【机械类文献翻译】关于数控车床
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）。
【机械类文献翻译】车床2
外文翻译车床车床主要是为了进行车外圆、车端面和镗孔等项工作而设计的机床。
车削很少在其他种类的机床上进行，而且任何一种其他机床都不能像车床那样方便地进行车削加工。
由于车床还可以用来钻孔和铰孔，车床的多功能性可以使工件在一次安装中完成几种加工。
因此，在生产中使用的各种车床比任何其他种类的机床都多。
车床的基本部件有：床身、主轴箱组件、尾座组件、溜板组件、丝杠和光杠。
床身是车床的基础件。
它能常是由经过充分正火或时效处理的灰铸铁或者球墨铁制成。
它是一个坚固的刚性框架，所有其他基本部件都安装在床身上。
通常在床身上有内外两组平行的导轨。
有些制造厂对全部四条导轨都采用导轨尖朝上的三角形导轨（即山形导轨），而有的制造厂则在一组中或者两组中都采用一个三角形导轨和一个矩形导轨。
导轨要经过精密加工以保证其直线度精度。
为了抵抗磨损和擦伤，大多数现代机床的导轨是经过表面淬硬的，但是在操作时还应该小心，以避免损伤导轨。
导轨上的任何误差，常常意味着整个机床的精度遭到破坏。
主轴箱安装在内侧导轨的固定位置上，一般在床身的左端。
它提供动力，并可使工件在各种速度下回转。
它基本上由一个安装在精密轴承中的空心主轴和一系列变速齿轮(类似于卡车变速箱)所组成。
通过变速齿轮，主轴可以在许多种转速下旋转。
大多数车床有8~12种转速，一般按等比级数排列。
而且在现代机床上只需扳动2~4个手柄，就能得到全部转速。
一种正在不断增长的趋势是通过电气的或者机械的装置进行无级变速。
由于机床的精度在很大程度上取决于主轴，因此，主轴的结构尺寸较大，通常安装在预紧后的重型圆锥滚子轴承或球轴承中。
主轴中有一个贯穿全长的通孔，长棒料可以通过该孔送料。
主轴孔的大小是车床的一个重要尺寸，因此当工件必须通过主轴孔供料时，它确定了能够加工的棒料毛坯的最大尺寸。
尾座组件主要由三部分组成。
底板与床身的内侧导轨配合，并可以在导轨上作纵向移动。
底板上有一个可以使整个尾座组件夹紧在任意位置上的装置。
数控车床外文翻译3
本科生毕业设计 (论文)
外文翻译
原文标题数控车床
译文标题Numerical Control Lathes
作者所在系机械工程系
作者所在专机械设计制造及其自动化作者所在班
作者姓名
作者学号
指导教师姓
指导教师职
完成时间2012 年 2 月28
注：1. 指导教师对译文进行评阅时应注意以下几个方面：①翻译的外文文献与毕业设计（论文）的主题是否高度相关，并作为外文参考文献列入毕业设计（论文）的参考文献；②翻译的外文文献字数是否达到规定数量（3 000字以上）；③译文语言是否准确、通顺、具有参考价值。
2. 外文原文应以附件的方式置于译文之后。
机械类数控车床外文翻译外文文献英文文献数控
机械类数控车床外文翻译外文文献英文文献数控原文来源：Zhao Chang-ming Liu Wang-ju (CNC Machining Process and 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进展趋势及计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，数控技术及装备是进展新兴高新技术产业和尖端工业〔如信息技术及其产业、生物技术及其产业、航空、航天等国防工业产业〕的使能技术和最差不多的装备。
外文翻译--数控车床
CNCWhat is CNC?Computer numerical control is a very broad term that encompasses a variety of types of machines—all with different sizes, shapes, and functions. But the easiest way to think about CNC is to simplyunderstand that it’s all about using a comp uter as a means to control a machine that carves usefulobjects from solid blocks of material. For example, a CNC machine might begin with a solid block ofaluminum, and then carve away just the right material to leave you with a bicycle brake handle.CNC machines can be divided into two groups: turning machines and milling machines. A turningmachine is generally made up of a device that spins a workpiece at high speed and a tool (sharp edge)that shaves off the undesired material from the workpiece (where the tool is moved back and forth andin and out until the desired form is achieved). A milling machine is a machine that has a spindle (adevice similar to a router) with a special tool that spins and cuts in various directions and moves in threedifferent directions along the x, y, and z axes.Historically, you wouldn’t actually need a computer to create forms with a turning machine or amilling machine. Adding a computer to the mix allows you to design a product on a computer first andthen specify how the machine should cut this product. To design the product is to produce acomputeraideddesign (CAD) file. Then you specify how the machine should cut the product, and the result of thatstep is a computer-aided manufacturing (CAM) file (or G-Code file, or .NC file—there are many namesfor this type of file). This CAM file remembers all of the operations that the milling machine must followto cut out the parts for the product. The computer tells the CNC machine how to build the part byinterpreting the CAM file into signals that the CNC machine can understand.Industrial UsesIndustrial applications for CNC machines have been chiefly based around the removal of metal to create adesired form. Metal is widely used for producing almost everything we see around us, even though these things may not be made of metal themselves. Some of the most obvious products that are made ofmetal are cars. The engine block and the parts within the transmission are directly produced from a CNCmachine because tight tolerances are necessary (a tolerance is a range in dimensioning to which themachine must adhere). However, most of the parts of a car are not made by a CNC machine, but theyhave a latent connection to one. For example, how do you make a quarter panel? There is a hydraulicpress with a thing called a die to create an impression in a sheet of metal. Most of the parts of thehydraulic press were made from a CNC machine. The die, the part that carries the negative form of thequarter panel and that can be replaced when design changes, was also made by a CNC machine, andthen tempered for hardening and heat resistance. Even the plastic parts of a car have some connectionto a CNC machine. Many of these parts were made from a mold that was created using a CNC machineBecause CNC machines have very high precision and they can provideinformation back to thecomputer, they are also used in dimensional testing. If a switch (probe) is fastened to the location of thetool, it can analyze the measurements of a part that was produced. The machine runs this probe all overthe part to confirm its desired form and measurements.For more information on industrial uses of CNC machines, visitPersonal UsesThere is a large following by various hobbyists and DIYers around the globe interested in the concept ofCNC machines. Roboticists, craftsmen, handymen, home machinists, small business owners, techenthusiasts, backyard scientists, and artists have all discovered how a CNC machine can open doors tonew designs and more detailed creations. A roboticist, for instance, will use a CNC machine to create thestructural components of the robot with very high precision. Making these components by hand wouldbe tedious and very time consuming. Using a CNC machine, the parts come out beautifully and fittogether with great precision.For the typical handyman, a great example of using a CNC machine might be designing and making cabinets for around the house. Typically, cabinets share many of the same dimensions and can be cut bya CNC machine over and over. Imagine cutting all of the drawers and cabinet lids by hand! The parts arenumerous and the work would be quite tedious. But with a CNC machine, the individual pieces are cutand the cabinets assembled; no driving around looking for the right cabinets, having to special orderthem, and then waiting for delivery from the home improvement store. (The cabinets will needassembly, too, but with your own CNC machine, you’ll find that the high cost of buying them in t he storecan be eliminated.) CNC machines for personal use can be purchased from a variety of manufacturers, but many DIYers suffer from sticker shock the first time they begin shopping for a CNC machine. Prices of $3,000 andhigher are typical for small,de sktop versions that often come with a 12"×18" workspace, meaning you’llbe limited to working on materials that fit in that small space. CNC machines with workspaces that allowfor materials of 2'×4', for example, start around $7,000, and prices go much higher for larger workspacetables.For most DIYers, owning their own CNC machine is still out of reach financially. But no longer—thisbook brings CNC within easy reach. If you can afford to spend $700 to $800, then you can afford to buildyour very own CNC machine.Your DIY CNC MachineWith your DIY CNC machine, you’re going to be able to do some amazing things—cut, drill, etch, and sculpt—with a variety of materials. In fact, author Patrick Hood-Daniel uses his own CNC machines to make more CNC machines! He has a machine cut and drill the MDF (medium-density fiberboard) parts used to build more CNC machines. (You can do this, too, but first you’ll need to build your own DIY CNC machine—it all starts there.)Your DIY CNC machine is made of MDF, a rigid material that holds up well to cutting and drilling, as well as being extremely strong and dimensionally stable (itdoesn’t shrink or expand with fluctuations in the weather or humidity). The MDF parts you’ll be cutting and drilling are bolted together using a varie ty of sizes of bolts, nuts, washers, and other hardware. Finally，you’ll be adding a mix of electronics and one computer to bring your DIY CNC machine to life and amaze your friends and family (who will,unfortunately, come up with all kinds of requests for you and your machine).The DIY CNC machine isn’t something with vague dimensions and a random mixture of hardware.We’ll tell you exactly what to buy. You’ll be cutting and drilling material from plans created by authorPatrick Hood-Daniel and tested and used to build three machines; one by James Floyd Kelly, one by Darrell Kelly, and one by Jim Burt (not to mention the number of machines built by Patrick himself).When you’re done, however, you’re not really done. CNC is a growing and changing technology, so the limits of what you can do with your machine are really up to you. While this book will give you the basic information to build and use your machine, you’ll want to continue to improve your skills by delving deeper into the software and pushing the limits of your machine. (We’ll provide you with some good resources for further research and learning later in the book.)If you’re like us, you’re ready to begin. But trust us when we say that one of the best things you cando before starting to build your own CNC machine is this: read the entire book through at least once.Doing so will give you a glimpse of the final machine and a better understanding of how you’ll get there.You may find, as we did, that half the fun of owning your own DIY CNC machine comes from building it. HISTORY OF THE DIY CNC MACHINE, FROM PATRICK HOOD-DANIEL My desire to hop on the bandwagon of this great hobby started as a means to an end. The end has not beenrealized because I became more interested in the CNC machine itself and want to provide simpler designs and ，instruction to others who wouldn’t otherwise have the means to own a traditional CNC machine.The DIY CNC community has been around for a long time; pretty much ever since the boom of the Internet. I learned most of what I know from the information on the Internet. With my prior design training, I spent quite a bit of time improving what others had created.Through my effort to create an initial CNC machine from resources on the Internet, I found that the materialsdid not hold up well with use and tended to exhibit undesirable flexing. I learned through trying and experimenting. . . and discovered many things that worked and didn’t work. I quickly learned, for example, to stick with MDF asthe material of choice for making my CNC machines.Over the years, I made hundreds of trips to the home improvement store (my laboratory of ideas). The components that I used to start my CNC journey included round metal bar stock and a bunch of very cheap MDF.I thought that the metal stock would have some pretty good rigidity—I mean . . . it’s metal! But I was very wrong.After putting an assembly together and using the bar stock as the rail, I noticed quite a bit of flexing in the assembly. This was not going to work, so I came up with abetter way. (I was deathly afraid of trying something ，that was not illustrated on the Internet in fear that if it wasn’t done before, it wouldn’t work. But I did it anyway.) I used aluminum angles as the rails and MDF as the midsection between the rails to provide the necessary rigidity.Initially, I tried the bar stock with this technique, but the bars would still flex. The aluminum rails wrapping the MDF worked perfectly and the machine was rigid and stable—perfect! Well, perfect is a subjective word here, but it was good enough for me. And I think by the time you’re done following this book’s instructions and building your own machine, you’ll agree.Everything from that point on became intuitive. The mechanics and motion of the machine were all designedso that the parts could be cut, drilled, and assembled using nothing more than a few simple hand tools. (I’m notkidding—the early machines were cut and drilled with nothing more than a mitre box, a small saw, and a batterypowered drill.)This book documents my design; you’ll be able to skip th e frustration that I faced because this is the design Ideveloped that worked. The DIY CNC machine fulfills my desire to provide others with a simple, elegant, and fullyfunctional CNC machine. The ToolsWe cannot predict what tools you’ll have available dur ing the building of your machine. We can, however,tell you the tools we used. Some of these tools, especially the power tools, can easily be rented (by the dayor hour) at hardware stores and home centers, while others may be slightly difficult to find. And if you have ，access to a tool or two not mentioned here, that could make your work even easier. Just keep in mind,however, that this machine was designed so that it could be built with a minimum number of tools—if you find yourself lacking a tool described followinga nd cannot find it (for purchase or rent), don’t let that stop you; just improvise with the tools you do have. The CNC machine built in this book is extremely forgiving when it comes to small deviations in cutting and drilling; be as accurate as you can, use what you have available, and make the best of it.Following is a list of our tools, with a few photos for clarification:• Table saw: This is useful for cutting long lengths of MDF accurately. Depending on your skill, youcan also cut multiple MDF pieces at once, guaranteeing they match in dimensions.• Metal band saw: This is used for cutting the aluminum angled rail and lead screws • Hack saw: If a band saw is not available, this is the saw to use for cutting the aluminum angled rail and lead screws.• Mitre box: This is useful for making accurate cuts in small MDF pieces.• Hammer: This is for hammering things, obviously• Cordless screwdrivers: You’ll need a Phillips and a slot head.• Regular screwdrivers: Again, you’ll need a Phillips and a slot head.• Forstner drill bits: Forstner bits (see Figure 2-1) are extremely useful for counterboring as well as drilling large, smooth holes; regular drill bits can be used to drill counterbored holes, but thesework much betterFigure 2-1. Forstner drill bits in various sizes• Brad point drill bits: These drill a flat-bottomed hole and have a sharp, centered tip that creates a“dimple” that can be used to center other drill bits for later drilling.• Twisted drill bits: These are your standard drill bits and co me in a range of sizes. • Spade drill bits: This is another common variety of drill bit that is perfectly acceptable for drilling holes.• Transfer punches: Transfer punches (see Figure 2-2) are available in different diameters. These tools have a sharp point on the end; inserting them into existing drilled holes will allow you to make a “dimple” in a second piece of MDF, giving youan accurate point to drill on the secondpiece of MDF.Figure 2-2. Transfer punches let you mark other pieces accurately for drilling. • Magnetic bowl: This is a small bowl that can keep your nuts and bolts from falling all over the floor.• 1/2" power drill: Having a drill that can handle larger-diameter drill bits will be very useful during the build.• Drill press: Useful for drilling straight holes (vertically) through material. A drill press also provides a small table to clamp MDF and aluminum rail to when drilling. • Wrenches: You’ll need wrenches for 1/4" nuts.• Detail metal ruler: This is a special type of ruler (see Fi gure 2-3) with marks that allow you to make extremely straight lines for cutting and points for drilling. Measuring and marking increments of 1/8", 1/16", 1/32", and 1/64" are possible withthese rulers.Figure 2-3. These rulers are from Incra and are extremely accurate.数控车床一、什么是计算机数控计算机数控是一种非常广泛的专业术语，它包含各种类型的机器，比如各种大小，形状和功能的机器。
数控车床外文翻译3
本科生毕业设计 (论文)
外文翻译
原文标题数控车床
译文标题Numerical Control Lathes
作者所在系机械工程系
作者所在专机械设计制造及其自动化作者所在班
作者姓名
作者学号
指导教师姓
指导教师职
完成时间2012 年 2 月28
注：1. 指导教师对译文进行评阅时应注意以下几个方面：①翻译的外文文献与毕业设计（论文）的主题是否高度相关，并作为外文参考文献列入毕业设计（论文）的参考文献；②翻译的外文文献字数是否达到规定数量（3 000字以上）；③译文语言是否准确、通顺、具有参考价值。
2. 外文原文应以附件的方式置于译文之后。
数控车床主轴部件机械外文文献翻译、中英文翻译、外文翻译
数控车床主轴部件机械外文文献翻译、中英文翻译、外文翻译数控车床主轴部件车床是一种主要用于加工旋转表面和平整边缘的机床。
根据使用目的、结构、刀具数量和自动化程度的不同，车床可以分为普通车床、万能车床、转塔车床、立式车床、自动车床和特殊车床。
虽然车床种类繁多，但它们在结构和操作原理上具有共同特性。
普通车床是最常用的代表类型，下面将介绍普通车床的主要部分。
车床床身是车床的主骨架，由两个垂直支柱上的水平横梁组成。
为减振，它通常由灰铸铁或球墨铸铁铸造而成。
车床床身上有导轨，可以让大拖板轻松纵向滑动。
车床床身的高度应适当以方便技师工作。
主轴箱固定在车床床身的左侧，包括轴线平行于导轨的主轴。
主轴通过齿轮箱驱动，齿轮箱可以提供多种不同的速度(通常是6到18速)。
现代车床有些采用无级调速主轴箱，采用摩擦、电力或液压驱动。
主轴往往是中空的，纵向有一通孔，可以通过此孔进给棒料。
同时，此孔为锥形表面，可以安装普通车床顶尖。
主轴外表面是螺纹，可以安装卡盘、花盘或类似的装置。
尾架总成包括底座、尾架体和套筒轴。
底座是能在车床床身上沿导轨滑动的铸件，有定位装置，可以让整个尾架根据工件长度锁定在任何需要位置。
使用手轮和螺杆，与螺杆啮合的是一固接在套筒轴上的螺母。
套筒轴开口端的孔是锥形的，能安装车床顶尖或诸如麻花钻和镗杆之类的工具。
套筒轴通过定位装置能沿着它的移动路径被锁定在任何点。
大拖板的主要功能是安装刀具和产生纵向和/或横向进给。
它实际上是一由车床床身V形导轨引导的、能在车床床身主轴箱和尾架之间滑动的H形滑块。
大拖板可以手动或通过溜板箱和光杆(进给杆)或丝杆(引导螺杆)机动。
本文介绍了在传统普通车床上进行的各种机加工作业。
但是，需要注意的是现代计算机数控车床具有更多的功能，并且可以进行其他操作，例如仿型。
圆柱面车削是所有车床操作中最简单也是最常见的。
工件旋转一整圈产生一个圆心落在车床主轴上的圆；由于刀具的轴向进给运动，这种动作重复许多次。
机床工具——机械类外文文献翻译、中英文翻译
机床工具——机械类外文文献翻译、中英文翻译本文旨在对机床工具的相关外文文献进行翻译，并提供中英文对照。
以下是翻译内容：1. 文献标题：Machine Tools in the Manufacturing Industry机床工具在制造业中的应用2. 文献摘要：摘要内容省略3. 引言：引言内容省略4. 机床工具的定义和分类4.1 定义机床工具是指用于加工金属、塑料等材料的机械设备。
它们可以通过切削、打孔、钻孔等方式来改变工件的形状和尺寸。
机床工具在制造业中扮演着重要的角色，是生产加工的关键设备之一。
4.2 分类机床工具根据加工方式和功能可以分为多种类型，包括但不限于：- 钻床：用于钻孔和打孔的机床工具。
- 铣床：用于平面和曲面的加工，常用于零件的修整和切割。
- 车床：用于旋转对称零件的加工，可进行螺纹加工。
- 磨床：用于零件的磨削，获得更高的平滑度和精度。
- 刨床：用于平面的加工，可进行切削和修整。
- 冲床：用于冲压工艺，可用于冲孔和冲剪。
5. 机床工具的应用和发展趋势5.1 应用机床工具广泛应用于制造业的各个领域，包括汽车制造、航空航天、电子设备、家电等。
它们在产品加工、零部件制造和整体生产中起着关键作用。
5.2 发展趋势随着科技的不断进步，机床工具也在不断发展和创新。
以下是一些机床工具的发展趋势：- 数控机床：采用数字控制技术，提高加工效率和精度。
- 智能机床：结合人工智能和自动化技术，实现智能化生产和优化生产流程。
- 柔性机床：具有多功能和快速转换能力，适应不同产品和加工需求。
- 环保机床：注重节能和环境友好，减少废料和排放。
- 精密机床：追求更高的精度和平滑度，满足特殊加工要求。
6. 结论：结论内容省略以上是对机床工具的相关外文文献进行的翻译，提供了中英文对照。
机床工具在制造业中具有重要作用，并且随着科技的发展，机床工具的应用和发展也呈现出新的趋势和特点。
(数控加工)机械类数控外文翻译外文文献英文文献数控精编
（数控加工）机械类数控外文翻译外文文献英文文献数控NumericalControlOneofthemostfundamentalconceptsintheareaofadvancedmanufactur ingtechnologiesisnumericalcontrol(NC).PriortotheadventofNC,allmachine toolsweremanualoperatedandcontrolled.Amongthemanylimitationsassoc iatedwithmanualcontrolmachinetools,perhapsnoneismoreprominentthan thelimitationofoperatorskills.Withmanualcontrol,thequalityoftheproducti sdirectlyrelatedtoandlimitedtotheskillsoftheoperator.Numericalcontrolrep resentsthefirstmajorstepawayfromhumancontrolofmachinetools.Numericalcontrolmeansthecontrolofmachinetoolsandothermanufact uringsystemsthoughtheuseofprerecorded,writtensymbolicinstructions.Ra therthanoperatingamachinetool,anNCtechnicianwritesaprogramthatissue soperationalinstructionstothemachinetool,Foramachinetooltobenumeric allycontrolled,itmustbeinterfacedwithadeviceforacceptinganddecodingth ep2ogrammedinstructions,knownasareader.Numericalcontrolwasdevelopedtoovercomethelimitationofhumanop erator,andithasdoneso.Numericalcontrolmachinesaremoreaccuratethanm anuallyoperatedmachines,theycanproducepartsmoreuniformly,theyarefas ter,andthelong-runtoolingcostsarelower.ThedevelopmentofNCledtothede velopmentofseveralotherinnovationsinmanufacturingtechnology:1.Electricaldischargemachining.sercutting.3.Electronbeamwelding.Numericalcontrolhasalsomademachinetoolsmoreversatilethantheirmanuallyoperatedpredecessors.AnNCmachinetoolcanautomaticallyproduc eawidevarietyofpar4s,eachinvolvinganassortmentofundertaketheproducti onofproductsthatwouldnothavebeenfeasiblefromaneconomicperspective usingmanuallycontrolledmachinetoolsandprocesses.Likesomanyadvancedtechnologies,NCwasborninthelaboratoriesofthe MassachusettsInstituteofTechnology.TheconceptofNCwasdevelopedinthe early1950swithfundingprovidedbytheU.SAirForce.Initsearlieststages,NCm achineswereabletomakestraightcutsefficientlyandeffectively.However,curvedpathswereaproblembecausethemachinetoolhadtobe programmedtoundertakeaseriesofhorizontalandverticalstepstoproducea curve.Theshorteristhestraightlinesmakingupthestep,thesmootheris4hecu rve.Eachlinesegmentinthestepshadtobecalculated.Thisproblemledtothedevelopmentin1959oftheAutomaticallyProgram medTools(APT)languageforNCthatusesstatementssimilartoEnglishlangua getodefinethepartgeometry,describethecuttingtoolconfiguration,andspe cifythenecessarymotions.ThedevelopmentoftheAPTlanguagewasamajors tepforwardinthefurtherdevelopmentofNCtechnology.TheoriginalNCsyste mwerevastlydifferentfromthoseusedpunchedpaper,whichwaslatertorepla cedbymagneticplastictape.Atapereaderwasusedtointerprettheinstruction swrittenonthetapeforthemachine.Together,all/fthisrepresentedgiantstepf orwardinthecontrolofmachinetools.However,therewereanumberofproble mswithNCatthispointinitsdevelopment.Amajorproblemwasthefragilityofthepunchedpapertapemedium.Itwas commonforthepapercontainingtheprogrammedinstructionstobreakortea rduringamachiningprocess,Thisproblemwasexacerbatedbythefactthateac hsuccessivetimeapartwasproducedonamachinetool,thepapertapecarryin gtheprogrammedinstructionshadtorerunthoughtthereader.Ifitwasnecessa rytoproduce100copiesofagivenpart,itwasalsonecessarytorunthepapertap ethoughtthereader100separatetimes.Fragilepapertapessimplycouldnotwi thstandtherigorsofshopfloorenvironmentandthiskindofrepeateduse.Thisledtothedevelopmentofaspecialmagnetictape.Whereasthepapert apecarriedtheprogrammedinstructionsasaseriesofholespunchedinthetap e,theThismostimportantofthesewasthatitwasdifficultorimpossibletochang etheinstructionsenteredonthetape.Tomakeeventhemostminoradjustment sinaprogramofinstructions,itwasnecessarytointerruptmachiningoperation sandmakeanewtape.Itwasalsostillnecessarytorunthetapethoughtthereade rasmanytimesastherewerepartstobeproduced.Fortunately,computertechn ologybecomearealityandsoonsolvedtheproblemsofNC,associatedwithpun chedpaperandplastictape.Thedevelopmentofaconceptknownasnumericalcontrol(DNC)solvethe paperandplastictapeproblemsassociatedwithnumericalcontrolbysimplyeli minatingtapeasthemediumforcarryingtheprogrammedinstructions.Indire ctnumericalcontrol,machinetoolsaretied,viaadatatransmissionlink,toahost computerandfedtothemachinetoolasneededviathedatatransmissionlinkage.Directnumericalcontrolrepresentedamajorstepforwardoverpunchedta peandplastictape.However,itissubjecttothesamelimitationasalltechnologi esthatdependonahostcomputer.Whenthehostcomputergoesdown,thema chinetoolsalsoexperiencedowntime.Thisproblemledtothedevelopmentofc omputernumericalcontrol.Thedevelopmentofthemicroprocessorallowedforthedevelopmentofpr ogrammablelogiccontrollers(PLC)andmicrocomputers.Thesetwotechnolo giesallowedforthedevelopmentofcomputernumericalcontrol(CNC).WithC NC,eachmachinetoolhasaPLCoramicrocomputerthatservesthesamepurpo se.Thisallowsprogramstobeinputandstoredateachindividualmachinetool. CNCsolvedtheproblemsassociateddowntimeofthehostcomputer,butitintr oducedanotherproblemknownasdatamanagement.Thesameprogrammig htbeloadedontendifferentmicrocomputerswithnocommunicationamongt hem.Thisproblemisintheprocessofbeingsolvedbylocalareanetworksthatco nnectDigitalSignalProcessorsTherearenumeroussituationswhereanalogsignalstobeprocessedinma nyways,likefilteringandspectralanalysis,Designinganaloghardwaretoperfo rmthesefunctionsispossiblebuthasbecomelessandpractical,duetoincrease dperformancerequirements,flexibilityneeds,andtheneedtocutdownondev elopment/testingtime.Itisinotherwordsdifficultpmdesignanaloghardware analysisofsignals.Theactofsamplingansignalintothehatarespecialisedforembeddedsignalprocessingoperations,andsuchaprocessoriscalledaDSP,whichstandsforDi gitalSignalProcessor.TodaytherearehundredsofDSPfamiliesfromasmanym anufacturers,eachonedesignedforaparticularprice/performance/usagegro up.Manyofthelargestmanufacturers,likeTexasInstrumentsandMotorola,off erbothspecialisedDSP’sforcertainfieldslikemotor-controlormodems,and generalhigh-performanceDSP’sthatcanperformbroadrangesofprocessin gtasks.Developmentkitsan`softwarearealsoavailable,andtherearecompani esmakingsoftwaredevelopmenttoolsforDSP’sthatallowstheprogrammer toimplementcomplexprocessingalgorithmsusingsimple“drag‘n’drop ”methodologies.DSP’smoreorlessfallintotwocategoriesdependingontheunderlyingar chitecture-fixed-pointandfloating-point.Thefixed-pointdevicesgenerallyo perateon16-bitwords,whilethefloating-pointdevicesoperateon32-40bitsfl oating-pointwords.Needlesstosay,thefixed-pointdevicesaregenerallychea per.Anotherimportantarchitecturaldifferenceisthatfixed-pointprocessorst endtohaveanaccumulatorarchitec ture,withonlyone“generalpurpose”re gister,makingthemquitetrickytoprogramandmoreimportantly,makingC-c ompilersinherentlyinefficient.Floating-pointDSP’sbehavemorelikecomm ongeneral-purposeCPU’s,withregister-files.TherearethousandsofdifferentDSP’sonthemarket,an ditisdifficulttask findingthemostsuitableDSPforaproject.Thebestwayisprobablytosetupaco nstraintandwishlist,andtrytocomparetheprocessorsfromthebiggestmanufacturersagainstit.The“bigfour”manufacturersofDSPs:TexasInstruments,Motorola,AT &TandAnalogDevices.Digital-to-analogconversionInthecaseofMPEG-Audiodecoding,digitalcompresseddataisfedintoth eDSPwhichperformsthedecoding,thenthedecodedsampleshavetobeconv ertedbackintotheanalogdomain,andtheresultingsignalfedanamplifierorsi milaraudioequipment.Thisdigitaltoanalogconversion(DCA)isperformedby acircuitwiththesamename&DifferentDCA’sprovidedifferentperformance andquality,asmeasuredbyTHD(Totalharmonicdistortion),numberofbits,lin earity,speed,filtercharacteristicsandotherthings.TheTMS320familyDQPofTexasInstrumentsTheTLS320familyconsistsoffixed-point,floating-point,multiprocessor digitalsignalprocessors(D[Ps),andfoxed-pointDSPcontrollers.TMS320DSP haveanarchitecturedesignedspecificallyforreal-timesignalprocessing.The ’F/C240isanumberofthe’C2000DSPplatform,andisoptimizedforcontro la pplications.The’C24xseriesofDSPcontrollerscombinesthisreal-timeproce ssingcapabilitywithcontrollerperipheralstocreateanidealsolutionforcontro lsystemapplications.ThefollowingcharacteristicsmaketheTMS320familyth erightchoiceforawiderangeofprocessingapplications:---Veryflexibleinstructionset---Inherentoperationalflexibility---High-speedperformance---Innovativeparallelarchitecture---CosteffectivenessDeviceswithinagenerationoftheTMS320familyhavethesameCPUstruc turebutdifferenton-chipmemoryandperipheralconfigurations.Spin-offdev icesusenewcombinationsofOn-chipmemoryandperipheralstosatisfyawide rangeofneedsintheworldwideelectronicsmarket.Byintegratingmemoryand peripheralsontoasinglechip,TMS320devicesreducesystemcostsandsavecir cuitboardspace.The16-bit,fixed-point DSPcoreofthe‘C24xdevicesprovidesanalogde signersadigitalsolutionthatdoesnotsacrificetheprecisionandperformance oftheirsystemperformancecanbeenhancedthroughtheuseofadvancedcont rolalgorithmsfortechniquessuchasadaptivecontrol,Kalmanfiltering,andsta tecontrol.The‘C24xDSPcontrollerofferreliabilityandprogrammability.Anal ogcontrolsystems,ontheotherhand,arehardwiredsolutionsandcanexperien ceperformancedegradationduetoaging,componenttolerance,anddrift.Thehigh-speedcentralprocessingunit(CPU)allowsthedigitaldesignert oprocessalgorithmsinrealtimeratherthanapproximateresultswithlook-upt ables.TheinstructionsetoftheseDSPcontrollers,whichincorporatesbothsign alprocessinginstructionsandgeneral-purposecontrolfunctions,coupledwit htheextensivedevelopmenttimeandprovidesthesameeaseofuseastradition al8-and16-bitmicrocontrollers.Theinstructionsetalsoallowsyoutoretainyoursoftwareinvestmentwhenmovingfromothergeneral-purpose‘C2xxgen eration,sourcecodecompatiblewiththe’C2xgeneration,andupwardlysour cecodecompatiblewiththe‘C5xgenerationofDSPsfro mTexasInstruments.The‘C24xarchitectureisalsowell-suitedforprocessingcontrolsignals.I tusesa16-bitwordlengthalongwith32-bitregistersforstoringintermediatere sults,andhastwohardwareshiftersavailabletoscalenumbersindependentlyo ftheCPU.Thiscombinationminimizesquantizationandtruncationerrors,andi ncreasesp2ocessingpowerforadditionalfunctions.Suchfunctionsmightincl udeanotchfilterthatcouldcancelmechanicalresonancesinasystemoranesti mationtechniquethatcouldeliminatestatesensorsinasystem.The‘C24xDSPcontrollerstakeadva ntageofansetofperipheralfunction sthatallowTexasInstrumentstoquicklyconfigurevariousseriesmembersfordi fferentprice/performancepointsorforapplicationoptimization.Thislibraryofbothdigitalandmixed-signalperipheralsincludes:---Timers---Serialcommunicationsports(SCI,SPI)---Analog-to-digitalconverters(ADC)---Eventmanager---Systemprotection,suchaslow-voltageandwatchdogtimerTheDSPcontrollerperipherallibraryiscontinuallygrowingandchanging tosuittheoftomorrow’sembeddedcontrolmarketplace.TheTMS320F/C240isthefirs tstandarddeviceintroducedinthe‘24xseriesofDSPcontrollers.Itsetsthestandardforasingle-chipdigitalmotorcontrolle r.The‘240canexecute20MIPS.Almostallinstructionsareexecutedinasimple cycleof50ns.Thishighperformanceallowsreal-timeexecutionofverycomple 8controlalgorithms,suchasadaptivecontrolandKalmanfilters.Veryhighsam plingratescanalsobeusedtominimizeloopdelays.The‘240hasthearchitecturalfeaturesnecessaryforhigh-speedsignalp rocessinganddigitalcontrolfunctions,andithastheperipheralsneededtopro videasingle-chipsolutio nformotorcontrolapplications.The‘240ismanufac turedusingsubmicronCMOStechnology,achievingalogpowerdissipationrat ing.Alsoincludedareseveralpower-downmodesforfurtherpowersavings.So meapplicationsthatbenefitfromtheadvancedprocessingpowerofthe‘240i nclude:---Industrialmotordrives---Powerinvertersandcontrollers---Automotivesystems,suchaselectronicpowersteering,antilockbrake s,andclimatecontrol---ApplianceandHVACblower/compressormotorcontrols---Printers,copiers,andotherofficeproducts---Tapedrives,magneticopticaldrives,andothermassstorageproducts ---RoboticandCNCmillingmachinesTofunctionasasystemmanager,aDSPmusthaverobuston-chipI/Oando therperipherals.Theeventmanagerofthe‘240isunlikeanyotheravailableonaDSP.Thisapplication-optimizedperipheralunit,coupledwiththehighperfor manceDSPcore,enablestheuseofadvancedcontroltechniquesforhigh-preci sionandhigh-efficiencyfullvariable-speedcontrolofallmotortypes.Includei ntheeventmanagerarespecialpulse-widthmodulation(PWM)generationfu nctions,suchasaprogrammabledead-bandfunctionandaspacevectorPWMs tatemachinefor3-phasemotorsthatprovidesstate-of-the-artmaximumeffic iencyintheswitchingofpowertransistors.Thereindependentupdowntimers,eachwithit’sowncompareregister, supportthegenerationofasymmetric(noncentered)aswellassymmetric(cen tered)PWMwaveforms.Open-LoopandClosed-LoopControlOpen-loopControlSystemsThewordautomaticimpliesthatthereisacertainamountofsophisticatio ninthecontrolsystem.Byautomatic,itgenerallymeansThatthesystemisusuall ycapableofadaptingtoavarietyofoperatingconditionsandisabletorespondt oaclassofinputssatisfactorily.However,notanytypeofcontrolsystemhasthea ually,theautomaticfeatureisachievedbyfeed.gthefeedbackstructure,itiscalledanopen-loopsystem,whichisthesimp lestandmosteconomicaltypeofcontrolsystem.inaccuracyliesinthefactthato nemaynotknowtheexactcharacteristicsofthefurther,whichhasadefinitebea ringontheindoortemperature.Thisalcopointstoanimportantdisadvantageo ftheperformanceofanopen-loopcontrolsystem,inthatthesystemisnotcapableofadaptingtovariationsinenvironmentalconitionsortoexternaldisturban ces.Inthecaseofthefurnacecontrol,perhapsanexperiencedpersoncanprovi decontrolforacertaindesiredtemperatureinthehouse;butidthedoorsorwin dowsareopenedorclosedintermittentlyduringtheoperatingperiod,thefinal temperatureinsidethehousewillnotbeaccuratelyregulatedbytheopen-loop control.Anelectricwashingmachineisanothertypicalexampleofanopen-loops ystem,becausetheamountofwashtimeisentirelydeterminedbythejudgmen tandestimationofthehumanoperator.Atrueautomaticelectricwashingmach ineshouldhavethemeansofcheckingthecleanlinessoftheclothescontinuous lyandturnitsedtoffwhenthedesireddegisedofcleanlinessisreached.Closed-LoopControlSystemsWhatismissingintheopen-loopcontrolsystemformoreaccurateandmo readaptablecontrolisalinkorfeedbackfromtheoutputtotheinputofthesyste m.Inordertoobtainmoreaccuratebontrol,thecontrolledsignalc(t)mustbefe dbackandcomparedwiththereferenceinput,andanactuatingsignalproporti onaltothedifferenceoftheoutputandtheinputmustbesentthroughthesyste mtocorrecttheerror.Asystemwithoneormorefeedbackpat(slikethatjustdesc ribediscalledaclosed-loopsystem.humanbeingareprobablythemostcompl exandsophisticatedfeedbackcontrolsysteminexistence.Ahumanbeingmay beconsideredtobeacontrolsystemwithmanyinputsandoutputs,capableofc arryingouthighlycomplexoperations.Toillustratethehumanbeingasafeedbackcontrolsystem,letusconsidert hattheobjectiveistoreachforanobjectonaperformthetask.Theeyesserveasa sensingdevicewhichfeedsbackcontinuouslythepositionofthehand.Thedist ancebetweenthehandandtheobjectistheerror,whichiseventuallybroughtto zeroasthehandreachertheobject.Thisisatypicalexampleofclosed-loopcontr ol.However,ifoneistoldtoreachfortheobjectandthenisblindolded,onecano nlyreachtowardtheobjectbyestimatingitsexactposition.ItisAsantherillustra tiveexampleofaclosed-loopcontrolsystem,showstheblockdiagramoftheru ddercontrolsystemofThebasicalementsandtheblocadiagramofaclosed-loo pcontrolsystemareshowninfig.Ingeneral,theconfigurationofafeedbackcon trolsystemmaynotbeconstrainedtothatoffig&.Incomplexsystemstheremay bemultitudeoffeedbackloopsandelementblocks.数控在先进制造技术领域最根本的观念之壹是数控（NC）。
数控机床外文翻译1
外文翻译机床数控改造_Machine tool numerical control reformsFirst, CNC systems and the development trend of history一、数控系统发展简史及趋势1946 birth of the world's first electronic computer, which shows that human beings created to enhance and replace some of the mental work tools. It and human agriculture, industrial society in the creation of those who merely increase compared to manual tools, from a qualitative leap for mankind's entry into the information society laid the foundation. Six years later, in 1952, computer technology applied to the machine in the United States was born first CNC machine tools. Since then, the traditional machine produced a qualitative change. Nearly half a century since the CNC system has experienced two phases and six generations of development.1946年诞生了世界上第一台电子计算机，这表明人类创造了可增强和部分代替脑力劳动的工具。
文献翻译-数控机床
附录1数控机床是一种以数字量作为指令信息、形式，通过电子计算机或专用计算机装置控制的机床，是在机电一体化技术的基础上发展起来的一种灵活而高效的自动化机床，在机械行业中得到了日益广泛的应用数控机床是按照预定程序自动工作的，一般情况下工作过程不需要人工干预，这就消除了操作者认为生产的误差。
在设计制造设备主机时，通常采取了许多措施，使数控设备的机械部分达到较高的精度。
数控装置的脉冲当量可达0.01—0.00002mm,同时，可以通过实现检测反馈修正误差或补偿来获得更高的精度。
因此，数控机床可以获得比机床本身精度更高的加工精度。
尤其提高了同批零件生产的一致性，使产品质量获得稳定的控制。
数控机床的工作是按预先编制好的加工程序自动连续完成的，操作者除输入加工程序及相关的操作之外，不需进行繁重的重复手工操作，劳动条件和劳动强度大为改善。
数控机床与普通机床相比具有许多优点，其应用范围正在不断扩大，但目前它并不能完全替代普通机床，也还不能以最经济的方式解决机械加工中的所有问题。
在实际选用时，一定要充分考虑其技术经济效益。
由于数控机床的自动化程度、生产效率都很高，可最大限度地减小操作工人。
因此，大批量生产的零件采用数控机床加工，在经济上也是可行的。
车床主要是用于车削加工，在机床上一般可以加工各种回转表面，如内外圆柱面、圆锥面、成形回转表面及螺纹表面等。
在数控车床上还可以加工高精度的曲面与端面螺纹。
用的刀具主要是车刀、各种孔加工工具（钻头、铰刀、镗刀等）及螺纹刀具。
车床主要用于加工各种轴类、套筒类和盘类零件上的回转表面。
数控车床加工零件的尺寸精度可达IT5~IT6，表面粗糙度可达 1.6μm以下。
数控车床的种类很多，各种卧式车床都有数控化的。
数控车床主要可分为数控卧式车床、数控立式车床和数控专用车床（数控凸轮车床、数控曲轴车床、数控丝杠车床等）；或分为普通数控车床和车削加工中心。
现在，数控车床技术还在不断向前发展着。
机械类数控外文翻译外文文献英文文献数控
Numerical ControlOne of the most fundamental concepts in the area of advanced manufacturing technologies is numerical control (NC).Prior to the advent of NC, all machine tools were manual operated and controlled. Among the many limitations associated with manual control machine tools, perhaps none is more prominent than the limitation of operator skills. With manual control, the quality of the product is directly related to and limited to the skills of the operator . Numerical control representsthe first major step away from human control of machine tools.Numerical control means the control of machine tools and other manufacturing systems though the use of prerecorded, written symbolic instructions. Rather than operating a machine tool, an NC technician writes a program that issues operational instructions to the machine tool, For a machine tool to be numerically controlled , it must be interfaced with a device for accepting and decoding the p2ogrammed instructions, known as a reader.Numerical control was developed to overcome the limitation of human operator , and it has done so . Numerical control machines are more accurate than manually operated machines , they can produce parts more uniformly , they are faster, and the long-run tooling costs are lower . The development of NC led to the development of several other innovations in manufacturing technology:1.Electrical discharge machining.ser cutting.3.Electron beam welding.Numerical control has also made machine tools more versatile than their manually operated predecessors.An NC machine tool can automatically produce a wide variety of par4s , each involving an assortment of undertake the production of products that would not have been feasible from an economic perspective using manually controlled machine tools and processes.Like so many advanced technologies , NC was born in the laboratories of the Massachusetts Institute of Technology . The concept of NC was developed in the early 1950s with funding provided by the U.S Air Force .In its earliest stages , NC machines were able to make straight cuts efficiently and effectively.However ,curved paths were a problem because the machine tool had to be programmed to undertake a series of horizontal and vertical steps to produce a curve. The shorter is the straight lines making up the step ,the smoother is 4he curve . Each line segment in the steps had to be calculated.This problem led to the development in 1959 of the Automatically Programmed Tools (APT) language for NC that uses statementssimilar to English language to define the part geometry, describe the cutting tool configuration, and specify the necessary motions. The development of the APT language was a major step forward in the further development of NC technology. The original NC system were vastly different from those used punched paper , which was later to replaced by magnetic plastic tape .A tape reader was used to interpret the instructions written on the tape for the machine .Together, all /f this representedgiant step forward in the control of machine tools . However ,there were a number of problems with NC at this point in its development.A major problem was the fragility of the punched paper tape medium . It was common for the paper containing the programmed instructions to break or tear during a machining process, This problem was exacerbated by the fact that each successive time a part was produced on a machine tool, the paper tape carrying the programmed instructions had to rerun thought the reader . If itwas necessary to produce 100 copies of a given part , it was also necessary to run the paper tape thought the reader 100 separate times . Fragile paper tapes simply could not withstand the rigorsof shop floor environment and this kind of repeated use.This led to the development of a special magnetic tape . Whereas the paper tape carried the programmed instructions as a series of holes punched in the tape , theThis most important of these was that it was difficult or impossible to change the instructions entered on the tape . To make even the most minor adjustments in a program of instructions, it was necessary to interrupt machining operations and make a new tape. It was also still necessary to run the tape thought the reader as many times as there were parts to be produced . Fortunately, computer technology become a reality and soon solved the problems of NC, associated with punched paper and plastic tape.The development of a concept known as numerical control (DNC) solve the paper and plastic tape problems associatedwith numerical control by simply eliminating tape as the medium for carrying the programmed instructions . In direct numerical control, machine tools are tied, via a data transmission link, to a host computer and fed to the machine tool as needed via the data transmission linkage. Direct numerical control represented a major step forward over punched tape and plastic tape. However ,it is subject to the same limitation as all technologies that depend on a host computer. When the host computer goes down , the machine tools also experience down time . This problem led to the development of computer numerical control.The development of the microprocessor allowed for the development of programmable logic controllers (PLC) and microcomputers . These two technologies allowed for the development of computer numerical control (CNC).With CNC , each machine tool has a PLC or a microcomputer that serves the same purpose. This allows programs to be input and stored at each individual machine tool. CNC solved the problems associated downtime of the host computer , but it introduced another problem known as data management . The same program might be loaded on ten different microcomputers with no communication among them. This problem is in the process of being solved by local area networks that connectDigital Signal ProcessorsThere are numerous situations where analog signals to be processed in many ways, likefiltering and spectral analysis , Designing analog hardware to perform these functions is possible but has become less and practical, due to increased performance requirements, flexibility needs , and the need to cut down on development/testing time .It is in other words difficult pm design analog hardware analysis of signals.The act of sampling an signal into thehat are specialised for embedded signal processing operations , and such a processor is called a DSP, which stands for Digital Signal Processor . Today there are hundreds of DSP families from as many manufacturers, each one designed for a particular price/performance/usagegroup. Many of the largest manufacturers, like Texas Instruments and Motorola, offer both specialised DSP for certain'fieslds like motor -control or modems ,and general highp- erformance DSP ' s that can perform broad ranges of processingtasks. Development kits an' software are also available , and there are companies making software development tools for DSP' sth at allows the programmer to implement complex processing algorithms using simple “drag ‘n' drop ” methodologies.DSP's more or less fall into two categories depending on the underlying architecture-fixed-point and floating-point. The fixed-point devices generally operate on 16-bit words, while the floating-point devices operate on 32-40 bits floating-point words. Needless to say , the fixed-point devices are generally cheaper . Another important architectural difference is that fixed-point processors tend to have an accumulator architecture, with only one “generaplurpose ”register , making them quite tricky to program and more importantly ,making C-compilers inherently inefficient. Floating-point DSP'sbehave more like common general-purpose CPU's ,with re g i s-tfei l er s .There are thousands of different DSP 's on the market, and it is difficult task finding themost suitable DSP for a project. The best way is probably to set up a constraint and wishlist, and try to compare the processors from the biggest manufacturers against it.The “big four ” manufacturers of DSPs: Texas Instruments, Motorola, AT&T and Analog Devices.Digital-to-analog conversionIn the case of MPEG-Audio decoding , digital compressed data is fed into the DSP which performs the decoding , then the decoded samples have to be converted back into the analog domain , and the resulting signal fed an amplifier or similar audio equipment . This digital to analog conversion (DCA) is performed by a circuit with the same name & Different DCA provide different performance and quality , as measured by THD (Total harmonic distortion ), number of bits,linearity , speed, filter characteristics and other things.The TMS320 family DQP of Texas InstrumentsThe TLS320family consists of fixed-point, floating-point, multiprocessor digital signal processors (D[Ps) , and foxed-point DSP controllers. TMS320 DSP have an architecture designed specifically for real-time signal processing . The' F/C240 is a number of the 'C2000DSP platform , and is optimized for control applications. The 'C24x series o controllers combines this real-time processing capability with controller peripherals to create an ideal solution for control system applications. The following characteristics make the TMS320 family the right choice for a wide range of processing applications:--- Very flexible instruction set--- Inherent operational flexibility---High-speed performance---Innovative parallel architecture---Cost effectivenessDevices within a generation of the TMS320 family have the same CPU structure but differenton-chip memory and peripheral configurations. Spin-off devices use new combinations of On-chip memory and peripherals to satisfy a wide range of needs in the worldwide electronics market. By integrating memory and peripherals onto a single chip , TMS320 devices reduce system costs and save circuit board space.The 16-bit ,fixed-point DSP core of the ‘C24xdevicesprovides analog designers a digital solution that does not sacrifice the precision and performance of their system performance can be enhanced through the use of advanced control algorithms for techniquessuch as adaptive control , Kalman filtering , andstate control. The ‘ C24x DSP controller offer reliability and programmability . Analog control systems, on the other hand ,are hardwiredsolutions and can experience performance degradation due to aging , component tolerance, and drift.The high-speed central processing unit (CPU) allows the digital designer to process algorithms in real time rather than approximate results with look-up tables. The instruction set of these DSP controllers, which incorporates both signal processing instructions and general-purpose control functions, coupled with the extensive development time and provides the same ease of use astraditional 8-and 16-bit microcontrollers. The instruction set also allows you to retain your software investment when moving from other general-purpose‘ C2xx generation ,source code compatible with the ' C2gxeneration , and upwardly source code compatible with the ‘ C5x generation of DSPs from Texas Instruments.The ‘C24x architecture is also w-eslul ited for processing control signals. It uses a 16-bit word length along with 32-bit registers for storing intermediate results, and has two hardware shifters available to scale numbers independently of the CPU . This combination minimizes quantization and truncation errors, and increases p2ocessing power for additional functions. Such functions might include a notch filter that could cancel mechanical resonancesin a system or an estimation technique that could eliminate state sensors in a system.The ‘ C24xDSP controllers take advantage of an set of peripheraful nctions that allow Texas Instruments to quickly configure various series members for different price/ performance points or for application optimization.This library of both digital and mixed-signal peripherals includes:---Timers---Serial communications ports (SCI,SPI)---Analog-to-digital converters(ADC)---Event manager---System protection, such as low-voltage and watchdog timerThe DSP controller peripheral library is continually growing and changing to suit the of tomorrow ' s embedded control matrpkleace.The TMS320F/C240 is the first standard device introduced in the ‘ 24x series of DScontrollers. It sets the standard for a singlec-hip digital motor controller. The ‘ 240 can execute 20 MIPS. Almost all instructions are executed in a simple cycle of 50 ns . This high performance allows real-time execution of very comple8 control algorithms, such as adaptive control and Kalman filters. Very high sampling rates can also be used to minimize loop delays.The ‘ 240 has the architectural features necessfaorryhigh-speed signal processing anddigital control functions, and it has the peripherals needed to provide a single-chip solution for motor control applications. The ‘ 240is manufactured using submicron CMOS technology, achieving a log power dissipation rating . Also included are several power-down modes for further power savings. Some applications that benefit from the advanced processing power of the ‘ 240 include: ---Industrial motor drives---Power inverters and controllers---Automotive systems, such as electronic power steering , antilock brakes, and climate control---Appliance and HVAC blower/ compressor motor controls---Printers, copiers, and other office products---Tape drives, magnetic optical drives, and other mass storage products---Robotic and CNC milling machinesTo function as a system manager, a DSP must have robust on-chip I/O and other peripherals. The event manager of the ‘ 240is unlike any other available on a DSP . This application-optimized peripheral unit , coupled with the high performance DSP core, enables the use of advanced control techniques for high-precision and high-efficiency full variable-speed control of all motor types.Include in the event manager are special pulse-width modulation (PWM) generation functions, such as a programmable dead-band function and a space vector PWM state machine for 3-phase motors that provides state-of-the-art maximum efficiency in the switching of power transistors.There independent up down timers, each with it 'oswn compare register, support the generation of asymmetric (noncentered) as well as symmetric (centered) PWM waveforms.Open-Loop and Closed-Loop ControlOpen-loop Control SystemsThe word automatic implies that there is a certain amount of sophistication in the control system. By automatic, it generally means That the system is usually capable of adapting to avariety of operating conditions and is able to respond to a class of inputs satisfactorily . However , not any type of control system has the automatic feature. Usually , the automatic feature is achieved by feed.g the feedback structure, it is called an open-loop system , which is the simplest and most economical type of control system.inaccuracy lies in the fact that one may not know the exact characteristics of the further ,which has a definite bearing on the indoor temperature. This alco points to an important disadvantageof the performance of an open -loop control system, in that the system is not capable of adapting to variations in environmental conitions or to external disturbances. In the case of the furnace control, perhaps an experienced person can provide control for a certain desired temperature in the house; but id the doors or windows are opened or closed intermittently during the operating period, the final temperature inside the house will not be accurately regulated by the open-loop control.An electric washing machine is another typical example of an open-loop system , because the amount of wash time is entirely determined by the judgment and estimation of the human operator . A true automatic electric washing machine should have the means of checking the cleanliness of the clothes continuously and turn itsedt off when the desired degised of cleanliness is reached.Closed-Loop Control SystemsWhat is missing in the open-loop control system for more accurate and more adaptable control is a link or feedback from the output to the input of the system . In order to obtain more accurate bontrol, the controlled signal c(t) must be fed back and compared with the reference input , and an actuating signal proportional to the difference of the output and the input must be sent through the system to correct the error. A system with one or more feedback pat(s like that just described is called a closed-loop system. human being are probably the most complex and sophisticated feedback control system in existence. A human being may be considered to be a control system with many inputs and outputs, capable of carrying out highly complex operations.To illustrate the human being as a feedback control system , let us consider that the objective is to reach for an object on aperform the task. The eyes serve as a sensing device which feeds back continuously the position of the hand . The distance between the hand and the object is the error , which is eventually brought to zero as the hand reacher the object. This is a typical example of closed-loop control. However , if one is told to reach for the object and then is blindolded, one can only reach toward the object by estimating its exact position. It isAs anther illustrative example of a closed-loop control system, shows the block diagram of the rudder control system ofThe basic alements and the bloca diagram of a closed-loop control system are shown in fig. In general , the configuration of a feedback control system may not be constrained to that of fig & . In complex systems there may be multitude of feedback loops and element blocks.数控在先进制造技术领域最根本的观念之一是数控（ NC。
数控机床外文文献翻译、中英文翻译
数控机床外文文献翻译、中英文翻译原文一CNC machine toolsOutdate, J. and Joe, J. Configuration Synthesis of Machining Centers with Tool，JohnWiley & sons, 2001While the specific intention and application for CNC machines vary from one machine type to another, all forms of CNC have common benefits. Here are but a few of the more important benefits offered by CNC equipment.The first benefit offered by all forms of CNC machine tools is improved automation. The operator intervention related to producing work pieces can be reduced or eliminated. Many CNC machines can run unattended during their entire machining cycle, freeing the operator to do other tasks. This gives the CNC user several side benefits including reduced operator fatigue, fewer mistakes caused by human error, and consistent and predictable machining time for each work piece. Since the machine will be running under program control, the skill level required of the CNC operator (related to basic machining practice) is also reduced as compared to a machinist producing work pieces with conventional machine tools.The second major benefit of CNC technology is consistent and accurate work pieces. T oday's CNC machines boast almost unbelievable accuracy and repeatability specifications. This means that once a program is verified, two, ten, or one thousand identical work pieces can be easily produced with precision and consistency.A third benefit offered by most forms of CNC machine toolsis flexibility. Since these machines are run from programs, running a different workpiece is almost as easy as loading a different program. Once a program has been verified and executed for one production run, it can be easily recalled the next time the workpiece is to be run. This leads to yet another benefit, fast change over. Since these machines are very easy to set up and run, and since programs can be easily loaded, they allow very short setup time. This is imperative with today's just-in-time (JIT) product requirements.Motion control - the heart of CNCThe most basic function of any CNC machine is automatic, precise, and consistent motion control. Rather than applying completely mechanical devices to cause motion as is required on most conventional machine tools, CNC machines allow motion control in a revolutionary manner2. All forms of CNC equipment have two or more directions of motion, called axes. These axes can be precisely and automatically positioned along their lengths of travel. The two most common axis types are linear (driven along a straight path) and rotary (driven along a circular path).Instead of causing motion by turning cranks and handwheels as is required on conventional machine tools, CNC machines allow motions to be commanded through programmed commands. Generally speaking, the motion type (rapid, linear, and circular), the axes to move, the amount of motion and the motion rate (federate) are programmable with almost all CNC machine tools.A CNC command executed within the control tells the drive motor to rotate a precise number of times. The rotation of the drive motor in turn rotates the ball screw.And the ball screw drives the linear axis (slide). A feedbackdevice (linear scale) on the slide allows the control to confirm that the commanded number of rotations has taken place3. Refer to fig.1.fig.1 typical drive system of a CNC machine toolThough a rather crude analogy, the same basic linear motion can be found on a common table vise. As you rotate the vise crank, you rotate a lead screw that, in turn, drives the movable jaw on the vise. By comparison, a linear axis on a CNC machine tool is extremely precise. The number of revolutions of the axis drive motor precisely controls the amount of linear motion along the axis.How axis motion is commanded - understanding coordinate systemsIt would be infeasible for the CNC user to cause axis motion by trying to tell each axis drive motor how many times to rotate in order to command a given linear motion amount4. (This would be like having to figure out how many turns of the handle on a table vise will cause the movable jaw to move exactly one inch!) Instead, all CNC controls allow axis motion to be commanded in a much simpler and more logical way by utilizing some form of coordinate system. The two most popular coordinate systems used with CNC machines are the rectangular coordinate system and the polar coordinate system. By far, the more popular of these two is the rectangular coordinate system.The program zero point establishes the point of reference for motion commands in a CNC program. This allows the programmer to specify movements from a common location. If program zero is chosen wisely, usually coordinates needed forthe program can be taken directly from the print.With this technique, if the programmer wishes the tool to be sent to a position one inch to the right of the program zero point, X1.0 is commanded. If the programmer wishes the tool to move to a position one inch above the program zero point, Y1.0 is commanded. The control will automatically determine how many times to rotate each axis drive motor and ball screw to make the axis reach the commanded destination point . This lets the programmer command axis motion in a very logical manner. Refer to fig.2, 3.fig.2, 3.Understanding absolute versus incremental motionAll discussions to this point assume that the absolute mode of programming is used6. The most common CNC word used to designate the absolute mode is G90. In the absolute mode, the end points for all motions will be specified from the program zero point. For beginners, this is usually the best and easiest method of specifying end points for motion commands. However, there is another way of specifying end points for axis motion.In the incremental mode (commonly specified by G91), endpoints for motions are specified from the tool's current position, not from program zero. With this method of commanding motion, the programmer must always be asking "How far should I move the tool?" While there are times when the incremental mode can be very helpful, generally speaking, this is the more cumbersome and difficult method of specifying motion and beginners should concentrate on using the absolute mode.Be careful when making motion commands. Beginners have the tendency to think incrementally. If working in the absolute mode (as beginners should), the programmer should always be asking "To what position should the tool be moved?" This position is relative to program zero, NOT from the tools current position.Aside from making it very easy to determine the current position for any command, another benefit of working in the absolute mode has to do with mistakes made during motion commands. In the absolute mode, if a motion mistake is made in one command of the program, only one movement will be incorrect. On the other hand, if a mistake is made during incremental movements, all motions from the point of the mistake will also be incorrect.Assigning program zeroKeep in mind that the CNC control must be told the location of the program zero point by one means or another. How this is done varies dramatically from one CNC machine and control to another8. One (older) method is to assign program zero in the program. With this method, the programmer tells the control how far it is from the program zero point to the starting position of the machine. This is commonly done with a G92 (or G50) command at least at the beginning of the program and possiblyat the beginning of each tool.Another, newer and better way to assign program zero is through some form of offset. Refer to fig.4. Commonly machining center control manufacturers call offsets used to assign program zero fixture offsets. Turning center manufacturers commonly call offsets used to assign program zero for each tool geometry offsets.fig.4 assign program zero through G54Flexible manufacturing cellsA flexible manufacturing cell (FMC) can be considered as a flexible manufacturing subsystem. The following differences exist between the FMC and the FMS:1.An FMC is not under the direct control of thecentral computer. Instead, instructions from the centralcomputer are passed to the cell controller.2.The cell is limited in the number of part families itcan manufacture.The following elements are normally found in an FMC:Cell controllerProgrammable logic controller (PLC)More than one machine toolA materials handling device (robot or pallet)The FMC executes fixed machining operations with parts flowing sequentially between operations.High speed machiningThe term High Speed Machining (HSM) commonly refers to end milling at high rotational speeds and high surface feeds. For instance, the routing of pockets in aluminum airframe sections with a very high material removal rate1. Refer to fig.5 for the cutting data designations and for mulas. Over the past 60 years, HSM has been applied to a wide range of metallic and non-metallic workpiece materials, including the production of components with specific surface topography requirements and machining of materials with hardness of 50 HRC and above. With most steel components hardened to approximately 32-42 HRC, machining options currently include:Fig.5 cutting datarough machining and semi-finishing of the material in its soft (annealed) condition heat treatment to achieve the final required hardness = 63 HRC machining of electrodes and Electrical Discharge Machining (EDM) of specific parts of dies and moulds (specifically small radii and deep cavities with limited accessibility for metal cutting tools) finishing and super-finishing of cylindrical/flat/cavity surfaces with appropriate cemented carbide, cermets, solid carbide, mixed ceramic or polycrystalline cubic boron nitride (PCBN)For many components, the production process involves acombination of these options and in the case of dies and moulds it also includes time consuming hand finishing. Consequently, production costs can be high and lead times excessive.It is typical in the die and mould industry to produce one or just a few tools of the same design. The process involves constant changes to the design, and because of these changes there is also a corresponding need for measuring and reverse engineering.The main criteria are the quality level of the die or mould regarding dimensional, geometric and surface accuracy. If the quality level after machining is poor and if it cannot meet the requirements, there will be a varying need of manual finishing work. This work produces satisfactory surface accuracy, but it always has a negative impact on the dimensional and geometric accuracy.One of the main aims for the die and mould industry has been, and still is, to reduce or eliminate the need for manual polishing and thus improve the quality and shorten the production costs and lead times.Main economical and technical factors for the development of HSMSurvivalThe ever increasing competition in the marketplace is continually setting new standards. The demands on time and cost efficiency is getting higher and higher. This has forced the development of new processes and production techniques to take place. HSM provides hope and solutions...MaterialsThe development of new, more difficult to machine materials has underlined the necessity to find new machining solutions.The aerospace industry has its heat resistant and stainless steel alloys. The automotive industry has different bimetal compositions, Compact Graphite Iron and an ever increasing volume of aluminum3. The die and mould industry mainly has to face the problem of machining high hardened tool steels, from roughing to finishing.QualityThe demand for higher component or product quality is the result of ever increasing competition. HSM, if applied correctly, offers a number of solutions in thisarea. Substitution of manual finishing is one example, which is especially important on dies and moulds or components with a complex 3D geometry.ProcessesThe demands on shorter throughput times via fewer setups and simplified flows (logistics) can in most cases, be solved by HSM. A typical target within the die and mould industry is to completely machine fully hardened small sized tools in one setup. Costly and time consuming EDM processes can also be reduced or eliminated with HSM.Design & developmentOne of the main tools in today's competition is to sell products on the value of novelty. The average product life cycle on cars today is 4 years, computers and accessories 1.5 years, hand phones 3 months... One of the prerequisites of this development of fast design changes and rapid product development time is the HSM technique.Complex productsThere is an increase of multi-functional surfaces on components, such as new design of turbine blades giving newand optimized functions and features. Earlier designs allowed polishing by hand or with robots (manipulators). Turbine blades with new, more sophisticated designs have to be finished via machining and preferably by HSM . There are also more and more examples of thin walled workpiece that have to be machined (medical equipment, electronics, defense products, computer parts).Production equipmentThe strong development of cutting materials, holding tools, machine tools, controls and especially CAD/CAM features and equipment, has opened possibilities that must be met with new production methods and techniques5.Definition of HSMSalomon's theory, "Machining with high cutting speeds..." on which, in 1931, took out a German patent, assumes that "at a certain cutting speed (5-10 times higher than in conventional machining), the chip removal temperature at the cutting edge will start to decrease...".See fig.6.Fig.6 chip removal temperature as a result of the cutting speedGiven the conclusion:" ... seems to give a chance to improve productivity in machining with conventional tools at high cutting speeds..."Modern research, unfortunately, has not been able to verifythis theory totally. There is a relative decrease of the temperature at the cutting edge that starts at certain cutting speeds for different materials.The decrease is small for steel and cast iron. But larger for aluminum and other non-ferrous metals. The definition of HSM must be based on other factors.Given today's technology, "high speed" is generally accepted to mean surface speeds between 1 and 10 kilometers perminute, or roughly 3 300 to 33 000 feet per minute. Speeds above 10 km/min are in the ultra-high speed category, and are largely the realm of experimental metal cutting. Obviously, the spindle rotations required to achieve these surface cutting speeds are directly related to the diameter of the tools being used. One trend which is very evident today is the use of very large cutter diameters for these applications - and this has important implications for tool design.There are many opinions, many myths and many different ways to define HSM. Maintenance and troubleshooting Maintenance for a horizontal MCThe following is a list of required regular maintenance for a Horizontal Machining Center as shown in fig.7. Listed are the frequency of service, capacities, and type of fluids required. These required specifications must be followed in order to keep your machine in good working order and protect your warranty.Fig. 7 horizontal machining centerDailyTop off coolant level every eight hour shift (especially during heavy TSC usage).Check way lube lubrication tank level.Clean chips from way covers and bottom pan.Clean chips from tool changer.Wipe spindle taper with a clean cloth rag and apply light oil.WeeklyCheck for proper operation of auto drain on filter regulator. See fig. 8Fig. 8 way lube and pneumaticsOn machines with the TSC option, clean the chip basket on the coolant tank.Remove the tank cover and remove any sediment inside the tank. Be careful to disconnect the coolant pump from the controller and POWER OFF the control before working on the coolant tank. Do this monthly for machines without the TSC option.Check air gauge/regulator for 85 psi.For machines with the TSC option, place a dab of grease on the V-flange of tools. Do this monthly for machines without the TSC option.Clean exterior surfaces with mild cleaner. DO NOT usesolvents.Check the hydraulic counterbalance pressure according to the machine's specifications.Place a dab of grease on the outside edge of the fingers of the tool changer and run through all tools".MonthlyCheck oil level in gearbox. Add oil until oil begins dripping from over flow tube at bottom of sump tank.Clean pads on bottom of pallets.Clean the locating pads on the A-axis and the load station. This requires removing the pallet.Inspect way covers for proper operation and lubricate with light oil, if necessary.Six monthsReplace coolant and thoroughly clean the coolant tank.Check all hoses and lubrication lines for cracking.AnnuallyReplace the gearbox oil. Drain the oil from the gearbox, and slowly refill it with 2 quarts of Mobil DTE 25 oil.Check oil filter and clean out residue at bottom for the lubrication chart.Replace air filter on control box every 2 years.Mineral cutting oils will damage rubber based components throughout the machine.TroubleshootingThis section is intended for use in determining the solution to a known problem. Solutions given are intended to give the individual servicing the CNC a pattern to follow in, first, determining the problem's source and, second, solving the problem.Use common senseMany problems are easily overcome by correctly evaluating the situation. All machine operations are composed of a program, tools, and tooling. You must look at all three before blaming one as the fault area. If a bored hole is chattering because of an overextended boring bar, don't expect the machine to correct the fault.Don't suspect machine accuracy if the vise bends the part. Don't claim hole miss-positioning if you don't first center-drill the hole.Find the problem firstMany mechanics tear into things before they understand the problem, hoping that it will appear as they go. We know this from the fact that more than half of all warranty returned parts are in good working order. If the spindle doesn't turn, remember that the spindle is connected to the gear box, which is connected to the spindle motor, which is driven by the spindle drive, which is connected to the I/O BOARD, which is driven by the MOCON, which is driven by the processor. The moral here is doing replace the spindle drives if the belt is broken. Find the problem first; don't just replace the easiest part to get to.Don tinker with the machineThere are hundreds of parameters, wires, switches, etc., that you can change in this machine. Don't start randomly changing parts and parameters. Remember, there is a good chance that if you change something, you will incorrectly install it or break something else in the process6. Consider for a moment changing the processor's board. First, you have to download all parameters, remove a dozen connectors, replace the board, reconnect and reload, and if you make one mistake or bend one tiny pin itWON'T WORK. You always need to consider the risk of accidentally damaging the machine anytime you work on it. It is cheap insurance to double-check a suspect part before physically changing it. The less work you do on the machine the better.译文一数控机床虽然各种数控机床的功能和应用各不相同，但它们有着共同的优点。
机械类数控车床外文翻译外文文献英文文献车床.doc
LathesLathes are machine tools designed primarily to do turning, facing and boring, Very little turning is done on other types of machine tools, and none can do it with equal facility. Because lathes also can do drilling and reaming, their versatility permits several operations to be done with a single setup of the work piece. Consequently, more lathes of various types are used in manufacturing than any other machine tool.The essential components of a lathe are the bed, headstock assembly, tailstock assembly, and the leads crew and feed rod.The bed is the backbone of a lathe. It usually is made of well normalized or aged gray or nodular cast iron and provides s heavy, rigid frame on which all the other basic components are mounted. Two sets of parallel, longitudinal ways, inner and outer, are contained on the bed, usually on the upper side. Some makers use an inverted V-shape for all four ways, whereas others utilize one inverted V and one flat way in one or both sets, They are precision-machined to assure accuracy of alignment. On most modern lathes the way are surface-hardened to resist wear and abrasion, but precaution should be taken in operating a lathe to assure that the ways are not damaged. Any inaccuracy in them usually means that the accuracy of the entire lathe is destroyed.The headstock is mounted in a foxed position on the inner ways, usually at the left end of the bed. It provides a powered means of rotating the word at various speeds . Essentially, it consists of a hollow spindle, mounted in accurate bearings, and a set of transmission gears-similar to a truck transmission—through which the spindle can be rotated at a number of speeds. Most lathes provide from 8 to 18 speeds, usually in a geometric ratio, and on modern lathes all the speeds can be obtained merely by moving from two to four levers. An increasing trend is to provide a continuously variable speed range through electrical or mechanical drives.Because the accuracy of a lathe is greatly dependent on the spindle, it is of heavy construction and mounted in heavy bearings, usually preloaded tapered roller or ball types. The spindle has a hole extending through its length, through which long bar stock can be fed. The size of maximum size of bar stock that can be machined when the material must be fed through spindle.The tailsticd assembly consists, essentially, of three parts. A lower casting fits on the inner ways of the bed and can slide longitudinally thereon, with a means for clamping the entire assembly in any desired location, An upper casting fits on the lower one and can be moved transversely upon it, on some type of keyed ways, to permit aligning the assembly is the tailstock quill. This is a hollow steel cylinder, usually about 51 to 76mm(2to 3 inches) in diameter, that can be moved several inches longitudinally in and out of the upper casting by means of a hand wheel and screw.The size of a lathe is designated by two dimensions. The first is known as the swing. This is the maximum diameter of work that can be rotated on a lathe. It is approximately twice the distance between the line connecting the lathe centers and the nearest point on the ways, The second size dimension is the maximum distance between centers. The swing thus indicates the maximum work piece diameter that can be turned in the lathe, while the distance between centers indicates the maximum length of work piece that can be mounted between centers.Engine lathes are the type most frequently used in manufacturing. They are heavy-duty machine tools with all the components described previously and have power drive for all tool movements except on the compound rest. They commonly range in size from 305 to 610 mm(12 to 24 inches)swing and from 610 to 1219 mm(24 to 48 inches) center distances, but swings up to 1270 mm(50 inches) and center distances upto 3658mm(12 feet) are not uncommon. Most have chip pans and a built-in coolant circulating system. Smaller engine lathes-with swings usually not over 330 mm (13 inches ) –also are available in bench type, designed for the bed to be mounted on a bench on a bench or cabinet.Although engine lathes are versatile and very useful, because of the time required for changing and setting tools and for making measurements on the work piece, thy are not suitable for quantity production. Often the actual chip-production tine is less than 30% of the total cycle time. In addition, a skilled machinist is required for all the operations, and such persons are costly and often in short supply. However, much of the operator’s time is consumed by simple, repetitious adjustments and in watching chips being made. Consequently, to reduce or eliminate the amount of skilled labor that is required, turret lathes, screw machines, and other types of semiautomatic and automatic lathes have been highly developed and are widely used in manufacturing.2 Numerical ControlOne of the most fundamental concepts in the area of advanced manufacturing technologies is numerical control (NC). Prior to the advent of NC, all machine tools ere manually operated and controlled. Among the many limitations associated with manual control machine tools, perhaps none is more prominent than the limitation of operator skills. With manual control, the quality of the product is directly related to and limited to the skills of the operator. Numerical control represents the first major step away from human control of machine tools.Numerical control means the control of machine tools and other manufacturing systems through the use of prerecorded, written symbolic instructions. Rather than operating a machine tool, an NC technician writes a program that issues operational instructions to the machine tool. For a machine tool to be numerically controlled, it must be interfaced with a device for accepting and decoding the programmed instructions, known as a reader.Numerical control was developed to overcome the limitation of human operators, and it has done so. Numerical control machines are more accurate than manually operated machines, they can produce parts more uniformly, they are faster, and the long-run tooling costs are lower. The development of NC led to the development of several other innovations in manufacturing technology:Electrical discharge machining,Laser cutting,Electron beam welding.Numerical control has also made machine tools more versatile than their manually operated predecessors. An NC machine tool can automatically produce a wide of parts, each involving an assortment of widely varied and complex machining processes. Numerical control has allowed manufacturers to undertake the production of products that would not have been feasible from an economic perspective using manually controlled machine tolls and processes.Like so many advanced technologies, NC was born in the laboratories of the Massachusetts Institute of Technology. The concept of NC was developed in the early 1950s with funding provided by the U.S. Air Force. In its earliest stages, NC machines were able to made straight cuts efficiently and effectively.However, curved paths were a problem because the machine tool had to be programmed to undertake a series of horizontal and vertical steps to produce a curve. The shorter the straight lines making up the steps, the smoother is the curve, Each line segment in the steps had to be calculated.This problem led to the development in 1959 of the Automatically Programmed Tools (APT) language. This is a special programming language for NC that uses statements similar to English language to define the part geometry, describe the cutting tool configuration, and specify the necessary motions. The development of the APT language was a major step forward in the fur ther development from those used today. The machines had hardwired logic circuits. The instructional programs were written on punchedpaper, which was later to be replaced by magnetic plastic tape. A tape reader was used to interpret the instructions written on the tape for the machine. Together, all of this represented a giant step forward in the control of machine tools. However, there were a number of problems with NC at this point in its development.A major problem was the fragility of the punched paper tape medium. It was common for the paper tape containing the programmed instructions to break or tear during a machining process. This problem was exacerbated by the fact that each successive time a part was produced on a machine tool, the paper tape carrying the programmed instructions had to be rerun through the reader. If it was necessary to produce 100 copies of a given part, it was also necessary to run the paper tape through the reader 100 separate tines. Fragile paper tapes simply could not withstand the rigors of a shop floor environment and this kind of repeated use.This led to the development of a special magnetic plastic tape. Whereas the paper carried the programmed instructions as a series of holes punched in the tape, the plastic tape carried the instructions as a series of magnetic dots. The plastic tape was much stronger than the paper tape, which solved the problem of frequent tearing and breakage. However, it still left two other problems.The most important of these was that it was difficult or impossible to change the instructions entered on the tape. To made even the most minor adjustments in a program of instructions, it was necessary to interrupt machining operations and make a new tape. It was also still necessary to run the tape through the reader as many times as there were parts to be produced. Fortunately, computer technology became a reality and soon solved the problems of NC associated with punched paper and plastic tape.The development of a concept known as direct numerical control (DNC) solved the paper and plastic tape problems associated with numerical control by simply eliminating tape as the medium for carrying the programmed instructions. In direct numerical control, machine tools are tied, via a data transmission link, to a host computer. Programs for operating the machine tools are stored in the host computer and fed to the machine tool an needed via the data transmission linkage. Direct numerical control represented a major step forward over punched tape and plastic tape. However, it is subject to the same limitations as all technologies that depend on a host computer. When the host computer goes down, the machine tools also experience downtime. This problem led to the development of computer numerical control.3 TurningThe engine lathe, one of the oldest metal removal machines, has a number of useful and highly desirable attributes. Today these lathes are used primarily in small shops where smaller quantities rather than large production runs are encountered.The engine lathe has been replaced in today’s production shops by a wide variety of automatic lathes such as automatic of single-point tooling for maximum metal removal, and the use of form tools for finish on a par with the fastest processing equipment on the scene today.Tolerances for the engine lathe depend primarily on the skill of the operator. The design engineer must be careful in using tolerances of an experimental part that has been produced on the engine lathe by a skilled operator. In redesigning an experimental part for production, economical tolerances should be used.Turret Lathes Production machining equipment must be evaluated now, more than ever before, this criterion for establishing the production qualification of a specific method, the turret lathe merits a high rating.In designing for low quantities such as 100 or 200 parts, it is most economical to use the turret lathe. In achieving the optimum tolerances possible on the turrets lathe, the designer should strive for a minimum of operations.Automatic Screw Machines Generally, automatic screw machines fall into several categories; single-spindle automatics, multiple-spindle automatics and automatic chucking machines. Originally designed for rapid, automatic production of screws and similar threaded parts, the automatic screw machine has long since exceeded the confines of this narrow field, and today plays a vital role in the mass production of a variety of precision parts. Quantities play an important part in the economy of the parts machined on the automatic screw machine. Quantities less than on the automatic screw machine. The cost of the parts machined can be reduced if the minimum economical lot size is calculated and the proper machine is selected for these quantities.Automatic Tracer Lathes Since surface roughness depends greatly on material turned, tooling , and feeds and speeds employed, minimum tolerances that can be held on automatic tracer lathes are not necessarily the most economical tolerances.In some cases, tolerances of 0.05mm are held in continuous production using but one cut . groove width can be held to 0.125mm on some parts. Bores and single-point finishes can be held to 0.0125mm. On high-production runs where maximum output is desirable, a minimum tolerance of 0.125mm is economical on both diameter and length of turn.车床车床主要是为了进行车外圆、车端面和镗孔等项工作而设计的机床。
数控车床主轴部件机械外文文献翻译、中英文翻译、外文翻译
数控车床主轴部件机械外文文献翻译、中英文翻译、外文翻译中国地质大学长城学院本科毕业设计外文资料翻译系别：工程技术系专业：机械设计制造及其自动化姓名：王泽民学号： 052116362015年4月30日外文原文翻译数控车床主轴部件车床是主要用于生成旋转表面和平整边缘的机床。
根据它们的使用目的、结构、能同时被安装刀具的数量和自动化的程度，车床—更确切地说是车床类的机床，可以被分成以下几类：(1)普通车床(2)万能车床(3)转塔车床(4)立式车床(5)自动车床(6)特殊车床虽然车床类的机床多种多样，但它们在结构和操作原理上具有共同特性。
这些特性可以通过普通车床这一最常用的代表性类型来最好地说明。
下面是关于图11.1所示普通车床的主要部分的描述。
车床床身：车床床身是包含了在两个垂直支柱上水平横梁的主骨架。
为减振它一般由灰铸铁或球墨铸铁铸造而成。
它上面有能让大拖板轻易纵向滑动的导轨。
车床床身的高度应适当以让技师容易而舒适地工作。
主轴箱：主轴箱固定在车床床身的左侧，它包括轴线平行于导轨的主轴。
主轴通过装在主轴箱内的齿轮箱驱动。
齿轮箱的功能是给主轴提供若干不同的速度(通常是6到18速)。
有些现代车床具有采用摩擦、电力或液压驱动的无级调速主轴箱。
主轴往往是中空的，即纵向有一通孔。
如果采取连续生产，棒料能通过此孔进给。
同时，此孔为锥形表面可以安装普通车床顶尖。
主轴外表面是螺纹可以安装卡盘、花盘或类似的装置。
尾架：尾架总成基本包括三部分，底座、尾架体和套筒轴。
底座是能在车床床身上沿导轨滑动的铸件，它有一定位装置能让整个尾架根据工件长度锁定在任何需要位置。
这通过使用手轮和螺杆来达到，与螺杆啮合的是一固接在套筒轴上的螺母。
套筒轴开口端的孔是锥形的，能安装车床顶尖或诸如麻花钻和镗杆之类的工具。
套筒轴通过定位装置能沿着它的移动路径被锁定在任何点。
大拖板：大拖板的主要功能是安装刀具和产生纵向和/或横向进给。
它实际上是一由车床床身V形导轨引导的、能在车床床身主轴箱和尾架之间滑动的H形滑块。
数控技术在机械制造中的有效应用外文文献翻译、中英文翻译、外文翻译
本科生毕业设计 (论文)
外文翻译
原文标题The Effective Use in the Process of Numerical
Technology in Mechanical Manufacturing
译文标题数控技术在机械制造中的有效应用
作者所在系别机电工程学院
作者所在专业车辆工程
作者所在班级B13142
作者姓名郝立新
作者学号201322375
指导教师姓名赵秋芳
指导教师职称副教授
完成时间2017 年 2 月
北华航天工业学院教务处制
注：1. 指导教师对译文进行评阅时应注意以下几个方面：①翻译的外文文献与毕业设计（论文）的主题是否高度相关，并作为外文参考文献列入毕业设计（论文）的参考文献；②翻译的外文文献字数是否达到规定数量（3 000字以上）；③译文语言是否准确、通顺、具有参考价值。
2. 外文原文应以附件的方式置于译文之后。
数控车床主轴部件机械外文文献翻译、中英文翻译、外文翻译
中国地质大学长城学院本科毕业设计外文资料翻译系别：工程技术系专业：机械设计制造及其自动化姓名：王泽民学号： 052116362015年4月30日外文原文翻译数控车床主轴部件车床是主要用于生成旋转表面和平整边缘的机床。
根据它们的使用目的、结构、能同时被安装刀具的数量和自动化的程度，车床—更确切地说是车床类的机床，可以被分成以下几类：(1)普通车床(2)万能车床(3)转塔车床(4)立式车床(5)自动车床(6)特殊车床虽然车床类的机床多种多样，但它们在结构和操作原理上具有共同特性。
这些特性可以通过普通车床这一最常用的代表性类型来最好地说明。
下面是关于图11.1所示普通车床的主要部分的描述。
车床床身：车床床身是包含了在两个垂直支柱上水平横梁的主骨架。
为减振它一般由灰铸铁或球墨铸铁铸造而成。
它上面有能让大拖板轻易纵向滑动的导轨。
车床床身的高度应适当以让技师容易而舒适地工作。
主轴箱：主轴箱固定在车床床身的左侧，它包括轴线平行于导轨的主轴。
主轴通过装在主轴箱内的齿轮箱驱动。
齿轮箱的功能是给主轴提供若干不同的速度(通常是6到18速)。
有些现代车床具有采用摩擦、电力或液压驱动的无级调速主轴箱。
主轴往往是中空的，即纵向有一通孔。
如果采取连续生产，棒料能通过此孔进给。
同时，此孔为锥形表面可以安装普通车床顶尖。
主轴外表面是螺纹可以安装卡盘、花盘或类似的装置。
尾架：尾架总成基本包括三部分，底座、尾架体和套筒轴。
底座是能在车床床身上沿导轨滑动的铸件，它有一定位装置能让整个尾架根据工件长度锁定在任何需要位置。
这通过使用手轮和螺杆来达到，与螺杆啮合的是一固接在套筒轴上的螺母。
套筒轴开口端的孔是锥形的，能安装车床顶尖或诸如麻花钻和镗杆之类的工具。
套筒轴通过定位装置能沿着它的移动路径被锁定在任何点。
大拖板：大拖板的主要功能是安装刀具和产生纵向和/或横向进给。
它实际上是一由车床床身V形导轨引导的、能在车床床身主轴箱和尾架之间滑动的H形滑块。
机械类数控外文翻译外文文献英文文献数控
机械类数控外文翻译外文文献英文文献数控IntroductionIn recent years, with the rapid development of science and technology, the traditional manufacturing industry has been facing tremendous challenges. In this context, computerized numerical control (CNC) technology has emerged as a revolutionary methodology that greatly improves the efficiency and accuracy of manufacturing processes. Specifically, CNC technology is a type of automated control system that uses a set of computer instructions to direct the movement and operation of machinery in the manufacturing process. In this regard, this paper will provide a comprehensive overview of CNC technology, including its history, applications, advantages, and challenges.History of CNC TechnologyCNC technology has a history that can be traced back to the 1940s. At that time, the aviation industry in the United States was seeking a way to improve the efficiency and accuracy of manufacturing. Therefore, the US Air Force and the Massachusetts Institute of Technology (MIT) cooperated to develop a system that automatically controlled the movement ofaircraft components during the manufacturing process. This system was called the numerical control (NC) system.In the mid-1950s, John Parsons, a researcher at the Massachusetts Institute of Technology, invented the first NC machine tool. The machine used punched tape to control the movement of the cutting tool. During the 1960s, digital computer technology became more advanced, which paved the way for the development of CNC machines. By 1970, CNC machines had become a mature and widely used technology in the manufacturing industry.Applications of CNC TechnologyCNC technology has a wide range of applications in the manufacturing industry. For example, CNC machines can be used to produce a variety of products, including automobile parts, aircraft components, medical equipment, and consumer goods. CNC technology is also used in many other industries, such as woodworking, metalworking, plastics, and textiles.CNC technology has revolutionized the manufacturing industry by improving the quality, precision, and consistency of products. In addition, CNC machines can work faster and often require less manual labor than traditional manufacturing methods. CNC technology also allows manufacturers to produce complex shapes and designs that would be difficult or impossible to produce using traditional manufacturing methods.Advantages of CNC TechnologyThere are several advantages of using CNC technology in manufacturing. First, CNC machines can produce parts with very high precision and accuracy, which is crucial in industries such as aerospace and medical equipment manufacturing. CNC machines can also work 24/7, which means that manufacturers can produce parts at any time of day or night without having to worry about workers becoming tired.Second, CNC machines are highly flexible and can be programmed to produce a wide range of products. This means that manufacturers can quickly switch between different products without having to buy new machines or invest in expensive retooling. This flexibility also allows manufacturers to respond quickly to changes in market demand.Third, CNC machines can greatly reduce the amount of waste generated during the manufacturing process. This is because CNC machines can accurately measure and cut materials, minimizing the amount of scrap that is created. In addition, CNC machines can be programmed to optimize the use of materials, further reducing waste.Challenges of CNC TechnologyDespite its many advantages, CNC technology also presents several challenges. First, CNC machines can be expensive to purchase and maintain, which can be a barrier for smallmanufacturers. In addition, CNC machines require skilled operators who can program and operate the machines. This means that manufacturers must invest in training their workers, which can also be costly.Second, CNC machines can sometimes be less efficient than traditional manufacturing methods for small production runs. This is because CNC machines require a certain amount of time to set up and program, which can be inefficient for small production runs. In addition, CNC machines require a certain amount of precision, which means that they may not be suitable for certain types of products, such as handmade crafts.Finally, CNC machines also present some ethical challenges. For example, some argue that CNC machines could lead to job loss in the manufacturing industry, as the machines can perform tasks that were previously done by workers. In addition, CNC machines could lead to a reduction in the quality of products, as manufacturers may be more focused on speed and efficiency rather than quality.ConclusionCNC technology has revolutionized the manufacturing industry by improving the quality, precision, and consistency of products. CNC machines are highly flexible and can be programmed to produce a wide range of products. In addition, CNC machines can greatly reduce the amount of waste generated during the manufacturing process. However, CNC technology alsopresents several challenges, including high cost, the need for skilled operators, efficiency issues for small production runs, and ethical concerns. Overall, CNC technology is a powerful tool for manufacturers, but it is important for manufacturers to carefully consider the costs and benefits of using this technology.。
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英文原文On the NC latheCNC machine tool numerical control machine tools (Computer numerical control machine tools) abbreviation, is provided with a program control system of automatic machine tools. The logic control system can deal with the control code or other symbolic instruction specified program, and decoding the digital code, said information carrier, through the numerical control device input. After processing by CNC device control signals, control the machine movements, by drawing the shape and size requirements, will be automatically processed by the parts.Features: CNC machine tool operation and monitoring of all completed in the numerical control unit, it is the brain of CNC machine tools. Compared with the general machine tools, CNC machine tools has the following characteristics:● the processing object adaptability, adapt to the characteristics of mold products such as a single production, provide the appropriate processing method for die and mould manufacturing;● high machining accuracy, proce ssing with stable quality;● can coordinate linkage, processing complex shape parts;● machining parts change, only need to change the program, can save the preparation time of production;● the machine itself high precision, rigidity, can choose the amoun t of processing good, high productivity (3~5 times as common machine);The machine is a high degree of automation, reducing labor intensity;● conducive to the production management modernization. The use of CNC machine tools and the standard code of digital information processing, information transmission, the use of computer control method, has laid the foundation for the integration of computer aided design, manufacturing and management;● on the operators of higher quality, higher demands for the repair of the technical staff;● high reliability.Composition: CNC machine tools in general by the input medium, man-machine interactive equipment, CNC equipment, feed servo drive system, spindle servo drive system, the auxiliary control device, feedback apparatus and adaptive control device etc.. [4] in NC machining, NC milling processing is the most complex, need to solve most problems. NC programming of NC line in addition to CNC milling, cutting, CNC EDM, CNC lathe, CNC grinding, each with its owncharacteristics, servo system is the role of the motion signal is converted into the machine moving parts from the numerical control device of pulse. Concrete has the following parts: the structure of CNC machine tools.Driver: he is driving parts of CNC machine tools, actuator, including spindle drive unit, feeding unit, spindle motor and feed motor. He through the electric or electro-hydraulic servo system to realize the spindle and feed drive under the control of numerical control device. When several feed linkage, can complete the positioning, processing line, plane curve and space curve.The main performance(1) the main dimensions.(2) the spindle system.(3) feed system.(4) tool system.(5) electrical. Including the main motor, servo motor specifications and power etc..(6) cooling system. Including the cooling capacity, cooling pump output.(7) dimensions. Expressed as length * width * height.Development trend of CNC lathe:High speed, precision, complex, intelligent and green is the general trend in the development of CNC machine tool technology, in recent years, made gratifying achievements in practicality and industrialization. Mainly in the:1 machine tool composite technology to further expand with the CNC machine tool technology, composite processing technology matures, including milling - car compound, car milling compound, car - boring - drill - gear cutting compound, composite grinding, forming, composite processing, precision and efficiency of machining is greatly improved. "One machine is a processing factory", "one card, complete processing" concept is being accepted by more people, the development of compound processing machine tool is the trend of diversified.Intelligent technology 2 CNC machine tools have a new breakthrough, in the performance of NC system has been reflected more. Such as: automatically adjust the interference anti-collision function, after the power of workpiece automatically exit safety power-off protection function, machining parts detection and automatic compensation function of learning, high precision machining parts intelligent parameter selection function, process automatic elimination of machine vibration functions into the practical stage, intelligent upgrade the function of machine and quality.The 3 robots enable flexible combination of flexible combination of higher efficiency of robot and the host are widely used, make flexible line more flexible, extending the function, flexible line shorten further, more efficient. Robot and machining center, milling composite machine, grinder, gear processing machine tool, tool grinding machine, electric machine, sawing machine, punching machine, laser cutting machine, water cutting machine etc. various forms of flexible unit and flexible production line has already begun the application.4 precision machining technology has the machining precision of CNC metal cutting machine tools from the yarn in the original (0.01mm) up to micron level (0.001mm), some varieties has reached about 0.05 μ M. Micro cutting and grinding machining of ul tra precision CNC machine tools, precision can reach about 0.05 μ m, shape precision can reach about 0.01 μ M. Special processing precision by using optical, electrical, chemical, energy can reach nanometer level (0.001 μ m). By optimizing the design of ma chine tool structure, machine tool parts of ultra precision machining and precision assembly, using high precision closed loop control and temperature, vibration and other dynamic error compensation technology, improve the geometric accuracy of machine tool processing, reduce the shape of error, surface roughness, and into the submicron, nano super finishing tiThe 5 functional component to improve the performance of functional components are at a high speed, high precision, high power and intelligent direction, and obtain the mature application. A full digital AC servo motor and drive device, high technology content of the electric spindle, linear motor, torque motor, linear motion components with high performance, application of high precision spindle unit and other function parts, greatly improving the technical level of CNC machine tools.The feed drive system of CNC lathe:Effect of feed drive system,The feed drive system of CNC machine tools will be received pulse command issued by the numerical control system, and the amplification and conversion machine movements carry the expected movement.Two, the feeding transmission system requirementsIn order to guarantee the machining accuracy of NC machine tool is high, the feed drive system of transmission accuracy, sensitivity high (fast response), stable work, high stiffness and friction and inertia small, service life, and can remove the transmission gap.Category three, feed drive system1, stepping motor servo systemGenerally used for NC machine tools.2, DC servo motor servo systemPower is stable, but because of the brush, the wear resulting in use need to change. Generally used for middle-grade CNC machine tools.3, AC servo motor servo systemThe application is extremely widespread, mainly used in high-end CNC machine tools.4, the linear motor servo systemNo intermediate transmission chain, high precision, the feed speed, no length limit; but the poor heat dissipation, protection requirements are particularly high, mainly used for high-speed machine.Driving component four, feed system1, the ball screw nut pairNC machining, the rotary motion into linear motion, so the use of screw nut transmission mechanism. NC machine tools are commonly used on the ball screw, as shown in Figure 1-25, it can be a sliding friction into rolling friction, meet the basic requirements of the feed system to reduce friction. The transmission side of high efficiency, small friction, and can eliminate the gap, no reverse air travel; but the manufacturing cost is high, can not lock, size is not too big, generally used for linear feed in small CNC machine tool.2, rotary tableIn order to expand the scope of the process of NC machine tools, CNC machine tools in addition to make linear feed along the X, Y, Z three coordinate axes, often also need a circumferential feed movement around Y or Z axis. Circular feed motion of CNC machine tools in general by the rotary table to realize, for machining center, rotary table has become an indispensable part of.Rotary table of commonly used CNC machine tools in the indexing table and NC rotary table.(1) indexing tableIndexing table can only finish dividing movement, not circular feed, it is in accordance with the instructions in the NC system, when indexing will work together with the workpiece rotation angle. When indexing can also use manual indexing. Provisions of indexing table is generally only rotary angle (such as 90, 60 and 45 degree).(2) NC rotary tableNC rotary table appearance similar to the indexing table, but the internal structure and function is not the same. The main function of the NC rotary table is based on the numerical control devicesends command pulse signal, complete circumferential feed movement, various arc processing and surface processing, it can also be graduation work.3, guideRail is an important part of feed drive system, is one of the basic elements of the structure of machine tool, rigidity, precision and accuracy of NC machine tool which determines to a large extent retention. At present, guide the NC machine tool are sliding rail, rolling guideway and hydrostatic guideway.(1) sliding guideSliding guide rail has the advantages of simple structure, easy manufacture, good stiffness, vibration resistance and high performance, widely used in CNC machine tools, the use of most metal plastic form, known as the plastic guide rail, as shown in figure 1-26.On characteristics of the plastic sliding guide: friction characteristic is good, good wear resistance, stable movement, good manufacturability, low speed.(2) rolling guideRolling guide is placed in the rail surface between the ball, roller or needle roller, roller, the rolling friction instead of sliding surface of the guide rail between wipe.Rolling guide rail and the sliding rail, high sensitivity, small friction coefficient, and the dynamic, static friction coefficient is very small, so the motion is uniform, especially in the low speed movement, the stick-slip phenomenon is not easy to occur; high positioning accuracy, repeatability positioning accuracy is up to 0.2 μ m; traction force is small, wear small, portable in movement; good precision, long service life. But the vibration of rolling guide, high requirements on protection, complicated structure, difficult manufacture, high cost.Automatic tool changer:One, the function of automatic tool changerAutomatic tool changing device can help save the auxiliary time of CNC machine tools, and meet in an installation completed procedure, step processing requirements.Two, on the requirement of automatic tool changerNumerical control machine tool for automatic tool changer requirement is: tool change quickly, time is short, high repetitive positioning accuracy, tool storage capacity is sufficient, small occupation space, stable and reliable work.Three, change the knife form1, rotary cutter replacementIts structure is similar to the ordinary lathe turret saddle, according to the processing of different objects can be designed into square or six angle form, consists of the NC system sends out the instruction to the rotary cutter.2, the replacement of the spindle head tool changeThe spindle head pre-loaded required tools, in order to machining position, the main motor is switched on, drives the cutter to rotate. The advantage of this method is that eliminates the need for automatic clamping, cutting tool, clamping and cutting tool moving and a series of complex operation, reduce tool change time, improveThe ATC reliability.3, the use of changing toolThe processing required tools are respectively arranged in the standard tool, adjust the size of the machine after certain way add to the knife, the exchange device from the knife and the spindle take knife switch.Four, the tool switching deviceAutomatic tool change device, device for knife library and the main shaft transmission and handling tool for tool exchange device. Tool exchange often have two kinds: mechanical hand tool exchange and by relative motion of knife and machine tool spindle exchange tool (knife to spindle forThe knife or the spindle motion to the knife knife tool change position), the mechanical hand tool change is most common.Five, the knifeThe knife is one of the most important parts in automatic tool changer, have great influence on the overall design of NC machine tool and its capacity, layout and structure.1, the capacity of the tool storageA number of knife inventory cutters, generally depending on the processing requirements. The capacity of small knife, can not meet the processing needs; capacity is too large, will make the knife database size, covers an area of large, tool selection process for a long time, and the knife library utilization rate is low, the structure is too complex, causing great waste. 2, the knife typeGenerally, the chain disc and drum type knife several.Disc cutter tool was circular arrangement, low utilization of space, size is not large but simple structure.Chain magazine compact structure, large capacity, link shape can also be random bed made of various forms and flexible layout, but also will change the cutter location prominent for tool change, widely used.Drum type or lattice type knife, covers an area of small, compact structure, large capacity, but cutter selection, tool movements are complicated, for centralized knife system for FMS.3, tool selectionOften order tool selection and random selection tool two.The order of tool selection is before processing, the processing required tools to process sequence of insert knife knife, order not wrong, processing adjust knife in order. The work piece changes, the need to reset the tool sequence, the operation is simple, and the processing tool with a workpiece can not be repeated use.A knife is the cutting tool has its own code, optional and can be repeatedly used in processing, also do not put in the fixed knife, knife, the knife is convenient.Technology file is the guiding file workers during processing, process scheme is reasonable, not only affect the efficiency of NC machining, and will directly affect the machining quality. Therefore, before NC programming, NC machining process follows the process of certain principles and combined with the characteristics of CNC lathe seriously and develop in detail the good parts.In the CNC lathe processing parts, should according to the principle of dividing process concentrated, in a fixture as far as possible to complete the most or even all of the surface processing. Part positioning, according to the structure of different shapes, usually cylindrical, face or end clamping, and strive to design basis, process reference and programming the unification datum.The main contents are: analysis of NC machining technology of part drawings, clear processing content; determination method, workpiece on lathe the surface processing sequence and tool feed line and cutting tools, fixtures and cutting the amount of choice.Analysis, part drawing processIn the machining process planning of parts, first of all to carry on in-depth analysis to the processing object. For NC turning process should consider the following aspects:1 reading part drawing, analysis of geometric conditions of part contourIn turning process of manual programming, to calculate each node coordinates; in automatic programming, to define the components outline all geometric elements. Therefore, in the analysis of parts should pay attention to:Parts of the map is missing a dimension, the geometric conditions are not sufficient to constitute the part outline, influence;Map location map parts of the ambiguity or dimension is not clear, so that the program can't start;The part drawing geometry given is not reasonable, resulting in mathematical difficulties.The part drawing dimensioning methods should adapt to the characteristics of CNC lathe processing, should size or directly given coordinate dimension with the same standard.2 dimensional accuracy requirementsAnalysis of the pattern of parts size precision requirements, to determine whether achieve the turning process, and determine the process method to control the dimension precision.In the analysis process, but also can convert some dimensions such as size, incremental and absolute size and dimension chain calculation. In the use of NC lathe turning parts, average value of components often required size and maximum and minimum limit of size size as the basis of programming.3 shape and position accuracy requirementsPattern of parts tolerance of shape and location given is important foundation to ensure the parts precision. When machining parts, to determine the location reference and measurement reference according to the requirements, can also carry out some technical processing according to the special needs of CNC lathe parts, in order to control effectively the shape and position accuracy.4 requirements of surface roughnessSurface roughness is an important requirement of micro precision parts of the surface, but also the reasonable selection of NC lathe, cutting tools and cutting the amount determined on the basis of.5 material and heat treatment requirementsThe part drawing on material and heat treatment given requirements, is the choice of cutter, CNC lathe, cutting the amount determined on the basis of model.Determination of two and fixture, clamping scheme selectionDivision 1.(1) according to the tool used by the process division can improve machining efficiency.(2) can keep the NC lathe machining according to the rough, finishing process division adopted this approach accuracy.The 2 part is determined and the fixture clamping scheme selectionThe CNC lathe parts mounting method is the same with the ordinary lathe, universal fixture should try to choose the existing clamping, and attention should be paid to reduce clamping times, as far as possible in one clamping parts can put all to processing surface processing. Datum location should be coincident with the design reference, in order to reduce the positioning error effect on the dimensional accuracy.CNC lathe with chuck with three jaws to clamp workpiece; shaft parts can also be used to support the tailstock center. Due to the NC lathe spindle speed is very high, for the convenience of the workpiece clamping, the use of hydraulic high-speed power chuck, because it is in the production plant has passed the strict balanced, with a high speed (the speed limit is 4000 ~ 6000rpm), high clamping force (the maximum force is 2000 ~ 8000N), high precision, convenient adjusting claw, a through hole long service life, etc.. By adjusting the pressure of oil cylinder, which can change the clamping force, the special needs of holding various thin-walled workpiece deformation and easy to meet.Deformation of slender shaft processing to reduce stress, improve the machining accuracy, as well as in processing the shaft with hole workpiece inner hole, the hydraulic automatic centering central frame, the centering precision can reach 0.03 mm.Three, determine the processing order and feed routeDetermination of 1 processing sequenceIn the process of NC machine tool, as the processing object is complicated, especially the shape and position of the myriads of changes curve, with the influence of different materials, different from that of the bulk and other factors, in the formulation of the processing sequence of specific parts, should make a concrete analysis and distinction, flexible processing. Only in this way, can the processing order of the rational, so as to achieve excellent quality, high efficiency and low cost objective.(1) the coarse to fineIn order to improve production efficiency and ensure the precision parts processing quality, in the cutting process, should arrange the roughing process, in a relatively short period of time, the finishing before machining allowance amount of removed, at the same time as much as possible to meet the precision machining allowance uniformity requirements.When the roughing process arrangement is finished, and then arrange the semi-finish machining and finish machining for the knife after the. Among them, arrange the semi-finishing aims, when after the rough machining allowance of uniformity can not meet the precision requirement, canarrange the semi-finish machining as a transitional process, in order to make the finishing allowance is small and uniform.In the arrangement of a knife or blade finish machining process of the part, the final contour should be the last knife and continuous processing. At this time, the cutting tool and cutter location to consider appropriate, try not to arrange the cut and cut out or tool change and pause in a continuous contour, so as to avoid sudden changes of cutting force caused by elastic deformation, resulting in smooth connection defects, surface scratch shape mutation or retention tool mark profile.(2) to nearly far after processing, reduce air travel timeHere said the far and near, is according to the processing site relative to the size of the knife point distance. In general, especially in the rough, usually arranged from near the site of the first processing tool, tool bit far from site after processing, in order to shorten tool moving distance, reduce air travel time. For turning, the first after the far past helps maintain the rough orsemi-finished parts of the rigid, improve the cutting condition.(3) and crossOn both the inner surface (inner type cavity), and outer surface of machined parts, the processing sequence arrangement, should be done before and after surface rough machining, inner and outer surface finishing. Must not be parts of a portion of the surface (the inner or outer surface) after machining, processing and other surface (inner or outer surface).(4) surface of first principlesSurface is used as a fine benchmark priority should be processed, because the surface of locating datum is more precise, clamping error is smaller. For example, shaft parts processing, always first machining center hole, and then to the center hole for precision machining surface and surface.The principle is not immutable and frozen, for some special cases, you need to take a flexible scheme.Determination of processing feed line 2The feed line is the tool relative to the workpiece in the whole movement process, it not only includes the steps of content, but also reflect the step sequence. One of the feed line is the basis of programming.Determine the processing route must keep the size precision and surface quality of machining parts, then consider the numerical calculation is simple, knife route as short as possible, higher efficiency. Because of the feed line finishing is basically along the contour sequence, therefore the determination of feed line focus is to determine the feed line rough machining and air travel. The following will analyze:(1) the relationship between processing route and machining allowanceIn the CNC lathe is not to popularize the use of conditions, the general should be a roughcast margin too much, especially with forging, casting hard layer cushion placed in ordinary lathe. If must use NC lathe machining, should pay attention to the flexible program. The first cutting processing must arrange some subroutine to margin too much site.(2) the tool cut, cut outThe processing of CNC machine tools, to arrange the tool cut, cut out the route, the tangent direction to make the tool along the outline of the cut, cut out.(3) to determine the shortest route for emptyDetermine the shortest tool path, in addition to rely on a lot of practical experience, should be good at analysis, if necessary, supplemented by some simple calculations.(4) determine the cutting feed shortestCutting feed route is short, can effectively improve the production efficiency, reduce the tool wear. In the cutting feed route arrangement the rough or semi-finished, it shall also take into account to be rigid and processing parts processing technology requirements, do not care for this and lose that.Four, to determine the cutting parametersCNC programming, the programmer must determine the cutting parameters of each process, and instructions in the form of written procedures. Cutting parameters including spindle speed, depth of cut and feed speed. For the different processing methods, selection of cutting parameters for different needs. Principle of selection of cutting parameters is: to ensure the accuracy and surface roughness of the parts processing, give full play to the tool cutting performance, guarantee a reasonable tool life and give full play to the performance of the machine tool, to maximize the productivity, reduce the cost of.To determine the 1 spindle speed(1) determine the spindle speed of light carSpindle speed should be based on the allowable cutting speed and workpiece diameter selection, the calculation formula is as followsN=1000v/ (d)Type V -- the cutting speed (M / min), determined by the tool life.N -- the spindle speed (R / min);D -- or the diameter of cutter and workpiece diameter (mm).Spindle speed calculation n finally depends on the machine specifications selecting machine or close to the speed of.(2) the car threaded spindle speedIn thread cutting, the lathe spindle speed will be thread pitch (or lead) factors affecting size, driving motor movements frequency characteristics and thread interpolation operation speed, the different NC systems, recommended the spindle speed range of different options. Spindle speed as most ordinary lathe CNC system recommended threading:N ≤ 1200/p-KType P -- pitch or lead the thread (mm);K -- the insurance factor, usually taken as 80;N -- the spindle speed, rpm.To determine the 2 feed speedThe feed velocity is an important parameter in the CNC machine tool cutting, mainly according to the machining accuracy and surface roughness value selection of parts and tool, workpiece material properties. The maximum speed limit by the performance of machine tool stiffness and feed system.To determine the feed speed is the principle:(1) when the workpiece quality requirements can be guaranteed, in order to improve the production efficiency, can choose the higher feed rate. 100 ~ 200mm / min range selection.(2) in cutting, machining deep hole or processing of high-speed steel cutting tool, should choose a lower feeding rate, generally in the 20 ~ 50mm / min range selection.(3) when processing high precision and surface roughness values is small, the feed rate should be smaller, the range of 20~50mm/min selection.(4) the tool to air travel, especially to zero distance, can be set to the highest feed speed setting of the machine tool CNC system.To determine the depth of the 3The cutting depth was decided according to machine tool, workpiece and cutting tool rigidity, stiffness in the permit conditions, should as far as possible back an amount equal to the machining allowance of the workpiece, thus reducing the feeding times, improve production efficiency. 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