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第1页共2页机械加工工艺卡片产品型号零件图号产品名称SSCK20A零件名称主轴序号工序工 序 内 容车间设备工 艺 装 备工等工时单件备注夹具刃具量具辅具0备料10精锻立式精锻机20热处理正火30锯头40铣端面专用机床50粗车车各外圆面卧式车床60热处理调质220240HBS70车大端面卧式车床80粗车仿形车小端各部仿形车床90钻钻打断各孔摇臂钻床第2页共2页机械加工工艺卡片产品型号零件图号产品名称SSCK20A零件名称主轴序号工序工 序 内 容车间设备工 艺 装 备工等工时单件备注夹具刃具量具辅具100热处理高频感应加热淬火110数车精车各外圆并车槽数控车床120粗磨粗磨个外圆万能外圆磨床130精铣铣键槽铣床140精车加工三段螺纹卧式车床150粗精磨粗精磨各外圆万能外圆磨床第1页共6页机械加工工艺卡片产品型号零件图号产品名称SSCK20A零件名称主轴箱体序号工序工 序 内 容车间设备工 艺 装 备工等工时单件备注夹具刃具量具辅具0铸造正火10划线照顾毛坯各部划立车加工线20立车车4650.2两面,各面均留量3mm30划线划镗序加工线40卧镗镗铣A面，B面留量3mm以A面为基面,B面为导向粗镗150(-0.008,+0.002)140(-0.007,+0.003)各孔留量半径3mm过孔留量半径3mm050二次正火060划线划车序加工线第2页共6页机械加工工艺卡片产品型号零件图号产品名称SSCK20A零件名称主轴箱序号工序工 序 内 容车间设备工 艺 装 备工等工时单件备注夹具刃具量具辅具070立车车4650.2尺寸两面,至4650.1mm,两面平行0.1mm080划线划刨、镗序加工线090卧镗1）镗铣A面、B面各留量0.50.6mm铣30尺寸下面达图铣5尺寸空刀至尺寸2）按线铣右视图上部两处135度斜面达图铣：1500.2尺寸上面留量0.5mm钻：2M12底孔 X8(起吊孔)钻：2M12底孔（右上图局部剖）按线钻攻：左、右视图4M16（装配起吊孔）3）以A面为基面、 B面导向粗镗150(-0.008,+0.002)140(-0.007,+0.003)各孔留量半径11.2 mm过孔留量半径 11.2 mm第3页共6页机械加工工艺卡片产品型号零件图号产品名称SSCK20A零件名称主轴箱序号工序工 序 内 容车间设备工 艺 装 备工等工时单件备注夹具刃具量具辅具100数镗以465尺寸左面为基面； 工件压在工作台一角位置， 找正A面在0.1以内， 精铣A、B面（B面精加工用30立铣刀侧刃加工，不许有接刀痕，吃刀深度0.2mm)粗糙度达Ra3.2,平面度达0.05mm110卧镗 1）以465尺寸左面为基面；工件压在工作台一角位置找正A面在0.1以内，铣3X2空刀（根据刀具情况可加工至5X3）2）工作太转90度，包拯350尺寸，铣350尺寸左面达 Ra6.3。3）铣320尺寸两面：左面粗糙度达Ra3.2。4）铣380尺寸右6.3 面。5）钻4M6、2M8底孔。120卧镗以A面为基面，B面导向，上等高垫铁、位置公差军达图纸要求第4页共6页机械加工工艺卡片产品型号零件图号产品名称SSCK20A零件名称 主轴箱序号工序工 序 内 容车间设备工 艺 装 备工等工时单件备注夹具刃具量具辅具半精镗：150(-0.008,+0.002)140(-0.007,+0.003)、141.5孔留量，半径0.50.6mm。半精划：底面留量0.2mm精铣：280范围内，240范围内达Ra1.64650.2至465（+0.2，+0.3）130卧镗1、以465尺寸左面为基面，找正A面。在0.05以内实测140孔尺寸，按实际尺寸计算；精铣 1500.2尺寸上面。要求上面与C、D平行0.03mm。钻4M10底孔2、保证250.2，80尺寸自划线，钻划622X36140装配钳刮研A、B面。25MMX25MM范围内不少于8个点。B A达0.02MM150数镗以A面为基面、B面导向、第5页共6页机械加工工艺卡片产品型号零件图号产品名称SSCK20A零件名称主轴箱序号工序工 序 内 容车间设备工 艺 装 备工等工时单件备注夹具刃具量具辅具保证B面与主轴孔平行0.02上等高垫铁，300（0，+0.1）至300（0，+0.05）。500.1尺寸达500.05mm。保证深度尺寸115（-0.2，-0.1）。精镗141.5过孔至尺寸，精镗：140、150孔。孔径公差按轴承尺寸配镗；160卧镗1）精划Ra1.6底面。精铣：280、240（检查范围）。2）引窝：左视：6M8。 右视：6M10。在右视图125度左侧斜面打编号3） 三坐标检测：按图纸技术要求检测， 孔径用比较仪测量。170钻按窝钻攻：6M8、6M10180钳工各锐角倒钝、去刺第6页共6页机械加工工艺卡片产品型号零件图号产品名称SSCK20A零件名称主轴箱序号工序工 序 内 容车间设备工 艺 装 备工等工时单件备注夹具刃具量具辅具攻丝：4M6、4M12、2M84M10。190喷漆姓名： 任务下达日期： 年月日设计（论文）开始日期： 年 月 日设计（论文）完成日期： 年 月 日一、设计（论文）题目：SSCK20A数控车床主轴及主轴箱的数控加工及数控编程 二、专题题目： 数控五轴技术及数控编程 三、设计的目的和意义：随着社会的进步，制造业的发展越来越迅速，数控技术和数控装备是制造工业现代化的重要基础。这个基础是否牢固直接影响到一个国家的经济发展和综合国力，关系到一个国家的战略地位。因此，世界上各工业发达国家均采取重大措施来发展自己的数控技术及其产业。在我国，数控技术与装备的发展亦得到了高度重视，近年来取得了相当大的进步。数控机床发展很快，作为数控机床的重要部分，主轴箱的设计更新也越来越快。四、设计（论文）主要内容：（1）SSCK20A数控车床的主轴箱展开图（1张0号）、主轴零件图（1张1号）、箱体零件图（1张0号）、带轮零件图（1张2号）、前端盖零件图（1张2号）；（2）主轴及主轴箱的加工工艺规程；（3）主轴及主轴箱的部分加工工艺的数控程序；五、设计目标：主要完成对SSCK20A数控车床的主轴及主轴箱加工工艺规程设计以及部分加工工艺数控程序的编制。六、进度计划： 2007年3月13日至3月31日进行为期3周的生产实习；4月1日至4月10日完成对设计题目的资料收集与查询；4月11日至5月10日完成对设计图纸的绘制；5月11日至6月10日完成毕业设计说明书的编写；6月11日至6月20日最后的审稿及说明书和图纸的打印。 七、参考文献资料：许镇宇.机械零件.北京：高等教育出版社，1983；孔庆复.计算机辅助设计与制造.哈尔滨：哈尔滨工业大学出版社，1994；雷宏.机械工程基础.哈尔滨：黑龙江出版社 2002；王中发.实用机械设计.北京：北京理工大学出版社 1998； 唐宗军.机械制造基础.大连：机械工业出版社 1997；吴祖育，秦鹏飞.数控机床.上海：上海科学技术出版社 2003；许翔泰，刘艳芳. 数控加工编程实用技术.北京：机械工业出版社2000；吴明友.数控机床加工技术 东南大学出版社.江苏：2000；王宝成.现代数控机床.天津：天津科学技术出版社，2000；廖效果，朱启俅.数字控制机床.江西：华中科技大学出版社，2002；王卫兵.数控编程100例.机械工业出版社，2004；张树森.机械工程学.辽宁；东北大学出版社，2001；应云天.俄文翻译手册.北京：高等教育出版社，1999；金蓓.数控加工的编程技巧.航空精密制造技术.成都：2002，2；邓星钟. 机电传动控制(第三版). 武汉: 华中科技大学出版社, 2001； 指 导 教 师： 院（系）主管领导： 年 月 日附录2 外文翻译（外文部分）ADVANCED MACHINING PROCESSES As the hardware of an advanced technology becomes more complex, new and visionary approaches to the processing of materials into useful products come into common use. This has been the trend in machining processes in recent years. Advanced methods of machine control as well as completely different methods of shaping materials have permitted the mechanical designer to proceed in directions that would have been totally impossible only a few years ago. Parallel development in other technologies such as electronics and computers have made available to the machine tool designer methods and processes that can permit a machine tool to far exceed the capabilities of the most experienced machinist. In this section we will look at CNC machining using chip-making cutting tools. CNC controllers are used to drive and control a great variety of machines and mechanisms, Some examples would be routers in wood working; lasers, plasma-arc, flame cutting, and waterjets for cutting of steel plate; and controlling of robots in manufacturing and assembly. This section is only an overview and cannot take the place of a programming manual for a specific machine tool. Because of the tremendous growth in numbers and capability of computers ,changes in machine controls are rapidly and constantly taking place. The exciting part of this evolution in machine controls is that programming becomeseasier with each new advanced in this technology.Advantages of Numerical Control A manually operated machine tool may have the same physical characteristics as a CNC machine, such as size and horsepower. The principles of metal removal are the same. The big gain comes from the computer controlling the machining axes movements. CNC-controlled machine tools can be as simple as a 2-axis drilling machining center (Figure O-1). With a dual spindle machining center, the low RPM, high horsepower spindle gives high metal removal rates. The high RPM spindle allows the efficient use of high cutting speed tools such as diamonds and small diameter cutters (Figure O-2). The cutting tools that remove materials are standard tools such as milling cutters, drills, boring tools, or lathe tools depending on the type of machine used. Cutting speeds and feeds need to be correct as in any other machining operation. The greatest advantage in CNC machining comes from the unerring and rapid positioning movements possible. A CNC machine does dot stop at the end of a cut to plan its next move; it does not get fatigued; it is capable of uninterrupted machining error free, hour after hour. A machine tool is productive only while it is making chips. Since the chip-making process is controlled by the proper feeds and speeds, time savings can be achieved by faster rapid feed rates. Rapid feeds have increased from 60 to 200 to 400 and are now often approaching 1000 inches per minute (IPM). These high feed rates can pose a safety hazard to anyone within the working envelope of the machine tool. Complex contoured shapes were extremely difficult to product prior to CNC machining .CNC has made the machining of these shapes economically feasible. Design changes on a part are relatively easy to make by changing the program that directs the machine tool. A CNC machine produces parts with high dimensional accuracy and close tolerances without taking extra time or special precautions, CNC machines generally need less complex work-holding fixtures, which saves time by getting the parts machined sooner. Once a program is ready and production parts, each part will take exactly the same amount of time as the previous one. This repeatability allows for a very precise control of production costs. Another advantage of CNC machining is the elimination of large inventories; parts can be machined as needs .In conventional production often a great number of parts must be made at the same time to be cost effective. With CNC even one piece can be machined economically .In many instances, a CNC machine can perform in one setup the same operations that would require several conventional machines. With modern CNC machine tools a trained machinist can program and product even a single part economically .CNC machine tools are used in small and large machining facilities and range in size from tabletop models to huge machining centers. In a facility with many CNC tools, programming is usually done by CNC programmers away from the CNC tools. The machine control unit (MCU) on the machine is then used mostly for small program changes or corrections. Manufacturing with CNC tools usually requires three categories of persons. The first is the programmer, who is responsible for developing machine-ready code. The next person involved is the setup person, who loads the raw stork into the MCU, checks that the correct tools are loaded, and makes the first part. The third person is the machine and unloads the finished parts. In a small company, one person is expected to perform all three of these tasks. CNC controls are generally divided into two basic categories. One uses a ward address format with coded inputs such as G and M codes. The other users a conversational input; conversational input is also called user-friendly or prompted input. Later in this section examples of each of these programming formats in machining applications will be describes.CAM and CNC CAM systems have changed the job of the CNC programmer from one manually producing CNC code to one maximizing the output of CNC machines. Since CNC machine tools are made by a great number of manufacturers, many different CNC control units are in use. Control units from different manufacturers use a variety of program formats and codes. Many CNC code words are identical for different controllers, but a great number vary from one to another. To produce an identical part on CNC machine tools with different controllers such as one by FANCU, OKUMA or DYNAPATH, would require completely different CNC codes. Each manufacturer is constantly improving and updating its CNC controllers. These improvements often include additional code words plus changes in how the existing code works. A CAM systems allows the CNC programmer to concentrate on the creation of an efficient machining process, rather then relearning changed code formats. A CNC programmer looks at the print of a part and then plans the sequence of machining operations necessary to make it (Figure O-3). This plan includes everything, from the selection of possible CNC machine tools, to which tooling to use, to how the part is held while machining takes place. The CNC programmer has to have a thorough understanding of all the capacities and limitations of the CNC machine tools that a program is to be made for. Machine specifications such as horsepower, maximum spindle speeds, workpiece weight and size limitations, and tool changer capacity are just some of the considerations that affect programming. Another area of major importance to the programmer is the knowledge of machining processes. An example would be the selection of the surface finish requirement specified in the part print. The sequence of machining processes is critical to obtain acceptable results. Cutting tool limitations have to be considered and this requires knowledge of cutting tool materials, tool types, and application recommendations. A good programmer will spend a considerable amount of time in researching the rapidly growing volume of new and improved tools and tool materials. Often the tool that was on the cutting edge of technology just two years ago is now obsolete. Information on new tools can come from catalogs or tool manufacturers tooling engineers. Help in tool selection or optimum tool working conditions can also be obtained from tool manufacturer software. Examples would be Kennametals TOOLPRO, software designed to help select the best tool grade, speed, and feed rates for different work materials in turning application. Another very important feature of TOOLPRO is the display of the horsepower requirement for each machining selection. This allow the programmer to select a combination of cutting speed, feed rate, and depth of cut that equals the machines maximum horsepower for roughing cuts. For a finishing cut, the smallest diameter of the part being machined is selected and then the cutting speed varied until the RPM is equal to the maximum RPM of the machine. This helps in maximizing machining efficiency. Knowing the horsepower requirement for a cut is critical if more than one tool is cutting at the same time. Software for a machining center application would be Ingersoll Tool Companys Actual Chip Thickness, a program used to calculate the chip thickness in relation to feed-per-tooth for a milling cutter, especially during a shallow finishing cut. Ingersolls Rigidity Analysis software ealculates tool deflection for end mills as a function of tool stiffness and tool force. To this point we looked at some general qualifications that a programmer should possess. Now we examine how a CAM system works. Point Control Companys SmartCam system uses the following approach. First, the programmer makes a mental model of the part to be machined. This includes the kind of machining to be performed-turning or milling. Then the part print is studied to develop a machining sequence, roughing and finishing cuts, drilling, tapping, and boring operations. What work-holding device is to be used, a vise or fixture or clamps? After these considerations, computer input can be started. First comes the creation of a JOBPLAN. This JOBPLAN consists of entries such as inch or metric units, machine type, part ID, type of workpiece material, setup notes, and a description of the required tools. This line of information describes the tool by number, type, and size and includes the appropriate cutting speed and feed rate. After all the selected tools are entered, the file is saved. The second programming step is the making of the part. This represents a graphic modeling of the projected machining operation. After selecting a tool from the prepared JOBPLAN, parameters for the cutting operation are entered. For a drill, once the coordinate location of the hole and the depth are given, a circle appears on that spot. If the location is incorrect, the UNDO command erases this entry and allows you to give new values for this operation. When an end mill is being used, cutting movements (toolpath) are usually defined as lines and arcs. As a line is programmed, the toolpath is graphically displayed and errors can be corrected instantly. At any time during programming, the command SHOWPATH will show the actual toolpath for each of the programmed tools. The tools will be displayed in the sequence in which they will be used during actual machining. If the sequence of a tool movement needs to be changed, a few keystrokes will to that. Sometimes in CAM the programming sequence is different from the actual machining order. An example would be the machining of a pocket in a part. With CAM, the finished pocket outline is programmed first, then this outline is used to define the roughing cuts to machine the pocket. The roughing cuts are computer generated from inputs such as depth and width of cut and how much material to leave for the finish cut. Different roughing patterns can be tried out to allow the programmer to select the most efllcient one for the actual machining cuts. Since each tool is represented by a different color, it is easy to observe the toolpath made by each one. A CAM system lets the programmer view the graphics model from varying angles, such as a top, front, side, or isometric view. A toolpath that looks correct from a top view, may show from a front view that the depth of the cutting tool is incorrect. Changes can easily be made and seen immediately. When the toolpath and the sequence of operations are satisfactory, machine ready code has to be made. This is as easy as specifying the CNC machine that is to be used to machine the part. The code generator for that specific CNC machine during processing accesses four different files. The JOBPLAN file for the tool information and the GRAPHICE file for the toolpath and cutting sequence. It also uses the MACHINE DEFINE file which defines the CNC code words for that specific machine. This file also supplies data for maximum feed rates, RPM, toolchange times, and so on. The fourth file taking part in the code generating process is the TEMPLATE file. This file acts like a ruler that produces the CNC code with all of its parts in the right place and sequence. When the code generation is complete, a projected machining time is displayed. This time is calculated from values such as feed rates and distances traveled, noncutting movements at maximum feed rates between points, tool change times, and so on. The projected machining time can be revised by changing tooling to allow for higher metal removal rates or creating a more efficient toolpath. This display of total time required can also be used to estimate production costs. If more then one CNC machine tool is available to machine this part, making code and comparing the machining time may show that one machine is more efficient than the others.CAD/CAM Another method of creating toolpath is with the use of a Computer-aided Drafting (CAD) file. Most machine drawings are created using computers with the description and part geometry stored in the computer database. SmartCAM, though its CAM CONNECTION, will read a CAD file and transfer its geometry represents the part profile, holes, and so on. The programmer still needs to prepare a JOBPLAN with all the necessary tools, but instead of programming a profile line by line, now only a tool has to be assigned to an existing profile. Again, using the SHOWPATH function will display the toolpath for each tool and their sequence. Constant research and developments in CAD/CAM interaction will change how they work with each other. Some CAD and CAM programs, if loaded on the same computer, make it possible to switch between the two with a few keystrokes, designing and programming at the same time. The work area around the machine needs to be kept clean and clear of obstructions to prevent slipping or tripping. Machine surfaces should not be used as worktables. Use proper lifting methods to handle heavy workpieces, fixtures, or heavy cutting tools. Make measurements only when the spindle has come to a complete standstill. Chips should never be handled with bare hands. Before starting the machine make sure that the work-holding device and the workpiece are securely fastened. When changing cutting tools, protect the workpiece being machined from damage, and protect your hands from sharp cutting edges. Use only sharp cutting tools. Check that cutting tools are installed correctly and securely. Do not operate any machine controls unless you understand their function and what they will do.The Early Development Of Numerically Controlled Machine Tools The highly sophisticated CNC machine tools of today, in the vast and diverse range found throughout the field of manufacturing processing, started from very humble beginnings in a number of the major industrialized countries. Some of the earliest research and development work in this field was completed in USA and a mention will be made of the UKs contribution to this numerical control development. A major problem occurred just after the Second World War, in that progress in all areas of military and commercial development had been so rapid that the levels of automation and accuracy required by the modern industrialized world could not be attained from the lab our intensive machines in use at that time. The question was how to overcome the disadvantages of conventional plant and current manning levels. It is generally ackonwledged that the earliest work into numerical control was the study commissioned in 1947 by the US government. The studys conclusion was that the metal cutting industry throughout the entire country could not copy with the demands of the American Air Force, let alone the rest of industry! As a direct result of the survey, the US Air Force contracted the Persons Corporation to see if they could develop a flexible, dynamic, manufacturing system which would maximize productivity. The Massachusetts Institute of Technology (MIT) was sub-contracted into this research and development by the Parsons Corporation, during the period 1949-1951,and jointly they developed the first control system which could be adapted to a wide range of machine tools. The Cincinnati Machine Tool Company converted one of their standard 28 inch Hydro-Tel milling machines or a three-axis automatic milling made use of a servo-mechanism for the drive system on the axes. This machine made use of a servomechanism for the drive system on the axes, which controlled the table positioning, cross-slide and spindle head. The machine cab be classified as the first truly three axis continuous path machine tool and it was able to generate a required shape, or curve, by simultaneous slide way motions, if necessary. At about the same times as these American advances in machine tool control were taking Place, Alfred Herbert Limited in the United Kingdom had their first Mutinous path control system which became available in 1956.Over the next few years in both the USA and Europe, further development work occurred. These early numerical control developments were principally for the aerospace industry, where it was necessary to cut complex geometric shapes such as airframe components and turbine blades. In parallel with this development of sophisticated control systems for aerospace requirements, a point-to-point controller was developed for more general machining applications. These less sophisticated point-to-point machines were considerably cheaper than their more complex continuous path cousins and were used when only positional accuracy was necessary. As an example of point-to-point motion on a machine tool for drilling operations, the typical movement might be fast traverse of the work piece under the drills position-after drilling the hole, anther rapid move takes place to the next holes position-after retraction of the drill. Of course, the rapid motion of the slideways could be achieved by each axis in a sequential and independent manner, or simultaneously. If a separate control was utilisec for each axis, the former method of table travel was less essential to avoid any backlash in the system to obtain the required degree of positional accuracy and so it was necessary that the approach direction to the next point was always the same. The earliest examples of these cheaper point-to-point machines usually did not use recalculating ball screws; this meant that the motions would be sluggish, and sliderways would inevitably suffer from backlash, but more will be said about this topic later in the chapter. The early NC machines were, in the main, based upon a modified milling machine with this concept of control being utilized on turning, punching, grinding and a whole host of other machine tools later. Towards the end of the 1950s,hydrostatic slideways were often incorporated for machine tools of highly precision, which to sonic extent overcame the section problem associated with conventional slideway response, whiles averaging-out slideway inaccuracy brought about a much increased preasion in the machine tool and improved their control characteristics allows concept of the machining center was the product of this early work, as it allowed the machine to manufacture a range of components using a wide variety of machining processes at a single set-up, without transfer of workpieces to other variety machine tools. A machining center differed conceptually in its design from that of a milling machine, In that the cutting tools could be changed automatically by the transfer machanism, or selector, from the magazine to spindle, or vice versa.In this ductively and the automatic tool changing feature enabled the machining center to productively and efficiently machine a range of components, by replacing old tools for new, or reselecting the next cutter whilst the current machining process is in cycle. In the mid 1960s,a UK company, Molins, introduced their unique System 24 which was meant represent the ability of a system to machine for 24 hours per day. It could be thought of as a machining complex which allowed a series of NC single purpose machine tools to be linked by a computerized conveyor system. This conveyor allowed the work pieces to be palletized and then directed to as machine tool as necessary. This was an early, but admirable, attempt at a form of Flexible manufacturing System concept, but was unfortunately doomed to failure. Its principal weakness was that only a small proportion of component varieties could be machine at any instant and that even fewer work pieces required the same operations to be performed on them. These factors meant that the utilization level was low, coupled to the fact that the machine tools were expensive and allowed frequent production bottlenecks of work-in-progress to arise, which further slowed down the whole operation. The early to mid-1970s was a time of revolutionary in the area of machine tool controller development, when the term computerized numerical control (CNC) became a reality. This new breed of controllers gave a company the ability to change work piece geometries, together with programs, easily with the minimum of development and lead time, allowing it to be economically viable to machine small batches, or even one-off successfully. The dream of allowing a computerized numerical controller the flexibility and ease of program editing in a production environment became a reality when two ralated factors occurred.These were:the development of integrated circuits, which reduces electronics circuit size, giving better maintenance and allowing more standardization of desing; that general purpose computers were reduced in size coupled to the fact that their cost of production had fallen considerably. The multipie benefits of cheaper electorics with greater reliability have result in the CNC fitted to the machine tools today, with the power and sophistication progtessing considerably in the last few years, allowing an almost artificial intelligence(AI) to the latest systems. Over the years, the machine tools builders have produced a large diversity in the range of applications of CNC and just some of those development will be reviewed in Volume 。 With any capital cost item, such as a CNC machine tool, it is necessary for a company to undergo a feasibility study in order to ascertain whether the purchase of new plant is necessary and can be justified over a relatively short pay-back period. These thoughts and other circial decisions will be the subject of the next section which is concerned with the economic justification for CNC.附录3外文翻译（中文部分）机床实践随着先进科技的硬件变得复杂化，把原料加工成为有用产品的理想的、新的加工手段得到了普遍应用。这已经成为近几年机床加工的发展趋势。先进的机床控制方法和完全不同的材料成形方法还迫使机械设计人员进行前几年还完全没有进行的方向（研究）。其他科技如电子技术和计算机技术的并行发展，使机床设计者有办法让机床具有超过绝大多数经验丰富的机械师（在普通机床上）所具有的加工能力。在这个部分我们来看数控机床切削使用的工具。CNC控制器能被用来驱动和控制多种机床和机构。举几个例子，如刳刨机进行木料加工；激光、离子弧、火焰切削、喷水切削钢板；在制造和装配中机器人的控制等。本书的这个部分仅是一般介绍而不能作为专业机床的设计手册。由于计算机能力和容量的巨大增长，机床的控制技术很频繁地发生着变化。在机床控制发展中的精彩部分是在每个先进技术上的使用变得很容易了。NC的优势人工操作机床可能有和CNC机床一样的物理特性，例如马力和尺寸，其金属切削原理也是一样的。CNC最大的好处是通过计算机控制机床刀具的运动，CNC控制的机床可能简单得象2刀钻床或复杂得象5刀的加工中心（如图O-1）。两轴的加工机床，其特点是低转速、高马力轴有高进给率，高转速轴允许高效的高速切削刀具如钻石和小直径的刀具的使用（如图O-2）。它的切削刀具是标准的刀具如磨床的刀具、钻子、钻探工具或车刀，这些刀具依赖于所使用的机床型号。切削速度和进给量要象在其他操作机床中一样是正确的。CNC机床的最大优势来自无错的和快速的可能运动的控制。数控机床不会在一次加工完成后停下来计划下一次的运动，它不会疲劳，它是不中断的机床，机床只有在它切削的时候才有生产性。当切削过程被适当的进给量和切削速度控制时，时间的节约可以通过快速的进给率来完成。快速进给从60发展到200到400到现在已接近每分1000英寸了。这样高的进给率对在机床工作区的任何人构成了安全威胁。在CNC机床之前，复杂形状的加工是极困难的。CNC使这些形状的加工制造在经济上是可行的。零件的设计变化通过改变控制机床的程序而相对容易实现。CNC机床不需要额外的时间和特别的预防就可生产高精度的严格公差的零件。CNC使机床不需要复杂的夹具，这使零件很快被加工从而节约了时间。一旦程序准备好并加工零件，每个零件都将花与第一个一样的时间。这个一致性允许很精确地控制加工成本。数控机床的另一个优势是大量存货的减少，零件可以在需要时再被加工。在传统制造中，为了增加效率，通常一大批零件被同时加工。有了CNC即使一件也能够被经济地加工。在很多情况下，一个CNC机床完成了要建立几台相同传统机床才能做的操作。CAM和CNC CAM系统改变了CNC程序员的工作，即从手工编制CNC代码到CNC机床的输出最大值。自从手工CNC机床被一大批厂家生产以来，许多不同的CNC控制单元就被使用了。各个不同的厂家的控制单元使用各个不相同的程序与代码。许多CNC代码语句可被不同的控制器识别。但其间还有众多的区别。为了在有着不同控制器（如FAWC、OKUMA、或DYNAPATH）生产一个可互换的零件，将需要完全不同的CNC代码。每个制造商在不断地提高和更新其CNC控制。这些改进通常包括附加的代码语句在已有代码如何工作上的变化。CAM系统允许CNC程序员在高效的加工过程的建立上浓缩、精选、而不重新学习已改变的代码格式。一个CNC程序员看着一个零件的图纸，并且设计必要的机床操作来制造这个零件（如图O-3）。这个设计包括以下每个因素，从可能使用的CNC机床的选择，到机床的使用选择，再到加工时的零件装夹的选择。CNC程序员必须对这个即将写入程序的CNC机床的能力和局限有一个完全的了解。机床主参数如马力主轴马力、最大转速、工作台的重量、工具的尺寸限制、加工变化能力等只是值得考虑的影响程序的因素中的一些。对程序员要求的另一个最重要领域是制造过程的知识。举例如选择最佳的切削工具来完成零件图上所标的公差和表面光洁度。这个加工过程的程序是吹毛求疵地获得符合的结果。机床极限能力必须考虑全面，这就需要刀具材料，刀具类型，和其推荐应用的知识。一个优秀的程序员将花相当数量的时间来研究关于新的、改进的刀具和刀具材料的快速设计者发表的书籍。通常在切削方面使用两年前的技术的刀具现在就是落后的。新刀具的信息来自手册或刀具制造商的刀具之资料。刀具选择或最佳刀具工作条件的帮助同样可在刀具制造商的软件中获得。例如：Kennametals被设计来帮助不同的使用其车间的工厂选择最佳的机床；“TOOCPRO”的另一个很重要的特征是为每个机床选择马力需求等等这些就允许设计者选择一个结合了切削速度、进给率和切削深度等因素的机床。这就胜任于粗选中最佳马力的选择。对于光洁度的加工，零件在加工中最小进给量被选定，接着切削速度直到转速与机床的最佳转速相等时才不变。这就帮助最大提高了机床效率。如果不只一台机床在同时工作的话了解一台机床的功率需求是必要的。为加工中心使用的软件是ENGERSOLL CUTTING TOOL公司的ACTUAL CHIP THICKNESS。程序被用来计算磨床每次进的给量，特别是在微量的光洁度加工中。ENGERSOLL的“精密分析”软件作为机床刚度和机床力的功能来。在这一点上我们观察一些广泛的设计人员应掌握的规格。现在我们测试CAM系统怎样工作。点控公司（POINT CPNTROLL COMPANY）的SMARTCAM 系统使用接下来的手段：首先设计人员使用一个金属零件模型去加工。这包括的加工方式是-车或磨。接着这个零件图被研究来做成机床加工工序，粗加工或精加工、钻、冲、磨等操作。被使用的装夹夹具是虎钳，抓盘还是卡盘？这些考虑之后，计算机输出就可开始了。首先还是工艺卡