機(jī)械工程專業(yè)英語(yǔ)課件--L17

1、English for Mechanical Engineering機(jī)械工程專業(yè)英語(yǔ)1機(jī)械工程專業(yè)英語(yǔ)預(yù)備知識(shí) 一、預(yù)備知識(shí)Fixture A fixture is a workholding or support device used in the manufacturing industry. What makes a fixture unique is that each on is built to fit a particular part or shape. The main purpose of a fixture is to locate and in some cases

2、hold a workpiece during either a machining operation or some other industrial process. A jig differs from a fixture in that it guides the tool to its correct position in addition to locating and supporting the workpiece.Lesson 34 Automatic Fixture Design2機(jī)械工程專業(yè)英語(yǔ)預(yù)備知識(shí) 一、預(yù)備知識(shí)The primary purposes of ji

3、gs and fixtures is to:Reduce the cost of production Maintain consistent quality Maximize efficiency Enable a variety of parts to be made to correct specifications Lesson 34 Automatic Fixture Design3機(jī)械工程專業(yè)英語(yǔ)預(yù)備知識(shí) 一、預(yù)備知識(shí)Grippers by ZAYTRAN are universally applicable out-of-the-box. The use of third-gen

4、eration ZAYTRAN technology and the selection of super tough, corrosive resistant materials allow these products to efficiently serve day-to-day as well as tough, nearly impossible gripper applications BUT are priced competitively with commodity products! ZAYTRAN gripper technology provides precision

5、 in extreme environments such as clean rooms, grinder loading, automotive, and die casting.Lesson 34 Automatic Fixture Design4機(jī)械工程專業(yè)英語(yǔ)預(yù)備知識(shí) 一、預(yù)備知識(shí)ZAYTRANs patented helix synchronization system facilitates extremely long strokes. In addition, wear is minimized because the force and synchronization sys

6、tems are independent.Lesson 34 Automatic Fixture Design5詞 匯 二、詞匯機(jī)械工程專業(yè)英語(yǔ)Batch-size 批量 special fixture 專用夾具 group fixture 成組夾具 modular fixture 組合夾具 highly flexible fixture 高柔性?shī)A具（隨行夾具）Lesson 34 Automatic Fixture Design6機(jī)械工程專業(yè)英語(yǔ)Traditional synchronous grippers for assembly equipment move parts to the g

7、ripper centre-line,assuring that the parts will be in a known position after they are picked from a conveyor or nest.課文分析三、課文分析用于裝配設(shè)備的傳統(tǒng)同步卡爪把零件移動(dòng)到夾具中心上，以確保零件從傳送機(jī)上或從備件盤上取出后置于已知位置上。 However, in some applications, forcing the part to the centre-line may damage either the part or equipment.然而在某些應(yīng)用場(chǎng)合，強(qiáng)制使

8、零件移動(dòng)到夾具的中心線上時(shí)，可能導(dǎo)致零件或設(shè)備的破壞。 Lesson 34 Automatic Fixture Design7機(jī)械工程專業(yè)英語(yǔ)When the part is delicate and a small collision can result in scrap, when its location is fixed by a machine spindle or mould, or when tolerance are tight, it is preferable to make a gripper comply with the position of the part,

9、rather than the other way around.課文分析當(dāng)該零件易損而且小小碰撞可能導(dǎo)致報(bào)廢時(shí)，或當(dāng)其位置是由機(jī)床主軸或模具來(lái)確定時(shí)，再或者當(dāng)公差要求很精密時(shí)，那寧可讓夾具去適應(yīng)零件位置，而不是相反 Lesson 34 Automatic Fixture Design8機(jī)械工程專業(yè)英語(yǔ)For this tasks, Zaytran Inc. Of Elyria, Ohio, has created the GPN series of non-synchronous, compliant grippers.課文分析為實(shí)現(xiàn)這些工作任務(wù)，美國(guó)俄亥俄州伊利里亞市的zaytran公司已

10、經(jīng)開發(fā)了GPN系列的非同步系列柔順性?shī)A具 Because the force and synchronization systems of the grippers are independent, the synchronization system can be replaced by a precision slide system without affecting gripper force.Gripper sizes range from 5lb grippingforce and 0.2 in. stroke to 400lb gripping force and 6 in. s

11、troke.因?yàn)閵A具的夾緊力和同步裝置是各自獨(dú)立的，用精密的滑移裝置來(lái)替換同步裝置而不影響夾具的作用力。夾具規(guī)格范圍是從0.2英寸行程、5磅夾緊力到6英寸行程、400磅夾緊力。 Lesson 34 Automatic Fixture Design9機(jī)械工程專業(yè)英語(yǔ)Production is characterized by batch-sizes becoming smaller and smaller and greater variety of products.課文分析現(xiàn)代生產(chǎn)的特征是批量變得越來(lái)越小而產(chǎn)品的品種規(guī)格越來(lái)越多。 Assembly, being the last produ

12、ction step, is particularly vulnerable to changes in schedules, batch-sizes, and product design. 因此，生產(chǎn)的最后階段-裝配因生產(chǎn)計(jì)劃、批量和產(chǎn)品設(shè)計(jì)的變更而顯得特別脆弱。 Lesson 34 Automatic Fixture Design10機(jī)械工程專業(yè)英語(yǔ)This situation is forcing many companies to put more effort into extensive rationalization and automation of assemble tha

13、t was previously the case.課文分析這種情形正迫使許多公司更多地致力于廣泛的合理化改革和前面提到過的那樣裝配自動(dòng)化。 Lesson 34 Automatic Fixture Design11機(jī)械工程專業(yè)英語(yǔ)課文分析Although the development of flexble fixtures fell quichky behind the development of flexible handling systems such as industrial robots,there are, nonetheless, promising attemptsto

14、increase the flexibility of fixtures.盡管柔性?shī)A具的發(fā)展很快落后于柔性輸送處理裝置的發(fā)展，如落后于工業(yè)機(jī)器人的發(fā)展，但仍然試圖增加夾具的柔順性。 Lesson 34 Automatic Fixture Design12機(jī)械工程專業(yè)英語(yǔ)The fact that fixtures are the essential product specific investment of a prouction system intensifies the economic necessity to make the fixture system more flexibl

15、e.課文分析事實(shí)上，夾具是重要的裝備生產(chǎn)裝置的專項(xiàng)投資就加強(qiáng)了使夾具更加柔性化在經(jīng)濟(jì)上的支持。 Fixture can be divided according to their flexibility into special fixtures, group fixtures, modular fixtures and highly flexible fixtures.根據(jù)夾具的柔性，可以分為：專用夾具、組合夾具、標(biāo)準(zhǔn)夾具和高柔性?shī)A具 Lesson 34 Automatic Fixture Design13機(jī)械工程專業(yè)英語(yǔ)Flexible fixtures are characterized

16、 by their high adaptability to different workpieces, and by low change-over time and expenditure.課文分析柔性?shī)A具是具有對(duì)不同工件的高適應(yīng)性、和裝卸工件時(shí)間短、低成本的特點(diǎn) Lesson 34 Automatic Fixture Design14機(jī)械工程專業(yè)英語(yǔ)課文分析Flexible fixtures with form variability are equipped with variable form elements (e.g., needle-cheek, multileaf, lame

17、lla-cheek), modular workpiece nonspecific holding or clamping-elments(e.g., pneumatic modular holding-fixtures and fixtures kits with noveable elements.)or with fictile and hardening media(e.g., particulate-fuidized-bed-fixtures and themal clamping-fixtures).結(jié)構(gòu)形式可變的柔性?shī)A具可裝備不同結(jié)構(gòu)的零件（例如：定位銷-支承板，多片式可調(diào)零件和

18、厚-薄支承板)，成組工件的非專用夾持或夾緊元件(例：氣動(dòng)組合夾具和帶有可調(diào)元件的夾具配套件)，或者裝備有陶瓷或淬硬的中介物質(zhì)(例如粒子流化床夾具和熱夾緊夾具)。 Lesson 34 Automatic Fixture Design15機(jī)械工程專業(yè)英語(yǔ)Independent of the flexibility of a fixture, there are several steps required to generate a fixture, in which a workpiece is fixed foe aproduction task.課文分析為完成某生產(chǎn)任務(wù)零件要在夾具中裝夾，有

19、幾個(gè)與夾具柔順性無(wú)關(guān)的生產(chǎn)夾具的步驟。 The first step is to define the necessary position of the workpiece in the fixture, based on the unmachined or base part, and the working features.首先根據(jù)不加工表面或基面和加工表面，確定工件在夾具中所需的位置， Lesson 34 Automatic Fixture Design16機(jī)械工程專業(yè)英語(yǔ)Following this, a combination of stability planes must b

20、e selected. These stability planes constitute the fixture configuration in which the workpiece is fixed in the defined position, all the forces or torques are compensated, and the necessary access to the working features is ensured.課文分析接著，必須選擇若干穩(wěn)定平面的組合，這些穩(wěn)定平面就構(gòu)成了工件被固定在夾具中確定位置上輪廓結(jié)構(gòu)，均衡所有各力和力矩，而且必須保證能接

21、近加工表面。 Lesson 34 Automatic Fixture Design17機(jī)械工程專業(yè)英語(yǔ)Finally, the necessary positions of moveable or modular fixture elements must be calculated, adjusted, or assembled, so that the workpiece is firmly fixed in the fixture.課文分析最后，必須計(jì)算、調(diào)整、裝配可移動(dòng)的或組合夾具元件的所需的位置，以便使工件牢牢地被夾緊在夾具中。 Through such a procedure, t

22、he planning and documentation of the configuration and assembly of fixture can be automated.依據(jù)這樣的程序，夾具的組裝和裝配可實(shí)現(xiàn)自動(dòng)化。 Lesson 34 Automatic Fixture Design18機(jī)械工程專業(yè)英語(yǔ)The configuration task is to generate a combination of stability planes, such that fixture forces in these planes will result in workpiece a

23、nd fixture stability.課文分析組合的任務(wù)就是要產(chǎn)生若于穩(wěn)定平面的組合，這樣在這些平面上的各夾緊力將使工件和夾具穩(wěn)定。 This task can be accomplished conventionally, interactively or in a nearly fully automated manner.這個(gè)任務(wù)可按常規(guī)、用人機(jī)對(duì)話或幾乎完全自動(dòng)化的方式來(lái)完成 Lesson 34 Automatic Fixture Design19機(jī)械工程專業(yè)英語(yǔ)The advantages of an interactive or automated configuation determination are systematic fixture design process, a reduction of necessary designers, a shortening of lead time and tetter match to t