机械设计制造及其自动化专业英语.ppt

1、word,Computer-Aided Manufacturing 计算机辅助制造 blacksmith n. 锻工，铁匠 adaptive dptv adj. (自)适应的 assembly sembli n. ; v. 装配 evolve ivlv v. 进化，发展，进展 commission kmin n. ; v. 代理，委托，委任 tangential tndenl adj. 切线的，肤浅的，略为触及的,Manufacturing Process,1,word,distribute distribju:t v. 分 布 mass-production techniques 大批量生产

2、技术 economy of scale 规模经济 versus v:ss prep. 与比较，对，作为的函数 semiautomatic semi:tmtik adj. 半自动的 manual mnjul adj. 手工的,Manufacturing Process,2,Manufacturing Process,Computer-Aided manufacturing 计算机辅助制造（技术） The scientific study of metal-cutting and automation techniques is products of the twentieth century

3、senturi. Two pioneers ,painis of these techniques were Frederick Taylor and Henry Ford. 从科学上进行研究金属切削和自动化技术研究起始于第二十世纪。这些技术的先驱者是弗雷德里克泰勒和亨利.福特。,3,During the early 1900s, the improving U.S. standard of living brought a new high in personal wealth. The major result was the increased demand for durable dr

4、bl goods. 20世纪初美国日益提高的生活水平将个人财富带到一个新的高度。这种现象主要影响就是对耐用消费品的需求的增长。,Computer-Aided manufacturing,4,This increased demand meant that manufacturing could no longer be treated tri:td as a blacksmith trade treid, and the use of scientific study was employed in manufacturing analysis. 日益增长的需求意味着制造业不再是简单的手工作坊

5、式的行业，而应该在制造业中引入科学化的研究手段。,Computer-Aided manufacturing,5,Taylor pioneered studies in “scientific management” in which methods for production by both men and machines were studied. 泰勒开创了“科学管理”的研究，透过人员和机器研究生产的方法。,Computer-Aided manufacturing,6,Taylor also conducted kndktd metal cutting experiments at t

6、he Midvale Steel Company that lasted 26 years and produced 400 tons of metal chips. 泰勒还在米德韦尔钢铁公司进行金属切削试验，该项试验长达26年之久并生产了近400吨重的金属铁屑。,Computer-Aided manufacturing,7,The result of Taylors metal-cutting experiments was the development of the Taylor tool-life equation that is still used in industry ndst

7、ri today. 泰勒的金属切削实验最终导致了泰勒刀具寿命公式的发现，该公式目前仍然被工业界所采用。,Computer-Aided manufacturing,8,This tool-life equation is still the basis of determining economic metal cutting and has been used in adaptive controlled machining. 刀具使用寿命仍然作为最基本的判断金属切削经济与否的依据。同时，该刀具寿命公式还被用于自适应控制加工。,Computer-Aided manufacturing,9,He

8、nry Fords contributions took a different turn from Taylors. Ford refined rifaind and developed the use of assembly lines for the major component manufacturer of his automobile. 亨利.福特的研究成果与泰勒不同。福特优化和开发了装配生产线的应用，这种装配生产线应用于他的汽车主要零部件的制造。,Computer-Aided manufacturing,10,Ford felt that every American fami

9、ly should have an automobile, and if they could be manufactured inexpensively enough then every family would buy one. Several mechanisms were developed at Ford to accommodate kmdeit assembly lines. 福特认为每个美国家庭都应该拥有一辆汽车。如果能将汽车的价格降低到人们的购买力水平上(他们制造的汽车足够廉价的话)，那么每个家庭就会购买一辆汽车。福特公司开发了一些设备（机械装置）以适应装配生产线。,Com

10、puter-Aided manufacturing,11,The automation that Ford developed was built into the hardware, and Ford realized that significant demand was necessary to offset the initial development and production costs of such systems. 福特开发的自动化是建立在硬件中的，福特意识到需要大量的需求来抵消这种系统的初始开发和生产成本。,Computer-Aided manufacturing,12

11、,Although manufacturing industries continued to evolve, it was not until the 1950s that the next major development occurred. 虽然制造业的研发一直持续不断，但新的一轮大发展是在20世纪50年代才出现的。,Computer-Aided manufacturing,13,For some time, strides strad to reduce human involvement in manufacturing were being taken. Specialty sp

12、elti machines using cams and other “hardwired” logic controllers had been developed. 长期以来，人们一直致力于减少制造过程中的人为参与。已经开发出了采用凸轮和其他“硬连线”逻辑控制器的专用设备。,Computer-Aided manufacturing,14,The U.S. Air Force recognized reknazd the development time required to produce this special equipment and that the time required

13、 to make only small sequence changes was excessive kssv. 美国空军意识到，用来生产这些专用设备的研发时间和用来仅作程序小改变的时间都是很长的(过多的)。,Computer-Aided manufacturing,15,As a result, the Air Force commissioned the Massachusetts mstu:sts Institute of Technology to demonstrate dmnstret programmable or numerically controlled (NC) mach

14、ines (also known as “softwired” machines) . With this first demonstration in 1952 came the beginning of a new era r in manufacturing. 因此，美国空军委托麻省理工学院开发(展示)可编程的数字化控制器，也称“软连线”设备。1952年的这次首创开始了制造业的新纪元。,Computer-Aided manufacturing,16,Since then, digital computers have been used to produce input either i

15、n a directed manner to many NC machines, direct numerical control (DNC), or in a more dedicated control sense, computer numerical control (CNC). 从那时起，数字计算机就被用来当做输入设备，要么以直接方式输入到NC设备中，直接数字控制（DNC），要么用更专用的控制传感，即计算机数字控制（CNC）。,Computer-Aided manufacturing,17,Today, machine control languages such as APT (A

16、utomatic Programming Tool) have become the standard for creating tool control for NC machines. 如今，机床控制语言比如说自动编程工具 ，已经成为数控机床创建工具控制的标准了。,Computer-Aided manufacturing,18,It is interesting to note that much of the evolution in manufacturing has come as a response to particular changes during different p

17、eriod. 有意思的是，制造业的许多发展都对应于不同历史时期的特定的变化。,Computer-Aided manufacturing,19,For instance, the technology that evolves in the nineteenth century brought with it the need for higher-precision machining. (this resulted in the creation of many new machine tools, a more refined machine design, and new product

18、ion processes.) 例如，19世纪的工业革命促进了人们对较高加工精度的需求（从而促进了许多新型刀具的研发、精密机床的设计以及新的生产工艺）。,Computer-Aided manufacturing,20,The early twentieth century became an era of prosperity and industrialization that created the demand necessary for mass-production techniques. 二十世纪初期成为一个繁荣的、工业化的年代，这个年代也创造了大规模生产技术所必须的产品需求。,C

19、omputer-Aided manufacturing,21,In the 1950s it was estimated that as the speed of an aircraft increased, the cost of manufacturing the aircraft (because of geometric complexity) increased proportionately with the speed. 20世纪50年代，据估计，随着飞行速度增大，这个飞机的制造成本也会以这个速度同样比例的增加(因为其复杂程度是以几何级数增加的)。,Computer-Aided

20、manufacturing,22,The result of this was the development of NC technology. A few tangential notes on this history include the following. 也正是这个原因导致了NC技术的发展。在这段历史时期内一些次要的记录如下：,Computer-Aided manufacturing,23,As the volume of parts manufactured increases, the production cost for the parts decrease (this

21、 is generally known as “economy of scale”). Some of the change in production cost is due to fixed versus variable costs. 当零部件的制造数量增加时，那么，这个零件的生产成本会减小，这种现象通常被称之为“经济规模”。生产成本某些变化是由于固定成本与可变成本的比例改变。,Computer-Aided manufacturing,24,For instance, if , only a single part is to be produced (such as a space v

22、ehicle), all of the fixed costs for planning and design (both product and process) must be absorbed by the single item. 例如，只生产一个的话（如一个宇宙飞船），那么，所有固定成本，包括规划、设计(包含产品和加工)，都只能由这个单一项目去承担。,Computer-Aided manufacturing,25,If, however, several parts are produced, the fixed charge can be distributed over seve

23、ral parts. 如果生产多个的话，固定成本可以分摊到这多个当中。,Computer-Aided manufacturing,26,Changes in production cost, not reflected in this simple fixed-versus variable-cost relationship, are usually the result of different manufacturing procedures-transfer-line techniques for high-volume items versus job-shop procedures

24、 for low-volume items. 生产成本的变化并不仅仅是简单的固定成本与可变成本间的关系。通常， 这是不同制造方法的结果，自动化生产线用于大批量产品，加工车间用于小批量产品。,Computer-Aided manufacturing,27,An automated manufacturing system consists of a collection of automatic or semiautomatic machines linked together by a “intrasystem” material-handling system. 自动化制造系统由一系列的自动

25、化机床或半自动化机床，及将他们连接到一起的内部物料传送系统组成。,Automated manufacturing system,28,These systems have been around since before Henry Ford began to manufacture his Model T on his moving assembly line. 这种系统大约起始于Henry Ford 在他的移动装配线上开始生产T型汽车的时候。,Automated manufacturing system,29,These automated systems have been used t

26、o produce machined components, assemblies, electrical components, food products, chemical products, etc. 这些自动化系统被用来生产机器零部件，总成，电器元件，食品，化工产品等。,Automated manufacturing system,30,The total number of products produced on a single system varies verz with the production methods. However, the principle of designing the production systems are the same independently of the product being manufactured. 单一系统的生产总量是随这个系统的生产方法的改变而变化的。然而，不管生产什么产品，设计生产系统的原则是一样的。,Automated manufacturing system,31,The workstations in a production system can be manual, semiautomatic or fully automatic. The automatic