計算機在模具設(shè)計中的應(yīng)用外文翻譯

1、<p><b>　　中文2913字</b></p><p>　　畢業(yè)設(shè)計(論文)外文資料翻譯</p><p>　　學(xué) 院(系)： </p><p>　　專 業(yè)： </p><p>　　姓 名：

2、 </p><p>　　學(xué) 號： </p><p>　　外文出處：Michael Thielen.Plastics Pocket </p><p>　　Power Series,2001.

3、 </p><p>　　附 件： 1.外文資料翻譯譯文；2.外文原文。 </p><p>　　注：請將該封面與附件裝訂成冊。</p><p>　　附件1：外文資料翻譯譯文</p><p>　　計算機在模具設(shè)計中的應(yīng)用</p><p>　　CAD一詞有時用來指計算機輔

4、助設(shè)計，有時用來指計算機輔助繪圖，實際上，它既可表達(dá)上述兩個概念之一，也可同時兼具這兩個概念，設(shè)計人員有時會既用它設(shè)計又用它繪圖。</p><p>　　CAD計算機輔助設(shè)計是指用計算機及外設(shè)簡化設(shè)計過程、提高設(shè)計質(zhì)量。CAD 計算機繪圖是指用計算機和外設(shè)（如打印機、數(shù)字化儀）來產(chǎn)生設(shè)計過程的文件和圖樣,包括草圖、加工圖、零件清單及設(shè)計計算。</p><p>　　無論是計算機輔助設(shè)計還是輔助

5、繪圖，一套CAD 系統(tǒng)基本由三個部分組成：硬件，軟件和用戶。典型CAD 系統(tǒng)的硬件部分包括處理器、顯示器、鍵盤、數(shù)字化儀和繪圖儀；軟件部分包括能實現(xiàn)設(shè)計和繪圖功能的程序；用戶指的是用這些軟、硬件簡化設(shè)計過程、提高設(shè)計質(zhì)峨的設(shè)計人員。</p><p>　　圖形顯示是第一步，從而可將設(shè)計與計算機真正結(jié)合起來，接下來是用繪圖儀畫出圖形。隨著20 世紀(jì)60 年代早期數(shù)字化平板儀的發(fā)明，我們今天所知的CAD 硬件開始成型，

6、很快計算機繪圖軟件隨之得以發(fā)展。</p><p>　　早期的CAD 系統(tǒng)龐大、笨重且昂貴．因為太貴了，只有大公司才用得起．在20 世紀(jì)60 年代末，CAD 被認(rèn)為有在模具設(shè)計中應(yīng)用的潛力和意義但不實用的革新。但是，隨著20 世紀(jì)70 年代硅芯片的引入，計算機開始在圖形設(shè)計領(lǐng)域發(fā)揮作用。</p><p>　　硅晶片上的集成電路使得組裝起來的計算機與電視機一樣大?。?。這種“迷你”小型機具有大型

7、計算機的全部功能，但卻小得多也相當(dāng)便宜，很快又出現(xiàn)了更小的被稱為微機的計算機。</p><p>　　20 世紀(jì)70 年代CAD 軟硬件技術(shù)有了長足的發(fā)展，以至于在20 世紀(jì)80 年代初，研發(fā)與銷售CAD 系統(tǒng)已成為一個飛速增長的產(chǎn)業(yè)。同時CAD 已由最初的新穎但不實用變成為今天的一項重要發(fā)明，到了1980 年，已有從微機、小型機到大型計算機用的多種CAD 系統(tǒng)。</p><p>　　計算機

8、集成制造CIM 指與一個目標(biāo)產(chǎn)品（這里以模具為例）設(shè)計和制造過程相關(guān)的所有部門的電子數(shù)據(jù)處理EDP 的集成，就信息技術(shù)而言，是聯(lián)系計算機輔助設(shè)計CAD 、計算機輔助生產(chǎn)CAP 、計算機輔助制造CAM 、計算機輔助質(zhì)量保證CAQ 和產(chǎn)品計劃進度安排PPS （如圖1 ）的紐帶。這就意味著和產(chǎn)品有關(guān)的所有信息交換是連續(xù)無間斷的，由集成電子數(shù)據(jù)處理計算機提供通訊鏈接。在CIM 結(jié)構(gòu)模塊中，CAM 占主導(dǎo)地位，借助CAM , 可將用CAD 研發(fā)的

9、理論產(chǎn)品轉(zhuǎn)化為真實有用的模具。</p><p>　　圖1 實現(xiàn)CIM系統(tǒng)所用的CAD,CAP,CAM,CAQ和PPS</p><p>　　A ．計算機在注塑模具加工中的應(yīng)用</p><p>　　CAM 的目標(biāo)是：盡可能不用其他中間步驟（如不需要模型復(fù)制）就可生產(chǎn)出模具部件，也就是從計算機工作站開始加工操作。</p><p>　　實施CIM

10、 意義上的CAM 所需的先決條件包括：CAD 、通訊接口、生產(chǎn)操作中轉(zhuǎn)換產(chǎn)品信息所需的軟件程序及硬件設(shè)備（如圖2 所示）。</p><p>　　B . CAD 在制品圖繪制中的應(yīng)用</p><p>　　CAD 是指在顯示器（電腦屏幕）上進行計算機輔助設(shè)計。先是設(shè)計人員（一般是產(chǎn)品設(shè)計人員）用計算機軟件輔助繪制產(chǎn)品圖，然后對產(chǎn)品，主要是其可視表面進行修改，直至其功能和外觀設(shè)計都滿足客戶要求為

11、止。</p><p>　　圖2 模具生產(chǎn)工序</p><p>　　對于那些外形決定產(chǎn)品性能的塑料制品，如汽車保險杠，產(chǎn)品設(shè)計并不僅限在屏幕上進行，其研制從投標(biāo)過程就開始了，競標(biāo)的設(shè)計者們先把各自準(zhǔn)備好的石膏模型展示給汽車制造的管理部門，由其從中選擇一個，接著要對所選的石膏模型測取各種型值點，然后把這些數(shù)據(jù)傳到CAD 系統(tǒng)中，至此，產(chǎn)品設(shè)計人員才可用這些數(shù)據(jù)在屏幕上開始設(shè)計。借助于軟件程

12、序，將離散的點云擬合成3 一D 曲面，尖角光滑過渡，反復(fù)擬合修整直至得到滿意的結(jié)果。</p><p>　　接下來在屏幕上把產(chǎn)品的曲面數(shù)據(jù)經(jīng)由加工程序轉(zhuǎn)換成3 一D 原始模型，這樣生成的原始模型就可置人表示整體汽車的立體模型中了。在該設(shè)計階段，最初負(fù)責(zé)石膏模型設(shè)計的人員通常不會對模型做大的改動，做完最后的修改，設(shè)計才被認(rèn)可核準(zhǔn)。</p><p>　　此時的模型已完全數(shù)字化，也就是說，探針掃描

13、原始模型表面，（獲得的）數(shù)據(jù)被電子化儲存。一旦生成這種形式的數(shù)據(jù)，產(chǎn)品設(shè)計就完成了。此時計算機軟件可用計算機語言描述產(chǎn)品，可對其進行修改、復(fù)制，如果有合適的接口還可方便地與其他計算機系統(tǒng)進行數(shù)據(jù)交換。</p><p><b>　　C ．接口</b></p><p>　　產(chǎn)品設(shè)計一般由模具制造商的客戶承擔(dān)，如汽車生產(chǎn)廠商要進行產(chǎn)品的計算機輔助設(shè)計，負(fù)責(zé)模具制造的廠商要能

14、接收其數(shù)據(jù)．這就要求二者使用相同的計算機系統(tǒng)，或者所用機器接口要相兼容，以便數(shù)據(jù)從客戶端（如汽車生產(chǎn)商）傳送給模具制造商，并且要保證數(shù)據(jù)能在汽車生產(chǎn)商的CAD 部門內(nèi)順利交換。</p><p>　　接口按操作規(guī)則可分為兩大類：一類是直接偶合接口（系統(tǒng)特定接口）；另一類是帶有前、后里處理單元的獨立于系統(tǒng)的接口。</p><p>　　直接偶合接口：原則上講，期望一個計算機系統(tǒng)能夠提供和另一個計

15、算機系統(tǒng)直接的數(shù)據(jù)交換必須有兩個程序：其中一個從另外一臺計算機系統(tǒng)讀數(shù)據(jù)并轉(zhuǎn)化為自己的系統(tǒng)格式，另一個用來轉(zhuǎn)換自己的數(shù)據(jù)并寫成其他電腦識別的格式，這就是直接偶合。</p><p>　　獨立系統(tǒng)接口：市場上已經(jīng)有獨立于系統(tǒng)的接口，有了這些接口，CAD / CAM 軟件系統(tǒng)和系統(tǒng)版本基本不依賴硬件及操作系統(tǒng)，這種接口也需要兩個程序：</p><p>　?、?寫程序能把其他系統(tǒng)的數(shù)據(jù)轉(zhuǎn)換成與系統(tǒng)

16、無關(guān)的標(biāo)準(zhǔn)形式，并以文件形式記錄下來（即前置處理程序）。</p><p>　?、?讀程序能讀取與系統(tǒng)無關(guān)的標(biāo)準(zhǔn)文件，并轉(zhuǎn)換為用戶自身的格式（即后置處理程序）。利用這些程序，用戶系統(tǒng)就能將數(shù)據(jù)傳送到支持該接口標(biāo)準(zhǔn)的其他任何計算機系統(tǒng)中，常用的與系統(tǒng)無關(guān)的接口有以下幾種：</p><p>　　VDAFS ，這種接口能精確轉(zhuǎn)換曲線和曲面信息（三維幾何）。但尺寸、文字、視圖及其他二維圖素?zé)o法通過V

17、DAFS ( 1986 DIN 標(biāo)準(zhǔn)VDA / VDMA 66301 ）進行交換，要在德國和歐洲使用．</p><p>　　IGES 是最早使用的主要用于二維數(shù)據(jù)交換的接口之一，較新的IGES 版本也可用來轉(zhuǎn)換三維信息。主要在美國使用。</p><p>　　SET 接口主要用于汽車和飛機工業(yè)上，只在法國使用。</p><p>　　盡管接口技術(shù)在不斷發(fā)展，也經(jīng)過了15

18、 年的應(yīng)用，數(shù)據(jù)丟失現(xiàn)象依然普遍存在。當(dāng)數(shù)據(jù)傳送出現(xiàn)這種情況時，圖紙就會再次作為傳遞信息的媒介被使用。</p><p>　　當(dāng)前努力的目標(biāo)是將上述標(biāo)準(zhǔn)結(jié)合起來．形成一個通用系統(tǒng)（STEP ) ，這種系統(tǒng)可以兼容各種接口技術(shù)，從而實現(xiàn)所有產(chǎn)品數(shù)據(jù)的無縫轉(zhuǎn)換連接。目前，STEP 仍處于研究階段。</p><p>　　接口還為單個計算機系統(tǒng)提供通訊手段，如果沒有正確的接口配籠，極有可能由于選錯軟

19、件造成同一公司內(nèi)的CAD 和CAM 部門之間沒辦法通訊，這樣會造成接口處數(shù)據(jù)文件丟失，導(dǎo)致產(chǎn)品表征不完全。數(shù)據(jù)傳輸必定被完全終止，或者丟失的數(shù)據(jù)必須進人合適的計算機系統(tǒng)重新獲得。</p><p><b>　　D ．軟件</b></p><p>　　隨著數(shù)據(jù)交換技術(shù)的興起，市場上出現(xiàn)了一大批軟件供應(yīng)商，使得在一家公司選擇應(yīng)用軟件差不多同彩票中獎一樣困難。然而，在隨后的發(fā)

20、展中，只有少數(shù)軟件系統(tǒng)可以通過合適的接婦建立自身和其他軟件系統(tǒng)的聯(lián)系，軟件功能需求的滿足由最終用戶的目標(biāo)決定。供應(yīng)商提供的軟件包或多或少地?fù)碛杏脩粲押玫慕缑?，有助于幫助用戶完成特定的任?wù)，如產(chǎn)品設(shè)計（CAD ）、生產(chǎn)規(guī)劃（CAP ）、加工程序編制（CAM ）等。</p><p>　　知名的機械設(shè)計軟件供應(yīng)商有Altium , Autodesk , Cadkey , Hewlett 一Packard , Inter

21、g - raph , McS 和ziegler 一Informatics 。很明顯選擇哪種軟件不能僅看其可以實現(xiàn)何種功能，還要重點考慮圖形的表達(dá)、能否或該不該顯示二維或三維圖形、對硬件有無限制，可能用到的接口及軟件價格等因素。</p><p>　　E . CAD 模其設(shè)計</p><p>　　一旦用戶將設(shè)計好的制品通過合適的接口傳給模具制造商，模具設(shè)計人員就可依據(jù)制品設(shè)計模具。設(shè)計人員決定

22、模具尺寸、需不需要滑動部件（滑塊、推桿）、冷卻管道的布局和澆口位里等與制品幾何形狀相關(guān)的所有因素。模具設(shè)計的所有細(xì)節(jié)都被存儲在計算機中，可隨時被生產(chǎn)部門或計劃調(diào)度部門調(diào)用。</p><p>　　附件2：外文原文（復(fù)印件）</p><p>　　The computer in die design</p><p>　　The term CAD is alternatel

23、y used to mean computer aided desing and computer dided drafting.Actually it can mean either one or both of these concepts,and the tool designed will have ccasion to in both forms.</p><p>　　CAD computer dide

24、d design means using the computer and peripheral devices t simplify and enhance the design process.CAD computer aided drafting means using the computer and peripheral devices to produce the documentation and graphics for

25、 the design process.This documentation usually includes such things as preliminary drawings,working drawings,parts lists,and design calculations.</p><p>　　A CAD system,whether taken to mean computer aided de

26、sign system or computer aided drafting system,consists of three basic components:hardware,software,users.The hardware compoents of a typical CAD system include a processor,a system display,a keyboard,a disgitizer,and a

27、piotter.The software component of a CAD system consists of the programs which allow it to perform desgn and drafting functions.The user is the tool designer who user the hardware and software to simplify and enhance the

28、design p</p><p>　　Graphics displays represented the frist real step toward bringing the worlds of tool design dad the computer together.The plotters depicted in Figure,represented the next step.With the adve

29、nt of the digitizing tabiet in the early 1960’s,CAD hardware as we know it today began to takeshape.The development of computer graphics software follow soon after these hardware developments.</p><p>　　Early

30、 cad system were large,cumbersome,and expensive,in fact that only the largest companies could afford them.During the late 1960’s CADwas looked on as an interesting,but impractical novelty that had only limited potential

31、in tool design applications.However,with the introduction of the silicon chip during the 1970’s,computers began to take their place in the world of tool design.</p><p>　　Intergratedcircuits on silion chips a

32、llowed full scale computed to be packaged in small consoles no larger than Tvsets.these”minicomputers”had dll of the characteristics of full scale computers,but they were smaller and considerably less expensive.Even smal

33、ler computers called microcomputers followed soon after.</p><p>　　The 1970’s saw continued advances in CAD hardware and software technology.So much that by the beginning of the advance in CAD system had beco

34、me a growth industry.Also,CAD has been transformed form its status of impractical novelty to its new status s one of the most important inventions to date.By 1980,numerous CAD systems were available ranging in size form

35、microcomputer systems to large minicomputer and mainframe system.</p><p>　　Computerintegrated manufacturing (CIM) represents integration of electronic data processing (EDP) into all departments associated wi

36、th planning and production of an object (in this case,a mold):the linking of computeraided design (CAD),Computeraided production (CAP),conputeraided manufacturing (CAM),computeraided qualityassurance (CAQ)，production pla

37、nning and schedulng (PPS)(see Fig 1) in terms of information technolgy.This means uninterrupted exchange of all information pertinent to a product.T</p><p>　　Fig.1 Linking of CAD.CAP.CAM.CAQand PPS to imple

38、ment CIM</p><p>　　A.Use of Comoutes for Machining of an Injection Mold</p><p>　　The objective of CAM is to produce,f possible,sections of a mold without intermediate steps (e.g..,elimination of

39、copy patterns),i.e.,by initidting machining operations from the computer workstation.</p><p>　　Prerequisites for CAM in the sense of CIM include CAD,the communications interface,and appropriate software and

40、hardware for converting product information in the required production operations (see sequence diagram,Fig2).</p><p>　　Fig.2 Mold Producting Sequence</p><p>　　B.CAD for Part Construction</p

41、><p>　　CAD means computeraided design on a monitor.The designer,initially the part designer,draw a product with the aid of the computer software.The part,primarily its visible surface,is modified until both fun

42、ction and appearance (design) of the part satisfy the requirements.</p><p>　　For plasic parts with character determining product properties,e.g. automobile bumper fascias,product design does not occur on the

43、 creen only.Product development takes place in a kink of bidding proces in which several stylists (designer)frist prepare plaster patterns,which are then presented to the management of the automotive manufacture in a com

44、petition.The management makes a selection and agrees on a design model.Next,measurements are taken at various points on the piaster pattern of the sel</p><p>　　In a subsequent step,the work on the screen is

45、converted into a 3D master pattern through creation of a machining program form the surface data of the part.The master partern thus produced can now be attached to a cubing model that representa the entire automobile.At

46、 this phase in the development of the product the stylist,who was originally responsible for the plastr pattern,will generally allow minor changes to be made.After hese final modifications are made,the design is approved

47、.</p><p>　　The approved master pattern is now completely digitized,i.e.,a stylus scans the surface of the pattern,and part designer can complete the work.The software now describes the product in computer la

48、nguage.The design can be modified,duplicated,and exchanged freely with other computer systems as long as suitable interfaces are available.</p><p>　　C.Interfaces</p><p>　　Responsibility for part

49、 design is assumed almost entirely by the cutomer of the moldmakeer.A computer aide part design that originates form the customer (e.g.,automotive manufacturer) must be accessible to be company that will produce the mold

50、.these require either the same computer system or a compatible computer interface so that the data can be transferred from the customer (automotive manufacturer) to the mold maker.It must also be possible to exchange da

51、ta among the CAD department of the au</p><p>　　Interfaces can be grouped into two basic types (operating principle):frist,interfaces based on the direct couple principle (system specific interface);second,he

52、 system independent interface with paeand post paocesing units.</p><p>　　Direct Coupler Interface:In principle,a comouter system that is expected to priovide direct data exchang with any other computer syste

53、m must have tow programs:one program that reads the data from the other computer and transfers it into own system,and another program that converts its data and writes it in the data frmat of the other computer.Such an i

54、nterface is called a direct coupler.</p><p>　　System Independent Interface:Interfaces that are system independent have became established in the market.With these,CAD\CAM system and system versions are essen

55、tially independent of the hardware and operating system.Such an interface must contain two programs:</p><p>　?、貯 write program that converts elements from the other computer system to the system-independent

56、standard and writes them to a file (preprocessing);</p><p>　?、贏 read program that reads the data, which are in a system-independent format, and converts theminto the computer users own format (postporcessing

57、).</p><p>　　By means of these programs, the users own system can transfer data to all other computer systems that support this interface standard. The following system-independent interfaces are in use:</

58、p><p>　　VDAFS This interface readily converts representations of curves and surface without loss of accuracy (3-D geometries). Dimensions, text, views, and other 2-D drawing elements cannot be exchanged via VDA

59、FS (1986 DIN Standard VDA/VDMA 66301). Use: Germany and Europe.</p><p>　　IGES This is one of the first useful data interfaces for exchange primarily 2-D formats. With more recent IGES versions, it is also po

60、ssible to exchange 3-D information. Use:USA.</p><p>　　SET This interface is important in the automotive and aircraft industries (Airbus) in France but isnot used outside France.</p><p>　　Despite

61、 the continued development of interface systems and more than 15 years of application, data loss is still not uncommon. In many cases, such difficulties during data transfer mean that the drawing (part drawing) once agai

62、n becomes the medium by which information (data) must be conveyed. Current efforts aim to combine the above¡ªmentioned standards into a national system (Standard for the Exchanged of Product Model data, or