【正文】 在以 “甩掉圖板 ”為目標(biāo)的計(jì)算機(jī)輔助繪圖與設(shè)計(jì)系統(tǒng)之上，應(yīng)用國外或國內(nèi)開發(fā)的一些計(jì)算機(jī)繪圖軟件，用計(jì)算機(jī)繪圖來代替?zhèn)鹘y(tǒng)的手工繪圖。 3． 參數(shù)化設(shè)計(jì)。 3． CAD 系統(tǒng)應(yīng)滿足并行設(shè)計(jì)的要求 產(chǎn)品可以容易地被分解為一些模塊，通過計(jì)算機(jī)網(wǎng)絡(luò)，組織分散在各地的產(chǎn)品設(shè)計(jì)人員分工進(jìn)行產(chǎn)品各 零部件的設(shè)計(jì)和制造，然后進(jìn)行組裝和集成。 7． 軟件系統(tǒng)要具有很好的可移植性和自組織性 在 CAD 系統(tǒng)中，用戶可以根據(jù)自己的需要隨時(shí)加入運(yùn)行文件和模塊，還可重新裝配各個(gè)模塊中的子模塊，或者按照自己的要求修改系統(tǒng)中的不足之處。 2． Pro/Engineer Pro/Engineer（簡稱 Pro/E）是由美國 PTC 公司推出的一套博大精深的三維CAD/CAM 參數(shù)化軟件系統(tǒng)，其內(nèi)容涵蓋了產(chǎn)品從概念設(shè)計(jì)、工業(yè)造型設(shè)計(jì)、三維模型設(shè)計(jì)、分析計(jì)算、動(dòng)態(tài)模擬與仿真、工程圖輸出，到生產(chǎn)加工成產(chǎn)品的全過程。包括車、銑、線切割等完善的加工方法。 CAXA 電子圖板還提供局部參數(shù)化設(shè)計(jì)和一個(gè)全開放的二維開發(fā)平臺(tái)。從下拉菜單或圖形菜單條中即可方便地獲取具體的 功能，更重要的是， PhotoWorks 不要求使用者有專門培訓(xùn)和背景知識(shí)就可以為設(shè)計(jì)或產(chǎn)品制作出精美的展示圖片。附加在幾何模型上的材質(zhì)屬性是可修改的，如顏色、反射和紋理等。光源的數(shù)量不受限制。背景可從標(biāo)準(zhǔn)格式的圖形文件輸入，這些格式是 JPEG、 TARGA、 TIFF、 BMP。 FeatureWorks 用于識(shí)別帶有長方形、圓錐形、圓柱形特征的零件和鈑金件最合適，可自動(dòng)識(shí)別的特征主要有：拉伸特征，特征的輪廓由直線、圓或圓弧構(gòu)成；圓柱形和圓錐形的旋轉(zhuǎn)特征；沿直線邊的倒角；沿直線邊和圓弧邊的等半徑倒圓。據(jù)調(diào)查 ,目前在機(jī)械行業(yè)中應(yīng)用比較廣泛的二維 CAD 繪圖軟件依 次是 :AutoCAD、 CAXA 電子圖板、開目 CAD、機(jī)械設(shè)計(jì)師 CAD、 PCCAD等。但實(shí)體造型技術(shù)的應(yīng)用還局限在單個(gè)零件的造型設(shè)計(jì)、自由曲面設(shè)計(jì)等方面。 CAD 技術(shù)在玉米聯(lián)合作業(yè)機(jī)械 設(shè)計(jì)中的 應(yīng)用 CAD 技術(shù)回顧與思考 通過 CAD 技術(shù)建立的機(jī)械模型，可對(duì)產(chǎn)品進(jìn)行運(yùn)動(dòng)機(jī)構(gòu)分析和機(jī)械特性校核 14 等，具有直觀、可交互操作等特點(diǎn)。地輪軸承座為截面旋轉(zhuǎn)生成 ,采用參數(shù)化設(shè)計(jì)，減少了反復(fù)修改時(shí)間，提高了設(shè)計(jì)效率及質(zhì)量。部件模型裝配過程是一個(gè)檢驗(yàn)零件過程，在模型裝配時(shí)可發(fā)現(xiàn)各種設(shè)計(jì)上的失誤，如零件干涉、欠自由度約束等，還可進(jìn)行結(jié)構(gòu)分析、運(yùn)動(dòng)機(jī)構(gòu)分析及質(zhì)量特性分析等。當(dāng)整機(jī)模型裝配好后， 即可對(duì)整機(jī)進(jìn)行運(yùn)動(dòng)機(jī)構(gòu)分析，查找設(shè)計(jì)不合理處，也可以就某一部分功能進(jìn)行仿真運(yùn)動(dòng)。 2． 繪制最能反映零件基本特征的幾何草圖，經(jīng)拉伸、旋轉(zhuǎn)生成三維實(shí)體。如動(dòng)臂本體由上板、下板、側(cè)板、加強(qiáng)筋板、連接耳板和軸套等十多個(gè)零件焊接而成，這些單個(gè)零件結(jié)構(gòu)一般比較簡單。 挖掘機(jī)外觀造型設(shè)計(jì)十分重要，是吸引用戶非常重要的一個(gè)方面。但柴油機(jī)外形復(fù)雜，可以采取簡化外形結(jié)構(gòu)建模，對(duì)可能涉及與 其它零部件交叉安裝的空間干涉部分進(jìn)行處理。 干涉檢查和運(yùn)動(dòng)仿真 在挖掘機(jī)新產(chǎn)品開發(fā)過程中，在投料加工之前利用計(jì)算機(jī)進(jìn)行裝配仿真，可以發(fā)現(xiàn)零、部件設(shè)計(jì)上的尺寸干涉和結(jié)構(gòu)不合理，及時(shí)糾正設(shè)計(jì)中的不足，避免實(shí)際制造中出現(xiàn)問題，造成浪費(fèi)和損失。例如：不少企業(yè)對(duì) CAD的認(rèn)識(shí)還僅停留在繪圖階段，從而使 CAD產(chǎn)生的效益尚未充分發(fā)揮； CAD/CAM軟件應(yīng)用人員參差不齊， CAD軟件不能得到高效率應(yīng)用；缺少既適合教學(xué)又滿足企業(yè)需求的軟件及教學(xué)平臺(tái)。s machinery manufacturing industry Today39。s economic engine, but also promote economic and social information and the basis of industry, science and technology innovation is more important carriers of the major employment and labor departments, is the basic guarantee for national security. But large manufacturing country does not mean that manufacturing power, because although the total amount of 20% of the United States, but its labor productivity is only 4%, and global manufacturing power is only 5% of 28 China has not a manufacturing enterprise into the World Top 50 people 。s CNC technology applications will be created hundreds of thousands of operators, programmers and maintenance staff. 2 .Chinese machinery manufacturing and the trend of development of the CAD / CAM technology requirements How China as soon as possible by the large manufacturing country to a manufacturing power? We have to think about. Machinery manufacturing industry is the development direction of what the machinery manufacturing and provide strong technical support plays a key role in the CAD / CAM technology development should be guided by what principle? Beginning of the 21st century mechanical manufacturing, the development of the overall trend: Flexible, Agile, intelligence, and information technology (work) the same. Information industry will bee the dominant industry, machinery manufacturing industry will also be informationled, and the use of advanced manufacturing, and advanced manufacturing technology, advanced management anizations new machinery manufacturing. Including: flexible is the technique and equipment and technology suitable for the production line to the needs of a variety of products, can be suitable for rapid replacement technology, the need for replacement products. Ling Jie is the production of readytomarket reduction for the shortest time, so that the machinery factory mechanism to be flexible. Flexible intelligent automation 29 is an important ponent of the Flexible Automation is a new development and extension, intelligent promote flexible, which make the production system is better judgement and ability to adapt. Information is no longer a mechanical manufacturing material and energy aid from the power of information to produce value, but through the use of information from the strength of material and energy to produce value. Therefore, the information industry, and intellectual industry will bee the leading industries of the munity. Furthermore, manufacturing technology also toward ultraprecision machining, micromachinery manufacturing, such as highspeed cutting direction. Ultraprecision processing technology, micromachining, microEDM EDM, plasma processing, laser processing, ion beam processing, and electron beam processing, and highspeed processing technology to achieve for the rapid increase production efficiency has laid a good foundation. At the same time, manufacturing technology are constantly on the prehensive utilization of high technology, the need to Engineering Mathematics, laser science, microelectronics technology, puter technology, control theory, biology, material science, management science, information science, the humanities and scientific knowledge Comprehensive Utilization. These subjects changing the face of manufacturing machinery, and machinery manufacturing technology for the development of these disciplines in turn provides a new tool to effectively promote the further development of these fields. CAD / CAM technology is the use of a puter to help people plete product design (Design) and manufacturing (Made) of the new technology, which is puter technology in the production of integrated application ponents for a new leap. Including the establishment of CAD geometry model, engineering analysis, product analysis, dynamic simulation, automatic mapping。 countries 36 per cent of the total tax revenue, the Financial to the nearly 50 percent, and foreign exchange earnings of 75 per cent, industrial new jobs in the manufacturing sector from 90 per cent to create the manufacturing sector absorbed nearly half of the urban employment and rural surplus labor。在這些前提下，我國 CAD/CAM產(chǎn)業(yè)只要緊跟時(shí)代潮流，跟蹤國際最新動(dòng)態(tài)，遵守國際規(guī)范，形成自己獨(dú) 特的優(yōu)勢(shì)，并且立足國內(nèi)、結(jié)合國情、面向國內(nèi)經(jīng)濟(jì)建設(shè)的需要，一定能夠開發(fā)出有