【正文】 second,he system independent interface with paeand post paocesing units. Direct Coupler Interface:In principle,a outer system that is expected to priovide direct data exchang with any other puter system must have tow programs:one program that reads the data from the other puter and transfers it into own system,and another program that converts its data and writes it in the data frmat of the other an interface is called a direct coupler. System Independent Interface:Interfaces that are system independent have became established in the these,CAD\CAM system and system versions are essentially independent of the hardware and operating an interface must contain two programs: ① A write program that converts elements from the other puter system to the systemindependent standard and writes them to a file (preprocessing)。然而，在隨后的發(fā)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決定。 SET 接口主要用于汽車和飛機工業(yè)上，只在法國使用。 C ．接口 產(chǎn)品設(shè)計一般由模具制造商的客戶承擔，如汽車生產(chǎn)廠商要進行產(chǎn)品的計算機輔助設(shè)計，負責模具制造的廠商要能接收其數(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。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止。 20 世紀 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 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)。 無論是計算機輔助設(shè)計還是輔助繪圖，一套 CAD 系統(tǒng)基本由三個部分組成：硬件，軟件和用戶。 附件 1：外文資料翻譯譯文 計算機在模具設(shè)計中的應(yīng)用 CAD 一詞有時用來指計算機輔助設(shè)計，有時用來指計算機輔助繪圖，實際上 ，它既可表達上述兩個概念之一，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。但是，隨著 20 世紀 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。 圖 1 實現(xiàn) CIM系統(tǒng)所用的 CAD,CAP,CAM,CAQ 和 PPS A ．計算機在注塑模具加工中的應(yīng)用 CAM 的目標是 ：盡可能不用其他中間步驟（如不需要模型復制）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。 此時的模型已完全數(shù)字化，也就是說，探針掃描原始模型表面，（獲得的）數(shù)據(jù)被電子化儲存。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準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： VDAFS ，這種接口能精確轉(zhuǎn)換曲線和曲面信息（三維幾何）。 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，導致產(chǎn)品表征不完全。設(shè)計人員決定模具尺寸、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。mentioned standards into a national system (Standard for the Exchanged of Product Model data, or STEP) and in this way unite development of the various interfaces in order to facilitate the seamless transfer of all productdefining data. At present, STEP is still in the development phase. The interface also provides for munication between the individual puter systems. It is quite possible to have no connection between, for instance, the CAD and CAM departments within the same pany because the wrong software was selected without the correct interface configuration. Data files can be lost at the:iiiterface in thus way so that the product is represented inpletely. In this case, data transfer must be terminated pletely or the lost information must be reentered into the appopriate puter system. D. Software With the introduction of data processing, a flood of software suppliers appeared on the market so that the selection of software for use within a pany almost began to resemble a lottery. In the course of further development, however, only a few sy