数控外文翻译-数控加工技术概述【中英文WORD】【中文2800字】
数控外文翻译-数控加工技术概述【中英文WORD】【中文2800字】,中英文WORD,中文2800字,数控,外文,翻译,加工,技术,概述,中英文,WORD,中文,2800
【中文2800字】数控加工技术概述1.1 数控加工的特点 控制机床实现自动运转。数控加工经历了半个世纪的发展已成为应用于当代各个制造领域的先进制造技术。数控加工的最大特征有两点:一是可以极大地提高精度,包括加工质量精度及加工时间误差精度;二是加工质量的重复性,可以稳定加工质量,保持加工零件质量的一致。也就是说加工零件的质量及加工时间是由数控程序决定而不是由机床操作人员决定的。数控加工具有如下优点:1. 提高生产效率; 2. 不需熟练的机床操作人员; 3. 提高加工精度并且保持加工质量; 4. 可以减少工装卡具; 5. 可以减少各工序间的周转,原来需要用多道工序完成的工件,用数控加工可以一次装卡完成,缩短加工周期,提高生产效率。 6. 容易进行加工过程管理; 7. 可以减少检查工作量; 8. 可以降低废、次品率; 9. 便于设计变更,加工设定柔性; 10. 容易实现操作过程的自动化,一个人可以操作多台机床; 11. 操作容易,极大减轻体力劳动强度 随着制造设备的数控化率不断提高,数控加工技术在我国得到日益广泛的使用,在模具行业,掌握数控技术与否及加工过程中的数控化率的高低已成为企业是否具有竞争力的象征。数控加工技术应用的关键在于计算机辅助设计和制造(CAD/CAM)系统的质量。如何进行数控加工程序的编制是影响数控加工效率及质量的关键,传统的手工编程方法复杂、烦琐,易于出错,难于检查,难以充分发挥数控机床的功能。在模具加工中,经常遇到形状复杂的零件,其形状用自由曲面来描述,采用手式编程方法基本上无法编制数控加工程序。近年来,由于计算机技术的迅速发展,计算机的图形处理功能有了很大增强,基于CAD/CAM技术进行图形交互的自动编程方法日趋成熟,这种方法速度快、精度高、直观、使用简便和便于检查。CAD/CAM技术在工业发达国家已得到广泛使用。近年来在国内的应用也越来越普及,成为实现制造业技术进步的一种必然趋势。1.2 数控机床 20世纪40年代末,美国开始研究数控机床,1952年,美国麻省理工学院(MIT)伺服机构实验室成功研制出第一台数控铣床,并于是1957年投入使用。这是制造技术发展过程中的一个重大突破,标志着制造领域中数控加工时代开始。数控加工是现代制造技术的基础,这一发明对于制造行业而言,具有划时代的意义和深远的影响。世界上主要主要工业发达国家都十分重视数控加工技术的研究的发展。我国于是1958年开始研制数控机床,成功试制出配有电子数控系统的数控机床,1965年开始批量生产配有晶体管数控系统的三坐标数控铣床。经过几十年的发展,目前的数控机床已经在工业界得到广泛应用,在模具制造行业的应用尤为普及。数控机床种类繁多,一般将数控机床分为16大类: 数控车床(含有铣削功能的车削中心) 数控铣床(含铣削中心) 数控镗床 以铣镗削为主的加工中心 数控磨床(含磨削中心) 数控钻床(含钻削中心) 数控拉床 数控刨床 数控切断机床 数控齿轮加工机床 数控激光加工机床 数控电火花切割机床(含电加工中心) 数控板材成型加工机床 数控管料成型加工机床 其他数控机床 模具制造常用数控加工机床有:数控铣床、数控电火花成型机床、数控电火花线切割机床、数控磨床和数控车床。数控机床通常由控制系统、伺服系统、检测系统、机械传动系统及其它辅助系统组成。控制系统用于数控机床的运算、管理和控制,通过输入介质得到数据,对这些数据进行解释和运算并对机床产生作用;伺服系统根据控制系统的指令驱动机床,使刀具和零件执行数控代码规定的运动;检测系统则是用来检测机床执行件(工作台、转台、滑板等)的位移和速度变化量,并将检测结果反馈到输入端,与输入指令进行比较,根据其差别调整机床运动;机床传动系统是由进给伺服驱动元件至机床执行件之间的机械进给传动装置;辅助系统种类繁多,如:固定循环(能进行重复加工)、自动换刀(可交换指定的刀具)、传动间隙补偿(补偿机械传动系统产生的间隙误差)等等。 在数控加工中,数控铣削加工最为复杂,需解决的问题也最多。除数控铣削加工之外的数控线切割、数控电火花成型、数控车削、数控磨削等的数控编程各有其特点,本书将重点介绍对数控加工程序编制具有指导意义的数控铣削加工的数控编程。1.3 数控加工 数控加工是将待加工零件进行数字化表达,数控机床按数字量控制刀具 和零件的运动,从而实现零件加工的过程。 被加工零件采用线架、曲面、实体等几何体来表示,CAM系统在零件几何体基础上生成刀具轨迹,经过后置处理生成加工代码,将加工代码通过传输介质传给数控机床,数控机床按数字量控制刀具运动,完成零件加工。其过程如下图所示:【零件信息】【CAD系统造型】【CAM系统生成加工代码】【数控机床】【零件】(1)零件数据准备:系统自设计和造型功能或通过数据接口传入CAD数据,如STEP,IGES,SAT,DXF,X-T等;在实际的数控加工中,零件数据不仅仅来自图纸,特别在广泛采用Internet网的今天,零件数据往往通过测量或通过标准数据接口传输等方式得到。(2)确定粗加工、半精加工和精加工方案。(3)生成各加工步骤的刀具轨迹。(4)刀具轨迹仿真。(5)后置输出加工代码。(6)输出数控加工工艺技术文件。(7)传给机床实现加工。1.4 数控编程系统 数控加工机床与编程技术两者的发展是紧密相关的。数控加工机床的性能提升推动了编程技术的发展,而编程手段的提高也促进了数控加工机床的发展,二者相互依赖。现代数控技术下在向高精度、高效率、高柔性和智能化方向发展,而编程方式也越来越丰富。 数控编程可分为机内编程和机外编程。机内编程指利用数控机床本身提供的交互功能进行编程,机外编程则是脱离数控机床本身在其他设备上进行编程。机内编程的方式随机床的不同而异,可以“手工”方式逐行输入控制代码(手工编程)、交互方式输入控制代码(会话编程)、图形方式输入控制代码(图形编程),甚至可以语音方式输入控制代码(语音编程)或通过高级语言方式输入控制代码(高级语言编程)。但机内编程一般来说只适用于简单形体,而且效率较低。机外编程也可以分成手工编程、计算机辅助APT编程和CAD/CAM编程等方式。机外编程由于其可以脱离数控机床进行数控编程,相对机内编程来说效率较高,是普遍采用的方式。随着编程技术的发展,机外编程处理能力不断样强,已可以进行十分复杂形体的灵敏控加工编程。 在20世纪50年代中期,MIT伺服机构实验室实现了自动编程,并公布了其研究成果,即APT系统。60年代初,APT系统得到发展,可以解决三维物体的连续加工编程,以后经过不断的发展,具有了雕塑曲面的编程功能。APT系统所用的基本概念和基本思想,对于自动编程技术的发展具有深远的意义,即使目前,大多数自动编程系统也在沿用其中的一些模式。如编程中的三个控制面:零件面(PS)、导动面(DS)、检查面(CS)的概念:刀具与检查面的ON、TO、PAST关系等等。 随着微电子技术和CAD技术的发展,自动编程系统也逐渐过渡到以图形交互为基础的与CAD集成的CAD/CAM系统为主的编程方法。与以前的语言型自动编程系统相比,CAD/CAM集成系统可以提供单一准确的产品几何模型,几何模型的产生和处理手段灵活、多样、方便,可以实现设计、制造一体化。4Outline of Numerical control processing technology1.1 NC machining characteristics Automatic machine control operations. NC experienced 50 years of development have become used in the manufacture of various contemporary advanced manufacturing technologies. NC greatest features are two-fold : First, it will greatly improve the precision, including precision machining quality and processing time error precision; Second, the quality of processing repeatability, stable processing quality, machining parts to maintain the same quality. That is machined quality and processing time by the NC program is not decided by the machine operator personnel decisions. NC has the following advantages : 1. Increasing production efficiency;2.Not skilled machine operators;3. Improve processing accuracy and to maintain the quality processing; 4. Tooling fixtures can be reduced; 5. The process can reduce the flow, the original multi-channel needs to complete its work processes, NC with a loaded card can be completed, shortening the processing cycle and improve production efficiency.6. Easy processing management; 7. Inspection can be reduced workload; 8. Waste can be reduced, the rate of defective; 9. Ease of design change, set flexible processing; 10. Easy operation process automation, a person can operate multiple machine; 11. Easy to greatly reduce the manual intensity With manufacturing equipment, NC rate rising CNC Machining Technology in China is increasingly widely used. Die industry, technical or master NC machining process and the NC rate of the enterprises has become competitive symbol. NC technology is the key to computer-aided design and manufacturing (CAD/CAM) system quality. How the NC Program for the NC affect the efficiency and quality of the key, traditional manual programming complex, cumbersome and easily mistake and it is difficult to check, to give full play to the functions of CNC machine tools. Die processing, which often face complex shape parts, the shape of freedom to describe the surface, hand-programming is basically impossible NC establishment procedures. In recent years, computer technology and rapid development of computer graphics processing function has been greatly enhanced, Based on interactive graphics CAD/CAM for automatic programming matures, this method is faster, technology high precision and intuitive, easy to use and can be easily checked. CAD/CAM in industrialized countries has been widely used. Technology In recent years, domestic applications are becoming more and more popular, and the realization of progress in manufacturing technology is an inevitable trend. 1.2 CNC machine tools 20 late 1940s, the United States began to study CNC machine tools, in 1952, Massachusetts Institute of Technology (MIT) Laboratory Servomechanism successfully developed the first CNC milling machine, So in 1957 and put into use. This is the process of manufacturing technology development of a major breakthrough in the field of manufacture marked NC era. NC machining of modern manufacturing technology foundation for the invention of the manufacturing sector, The epoch-making significance and far-reaching impact. The worlds major industrialized countries are the main attaches great importance to the NC processing technology research development. So in 1958 China began developing CNC machine tools, successfully produce the NC equipped with the electronic system of NC machine tools, began mass production in 1965 equipped with a transistor CNC Milling Machine CNC CMM. After several decades of development, the NC machine tools in the industrial sector has been widely used, Die manufacturing industry in the application is particularly popular. CNC machine tools, and a large variety of CNC machine tools in general will be divided into 16 categories : CNC lathes (including milling function of turning center) CNC Milling Machine (including milling center) Boring Machine CNC Milling Boring - based CNC Machining Center Grinder (including grinding center) NC drilling (including drilling) NC NC Broacher peelers NC-cutting CNC machine tools Gear Machine CNC laser cutting machines EDM CNC cutting machine tools (including Canada - the center) NC Sheet Molding Machine CNC tube Molding Machine Other CNC machine tools Die Manufacturing CNC machine tools used : CNC milling machine, CNC EDM machine, NC WEDM. CNC grinding machine and CNC lathe. CNC machine tools usually by the control system, servo systems, detection systems, mechanical drive system and other auxiliary system. Control systems for CNC machine operation, management and control, through the importation of media data are available, These data interpretation and Machine Operators also have an effect; Servo control system based on the order-driven machine, tools and spare parts to enable the implementation of the NC code campaigns; Detection System is the machine used to test the implementation of documents (workstations, Turntable, skateboards, etc.) displacement and velocity variation, and test results of the feedback input, and input commands, According to adjust their differences machine movement; Machine transmission was made by the servo actuator to the implementation of Machine between the mechanical pieces of feed drive devices; supporting a wide range of systems, such as : fixed cycle (capable of repetition processing), automatic tool change (exchangeable designated Tool), Transmission Clearance Compensation (compensation mechanical drive system of clearance error), and so on. CNC Machining, CNC Milling most complex, the need to solve the problem the most. In addition to CNC milling outside the CNC wire cutting, CNC EDM, CNC turning, Grinding the NC NC programming have their own characteristics, The book focuses on the NC programming is of guiding significance to the NC NC machining program.1.3NC NC will be processing parts for digital expression, according to figures CNC machine tool and volume control parts Campaign thus achieving Machining process. Be machined with thread racks, surface, geometric entities to, CAM system in the body parts on the basis of geometric tool path generation after generation after processing processing code, processing code pass through the transmission medium CNC machine tools, CNC machine control by Digital Tool campaigns, to complete the processing components. The process as in the figure below : Parts information CAD system modeling CAM system processing code generation NC Machine Annex : (1) data preparation components : system design and modeling from the functional data interface or through the introduction of CAD data, such as STEP, IGES, SAT, DXF, X-T; In the actual NC, Parts of data not only from the drawings, especially in the widely used Internet today, Web Parts are often measured data or data through standard interfaces such as transmission manner. (2) to determine roughing, semi-finishing and finishing the program. (3) Generation of the processing steps of the tool path.(4) tool path simulation.(5) Purchase export processing code.(6) NC output document processing technology.(7) pass machining machine tools.1.4 NC Programming System NC machine tools and programming technology is the development of two closely related. NC machine tools to enhance the performance of a program to promote technological development, and programming tools to enhance the promotion of NC machine tools, the two interdependent. NC modern techniques to the high-precision, high-efficiency, high flexibility and intelligent direction, and the programming is increasingly abundant. CNC programming can be divided into machine programming and the aircraft program. Programming inside the use of CNC machine tool itself interactive programming functions, aircraft program is CNC machine tool itself from the other equipment on the program. Programming inside the random bed different and the difference can manual mode input control code line by line (manual programming), Interactive input control code (conversational programming), and input control graphics code (Graphics Programming) even voice input control code (voice Programming), or through high-level language code input control (Advanced Language Programming). But inside Programming generally applies only to simple physical, but also less efficient. The plane can be divided into programming manual programming, and computer-aided programming CAD/CAM APT programming, and so on. The aircraft because of its programming will be freed from the NC machine tool CNC programming, relative machines run more efficient programming, is a commonly used method. With programming technology, aircraft handling capabilities of programming-like, can have very complex physical sensitive control processing program. In the 20th century, the mid-1950s, MIT Laboratory Servomechanism achieve automatic programming, and published the results of its research, APT system. The early 1960s, the development APT system can solve the three-dimensional objects for processing program, After subsequent continues to develop, with a sculptured surface functional programming. APT system with the basic concepts and ideas, automatic programming for the development of far-reaching significance Even now, most automatic programming system which is also used by some model. Programming such as control of three areas : parts surface (PS), hyperkinetic surface (DS), surface inspection (CS) concept : Tool and inspection of surface ON, TO, PAST relations, and so on. With microelectronic technology and the development of CAD technology. automatic programming system is a gradual transition to a graphics-based interactive and integrated CAD-based systems CAD/CAM programming method. Previous language-based automatic programming systems, CAD/CAM integrated system can provide accurate product of a single geometric model. geometric model of production and processing means flexibility, diversity, convenience, can achieve the design and manufacturing integration. 5
收藏