先进制造技术的新发展——机械类外文文献翻译、中英文翻译
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）。
机器人技术发展中英文对照外文翻译文献
机器人技术发展中英文对照外文翻译文献(文档含英文原文和中文翻译)外文资料：RobotsFirst, I explain the background robots, robot technology development. It should be said it is a common scientific and technological development of a comprehensive results, for the socio-economic development of a significant impact on a science and technology. It attributed the development of all countries in the Second World War to strengthen the economic input on strengthening the country's economic development. But they also demand the development of the productive forces the inevitable result of human development itself is the inevitable result then with the development of humanity, people constantly discuss the natural process, in understanding and reconstructing the natural process, people need to be able to liberate a slave. So this is the slave people to be able to replace the complex and engaged in heavy manual labor, People do not realize right up to the world's understanding and transformation of this technology as well as people in the development process of an objective need.Robots are three stages of development, in other words, we are accustomed to regarding robots are divided into three categories. is a first-generation robots, also known as teach-type robot, it is through a computer, to control over one of a mechanical degrees of freedom Through teaching and information stored procedures, working hours to read out information, and then issued a directive so the robot can repeat according to the people at that time said the results show this kind of movement again, For example, the car spot welding robots, only to put this spot welding process, after teaching, and it is always a repeat of a work It has the external environment is no perception that the force manipulation of the size of the work piece there does not exist, welding 0S It does not know, then this fact from the first generation robot, it will exist this shortcoming, it in the 20th century, the late 1970s, people started to study the second-generation robot, called Robot with the feeling that This feeling with the robot is similar in function of a certain feeling, for instance, force and touch, slipping, visual, hearing and who is analogous to that with all kinds of feelings, say in a robot grasping objects, In fact, it can be the size of feeling out, it can through visual, to be able to feel and identify its shape, size, color Grasping an egg, it adopted a acumen, aware of its power and the size of the slide.Third-generation robots, we were a robotics ideal pursued by the most advanced stage, called intelligent robots, So long as tell it what to do, not how to tell it to do, it will be able to complete the campaign, thinking and perception of this man-machine communication function and function Well, this current development or relative is in a smart part of the concept and meaning But the real significance of the integrity of this intelligent robot did not actually exist, but as we continued the development of science and technology, the concept of intelligent increasingly rich, it grows ever wider connotations.Now I have a brief account of China's robot development of the basic profiles. As our country there are many other factors that problem. Our country in robotics research of the 20th century the late 1970s. At that time, we organized at the national, a Japanese industrial automation products exhibition. In this meeting, there are two products, is a CNC machine tools, an industrial robot, this time, our country's many scholars see such a direction, has begun to make a robot research But this time, are basically confined to the theory of phase .Then the real robot research, in 7500 August 5, 1995, 15 nearly 20 years of development, The most rapid development, in 1986 we established a national plan of 863 high-technology development plan, As robot technology will be an important theme of the development of The state has invested nearly Jiganyi funds begun to make a robot, We made the robot in the field quickly and rapid development.At present, units like the CAS ShenYng Institute of Automation, the original machinery, automation of the Ministry, as of Harbin Industrial University, Beijing University of Aeronautics and Astronautics, Qinghua University, Chinese Academy of Sciences, also includes automation of some units, and so on have done a very important study, also made a lot of achievements Meanwhile, in recent years, we end up in college, a lot of flats in robot research, Many graduate students and doctoral candidates are engaged in robotics research, we are more representative national study Industrial robots, underwater robots, space robots, robots in the nuclear industry are on the international level should be taking the lead .On the whole of our country Compared with developed countries, there is still a big gap, primarily manifested in the We in the robot industry, at present there is no fixed maturity product, but in theseunderwater, space, the nuclear industry, a number of special robots, we have made a lot of achievements characteristics.Now, I would like to briefly outline some of the industrial robot situation. So far, the industrial robot is the most mature and widely used category of a robot, now the world's total sales of 1.1 million Taiwan, which is the 1999 statistics, however, 1.1 million in Taiwan have been using the equipment is 75 million, this volume is not small. Overall, the Japanese industrial robots in this one, is the first of the robots to become the Kingdom, the United States have developed rapidly. Newly installed in several areas of Taiwan, which already exceeds Japan, China has only just begun to enter the stage of industrialization, has developed a variety of industrial robot prototype and small batch has been used in production.Spot welding robot is the auto production line, improve production efficiency and raise the quality of welding car, reduce the labor intensity of a robot. It is characterized by two pairs of robots for spot welding of steel plate, bearing a great need for the welding tongs, general in dozens of kilograms or more, then its speed in meters per second a 5-2 meter of such high-speed movement. So it is generally five to six degrees of freedom, load 30 to 120 kilograms, the great space, probably expected that the work of a spherical space, a high velocity, the concept of freedom, that is to say, Movement is relatively independent of the number of components, the equivalent of our body, waist is a rotary degree of freedom We have to be able to hold his arm, Arm can be bent, then this three degrees of freedom, Meanwhile there is a wrist posture adjustment to the use of the three autonomy, the general robot has six degrees of freedom. We will be able to space the three locations, three postures, the robot fully achieved, and of course we have less than six degrees of freedom. Have more than six degrees of freedom robot, in different occasions the need to configure.The second category of service robots, with the development of industrialization, especially in the past decade, Robot development in the areas of application are continuously expanding, and now a very important characteristic, as we all know, Robot has gradually shifted from manufacturing to non-manufacturing and service industries, we are talking about the car manufacturer belonging to the manufacturing industry, However, the services sector including cleaning, refueling, rescue, rescue,relief, etc. These belong to the non-manufacturing industries and service industries, so here is compared with the industrial robot, it is a very important difference. It is primarily a mobile platform, it can move to sports, there are some arms operate, also installed some as a force sensor and visual sensors, ultrasonic ranging sensors, etc. It’s surrounding environment for the conduct of identification, to determine its campaign t o complete some work, this is service robot’s one of the basic characteristics.For example, domestic robot is mainly embodied in the example of some of the carpets and flooring it to the regular cleaning and vacuuming. The robot it is very meaningful, it has sensors, it can furniture and people can identify, It automatically according to a law put to the ground under the road all cleaned up. This is also the home of some robot performance.The medical robots, nearly five years of relatively rapid development of new application areas. If people in the course of an operation, doctors surgery, is a fatigue, and the other manually operated accuracy is limited. Some universities in Germany, which, facing the spine, lumbar disc disease, the identification, can automatically use the robot-aided positioning, operation and surgery Like the United States have been more than 1,000 cases of human eyeball robot surgery, the robot, also including remote-controlled approach, the right of such gastrointestinal surgery, we see on the television inside. a manipulator, about the thickness fingers such a manipulator, inserted through the abdominal viscera, people on the screen operating the machines hand, it also used the method of laser lesion laser treatment, this is the case, people would not have a very big damage to the human body.In reality, this right as a human liberation is a very good robots, medical robots it is very complex, while it is fully automated to complete all the work, there are difficulties, and generally are people to participate. This is America, the development of such a surgery Lin Bai an example, through the screen, through a remote control operator to control another manipulator, through the realization of the right abdominal surgery A few years ago our country the exhibition, the United States has been successful in achieving the right to the heart valve surgery and bypass surgery. This robot has in the area, caused a great sensation, but also, AESOP's surgical robot, In fact, it through some equipment to some of the lesions inspections, through amanipulator can be achieved on some parts of the operation Also including remotely operated manipulator, and many doctors are able to participate in the robot under surgery Robot doctor to include doctors with pliers, tweezers or a knife to replace the nurses, while lighting automatically to the doctor's movements linked, the doctor hands off, lighting went off, This is very good, a doctor's assistant.We regard this country excel, it should be said that the United States, Russia and France, in our nation, also to the international forefront, which is the CAS ShenYang Institute of Automation of developing successful, 6,000 meters underwater without cable autonomous underwater robot, the robot to 6,000 meters underwater, can be conducted without cable operations. His is 2000, has been obtained in our country one of the top ten scientific and technological achievements. This indicates that our country in this underwater robot, have reached the advanced international level, 863 in the current plan, the development of 7,000 meters underwater in a manned submersible to the ocean further development and operation, This is a great vote of financial and material resources.In this space robotics research has also been a lot of development. In Europe, including 16 in the United States space program, and the future of this space capsule such a scheme, One thing is for space robots, its main significance lies in the development of the universe and the benefit of mankind and the creation of new human homes, Its main function is to scientific investigation, as production and space scientific experiments, satellites and space vehicles maintenance and repair, and the construction of the space assembly. These applications, indeed necessary, for example, scientific investigation, as if to mock the ground some physical and chemical experiments do not necessarily have people sitting in the edge of space, because the space crew survival in the day the cost is nearly one million dollars. But also very dangerous, in fact, some action is very simple, through the ground, via satellite control robot, and some regularly scheduled completion of the action is actually very simple. Include the capsule as control experiments, some switches, buttons, simple flange repair maintenance, Robot can be used to be performed by robots because of a solar battery, then the robot will be able to survive, we will be able to work, We have just passed the last robot development on the application of the different areas ofapplication, and have seen the robots in industry, medical, underwater, space, mining, construction, service, entertainment and military aspects of the application .Also really see that the application is driven by the development of key technologies, a lack of demand, the robot can not, It is because people in understanding the natural transformation of the natural process, the needs of a wide range of robots, So this will promote the development of key technologies, the robot itself for the development of From another aspect, as key technology solutions, as well as the needs of the application, on the promotion of the robot itself a theme for the development of intelligent, and from teaching reappearance development of the current local perception of the second-generation robot, the ultimate goal, continuously with other disciplines and the development of advanced technology, the robot has become rich, eventually achieve such an intelligent robot mainstream.Robot is mankind's right-hand man; friendly coexistence can be a reliable friend. In future, we will see and there will be a robot space inside, as a mutual aide and friend. Robots will create the jobs issue. We believe that there would not be a "robot appointment of workers being laid off" situation, because people with the development of society, In fact the people from the heavy physical and dangerous environment liberated, so that people have a better position to work, to create a better spiritual wealth and cultural wealth.译文：机器人首先我介绍一下机器人产生的背景，机器人技术的发展，它应该说是一个科学技术发展共同的一个综合性的结果，同时，为社会经济发展产生了一个重大影响的一门科学技术，它的发展归功于在第二次世界大战中各国加强了经济的投入，就加强了本国的经济的发展。
机械类外文文献及翻译
机械类外文文献及翻译(文档含中英文对照即英文原文和中文翻译)原文：GEAR AND SHAFT INTRODUCTIONAbstract:The important position of the wheel gear and shaft can't falter in traditional machine and modern machines.The wheel gear and shafts mainly install the direction that delivers the dint at the principal axis box. The passing to process to make them can is divided into many model numbers, using for many situations respectively. So we must be the multilayers to the understanding of the wheel gear and shaft in many ways .Key words: Wheel gear; ShaftIn the force analysis of spur gears, the forces are assumed to act in a single plane. We shall study gears in which the forces have three dimensions. The reason for this, in the case of helical gears, is that the teeth are not parallel to the axis of rotation. And in the case ofbevel gears, the rotational axes are not parallel to each other. There are also other reasons, as we shall learn.Helical gears are used to transmit motion between parallel shafts. The helix angle is the same on each gear, but one gear must have a right-hand helix and the other a left-hand helix. The shape of the tooth is an involute helicoid. If a piece of paper cut in the shape of a parallelogram is wrapped around a cylinder, the angular edge of the paper becomes a helix. If we unwind this paper, each point on the angular edge generates an involute curve. The surface obtained when every point on the edge generates an involute is called an involute helicoid.The initial contact of spur-gear teeth is a line extending all the way across the face of the tooth. The initial contact of helical gear teeth is a point, which changes into a line as the teeth come into more engagement. In spur gears the line of contact is parallel to the axis of the rotation; in helical gears, the line is diagonal across the face of the tooth. It is this gradual of the teeth and the smooth transfer of load from one tooth to another, which give helical gears the ability to transmit heavy loads at high speeds. Helical gears subject the shaft bearings to both radial and thrust loads. When the thrust loads become high or are objectionable for other reasons, it may be desirable to use double helical gears. A double helical gear (herringbone) is equivalent to two helical gears of opposite hand, mounted side by side on the same shaft. They develop opposite thrust reactions and thus cancel out the thrust load. When two or more single helical gears are mounted on the same shaft, the hand of the gears should be selected so as to produce the minimum thrust load.Crossed-helical, or spiral, gears are those in which the shaft centerlines are neither parallel nor intersecting. The teeth of crossed-helical fears have point contact with each other, which changes to line contact as the gears wear in. For this reason they will carry out very small loads and are mainly for instrumental applications, and are definitely not recommended for use in the transmission of power. There is on difference between a crossed heli : cal gear and a helical gear until they are mounted in mesh with each other. They are manufactured in the same way. A pair of meshed crossed helical gears usually have the same hand; that is ,a right-hand driver goes with a right-hand driven. In the design of crossed-helical gears, the minimum sliding velocity is obtained when the helix angle areequal. However, when the helix angle are not equal, the gear with the larger helix angle should be used as the driver if both gears have the same hand.Worm gears are similar to crossed helical gears. The pinion or worm has a small number of teeth, usually one to four, and since they completely wrap around the pitch cylinder they are called threads. Its mating gear is called a worm gear, which is not a true helical gear. A worm and worm gear are used to provide a high angular-velocity reduction between nonintersecting shafts which are usually at right angle. The worm gear is not a helical gear because its face is made concave to fit the curvature of the worm in order to provide line contact instead of point contact. However, a disadvantage of worm gearing is the high sliding velocities across the teeth, the same as with crossed helical gears.Worm gearing are either single or double enveloping. A single-enveloping gearing is onein which the gear wraps around or partially encloses the worm.. A gearing in which each element partially encloses the other is, of course, a double-enveloping worm gearing. The important difference between the two is that area contact exists between the teeth of double-enveloping gears while only line contact between those of single-enveloping gears. The worm and worm gear of a set have the same hand of helix as for crossed helical gears, but the helix angles are usually quite different. The helix angle on the worm is generally quite large, and that on the gear very small. Because of this, it is usual to specify the lead angle on the worm, which is the complement of the worm helix angle, and the helix angle on the gear; the two angles are equal for a 0-deg. Shaft angle.When gears are to be used to transmit motion between intersecting shaft, some of bevel gear is required. Although bevel gear are usually made for a shaft angle of 0 deg. They may be produced for almost any shaft angle. The teeth may be cast, milled, or generated. Only the generated teeth may be classed as accurate. In a typical bevel gear mounting, one of the gear is often mounted outboard of the bearing. This means that shaft deflection can be more pronounced and have a greater effect on the contact of teeth. Another difficulty, which occurs in predicting the stress in bevel-gear teeth, is the fact the teeth are tapered.Straight bevel gears are easy to design and simple to manufacture and give very good results in service if they are mounted accurately and positively. As in the case of squr gears, however, they become noisy at higher values of the pitch-line velocity. In these cases it is often go : od design practice to go to the spiral bevel gear, which is the bevel counterpart of thehelical gear. As in the case of helical gears, spiral bevel gears give a much smoother tooth action than straight bevel gears, and hence are useful where high speed are encountered.It is frequently desirable, as in the case of automotive differential applications, to have gearing similar to bevel gears but with the shaft offset. Such gears are called hypoid gears because their pitch surfaces are hyperboloids of revolution. The tooth action between such gears is a combination of rolling and sliding along a straight line and has much in common with that of worm gears.A shaft is a rotating or stationary member, usually of circular cross section, having mounted upon it such elementsas gears, pulleys, flywheels, cranks, sprockets, and other power-transmission elements. Shaft may be subjected to bending, tension, compression, or torsional loads, acting singly or in combination with one another. When they are combined, one may expect to find both static and fatigue strength to be important design considerations, since a single shaft may be subjected to static stresses, completely reversed, and repeated stresses, all acting at the same time.The word “shaft” covers numerous v ariations, such as axles and spindles. Anaxle is a shaft, wither stationary or rotating, nor subjected to torsion load. A shirt rotating shaft is often called a spindle.When either the lateral or the torsional deflection of a shaft must be held to close limits, the shaft must be sized on the basis of deflection before analyzing the stresses. The reason for this is that, if the shaft is made stiff enough so that the deflection is not too large, it is probable that the resulting stresses will be safe. But by no means should the designer assume that they are safe; it is almost always necessary to calculate them so that he knows they are within acceptable limits. Whenever possible, the power-transmission elements, such as gears or pullets, should be located close to the supporting bearings, This reduces the bending moment, and hence the deflection and bending stress.Although the von Mises-Hencky-Goodman method is difficult to use in design of shaft, it probably comes closest to predicting actual failure. Thus it is a good way of checking a shaft that has already been designed or of discovering why a particular shaft has failed in service. Furthermore, there are a considerable number of shaft-design problems in which the dimension are pretty well limited by other considerations, such as rigidity, and it is only necessary for the designer to discover something about the fillet sizes, heat-treatment,and surface finish and whether or not shot peening is necessary in order to achieve the required life and reliability.Because of the similarity of their functions, clutches and brakes are treated together. In a simplified dynamic representation of a friction clutch, or brake, two in : ertias I and I traveling at the respective angular velocities W and W, one of which may be zero in the case of brake, are to be brought to the same speed by engaging the clutch or brake. Slippage occurs because the two elements are running at different speeds and energy is dissipated during actuation, resulting in a temperature rise. In analyzing the performance of these devices we shall be interested in the actuating force, the torque transmitted, the energy loss and the temperature rise. The torque transmitted is related to the actuating force, the coefficient of friction, and the geometry of the clutch or brake. This is problem in static, which will have to be studied separately for eath geometric configuration. However, temperature rise is related to energy loss and can be studied without regard to the type of brake or clutch because the geometry of interest is the heat-dissipating surfaces. The various types of clutches and brakes may be classified as fllows:. Rim type with internally expanding shoes. Rim type with externally contracting shoes. Band type. Disk or axial type. Cone type. Miscellaneous typeThe analysis of all type of friction clutches and brakes use the same general procedure. The following step are necessary:. Assume or determine the distribution of pressure on the frictional surfaces.. Find a relation between the maximum pressure and the pressure at any point. Apply the condition of statical equilibrium to find (a) the actuating force, (b) the torque, and (c) the support reactions.Miscellaneous clutches include several types, such as the positive-contact clutches, overload-release clutches, overrunning clutches, magnetic fluid clutches, and others.A positive-contact clutch consists of a shift lever and two jaws. The greatest differences between the various types of positive clutches are concerned with the design of the jaws. To provide a longer period of time for shift action during engagement, the jaws may be ratchet-shaped, or gear-tooth-shaped. Sometimes a great many teeth or jaws are used, and they may be cut either circumferentially, so that they engage by cylindrical mating, or on the faces of the mating elements.Although positive clutches are not used to the extent of the frictional-contact type, they do have important applications where synchronous operation is required.Devices such as linear drives or motor-operated screw drivers must run to definite limit and then come to a stop. An overload-release type of clutch is required for these applications. These clutches are usually spring-loaded so as to release at a predetermined toque. The clicking sound which is heard when the overload point is reached is considered to be a desirable signal.An overrunning clutch or coupling permits the driven member of a machine to “freewheel” or “overrun” bec ause the driver is stopped or because another source of power increase the speed of the driven. This : type of clutch usually uses rollers or balls mounted between an outer sleeve and an inner member having flats machined around the periphery. Driving action is obtained by wedging the rollers between the sleeve and the flats. The clutch is therefore equivalent to a pawl and ratchet with an infinite number of teeth.Magnetic fluid clutch or brake is a relatively new development which has two parallel magnetic plates. Between these plates is a lubricated magnetic powder mixture. An electromagnetic coil is inserted somewhere in the magnetic circuit. By varying the excitation to this coil, the shearing strength of the magnetic fluid mixture may be accurately controlled. Thus any condition from a full slip to a frozen lockup may be obtained.齿轮和轴的介绍摘要:在传统机械和现代机械中齿轮和轴的重要地位是不可动摇的。
机械加工外文翻译文献
中英文对照外文翻译文献(文档含英文原文和中文翻译)原文：Selection of optimum tool geometry and cutting conditionsusing a surface roughness prediction model for end milling Abstract Influence of tool geometry on the quality of surface produced is well known and hence any attempt to assess the performance of end milling should include the tool geometry. In the present work, experimental studies have been conducted to see the effect of tool geometry (radial rake angle and nose radius) and cutting conditions (cutting speed and feed rate) on the machining performance during end milling of medium carbon steel. The first and second order mathematical models, in terms of machining parameters, were developed for surface roughness prediction using response surface methodology (RSM) on the basis of experimental results. The model selected for optimization has been validated with the Chi square test. The significance of these parameters on surface roughness has been established with analysis of variance. An attempthas also been made to optimize the surface roughness prediction model using genetic algorithms (GA). The GA program gives minimum values of surface roughness and their respective optimal conditions.1 IntroductionEnd milling is one of the most commonly used metal removal operations in industry because of its ability to remove material faster giving reasonably good surface quality. It is used in a variety of manufacturing industries including aerospace and automotive sectors, where quality is an important factor in the production of slots, pockets, precision moulds and dies. Greater attention is given to dimensional accuracy and surface roughness of products by the industry these days. Moreover, surface finish influences mechanical properties such as fatigue behaviour, wear, corrosion, lubrication and electrical conductivity. Thus, measuring and characterizing surface finish can be considered for predicting machining performance.Surface finish resulting from turning operations has traditionally received considerable research attention, where as that of machining processes using multipoint cutters, requires attention by researchers. As these processes involve large number of parameters, it would be difficult to correlate surface finish with other parameters just by conducting experiments. Modelling helps to understand this kind of process better. Though some amount of work has been carried out to develop surface finish prediction models in the past, the effect of tool geometry has received little attention. However, the radial rake angle has a major affect on the power consumption apart from tangential and radial forces. It also influences chip curling and modifies chip flow direction. In addition to this, researchers [1] have also observed that the nose radius plays a significant role in affecting the surface finish. Therefore the development of a good model should involve the radial rake angle and nose radius along with other relevant factors.Establishment of efficient machining parameters has been a problem that has confronted manufacturing industries for nearly a century, and is still the subject of many studies. Obtaining optimum machining parameters is of great concern in manufacturing industries, where the economy of machining operation plays a key role in the competitive market. In material removal processes, an improper selection of cutting conditions cause surfaces with high roughness and dimensional errors, and it is even possible that dynamic phenomena due to auto excited vibrations may set in [2]. In view of the significant role that the milling operation plays in today‟s manufacturing world, there is a need to optimize the machining parameters for this operation. So, an effort has been made in this paper to see the influence of tool geometry(radial rake angle and nose radius) and cutting conditions(cutting speed and feed rate) on the surfacefinish produced during end milling of medium carbon steel. The experimental results of this work will be used to relate cutting speed, feed rate, radial rake angle and nose radius with the machining response i.e. surface roughness by modelling. The mathematical models thus developed are further utilized to find the optimum process parameters using genetic algorithms.2 ReviewProcess modelling and optimization are two important issues in manufacturing. The manufacturing processes are characterized by a multiplicity of dynamically interacting process variables. Surface finish has been an important factor of machining in predicting performance of any machining operation. In order to develop and optimize a surface roughness model, it is essential to understand the current status of work in this area.Davis et al. [3] have investigated the cutting performance of five end mills having various helix angles. Cutting tests were performed on aluminium alloy L 65 for three milling processes (face, slot and side), in which cutting force, surface roughness and concavity of a machined plane surface were measured. The central composite design was used to decide on the number of experiments to be conducted. The cutting performance of the end mills was assessed using variance analysis. The affects of spindle speed, depth of cut and feed rate on the cutting force and surface roughness were studied. The investigation showed that end mills with left hand helix angles are generally less cost effective than those with right hand helix angles. There is no significant difference between up milling and down milling with regard tothe cutting force, although the difference between them regarding the surface roughness was large. Bayoumi et al.[4] have studied the affect of the tool rotation angle, feed rate and cutting speed on the mechanistic process parameters (pressure, friction parameter) for end milling operation with three commercially available workpiece materials, 11 L 17 free machining steel, 62- 35-3 free machining brass and 2024 aluminium using a single fluted HSS milling cutter. It has been found that pressure and friction act on the chip – tool interface decrease with the increase of feed rate and with the decrease of the flow angle, while the cutting speed has a negligible effect on some of the material dependent parameters. Process parameters are summarized into empirical equations as functions of feed rate and tool rotation angle for each work material. However, researchers have not taken into account the effects of cutting conditions and tool geometry simultaneously; besides these studies have not considered the optimization of the cutting process.As end milling is a process which involves a large number f parameters, combined influence of the significant parameters an only be obtained by modelling. Mansour and Abdallaet al. [5] have developed a surface roughness model for the end milling of EN32M (a semi-free cutting carbon case hardening steel with improved merchantability). The mathematical modelhas been developed in terms of cutting speed, feed rate and axial depth of cut. The affect of these parameters on the surface roughness has been carried out using response surface methodology (RSM). A first order equation covering the speed range of 30–35 m/min and a second order equation covering the speed range of 24–38 m/min were developed under dry machining conditions. Alauddin et al. [6] developed a surface roughness model using RSM for the end milling of 190 BHN steel. First and second order models were constructed along with contour graphs for the selection of the proper combination of cutting speed and feed to increase the metal removal rate without sacrificing surface quality. Hasmi et al. [7] also used the RSM model for assessing the influence of the workpiece material on the surface roughness of the machined surfaces. The model was developed for milling operation by conducting experiments on steel specimens. The expression shows, the relationship between the surface roughness and the various parameters; namely, the cutting speed, feed and depth of cut. The above models have not considered the affect of tool geometry on surface roughness.Since the turn of the century quite a large number of attempts have been made to find optimum values of machining parameters. Uses of many methods have been reported in the literature to solve optimization problems for machining parameters. Jain and Jain [8] have used neural networks for modeling and optimizing the machining conditions. The results have been validated by comparing the optimized machining conditions obtained using genetic algorithms. Suresh et al. [9] have developed a surface roughness prediction model for turning mild steel using a response surface methodology to produce the factor affects of the individual process parameters. They have also optimized the turning process using the surface roughness prediction model as the objective function. Considering the above, an attempt has been made in this work to develop a surface roughness model with tool geometry and cutting conditions on the basis of experimental results and then optimize it for the selection of these parameters within the given constraints in the end milling operation.3 MethodologyIn this work, mathematical models have been developed using experimental results with the help of response surface methodolog y. The purpose of developing mathematical models relating the machining responses and their factors is to facilitate the optimization of the machining process. This mathematical model has been used as an objective function and the optimization was carried out with the help of genetic algorithms.3.1 Mathematical formulationResponse surface methodology(RSM) is a combination of mathematical and statisticaltechniques useful for modelling and analyzing the problems in which several independent variables influence a dependent variable or response. The mathematical models commonly used are represented by:where Y is the machining response, ϕ is the response function and S, f , α, r are milling variables and ∈is the error which is normally distributed about the observed response Y with zero mean.The relationship between surface roughness and other independent variables can be represented as follows，where C is a constant and a, b, c and d are exponents.To facilitate the determination of constants and exponents, this mathematical model will have to be linearized by performing a logarithmic transformation as follows:The constants and exponents C, a, b, c and d can be determined by the method of least squares. The first order linear model, developed from the above functional relationship using least squares method, can be represented as follows:where Y1 is the estimated response based on the first-order equation, Y is the measured surface roughness on a logarithmic scale, x0 = 1 (dummy variable), x1, x2, x3 and x4 are logarithmic transformations of cutting speed, feed rate, radial rake angle and nose radius respectively, ∈is the experimental error and b values are the estimates of corresponding parameters.The general second order polynomial response is as given below:where Y2 is the estimated response based on the second order equation. The parameters, i.e. b0, b1, b2, b3, b4, b12, b23, b14, etc. are to be estimated by the method of least squares. Validity of the selected model used for optimizing the process parameters has been tested with the help of statistical tests, such as F-test, chi square test, etc. [10].3.2 Optimization using genetic algorithmsMost of the researchers have used traditional optimization techniques for solving machining problems. The traditional methods of optimization and search do not fare well over a broad spectrum of problem domains. Traditional techniques are not efficient when the practical search space is too large. These algorithms are not robust. They are inclined to obtain a local optimal solution. Numerous constraints and number of passes make the machining optimization problem more complicated. So, it was decided to employ genetic algorithms as an optimization technique. GA come under the class of non-traditional search and optimization techniques. GA are different from traditional optimization techniques in the following ways:1.GA work with a coding of the parameter set, not the parameter themselves.2.GA search from a population of points and not a single point.3.GA use information of fitness function, not derivatives or other auxiliary knowledge.4.GA use probabilistic transition rules not deterministic rules.5.It is very likely that the expected GA solution will be the global solution.Genetic algorithms (GA) form a class of adaptive heuristics based on principles derived from the dynamics of natural population genetics. The searching process simulates the natural evaluation of biological creatures and turns out to be an intelligent exploitation of a random search. The mechanics of a GA is simple, involving copying of binary strings. Simplicity of operation and computational efficiency are the two main attractions of the genetic algorithmic approach. The computations are carried out in three stages to get a result in one generation or iteration. The three stages are reproduction, crossover and mutation.In order to use GA to solve any problem, the variable is typically encoded into a string (binary coding) or chromosome structure which represents a possible solution to the given problem. GA begin with a population of strings (individuals) created at random. The fitness of each individual string is evaluated with respect to the given objective function. Then this initial population is operated on by three main operators – reproduction cross over and mutation– to create, hopefully, a better population. Highly fit individuals or solutions are given the opportunity to reproduce by exchanging pieces of their genetic information, in the crossover procedure, with other highly fit individuals. This produces new “offspring” solutions, which share some characteristics taken from both the parents. Mutation is often applied after crossover by altering some genes (i.e. bits) in the offspring. The offspring can either replace the whole population (generational approach) or replace less fit individuals (steady state approach). This new population is further evaluated and tested for some termination criteria. The reproduction-cross over mutation- evaluation cycle is repeated until the termination criteria are met.4 Experimental detailsFor developing models on the basis of experimental data, careful planning of experimentation is essential. The factors considered for experimentation and analysis were cutting speed, feed rate, radial rake angle and nose radius.4.1 Experimental designThe design of experimentation has a major affect on the number of experiments needed. Therefore it is essential to have a well designed set of experiments. The range of values of each factor was set at three different levels, namely low, medium and high as shown in Table 1. Basedon this, a total number of 81 experiments (full factorial design), each having a combination of different levels of factors, as shown in Table 2, were carried out.The variables were coded by taking into account the capacity and limiting cutting conditions of the milling machine. The coded values of variables, to be used in Eqs. 3 and 4, were obtained from the following transforming equations:where x1 is the coded value of cutting speed (S), x2 is the coded value of the feed rate ( f ), x3 is the coded value of radial rake angle(α) and x4 is the coded value of nose radius (r).4.2 ExperimentationA high precision …Rambaudi Rammatic 500‟ CNC milling machine, with a vertical milling head, was used for experimentation. The control system is a CNC FIDIA-12 compact. The cutting tools, used for the experimentation, were solid coated carbide end mill cutters of different radial rake angles and nose radii (WIDIA: DIA20 X FL38 X OAL 102 MM). The tools are coated with TiAlN coating. The hardness, density and transverse rupture strength are 1570 HV 30, 14.5 gm/cm3 and 3800 N/mm2 respectively.AISI 1045 steel specimens of 100×75 mm and 20 mm thickness were used in the present study. All the specimens were annealed, by holding them at 850 ◦C for one hour and then cooling them in a furnace. The chemical analysis of specimens is presented in Table 3. The hardness of the workpiece material is 170 BHN. All the experiments were carried out at a constant axial depth of cut of 20 mm and a radial depth of cut of 1 mm. The surface roughness (response) was measured with Talysurf-6 at a 0.8 mm cut-off value. An average of four measurements was used as a response value.5 Results and discussionThe influences of cutting speed, feed rate, radial rake angle and nose radius have been assessed by conducting experiments. The variation of machining response with respect to the variables was shown graphically in Fig. 1. It is seen from these figures that of the four dependent parameters, radial rake angle has definite influence on the roughness of the surface machined using an end mill cutter. It is felt that the prominent influence of radial rake angle on the surface generation could be due to the fact that any change in the radial rake angle changes the sharpness of the cutting edge on the periphery, i.e changes the contact length between the chip and workpiece surface. Also it is evident from the plots that as the radial rake angle changes from 4◦to 16◦, the surface roughness decreases and then increases. Therefore, it may be concluded here that the radial rake angle in the range of 4◦to 10◦would give a better surface finish. Figure 1also shows that the surface roughness decreases first and then increases with the increase in the nose radius. This shows that there is a scope for finding the optimum value of the radial rake angle and nose radius for obtaining the best possible quality of the surface. It was also found that the surface roughness decreases with an increase in cutting speed and increases as feed rate increases. It could also be observed that the surface roughness was a minimum at the 250 m/min speed, 200 mm/min feed rate, 10◦radial rake angle and 0.8 mm nose radius. In order to understand the process better, the experimental results can be used to develop mathematical models using RSM. In this work, a commercially available mathematical software package (MATLAB) was used for the computation of the regression of constants and exponents.5.1 The roughness modelUsing experimental results, empirical equations have been obtained to estimate surface roughness with the significant parameters considered for the experimentation i.e. cutting speed, feed rate, radial rake angle and nose radius. The first order model obtained from the above functional relationship using the RSM method is as follows:The transformed equation of surface roughness prediction is as follows:Equation 10 is derived from Eq. 9 by substituting the coded values of x1, x2, x3 and x4 in terms of ln s, ln f , lnαand ln r. The analysis of the variance (ANOV A) and the F-ratio test have been performed to justify the accuracy of the fit for the mathematical model. Since the calculated values of the F-ratio are less than the standard values of the F-ratio for surface roughness as shown in Table 4, the model is adequate at 99% confidence level to represent the relationship between the machining response and the considered machining parameters of the end milling process.The multiple regression coefficient of the first order model was found to be 0.5839. This shows that the first order model can explain the variation in surface roughness to the extent of 58.39%. As the first order model has low predictability, the second order model has been developed to see whether it can represent better or not.The second order surface roughness model thus developed is as given below:where Y2 is the estimated response of the surface roughness on a logarithmic scale, x1, x2, x3 and x4 are the logarithmic transformation of speed, feed, radial rake angle and nose radius. The data of analysis of variance for the second order surface roughness model is shown in Table 5.Since F cal is greater than F0.01, there is a definite relationship between the responsevariable and independent variable at 99% confidence level. The multiple regression coefficient of the second order model was found to be 0.9596. On the basis of the multiple regression coefficient (R2), it can be concluded that the second order model was adequate to represent this process. Hence the second order model was considered as an objective function for optimization using genetic algorithms. This second order model was also validated using the chi square test. The calculated chi square value of the model was 0.1493 and them tabulated value at χ2 0.005 is 52.34, as shown in Table 6, which indicates that 99.5% of the variability in surface roughness was explained by this model.Using the second order model, the surface roughness of the components produced by end milling can be estimated with reasonable accuracy. This model would be optimized using genetic algorithms (GA).5.2 The optimization of end millingOptimization of machining parameters not only increases the utility for machining economics, but also the product quality toa great extent. In this context an effort has been made to estimate the optimum tool geometry and machining conditions to produce the best possible surface quality within the constraints.The constrained optimization problem is stated as follows: Minimize Ra using the model given here:where xil and xiu are the upper and lower bounds of process variables xi and x1, x2, x3, x4 are logarithmic transformation of cutting speed, feed, radial rake angle and nose radius.The GA code was developed using MATLAB. This approach makes a binary coding system to represent the variables cutting speed (S), feed rate ( f ), radial rake angle (α) and nose radius (r), i.e. each of these variables is represented by a ten bit binary equivalent, limiting the total string length to 40. It is known as a chromosome. The variables are represented as genes (substrings) in the chromosome. The randomly generated 20 such chromosomes (population size is 20), fulfilling the constraints on the variables, are taken in each generation. The first generation is called the initial population. Once the coding of the variables has been done, then the actual decoded values for the variables are estimated using the following formula: where xi is the actual decoded value of the cutting speed, feed rate, radial rake angle and nose radius, x(L) i is the lower limit and x(U) i is the upper limit and li is the substring length, which is equal to ten in this case.Using the present generation of 20 chromosomes, fitness values are calculated by the following transformation:where f(x) is the fitness function and Ra is the objective function.Out of these 20 fitness values, four are chosen using the roulette-wheel selection scheme. The chromosomes corresponding to these four fitness values are taken as parents. Then the crossover and mutation reproduction methods are applied to generate 20 new chromosomes for the next generation. This processof generating the new population from the old population is called one generation. Many such generations are run till the maximum number of generations is met or the average of four selected fitness values in each generation becomes steady. This ensures that the optimization of all the variables (cutting speed, feed rate, radial rake angle and nose radius) is carried out simultaneously. The final statistics are displayed at the end of all iterations. In order to optimize the present problem using GA, the following parameters have been selected to obtain the best possible solution with the least computational effort: Table 7 shows some of the minimum values of the surface roughness predicted by the GA program with respect to input machining ranges, and Table 8 shows the optimum machining conditions for the corresponding minimum values of the surface roughness shown in Table 7. The MRR given in Table 8 was calculated bywhere f is the table feed (mm/min), aa is the axial depth of cut (20 mm) and ar is the radial depth of cut (1 mm).It can be concluded from the optimization results of the GA program that it is possible to select a combination of cutting speed, feed rate, radial rake angle and nose radius for achieving the best possible surface finish giving a reasonably good material removal rate. This GA program provides optimum machining conditions for the corresponding given minimum values of the surface roughness. The application of the genetic algorithmic approach to obtain optimal machining conditions will be quite useful at the computer aided process planning (CAPP) stage in the production of high quality goods with tight tolerances by a variety of machining operations, and in the adaptive control of automated machine tools. With the known boundaries of surface roughness and machining conditions, machining could be performed with a relatively high rate of success with the selected machining conditions.6 ConclusionsThe investigations of this study indicate that the parameters cutting speed, feed, radial rake angle and nose radius are the primary actors influencing the surface roughness of medium carbon steel uring end milling. The approach presented in this paper provides n impetus to develop analytical models, based on experimental results for obtaining a surface roughness model using the response surface methodology. By incorporating the cutter geometry in the model, the validity of the model has been enhanced. The optimization of this model using geneticalgorithms has resulted in a fairly useful method of obtaining machining parameters in order to obtain the best possible surface quality.翻译：选择最佳工具，几何形状和切削条件利用表面粗糙度预测模型端铣摘要：刀具几何形状对工件表面质量产生的影响是人所共知的，因此，任何成型面端铣设计应包括刀具的几何形状。
先进制造技术的新发展中英文翻译、外文翻译、外文文献翻译
外文原文：The new advanced manufacturing technology developmentAbstract : This paper has presented the problems facing today's manufacturing technology, advanced manufacturing discussed in the forefront of science, and a vision for the future development of advanced manufacturing technology.Keyword：Advanced manufacturing technologies; Frontier science; Applications prospectsModern manufacturing is an important pillar of the national economy and overall national strength and its GDP accounted for a general national GDP 20%~55%. In the composition of a country's business productivity, manufacturing technology around 60% of the general role. Experts believe that the various countries in the world economic competition, mainly manufacturing technology competition. Their competitiveness in the production of the final product market share. With the rapid economic and technological development and customer needs and the changing market environment, this competition is becoming increasingly fierce, and that Governments attach great importance to the advanced manufacturing technology research.1 .Current manufacturing science to solve problemsManufacturing science to solve the current problems focused on the following aspects :(1) Manufacturing systems is a complex systems, and manufacturing systems to meet both agility, rapid response and rapid reorganization of the capacity to learn from the information science, life science and social science interdisciplinary research, and explore new manufacturing system architecture, manufacturing models and manufacturing systems effective operational mechanism. Manufacturing systems optimized organizational structure and good performance is manufacturing systemmodelling, simulation and optimization of the main objectives. Manufacturing system architecture not only to create new enterprises both agility and responsiveness to the needs and the ability to reorganize significance, but also for the soft production equipment manufacturing enterprises bottom reorganization and dynamic capacity to set higher demands. Biological manufacturing outlook increasingly being introduced to the system to meet new demands manufacturing systems.(2) The rapid rise in support of manufacturing, geometric knowledge sharing has become a modern manufacturing constraints, product development and manufacturing technologies of the key issues. For example, in computer-aided design and manufacturing (CAD/CAM) integration, coordinates measurements (CMM) and robotics fields, in 3D real space (3-Real Space), there are a lot of geometric algorithm design and analysis, especially the geometric said, geometric calculation and geometric reasoning; In measurement and robot path planning and parts search spaces (such as Localization), the existence of space C- interspace (configuration space Configuration Space) geometric calculation and geometric reasoning; Objects in operation (rescue, paying and assembly, etc.) means paying more description and robot planning, campaign planning and assembly operations planning is needed in the types of space (Screw Space) geometric reasoning. Manufacturing process of physical and geometric mechanics phenomenon of scientific research to create a geometric calculation and geometric reasoning, and other aspects of the research topic, the theory pending further breakthrough, the new one door disciplines -- computer geometric are being increasingly broad and in-depth study.(3) In the modern manufacturing process, information not only manufacturing industries have become dominated the decisive factor, but also the most active ones. Manufacturing information systems to improve throughput of modern manufacturing has become a focus of scientific development. The manufacturing information system organization and structure required to create information access, integration and integration show three-dimensional in nature, measuring the multidimensional nature of the information, and information organizations nature. Information structure models in the manufacturing, manufacturing information consistency constraint, andthe dissemination of data processing and the manufacture of enormous knowledge base management, and other areas, there is a need to further breakthroughs.(4) The calculation of the wisdom of artificial intelligence tools and methods in the manufacture of a wide range of applications for manufacturing smart development. Category based on the calculation of biological evolution algorithms smart tools, including activation issues optimize GPS technology portfolio by growing concern is in the manufacture of the complete portfolio optimization problems combined speed and precision of GPS issues both in size constraints. Manufacturing wisdom manifested in the following aspects : wisdom activation, wisdom design, intelligent processing, robotics, intelligent control, intelligent process planning, smart diagnostic, and other aspects. These innovative products are the key theoretical issues, but also by creating a door for a science skills in the important basic issues. The focus in these issues, we can form the basis of product innovation research system.2. Modern mechanical engineering at the frontiers of scienceCross-integration between the different science will produce new scientific gathering, economic development and social progress of science and technology created new demands and expectations, thus creating a frontier science. Frontier science is settled and unsettled issues between the scientific community. Frontier science, with a clear domain, and dynamic character of the area. Works frontier science from the general basic science is an important characteristic of the actual works, it covers the key emerging science and technology issues. Ultrasonic electrical, ultra-high-speed machines, green design and manufacturing, and other fields, and has done a lot of research work, but innovation is the key question is not clear mechanical science. Large complex mechanical system design and performance optimization of product innovation design, smart structures and systems, intelligent robots and their dynamics, nano Mocaxue, manufacturing process 3D numerical simulations and physical simulation, precision and ultra-fine processing technology key basis, about 10 mega large and sophisticated equipment design and manufacturing base, virtual manufacturing and virtual instruments, nanometer measurement and instrumentation, parallel connection axis machine tools, and although the field ofmicro-electromechanical systems have done a lot of research, but there are still many key science and technology issues to be resolved. Information science, nano science, materials science, life science, management science and manufacturing science of the 21st century will be to change the mainstream science, and the resulting high-tech industry will change the face of the world. Therefore, the above areas of cross-development manufacturing systems and manufacturing informatics, nano manufacturing machinery and nano science, better machinery and better manufacturing science, management science and manufacturing systems will be critical to the 21st century mechanical engineering science is important frontier science.2.1 Manufacturing science and information science cross -- manufacturing informaticsMechanical and electrical products, chemical raw materials in the information. Many modern value added products primarily reflected in the information. Thus the manufacturing process for the acquisition and application of information is very important. Information science and technology is to create an important symbol of globalization and modernization. While the manufacturing technology began to explore product design and manufacturing processes, the nature of the information, on the other hand, to create technology to transform itself to adapt to the new information makes its manufacturing environment. Along with the manufacturing process and manufacturing systems to deepen understanding, researchers are trying to new concepts and approaches to their description and expression to achieve further control and optimization purposes.And manufacturing-related information mainly product information, technical information and information management in this area following major research direction and content :(1) manufacturing information acquisition, processing, storage, transmission and application of knowledge to create information and decision-making transformation.(2) Non-symbols expressing information, manufacturing information enables transmission, manufacturing information management, manufacturing informationintegrity in a state of non-production decision-making, management of virtual manufacturing, based on the network environment of the design and manufacturing, manufacturing process control and manufacturing systems science. These elements are manufactured in science and the scientific basis for the integration of product information, constitute the manufacture of the new branch of science -- to create informatics.2.2 Micro mechanical and manufacturing technology researchMicro-electronic mechanical systems (MEMS) refers to the collection of micro-sensors, micro-devices and the implementation of signal processing and control circuits, interface circuits, communications and power with the integration of micro-electromechanical system integrity. MEMS technology objectives through system miniaturization, to explore a new theory of integration, new functional components and systems. MEMS development will greatly facilitate the pocket of various products, miniaturization, a number of devices and systems to enhance the level of functional density, information density and Internet density, significantly saving, thin section. Not only can it reduce the cost of mechanical and electrical systems, but also to be completed and the size of many large systems impossible task. For example, using sophisticated 5μm diameter micro tweezers walls are made of a red blood cell can; Created to keep the cars 3mm size; In the magnetic field, like butterflies flying size aircraft. MEMS technology has opened up a completely new technology areas and industries, with many traditional sensors incomparable advantages in manufacturing, aerospace, transportation, telecommunications, agriculture, biomedical, environmental monitoring, military, families, and access to almost all areas have very broad application prospects.Micro machinery is machinery and electronic technology in nano-scale technology integration photogenic product. Back in 1959 scientists have raised the idea of micro-mechanical and micro-1962, the first silicon pressure sensors. 1987 California University of California Berkeley developed rotor diameter of the silicon micro-60~120 16ug m electrostatic electric motors, show produced using silicon micro-machining small movable structures and compatible with IC manufacturingmicro system potential. Micro-mechanical technology might like 20th century microelectronics technology, the technology of the world in the 21st century, economic development and national defense building a tremendous impact. Over the past 10 years, the development of micro-mechanical spectacular. Its characteristics are as follows : a considerable number of micro-components (micro structure, the implementation of micro-sensors and micro-machines, etc.) and micro-systems research success reflects the current and potential applications of value; The development of micro-manufacturing technology, particularly semiconductor processing technology have become small micro systems support technology; micro-electromechanical systems research needs of the interdisciplinary research team, micro-electromechanical systems technology in the development of microelectronics technology on the basis of multidisciplinary cross-frontier area of research, involving electronic engineering, mechanical engineering, materials engineering, physics, chemistry and biomedical engineering and other technical and scientific.The current micro-mechanical systems under the conditions of the campaign laws, the physical characteristics and micro components of the role of the mechanics payload acts lack adequate understanding is not yet in a theoretical basis for a micro-system design theory and methodology, and therefore can By experience and test methods research. Micro-mechanical systems, the existence of key scientific research issues of micro-scale system effects, physical properties and biochemical characteristics. Micro-system research are in the eve of a breakthrough, which is the in-depth study of the area.2.3 Material produced / manufactured parts integration of new technologies for processing.Material is a milestone in the progress of mankind, is the manufacturing and high-tech development. Every important to the success of the production and application of new materials, will promote the material and the promotion of national economic strength and military strength. 21, the world will be resource consumption-based economy to a knowledge-based industrial transformation for materials and parts and functions of a high performance, intelligent features; Requestmaterials and components designed to achieve quantitative-based and digitized; Prepare materials and components for the rapid, efficient and achieve both integration and integrated. Digital materials and components designed to be a simulation and optimization of materials and components to achieve high quality production / manufacturing and other integration, integrated manufacturing key. On the one hand, to be completed through computer simulation optimization can reduce the material is produced in the course of manufacture of spare parts and experimental links to the best craft programmes, materials and components to achieve high quality production / manufacturing; On the other hand, according to the requirements of different material properties, such as flexible modules volume, thermal expansion coefficient, magnetic performance, Research materials and components designed form. And the removal of traditional materials-manufacturing technology, and increase the level of information technology, the research group of synthetic materials is a process technology. Forming materials and components manufacture digital theory, technology and methods, such as rapid adoption of emerging technologies material growing principles, a breakthrough in the traditional law and to build law mechanical deformation processing many restrictions, no processing tools or dies, can rapidly create arbitrary complex shape and has a certain function 3D models or entity parts.2.4 machinery manufacturing breakthroughThe 21st century will be the century of life science, mechanical and life sciences depth integration will generate new concept products (such as better intelligence structure), to develop a new process (such as the growth processes shape) and the opening of new industries and to resolve product design, manufacturing processes and systems provide a series of problems new solutions. This is a highly innovative and leading edge area in the challenge.Earth's biological evolution in the long accumulated fine qualities of human manufacturing activities to address the various problems with examples and guidelines. Learning from life phenomena organizations operating complex systems and methods and techniques, manufacturing is the future solution to the current problems facing many an efficient way. Better manufacturing refers to the replicationof biological organs from organizations, since healing, self growth and evolution since the function of the model structure and operation of a manufacturing system and manufacturing process. If the manufacturing process mechanization, automation extends human physical and intelligent extension of the human intellectual, then "create better" may be said to extend its own organizational structure and human evolution process.Gene involved in the manufacture of biological science is the "self-organization" mechanism and its application in manufacturing systems. The so-called "self-organization" refers to a system in its internal mechanism driven by the organizational structure and operation mode learning, thereby enhancing the capacity for environmental adaptation process. Create better "since the organization" bottom-up mechanism for parallel product design and manufacturing processes of automatic generation, the dynamics of production systems and manufacturing systems and products more automatic a theoretical foundation and achieve superior conditions.Create a better manufacturing and life sciences "far edge hybrid" of the 21st century manufacturing will have an enormous impact. Create better research content is twofold :2.4.1 To create better livesResearch lives of the general phenomenon of the law and models, such as artificial life, cellular automatic machines, biological information processing skills, biological wisdom, biological-based organizational structure and mode of operation and the evolution of biological mechanisms and getting better;2.4.2 Oriented manufacturing breakthrough manufacturingResearch organizations better manufacturing systems since the mechanisms and methods, for example : based on full information-sharing breakthrough design principles, multi-discipline modules based on the distributed control and coordination mechanism based on the evolution of an excellent strategy; Study the concept of creating better system and its basis, such as : the formalization described space and better information shine upon relations better system and its evolution of complexity measurement methods.Machinery manufacturing is better and better mechanical science and life science, information science, materials science disciplines such as high integration, the study includes growth formative processes, better design and manufacturing systems, mechanical and biological wisdom better shape manufacturing. Currently doing research mostly forward exploratory work, with distinct characteristics of the basic research, if the research continues to seize opportunities that might arise revolutionary breakthroughs. Future research should concern areas of biological processing technology, better manufacturing system, based on rapid prototype manufacturing engineering technology organizations, as well as biological engineering related key technical basis.3. Modern manufacturing technology trendsSince the beginning of the 1990s, the nations of the world have manufacturing technology research and development as a national priority for the development of key technologies, such as the United States advanced manufacturing technology plan AMTP, Japan wisdom manufacturing technology (IMS) international cooperation schemes, Korea senior national plan of modern technology (G--7), Germany plans to manufacture 2000 and the EC Esprit and BRITE-EURAM plan.With the electronics, information, the constant development of new and high technologies, market demand individuality and diversity, the future of modern manufacturing technology to the overall development trends of the sophisticated, flexible, and networked, virtual and intelligent, green integrated, globalization direction.Current trends in modern manufacturing technology has the following nine areas :(1) Information technology, management techniques and technology closelyintegrated technology, modern production model will be continuousdevelopment.(2) Design techniques and more modern means.(3) Shaped and manufacture of sophisticated technology and manufacturingprocesses to achieve longer.(4) The formation of new special processing methods.(5) Development of a new generation of ultra-sophisticated, ultra-high-speedmanufacturing equipment.(6) Machining skills development for the engineering sciences.(7) Implementation of clean green manufacturing.(8)The widespread application of virtual reality technology to the manufacturingsector.(9) To create people-oriented.译文：先进制造技术的新发展摘要：本文介绍了当今制造技术面临的问题，论述了先进制造的前沿科学，并展望了先进制造技术的发展前景。
机械类英文文献+翻译
机器产业出书社2004年3月第1版20.9 MACHINABILITYThe machinability of a material usually defined in terms of four factors:1、Surface finish and integrity of the machined part;2、Tool life obtained;3、Force and power requirements;4、Chip control.Thus, good machinability good surface finish and integrity, long tool life, and low force And power requirements. As for chip control, long and thin (stringy) cured chips, if not broken up, can severely interfere with the cutting operation by becoming entangled in the cutting zone.Because of the complex nature of cutting operations, it is difficult to establish relationships that quantitatively define the machinability of a material. In manufacturing plants, tool life and surface roughness are generally considered to be the most important factors in machinability. Although not used much any more, approximate machinability ratings are available in the example below. Machinability Of SteelsBecause steels are among the most important engineering materials (as noted in Chapter 5), their machinability has been studied extensively. The machinability of steels has been mainly improved by adding lead and sulfur to obtain so-called free-machining steels.Resulfurized and Rephosphorized steels. Sulfur in steels forms manganese sulfide inclusions (second-phase particles), which act as stress raisers in the primary shear zone. As a result, the chips produced break up easily and are small; this improves machinability. The size, shape, distribution, and concentration of these inclusions significantly influence machinability. Elements such as tellurium and selenium, which are both chemically similar to sulfur, act as inclusion modifiers in resulfurized steels.Phosphorus in steels has two major effects. It strengthens the ferrite, causingincreased hardness. Harder steels result in better chip formation and surface finish. Note that soft steels can be difficult to machine, with built-up edge formation and poor surface finish. The second effect is that increased hardness causes the formation of short chips instead of continuous stringy ones, thereby improving machinability.Leaded Steels. A high percentage of lead in steels solidifies at the tip of manganese sulfide inclusions. In non-resulfurized grades of steel, lead takes the form of dispersed fine particles. Lead is insoluble in iron, copper, and alumin um and their alloys. Because of its low shear strength, therefore, lead acts as a solid lubricant (Section 32.11) and is smeared over the tool-chip interface du ring cutting. This behavior has been verified by the presence of high concentra tions of lead on the tool-side face of chips when machining leaded steels.When the temperature is sufficiently high-for instance, at high cutting spee ds and feeds (Section 20.6)—the lead melts directly in front of the tool, acting as a liquid lubricant. In addition to this effect, lead lowers the shear stress in the primary shear zone, reducing cutting forces and power consumption. Lead can be used in every grade of steel, such as 10xx, 11xx, 12xx, 41xx, etc. Le aded steels are identified by the letter L between the second and third numeral s (for example, 10L45). (Note that in stainless steels, similar use of the letter L means “low carbon,”a condition that improves their corrosion resistance.)However, because lead is a well-known toxin and a pollutant, there are se rious environmental concerns about its use in steels (estimated at 4500 tons of lead consumption every year in the production of steels). Consequently, there is a continuing trend toward eliminating the use of lead in steels (lead-free ste els). Bismuth and tin are now being investigated as possible substitutes for lea d in steels.Calcium-Deoxidized Steels. An important development is calcium-deoxidize d steels, in which oxide flakes of calcium silicates (CaSo) are formed. These f lakes, in turn, reduce the strength of the secondary shear zone, decreasing tool-chip interface and wear. Temperature is correspondingly reduced. Consequently, these steels produce less crater wear, especially at high cutting speeds.Stainless Steels. Austenitic (300 series) steels are generally difficult to mac hine. Chatter can be s problem, necessitating machine tools with high stiffness. However, ferritic stainless steels (also 300 series) have good machinability. Martensitic (400 series) steels are abrasive, tend to form a built-up edge, and req uire tool materials with high hot hardness and crater-wear resistance. Precipitati on-hardening stainless steels are strong and abrasive, requiring hard and abrasio n-resistant tool materials.The Effects of Other Elements in Steels on Machinability. The presence of aluminum and silicon in steels is always harmful because these elements com bine with oxygen to form aluminum oxide and silicates, which are hard and a brasive. These compounds increase tool wear and reduce machinability. It is es sential to produce and use clean steels.Carbon and manganese have various effects on the machinability of steels, depending on their composition. Plain low-carbon steels (less than 0.15% C) c an produce poor surface finish by forming a built-up edge. Cast steels are mor e abrasive, although their machinability is similar to that of wrought steels. To ol and die steels are very difficult to machine and usually require annealing pr ior to machining. Machinability of most steels is improved by cold working, w hich hardens the material and reduces the tendency for built-up edge formation.Other alloying elements, such as nickel, chromium, molybdenum, and vana dium, which improve the properties of steels, generally reduce machinability. T he effect of boron is negligible. Gaseous elements such as hydrogen and nitrog en can have particularly detrimental effects on the properties of steel. Oxygen has been shown to have a strong effect on the aspect ratio of the manganese sulfide inclusions; the higher the oxygen content, the lower the aspect ratio an d the higher the machinability.In selecting various elements to improve machinability, we should consider the possible detrimental effects of these elements on the properties and strengt h of the machined part in service. At elevated temperatures, for example, lead causes embrittlement of steels (liquid-metal embrittlement, hot shortness; see Se ction ), although at room temperature it has no effect on mechanical properties.Sulfur can severely reduce the hot workability of steels, because of the fo rmation of iron sulfide, unless sufficient manganese is present to prevent such formation. At room temperature, the mechanical properties of resulfurized steelsdepend on the orientation of the deformed manganese sulfide inclusions (aniso tropy). Rephosphorized steels are significantly less ductile, and are produced so lely to improve machinability.Machinability of Various Other MetalsAluminum is generally very easy to machine, although the softer grades te nd to form a built-up edge, resulting in poor surface finish. High cutting speed s, high rake angles, and high relief angles are recommended. Wrought aluminu m alloys with high silicon content and cast aluminum alloys may be abrasive; they require harder tool materials. Dimensional tolerance control may be a pro blem in machining aluminum, since it has a high thermal coefficient of expans ion and a relatively low elastic modulus.Beryllium is similar to cast irons. Because it is more abrasive and toxic, t hough, it requires machining in a controlled environment.Cast gray irons are generally machinable but are. Free carbides in castings reduce their machinability and cause tool chipping or fracture, necessitating to ols with high toughness. Nodular and malleable irons are machinable with hard tool materials.Cobalt-based alloys are abrasive and highly work-hardening. They require sharp, abrasion-resistant tool materials and low feeds and speeds.Wrought copper can be difficult to machine because of built-up edge form ation, although cast copper alloys are easy to machine. Brasses are easy to ma chine, especially with the addition pf lead (leaded free-machining brass). Bronz es are more difficult to machine than brass.Magnesium is very easy to machine, with good surface finish and prolong ed tool life. However care should be exercised because of its high rate of oxi dation and the danger of fire (the element is pyrophoric).Molybdenum is ductile and work-hardening, so it can produce poor surfac e finish. Sharp tools are necessary.Nickel-based alloys are work-hardening, abrasive, and strong at high tempe ratures. Their machinability is similar to that of stainless steels.Tantalum is very work-hardening, ductile, and soft. It produces a poor surf ace finish; tool wear is high.Titanium and its alloys have poor thermal conductivity (indeed, the lowest of all metals), causing significant temperature rise and built-up edge; they can be difficult to machine.Tungsten is brittle, strong, and very abrasive, so its machinability is low, although it greatly improves at elevated temperatures.Zirconium has good machinability. It requires a coolant-type cutting fluid, however, because of the explosion and fire.Machinability of Various MaterialsGraphite is abrasive; it requires hard, abrasion-resistant, sharp tools.Thermoplastics generally have low thermal conductivity, low elastic modul us, and low softening temperature. Consequently, machining them requires tools with positive rake angles (to reduce cutting forces), large relief angles, small depths of cut and feed, relatively high speeds, and proper support of the work piece. Tools should be sharp.External cooling of the cutting zone may be necessary to keep the chips f rom becoming “gummy”and sticking to the tools. Cooling can usually be achi eved with a jet of air, vapor mist, or water-soluble oils. Residual stresses may develop during machining. To relieve these stresses, machined parts can be an nealed for a period of time at temperatures ranging from to ( to ), and then cooled slowly and uniformly to room temperature.Thermosetting plastics are brittle and sensitive to thermal gradients during cutting. Their machinability is generally similar to that of thermoplastics.Because of the fibers present, reinforced plastics are very abrasive and are difficult to machine. Fiber tearing, pulling, and edge delamination are significa nt problems; they can lead to severe reduction in the load-carrying capacity of the component. Furthermore, machining of these materials requires careful rem oval of machining debris to avoid contact with and inhaling of the fibers.The machinability of ceramics has improved steadily with the development of nanoceramics (Section ) and with the selection of appropriate processing pa rameters, such as ductile-regime cutting (Section 22.4.2).Metal-matrix and ceramic-matrix composites can be difficult to machine, d epending on the properties of the individual components, i.e., reinforcing or wh iskers, as well as the matrix material.Thermally Assisted MachiningMetals and alloys that are difficult to machine at room temperature can be machined more easily at elevated temperatures. In thermally assisted machinin g (hot machining), the source of heat—a torch, induction coil, high-energy bea m (such as laser or electron beam), or plasma arc—is forces, (b) increased too l life, (c) use of inexpensive cutting-tool materials, (d) higher material-removal rates, and (e) reduced tendency for vibration and chatter.It may be difficult to heat and maintain a uniform temperature distribution within the workpiece. Also, the original microstructure of the workpiece may be adversely affected by elevated temperatures. Most applications of hot machi ning are in the turning of high-strength metals and alloys, although experiment s are in progress to machine ceramics such as silicon nitride.SUMMARYMachinability is usually defined in terms of surface finish, tool life, force and power requirements, and chip control. Machinability of materials depends n ot only on their intrinsic properties and microstructure, but also on proper sele ction and control of process variables.20.9 可机加工性一种质料的可机加工性通常以四种因素的方法界说：1、分的外貌光洁性和外貌完整性。
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。
（数控加工）机械类数控外文翻译外文文献英文文献数控
（数控加工）机械类数控外文翻译外文文献英文文献数控NumericalControlOneofthemostfundamentalconceptsintheareaofadvancedmanufacturingte chnologiesisnumericalcontrol(NC).PriortotheadventofNC,allmachinetools weremanualoperatedandcontrolled.Amongthemanylimitationsassociatedwith manualcontrolmachinetools,perhapsnoneismoreprominentthanthelimitation ofoperatorskills.Withmanualcontrol,thequalityoftheproductisdirectlyre latedtoandlimitedtotheskillsoftheoperator.Numericalcontrolrepresentst hefirstmajorstepawayfromhumancontrolofmachinetools.Numericalcontrolmeansthecontrolofmachinetoolsandothermanufacturin gsystemsthoughtheuseofprerecorded,writtensymbolicinstructions.Rathert hanoperatingamachinetool,anNCtechnicianwritesaprogramthatissuesoperat ionalinstructionstothemachinetool,Foramachinetooltobenumericallycontr olled,itmustbeinterfacedwithadeviceforacceptinganddecodingthep2ogramm edinstructions,knownasareader.Numericalcontrolwasdevelopedtoovercomethelimitationofhumanoperato r,andithasdoneso.Numericalcontrolmachinesaremoreaccuratethanmanuallyo peratedmachines,theycanproducepartsmoreuniformly,theyarefaster,andthe long-runtoolingcostsarelower.ThedevelopmentofNCledtothedevelopmentofs everalotherinnovationsinmanufacturingtechnology:1.Electricaldischargemachining.sercutting.3.Electronbeamwelding.Numericalcontrolhasalsomademachinetoolsmoreversatilethantheirmanuallyoperatedpredecessors.AnNCmachinetoolcanautomaticallyproduceawidev arietyofpar4s,eachinvolvinganassortmentofundertaketheproductionofprod uctsthatwouldnothavebeenfeasiblefromaneconomicperspectiveusingmanuall ycontrolledmachinetoolsandprocesses.Likesomanyadvancedtechnologies,NCwasborninthelaboratoriesoftheMas sachusettsInstituteofTechnology.TheconceptofNCwasdevelopedintheearly1 950swithfundingprovidedbytheU.SAirForce.Initsearlieststages,NCmachine swereabletomakestraightcutsefficientlyandeffectively.However,curvedpathswereaproblembecausethemachinetoolhadtobeprogra mmedtoundertakeaseriesofhorizontalandverticalstepstoproduceacurve.The shorteristhestraightlinesmakingupthestep,thesmootheris4hecurve.Eachli nesegmentinthestepshadtobecalculated.Thisproblemledtothedevelopmentin1959oftheAutomaticallyProgrammedT ools(APT)languageforNCthatusesstatementssimilartoEnglishlanguagetodef inethepartgeometry,describethecuttingtoolconfiguration,andspecifythen ecessarymotions.ThedevelopmentoftheAPTlanguagewasamajorstepforwardint hefurtherdevelopmentofNCtechnology.TheoriginalNCsystemwerevastlydiffe rentfromthoseusedpunchedpaper,whichwaslatertoreplacedbymagneticplasti ctape.Atapereaderwasusedtointerprettheinstructionswrittenonthetapefor themachine.Together,all/fthisrepresentedgiantstepforwardinthecontrolo fmachinetools.However,therewereanumberofproblemswithNCatthispointinit sdevelopment.Amajorproblemwasthefragilityofthepunchedpapertapemedium.Itwascomm onforthepapercontainingtheprogrammedinstructionstobreakortearduringam achiningprocess,Thisproblemwasexacerbatedbythefactthateachsuccessivet imeapartwasproducedonamachinetool,thepapertapecarryingtheprogrammedin structionshadtorerunthoughtthereader.Ifitwasnecessarytoproduce100copi esofagivenpart,itwasalsonecessarytorunthepapertapethoughtthereader100 separatetimes.Fragilepapertapessimplycouldnotwithstandtherigorsofshop floorenvironmentandthiskindofrepeateduse.Thisledtothedevelopmentofaspecialmagnetictape.Whereasthepapertape carriedtheprogrammedinstructionsasaseriesofholespunchedinthetape,theT hismostimportantofthesewasthatitwasdifficultorimpossibletochangethein structionsenteredonthetape.Tomakeeventhemostminoradjustmentsinaprogra mofinstructions,itwasnecessarytointerruptmachiningoperationsandmakean ewtape.Itwasalsostillnecessarytorunthetapethoughtthereaderasmanytimes astherewerepartstobeproduced.Fortunately,computertechnologybecomearea lityandsoonsolvedtheproblemsofNC,associatedwithpunchedpaperandplastic tape.Thedevelopmentofaconceptknownasnumericalcontrol(DNC)solvethepaper andplastictapeproblemsassociatedwithnumericalcontrolbysimplyeliminati ngtapeasthemediumforcarryingtheprogrammedinstructions.Indirectnumeric alcontrol,machinetoolsaretied,viaadatatransmissionlink,toahostcompute randfedtothemachinetoolasneededviathedatatransmissionlinkage.Directnumericalcontrolrepresentedamajorstepforwardoverpunchedtapeandplasticta pe.However,itissubjecttothesamelimitationasalltechnologiesthatdependo nahostcomputer.Whenthehostcomputergoesdown,themachinetoolsalsoexperie ncedowntime.Thisproblemledtothedevelopmentofcomputernumericalcontrol.Thedevelopmentofthemicroprocessorallowedforthedevelopmentofprogra mmablelogiccontrollers(PLC)andmicrocomputers.Thesetwotechnologiesallo wedforthedevelopmentofcomputernumericalcontrol(CNC).WithCNC,eachmachi netoolhasaPLCoramicrocomputerthatservesthesamepurpose.Thisallowsprogr Csolvedtheproblems associateddowntimeofthehostcomputer,butitintroducedanotherproblemknow nasdatamanagement.Thesameprogrammightbeloadedontendifferentmicrocompu terswithnocommunicationamongthem.Thisproblemisintheprocessofbeingsolv edbylocalareanetworksthatconnectDigitalSignalProcessorsTherearenumeroussituationswhereanalogsignalstobeprocessedinmanywa ys,likefilteringandspectralanalysis,Designinganaloghardwaretoperformt hesefunctionsispossiblebuthasbecomelessandpractical,duetoincreasedper formancerequirements,flexibilityneeds,andtheneedtocutdownondevelopmen t/testingtime.Itisinotherwordsdifficultpmdesignanaloghardwareanalysis ofsignals.Theactofsamplingansignalintothehatarespecialisedforembeddedsignal processingoperations,andsuchaprocessoriscalledaDSP,whichstandsforDigi talSignalProcessor.TodaytherearehundredsofDSPfamiliesfromasmanymanufacturers,eachonedesignedforaparticularprice/performance/usagegroup.Man yofthelargestmanufacturers,likeTexasInstrumentsandMotorola,offerboths pecialisedDSP’sforcertainfieldslikemotor-controlormodems,andgeneralh igh-performanceDSP’sthatcanperformbroadrangesofprocessingtasks.Devel opmentkitsan`softwarearealsoavailable,andtherearecompaniesmakingsoftw aredevelopmenttoolsforDSP’sthatallowstheprogrammertoimplementcomplex processingalgorithmsusingsimple“drag‘n’drop”methodologies.DSP’smoreorlessfallintotwocategoriesdependingontheunderlyingarch itecture-fixed-pointandfloating-point.Thefixed-pointdevicesgenerallyo perateon16-bitwords,whilethefloating-pointdevicesoperateon32-40bitsfl oating-pointwords.Needlesstosay,thefixed-pointdevicesaregenerallychea per.Anotherimportantarchitecturaldifferenceisthatfixed-pointprocessor stendtohaveanaccumulatorarchitecture,withonlyone“generalpurpose”reg ister,makingthemquitetrickytoprogramandmoreimportantly,makingC-compil ersinherentlyinefficient.Floating-pointDSP’sbehavemorelikecommongene ral-purposeCPU’s,withregister-files.TherearethousandsofdifferentDSP’sonthemarket,anditisdifficulttas kfindingthemostsuitableDSPforaproject.Thebestwayisprobablytosetupacon straintandwishlist,andtrytocomparetheprocessorsfromthebiggestmanufact urersagainstit.The“bigfour”manufacturersofDSPs:TexasInstruments,Motorola,AT&Ta ndAnalogDevices.Digital-to-analogconversionInthecaseofMPEG-Audiodecoding,digitalcompresseddataisfedintotheDS Pwhichperformsthedecoding,thenthedecodedsampleshavetobeconvertedbacki ntotheanalogdomain,andtheresultingsignalfedanamplifierorsimilaraudioe quipment.Thisdigitaltoanalogconversion(DCA)isperformedbyacircuitwitht hesamename&DifferentDCA’sprovidedifferentperformanceandquality,asmea suredbyTHD(Totalharmonicdistortion),numberofbits,linearity,speed,filt ercharacteristicsandotherthings.TheTMS320familyDQPofTexasInstrumentsTheTLS320familyconsistsoffixed-point,floating-point,multiprocesso rdigitalsignalprocessors(D[Ps),andfoxed-pointDSPcontrollers.TMS320DSP haveanarchitecturedesignedspecificallyforreal-timesignalprocessing.Th e’F/C240isanumberofthe’C2000DSPplatform,andisoptimizedforcontrolapp lications.The’C24xseriesofDSPcontrollerscombinesthisreal-timeprocess ingcapabilitywithcontrollerperipheralstocreateanidealsolutionforcontr olsystemapplications.ThefollowingcharacteristicsmaketheTMS320familyth erightchoiceforawiderangeofprocessingapplications:---Veryflexibleinstructionset---Inherentoperationalflexibility---High-speedperformance---Innovativeparallelarchitecture---CosteffectivenessDeviceswithinagenerationoftheTMS320familyhavethesameCPUstructure butdifferenton-chipmemoryandperipheralconfigurations.Spin-offdevicesu senewcombinationsofOn-chipmemoryandperipheralstosatisfyawiderangeofne edsintheworldwideelectronicsmarket.Byintegratingmemoryandperipheralso ntoasinglechip,TMS320devicesreducesystemcostsandsavecircuitboardspace .The16-bit,fixed-pointDSPcoreofthe‘C24xdevicesprovidesanalogdesi gnersadigitalsolutionthatdoesnotsacrificetheprecisionandperformanceof theirsystemperformancecanbeenhancedthroughtheuseofadvancedcontrolalgo rithmsfortechniquessuchasadaptivecontrol,Kalmanfiltering,andstatecont rol.The‘C24xDSPcontrollerofferreliabilityandprogrammability.Analogco ntrolsystems,ontheotherhand,arehardwiredsolutionsandcanexperienceperf ormancedegradationduetoaging,componenttolerance,anddrift.Thehigh-speedcentralprocessingunit(CPU)allowsthedigitaldesignert oprocessalgorithmsinrealtimeratherthanapproximateresultswithlook-upta bles.TheinstructionsetoftheseDSPcontrollers,whichincorporatesbothsign alprocessinginstructionsandgeneral-purposecontrolfunctions,coupledwit htheextensivedevelopmenttimeandprovidesthesameeaseofuseastraditional8 -and16-bitmicrocontrollers.Theinstructionsetalsoallowsyoutoretainyour softwareinvestmentwhenmovingfromothergeneral-purpose‘C2xxgeneration, sourcecodecompatiblewiththe’C2xgeneration,andupwardlysourcecodecompa tiblewiththe‘C5xgenerationofDSPsfromTexasInstruments.The‘C24xarchitectureisalsowell-suitedforprocessingcontrolsignal s.Itusesa16-bitwordlengthalongwith32-bitregistersforstoringintermedia teresults,andhastwohardwareshiftersavailabletoscalenumbersindependent lyoftheCPU.Thiscombinationminimizesquantizationandtruncationerrors,an dincreasesp2ocessingpowerforadditionalfunctions.Suchfunctionsmightinc ludeanotchfilterthatcouldcancelmechanicalresonancesinasystemoranestim ationtechniquethatcouldeliminatestatesensorsinasystem.The‘C24xDSPcontrollerstakeadvantageofansetofperipheralfunctions thatallowTexasInstrumentstoquicklyconfigurevariousseriesmembersfordif ferentprice/performancepointsorforapplicationoptimization.Thislibraryofbothdigitalandmixed-signalperipheralsincludes:---Timers---Serialcommunicationsports(SCI,SPI)---Analog-to-digitalconverters(ADC)---Eventmanager---Systemprotection,suchaslow-voltageandwatchdogtimerTheDSPcontrollerperipherallibraryiscontinuallygrowingandchanging tosuittheoftomorrow’sembeddedcontrolmarketplace.TheTMS320F/C240isthefirststandarddeviceintroducedinthe‘24xserie sofDSPcontrollers.Itsetsthestandardforasingle-chipdigitalmotorcontrol ler.The‘240canexecute20MIPS.Almostallinstructionsareexecutedinasimpl ecycleof50ns.Thishighperformanceallowsreal-timeexecutionofverycomple8controlalgorithms,suchasadaptivecontrolandKalmanfilters.Veryhighsampl ingratescanalsobeusedtominimizeloopdelays.The‘240hasthearchitecturalfeaturesnecessaryforhigh-speedsignalp rocessinganddigitalcontrolfunctions,andithastheperipheralsneededtopro videasingle-chipsolutionformotorcontrolapplications.The‘240ismanufac turedusingsubmicronCMOStechnology,achievingalogpowerdissipationrating.A lsoincludedareseveralpower-downmodesforfurtherpowersavings.Someapplic ationsthatbenefitfromtheadvancedprocessingpowerofthe‘240include: ---Industrialmotordrives---Powerinvertersandcontrollers---Automotivesystems,suchaselectronicpowersteering,antilockbrake s,andclimatecontrol---ApplianceandHVACblower/compressormotorcontrols---Printers,copiers,andotherofficeproducts---Tapedrives,magneticopticaldrives,andothermassstorageproducts---RoboticandCNCmillingmachinesTofunctionasasystemmanager,aDSPmusthaverobuston-chipI/Oandotherp eripherals.Theeventmanagerofthe‘240isunlikeanyotheravailableonaDSP.T hisapplication-optimizedperipheralunit,coupledwiththehighperformanceD SPcore,enablestheuseofadvancedcontroltechniquesforhigh-precisionandhi gh-efficiencyfullvariable-speedcontrolofallmotortypes.Includeintheeve ntmanagerarespecialpulse-widthmodulation(PWM)generationfunctions,suchasaprogrammabledead-bandfunctionandaspacevectorPWMstatemachinefor3-ph asemotorsthatprovidesstate-of-the-artmaximumefficiencyintheswitchingo fpowertransistors.Thereindependentupdowntimers,eachwithit’sowncompareregister,sup portthegenerationofasymmetric(noncentered)aswellassymmetric(centered) PWMwaveforms.Open-LoopandClosed-LoopControlOpen-loopControlSystemsThewordautomaticimpliesthatthereisacertainamountofsophistication inthecontrolsystem.Byautomatic,itgenerallymeansThatthesystemisusually capableofadaptingtoavarietyofoperatingconditionsandisabletorespondtoa classofinputssatisfactorily.However,notanytypeofcontrolsystemhastheau ually,theautomaticfeatureisachievedbyfeed.gthefeedbackstructure,itiscalledanopen-loopsystem,whichisthesimp lestandmosteconomicaltypeofcontrolsystem.inaccuracyliesinthefactthato nemaynotknowtheexactcharacteristicsofthefurther,whichhasadefinitebear ingontheindoortemperature.Thisalcopointstoanimportantdisadvantageofth eperformanceofanopen-loopcontrolsystem,inthatthesystemisnotcapableofa daptingtovariationsinenvironmentalconitionsortoexternaldisturbances.I nthecaseofthefurnacecontrol,perhapsanexperiencedpersoncanprovidecontr olforacertaindesiredtemperatureinthehouse;butidthedoorsorwindowsareop enedorclosedintermittentlyduringtheoperatingperiod,thefinaltemperatureinsidethehousewillnotbeaccuratelyregulatedbytheopen-loopcontrol.Anelectricwashingmachineisanothertypicalexampleofanopen-loopsyst em,becausetheamountofwashtimeisentirelydeterminedbythejudgmentandesti mationofthehumanoperator.Atrueautomaticelectricwashingmachineshouldha vethemeansofcheckingthecleanlinessoftheclothescontinuouslyandturnitse dtoffwhenthedesireddegisedofcleanlinessisreached.Closed-LoopControlSystemsWhatismissingintheopen-loopcontrolsystemformoreaccurateandmoread aptablecontrolisalinkorfeedbackfromtheoutputtotheinputofthesystem.Ino rdertoobtainmoreaccuratebontrol,thecontrolledsignalc(t)mustbefedbacka ndcomparedwiththereferenceinput,andanactuatingsignalproportionaltothe differenceoftheoutputandtheinputmustbesentthroughthesystemtocorrectth eerror.Asystemwithoneormorefeedbackpat(slikethatjustdescribediscalled aclosed-loopsystem.humanbeingareprobablythemostcomplexandsophisticate dfeedbackcontrolsysteminexistence.Ahumanbeingmaybeconsideredtobeacont rolsystemwithmanyinputsandoutputs,capableofcarryingouthighlycomplexop erations.Toillustratethehumanbeingasafeedbackcontrolsystem,letusconsidert hattheobjectiveistoreachforanobjectonaperformthetask.Theeyesserveasas ensingdevicewhichfeedsbackcontinuouslythepositionofthehand.Thedistanc ebetweenthehandandtheobjectistheerror,whichiseventuallybroughttozeroa sthehandreachertheobject.Thisisatypicalexampleofclosed-loopcontrol.However,ifoneistoldtoreachfortheobjectandthenisblindolded,onecanonlyrea chtowardtheobjectbyestimatingitsexactposition.ItisAsantherillustrativ eexampleofaclosed-loopcontrolsystem,showstheblockdiagramoftherudderco ntrolsystemofThebasicalementsandtheblocadiagramofaclosed-loopcontrols ystemareshowninfig.Ingeneral,theconfigurationofafeedbackcontrolsystem maynotbeconstrainedtothatoffig&.Incomplexsystemstheremaybemultitudeof feedbackloopsandelementblocks.数控在先进制造技术领域最根本的观念之壹是数控（NC）。
先进制造技术(有出处)--中英文翻译
毕业设计（论文）外文资料翻译系别：机械工程学院专业：机械设计制造及其自动化外文出处：Advanced Manufacturing Technology附件：1、外文原文；2、外文资料翻译译文。
1、外文原文（复印件）2、外文资料翻译译文先进制造技术尽管裁断的深度是由材料去除率的总额决定的，增加径向的裁断深度同样能够增加磨损率。
就像增加进给速度一样，工具的使用寿命会随着切削深度的加深而缩短。
因此，工具的使用寿命与磨损率能够像预期那样保持平衡。
每个金属在切削过程中会产生三个力：切向力，即零件运转时产生的力;径向力，由工件材料切削深度的阻隔产生的力；纵向力，利用进给速度产生的力。
这些力比机器运转过程中产生的力强30%到80%。
例如，在洛氏硬度62HRC的强度下，分别经过预热处理和热处理，纵向力会从30%增加到50%，切向力会从30%增加到50%，径向力会从70%增加到100%。
因此，机床必须能够承受不断增加的切削力，尤其是径向的切削力。
切削液能够影响白层的产生，因为白层是物象变化在表面发生的结果，当冷却工件表面时，切削液能够减轻热损坏。
一些报道认为切削液会消除白层，但却有研究表明切削液没有这样的作用。
刀具状态也是一个很重要的因素，然而白层的增加同样伴随着刀具的磨损。
如果硬态切削能够代替精磨操作，硬态切削的产品表面光洁度能够与精磨操作相媲美。
与精磨操作不同的是，表面光洁度是由大小，形状，强度和在磨削砂轮中磨粒的作用决定的。
硬车削表面通常是由切削过程中形成的几何图形决定的，其中主要是由切削工具的进给和刀尖半径决定的。
对于磨削圆柱的应用，其砂轮和工件必须能够顺利的旋转。
其次，砂轮飞快旋转的同时工件要缓慢的旋转。
如果旋转的构件不完全同心，组合的缺陷和旋转速度的细微差别会引起圆柱的凸角。
当生产的几何图形不够圆时，这会影响最终的生产。
另一方面，对于硬切削来说，工件或者切削工具不能同时旋转。
因此，机器加工表面将会与机床主轴和紧挨机床的中心线的机床纵向的方向一样精准。
机械类英语论文及翻译翻译
High-speed millingHigh-speed machining is an advanced manufacturing technology, different from the traditional processing methods. The spindle speed, cutting feed rate, cutting a small amount of units within the time of removal of material has increased three to six times. With high efficiency, high precision and high quality surface as the basic characteristics of the automobile industry, aerospace, mold manufacturing and instrumentation industry, such as access to a wide range of applications, has made significant economic benefits, is the contemporary importance of advanced manufacturing technology. For a long time, people die on the processing has been using a grinding or milling EDM (EDM) processing, grinding, polishing methods. Although the high hardness of the EDM machine parts, but the lower the productivity of its application is limited. With the development of high-speed processing technology, used to replace high-speed cutting, grinding and polishing process to die processing has become possible. To shorten the processing cycle, processing and reliable quality assurance, lower processing costs.1 One of the advantages of high-speed machiningHigh-speed machining as a die-efficient manufacturing, high-quality, low power consumption in an advanced manufacturing technology. In conventional machining in a series of problems has plagued by high-speed machining of the application have been resolved.1.1 Increase productivityHigh-speed cutting of the spindle speed, feed rate compared withtraditional machining, in the nature of the leap, the metal removal rate increased 30 percent to 40 percent, cutting force reduced by 30 percent, the cutting tool life increased by 70% . Hardened parts can be processed, a fixture in many parts to be completed rough, semi-finishing and fine, and all other processes, the complex can reach parts of the surface quality requirements, thus increasing the processing productivity and competitiveness of products in the market.1.2 Improve processing accuracy and surface qualityHigh-speed machines generally have high rigidity and precision, and other characteristics, processing, cutting the depth of small, fast and feed, cutting force low, the workpiece to reduce heat distortion, and high precision machining, surface roughness small. Milling will be no high-speed processing and milling marks the surface so that the parts greatly enhance the quality of the surface. Processing Aluminum when up Ra0.40.6um, pieces of steel processing at up to Ra0.2 ~ 0.4um.1.3 Cutting reduce the heatBecause the main axis milling machine high-speed rotation, cutting a shallow cutting, and feed very quickly, and the blade length of the workpiece contacts and contact time is very short, a decrease of blades and parts of the heat conduction. High-speed cutting by dry milling or oil cooked up absolute (mist) lubrication system, to avoid the traditional processing tool in contact with the workpiece and a lot of shortcomings to ensure that the tool is not high temperature under the conditions of work, extended tool life.1.4 This is conducive to processing thin-walled partsHigh-speed cutting of small cutting force, a higher degree of stability, Machinable with high-quality employeescompared to the company may be very good, but other than the company's employees may Suanbu Le outstanding work performance. For our China practice, we use the models to determine the method of staff training needs are simple and effective. This study models can be an external object, it can also be a combination of internal and external. We must first clear strategy for the development of enterprises. Through the internal and external business environment and organizational resources, such as analysis, the future development of a clear business goals and operational priorities. According to the business development strategy can be compared to find the business models, through a comparative analysis of the finalization of business models. In determining business models, a, is the understanding of its development strategy, or its market share and market growth rate, or the staff of the situation, and so on, according to the companies to determine the actual situation. As enterprises in different period of development, its focus is different, which means that enterprises need to invest the manpower and financial resources the focus is different. So in a certain period of time, enterprises should accurately selected their business models compared with the departments and posts, so more practical significance, because the business models are not always good, but to compare some aspects did not have much practical significance, Furthermore This can more fully concentrate on the business use of limited resources. Identify business models, and then take the enterprise of the corresponding departments and staff with the business models for comparison, the two can be found in the performance gap, a comparative analysis to find reasons, in accordance with this business reality, the final identification of training needs. The cost of training is needed, if not through an effective way to determine whether companies need to train and the training of the way, but blind to training, such training is difficult to achieve the desired results. A comparison only difference between this model is simple and practical training.1.5 Can be part of some alternative technology, such as EDM, grinding high intensity and high hardness processingHigh-speed cutting a major feature of high-speed cutting machine has the hardness of HRC60 parts. With the use of coated carbide cutter mold processing, directly to the installation of a hardened tool steel processing forming, effectively avoid the installation of several parts of the fixture error and improve the parts of the geometric location accuracy. In the mold of traditional processing, heat treatment hardening of the workpiece required EDM, high-speed machining replace the traditional method of cutting the processing, manufacturing process possible to omit die in EDM, simplifying the processing technology and investment costs .High-speed milling in the precincts of CNC machine tools, or for processing centre, also in the installation of high-speed spindle on the general machine tools. The latter not only has the processing capacity of general machine tools, but also for high-speed milling, a decrease of investment in equipment, machine tools increased flexibility. Cutting high-speed processing can improve the efficiency, quality improvement, streamline processes, investment and machine tool investment and maintenance costs rise, but comprehensive, can significantly increase economic efficiency.2 High-speed millingHigh-speed milling the main technical high-speed cutting technology is cutting the development direction of one of it with CNC technology, microelectronic technology, new materials and new technology, such as technology development to a higher level. High-speed machine tools and high-speed tool to achieve high-speed cutting is the prerequisite and basic conditions, in high-speed machining in the performance of high-speed machine tool material of choice and there are strict requirements.2.1 High-speed milling machine in order to achieve high-speed machiningGeneral use of highly flexible high-speed CNC machine tools, machining centers, and some use a dedicated high-speed milling, drilling. At the same time a high-speed machine tool spindle system and high-speed feeding system, high stiffness of the main characteristics of high-precision targeting and high-precision interpolation functions, especially high-precision arc interpolation function. High-speed machining systems of the machine a higher demand, mainly in the following areas:General use of highly flexible high-speed CNC machine tools, machining centers, and some use a dedicated high-speed milling, drilling. At the same time a high-speed machine tool spindle system and high-speed feeding system, high stiffness of the main characteristics of high-precision targeting and high-precision interpolation functions, especially high-precision arc interpolation function. High-speed machining systems of the machine a higher demand, mainly in the following areas:High-speed milling machine must have a high-speed spindle, the spindle speed is generally 10000 ~ 100000 m / min, power greater than 15 kW. But also with rapid speed or in designated spots fast-stopping performance. The main axial space not more than 0 .0 0 0 2 m m. Often using high-speed spindle-hydrostatic bearings, air pressure-bearing, mixed ceramic bearings, magnetic bearing structure of the form. Spindle cooling general use within the water or air cooled.High-speed processing machine-driven system should be able to provide 40 ~ 60 m / min of the feed rate, with good acceleration characteristics, can provide 0.4 m/s2 to 10 m/s2 acceleration and deceleration. In order to obtain good processing quality, high-speed cutting machines must have a high enough stiffness. Machine bed material used gray iron, can also add a high-damping base of concrete, to prevent cutting tool chatter affect the quality of processing. A high-speed data transfer rate, can automatically increase slowdown. Processing technology to improve the processing and cutting tool life. At present high-speed machine tool manufacturers, usually in the general machine tools on low speed, the feed of the rough and then proceed to heat treatment, the last in the high-speed machine on the half-finished and finished, in improving the accuracy and efficiency at the same time, as far as possible to reduce processing Cost.2.2 High-speed machining toolHigh-speed machining tool is the most active one of the important factors, it has a direct impact on the efficiency of processing, manufacturing costs and product processing and accuracy. Tool in high-speed processing to bear high temperature, high pressure, friction, shock and vibration, such as loading, its hardness and wear-resistance, strength and toughness, heat resistance, technology and economic performance of the basic high-speed processing performance is the key One of the factors. High-speed cutting tool technology development speed, the more applications such as diamond (PCD), cubic boron nitride (CBN), ceramic knives, carbide coating, (C) titanium nitride Carbide TIC (N) And so on. CBN has high hardness, abrasion resistance and the extremely good thermal conductivity, and iron group elements between the great inertia, in 1300 ℃ would not have happened significant role in the chemical, also has a good stability. The experiments show that with CBN cutting toolHRC35 ~ 67 hardness of hardened steel can achieve very high speed. Ceramics have good wear resistance and thermal chemical stability, its hardness, toughness below the CBN, can be used for processing hardness of HRC <5 0 parts. Carbide Tool good wear resistance, but the hardness than the low-CBN and ceramics. Coating technologyused knives, cutting tools can improve hardness and cutting the rate, for cutting HRC40 ~ 50 in hardness between the workpiece. Can be used to heat-resistant alloys, titanium alloys, hightemperature alloy, cast iron, Chungang, aluminum and composite materials of high-speed cutting Cut, the most widely used. Precision machining non-ferrous metals or non-metallic materials, or the choice of polycrystalline diamond Gang-coated tool.2.3 High-speed processing technologyHigh-speed cutting technology for high-speed machining is the key. Cutting Methods misconduct, will increase wear tool to less than high-speed processing purposes. Only high-speed machine tool and not a good guide technology, high-speed machining equipment can not fully play its role. In high-speed machining, should be chosen with milling, when the milling cutter involvement with the workpiece chip thickness as the greatest, and then gradually decreased. High-speed machining suitable for shallow depth of cut, cutting depth of not more than 0.2 mm, to avoid the location of deviation tool to ensure that the geometric precision machining parts. Ensure that the workpiece on the cutting constant load, to get good processing quality. Cutting a single high-speed milling path-cutting mode, try not to interrupt the process and cutting tool path, reducing the involvement tool to cut the number to be relatively stable cutting process. Tool to reduce the rapid change to, in other words when the NC machine tools must cease immediately, or Jiangsu, and then implement the next step. As the machine tool acceleration restrictions, easy to cause a waste of time, and exigency stop or radical move would damage the surface accuracy. In the mold of high-speed finishing, in each Cut, cut to the workpiece, the feed should try to change the direction of a curve or arc adapter, avoid a straight line adapter to maintain the smooth process of cutting.3 Die in high-speed milling processing ofMilling as a highly efficient high-speed cutting of the new method,inMould Manufacturing has been widely used. Forging links in the regular production model, with EDM cavity to be 12 ~ 15 h, electrodes produced 2 h. Milling after the switch to high-speed, high-speed milling cutter on the hardness of HRC 6 0 hardened tool steel processing. The forging die processing only 3 h20min, improve work efficiency four to five times the processing surface roughness of Ra0.5 ~ 0.6m, fully in line with quality requirements.High-speed cutting technology is cutting technology one of the major developments, mainly used in automobile industry and die industry, particularly in the processing complex surface, the workpiece itself or knives rigid requirements of the higher processing areas, is a range of advanced processing technology The integration, high efficiency and high quality for the people respected. It not only involves high-speed processing technology, but also including high-speed processing machine tools, numerical control system, high-speed cutting tools and CAD / CAM technology. Die-processing technology has been developed in the mold of the manufacturing sector in general, and in my application and the application of the standards have yet to be improved, because of its traditional processing with unparalleled advantages, the future will continue to be an inevitable development of processing technology Direction.4 Numerical control technology and equipping development trend and countermeasureEquip 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 hisindustry, aviation, spaceflight, etc. national defense industry) last technology and getting more basic most equipment. Marx has ever said "the differences of different economic times, do not lie in what is produced, and lie in how to produce, produce with some means of labor ". Manufacturing technology and equipping the most basic means of production that are that the mankind produced the activity, and numerical control technology is nowadays advanced manufacturing technology and equips the most central technology. Nowadays the manufacturing industry all around the world adopts numerical control technology extensively, in order to improve manufacturing capacity and level, improve the adaptive capacity and competitive power to the changeable market of the trends. In addition every industrially developed country in the world also classifies the technology and numerical control equipment of numerical control as the strategic materials of the country, not merely take the great measure to develop one's own numerical control technology and industry, and implement blockading and restrictive policy to our country in view of " high-grade, precision and advanced key technology of numerical control " and equipping. In a word, develop the advanced manufacturing technology taking numerical control technology as the core and already become every world developed country and accelerate economic development in a more cost-effective manner, important way to improve the overall national strength and national position.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, namely the so-called digitization is equipped, its technological range covers a lot of fields: (1)Mechanical manufacturing technology; (2)Information processing, processing, transmission technology; (3)Automatic control technology; (4)Servo drive technology; (5)Technology of the sensor; (6)Software engineering ,etc..Development trend of a numerical control technologyThe application of numerical control technology has not only brought the revolutionary change to manufacturing industry of the tradition, make the manufacturing industry become the industrialized symbol , and with the constant development of numerical control technology and enlargement of the application, the development of some important trades (IT , automobile , light industry , medical treatment ,etc. ) to the national economy and the people's livelihood of his plays a more and more important role, because the digitization that these trades needed to equip has already been the main trend of modern development. Numerical control technology in the world at present and equipping the development trend to see, there is the following several respect [1- ] in its main research focus.5 A high-speed, high finish machining technology and new trend equippedThe efficiency, quality are subjavanufacturing technology. High-speed, high finish machining technology can raise the efficiency greatly , improve the quality and grade of the products, shorten production cycle and improve the market competitive power. Japan carries the technological research association first to classify it as one of the 5 great modern manufacturing technologies for this, learn (CIRP) to confirm it as the centre in the 21st century and study one of the directions in international production engineering.In the field of car industry, produce one second when beat such as production of 300,000 / vehicle per year, and many variety process it is car that equip key problem that must be solved one of; In the fields of aviation and aerospace industry, spare parts of its processing are mostly the thin wall and thin muscle, rigidity is very bad, the material is aluminium or aluminium alloy, only in a situation that cut the speed and cut strength very small high,could process these muscles, walls. Adopt large-scale whole aluminium alloy method that blank " pay empty " make the wing recently, such large-scale parts as the fuselage ,etc. come to substitute a lot of parts to assemble through numerous rivet , screw and other connection way, make the intensity , rigidity and dependability of the component improved. All these, to processing and equipping the demand which has proposed high-speed, high precise and high flexibility.According to EMO2001 exhibition situation, high-speed machining center is it give speed can reach 80m/min is even high , air transport competent speed can up to 100m60m/min of speed, it is 100m/min to be fast, the acceleration reaches 2g, the rotational speed of the main shaft has already reached 60 000r/min. Processing a thin wall of plane parts, spend 30min only, and same part general at a high speed milling machine process and take 3h, the ordinary milling machine is being processed to need 8h; The speed and acceleration of main shaft of dual main shaft lathes of Germany DMG Company are up to 120000r/mm and 1g.In machining accuracy, the past 10 years, ordinary progression accuse of machining accuracy o f lathe bring 5μm up to from 10μm already, accurate grades of machining center from 3～5μm, rise to 1～1.5μm, and ultraprecision machining accuracy is it enter nanometer grade to begin already (0.01μm).In dependability, MTBF value of the foreign numerical control device has already reached above 6 000h, MTBF value of the servo system reaches above 30000h, demonstrate very high dependability .In order to realize high-speed, high finish machining, if the part of function related to it is electric main shaft, straight line electrical machinery get fast development, the application is expanded further .5.2 Link and process and compound to process the fast development of the lathe in 5 axesAdopt 5 axles to link the processing of the three-dimensional curved surface part, can cut with the best geometry form of the cutter , not only highly polished, but also efficiency improves by a large margin . It is generally acknowledged, the efficiency of an 5 axle gear beds can equal 2 3 axle gear beds, is it wait for to use the cubic nitrogen boron the milling cutter of ultra hard material is milled and pared at a high speed while quenching the hard steel part, 5 axles link and process 3 constant axles to link and process and give play to higher benefit. Because such reasons as complicated that 5 axles link the numerical control system , host computer structure that but go over, it is several times higher that its price links the numerical control lathe than 3 axles , in addition the technological degree of difficulty of programming is relatively great, have restricted the development of 5 axle gear beds.At present because of electric appearance of main shaft, is it realize 5 axle complex main shaft hair structure processed to link greatly simplify to make, it makes degree of difficulty and reducing by a large margin of the cost, the price disparity of the numerical control system shrinks. So promoted 5 axle gear beds of head of complex main shaft and compound to process the development of the lathe (process the lathe including 5).At EMO2001 exhibition, new Japanese 5 of worker machine process lathe adopt complex main shaft hair, can realize the processing of 4 vertical planes and processing of the wanton angle, make 5 times process and 5 axles are processed and can be realized on the same lathe, can also realize the inclined plane and pour the processing of the hole of awls. Germany DMG Company exhibits the DMUVoution series machining center, but put and insert and put processing and 5 axles 5 times to link and process in once, can be controlled by CNC system or CAD/CAM is controlled directly or indirectly.5Japan, ONC (Open Numerical Control System) of China, etc.. The numerical control system melts to become the future way of the numerical control system open. The so-called open numerical control system is the development ofthe numerical control system can be on unified operation platform, face the lathe producer and end user, through changing, increasing or cutting out the structure target(numerical control function), form the serration, and can use users specially conveniently and the technical know-how is integrated in the control system, realize the open numerical control system of different variety , different grade fast, form leading brand products with distinct distinction. System structure norm of the open numerical control system at present, communication norm , disposing norm , operation platform , numerical control systematic function storehouse and numerical control systematic function software development ,etc. are the core of present research.The networked numerical control equipment is a new light spot of the fair of the internationally famous lathe in the past two years. Meeting production line , manufacture system , demand for the information integration of manufacturing company networkedly greatly of numerical control equipment, realize new manufacture mode such as quick make , fictitious enterprise , basic Entrance that the whole world make too. Some domestic and international famous numerical control lathes and systematic manufacturing companies of numerical control have all introduced relevant new concepts and protons of a machine in the past two years, if in EMO2001 exhibition, " Cyber Production Center " that the company exhibits of mountain rugged campstool gram in Japan (Mazak) (intellectual central production control unit, abbreviated as CPC); The lathe company of Japanese big Wei (Okuma ) exhibits " IT plaza " (the information technology square , is abbreviated as IT square ); Open Manufacturing Environment that the company exhibits of German Siemens (Siemens ) (open the manufacturing environment, abbreviated as OME),etc., have reflected numerical control machine tooling to the development trend of networked direction.5.4 Pay attention to the new technical standard, normal setting-up5.4.1 system of China too in 2000.5.4.2 About the numerical control standardThe numerical control standard is a kind of trend of information-based development of manufacturing industry. Information exchange among 50 years after numerical control technology was born was all because of ISO6983 standard, namely adopt G, M code describes how processes, its essential characteristic faces the processing course, obviously, he can't meet high-speed development of modern numerical control technology's needs more and more already. For this reason, studying and making a kind of new CNC system standard ISO14649 (STEP-NC) in the world, its purpose is to offer a kind of neutral mechanism not depending on the concrete system, can describe the unified data model in cycle of whole life of the products, thus realize the whole manufacture process, standardization of and even each industrial field product information.The appearance of STEP-NC may be a revolution of the technological field of the numerical control, on the development and even the whole manufacturing industry of numerical control technology, will exert a far-reaching influence. First of all, STEP-NC puts forward a kind of brand-new manufacture idea, in the traditional manufacture idea, NC processes the procedures to all concentrate on individual computer. Under the new standard, NC procedure can be dispersed on Internet, this is exactly a direction of open , networked development of numerical control technology. Secondly, STEP-NC numerical control system can also reduce and process the drawing (about 75%), process the procedure to work out the time (about 35%) and process the time (about 50%) greatly.At present, American-European countries pay much attention to the research of STEP-NC, EuropeJapannumerical control at present.6 pairs of basic estimations of technology and industry development of numerical control of our countryThe technology of numerical control of our country started in 1958, the development course in the past 50 years can roughly be divided into 3 stages: The first stage is from 1958 to 1979, namely closed developing stage. In this stages, because technology of foreign countries blockade and basic restriction of terms of our country, the development of numerical control technology is comparatively slow. During "Sixth Five-Year Plan Period" , " the Seventh Five-Year Plan Period " of the country in second stage and earlier stage in " the Eighth Five-Year Plan Period ", namely introduce technology, digest and assimilate, the stage of establishing the system of production domesticization arisesing tentatively. At this stage , because of reform and opening-up and national attention , and study the improvement of the development environment and international environment, research , development and all making considerable progress in production domesticization of the products of the technology of numerical control of our country. The third stage is and during the "Ninth Five-Year Plan Period" on the later stage in "the Eighth Five-Year Plan Period" of the country, namely implement the research of industrialization, enter market competition stage. At this stage, made substantive progress in industrialization of the domestic numerical control equipment of our country. In latter stage for "the Ninth Five-Year Plan ", the domestic occupation rate of market of the domestic numerical control lathe is up to 50%, it is up to 10% too to mix the domestic numerical control system (popular).Make a general survey of the development course in the past 50 years of technology of numerical control of our country, especially through tackling key problems of 4 Five-Year Plans, all in all has made following achievements.a. Have established the foundation of the technical development of numerical control, has mastered modern numerical control technology basically. Our country has already, the numerical control host computer, basic technology of special plane and fittings grasped and driven from the numerical control system and survey basically now, among them most technology have already possessed and commercialized the foundation developed, some technology has already, industrialization commercialized.b. Have formed the industrial base of numerical control tentatively. In tackling key problems the foundation that the achievement and some technology commercialize, set up the systematic factories of numerical control with production capacity in batches such as numerical control in Central China, numerical control of the spaceflight etc.. Electrical machinery plant of Lanzhou, such factory and the first machine tool plant of Beijing , the first machine tool plant of Jinan ,etc. several numerical control host computer factories of a batch of servo systems and servo electrical machineries as the numerical control in Central China, etc.. These factories have formed the numerical control industrial base of our country basically.c. Have set up a numerical control research, development, managerial talent's basic team.Though has made considerable progress in research and development and industrialization of numerical control technology, but we will realize soberly, the research and development of the technology of advanced numerical control of our country, especially there is greater disparity in current situation and current demand of our country of engineering level in industrialization. Though very fast from watching the development of our country vertically, have disparity horizontally more than (compare foreign countries with) not merely engineering level, there is disparity too in development speed in some aspects, namely the engineering level disparity between some high-grade , precision and advanced numerical control equipment has the tendency to expand . Watch from world, estimate roughly as follows about the engineering level of numerical control of our country and industrialization level.a. On the engineering level, in probably backward 10-1 years with the advanced level in foreign countries, it is。
先进制造的英文作文带翻译
先进制造的英文作文带翻译Advanced Manufacturing。
Advanced manufacturing refers to the use of cutting-edge technology, innovative processes, and sophisticated materials to produce goods more efficiently and effectively than traditional manufacturing methods. This approach encompasses a wide range of industries, from automotive and aerospace to electronics and pharmaceuticals. In today's rapidly evolving global economy, advanced manufacturing plays a crucial role in driving innovation, increasing productivity, and maintaining competitiveness.One key aspect of advanced manufacturing is the integration of automation and robotics into production processes. By employing automated systems, manufacturers can streamline operations, reduce labor costs, and improve product quality and consistency. Robotics, in particular, enables precise and repetitive tasks to be performed with unmatched accuracy and speed, leading to higher throughputand lower error rates.Furthermore, advanced manufacturing techniques often involve additive manufacturing, commonly known as 3D printing. This revolutionary technology enables the creation of complex components and structures layer by layer, using a variety of materials ranging from plastics to metals. Additive manufacturing offers significant advantages over traditional subtractive methods, such as CNC machining, including reduced material waste, faster prototyping, and greater design flexibility.Another key enabler of advanced manufacturing is the Internet of Things (IoT), which refers to the network of interconnected devices and sensors that collect and exchange data in real-time. By harnessing the power of IoT, manufacturers can monitor equipment performance, optimize production processes, and predict maintenance needs, thereby minimizing downtime and maximizing efficiency.Moreover, advanced manufacturing relies heavily on advanced materials with unique properties andcharacteristics. These materials, such as carbon fiber composites and high-strength alloys, offer superiorstrength-to-weight ratios, corrosion resistance, andthermal conductivity, making them ideal for demanding applications in aerospace, defense, and beyond.In addition to technological advancements, advanced manufacturing also requires a skilled workforce capable of operating and maintaining complex machinery, analyzing data, and implementing continuous improvement initiatives. As such, education and training programs play a vital role in preparing the next generation of manufacturingprofessionals for the challenges and opportunities of the future.In conclusion, advanced manufacturing represents a paradigm shift in the way goods are produced, leveraging technology, innovation, and talent to drive efficiency, quality, and competitiveness. By embracing advanced manufacturing principles and practices, companies can stay ahead of the curve and thrive in today's dynamic and ever-changing marketplace.先进制造。
机械类外文文献翻译(中英文翻译)
机械类外文文献翻译(中英文翻译)英文原文Mechanical Design and Manufacturing ProcessesMechanical design is the application of science and technology to devise new or improved products for the purpose of satisfying human needs. It is a vast field of engineering technology which not only concerns itself with the original conception of the product in terms of its size, shape and construction details, but also considers the various factors involved in the manufacture, marketing and use of the product.People who perform the various functions of mechanical design are typically called designers, or design engineers. Mechanical design is basically a creative activity. However, in addition to being innovative, a design engineer must also have a solid background in the areas of mechanical drawing, kinematics, dynamics, materials engineering, strength of materials and manufacturing processes.As stated previously, the purpose of mechanical design is to produce a product which will serve a need for man. Inventions, discoveries and scientific knowledge by themselves do not necessarily benefit people; only if they are incorporated into a designed product will a benefit be derived. It should be recognized, therefore, that a human need must be identified before a particular product is designed.Mechanical design should be considered to be an opportunity to use innovative talents to envision a design of a product, to analyze the systemand then make sound judgments on how the product is to be manufactured. It is important to understand the fundamentals of engineering rather than memorize mere facts and equations. There are no facts or equations which alone can be used to provide all the correct decisions required to produce a good design.On the other hand, any calculations made must be done with the utmost care and precision. For example, if a decimal point is misplaced, an otherwise acceptable design may not function.Good designs require trying new ideas and being willing to take a certain amount of risk, knowing that if the new idea does not work the existing method can be reinstated. Thus a designer must have patience, since there is no assurance of success for the time and effort expended. Creating a completely new design generally requires that many old and well-established methods be thrust aside. This is not easy since many people cling to familiar ideas, techniques and attitudes. A design engineer should constantly search for ways to improve an existing product and must decide what old, proven concepts should be used and what new, untried ideas should be incorporated.New designs generally have "bugs" or unforeseen problems which must be worked out before the superior characteristics of the new designs can be enjoyed. Thus there is a chance for a superior product, but only at higher risk. It should be emphasized that, if a design does not warrant radical new methods, such methods should not be applied merely for the sake of change.During the beginning stages of design, creativity should be allowedto flourish without a great number of constraints. Even though many impractical ideas may arise, it is usually easy to eliminate them in the early stages of design before firm details are required by manufacturing. In this way, innovative ideas are not inhibited. Quite often, more than one design is developed, up to the point where they can be compared against each other. It is entirely possible that the design which is ultimately accepted will use ideas existing in one of the rejected designs that did not show as much overall promise.Psychologists frequently talk about trying to fit people to the machines they operate. It is essentially the responsibility of the design engineer to strive to fit machines to people. This is not an easy task, since there is really no average person for which certain operating dimensions and procedures are optimum.Another important point which should be recognized is that a design engineer must be able to communicate ideas to other people if they are to be incorporated. Communicating the design to others is the final, vital step in the design process. Undoubtedly many great designs, inventions, and creative works have been lost to mankind simply because the originators were unable or unwilling to explain their accomplishments to others. Presentation is a selling job. The engineer, when presenting a new solution to administrative, management, or supervisory persons, is attempting to sell or to prove to them that this solution is a better one. Unless this can be done successfully, the time and effort spent on obtaining the solution have been largely wasted.Basically, there are only three means of communication available tous. These are the written, the oral, and the graphical forms. Therefore the successful engineer will be technically competent and versatile in all three forms of communication. A technically competent person who lacks ability in any one of these forms is severely handicapped. If ability in all three forms is lacking, no one will ever know how competent that person is!The competent engineer should not be afraid of the possibility of not succeeding in a presentation. In fact, occasional failure should be expected because failure or criticism seems to accompany every really creative idea. There is a great deal to be learned from a failure, and the greatest gains are obtained by those willing to risk defeat. In the final analysis, the real failure would lie in deciding not to make the presentation at all. To communicate effectively, the following questions must be answered:(1) Does the design really serve a human need?(2) Will it be competitive with existing products of rival companies?(3) Is it economical to produce?(4) Can it be readily maintained?(5) Will it sell and make a profit?Only time will provide the true answers to the preceding questions, but the product should be designed, manufactured and marketed only with initial affirmative answers. The design engineer also must communicate the finalized design to manufacturing through the use of detail and assembly drawings.Quite often, a problem will occur during the manufacturing cycle [3].It may be that a change is required in the dimensioning or tolerancing of a part so that it can be more readily produced. This fails in the category of engineering changes which must be approved by the design engineer so that the product function will not be adversely affected. In other cases, a deficiency in the design may appear during assembly or testing just prior to shipping. These realities simply bear out the fact that design is a living process. There is always a better way to do it and the designer should constantly strive towards finding that better way.Designing starts with a need, real or imagined. Existing apparatus may need improvements in durability, efficiently, weight, speed, or cost. New apparatus may be needed to perform a function previously done by men, such as computation, assembly, or servicing. With the objective wholly or partly defined, the next step in design is the conception of mechanisms and their arrangements that will perform the needed functions.For this, freehand sketching is of great value, not only as a record of one's thoughts and as an aid in discussion with others, but particularly for communication with one's own mind, as a stimulant for creative ideas.When the general shape and a few dimensions of the several components become apparent, analysis can begin in earnest. The analysis will have as its objective satisfactory or superior performance, plus safety and durability with minimum weight, and a competitive east. Optimum proportions and dimensions will be sought for each critically loaded section, together with a balance between the strength of the several components. Materials and their treatment will be chosen. These important objectives can be attained only by analysis based upon the principles ofmechanics, such as those of statics for reaction forces and for the optimumutilization of friction; of dynamics for inertia, acceleration, and energy; of elasticity and strength of materials for stress。
先进制造技术中英文翻译
外文资料翻译附1、外文原文（复印件）Advanced Manufacturing Techndogylimitations on acceptable feed rates-determined by the ability of the cutting t∞l to withstandincreased cutting loads without fracture.Increasing radial cutting depths also could increase removal rates, although cutting depth is often determined by the amount of stock removal required. As in the case of increased feedrates, IOol life decreased with increased depth of cut. As expected t a tradeoff exists between t∞llife and removal rate.generated in every Inetal removal process： tangential There are three forforce, generated by the part rotation; radial force, generated by the resistance of the workpiecematerial to depth of cut; and, lastly, longitudinal force, generated by the feed rate applied. Theseforces are 30% to 80% greater than in “soft" machining processes. For example f when comparingpreheat-treated to heat-treated steel with a hardness of 62 HRC, the longitudinal force increasesfrom 30% to 50% ∙ Thetangential force increases 30% to 40% f and the radial force increases from 70% to 1CK)% ∙Therefore, the machine tool must be able to handle the increased cutting forces t especially in theradial direction.Cutting c∞lant can influence the generation of white layer. Because white layer is thought to occur as the result of a phase transformation on the surface, cutting c∞1ant might helpeliminate thermal damage by keeping the workpiece surface c∞L So<ne reports say cuttingc∞lant eliminates white layer, but other studies show c∞!ant having no effect. T∞l condition isalso believed to be an important factor, with new t∞ls producing undamaged surfaces, whilewhite layer increases with increasing t∞l wear.If hard turning is to replace finish grinding operations, it must be capable of ProdUCing surface finishes comparable to those generated by grinding. Unlike grinding, where surface finishis deteπnined by the size, shape, hardness> and distribution of abrasive grains in the grindin gwheel, hard-turned surfaces are nominally defined by the geometry of the cutting process,primarily by the cutting t∞Γs feed rate and nose radius.For grinding cylindrical applications, both the wheel and the woriφiece must rotate.Moreover, the wheel rotates rapidly while the workpiece rotates slowly. If the rotating membersare imperfectly concentric, the combination of imperfections and ∏)lational speed differentialproduces lobing. A geometric OUl-Of-round pattern on the workpiece is produced t which canaffect the end-product performance. With hard turning t on the other hand l either the workpieceor cutting t∞l is rotated, not both.Z7∏5Therefbre, the machined surface will be as accurate as the machine tool spindle and the longitu dinal direction Ot the machine t∞l relative to the center line of the machine.Another disadvantage with grinding is the generation of tremendous surface heat at the point of contact between the grinding wheel and the workpiece. Even when flood cwlant is properly applied, workpiece surface stress risers and heat checks can occur, which can lead to premature failure of the ground part in service. With hard turning, less heat is generated t and if properly applied, the heat that is generated will be carried away with the brittle material removed. Thus, the finished parts are produced without stress risers or heat checks.Another major advantage of HFM is that conventional turning machines can be used with workpieces as hard as 65 HRC using commercially available ceramic inserts. Savings occur in two areas, processing and capital investment. In processing, the machining t setup, and t∞l changing time are significantly reduced. Grinding wheel changing, on the other hand, is time-consuming. Guards must be removed, along with the spindle locking nuts, the worn wheel must be changed, and the new wheel balanced and dressed. Wheel changing can take as much as IOO times longer than changing ceramic inserts, which require only simple indexing or replacement in the holder.Equipment also is less expensive. A turning machine costs significantly less than a production grinder to do comparable work. As already mentioned, setup is easier and quicker. Turning machines also are simpler in ∞nstruction-there are no reciprocating slides to wear, maintain, or replace-for easier maintenance. However, the strength and rigidity of every component in the machine must be adequate to handle the additional cutting forces.3.7.2 Hard MillingOne machining advancement that has taken hold over the past few years is hard milling. Typically mold and die makers perform hard milling to cut P∙20, H-13 and other tool steels.These materials range in hardness from 45 to 64 HRC and are traditiona]ly electrical discharge machined. But new technologies make hard milling a viable alternative. Successful hard milling requires several components to ∞me together一the machine tool, t∞lholders f cutting IoolSg CAD/CAM system and pr how.S u know-… -------------------- Advanced MamArturing Technology Ho VV —1> Machine FactorsThe machine t∞l is the most significant component. The m aspect of the machine tool is that it must be designed for hard milling and have the samecharacteristics found in a high-speed machining center. The machine t s base ∞nstιυction andindividual components, such as the drive train, spindle and CNC, must be capable of handling thedemands of hard milling.The base ∞nstruction must be extremely rigid and have a high degree of damping abilities.These characteristics are found in machine tools with bases ∞nstructed from polymer concrete.These machines typically have six to 10 times the damping characteristics of machines with castiron bases. Additionally, polymer ∞ncrete has excellent mechanical and theππal characteristics.The machine t∞Γs drive train should in∞rporate digital drive technology for optimalacceleration and de celeration. This technology allows the CNC to perfbπn a high degree ofcontouring accuracy and gives it excellent dynamics capabilities.One of the most overlooked components is the spindle. The spindle must be able to providea great deal of flexibility, offering high torque at low spindle speeds and maximum power for alarge range of spindle speeds. An ideal spindle t s speed ranges from 100 rpm to 20f 000 rpm orhigher, depending on the application. Hybridceramic bearings in the construction of the spindle increase spindle Stiffil andtemperature stability. Figure 3.14 shows a 5-axis milling machine designed forhard milling, which has a similar requirements as high-speed machining.Figure 3.14 Mikron 1S HSM 5-axis machine.fundamental,accuracyOne of the main ∞ntributors to successful hard milling is the cutting tool. Fbr roughing hardened materials9 end mills with four or more flutes arc recommended. These provide small chip loads while having the capability to cut at higher feed rates.The cutting took should be short with short flute lengths and have a helix angle of approximately 300. A 30o helix has proven to be optimal for chip flow and dispersal of heat.The carbide substrate should also be ∞nsidered. Only caιbide t∞ls with fine or ultra-fine grain sizes9about 0.5μm to0.6 μm , should be used. These tools provide increased edge strength and reduce built-up edge.For milling larger hardened cavities and cores, cutting t∞ls with inserts should be considered. Carbide inserts are less expensive than solid-caΛide end-mills, and by indexing the insert, tool life can be extended. However, these t∞ls are typically not designed for high spindle speeds. There is also a significant safety risk if improperly handled.Hard milling puts a great amount of stress on the cutting tool from high heat and abrasive wear. To help overcome these stresses, coated cutting t∞Js must be used. Coatings offer a protective layer on the IoOI, substantially increasing t∞l life.Coating selection should be made based on individual properties. Titanium-based coatings, such as TiCN and TiAlN, are the most common for hard milling. The wear resistance, or its Iianlness l is the most important property of TiCN, while TiAlN resists heat and oxidation better. The t∞lmaker may further enhance its coatings by offering unique multilayer blends.Flood c∞lant is not commonly used in hard millin g. Hard milling often generates tremendous amount of heat, which is transferred into the chips and causes the c∞lant to vaporize as it hits the hot chips. The use of ∞olant can also create thermal instability with the cutting t∞l.Compressed air is used to help displace chips during cutting› Additionally, a ∞mbination of oil and mist is often selected. Oil helps reduce friction, thereby increasing tool life and improving surface finish. When using oil and mist, an extraction unit should be integrated into the machine t∞l to help remove the oil from the air.2.CAD/CAM AnalysisThe CAD/CAM system is another important component. CAD/CAM systems have gready advanced over the years, and now provide a variety of advanced featuresAdvanced Manufacturing TechncJogy118 ∖∖and capabilities. However t not all systems are created equal and there are still many (hat do not have the capabilities to create t∞l paths for hard nulling .Although no CAD/CAM system is designed exclusively for hard milling, many of the systems that offer HSMing capabilities have the same strategies for hard milling because the two are related. When hard milling t strategies that keep the cutting tool in motion should be used. This ensures the t∞l is ∞ntinuously cutting with a constant chip load, which is one of the more desirable conditions to maintain when hard milling.Before tool paths can be applied, a complete analysis of the part must be performed. Not all parts are suitable for hard milling. The specific areas to be machined should be clearly identified, determining the smallest internal radius and largest working depth. A tool with a 4：1 length-to-diameter ratio commonly does not pose any problems.Problems arise when the ratio grows. When ratios are excessive t hard milling experience plays an important role in deteπnining how successful one is. Hard milling with small diameter cutting tools are possible as long as care is taken to maintain a ∞nstant chip load and machine at minimal LXXs.If a CAD/CAM system does not have the t∞ls to verify or simulate the NC code directly, there are numerous software packages on the market that can.Finally, proper know-how is vital to successful hard milling. AD of the necessary components are of no use without knowledge of the processing procedures ∙ Successful hard milling is based on specific know-how, advanced knowledge HSMing t proper choice of cutting t∞ls and clamping systems, and using a HSM- capable CAD/CAM system.A clear understanding of all the components provides better awareness of what is needed to be successful at hard milling.3.Precision MachiningPrecision machining is any process using a cutting tool, whether turning, milling, or grinding, which forms a precise dimension, form, and finish of surface. The accuracy held must be 10 μm or less. Any operation resulting in less accuracy is generally ∞nsιdcred ∞nventional machining.Compared to standard machining of traditional materials (steel, Al) f successful precision machining of hard materials is more sensitive to parameters such as machine IoOl accuracy, stiffness, toolholder design t cutting t∞l material and geometιy,fixtυring, c∞)ant presentation, and machining technique.The properties that make hard materials attractive for commercial use also make them extremely difficult to machine to the tolerances required by advanced applications.Obtaining tighter tolerances on hard materials is a challenge that must be met if manufacturers are to achieve the improved performance; it f s also where the future of manufacturing lies.A major factor that influences the production of close-tolerance parts from hard materials is the machine tool itself and its parameters, including inherent repeatability, accuracy, stiffness, and the sm∞thness or uniformity of travel t spindle speed, thermal stability, machine protection f control capabilities, etc.Virtually any machine t∞l Can produce some close-tolerance parts if the feed rate is reduced and the cutting t∞I changed frequently. To SUCCeSSftIIIy produce precision components to meet market demands, however, the machining operation must be cost-effective, as well as accurate and repeatable.A key design factor in machine t∞ls is the rigidity or stiffness of the cutting t∞l to the workpiece. Obviously, components and subassemblies must also have high stiffness. Machine stiffness is a major contributing factor to overall machine accuracy and performance. Stiffness is measured by the deflection of an element of the machine when it's subjected to a load.Machine accuracy is another critical design parameter. To have the confidence to cut high-precision parts on a production basis, ifs necessary that the user know the 3-D accuracy of the machine t∞l.The same criteria apply to t∞lholders. They too must provide precision, rigidity f and repeatability to produce close-tolerance parts, and to do so they must be kinematically correct.Cutting tools are another element that ProdUCe a major effect on the production of precision parts from hard materials. Parameters to be considered are： material, design, fabrication t tolerance, cost, and availability.Tool life is an economic issue that must be considered when machining precision parts from hard materials. While it may perfoπn well, a tool that you must change after every IOO mm of cut length is nυ( an economical so lution to machining these materials. T∞l life depends UPon the materia] to be machined and the process.Workholding is another key element. Material considerations are important.2、外文资料翻译译文先进制造技术尽管裁断的深度是由材料去除率的总额决定的，增加径向的裁断深度同样能够增加磨损率。
世界最新机械设计理念外文文献翻译、中英文翻译、外文翻译
附件1：外文原文The world's Latest Mechanical Design ConceptsAbstract: According to scholars at home and abroad to carry out mechanical design product design features of the main ideas, product design method of the program summarized as systematic, modular structure, based on product characteristics of knowledge and wisdom. The characteristics of these methods and their organic connection between them and put forward to achieve the computer product design direction.Key words: Mechanical Product Design Method Development TrendsDesign documents will be Semantic Web as a design tool in the design of its Semantic Web activity of the development of ASK, using nodes and lines to describe the design a network, nodes that components of the cell (such as design tasks, functions, components or processing equipment, etc. ), used to adjust the lines and definitions between nodes of different semantic relations, thus the design process all the activities and results of pre-built models so that the definition of the early design requirements to the specific description of each structure can be defined by the relationship between the expression, achieved a computer-aided design process, the leap from the abstract to the concrete.A systematic design methodThe main features of a systematic design method are: the design as designed by a number of elements of a system, the independence of each design elements, each element of an organic link between the existence of, and is layered, with all the design elements , you can design systems to achieve the required task.Systematic design idea in the 70's by the German scholar Professor Pahl and Beitz, the system based on the theory they developed a general pattern of the design, advocacy design work should have organized. German Engineers Association, on the basis of this design concept to develop a standard VDI2221 technology systems and product development design methods.1. The user needs functional characteristics as a product concept, structure design and part design, process planning, job control, etc. based on the macro from the productdevelopment process of starting the use of quality function deployment method and system to user demand information reasonably and efficiently converted to the various stages of product development, technical goals and operational control procedures method.2. The level of the product life of the organism as a system, and means of living systems theory, the product design process can be divided into successful hierarchy of needs to achieve the functional requirements of the conceptual level and product level of the specific design. At the same time life-support systems used to express the abstract icons of the product functional requirements, system structure formation of product features.3. The mechanical design of the application of systems science into two basic questions: First, to be designed as a system dealing with the products, the best way to determine its component parts (modules) and their mutual relations; 2 is the product design process as a a system, according to design objectives, a correct and reasonably determine the various aspects of the design work and various design stage.Because each designer's point of research questions and to consider the question of emphasis, to design a specific research methods used is also different. Here are some representative of the systematic design methods.4. Design Element MethodWith the five design elements (functions, effects, effects vector, shape, elements, and surface parameters) describe the "product solutions" that a product to determine the value of the five design elements, the product of all the features and characteristics of the value of i.e. determined. Scholars in China have adopted similar methods designed to describe the product's original understanding.5. Graphic modeling methodAnd developed a "design analysis and guidance systems" KALEIT, with the level of clear graphic description of a product's functional structure and its associated abstract information, to the system structure and function relationship of graphical modeling, and functional connection between the layers [ 2].Assistance will be designed to be divided into two aspects of methodology and exchange of information using the Nijssen Information Analysis Method can be usedgraphic symbols, with a rich semantic model structure, can be described as integration conditions, can be divided into types of constraints can be achieved in relations between any combination of characteristics , the design method to solve integration and information technology to realize the design process of information between different abstraction layers between the graphical modeling.6. "Concept" - "Design" methodProduct's design is divided into "concept" and "design" in two stages. "Concept" phase of the task is to find, choose and mix to meet the requirements of the original understanding of design tasks. "Design" stage of work is a concrete realization of the original understanding of the conceptual stage.Of the program's "idea of" specific described as: In accordance with the appropriate functional structure, seeking to meet the design requirements of the original understanding of the task. The functional structure of the sub-function is performed by the "structural elements" to achieve, and "structural elements" of the physical connection between the definition of a "feature vector", "feature vector" and "structural elements" further the interaction between the formation of the functional diagram ( mechanical diagram). The program "design" is based on functional diagram, the first qualitative description of all of the "feature vector" and "structural elements", and then quantitatively describe all the "structural elements" and the connection parts ( "feature vectors"), the shape and location to be structure diagram [3]. Roper, H. using graph theory, by means of which he defines as the "total design unit (GE)", "structural elements (KE)", "functional structural elements (FKE)", "connect structural elements (VKE)", "Structural Parts (KT)", "structure element part (KET)" concepts, as well as describe the structure element size, location, and transmission parameters of the interactions between a number of kinds of schematics, the intuitive design professionals have done a formal design method a description of the formation of an effective application of existing knowledge, methods, and applied to "ideas" and "design" stage.7. Bond Graph MethodFunction of the composition of system components will be divided into produce energy, consumed energy, changing energy forms, such as various types of energy transfer, and to use bond graphs to express the function component solution, hoping tofunction-based model and bond graph combine to achieve functional structure the automatic generation and functional structure with the bond graph automatic conversion between the search for bond graph generated by a number of design methods.To promote the product on the basis of functional analysis, the product has some features broken down into one or several modular basic structure, by selection and combination of the basic structure of these modular form into different products. These basic structures can be parts, components, or even a system.The structure should have a standardized interface (connection and co-operation department), and is serialized, universal, integrated, hierarchical, agile, economic-oriented, with interchangeability, compatibility and relevance. China's combination of software component technology and CAD technology, variant design combined with the modular design, according to modular principle of classification, will be divided into descending Machining Center Machine Tool product level, component level, component level and component level, and use expert knowledge and CAD technology to combine them into different species, different specifications of functional blocks, and then by the combination of these functions into different modules of the overall program processing center.To design a directory as an alternative variation of the mechanical structure of the tool, the solution proposed by the design elements of a complete, structured layout, the formation of the solution set design catalogs. And in the solution set designed to comment on each one listed in the directory solution additional information, is very beneficial to design engineers select solution elements.The vigorous development of network technology, collaborative design and manufacturing, as well as the product from the user's functional requirements → design → processing → assembly → finished product of this realization of concurrent engineering possible. However, an important prerequisite to achieve these goals one of the conditions is to realize the effect of product design three-dimensional visualization. To this end, three-dimensional graphics software, more and more intelligent design software programs used in the product design, virtual reality technology and multimedia, hypermedia tools for product design is also its first debut. At present, Germany and other developed countries are focused on research hypermedia technology, product dataexchange standard STEP, as well as standard virtual reality modeling language based on a standard exchange format for virtual environments) in the product design applications.Mechanical product design is moving in computer-aided realization of intelligent design and to meet the needs of distributed collaborative design and manufacture of direction, due to the computer product design Study on the implementation started late, not yet mature, to achieve the above objectives program design tools [4]. Author believes that the integrated use of paper, four types of design method is an effective way to achieve this goal. Although the integrated use of these methods are more involved in the field, not only with the mechanical design of the field-related knowledge, but also to the systems engineering theory, artificial intelligence theory, computer hardware and software engineering, network technology areas such as domain knowledge, it is still product design must be working for. Abroad in research in this area has achieved initial success, our scholars have been aware of CAD design technology and the importance of international exchange and cooperation, and its measures to be taken.Feature-based design methodology of knowledge The main features are: using a computer can identify the language to describe the characteristics of the product and its design experts in the field of knowledge and experience to establish the appropriate knowledge base and inference engine, re-use of stored domain knowledge and the establishment of the inference mechanism to bring computer-aided product design.The mechanical system design is mainly based on the characteristics of a product, and design experts in the field of knowledge and experience to push volume and decision-making, the completion of body type, the number of synthesis. To achieve this stage of computer-aided design, must study the automatic acquisition of knowledge, expression, integration, coordination, management and use. To this end, the design and scholars at home and abroad program for the mechanical system design knowledge of the automated processing done a lot of research work, the approach can be summarized into the following several.附件2：外文资料翻译世界最新机械设计理念摘要：根据目前国内外设计学者进行机械产品设计时的主要思维特点，将产品方案的设计方法概括为系统化、结构模块化、基于产品特征知识和智能。
机械外文翻译文献翻译--现代设计与制造
机械外文翻译文献翻译--现代设计与制造中文4935字Modern Design and Manufacturing一、The Computer and ManufacturingThe computer is bringing manufacturing into the Information Age. This new tool, long a familiar one in business and management operations, is moving into the factory, and its advent is changing manufacturing as certainly as the steam engine changed it 100 years ago.The basic metalworking processes are not likely to change fundamentally, but their organization and control definitely willIn one respect, manufacturing could be said to be coming full circle. The fist manufacturing was a cottage industry: the designer was also the manufacturer, conceiving and fabricating products one at a time. Eventually, the concept of the interchangeability of parts was developed, production was separated into specialized functions, and identical parts were produced thousands at a time .Today, although the designer andmanufacturer may not become one again, the functions are being drawn close in the movement toward an integrated manufacturing system.It is perhaps ironic that, at a time when the market demands a high degree of product diversification, the necessity for increasing productivity and reducing coats is driving manufacturing toward inegration into a coherent system, a continuous process in which parts do not spent as much as 95% of production time being moved around or waiting to be worked on .The computer is the key to each of these twin requirements. It is the only tool that can provide the quick reflexes, the flexibility and seed, to meet a diversified market. And it is the only tool that enables the detailed analysis and the accessibility of accurate data necessary for the integration of the manufacturing system.It may well be that, in the future, the computer may be essential to a company’ssurvial. Many of today’s businesses will fade away to be replaced by more-productive combinations. Such more-productive combinations are superquality, superproductivity plants. The goal is to design and operate a plant that would produce 100% satisfactory parts wich good productivity.A sophisticated, competitive world is requiring that manufacturing begin to settle for more, to become itself sophisticated. To meet competition, for example, a company will have to meet the somewhat conflicting demands for greater product diversification, higher quality, improved productivity , higher quality, improved productivity and prices.The company that seeks to meet these demands will need a sophisticated tool, one that will allow it to respond quickly to customer needs while getting the most out of its manufacturing resources.The computer is that tool.Becoming a “superquality,superproductivity” plant requires the integration of an extremely complex system .This can be accomplished only when all extremely complex system. This can be accomplished only when all elements of manufacturing-design, fabrication and assembly, quality assurance, management, materials handing-are computer integrated.In product design, for example, interactive computer-aided-design(CAD) systems allow the drawing and analysis tasks to be performed in a fraction of the time allow the drawing and analysis tasks to be performed in a fration of the time previously required and greater accuracy. And programs for prototype testing testing and evaluation further speed the design process.In manufacturing planning, computer-aided process planning permits the selection, from thousands of possible sequences and schedules,of the optimum process.On the shop floor, distributed intlligence in the form of microprocessors controls, runsautomated loading and unloading equipment, and collects data on current shopconditions.But such isolated revolutions are not enough. What is nended is a totally automated system, linked by common software from front door to back.Essentially, computer integration provides widely and instantaneously available, accurate information, improving communication between departments, permitting tighter control, and generally enhancing the overall quality and efficiency of the entire system.Improved communication can mean, for example, designs that are more producible. The NC programmer and the tool designer have a chang to influence the product designer, and vice versa.Engineering changes,can be reduced,and those that are required can be handled more efficiently.Not only dose the computer permit them to be specicified more quickly, but it also alers subsequent users of the data to the factthat a change has been made.The instantaneous updating of production-control data permits better planning and more-effective scheduling . Expensive equipment, therefore, is used more productively, and parts move more efficiently through production, reducing work-in-process coats.Product quality, too, can be improved. Not only are more-accurate designs produced, for example,but the use of design data by the quality-assurance department helps eliminate errors due to misunderstandings.People are enabled to do their jobs better.By eliminating tedious calculations and paperwork—not to mention time wasted searching for information—the computer not only allows workers to be more productive but also frees them to do what only human being can do: think creatively.Computer integration may also lure new people into manufacturing. People are attracted because they want to work in a modern,technologically sophisticated enviroment.In manufacturing engineering, CAD/CAM decreases tool-design,NC-programming, and planning times while speeding the response rate, which will eventually permit in-hous staff to perform work that is currently being contracted out.二、Numerical ControlOne of the most fundamental concepts in the area of advanced mannufacturing technologies is numerical control(NC). Prior to the advent of NC, all machine tools were manually operated and controlled. Among the many limitations associated with manual control machine tolls. Perhaps none is more prominent than the limitation of operator skills. With manual control, the quality of the peoduct is directly related to and limited to the skills of the operator. Numerical control represents the first major step away from human control of machine tools.Numerical control means the control of machine tools and other manufacturing systems through the use of prerecorded, written symbolic instrutions. Rather than operating a machine tool, an NC technician writes a program that issues operating a machine tool, an NC technician weites a program that issues operational instructions to the machine tool.Numerical control was developed to overcome the limitation of human operators, and it has done so. Numerical control machines are more accurate than manually operated machines,they can produce parts more uniformly, they are fastre, 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 manuallyoperated predecessors. An NC machine tool can automatically produce a wide variety of parts, each involving an assortment of widely varied and complex machining processes. Numerical control has allowed manufacturers to undertake the production of products that would not have been feasible form 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.The APT(Automatically Programmed Tools)language was designed at the Servomechanism laboratory of MIT in 1956. This is a special programming language for NC that uses statements similar to English language to define the part geometry, describe the cutting tool configuration, and specify the necessary motions. The development of the APT languagewas a major step forward in the further development of NC technology. The original NC systems were vastly different form those used today. The machines had hardwired logic circuits. The instructional programs were written on punched paper, which was later to be replaced by magnetic plastic tape. A tape reader was used to interpret the instructions written on the tape for the machine. Together, all of this represented a giant step forward in the control of machine tools. However, there were a number of problems with NC at this point in its development.A major problem was the fragility of the punched paper tape medium. It was common for the paper tape containing the programmed instructions to break or tear during a machining process. This problem was exacerbated by the fact that each successive time a part was produced on a machine tool, the paper tape carrying the programmed instuctions had to be rerun through the reader. If it was necessary toproduce 100 copies of a given part, it was also necessary to run the paper tape through the reader 100 separate times. Fragile paper tapes simply could not withstand the rigors of a shop floor environment and this kind of repeated use.This led to the development of a special magnetic plastic tape. Whereas the paper tape carried the progtammed instructions as a series of holes punched in the tape, the plastic tape carried the instructions as a series of magnetic dots. The plastic tape was much stronger than the paper tape, which solved the problem of frequent tearing and breakage. However, it still left two other problems.The most important of these was that it was difficult or impossible to change the instructions entered on the tape. To make even the most minor adjustments in a program of instuctions,it was necessary to interrupt machining operations and make a new tape. It was also still necessary to run the tape though the reader as many times as there were parts to be produced. Fortunately,computer technology became a reality and soon solved the problems of NC asociated with punched paper and plastic tape.The devslopment of a concept known as direct numerical control(DNC) solved the paper and plastic tape problems associated with numerical control by simply eliminating tape as the medium for carrying the programmed instructions. In direct numerical control, machine tools are tied, via a data transmission link, to a host computer. Programs for operating the machine tools are stored in the host computer and fed to the machine tool 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 limitations as all technologies that depend on a host computer. When the hoet computer goes down, the machine tools also experience downtime. This problem led to the development of computer numerical control.The development of the microprocessor allowed for the development of programmable logic controllers (PLCs) and microcomputers. These two technologies allowed for the development of computer of computer numerical control (CNC). Whit CNC, each machine tool has a PLC or a microcomputer that serves the same purpose. This allows programs to be input and stord at each individual machine tool. It also allows programs to be devsloped off-line and downloaded at the individual machine tool. CNC solved the probiems associated with 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 connect microcomputers for better data management.三、ProgrammersSkillful part-programmers are a vital requirement for effective utilization of NC machine tools. Upon their efficiency of those machines and the financial payback of the significant investment in the machines themselves, the piant’s NC-support facilities, and the overhead costs involved.Skillful NC part-programmers are scarce. This reflects not only the general shortage of experienced people in the meyalworking industries but also the increasing demand for programmers as industry turns more to the use of numerically controlled machines to increase the capability, versaility, and productivity of manufacturing.On an industry-wide basis,the obvious answer is to create new programmers by training them-and there are a number of sources for such training. But first,what qualifications should programmers have, and what must programming trainees learn?According to the National Machine ToolBuilder’s Assn booklet “Selecting an Appropriate NC programming Method,”the principal qualifications for manual programmers are as follows:Manufacuring Experience Programmers must have a thorough understading of the capabilities of the NC machines being programmed, as well as an understanding of the basic capabilities of the other machines in the shop. They must have an extensive knowledge of, and sensitivity to, metalcutting principles and practices and practices, cutting capabilities of the tools, and workholding fixtures and techniques. Programmers properly trained in these manufacturing-engineering techniques can significantly reduce production costs.Spatial Visualization Programmers must be able to visualize parts in there dimensions, the cutting motions of the machine, and potential interferences between the cutting tool, workpiece, fixture, or the machine itself.Mathematics A working knowledge ofarithmetic, algebraic, trigonometric, and geometric operations is extremely important. A knowledge of higher mathematics, such as advanced algebra, calculus,etc, is not normally required.Attention to Details It is essential that programmers be acutely observant and meticulously accurate individuals. Programmers errors discovered during machine setup can be very expensive and time-consuming to correct.“Manual programmer,”the booklet nots elsewhere, “requires the programmer to have more-detailed knowledge of the machine and contril, maching practices, and methods of compution than dose computer-aided programming. Computer-aided programming, on the other hand, requires a knowledge of the computer programming language and the computer system in order to process that language. In general, manual programmer is more tedious and demanding because of the detail involved. In a computer –aidedprogramming system, this detail knowledge is embodied in the computer system(processor, postprocessor, etc).”Experts in the NC and training fields typically agree on these qualifications and requirements-adding such subsidiary details as a knowledge of blueprint reading, machinability of different metals, use of shop measuring instruments, tolerancing methods, and practices.Where should you look for candidates? First of all, in your own plant-out on the shop floor. Edward F. Schloss, a Cincinnati Milacron sales vice president, puts it this way: “We’ve had excellent success with good lathe operators and good boring-mill hands. They don’t know it, but they’ve been programming most of their working lives, and they know basic shop math and trigonometry. You can teach them programming rather handily. Conversely, though, it’s fairly hard to make NC part-programmers out of high-powered mathematicians. The path programming is easy.But what to do with it-the feeds, speeds, etc. –that may take even more-extensive training.”With more-powerful computer-assist programming, the need for metalcutting knowledge on the part of programmers is reduced. Through the use of this software, Cincinnati Milacron has been very successful in hiring nem college graduates, includeing some with nontechnical degrees, and training them to be NC part-programming. The trainees are given hands-on machine-tool experience in the plant before they are advanced to programming.All suppliers of NC machine tools, of course, provide some sort of training in the proramming of their products, and most offer formalized training programs, Milacron’s sales department, for example, has 20 fulltime customer-training instructors. The company’s prerequisites for programmer training include the following: “Participants must have knowledge of general machine-shop safety procedures and be able to read detail drawings, sectional views, and NCmanuscripts. ”“Knowledge of plane geometry, right-angle trigonometry, and fundamentals of tolerancing is required.”“Knowledge of NC manual part-programming, NC machine-tool setup and operating procedures, part processing, metalcutting technology, tooling, and fixturing is also needed.”Sending people with that kind of background to school will ensure that users of the NC machine will get the maximum benefit for their training dollar the cost of a week of the trinee’s time, travel, and living expenses, even though the training fee is waived with the basic purchase of the machine tool.现代设计与制造一、计算机与制造业：计算机正在将制造业带入信息时代。
机械制造业外文翻译外文文献英文文献制造业中的新技术制造业面临的挑战
N e w T e c h n o l o g i e s i n M a n u f a c t u r i n gT h e C h a l l e n g e o f m a n u f a c t u r i n gTh e n e e d for q u a l i fi e d m a n u fa c tu r i n g e n g i n e e r s h a s n e ve r b e e n g r e a t e r . To m e e t tod a y ’s ch a l le n g e s , i t i s n e ce s s a r y to g a i n a b r oa d b a ck g r ou n d i n b oth m a t e r i a l s c i e n ce s , d e s i g n , a n d m a n u fa c tu r in g p r oce s s e s . Con s id e r a b le e m p h a s i s i s a l s o b e in g p l a ce d on com p u te r s c i e n ce s a n d a u tom a t i c con t r ols .Th e m a n u fa c tu r i n g e n g i n e e r m a s t b e a b l e to v i s u a l i ze th e w h o le p r ob l e m of p r od u ct i on i n th e cor r e c t p e r s p e c t i ve fr om th e b a s i c com p on e n t m a te r i a l s a n d toolin g th r ou g h th e s te p b y s te p op e r a t i on a l p l a n n in g , fin a l a s s e m b l y , i n s p e c t ion , a n d s h i p m e n t .Th e m a n u fa c tu r in g e n g in e e r i s r e s p on s i b le for th e e x p e n d i tu r e of l a r g e s u m s of m on e y for toolin g a n d m a ch i n e r y to k e e p p r od u c t i on on a com p e t i t i ve b a s i s . H e n ot on l y s h ou ld b e fa m i l i a r w i th th e th e or e t i ca l a s p e c t s of fa b r i ca t i on , b u t a l s o m u s t b e a b l e to w or k ou t p r a c t i ca l “b r e a d a n d b u t te r ”p r ob l e m s of th e p r od u c t i on floor .A fe w of th e a r e a s i n w h i ch a m a n u fa c tu r in g e n g in e e r ca n b e e x p e c te d to w or k a r e in p l a n n i n g p r oce s s l a y ou t s , p l a n t l a y ou t , e q u i p m e n t s p e c i fica t ion , m a te r i a l s p e c i fica t ion , tool d e s ig n , m e th od s d e ve lop m e n t , w or k s ta n d a r d s , va lu e a n a l y s i s , a n d cos t con t r o l .As th e m a n u fa c tu r i n g e n g i n e e r g a in s e x p e r i e n ce , a n d i f h e h a s a h i g h d e g r e e of cr e a t iv i ty a n d in n ova t i ve a b i li t y , h e ca n e x p e c t to b e i n volve d i n th e g e n e r a t i on of m a n u fa c tu r i n g s y s t e m con ce p t s . H e w i l l a l s o b e in volve d in th e d e ve lop m e n t of n ove l a n d s p e c i a l i ze d e q u i p m e n t , r e s e a r ch i n to th e p h e n om e n a of fa b r i ca t i n g t e ch n o log i e s , a n d m a n u fa ctu r i n g fe a s i b i l i ty s tu d i e s of p r op os e d n e w p r od u c t s .N ot a l l of th e i n n ova t i on s th a t i n cr e a s e e ffi c i e n cy of m a n u fa c tu r e a r e in th e a r e a of m a ch i n e tools , i n s p e c t i on , or a u tom a te d a s s e m b l y p e r s e . In cr e a s i n ge m p h a s i s w i l l b e i n th e ch a l le n g e of th e i n d iv id u a l w or k e r . M e n on p r od u c t ion l i n e s ca n b e com e te a m s , colle c t i ve l y r e s p on s i b l e for th e e n d p r od u c t r a th e r th a n for ju s t s o m a n y r e p e t i t iou s op e r a t i on s . U n d e r th i s con ce p t , i t i s th e te a m ’s r e s p on s i b i l i ty to h e lp d e te r m i n e th e d i s t r i b u t i on of w or k , th e occu p a t i on of m a ch i n e s , a n d th e s p e e d a n d q u a l i ty of w or k . I t i s a s s u m e d th a t th e p e r s on n e l w i l l b eg ive n b r oa d e r t r a i n i n g s o th a t th e y mi g h t h a ve th e fle x i b i l i ty a n d a l l a r ou n d s k i l l to b e a b le to s te p i n w h e r e h e lp i s n e e d e d .M od e r n m a n u fa c tu r in g p l a n n i n g a l s o in c lu d e s th e u s e of th e com p u te r to h a n d le th e va s t a m ou n t of d a ta n e e d e d to u t i l i ze r a w i n for m a t i on , s u ch a s s a l e s for e ca s t s a n d cu s tom e r or d e r s , in d e te r m in i n g w h a t i s to b e p u r ch a s e d , m a d e , s tor e d , e tc ( s h ow n i n F i g u r e 5 - 1) .Th e com p u te r , i n c lu d i n g th e m in i com p u t e r a n d p r og r a m m a b le con t r o l l e r s , w i l l h a ve i n cr e a s e d im p a ct i n th e a r e a s of p r od u c t , tool, a n d p r oce s s d e s ig n for op t im u m p r od u c t i on . Com p u te r - a i d e d d e s i g n ( CAD) a n d com p u te r - a id e d m a n u fa c tu r e ( C AM ) h a ve th e p ote n t i a l of b e i n g th e l a r g e s t s i n g le d e ve lop m e n t m a n u fa c tu r in g s i n ce th e in d u s t r i a l r e volu t i on . W h e th e r th e fu l l p ote n t i a l w i l l b e r e a l i ze d i s d e p e n d e n t on i t s a cce p ta n ce b y i n d u s t r y a n d b y colle g e s a n d u n ive r s i t i e s w h e r e fu tu r e m a n u fa c tu r i n g e n g i n e e r s a r e t r a i n e d . Th i s i s n ot to im p l y th a t con s id e r a b le l e a r n in g d oe s n ot ta k e p l a ce ou t s i d e of th e for m a l c l a s s r oom . On th e con t r a r y , b e ca u s e of tod a y ’s flood of n e w s c i e n t i fi c a n d te ch n i ca l k n ow l e d g e , a n d th e a s ton i s h i n g p a ce of te ch n o log i ca l ch a n g e , th e e n g i n e e r r i s k s ob s o le s ce n ce u n le s s h e m a k e s s om e p l a n s for s e lf- s tu d y . H ow e ve r ,e ve n s h or t cou r s e s a n d colloq u i u m s m a y n ot b e s u ffi cie n t . F or m a n y a r e a s of r a p i d te ch n o log i ca l ch a n g e , a w or k cy c l e of fou r or fi ve y e a r s fo l low e d b y a y e a r on ca m p u s m a y b e a n or m a l p r a c t i ce .Purchasing control OrdersManufact-uringcontrolAssemblyworksheetsWarehousesheets CodebooksCost pricebreak-downF i g u r e 5 - 1 T h e com p u te r , w i t h i t s d a ta b a n k s a n d p r og r a m s ,i s a n e s s e n t i a l p a r t of m a n u fa c tu r i n g p l a n n i n gA u t o m a t i o n“A u tom a t i on ”is a r e l a t i ve l y n e w w or d , coin e d in 19 3 5 b y D. S . H a r d e r , th e n vice p r e s id e n t i n ch a r g e of m a n u fa ctu r i n g for th e F or d M otor C om p a n y . Th e w or d , s h or t for “a u tom a l i za t i on ”i m p l i e s d o i n g s om e th i n g a u tom a t i ca l l y or w i t h ou t h u m a n a s s i s ta n ce . Th i s m a y r e fe r to a s i n g leAutomationop e r a t i on or a n e n t i r e con t i n u ou s p r oce s s .Au tom a t i c con t r ol s y s te m s a r e n ot a p r od u ct of th i s g e n e r a t i on , J a m e s W a t t , a s e a r l y a s 178 8 , con ce ive d of a n a u tom a t i c s p e e d con t r o l for h i s s te a m e n g i n e i n th e for m of a fly - b a l l g ove r n or . Th e tw o fly b a l l s , a c t i n g b y ce n t r i fu g a l for ce , w ou ld e x te n d a s th e r p m of th e e n g i n e i n cr e a s e d . Th i s , i n tu r n , ca u s e d a m otion th a t r e d u ce d th e op e n in g a t th e in ta k e va lve . W i th l e s s s te a m i n ta k e , th e s p e e d r e d u ce d a n d th e b a l l s m ove d c los e r to th e con t r o l s h a ft , th u s r e op e n i n g th e i n ta k e va lve .An oth e r e x a m p le of e a r l y a u tom a t i on th a t i s s t i l l com m on i n m a n y s h op s i s th e fu l l y a u tom a t i c s cr e w m a ch in e . Th e i n ve n tor , Ch r i s top h e r S p e n ce r , h a d w or k e d on m a n u a l l y op e r a te d tu r r e t l a th e s . H e r e a l i ze d th a t b y a t ta ch i n g a ca m s h a ft , s t r i p ca m s , le ve r s , a n d s e g m e n t g e a r s for a c tu a t i n g th e tu r r e t , colla te , a n d cr os s s l id e , i t cou ld b e m a d e to op e r a t e a u tom a t i ca l ly . Th u s th e a u tom a t i c s cr e w m a ch i n e w a s b or n . S u r p r i s i n g ly e n ou g h , S p e n ce r d id n ot r e a l i ze th e im p or t of h i s i n ve n ti on b u t w a s con te n t to l e t th e m a ch i n e p r od u ce s cr e w s a n d oth e r s im i l a r i te m s r a th e r th a n to d e ve lop th e m a ch i n e i t s e l f.Ab ou t th e s a m e t im e a s S p e n ce r ’s a u tom a t i c s cr e w m a ch i n e w a s b u i l t i n th e U n i te d S ta te s , th e S w i s s w e r e w or k i n g ou t s im i l a r i d e a s for a n a u tom a t i c s cr e w m a ch i n e . Th e r e s e e m s to b e s om e r e lu c ta n ce to g i ve a n y on e m a n cr e d i t for th e i n ve n t i on of w h a t h a s com e to b e k n ow n a s th e S w i s s a u tom a t i c s cr e w m a ch i n e .H ow e ve r , th e con t r i b u t i on s of a b r i l l i a n t y ou n g e n g in e e r n a m e d B a ch e lor ca n n ot b e i g n or e d . H i s con ce p t of m ovin g th e m a te r i a l a x i a l l y a s i t w a s b e i n g cu t p r ovid e d a m e a n s of g e n e r a t i n g a n i n fi n i te va r i e ty of s h a p e s w i th a m in im u m of toolin g . Th e m a ch i n e , e n t i r e l y ca m - op e r a te d ,4w a s fu l ly a u tom a t ic . On e m a n cou ld look a fte r fi ve or s i x of th e s e m a ch i n e s , p r im a r i l y to s e e th a t th e y d i d n ot r u n ou t of m a t e r i a l a n d th a t th e p a r t s p r od u ce d w e r e w i th i n tole r a n ce lim i t s .N u m e r i c a l c o n t r o lA r e l a t ive l y s h or t t im e a g o m a ch i n e s w e r e op e r a te d b y cr a fts m e n w h o d e te r m in e d m a n y va r i a b le s s u ch a s s p e e d s , fe e d s , d e p th of cu t , e tc . N ow m u ch of th i s w or k i s b e i n g a s s i g n e d to com p u te r s a n d m a ch i n e s th a t a r e n u m e r i ca l ly con t r olle d . Th e w or d n u m e r i ca l i s d e fin e d a s “t h e e x p r e s s i on of s om e th in g b y n u m b e r s ”.Con t r o l i s d e fin e d a s “t h e e x e r c i s e of d i r e c t i n g , g u id in g , or r e s t r a in i n g p ow e r ove r s om e th i n g ”.B y com b i n i n g th e tw o d e fin i t i on s w e fin d th a t n u m e r i ca l con t r ol con s i s t s of d i r e ct in g , g u i d i n g , or r e s t r a i n i n g p ow e r ove r s om e th i n g b y th e u s e of n u m b e r s . S in ce n u m b e r s a r e m e r e l y s y m b ols a n d l e t te r s a r e u s e d a s w e l l, n u m e r i ca l con t r o l cou ld w e l l b e ca l l e d s y m b o l i c con t r o l .Nu m e r i ca l con t r o l h a s b e com e com m on p l a ce i n th e w or ld of m a ch i n e tools , op e n i n g u p n e w d oor s for m or e a d va n ce d con ce p t s . Tod a y , e n t i r e p r e p la n n e d a n d p r og r a m m e d d e s i g n a n d p r od u c t i on fu n c t i on s ca n b e p r oce s s e d , s tor e d , a n d fi n a l l y e xe cu te d w i t h th e a i d of a com p u te r . Th e s e fu n c t i on s a r e te r m e d CN C ( com p u te r n u m e r ica l con t r o l ) , CAD ( com p u te r - a id e d d e s ig n ) , CAM ( com p u te r - a id e d m a n u fa c tu r in g ) , a n d CIM ( com p u te r - i n te g r a te d m a n u fa c t u r in g ) .Nu m e r i ca l con t r o l ( NC ) i s con s id e r e d to b e m or e th a n a n im p r ove d con t r ol for m a ch i n e tools th a t p r ovid e s h i g h e r p r od u c t iv i ty . I t i s con s i d e r e d b y m a n y l e a d i n g s c ie n t i s t s to b e th e fi r s t s i g n i fi ca n t s te p in w h a t i s r e fe r r e d to a s th e s e con d i n d u s t r i a l r e volu t ion . Th e fi r s t i n d u s t r i a l r e volu t i on w a s u s h e r e d i n b y J a m e s W a t t’s s te a m e n g in e . H u m a n m u s c le p ow e r w a s r e p l a ce d a n d e x te n d e d5i n to a l l ty p e s of i n d u s t r i a l e q u i p m e n t . Th e s e con d r e volu t i on i s a n e x te n s i on of m a n ’s m i n d . N C, w i th th e a id of th e com p u te r , t a k e s a s y m b o l i c in p u t a n d r e s t r u c tu r e s i t to a n ou tp u t th a t e x te n d s m a n ’s con ce p t s a n d th i n k i n g i n to cr e a t ive , p r od u c t i ve r e s u l t s .Th e b i r th of NC m a y b e t r a ce d to th e l a te 19 4 0 s . At th a t t im e J oh n P a r s on s a n d h i s a s s ocia te s w e r e m a n u fa c tu r i n g h e l i cop te r b l a d e s . Th e y fou n d th e s p e ci fica t i on s , con tou r s , a n d w e i g h t s of th e a i r fo i l ve r y cr i t i c a l a n d d e m a n d i n g . S t r u g g li n g w i th th e con tou r of th e r otor b l a d e , th e y d e vis e d a n i n cr e m e n t a l l y m ovin g d im e n s i on a l i n s p e c t i on s y s te m . Th e a u th or e d d im e n s i on a l d a ta w e r efe d i n to a n e a r l y m od e l com p u te r th a t con ta i n e d th e p u r e m a th e m a t i ca lfor m u l a for th e a i r foi l . Th e i n s p e c t i on d a ta w e r e com p a r e d to th e b a s i c for m u l a . Th e id e a w or k e d s o w e l l th a t M r . P a r s on s con c lu d e d th a t i f a com p u te r cou ldte l l w h a t h a d h a p p e n e d a fte r a p a r t w a s m a d e , w h y n ot u s e th e s a m e d a ta to con t r o l a m a ch i n e tool m a d e th e p a r t . A con ce p t i s fa r fr om r e a l i t y , of cou r s e .H ow e ve r , i n 19 4 9 th e U . S . Air F or ce , w h i ch r e cog n i z e d th e va lu e of th ete ch n iq u e , a w a r d e d a d e ve lop m e n t con t r a c t to th e M a s s a ch u s e t t s In s t i tu t e of Te ch n olog y a n d b y 19 5 2 th e fi r s t n u m e r i ca l l y con t r o l l e d m a ch i n e tool w a s op e r a t i on a l .Nu m b e r s , l e t te r s , a n d s y m b o l s g a th e r e d tog e th e r a n d log i ca l l y or g a n i ze d to d i r e c t a m a ch i n e tool for a s p e c i fi c ta s k a r e ca l le d a n NC p r og r a m . Th e con ce p t i s r e volu t i on a r y in th a t th e con t r o l of a m a ch i n e h a s b e e n m ove d a w a y fr om op e r a tor s k i l l a n d in tu i t i on to a n e n t i r e l y w r i t te n p r og r a m th a t ca n b e i n te r p r e te d b y th e m a ch i n e con t r o l u n i t to p e r for m a l l th e r e q u i r e d m ove m e n t s th a t p r od u ce a fin i s h e d p a r t , n ot on l y h a s NC r e p l a ce d h u m a n s k i l l s a n d i n tu i t i on , b u t i t h a s m a d e i t p os s i b le to g e n e r a te com p le x m a ch in e m otion s6w i th a d e g r e e of p r e c i s i on th a t i s fa r b e y on d a n y h u m a n ca p a b i l i ty . If a s u r fa ce ca n b e m a th e m a t i ca l l y d e fi n e d , NC ca n con t r ol th e m a ch i n i n g of i t . B e ca u s e of th e h i g h e r p r od u c t iv i ty a ch i e ve d b y N C, i t i s b e l i e ve d th a t 75 % of a l l m e ch a n i ca l p a r t s n ot m a s s p r od u ce d cou ld b e m a d e b y NC m a ch in e tools b y th e y e a r 2 0 0 0 .C AD /C A MC om p u te r t e ch n o log y h a s r i s e n i n a n e x p on e n t i a l cu r ve . On l y a g e n e r a t i on a g o com p u te r s w e r e n ot r e a l l y n e e d e d for NC con t r o l . Ex ce p t for r e l a t i ve l y fe w fi ve - a x i s m a ch i n e s . NC w a s p o i n t to p o i n t , w h i ch w a s e a s i l y a ccom p l i s h e d w i th m a n u a l p r og r a m m in g .W i th th e a d ve n t of tw o- d im e n s i on a l p r ofi li n g , h ow e ve r , a n e e d a r os e for n u m e r ou s ca l cu l a t i on s to g e n e r a te th e cu r ve d p r ofi le . At th a t p o i n t th e com p u te r w a s look e d u p on a s a u s e fu l tool i n m a n u fa c tu r i n g e n g i n e e r i n g . Afte r s om e d e ve lop m e n t , i t w a s fou n d th a t p u n ch e d or m a g n e t i c t a p e cou ld b e d i s p e n s e d w i t h e n t i r e l y i n fa vor of com p u te r p r og r a m s th a t con t r o l l e d th em a ch i n e s d i r e c t l y . Th e n ca m e th e m i n i com p u te r s , w h i ch w h e n op e r a t i n g w i th th e ce n t r a l p r oce s s or b r ou g h t a b ou t th e fi r s t r e a l con ce p t of th e a u tom a t i c fa ctor y .All of th e s e d e ve lop m e n t s w e r e im p or ta n t s te p s i n th e a d va n ce of te ch n o log y . Th e com p u te r i s n o lon g e r vie w e d a s a r e m ote p i e ce of h a r d w a r e u s e d p r im a r i ly i n a ccou n t i n g a n d e n g i n e e r in g d e p a r tm e n t s , b u t in s te a d a s a n im p or ta n t tool to b e u s e d in cr e a s i n g l y i n CAD a n d CAM .Tod a y CAD a n d CAM h a ve b e com e c los e l y li n k e d for com p le te p r oce s s i n g fr om d e s ig n to p r od u ct i on . Th e d e s i g n e n g in e e r ca n n ow cr e a te7CAD/CAMth e d e s i r e d d e s i g n on a CR T s cr e e n th a t i s l i n k e d to a com p u te r i ze d g r a p h i cs p lotte r . Th e s a m e s y s t e m ca n b e u s e d to d e te r m i n e th e v i a b i li ty of th e d e s i g n b y a n a l y zin g s t r e s s e s a n d d e fle c t i on s th a t w i l l ta k e p l a ce u n d e r loa d i n g con d i t i on s . Th e fu n c t i on i n g of m e ch a n i ca l l i n k a g e s m a y a l s o b e ch e ck e d . Afte r th e d e s i g n i s com p le te , th e p r od u c t i on g r ou p ca n d r a w on th e i n for m a t i on d e ve lop e d on C AD for com p u te r - a id e d m a n u fa c tu r e . Th u s th e u n i fi e d CAD- CAM te a m h a s b e e n d e ve lop e d to b r i n g th e p r od u c t fr om th e d e s ig n con ce p t th r ou g h m a n u fa ctu r e .C AD F u n c t i o n sIn i t i a l l y C AD s y s te m s w e r e p r im a r i l y a u tom a t e d d r a ft i n g s t a t i on s i n w h i ch com p u te r p lotte r s p r od u ce d e n g in e e r i n g d r a w i n g s . Th e s y s te m s w e r e l a te l i n k e d to g r a p h i c d i s p l a y t e r m i n a l s , w h i ch a l low e d th e u s e r to com m u n i ca te w i th th e com p u te r i n p i ctu r e s i n s te a d of r a w colu m n s of n u m b e r s . N ow a d va n ce d s y s t e m s h a ve a d d e d a n a l y t i ca l ca p a b i l i t i e s . CAD fu n ct i on s m a y b e g r ou p e d i n to fou r m a j or ca te g or i e s : g e om e t r i c m od e l i n g , e n g i n e e r i n g a n a l y s i s , k i n e m a t i c s , a n d a u tom a te d d r a ft i n g .C A M F u n c t i o n sCAM fu n c t i on s ce n te r a r ou n d fou r m a i n a r e a s : n u m e r i ca l con t r ol, p r oce s s p l a n n i n g , r ob otics , a n d fa ctor y m a n a g e m e n t .8制造业中的新技术制造业面临的挑战对资深的制造工程师的要求从来没有像现在这样如此受到关注。
机械专业文献带翻译
机械专业文献带翻译Title: Research and Development of a Novel Mechanical Device for Automated Assembly of Small Parts。
Abstract:The assembly of small parts is a time-consuming and labor-intensive process, often requiring skilled workers to perform the task. In order to improve efficiency and reduce costs, a novel mechanical device for automated assembly of small parts has been developed. This device is capable of handling a variety of small parts with high precision and speed, and can significantly reduce the time and cost required for assembly.Introduction:The assembly of small parts is a critical process in many industries, including electronics, automotive, and medical device manufacturing. This process often requiresskilled workers to perform the task, which can be time-consuming and costly. In addition, human error can lead to defects and quality issues, further increasing costs and reducing efficiency.To address these challenges, a novel mechanical device for automated assembly of small parts has been developed. This device is capable of handling a variety of small parts with high precision and speed, and can significantly reduce the time and cost required for assembly.Design and Development:The mechanical device for automated assembly of small parts consists of several key components, including a feeder, a manipulator, and a control system. The feeder is responsible for delivering small parts to the manipulator, which then assembles the parts according to a predetermined pattern. The control system coordinates the movements of the feeder and manipulator, ensuring that the assembly process is carried out with high precision and speed.The design of the manipulator is particularly important, as it must be capable of handling a wide range of smallparts with varying shapes and sizes. The manipulatorconsists of a series of grippers and suction cups, whichcan be adjusted to accommodate different types of parts.The grippers and suction cups are controlled by a series of motors and sensors, which ensure that the parts are picked up and assembled accurately.Testing and Evaluation:The mechanical device for automated assembly of small parts has been tested extensively in a laboratory setting, and has demonstrated high levels of precision and speed.The device is capable of handling a wide range of small parts, including electronic components, screws, and bolts.In addition, the device has been shown to significantly reduce the time and cost required for assembly, compared to manual assembly methods.Future Directions:The mechanical device for automated assembly of small parts has significant potential for use in a variety of industries, including electronics, automotive, and medical device manufacturing. Further research and development is needed to optimize the design and performance of the device, and to explore its potential for use in new applications.Conclusion:The development of a novel mechanical device for automated assembly of small parts has the potential to revolutionize the assembly process in many industries. This device is capable of handling a wide range of small parts with high precision and speed, and can significantly reduce the time and cost required for assembly. Further research and development is needed to optimize the design and performance of the device, and to explore its potential for use in new applications.。
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外文原文：The new advanced manufacturing technology developmentAbstract : This paper has presented the problems facing today's manufacturing technology, advanced manufacturing discussed in the forefront of science, and a vision for the future development of advanced manufacturing technology.Keyword：Advanced manufacturing technologies; Frontier science; Applications prospectsModern manufacturing is an important pillar of the national economy and overall national strength and its GDP accounted for a general national GDP 20%~55%. In the composition of a country's business productivity, manufacturing technology around 60% of the general role. Experts believe that the various countries in the world economic competition, mainly manufacturing technology competition. Their competitiveness in the production of the final product market share. With the rapid economic and technological development and customer needs and the changing market environment, this competition is becoming increasingly fierce, and that Governments attach great importance to the advanced manufacturing technology research.1 .Current manufacturing science to solve problemsManufacturing science to solve the current problems focused on the following aspects :(1) Manufacturing systems is a complex systems, and manufacturing systems to meet both agility, rapid response and rapid reorganization of the capacity to learn from the information science, life science and social science interdisciplinary research, and explore new manufacturing system architecture, manufacturing models and manufacturing systems effective operational mechanism. Manufacturing systems optimized organizational structure and good performance is manufacturing system modelling, simulation and optimization of the main objectives. Manufacturing system architecture not only to create new enterprises both agility and responsiveness to theneeds and the ability to reorganize significance, but also for the soft production equipment manufacturing enterprises bottom reorganization and dynamic capacity to set higher demands. Biological manufacturing outlook increasingly being introduced to the system to meet new demands manufacturing systems.(2) The rapid rise in support of manufacturing, geometric knowledge sharing has become a modern manufacturing constraints, product development and manufacturing technologies of the key issues. For example, in computer-aided design and manufacturing (CAD/CAM) integration, coordinates measurements (CMM) and robotics fields, in 3D real space (3-Real Space), there are a lot of geometric algorithm design and analysis, especially the geometric said, geometric calculation and geometric reasoning; In measurement and robot path planning and parts search spaces (such as Localization), the existence of space C- interspace (configuration space Configuration Space) geometric calculation and geometric reasoning; Objects in operation (rescue, paying and assembly, etc.) means paying more description and robot planning, campaign planning and assembly operations planning is needed in the types of space (Screw Space) geometric reasoning. Manufacturing process of physical and geometric mechanics phenomenon of scientific research to create a geometric calculation and geometric reasoning, and other aspects of the research topic, the theory pending further breakthrough, the new one door disciplines -- computer geometric are being increasingly broad and in-depth study.(3) In the modern manufacturing process, information not only manufacturing industries have become dominated the decisive factor, but also the most active ones. Manufacturing information systems to improve throughput of modern manufacturing has become a focus of scientific development. The manufacturing information system organization and structure required to create information access, integration and integration show three-dimensional in nature, measuring the multidimensional nature of the information, and information organizations nature. Information structure models in the manufacturing, manufacturing information consistency constraint, and the dissemination of data processing and the manufacture of enormous knowledge base management, and other areas, there is a need to further breakthroughs.(4) The calculation of the wisdom of artificial intelligence tools and methods in the manufacture of a wide range of applications for manufacturing smart development. Category based on the calculation of biological evolution algorithms smart tools, including activation issues optimize GPS technology portfolio by growing concern is in the manufacture of the complete portfolio optimization problems combined speed and precision of GPS issues both in size constraints. Manufacturing wisdom manifested in the following aspects : wisdom activation, wisdom design, intelligent processing, robotics, intelligent control, intelligent process planning, smart diagnostic, and other aspects. These innovative products are the key theoretical issues, but also by creating a door for a science skills in the important basic issues. The focus in these issues, we can form the basis of product innovation research system.2. Modern mechanical engineering at the frontiers of scienceCross-integration between the different science will produce new scientific gathering, economic development and social progress of science and technology created new demands and expectations, thus creating a frontier science. Frontier science is settled and unsettled issues between the scientific community. Frontier science, with a clear domain, and dynamic character of the area. Works frontier science from the general basic science is an important characteristic of the actual works, it covers the key emerging science and technology issues. Ultrasonic electrical, ultra-high-speed machines, green design and manufacturing, and other fields, and has done a lot of research work, but innovation is the key question is not clear mechanical science. Large complex mechanical system design and performance optimization of product innovation design, smart structures and systems, intelligent robots and their dynamics, nano Mocaxue, manufacturing process 3D numerical simulations and physical simulation, precision and ultra-fine processing technology key basis, about 10 mega large and sophisticated equipment design and manufacturing base, virtual manufacturing and virtual instruments, nanometer measurement and instrumentation, parallel connection axis machine tools, and although the field of micro-electromechanical systems have done a lot of research, but there are still many key science and technology issues to be resolved. Information science, nanoscience, materials science, life science, management science and manufacturing science of the 21st century will be to change the mainstream science, and the resulting high-tech industry will change the face of the world. Therefore, the above areas of cross-development manufacturing systems and manufacturing informatics, nano manufacturing machinery and nano science, better machinery and better manufacturing science, management science and manufacturing systems will be critical to the 21st century mechanical engineering science is important frontier science.2.1 Manufacturing science and information science cross -- manufacturing informaticsMechanical and electrical products, chemical raw materials in the information. Many modern value added products primarily reflected in the information. Thus the manufacturing process for the acquisition and application of information is very important. Information science and technology is to create an important symbol of globalization and modernization. While the manufacturing technology began to explore product design and manufacturing processes, the nature of the information, on the other hand, to create technology to transform itself to adapt to the new information makes its manufacturing environment. Along with the manufacturing process and manufacturing systems to deepen understanding, researchers are trying to new concepts and approaches to their description and expression to achieve further control and optimization purposes.And manufacturing-related information mainly product information, technical information and information management in this area following major research direction and content :(1) manufacturing information acquisition, processing, storage, transmission and application of knowledge to create information and decision-making transformation.(2) Non-symbols expressing information, manufacturing information enables transmission, manufacturing information management, manufacturing information integrity in a state of non-production decision-making, management of virtual manufacturing, based on the network environment of the design and manufacturing,manufacturing process control and manufacturing systems science. These elements are manufactured in science and the scientific basis for the integration of product information, constitute the manufacture of the new branch of science -- to create informatics.2.2 Micro mechanical and manufacturing technology researchMicro-electronic mechanical systems (MEMS) refers to the collection of micro-sensors, micro-devices and the implementation of signal processing and control circuits, interface circuits, communications and power with the integration of micro-electromechanical system integrity. MEMS technology objectives through system miniaturization, to explore a new theory of integration, new functional components and systems. MEMS development will greatly facilitate the pocket of various products, miniaturization, a number of devices and systems to enhance the level of functional density, information density and Internet density, significantly saving, thin section. Not only can it reduce the cost of mechanical and electrical systems, but also to be completed and the size of many large systems impossible task. For example, using sophisticated 5μm diameter micro tweezers walls are made of a red blood cell can; Created to keep the cars 3mm size; In the magnetic field, like butterflies flying size aircraft. MEMS technology has opened up a completely new technology areas and industries, with many traditional sensors incomparable advantages in manufacturing, aerospace, transportation, telecommunications, agriculture, biomedical, environmental monitoring, military, families, and access to almost all areas have very broad application prospects.Micro machinery is machinery and electronic technology in nano-scale technology integration photogenic product. Back in 1959 scientists have raised the idea of micro-mechanical and micro-1962, the first silicon pressure sensors. 1987 California University of California Berkeley developed rotor diameter of the silicon micro-60~120 16ug m electrostatic electric motors, show produced using silicon micro-machining small movable structures and compatible with IC manufacturing micro system potential. Micro-mechanical technology might like 20th century microelectronics technology, the technology of the world in the 21st century,economic development and national defense building a tremendous impact. Over the past 10 years, the development of micro-mechanical spectacular. Its characteristics are as follows : a considerable number of micro-components (micro structure, the implementation of micro-sensors and micro-machines, etc.) and micro-systems research success reflects the current and potential applications of value; The development of micro-manufacturing technology, particularly semiconductor processing technology have become small micro systems support technology; micro-electromechanical systems research needs of the interdisciplinary research team, micro-electromechanical systems technology in the development of microelectronics technology on the basis of multidisciplinary cross-frontier area of research, involving electronic engineering, mechanical engineering, materials engineering, physics, chemistry and biomedical engineering and other technical and scientific.The current micro-mechanical systems under the conditions of the campaign laws, the physical characteristics and micro components of the role of the mechanics payload acts lack adequate understanding is not yet in a theoretical basis for a micro-system design theory and methodology, and therefore can By experience and test methods research. Micro-mechanical systems, the existence of key scientific research issues of micro-scale system effects, physical properties and biochemical characteristics. Micro-system research are in the eve of a breakthrough, which is the in-depth study of the area.2.3 Material produced / manufactured parts integration of new technologies for processing.Material is a milestone in the progress of mankind, is the manufacturing and high-tech development. Every important to the success of the production and application of new materials, will promote the material and the promotion of national economic strength and military strength. 21, the world will be resource consumption-based economy to a knowledge-based industrial transformation for materials and parts and functions of a high performance, intelligent features; Request materials and components designed to achieve quantitative-based and digitized; Prepare materials and components for the rapid, efficient and achieve both integrationand integrated. Digital materials and components designed to be a simulation and optimization of materials and components to achieve high quality production / manufacturing and other integration, integrated manufacturing key. On the one hand, to be completed through computer simulation optimization can reduce the material is produced in the course of manufacture of spare parts and experimental links to the best craft programmes, materials and components to achieve high quality production / manufacturing; On the other hand, according to the requirements of different material properties, such as flexible modules volume, thermal expansion coefficient, magnetic performance, Research materials and components designed form. And the removal of traditional materials-manufacturing technology, and increase the level of information technology, the research group of synthetic materials is a process technology. Forming materials and components manufacture digital theory, technology and methods, such as rapid adoption of emerging technologies material growing principles, a breakthrough in the traditional law and to build law mechanical deformation processing many restrictions, no processing tools or dies, can rapidly create arbitrary complex shape and has a certain function 3D models or entity parts.2.4 machinery manufacturing breakthroughThe 21st century will be the century of life science, mechanical and life sciences depth integration will generate new concept products (such as better intelligence structure), to develop a new process (such as the growth processes shape) and the opening of new industries and to resolve product design, manufacturing processes and systems provide a series of problems new solutions. This is a highly innovative and leading edge area in the challenge.Earth's biological evolution in the long accumulated fine qualities of human manufacturing activities to address the various problems with examples and guidelines. Learning from life phenomena organizations operating complex systems and methods and techniques, manufacturing is the future solution to the current problems facing many an efficient way. Better manufacturing refers to the replication of biological organs from organizations, since healing, self growth and evolution since the function of the model structure and operation of a manufacturing system andmanufacturing process. If the manufacturing process mechanization, automation extends human physical and intelligent extension of the human intellectual, then "create better" may be said to extend its own organizational structure and human evolution process.Gene involved in the manufacture of biological science is the "self-organization" mechanism and its application in manufacturing systems. The so-called "self-organization" refers to a system in its internal mechanism driven by the organizational structure and operation mode learning, thereby enhancing the capacity for environmental adaptation process. Create better "since the organization" bottom-up mechanism for parallel product design and manufacturing processes of automatic generation, the dynamics of production systems and manufacturing systems and products more automatic a theoretical foundation and achieve superior conditions.Create a better manufacturing and life sciences "far edge hybrid" of the 21st century manufacturing will have an enormous impact. Create better research content is twofold :2.4.1 To create better livesResearch lives of the general phenomenon of the law and models, such as artificial life, cellular automatic machines, biological information processing skills, biological wisdom, biological-based organizational structure and mode of operation and the evolution of biological mechanisms and getting better;2.4.2 Oriented manufacturing breakthrough manufacturingResearch organizations better manufacturing systems since the mechanisms and methods, for example : based on full information-sharing breakthrough design principles, multi-discipline modules based on the distributed control and coordination mechanism based on the evolution of an excellent strategy; Study the concept of creating better system and its basis, such as : the formalization described space and better information shine upon relations better system and its evolution of complexity measurement methods.Machinery manufacturing is better and better mechanical science and life science, information science, materials science disciplines such as high integration, the studyincludes growth formative processes, better design and manufacturing systems, mechanical and biological wisdom better shape manufacturing. Currently doing research mostly forward exploratory work, with distinct characteristics of the basic research, if the research continues to seize opportunities that might arise revolutionary breakthroughs. Future research should concern areas of biological processing technology, better manufacturing system, based on rapid prototype manufacturing engineering technology organizations, as well as biological engineering related key technical basis.3. Modern manufacturing technology trendsSince the beginning of the 1990s, the nations of the world have manufacturing technology research and development as a national priority for the development of key technologies, such as the United States advanced manufacturing technology plan AMTP, Japan wisdom manufacturing technology (IMS) international cooperation schemes, Korea senior national plan of modern technology (G--7), Germany plans to manufacture 2000 and the EC Esprit and BRITE-EURAM plan.With the electronics, information, the constant development of new and high technologies, market demand individuality and diversity, the future of modern manufacturing technology to the overall development trends of the sophisticated, flexible, and networked, virtual and intelligent, green integrated, globalization direction.Current trends in modern manufacturing technology has the following nine areas :(1) Information technology, management techniques and technology closelyintegrated technology, modern production model will be continuous development.(2) Design techniques and more modern means.(3) Shaped and manufacture of sophisticated technology and manufacturingprocesses to achieve longer.(4) The formation of new special processing methods.(5) Development of a new generation of ultra-sophisticated, ultra-high-speedmanufacturing equipment.(6) Machining skills development for the engineering sciences.(7) Implementation of clean green manufacturing.(8)The widespread application of virtual reality technology to the manufacturingsector.(9) To create people-oriented.译文：先进制造技术的新发展摘要：本文介绍了当今制造技术面临的问题，论述了先进制造的前沿科学，并展望了先进制造技术的发展前景。