holes. A person is required to do something almost every step along the way! While this manual intervention may be acceptable for manufacturing companies if but a small number of holes or workpieces must be machined, as quantities grow, so does the likelihood for fatigue due to the tediousness of the operation. And do note that we''ve used one of the simplest machining operations (drilling) for our example. There are more complicated machining operations that would require a much higher skill level (and increase the potential for mistakes resulting in scrap workpieces) of the person running the conventional machine tool. (We commonly refer to the style of machine that CNC is replacing as the conventional machine.)By comparison, the CNC equivalent for a drill press (possibly a CNC machining center or CNC drilling & tapping center) can be programmed to perform this operation in a much more automatic fashion. Everything that the drill press operator was doing manually will now be done by the CNC machine, including: placing the drill in the spindle, activating the spindle, positioning the workpiece under the drill, machining the hole, and turning off the spindle.How CNC worksThere is another article included in this web site called The Basics of CNC that explains how to program, setup, and operate CNC machines in greater detail. Additionally, we offer a series of products aimed at helping you learn how to use CNC machines. Here we''re relating how CNC works in very general terms.As you might already have guessed, everything that an operator would be required to do with conventional machine tools is programmable with CNC machines. Once the machine is setup and running, a CNC machine is quite simple to keep running. In fact CNC operators tend to get quite bored during lengthy production runs because there is so little to do. With some CNC machines, even the workpiece loading process has been automated. (We don''t mean toover-simplify here. CNC operators are commonly required to do other things related to the CNC operation like measuring workpieces and making adjustments to keep the CNC machine running good workpieces.)Let''s look at some of the specific programmable functions.Motion controlAll CNC machine types share this commonality: They all have two or more programmable directions of motion called axes. An axis of motion can be linear (along a straight line) or rotary (along a circular path). One of the first specifications that implies a CNC machine''s complexity is how many axes it has. Generally speaking, the more axes, the more complex the machine.The axes of any CNC machine are required for the purpose of causing the motions needed for the manufacturing process. In the drilling example, these (3) axis would position the tool over the hole to be machined (in two axes) and machine the hole (with the third axis). Axes are named with letters. Common linear axis names are X, Y, and Z. Common rotary axis names are A, B, and C.Programmable accessoriesA CNC machine wouldn''t be very helpful if all it could only move the workpiece in two or more axes. Almost all CNC machines are programmable in several other ways. The specific CNC machine type has a lot to do with its appropriate programmable accessories. Again, any required function will be programmable on full-blown CNC machine tools. Here are some examples for one machine type.Machining centersAutomatic tool changerMost machining centers can hold many tools in a tool magazine. When required, the required tool can be automatically placed in the spindle for machining.Spindle speed and activationThe spindle speed (in revolutions per minute) can be easily specified and the spindle can be turned on in a forward or reverse direction. It can also, of course, be turned off.CoolantMany machining operations require coolant for lubrication and cooling purposes. Coolant can be turned on and off from within the machine cycle.The CNC programThink of giving any series of step-by-step instructions. A CNC program is nothing more than another kind of instruction set. It''s written in sentence-like format and the control will execute it in sequential order, step by step.A special series of CNC words are used to communicate what the machine is intended to do. CNC words begin with letter addresses (like F for feedrate(馈送率), S for spindle speed, and X, Y & Z for axis motion). When placed together in a logical method, a group of CNC words make up a command that resemble a sentence.For any given CNC machine type, there will only be about 40-50 words used on a regular basis. So if you compare learning to write CNC programs to learning a foreign language having only50 words, it shouldn''t seem overly difficult to learn CNC programming.The CNC controlThe CNC control will interpret a CNC program and activate the series of commands in sequential order. As it reads the program, the CNC control will activate the appropriate machine functions, cause axis motion, and in general, follow the instructions given in the program.Along with interpreting the CNC program, the CNC control has several other purposes. All current model CNC controls allow programs to be modified (edited) if mistakes are found. The CNC control allows special verification functions (like dry run) to confirm the correctness of the CNC program. The CNC control allows certain important operator inputs to be specified separate from the program, like tool length values. In general, the CNC control allows all functions of the machine to be manipulated.What is a CAM system?For simple application (like drilling holes), the CNC program can be developed manually. That is, a programmer will sit down to write the program armed only with pencil, paper, and calculator. Again, for simple applications, this may be the very best way to develop CNC programs.As applications get more complicated, and especially when new programs are required on a regular basis, writing programs manually becomes much more difficult. To simplify the programming process, a computer aided manufacturing (CAM) system can be used. A CAM system is a software program that runs on a computer (commonly a PC) that helps the CNC programmer with the programming process. Generally speaking, a CAM system will take the tediousness and drudgery out of programming.What is a DNC system?Once the program is developed(either manually or with a CAM system), it must be loaded into the CNC control. Though the setup person could type the program right into the control, this would be like using the CNC machine as a very expensive typewriter. If the CNC program is developed with the help of a CAM system, then it is already in the form of a text file . If the program is written manually, it can be typed into any computer using a common word processor (though most companies use a special CNC text editor for this purpose). Either way, the program is in the form of a text file that can be transferred right into the CNC machine. A distributive numerical control (DNC) system is used for this purpose.A DNC system is nothing more than a computer that is networked with one or more CNC machines. Until only recently, rather crude serial communications protocol (RS-232c) had to be used for transferring programs. Newer controls have more current communications capabilities and can be networked in more conventional ways (Ethernet, etc.). Regardless of methods, the CNC program must of course be loaded into the CNC machine before it can be run.中文翻译:什么数控机床数控机床代表计算机数字控制机床,并且从20世纪70年代以来一直受到人们的关注。
数控机床外文文献翻译、中英文翻译
1 原文一CNC machine tools Outdate, J. and Joe, J. Configuration Synthesis of Machining Centers with Tool ,John Wiley & sons, 2001 While 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 The first first first benefit benefit benefit offered offered offered by by by all all all forms forms forms of of of CNC CNC CNC machine machine machine tools tools tools is is is improved improved automation. automation. The The The operator operator operator intervention intervention intervention related related related to to to producing producing producing work work work pieces pieces pieces can can can be be reduced reduced or or or eliminated. eliminated. eliminated. Many Many Many CNC CNC CNC machines machines machines can can can run run run unattended unattended unattended during during during their their their entire entire machining machining cycle, cycle, cycle, freeing freeing freeing the the the operator operator operator to to to do do do other other other tasks. tasks. tasks. This This This gives gives gives the the the CNC CNC CNC user user several several side side side benefits benefits benefits including including including reduced reduced reduced operator operator operator fatigue, fatigue, fatigue, fewer fewer fewer mistakes mistakes mistakes caused caused caused by by human human error, error, error, and and and consistent consistent consistent and and and predictable predictable predictable machining machining machining time time time for for for each each each work work work piece. 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 a nd accurate work and accurate work pieces. Today'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 tools is flexibility. Since these these machines machines machines are are are run run run from from from programs, programs, programs, running running running a a a different different different workpiece workpiece workpiece is is is almost almost almost as 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 CNC The The most most most basic basic basic function function function of of of any any any CNC CNC CNC machine machine machine is is is automatic, automatic, automatic, precise, precise, precise, and and consistent consistent motion motion motion control. control. control. Rather Rather Rather than than than applying applying applying completely completely completely mechanical mechanical mechanical devices devices devices to to cause cause motion motion motion as as as is is is required required required on on on most most most conventional conventional conventional machine machine machine tools, tools, tools, CNC CNC CNC machines machines allow motion control in a revolutionary manner2. All forms of CNC equipment have two two or or or more more more directions directions directions of of of motion, motion, motion, called called called axes. axes. axes. These These These axes axes axes can can can be be be precisely precisely precisely and and automatically automatically positioned positioned positioned along along along their their their lengths lengths lengths of of of travel. travel. travel. The The The two two two most most most common common common axis 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 programmed commands. commands. commands. Generally Generally Generally speaking, speaking, speaking, the the the motion motion motion type type type (rapid, (rapid, (rapid, linear, linear, linear, and 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 feedback device (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 tool Though 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 systems It 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 motion amount4. amount4. amount4. (This (This (This would would would be be be like like like having having having to to to figure figure figure out out out how how how many many many turns turns turns of of of the 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 a much simpler and more logical logical way way way by by by utilizing utilizing utilizing some some some form form form of of of coordinate coordinate coordinate system. system. system. The The The two two two most most most popular popular coordinate coordinate systems systems systems used used used with with with CNC CNC CNC machines machines machines are are are the the the rectangular rectangular rectangular coordinate coordinate coordinate system system and and the the the polar polar polar coordinate coordinate coordinate system. system. system. By By By far, far, far, the the the more more more popular popular popular of of of these these these two two two is is is the the rectangular coordinate system. The program zero point establishes the point of reference for motion commands in in a a a CNC CNC CNC program. program. program. This This This allows allows allows the the the programmer programmer programmer to to to specify specify specify movements movements movements from from from a a common common location. location. location. If If If program program program zero zero zero is is is chosen chosen chosen wisely, wisely, wisely, usually usually usually coordinates coordinates coordinates needed needed needed for for the program can be taken directly from the print. With this technique, if the programmer wishes the tool to be sent to a position one one inch inch inch to to to the the the right right of of the the the program program program zero zero zero point, point, point, X1.0 X1.0 X1.0 is is is commanded. commanded. If If the 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 motion All 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), end points for motions are are specified specified specified from from from the the the tool's tool's tool's current current current position, position, position, not not not from from from program program program zero. zero. zero. With With With this this method method of of of commanding commanding commanding motion, motion, motion, the the the programmer programmer programmer must must must always always always be be be asking asking asking "How "How "How far far should should I I I move move move the the the tool?" tool?" tool?" While While While there there there are are are times times times when when when the the the incremental incremental incremental mode mode mode can can can be 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 Be careful careful careful when when when making making making motion motion motion commands. commands. commands. Beginners Beginners Beginners have have have the the the tendency tendency tendency to to think think incrementally. incrementally. incrementally. If If If working working working in in in the the the absolute absolute absolute mode mode mode (as (as (as beginners beginners beginners should), should), should), the 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 Aside from from from making making making it it it very very very easy easy easy to to to determine determine determine the the the current current current position position position for for for any 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 one command command command of of of the the the program, program, program, only only only one one one movement movement movement will will will be be be incorrect. incorrect. incorrect. On On On the the the other other hand, if a mistake is made during incremental movements, all motions from the point of the mistake will also be incorrect. Assigning program zero Keep 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. program. With this With this method, the programmer tells the control how far it is from from the the program program zero point to zero point to t he starting position of the machine. This the starting position of the machine. This is is commonly done commonly done with a G92 (or G50) command at least at the beginning of the program and possibly at 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 G54 Flexible manufacturing cells A 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 the central computer. Instead, instructions from the central computer are passed to the cell controller. 2. The cell is limited in the number of part families it can manufacture. The following elements are normally found in an FMC: • Cell controller • Programmable logic controller (PLC) • More than one machine tool • A materials handling device (robot or pallet) The The FMC FMC FMC executes executes executes fixed fixed fixed machining machining machining operations operations operations with with with parts parts parts flowing flowing flowing sequentially sequentially between operations. High speed machining The term High Speed Machining (HSM) commonly refers to end milling at high rotational rotational speeds speeds speeds and and and high high high surface surface surface feeds. feeds. feeds. For For For instance, instance, instance, the the the routing routing routing of of of pockets pockets pockets in 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 60 years, HSM years, HSM has been applied to a wide range of metallic and non-metallic workpiece materials, including the the production production production of of of components components components with with with specific specific specific surface surface surface topography topography topography requirements requirements requirements and and machining machining of of of materials materials materials with with with hardness hardness hardness of of of 50 50 50 HRC HRC HRC and and and above. above. above. With With most most steel steel components components hardened hardened hardened to to to approximately approximately approximately 32-42 32-42 32-42 HRC, HRC, HRC, machining machining machining options options options currently currently include: Fig.5 cutting data rough rough machining machining machining and and and semi-finishing semi-finishing semi-finishing of of of the the the material material material in in in its its its soft soft soft (annealed) (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 cutting tools) tools) tools) finishing finishing finishing and and and super-finishing super-finishing super-finishing of of of cylindrical/flat/cavity cylindrical/flat/cavity cylindrical/flat/cavity surfaces surfaces surfaces with with appropriate cemented carbide, cermets, solid carbide, mixed ceramic or polycrystalline cubic boron nitride (PCBN) For many components, the production process involves a combination of these options options and and and in in in the the the case case case of of of dies dies dies and and and moulds moulds moulds it it it also also also includes includes includes time time time consuming consuming consuming hand 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 HSM Survival The The ever ever ever increasing increasing increasing competition competition competition in in in the the the marketplace marketplace marketplace is is is continually continually continually setting setting setting new 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... Materials The development of new, more difficult to machine materials has underlined the necessity necessity to to to find find find new new new machining machining machining solutions. solutions. solutions. The The The aerospace aerospace aerospace industry industry industry has has has its its its heat heat resistant resistant and and and stainless stainless stainless steel steel steel alloys. alloys. alloys. The The The automotive automotive automotive industry industry industry has has has different different different bimetal bimetal compositions, Compact Graphite Iron and an ever increasing volume of aluminum3. The The die die die and and and mould mould mould industry industry industry mainly mainly mainly has has has to to to face face face the the the problem problem problem of of of machining machining machining high high hardened tool steels, from roughing to finishing. Quality The The demand demand demand for for for higher higher higher component component component or or or product product product quality quality quality is is is the the the result result result of of of ever ever increasing competition. HSM, if applied correctly, offers a number of solutions in this area. Substitution of manual finishing is one example, which is especially important on dies and moulds or components with a complex 3D geometry. Processes The 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 processes can can can also also also be reduced or eliminated with be reduced or eliminated with HSM. Design & development One of the main tools in today's competition is to sell products on the value of novelty. novelty. The The The average average average product product product life life life cycle cycle cycle on on on cars cars cars today today today is is is 4 4 4 years, years, years, computers computers computers and and accessories accessories 1.5 1.5 1.5 years, years, years, hand hand hand phones phones phones 3 3 3 months... months... months... One One One of of of the the the prerequisites prerequisites prerequisites of of of this this development of fast design changes and rapid product development time is the HSM technique. Complex products There is an increase of m ulti-functional multi-functional multi-functional surfaces surfaces surfaces on components, such on components, such a s new as new design design of of of turbine turbine turbine blades blades blades giving giving giving new new new and and and optimized optimized optimized functions functions functions and and and features. features. features. Earlier 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 equipment The The strong strong strong development development development of of of cutting cutting cutting materials, materials, materials, holding holding holding tools, tools, tools, machine machine machine tools, tools, controls and especially CAD/CAM features and equipment, has opened possibilities that must be met with new production methods and techniques5. Definition of HSM Salomon's Salomon's theory, theory, theory, "Machining "Machining "Machining with with with high high high cutting cutting cutting speeds..." speeds..." speeds..." on on on which, which, which, in in in 1931, 1931, took out a German patent, assumes that "at a certain cutting speed (5-10 times higher than than in in in conventional conventional conventional machining), machining), machining), the the the chip chip chip removal removal removal temperature temperature temperature at at at the the the cutting cutting cutting edge edge will start to decrease...".See fig.6. Fig.6 chip removal temperature as a result of the cutting speed Given Given the the the conclusion:" ... conclusion:" ... seems seems to to to give give give a a a chance chance chance to to to improve improve improve productivity productivity productivity in in machining with conventional tools at high cutting speeds..." Modern research, unfortunately, has not been able to verify this 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 Given today's today's today's technology, technology, technology, "high "high "high speed" speed" speed" is is is generally generally generally accepted accepted accepted to to to mean mean mean surface 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 being used. used. used. One One One trend trend trend which which which is is is very very very evident evident evident today today today is is is the the the use use use of of of very very very large large large cutter 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 MC The The following following following is is a a list list list of of of required required required regular regular regular maintenance maintenance for for a a a Horizontal 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 center Daily Top Top off off off coolant coolant coolant level level level every every every eight eight eight hour hour hour shift shift shift (especially (especially (especially during during during heavy heavy heavy TSC 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. Weekly • Check for proper operation of auto drain on filter regulator. See fig. 8 Fig. 8 way lube and pneumatics On 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 For machines machines machines with with with the the the TSC TSC TSC option, option, option, place place place a a a dab dab dab of of of grease grease grease on on on the the the V-flange V-flange V-flange of of tools. Do this monthly for machines without the TSC option. Clean exterior surfaces with mild cleaner. DO NOT use solvents. 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". Monthly Check 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 Clean the the the locating locating locating pads pads pads on on on the the the A-axis A-axis A-axis and and and the the the load load load station. station. station. This This This requires requires removing the pallet. • Inspect Inspect way way way covers covers covers for for for proper proper proper operation operation operation and and and lubricate lubricate lubricate with with with light light light oil, oil, oil, if if necessary. Six months Replace coolant and thoroughly clean the coolant tank. Check all hoses and lubrication lines for cracking. Annually • Replace 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 Mineral cutting cutting cutting oils oils oils will will will damage damage damage rubber rubber rubber based based based components components components throughout throughout throughout the the machine. Troubleshooting This section is intended for use in determining the solution to a known problem. Solutions Solutions given given given are are are intended intended intended to to to give give give the the the individual individual individual servicing servicing servicing the the the CNC CNC CNC a a a pattern pattern pattern to to follow in, first, determining the problem's source and, second, solving the problem. Use common sense Many Many problems problems problems are are are easily easily easily overcome overcome overcome by by by correctly correctly correctly evaluating evaluating evaluating the the the situation. situation. situation. All 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 Don't suspect suspect suspect machine machine machine accuracy accuracy accuracy if if if the the the vise vise vise bends bends bends the the the part. part. part. Don't Don't Don't claim claim claim hole hole miss-positioning if you don't first center-drill the hole. Find the problem first Many Many mechanics mechanics mechanics tear tear tear into into into things things things before before before they they they understand understand understand the the the problem, problem, problem, hoping hoping that it will appear as they go. We know this from the fact that more than half of all warranty warranty returned returned returned parts parts parts are are are in in in good good good working working working order. order. If If the the the spindle spindle spindle doesn't doesn't doesn't turn, turn, remember remember that that that the the the spindle spindle spindle is is is connected connected connected to to to the the the gear gear gear box, box, box, which which which is is is connected connected connected to to to the the spindle spindle motor, motor, motor, which which which is is is driven driven driven by by by the the the spindle spindle spindle drive, drive, drive, which which which is is is connected connected connected to to to the the the I/O I/O BOARD, BOARD, which which which is is is driven driven driven by by by the the the MOCON, MOCON, MOCON, which which which is is is driven driven driven by by by the the the processor. processor. processor. The 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 machine There 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, y ou will incorrectly install it or break 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, board, reconnect reconnect reconnect and and and reload, reload, reload, and and and if if if you you you make make make one one one mistake mistake mistake or or or bend bend bend one one one tiny tiny tiny pin pin pin it it WON'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. 。
数控专业的英语作文带翻译
数控专业的英语作文带翻译Title: The Development of CNC Technology。
With the rapid development of technology, CNC (Computer Numerical Control) technology has become an indispensable part of modern manufacturing industry. It hasrevolutionized the traditional manufacturing processes by automating and improving efficiency, accuracy, andflexibility in various industries.CNC technology utilizes computer programs to control machine tools and equipment, allowing for precise and complex operations that were previously impossible with manual methods. This technology has greatly increased productivity and reduced production costs for manufacturers, making it a popular choice for producing a wide range of products, from automotive parts to aerospace components.One of the key advantages of CNC technology is itsability to produce high-quality and consistent productswith minimal human intervention. This not only improves the overall quality of the products but also reduces the riskof errors and defects, leading to higher customersatisfaction and loyalty.Furthermore, CNC technology has also enabled manufacturers to produce customized products quickly and efficiently. By simply inputting the desired specifications into the computer program, manufacturers can easily create unique products tailored to the specific needs and preferences of their customers.In addition to its manufacturing capabilities, CNC technology has also played a significant role in advancing other industries, such as healthcare, transportation, and construction. For example, CNC machines are used in the medical industry to produce custom implants and prosthetics, while in the transportation industry, CNC technology isused to manufacture precision components for aircraft and automobiles.Looking ahead, the future of CNC technology is bright,with continuous advancements in automation, artificial intelligence, and connectivity. These developments will further enhance the capabilities of CNC machines, making them even more efficient, accurate, and versatile in meeting the evolving demands of the manufacturing industry.In conclusion, CNC technology has significantly transformed the manufacturing industry and will continue to play a crucial role in shaping the future of manufacturing. Its ability to automate processes, improve efficiency, and produce high-quality products has made it an essential tool for manufacturers worldwide. As technology continues to evolve, CNC technology will undoubtedly remain at the forefront of innovation and progress in the manufacturing industry.随着技术的快速发展,数控(Computer Numerical Control)技术已经成为现代制造业不可或缺的一部分。
数控专业中英文翻译
Intelligent Open CNC TechnologyI. Technical OverviewIndustrial countries around the world through the development of CNC technology, a CNC machine tool industry, prompting machinery industry entered a new "modern" stage of historical development, and thus the structure of the national economy has brought great changes. CNC machine tools is not only an important basis for mechanical and electrical industrial equipment, automotive, petrochemical, electronics and other pillar industries, the primary means of production modernization, NC is the third industrial revolution the world is an important content. Output of CNC machine tool industry itself far less automobile, chemical and other industries, but thehigh-performance CNC machine tools to the manufacturing industry has brought the benefits of the high rate of production growth and modernization is to promote national economic development of the huge source of power. In particular, numerical control technology in the manufacturing sector expansion and extension of the role and the resulting ripple effect of radiation on the mechanical manufacturing industry sufficient structure, product structure, specialized division of labor, machining methods and management models, the production of social division of labor, business operational mechanism of profound change.In CNC machine tools are widely used in the numerical control technology, is a machining process using computer control information in a variety of digital computing, processing, and high-performance drive units through the implementation of mechanical components for automatic control of high-tech. The current equipment has been used a lot of CNC machining technology, the most typical and most widespread is the application of CNC machine tools. The machining process of the diversity and complexity of machining parts, CNC machine tools to the specifications, types and properties very different from the complexity of the control parameters, debugging complicated operation, so in general will continue the rapid development of computer technology and its architecture , the modern automatic control theory and modern technology to a new generation of power electronics CNC machine tools, we should emphasize them with "open" and "intelligent" features.1. "Open"Requires a new generation of CNC machine tool control system is an open, modular architecture, its features are: Modular elements in the realization of the system at the same time, there should be standardized between these elements can be provided by the different elements of the buyer free to combine, which can easily constitute a complete system. As follows:--- Elements of the system should be modular, while the interface between the modules must be standardized;--- System software, hardware configuration should be "transparent", "portable";--- System should have the "continuous upgrade" capability.At the same time the mechanical structure of a new generation of CNC machine tools also should be open, should be characterized by:--- Function module components using the machine;--- A "technology plan", "processing database" to users;--- Use of "information technology" will be a reasonable allocation of social resources, manufacturing machinery manufacturing industry gradually establish a perfect virtualization and network-based advanced manufacturing systems, machinery manufacturing resources to be used efficiently, to reduce costs, improve quality, the purpose of reducing manufacturing cycle.2. IntelligentThe so-called intelligent control system, is smart with anthropomorphic features, the numerical control system with simulation, extension, expansion of the intelligent behavior of the knowledge processing activities, such asself-learning, adaptive, self-organization, self-optimizing, Zi calm,self-recognition from planning, self-healing, self-reproduction. Through the intelligent CNC machining accuracy and efficiency of physical testing, modeling, feature extraction, processing system automatically senses the internal state and external environment, to quickly make the best goal of the intelligent decision-making, feed rate, cutting depth , coordinate movement, spindle speed and other parameters in real-time control, so that the processing machine at its best.The current NC system functionality required not only high performance (high-speed, high precision and high reliability), but also includes many smart features, such as the processing of motion planning, reasoning,decision-making ability and perception processing environment, manufacturing, network communication capacity (including the interaction with others), intelligent programming, intelligent databases, intelligent surveillance.Practice has proved that these "intelligent" technology, also used in the 21st century, the adjustment of a new generation of CNC machine tools, use and maintenance of all aspects, so that human intervention greatly simplified, to apply "smart" technology, human machine interface for packaging, to make full use of natural language, artificial Windows interface and simple operation, so that adjustment of the machine, use and maintenance tends to be "fool."Second, the status quo and development trend of domestic and foreign1. Overseas DevelopmentThroughout the history of the development of numerical control technology, is easy to see the development of numerical control technology step through the development of computer technology continues to develop, from 1956 to the present, has gone through four stages as follows:In 1956 -1974, the era of proprietary hardware NC;1975 -1989, the special computer numerical control era, that era of the microprocessor NC (μ PC);In 1990 -1995, BASIC PC's CNC times;Since 1996, started the whole PC open a new stage of intelligent CNC.The first three stages of the NC devices there are the following limitations: --- Not free to select the information from the information network;--- Not open architecture, user interface imperfections, machinery manufacturers and users can not independently numerical control system according to crop needs, the user's own technical know-how is not easy to integrate into, and create their own brand names;--- Can not fully utilize the existing resources of common software;--- Can not be free access to the external condition information;--- Architecture many, is not conducive to mass production, improve reliability and reduce costs, reduce the market supply capacity and competitiveness, while limiting the development of numerical control technology.In recent years the United States, the European Community, Japan and other countries have taken measures, a lot of money, the joint of the plant, or even more countries to study a new generation of numerical control systems, from the foregoing information, the world is in the NC Technology All PC CNC open architecture platform, turning the era, the turn is adapted to computer technology, information technology, network technology, the inevitable result of technological development.As modern machinery industry gradually to flexible, integrated, intelligent direction, so must be stressed that a new generation of numerical control technology to have an open and intelligent features. Developed countries have taken measures in recent years, lots of manpower and financial resources to organize a new generation of superior forces and open architecture CNC with intelligent features technology development and research, including the United States of NGC and OMAC plan, the EC OSACA plan, OSEC plans.CNC machine tool mechanical structure is more inclined to "open", to meet the diverse needs of the modern machinery for processing, a new generation of CNC machine tools has the following characteristics:(1) according to the modular machine structure, the principles of design and manufacturing series in order to shorten lead times, best meet the needs of the user's process.(2) As many parts of NC machine tool quality indicators continue to improve, gradually increase the variety of specifications, a more substantial mechanical and electrical integration, functional parameters of the increasingly numerous and so dedicated to supporting a variety of CNC machine features are fully commercialized, to build a competitive machine tool plant created the conditions.(3) to the users, CNC Machine Tool Plant of the developed countries areactively building completely open product sales service system. Part to establish an open laboratory, establishment of self-service CNC machine operator and maintenance training center.(4) using information network technology to a variety of manufacturing resources in society were based on the rational combination of processing tasks and call the 21st century advanced manufacturing technology development trend, the world's countries are active in research in this area.(5) artificial intelligence technology in the promotion and application of CNC technology. With the continued penetration in the computer field of artificial intelligence and development of the intelligent CNC system development. In the new generation of CNC system and servo devices, the use of "evolutionary computation" (Evolutionary Computation), "Fuzzy Systems" (Fuzzy System) and "neural networks" (Neural Network) and other three new control mechanism, the performance greatly increased. This high-performance intelligent CNC system not only has the automatic programming, feedforward control, adaptive cutting, self-generating process parameters, motion parameters of dynamic compensation and other functions, more features are taken into account operational factors used in the very present friendly interface.The current principle of fuzzy control systems, and CNC EDM with aself-learning, self-established mathematical model, high-performanceself-tuning parameters of the servo drive CNC machine tools and existing products in the market with a strong competitive edge.2. Current Situation and Development of numerical control technology gap China's CNC technology, in the "Eighth Five-Year" key in order to seize the opportunity to own the copyright for the proposed target to platform-based development strategy, but also in the research process, aiming or adjustment to the development of PC-based route , and thus the formation of two platforms, developed four basic systems, central China and the ChineseI-I-NC-specific template is embedded into a single general-purpose PC NC system bodies, space and the blue sky I-I-is embedded in the PC, being composed of CNC multi-machine CNC system, the formation of the typical structure of front, the domestic unit also has developed other open architecture system.However, in general terms, but only at the initial stage, although different systems direction to the PC platform, but in the concrete implementation of the development there are still some problems. The biggest problem that is open enough, lack of development environment and support measures, as a user easily to the secondary development of the degree of openness is far from being reached, but has considerable technical force of the developer to use, and as able to spread to the general extent of users is not enough.Design by PC-NC system makes CNC's focus from hardware to software, to eliminate the development of the CNC hardware "bottlenecks", which could accelerate the production of useful products. And PC-NC, after all, so that theopen architecture CNC a big step.In the design and manufacture of CNC machine tools, China has started a modular technology, the CNC machining process parameters, tools, system optimization, intelligent adaptive control have been studied, the intelligent control of it lay the foundation for further study, But the work is only the beginning, still in the "fifth" during a series of research and development work, tracking the world's digital technology, to promote the development of numerical control industry.Third, the "fifth" major research objectives and1. TargetIn order to further improve China's CNC technology, CNC machine tools industry, the Chinese can get a place in the international competition, China's development strategy of numerical control technology, in conjunction with the characteristics of China's economic development, first with "open", "intelligent" features CNC technology for innovative research, to focus on CNC turning, milling, grinding and processing power on the basis of advanced manufacturing technologies and processes, and then develop a generation of "open", "intelligent" CNC lathes, CNC milling machine (including the processing center) and CNC EDM products.2. Main content①Development of a new generation of open CNC system. Construction of open CNC system, interface and protocol research, including research systems, subsystems and functional modules hierarchical control structure, open CNC system interface and the Protocol.②a new generation of intelligent CNC system. Developed and worked out for turning, milling, machining centers, electrical generation of intelligent processing, and other basic computer numerical control system and the corresponding intelligent programming system. Including research and development of intelligent CNC system hardware, software specification and implementation in the main production base of CNC; development of two common systems (turning, machining centers) three applications (turning centers, five-sided machining centers, intelligent power processing ); intelligent programming system.③spindle and servo-drive a new generation of innovative research and development work out the corresponding high-performance servo drives and motors, including self-learning, self-tuning parameters, all-digital, low-cost type of linear motor and drive.④Development of efficient numerical control equipment. According to the principles of modular design, developed a highly efficient processing unit, developed a highly efficient CNC milling machine, crankshaft grinder, laser forming, CNC machining centers and integrated high-speed engraving and milling machines and other highly efficient CNC machine tools, and furtherdeveloped the idea and design platform for intelligent and efficient processing unit robot flexible manufacturing cell.⑤common basis for a new generation of flexible manufacturing equipment, technology and research. Various types of CNC machine tools including the new module design, reliability, design, mechanical design optimization of structural characteristics, computer-aided industrial design, new materials and a sense of control compensation, integrated precision contour compensation technology, high-speed high-precision axis unit, tool and integrated tool system, handling and transmission, cooling and protective, functional integration, a sense of control of integrated manufacturing and processing technologies.⑥machining theory and method of flexible automation. Including the commercialization of flexible manufacturing cell, quasi-practical flexible manufacturing system, flexible multi-standard processing techniques,multi-format production unit of flexible manufacturing technology.mon basis for a new generation of flexible manufacturing equipment, technology and research. Various types of CNC machine tools including the new module design, reliability, design, mechanical design optimization of structural characteristics, computer-aided industrial design, new materials and a sense of control compensation, integrated precision contour compensation technology, high-speed high-precision axis unit, tool and integrated tool system, handling and transmission, cooling and protective, functional integration, a sense of control of integrated manufacturing and processing technologies.8.machining theory and method of flexible automation. Including the commercialization of flexible manufacturing cell, quasi-practical flexible manufacturing system, flexible multi-standard processing techniques,multi-format production unit of flexible manufacturing technology.开放式智能化数控技术一、技术概述世界各工业发达国家通过发展数控技术、建立数控机床产业,促使机械加工业跨入一个新的“现代化”的历史发展阶段,从而给国民经济的结构带来了巨大的变化。
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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,enter21alert 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. Within1991-1994years,the economic recession of the world,expensive FMS,CIMS lowers the temperature,among1995-2000years,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,areimproving 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 dispel60%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、elligent 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 productswith 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 for3-5sport coordinate axis,a common one three rectilinear motion coordinate axis and one turn the coordinate axis of sports round(turn the workingbench round),it can one is it is it finish other4Taxi processing besides installing surfaces and top surfaces to insert to install in work piece, most suitable for processing the case body work pared 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 workingbench is suitable for processing parts for the slippery one of cross,have3 rectilinear motion coordinate axis generally,can find a room for one horizontal numerical control revolving stage(the4th axle)of axle process the spiral part at workingbench.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,aerospaceindustry,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,save2times 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 workingbench,a pair of workingbench 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 risingconstantly,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 workingbench 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 to100of the above)automatically to furnished 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 partprocessing 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 difference their 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 noumenonn 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,exceed Cheng,one one hundred sheets of 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.。