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精品文档数控技术数控技术，简称“数控”。英文：Numerical Control（NC）。是指用数字、文字和符号组成的数字指令来实现一台或多台机械设备动作控制的技术。它所控制的通常 是位置、角度、速度等机械量和与机械能量流向有关的开关量。数控的产生依赖于数据载体和二进制形式数据运算的出现。1908年，穿孔的金属薄片互换式数据载体问世；19世纪末，以纸为数据载体并具有辅助功能的控制系统被发明；1938年，香农在美国麻省理工学院进行了数据快速运算和传输，奠定了现代计算机，包括计算机数字控制系统的基础。数控技术是与机床控制密切结合发展起来的。1952年，第一台数控机床问世，成为世界机械工业史上一件划时代的事件，推动了自动化的发展。 现在，数控技术也叫计算机数控技术，目前它是采用计算机实现数字程序控制的技术。这种技术用计算机按事先存贮的控制程序来执行对设备的控制功能。由于采用计算机替代原先用硬件逻辑电路组成的数控装置，使输入数据的存贮、处理、运算、逻辑判断等各种控制机能的实现，均可以通过计算机软件来完成。 数控技术的应用不但给传统制造业带来了革命性的变化，使制造业成为工业化的象征，而且随着数控技术的不断发展和应用领域的扩大，他对国计民生的一些重要行业（IT、汽车、轻工、医疗等）的发展起着越来越重要的作用，因为这些行业所需装备的数字化已是现代发展的大趋势。从目前世界上数控技术及其装备发展的趋势来看，其主要研究热点有以下几个方面。 1.高速、高精加工技术及装备的新趋势 效率、质量是先进制造技术的主体。高速、高精加工技 术可极大地提高效率，提高产品的质量和档次，缩短生产周期和提高市场竞争能力。为此日本先端技术研究会将其列为5大现代制造技术之一，国际生产工程学会（CIRP）将其确定为21世纪的中心研究方向之一。 在轿车工业领域，年产30万辆的生产节拍是40秒/辆，而且多品种加工是轿车装备必须解决的重点问题之一；在航空和宇航工业领域，其加工的零部件多为薄壁和薄筋，刚度很差，材料为铝或铝合金，只有在高切削速度和切削力很小的情况下，才能对这些筋、壁进行加工。近来采用大型整体铝合金坯料“掏空”的方法来制造机翼、机身等大型零件来替代多个零件通过众多的铆钉、螺钉和其他联结方式拼装，使构件的强度、刚度和可靠性得到提高。这些都对加工装备提出了高速、高精和高柔性的要求。 从EMO2001展会情况来看，高速加工中心进给速度可达80m/min，甚至更高，空运行速度可达100m/min左右。目前世界上许多汽车厂，包括我国的上海通用汽车公司，已经采用以高速加工中心组成的生产线部分替代组合机床。美国CINCINNATI公司的HyperMach机床进给速度最大达60m/min，快速为100m/min，加速度达2g，主轴转速已达60000r/min。加工一薄壁飞机零件，只用30min，而同样的零件在一般高速铣床加工需3h，在普通铣床加工需8h；德国DMG公司的双主轴车床的主轴速度及加速度分别达12*!000r/mm和1g。 在加工精度方面，近10年来，普通级数控机床的加工精度已由10m提高到5m，精密级加工中心则从35m，提高到11.5m，并且超精密加工精度已开始进入纳米级(0.01m)。 在可靠性方面，国外数控装置的MTBF值已达6 000h以上 ，伺服系统的MTBF值达到30000h以上，表现出非常高的可靠性。 为了实现高速、高精加工，与之配套的功能部件如电主轴、直线电机得到了快速的发展，应用领域进一步扩大。 2. 5轴联动加工和复合加工机床快速发展 采用5轴联动对三维曲面零件的加工，可用刀具最佳几何形状进行切削，不仅光洁度高，而且效率也大幅度提高。一般认为，1台5轴联动机床的效率可以等于2台3轴联动机床，特别是使用立方氮化硼等超硬材料铣刀进行高速铣削淬硬钢零件时，5轴联动加工可比3轴联动加工发挥更高的效益。但过去因5轴联动数控系统、主机结构复杂等原因，其价格要比3轴联动数控机床高出数倍，加之编程技术难度较大，制约了5轴联动机床的发展。 当前由于电主轴的出现，使得实现5轴联动加工的复合主轴头结构大为简化，其制造难度和成本大幅度降低，数控系统的价格差距缩小。因此促进了复合主轴头类型5轴联动机床和复合加工机床（含5面加工机床）的发展。 在EMO2001展会上，新日本工机的5面加工机床采用复合主轴头，可实现4个垂直平面的加工和任意角度的加工，使得5面加工和5轴加工可在同一台机床上实现，还可实现倾斜面和倒锥孔的加工。德国DMG公司展出DMUVoution系列加工中心，可在一次装夹下5面加工和5轴联动加工，可由CNC系统控制或CAD/CAM直接或间接控制。 3. 智能化、开放式、网络化成为当代数控系统发展的主要趋势 21世纪的数控装备将是具有一定智能化的系统，智能化的内容包括在数控系统中的各个方面：为追求加工效率和加工质量方面的智能化，如加工过程的自适应控制，工艺参数自动生成；为提高驱动性能及使用连接方便的智能化，如前馈控制、电机参数的自适应运算、自动识别负载自动选定模型、自整定等；简化编程、简化操作方面的智能化，如智能化的自动编程、智能化的人机界面等；还有智能诊断、智能监控方面的内容、方便系统的诊断及维修等。 为解决传统的数控系统封闭性和数控应用软件的产业化生产存在的问题。目前许多国家对开放式数控系统进行研究，如美国的NGC(The Next Generation Work-Station/Machine Control)、欧共体的OSACA(Open System Architecture for Control within Automation Systems)、日本的OSEC(Open System Environment for Controller)，中国的ONC(Open Numerical Control System)等。数控系统开放化已经成为数控系统的未来之路。所谓开放式数控系统就是数控系统的开发可以在统一的运行平台上，面向机床厂家和最终用户，通过改变、增加或剪裁结构对象（数控功能），形成系列化，并可方便地将用户的特殊应用和技术诀窍集成到控制系统中，快速实现不同品种、不同档次的开放式数控系统，形成具有鲜明个性的名牌产品。目前开放式数控系统的体系结构规范、通信规范、配置规范、运行平台、数控系统功能库以及数控系统功能软件开发工具等是当前研究的核心。 网络化数控装备是近两年国际著名机床博览会的一个新亮点。数控装备的网络化将极大地满足生产线、制造系统、制造企业对信息集成的需求，也是实现新的制造 模式如敏捷制造、虚拟企业、全球制造的基础单元。国内外一些著名数控机床和数控系统制造公司都在近两年推出了相关的新概念和样机，如在EMO2001展中，日本山崎马扎克（Mazak)公司展出的“CyberProduction Center”（智能生产控制中心，简称CPC)；日本大隈（Okuma）机床公司展出“IT plaza”（信息技术广场，简称IT广场)；德国西门子(Siemens)公司展出的Open Manufacturing Environment（开放制造环境，简称OME）等，反映了数控机床加工向网络化方向发展的趋势。 4. 重视新技术标准、规范的建立 （1） 关于数控系统设计开发规范 如前所述，开放式数控系统有更好的通用性、柔性、适应性、扩展性，美国、欧共体和日本等国纷纷实施战略发展计划，并进行开放式体系结构数控系统规范(OMAC、OSACA、OSEC)的研究和制定，世界3个最大的经济体在短期内进行了几乎相同的科学计划和规范的制定，预示了数控技术的一个新的变革时期的来临。我国在2000年也开始进行中国的ONC数控系统的规范框架的研究和制定。 （2） 关于数控标准 数控标准是制造业信息化发展的一种趋势。数控技术诞生后的50年间的信息交换都是基于ISO6983标准，即采用G，M代码描述如何（how）加工，其本质特征是面向加工过程，显然，他已越来越不能满足现代数控技术高速发展的需要。为此，国际上正在研究和制定一种新的CNC系统标准ISO14649（STEPNC)，其目的是提供一种不依赖于具体系统的中性机制，能够描述产品整个 生命周期内的统一数据模型，从而实现整个制造过程，乃至各个工业领域产品信息的标准化。 STEP-NC的出现可能是数控技术领域的一次革命，对于数控技术的发展乃至整个制造业，将产生深远的影响。首先，STEP-NC提出一种崭新的制造理念，传统的制造理念中，NC加工程序都集中在单个计算机上。而在新标准下，NC程序可以分散在互联网上，这正是数控技术开放式、网络化发展的方向。其次，STEP-NC数控系统还可大大减少加工图纸（约75）、加工程序编制时间（约35）和加工时间（约50）。 目前，欧美国家非常重视STEP-NC的研究，欧洲发起了STEP-NC的IMS计划(1999.1.12001.12.31)。参加这项计划的有来自欧洲和日本的20个CAD/CAM/CAPP/CNC用户、厂商和学术机构。美国的STEP Tools公司是全球范围内制造业数据交换软件的开发者，他已经开发了用作数控机床加工信息交换的超级模型(Super Model)，其目标是用统一的规范描述所有加工过程。目前这种新的数据交换格式已经在配备了SIEMENS、FIDIA以及欧洲OSACA-NC数控系统的原型样机上进行了验证。 编辑本段数控机床程序编制一.数控机床编程的方法 数控机床程序编制的方法有三种：即手工编程、自动编程CAD/CAM 。 1. 手工编程 由人工完成零件图样分析、工艺处理、数值计算、书写程序清单直到程序的输入和检验。适用于点位加工或几何形状不太复杂的零件，但是，非常费时，且编制复杂零件时，容易出错。 2. 自动编程 使用计算机或程编机，完成零件程序的编制的过程，对于复杂的零件很方便。 3. CAD/CAM 利用CAD/CAM软件，实现造型及图象自动编程。最为典型的软件是Master CAM，其可以完成铣削二坐标、三坐标、四坐标和五坐标、车削、线切割的编程，此类软件虽然功能单一，但简单易学，价格较低，仍是目前中小企业的选择。 二.数控机床程序编制的内容和步骤 1. 数控机床编程的主要内容 分析零件图样、确定加工工艺过程、进行数学处理、编写程序清单、制作控制介质、进行程序检查、输入程序以及工件试切。 2. 数控机床的步骤 1) 分析零件图样和工艺处理 根据图样对零件的几何形状尺寸，技术要求进行分析，明确加工的内容及要求，决定加工方案、确定加工顺序、设计夹具、选择刀具、确定合理的走刀路线及选择合理的切削用量等。 同时还应发挥数控系统的功能和数控机床本身的能力，正确选择对刀点，切入方式，尽量减少诸如换刀、转位等辅助时间。 2) 数学处理 编程前，根据零件的几何特征，先建立一个工件坐标系， CNC Technology Numerical control technology, referred to as NC. English: Numerical Control (NC). Refers to numbers, text and symbols to achieve the number of instructions one or more motion control technology machinery and equipment. Usually it controls CNC Technology Is the position, angle, speed and other mechanical quantities and the mechanical energy of the flow switch. CNC production depends on the data carrier and the emergence of binary data operation. 1908, perforated metal sheet interchangeable data carriers come out; the 19th century, the paper carrier for data and control system with auxiliary functions to be invented; 1938, Shannon was at the Massachusetts Institute of fast computing and data transmission, basis of modern computers, including computer based digital control system. CNC technology is closely integrated with the machine control to develop. In 1952, the first CNC machine tools available, to become a landmark in the history of the worlds machinery industry events, and promoted the development of automation. CNC machine tools Now, digital technology, also known as computer numerical control technology, which is currently using the digital process control computer technology. This technique pre-stored by a computer control program to implement control functions on the device. As originally used by computer instead of NC hardware logic circuit device so that the input data storage, processing, computing, logic implementation of various control functions are done by computer software. Edit this paragraph CNC technology trends CNC technology not only to the traditional manufacturing industry has brought revolutionary changes to the manufacturing sector as a symbol of industrialization, and with the continuous development of numerical control technology and expansion of application fields, some of his national economy and major industries (IT, automotive , light industry, medical, etc.) plays an increasingly important role in the development, as these industries for the digital equipment is the major trend of modern development. CNC technology from the world development trend and its equipment, its main research focus in the following areas. 1. High-speed, high precision technology and equipment of the new trend Efficiency, quality is the subject of advanced manufacturing technology. High-speed, high precision technology CNC machine workflow Surgery can greatly improve efficiency, improve product quality and grade, shorten the production cycle and enhance market competitiveness. Japan carries the technology will be included as one of five great modern manufacturing technologies, International Institute of Production Engineering (CIRP) to determine the center of the 21st century research direction. In the car industry, with an annual production of 300,000 beat is 40 seconds / vehicle and car equipment variety processing is one of the key must be addressed; in the aviation and aerospace industry, and its processing for the thin-walled parts and more and thin muscle, stiffness is poor, the material is aluminum or aluminum alloy, high cutting speed and cutting force only in the case of a small can of these bars, wall processing. Recently, the whole aluminum alloy with large blank hollowed out approach to make wings, fuselage and other large part to replace multiple parts through a large number of rivets, screws and other assembly connection means, so that component strength, rigidity and dependability increased. These are made of processing equipment, high speed, high precision and high flexibility. Judging from the EMO2001 exhibition, high-speed machining center feed rate of up to 80m/min, or even higher, and air speed up to 100m/min so. Currently many of the world automobile plant, including Shanghai General Motors, have adopted high-speed machining center part of the production line of machine tool alternatives. CINCINNATI HyperMach U.S. companys largest machine tool feed speed up to 60m/min, quick to 100m/min, acceleration up to 2g, the spindle speed has reached 60000r/min. Aircraft parts machining a thin-walled, only 30min, and the same high-speed milling machine parts in general need to 3h, in the general milling machine to be 8h; Germanys dual-spindle lathe DMG spindle speed and acceleration of up to 12 *! 000r/mm and 1g. In the processing accuracy, the past 10 years, the general level of precision CNC machine tools increased from 10m to 5m, precision machining center from the 3 5m, increased to 1 1.5m, and ultra-precision machining has begun to enter the nano-scale precision (0.01m). In terms of reliability, MTBF values foreign numerical control device has reached more than 6 000h Composed of CNC machine tools Servo system MTBF value reached more than 30000h, showing very high reliability. In order to achieve high-speed, high precision, ancillary features such as spindle, linear motor has been the rapid development of application has been further expanded. 2.5-axis machining and rapid development of machine tool 5-axis machining of three-dimensional surface, can be the best geometry of the cutting tool, not only finish high, but efficiency is greatly improved. Generally believed that 1 5-axis machine tool efficiency can be equal to 2 sets 3 axis machine tools, particularly the use of cubic boron nitride and other superhard materials, high-speed milling of hardened steel cutter part, the 5-axis machining 3-axis than play a more effective process. But in the past due to 5-axis CNC system, the host structure of complex reasons, the price than the 3-axis NC machine tool several times higher, in addition to programming more difficult, limiting the development of 5-axis machine tools. The current emergence of the spindle, making the realization of the complex 5-axis simultaneous machining spindle head structure simplified, the manufacturing difficulty and costs significantly reduced, narrowing the gap between the price of CNC system. So for the first type of complex 5-axis spindle machine tools and machine tool (including 5-face machining) development. In EMO2001 exhibition, New Japan Engineering Machine 5-face machining of composite spindle head, can achieve four vertical plane processing and the processing of any angle, making the 5-sided machining and 5 axis machining can be implemented on the same machine, but also can be achieved and the inverted cone inclined plane processing. German companies exhibit DMUVoution series DMG machining center, a fixture in the next 5-sided machining and 5 axis joint NC Device Action processing, system control by the CNC or CAD / CAM controlled directly or indirectly. 3. Intelligent, open, network development as the major contemporary trends in numerical control system 21 numerical control equipment will be sure the intelligent system, intelligent content included in all aspects of the numerical control system: the pursuit of processing efficiency and processing quality of intelligence, such as the adaptive control process, process parameters automatically generation; to improve the performance and easy to use intelligent connection, such as feedforward control, adaptive computing motor parameters, automatic identification of load select models, self-tuning, etc.; simplify programming, simplifying operational aspects of intelligence, such as smart of automatic programming, intelligent man-machine interfaces; also intelligent diagnosis, intelligent control aspects, to facilitate system diagnostics and maintenance. CNC system to address the closure of the traditional CNC applications and industrial production problems. Many countries now open CNC system of research, such as the United States NGC (The Next Generation Work-Station/Machine Control), the EC OSACA (Open System Architecture for Control within Automation Systems), Japan OSEC (Open System Environment for Controller), China, ONC (Open Numerical Control System) and so on. Open CNC system has become a numerical control system of the future of the road. The so-called open-CNC system is CNC system development can be run in a unified platform, for the machine tool manufacturers and end users, by changing, adding or cutting out the structure object (NC function) to form a series, and easily to users special applications and technical know-how into the control system, rapid implementation of different varieties, different grades of open CNC system, the formation of a distinct brand personality. The open numerical control system architecture specification, communication specifications, configuration specifications, operating platform, function libraries and CNC numerical control system software development tools, system function is the core of the current study. Network numerical control equipment is well-known international machine tool fair the past two years, a new bright spot. NC network equipment will greatly satisfy the production lines, manufacturing systems, manufacturing information integration needs of enterprises, but also achieve new manufacturing CNC lathe Models such as agile manufacturing, virtual enterprises, global manufacturing the base unit. Some well-known at home and abroad, and CNC CNC machine tools manufacturing companies have introduced in recent years related to new concepts and prototype, as in EMO2001 exhibition, Japan Yamazaki Mazak (Mazak) that the company exhibits CyberProduction Center (intelligent production control center, referred to as CPC); Japan Okuma (Okuma) Machine Company exhibited IT plaza (Information Technology Square, referred to as IT Plaza); Germanys Siemens (Siemens) that the company exhibits Open Manufacturing Environment (open manufacturing environment, referred to as OME), etc. , reflecting the CNC machining direction to the network trend. 4. Emphasis on new technology standards, the establishment of norms (1) on the numerical control system design and development of norms As mentioned earlier, open CNC system has better versatility, flexibility, adaptability, scalability, the United States, the European Community and Japan have to implement the strategic development plan, and the open architecture CNC system specification (OMAC , OSACA, OSEC) research and development, the worlds three largest economies in the short term were almost the same as the scientific program and the standard formulation, indicating a numerical control technology, the advent of a new period of change. China also started in 2000, CNC Chinas regulatory framework ONC research and development. (2) on the NC Standard NC standard is the development of manufacturing information is a trend. CNC technology 50 years after the birth of the exchange of information is based on ISO6983 standards, which adopts the G, M code describes how (how) processing, the essential characteristics of process-oriented, obviously, he can not meet modern CNC technology high-speed development. To this end, the international research and development is a new CNC system standard ISO14649 (STEP-NC), the aim is to provide a specific system does not rely on a neutral mechanism to describe the entire product CNC milling machine Life cycle of the unified data model, enabling the entire manufacturing process, as well as various industry standardization of product information. STEP-NC may be the emergence of a revolution in the field of numerical control technology, the development of numerical control technology for the manufacturing sector as a whole, will have far-reaching impact. First, STEP-NC manufacturing presents a new concept, the concept of traditional manufacturing, NC machining program are concentrated in a single computer. Under the new standard, NC programs can be distributed on the Internet, which is open numerical control technology and network development. Secondly, STEP-NC CNC system can also reduce processing drawings (about 75%), processing the time (about 35%) and processing time (about 50%). At present, Europe and the United States attaches great importance to the research STEP-NC, the European launch of the IMS STEP-NC program (1999.1.1 2001.12.31). To participate in this program are from Europe and Japan 20 CAD / CAM / CAPP / CNC users, vendors and academic institutions. U.S. STEP Tools is a global exchange of data within the software development industry, he has developed for the exchange of information of CNC machining super model (Super Model), whose goal is a unified specification describes all the process. Such new data exchange format has been equipped with SIEMENS, FIDIA and the European OSACA-NC NC system is verified on the prototype. Edit this paragraph programming CNC machine tools One. CNC machine programming method CNC machine tool programming in three ways: the manual programming, automatic programming and Machining