机电英语lesson3

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1、Lesson 3 Numerical Control and Automatic Machines 数控与自动机器,Section I Words and Phrases Section II Text and Translation Section III Exercises and Answers,词,英,汉,练,End,Next,答,Section I Words and Phrases,tool tu:l v.给装配工具、机床和仪器;用工具加工,使用工具 n.工具,用具cutting tool 刀具 machine tool 机床过去式:tooled 过去分词:tooled 现在分词:

2、tooling 复数:tools例句:I have a complete set of carpenters tools.我有全套的木工工具。 prohibitive prhibitiv adj.禁止性的,抑制的 adv.禁止地 n.禁止prohibitive prices 过高的价格使人不敢买例句:The cost of repairs would be prohibitive.修理费会高得令人望而却步。 job-lot n.杂乱的一堆,论堆的廉价品,一次生产的部分或少数产品job-lot amount 单批量例句: I bought that jug as part of a job lo

3、t at the church jumble sale. 我在教堂的旧杂货义卖上买了一批杂货,基中包括那只壶。jumble dmbl及物动词 vt. 使混乱;使杂乱,Topic,Above,Next,End,Section I Words and Phrases,re-run (reran, rerun; rerunning) v. (使)再开动(运转), (使)重新开动 down-time n.停机时间,故障时间例句:They got excited time after time and cooled down time after time too. 他们一次次地激动起来,又一次次地冷却

4、下去。 template 5templit n. 样(模,型)板,样规例句:It serves as a template. 它相当于模板。 semiautomatic 5semi:t5mtik adj.半自动的 semiconductor n. 半导体例句:The machine is semiautomatic. 这架机器是半自动的。numerical nju:5merikl adj.数字的, 用数字表示的, 数值的 eliminate ilimineit vt.排除,消除,消灭 ; (比赛中)淘汰 equivalent ikwivlnt adj.相等的,相同的 ;等价的,等值的;等量的;

5、等效的,Topic,Above,Next,End,Section I Words and Phrases,contour5kn t n.外形,轮廓;等高线过去式:contoured 过去分词:contoured 现在分词:contouring复数:contours例句:the contours of the countryside 乡村的轮廓 flexibility ,fleksbiliti n.柔韧性;机动性,灵活性,易曲性;适应性,弹性例句:Her great strength lies in her flexibility.她的优势在于她灵活变通。in turn依次;轮到 textile

6、 tekstail n.纺织品;纺织原料Cadj.纺织的 blueprint blu:print n.蓝图;设计图;计划 vt.将.制成蓝图;计划 via vai prep. 经由;取道;通过,凭借,Topic,Above,Next,End,Section II Text,The major disadvantage of machine tool lies in the economics of the process. It is expensive to a machine tool for automatic production. Therefore, unless the part

7、 is to be made in very large numbers, the cost becomes prohibitive. Great need exists for a method that permits rapid automatic production, economical in job-lot amounts. The answer has been found in the numerical control of machine tools. In numerical control, the blueprint for a part is converter

8、into a punched paper-type instruction, which is adapted via a computer to direct the operation of a specific machine tool. Thus general purpose machine tools described in previous chapters-are instructed to machine a part according to information stored on a roll of tape. The tape can be re-run for

9、copies of the same part or can be stored for future use. Furthermore, other tapes can be used to command the same machine tool to make other parts. There is a wide area of performance duplication between numerical control and automatics. Numerical control, however, offers more flexibility, lower too

10、ling cost, quicker changes, and less machine down-time.,Topic,Above,Next,汉,End,Section II Text,In machining contours, numerical control can mathematically translate the defined curve into a finished product, saving time and eliminating templates. This can in turn improve accuracy. Another advantage

11、appears to be great saving of machine time, the equivalent of increasing productive capacity with no increase in facilities.Automation is no new development. Semiautomatic machines have been used in the textile industry and in engineering for many years. These machines merely require to be set up, l

12、oaded and started. Then, for a limited time, they will run on their own, with only an operator to watch them. From these have been developed machines known as transfer machines, found mostly in the motor-manufacturing industry. In production units using these, each stage in the manufacture of an art

13、icle is carried out by one fully-automatic machine in a line of machines. The loading of the article to be machined is automatic, as in its transfer from one machine to the next.,Topic,Above,Next,汉,End,Section II Text,Most of the transfer machine currently in operation employ electrical, pneumatic o

14、r hydraulic techniques.Although automatic control by pneumatic and hydraulic means has been developed to a high degree of efficiency, the more recently developed electronic techniques offer many advantages over them. Electronic methods allow for greater speed, accuracy and flexibility in the operati

15、on of control systems. They also make possible the processing of information. Information, both from within the control system itself and from outside sources, can be electronically processed. Thus the control extremely complex processes can be carried out automatically.,Topic,Above,Next,汉,End,Secti

16、on II Translation,迄今所叙述的机床自动化的主要不利条件是这项技术的经济性。装备一台进行自动化生产的机床是很费钱的。因此,除非零件的生产量非常大,否则,机床自动化就会因成本过高而变得不可行。非常需要一种在单批量生产中既快速又经济的自动化生产方法。这种方法已经有了,这就是数控机床技术。采用数控技术时,零件的图纸先被转换成穿纸孔带型的指令,经计算机改编后用来控制专用机床进行作业。这样,通用机床-前面已经作了叙述-按照储存在磁带上的信息去加工零件。磁带可以反复用来重复加工相同的零件,也可以储存起来以备后用。而且,可以用其他磁带来“命令”同一部机床加工另外的零件。数控和自动化之间很多性

17、能是一样的。然而,数控技术更灵活,装备机床的花费更少,更换更快,而且停机维修时间更短。,Topic,Above,Next,英,End,Section II Translation,在加工外形轮廓时,数控能够用数学方法将确定的曲线转换成成品,既节省时间,又无需样板,还可提高加工精度。另一个优点看来是能大大节省时间,也就是说不增添设备就能提高生产率。自动化并不是什么新鲜事。半自动机器已在纺织工业和工程中使用多年。这些机器仅需在工作前安装调试好,加上负荷启动就行了。然后,在一段有限的时间内,它们就会自行工作,只需一个操作人员照看它们就够了。人们由这类机器研制出了传输机,它们多数用在汽车制造工业中。在使用这些机器的生产厂家中,工件加工的各个阶段都是在一条机器作业线上的某台全自动机器上完成的。待加工工件是自动装上机器的,从一台机器传送下一台机器也是自动的。,

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