【正文】
擇是銑削加工的加工工藝中的重要內(nèi)容之一,它不僅影響加工效率,而且會(huì)直接影響加工質(zhì)量。對(duì)于本次課題所涉及的毛坯及模型表面來(lái)說(shuō),粗、精加工分別選用直徑為10mm的立銑刀和直徑為8mm的球頭銑刀。3.把準(zhǔn)備好的毛坯裝夾到數(shù)控銑床上。在數(shù)控加工過(guò)程中,為了避免毛坯發(fā)生任何移動(dòng),毛坯必須可靠定位和夾緊。也就是說(shuō),當(dāng)承受切削力時(shí),毛坯不能產(chǎn)生任何移動(dòng)或竄動(dòng)現(xiàn)象。而且在數(shù)控加工中,不可能一直檢測(cè)零件尺寸,因此任何移動(dòng)即便是很小的移動(dòng),都會(huì)影響零件的尺寸精度。所以在裝夾毛坯時(shí),要根據(jù)合適的力度和位置進(jìn)行裝夾。一次裝夾,完成汽車(chē)車(chē)身模型的粗加工、精加工。4.對(duì)數(shù)控銑床上進(jìn)行對(duì)刀操作。用機(jī)床控制面板上回參考點(diǎn)鍵啟動(dòng)“回參考點(diǎn)”,在“回參考點(diǎn)”窗口中顯示該坐標(biāo)軸是否必須回參考點(diǎn)?!啊稹北硎咀鴺?biāo)軸未回參考點(diǎn)。分別按+X、+Y、+Z坐標(biāo)軸方向鍵使機(jī)床回零,如果選擇了錯(cuò)誤的回參考點(diǎn)方向,則不會(huì)產(chǎn)生運(yùn)動(dòng)。需要注意的是“回參考點(diǎn)”只有在JOG方式下才可以進(jìn)行。而且必須給每個(gè)坐標(biāo)軸逐一回參考點(diǎn)。為安全起見(jiàn),一般先回Z方向。對(duì)刀點(diǎn)是數(shù)控加工時(shí)刀具相對(duì)零件運(yùn)動(dòng)的起點(diǎn),也是程序的起點(diǎn)。為了便于坐標(biāo)的計(jì)算,對(duì)刀點(diǎn)最好選在該坐標(biāo)系的原點(diǎn)上。根據(jù)設(shè)定的加工坐標(biāo)系分別對(duì)X、Y、Z軸進(jìn)行測(cè)量并計(jì)算。5.在CIMCO EDIT LITE ,并對(duì)該程序進(jìn)行修改使該程序開(kāi)頭必須改成系統(tǒng)能接受的格式,開(kāi)頭格式如下:%_N_H_MPF。$PATH=/_N_MPF_DIR 以上兩行從格式上來(lái)說(shuō)不允許有間隔。繼續(xù)添加G90、G1G6G5GG49等指令,使程序和該機(jī)床相關(guān)聯(lián)的同時(shí)能夠保證加工的正確性。圖52“DNC SETUP”傳輸數(shù)據(jù)設(shè)置在該軟件的“transmission”中選擇“DNC setup”選項(xiàng),如圖52所示進(jìn)行相關(guān)設(shè)置。點(diǎn)擊圖52中的“setup”,對(duì)照“port information”的信息在圖53里一一進(jìn)行設(shè)置。 圖53 “machine 2”的相關(guān)設(shè)置6.在CIMCO EDIT LITE “transmission”菜單中選擇“send” ,把修改好的程序傳輸?shù)姐姶采先?,在傳輸過(guò)程中由于程序比較長(zhǎng),系統(tǒng)的內(nèi)存有限,無(wú)法裝載程序用CNC來(lái)加工。按下“POSITION”鍵后按“AUTO”鍵,選擇“外部程序”后,這個(gè)外部程序就可以由接口輸入控制系統(tǒng),且一邊傳送一邊執(zhí)行加工程序,這種方法也稱(chēng)為DNC直接數(shù)控加工。【11】7.粗加工完畢后,打開(kāi)精加工程序,并對(duì)其進(jìn)行修改,方法如步驟5。8.把修改好的程傳輸?shù)綌?shù)控銑床上,開(kāi)始汽車(chē)車(chē)身模型的精加工。9.精加工完畢后,關(guān)掉機(jī)床。使刀具退回到安全位置后取下汽車(chē)車(chē)身模型。實(shí)體如圖54所示。圖54 汽車(chē)車(chē)身模型 數(shù)控加工總結(jié) 在實(shí)際的數(shù)控加工中,毛坯的裝夾和對(duì)刀操作直接影響到零件的加工精度,因此,毛坯必須可靠定位和夾緊,在數(shù)控加工過(guò)程中,毛坯不能發(fā)生任何移動(dòng)。而對(duì)刀操作更應(yīng)該謹(jǐn)慎進(jìn)行以確保加工質(zhì)量。第六章 結(jié) 論 論文總結(jié)通過(guò)近四個(gè)月的努力,本次畢業(yè)設(shè)計(jì)(基于UG奧迪汽車(chē)車(chē)身的曲面設(shè)計(jì)與加工)已全部順利完成。畢業(yè)設(shè)計(jì)是大學(xué)生大學(xué)四年學(xué)習(xí)的一個(gè)總結(jié),在這次設(shè)計(jì)過(guò)程中我不僅運(yùn)用了四年中學(xué)到的很多相關(guān)知識(shí),同時(shí)也學(xué)會(huì)了許多平時(shí)學(xué)習(xí)過(guò)程中沒(méi)有學(xué)到的知識(shí)。相關(guān)工作總結(jié)如下:一、主要工作及結(jié)論(1) 將光柵圖導(dǎo)入U(xiǎn)G軟件中,并依照此圖進(jìn)行三維建模,對(duì)汽車(chē)車(chē)身的外形具體采用曲面建模的方式。(2) 建模成功后對(duì)汽車(chē)外形進(jìn)行局部調(diào)整使之有更好的可加工性,利用UG軟件中CAM功能,對(duì)汽車(chē)車(chē)身模型進(jìn)行虛擬加工,并通過(guò)后處理功能生成數(shù)控加工程序。(3) 將仿真后得到的數(shù)控加工程序通過(guò)數(shù)據(jù)線傳送到數(shù)控機(jī)床系統(tǒng),進(jìn)行汽車(chē)車(chē)身模型的數(shù)控加工。二、存在的問(wèn)題(1) 因加工設(shè)備的局限性,對(duì)設(shè)計(jì)出的汽車(chē)車(chē)身外形做了相關(guān)的參數(shù)修改,使得該模型符合加工設(shè)備的可加工性,因此加工出的實(shí)際模型并沒(méi)有設(shè)計(jì)出的模型外形曲面優(yōu)美。(2) 由于缺少對(duì)數(shù)控機(jī)床的實(shí)際操作經(jīng)驗(yàn),在對(duì)刀方面存在一定的誤差,加工出的模型也與理想情況有所偏差。 感想本次畢業(yè)設(shè)計(jì)運(yùn)用了當(dāng)今世界上最先進(jìn)的CAD/CAM軟件之一——UG NX。在以前的學(xué)習(xí)過(guò)程中并沒(méi)有接觸過(guò)該軟件,因此,對(duì)于我來(lái)說(shuō)這是一個(gè)全新的領(lǐng)域,這也給本次設(shè)計(jì)帶來(lái)了一定的難度和挑戰(zhàn)性。通過(guò)本次畢業(yè)設(shè)計(jì),我熟練地掌握UG NX軟件的各種強(qiáng)大的功能以及這些功能在汽車(chē)車(chē)身的曲面設(shè)計(jì)和加工中的應(yīng)用。通過(guò)對(duì)奧迪汽車(chē)車(chē)身模型的造型設(shè)計(jì)和三維數(shù)據(jù)測(cè)量,培養(yǎng)了我獨(dú)立思考和自主設(shè)計(jì)的能力,并使得自學(xué)和綜合分析能力有所提高。最后對(duì)設(shè)計(jì)出的汽車(chē)車(chē)身模型在加工中心上進(jìn)行數(shù)控加工,更是做到了將基礎(chǔ)與專(zhuān)業(yè)、理論與實(shí)踐相結(jié)合,在掌握數(shù)控加工中心操作方法的同時(shí)使自己的動(dòng)手能力有了進(jìn)一步的提高。 致 謝本設(shè)計(jì)(基于UG奧迪汽車(chē)車(chē)身的曲面設(shè)計(jì)與加工)的建模和數(shù)控加工工作是在我的導(dǎo)師(實(shí)驗(yàn)師)的精心指導(dǎo)和悉心關(guān)懷下完成的,在我的學(xué)業(yè)和設(shè)計(jì)工作中無(wú)不傾注著導(dǎo)師辛勤的汗水和心血。導(dǎo)師的嚴(yán)謹(jǐn)治學(xué)態(tài)度、淵博的知識(shí)、無(wú)私的奉獻(xiàn)精神使我深受的啟迪。從尊敬的導(dǎo)師身上,我不僅學(xué)到了扎實(shí)、寬廣的專(zhuān)業(yè)知識(shí),也學(xué)到了做人的道理。最為重要的是學(xué)會(huì)了學(xué)習(xí)和思考的方法,以及面對(duì)問(wèn)題的態(tài)度,嚴(yán)謹(jǐn)?shù)淖黠L(fēng),不僅在學(xué)習(xí)生活,做人的道理上都深受感染。在此我要向我的導(dǎo)師致以最衷心的感謝和深深的敬意。在我的畢業(yè)設(shè)計(jì)(論文)撰寫(xiě)過(guò)程中,老師等提出了寶貴的意見(jiàn)和建議,在此我也向他們表示深深的感謝。在多年的學(xué)習(xí)生活中,還得到了許多學(xué)院領(lǐng)導(dǎo)、系(數(shù)控教研室)領(lǐng)導(dǎo)和老師的熱情關(guān)心和幫助。在日常學(xué)習(xí)和生活中我也要感謝我的父母和親人,他們?cè)谖业膶W(xué)業(yè)中給了我莫大的鼓勵(lì)、關(guān)愛(ài)和支持。最后,向所有關(guān)心和幫助過(guò)我的領(lǐng)導(dǎo)、老師、同學(xué)和朋友表示由衷的謝意!衷心地感謝在百忙之中評(píng)閱我的設(shè)計(jì)(論文)和參加答辯的各位老師! 李強(qiáng)二OO九年六月 于南京參 考 文 獻(xiàn)1.吳磊編著. 手把手教你學(xué)UG NX. 北京:電子工業(yè)出版社,2.袁鋒. UG機(jī)械設(shè)計(jì)工程范例教程. 北京:機(jī)械工業(yè)出版社,3.曹巖. UG NX工程應(yīng)用教程. 北京:機(jī)械工業(yè)出版社,4.王建華,王妮. UG在高速加工數(shù)控編程中的應(yīng)用. 航天制造技術(shù),第5期,20065.鄭貞平,喻德,張小紅. UG NX6中文版數(shù)控加工典型范例. 北京:電子工業(yè)出版社,6.衛(wèi)兵工作室編著. UG NX數(shù)控加工實(shí)例教程. 北京:清華大學(xué)出版社,7. 郝一舒,趙卿. 基于UG的5軸數(shù)控高速銑削中心在仿真加工中的應(yīng)用. 制造業(yè)自動(dòng)化,第9期,20078.席平,宋玉旺. 基于UG的制造輔助系統(tǒng). 航天制造技術(shù),第7期,20069.吳磊編著. UG NX中文版曲面設(shè)計(jì)典型范例教程. 北京:電子工業(yè)出版社,10.王志峰,高錦輝,第5期,200711. 陳曉英,徐誠(chéng). UG軟件在數(shù)控加工中的應(yīng)用. 機(jī)床與液壓,第1期,200612.呂文閣,陸藝華. ,第10期,2007附錄A:英文資料The puter in Die Design (CAD)The term CAD is alternately used to mean puter aided design and puter aided drafting. Actually it can mean either one or both of these concepts, and the tool designer will have occasion to use it in both forms.CAD puter aided design means using the puter and peripheral devices to simplify and enhance the design process. CAD puter aided drafting means using the puter and peripheral devices to produce the documentation and graphics for the design process. This documentation usually includes such things as preliminary drawings, working drawings, parts lists, and design calculations.A CAD system, whether taken to mean puter aided design system or puter aided drafting system, consists of three basic ponents。 hardware, software, users. The hardware ponents of a typical CAD system include a processor, a system display, a keyboard, a digitizer, and a plotter. The software ponent of a CAD system consists of the programs which allow it to perform design and drafting functions. The user is the tool designer who uses the hardware and software to simplify and enhance the design process.Graphics displays represented the first real step toward bringing the worlds of tool design and the puter together. The plotters depicted in Figure, represented the next step. With the advent of the digitizing tablet in the early 196039。s, CAD hardware as we know it today began to take shape. The development of puter graphics software followed soon after these hardware developments.Early CAD system were large, cumbersome, and expensive. So expensive, in fact that only the largest panies could afford them. During the late 1960’s CAD was looked on as an interesting, but impractical novelty that had only limited potential in tool design applications. However, with the introduction of the silicon chip during the 197039。s, puters began to take their place in the world of tool design.Integrated circuits on silicon chips allowed full scale puters to be packaged in small consoles no larger than television sets. These miniputers had all of the characteristics of full scale puters, but they were smaller and considerably less expensive. Even smaller puters called microputers followed soon after.The 197O39。s saw continued advances in CAD hardware and software technology. So much so that by the beginning of the 198039。s, making and marketing CAD system had bee a growth industry. Also, CAD has been transformed from its status of impractical novelty to its new status as one of the most important inventions to date. By 1980, numerous CAD systems were available ranging in sizes from microputer systems to large miniputer and mainframe system.Mold Making Using CIMComputerintegrated manufacturing (CIM) represents integration of electronic data processing (EDP) into all departments associated with planning and production of an objec