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本科生畢業(yè)設(shè)計(jì)(論文)開題報(bào)告
論文(設(shè)計(jì))題目
泵體零件數(shù)控加工工藝設(shè)計(jì)、
編程及夾具設(shè)計(jì)
作者所在系別
機(jī)電工程學(xué)院
作者所在專業(yè)
車輛工程
作者所在班級(jí)
B13142
作 者 姓 名
郝立新
作 者 學(xué) 號(hào)
201322375
指導(dǎo)教師姓名
趙秋芳
指導(dǎo)教師職稱
副教授
完 成 時(shí) 間
2017
年
3
月
北華航天工業(yè)學(xué)院教務(wù)處制
說(shuō) 明
1.根據(jù)學(xué)?!懂厴I(yè)設(shè)計(jì)(論文)工作暫行規(guī)定》,學(xué)生必須撰寫《畢業(yè)設(shè)計(jì)(論文)開題報(bào)告》。開題報(bào)告作為畢業(yè)設(shè)計(jì)(論文)答辯委員會(huì)對(duì)學(xué)生答辯資格審查的依據(jù)材料之一。
2.開題報(bào)告應(yīng)在指導(dǎo)教師指導(dǎo)下,由學(xué)生在畢業(yè)設(shè)計(jì)(論文)工作前期內(nèi)完成,經(jīng)指導(dǎo)教師簽署意見及所在專業(yè)教研室論證審查后生效。開題報(bào)告不合格者需重做。
3.畢業(yè)設(shè)計(jì)開題報(bào)告各項(xiàng)內(nèi)容要實(shí)事求是,逐條認(rèn)真填寫。其中的文字表達(dá)要明確、嚴(yán)謹(jǐn),語(yǔ)言通順,外來(lái)語(yǔ)要同時(shí)用原文和中文表達(dá)。第一次出現(xiàn)縮寫詞,須注出全稱。
4.開題報(bào)告中除最后一頁(yè)外均由學(xué)生填寫,填寫各欄目時(shí)可根據(jù)內(nèi)容另加附頁(yè)。
5.閱讀的主要參考文獻(xiàn)應(yīng)在10篇以上(土建類專業(yè)文獻(xiàn)篇數(shù)可酌減),其中外文資料應(yīng)占一定比例。本學(xué)科的基礎(chǔ)和專業(yè)課教材一般不應(yīng)列為參考資料。
6.參考文獻(xiàn)的書寫應(yīng)遵循畢業(yè)設(shè)計(jì)(論文)撰寫規(guī)范要求。
7.開題報(bào)告應(yīng)與文獻(xiàn)綜述、一篇外文譯文和外文原文復(fù)印件同時(shí)提交,文獻(xiàn)綜述的撰寫格式按畢業(yè)設(shè)計(jì)(論文)撰寫規(guī)范的要求,字?jǐn)?shù)在2000字左右。
畢業(yè)設(shè)計(jì)(論文)開題報(bào)告
學(xué)生姓名
郝立新
專 業(yè)
車輛工程
班 級(jí)
B13142
指導(dǎo)教師姓名
趙秋芳
職 稱
副教授
工作單位
北華航天工業(yè)學(xué)院
課題來(lái)源
校企合作
課題性質(zhì)
應(yīng)用研究
課題名稱
泵體數(shù)控加工工藝設(shè)計(jì)、編程及夾具設(shè)計(jì)
本設(shè)計(jì)的科學(xué)依據(jù)
(科學(xué)意義和應(yīng)用前景,國(guó)內(nèi)外研究概況,目前技術(shù)現(xiàn)狀、水平和發(fā)展趨勢(shì)等)
數(shù)控技術(shù)在機(jī)械加工生產(chǎn)中的運(yùn)用實(shí)現(xiàn)了機(jī)械加工制造的歷史性改革。應(yīng)用數(shù)字化信息技術(shù)對(duì)機(jī)床的運(yùn)動(dòng)以及加工過(guò)程完成各個(gè)方面的管理和控制,應(yīng)用數(shù)控設(shè)備和可編程設(shè)備等多個(gè)系統(tǒng)完成一系列系統(tǒng)化的操作,進(jìn)而在一定程度上提升機(jī)械加工生產(chǎn)精度,滿足技術(shù)有關(guān)需求。
目前企業(yè)主要采用單件生產(chǎn)、多品種/小批量和重復(fù)大批量生產(chǎn)等多種方式。多樣化經(jīng)營(yíng)模式、工藝復(fù)雜,所需設(shè)備和工裝繁多。多采用工序集中原則,隨著技術(shù)發(fā)展生活水品提高多品種高質(zhì)量的產(chǎn)品越來(lái)越多的為人們所需。所以采取了更多更為復(fù)雜的工藝作為支撐。目前采用CAPP編制工藝很普遍。成組工序在工藝中得到廣泛的運(yùn)用它允許采用同一設(shè)備和工藝裝置,以及相同或相近的機(jī)床調(diào)整方式來(lái)加工工全組零件。夾具也經(jīng)歷了一個(gè)大變革,從最初的基本加工輔助設(shè)備發(fā)展至今成為一種門類齊全的工藝裝備。
現(xiàn)如今出現(xiàn)了更多的柔性制造對(duì)夾具提出了更高的要求。未來(lái)夾具正向著標(biāo)準(zhǔn)化、精密化、高效化、柔性化發(fā)展。當(dāng)前國(guó)外先進(jìn)的制造工藝是將泵體和泵蓋分別加工,然后組合到一起進(jìn)行產(chǎn)品的總裝,在保證精度的前提下,大大提高了加工效率,降低了成本。落后就要挨打,在這需求多變精益求精的當(dāng)代采用多工藝生產(chǎn)出高質(zhì)量高品質(zhì)的泵體部件仍需要泵行業(yè)不懈努力。
設(shè)計(jì)內(nèi)容和預(yù)期成果
(具體設(shè)計(jì)內(nèi)容和重點(diǎn)解決的技術(shù)問(wèn)題、預(yù)期成果和提供的形式)
本設(shè)計(jì)是泵體零件工藝編程及夾具設(shè)計(jì)。首先分析零件結(jié)構(gòu)、作用、工藝性,然后進(jìn)行工藝規(guī)程設(shè)計(jì)、夾具設(shè)計(jì)、編制說(shuō)明書。主要內(nèi)容包括:生產(chǎn)類型、零件的作用、結(jié)構(gòu)特點(diǎn)、結(jié)構(gòu)工藝性、關(guān)鍵表面的技術(shù)要求分析等。然后進(jìn)行工藝設(shè)計(jì),主要內(nèi)容包括:確定毛坯類型;毛坯選擇與說(shuō)明;工藝路線的確定(粗、精基準(zhǔn)的選擇,各表面的加工方法的確定,工序集中與分散的考慮,工序順序的安排的原則,加工設(shè)備與工裝的選擇,不同方案的分析比較等);加工余量、切削用量及基本時(shí)間、工序尺寸與公差的確定。然后根據(jù)工藝進(jìn)行數(shù)控編程。最后進(jìn)行專用夾具設(shè)計(jì),主要內(nèi)容包括:夾具設(shè)計(jì)思想與不同。方案的對(duì)比;定位裝置和對(duì)刀及導(dǎo)引裝置的選擇;夾緊機(jī)構(gòu)設(shè)計(jì)與夾緊力的計(jì)算。
重點(diǎn)解決的技術(shù)問(wèn)題:粗、精基準(zhǔn)的選擇,工序順序的安排,機(jī)床與工裝的選擇,加工余量、切削用量的計(jì)算,編程定位裝置與對(duì)刀裝置的選擇,夾緊力的計(jì)算。
預(yù)期成果及提供形式:工序卡片一套,泵體二維零件圖及三維實(shí)物圖,一套夾具裝配圖一張,一套夾具零件圖一張,設(shè)計(jì)說(shuō)明書一份。
擬采取設(shè)計(jì)方法和技術(shù)支持
(設(shè)計(jì)方案、技術(shù)要求、實(shí)驗(yàn)方法和步驟、可能遇到的問(wèn)題和解決辦法等)
設(shè)計(jì)方案:首先對(duì)零件進(jìn)行分析,然后對(duì)給定零件進(jìn)行工藝過(guò)程設(shè)計(jì),編寫加工程序,制訂編制相應(yīng)的工序卡片,最后進(jìn)行專用夾具的設(shè)計(jì)。
技術(shù)要點(diǎn):分析零件、選擇定位基準(zhǔn)、制訂加工順序、計(jì)算工序尺寸、制訂切削參數(shù)、制訂工時(shí)定額等。根據(jù)現(xiàn)有機(jī)床刀具進(jìn)行編程。準(zhǔn)備所有設(shè)計(jì)資料;制訂合理的定位方案,并設(shè)計(jì)定位元件結(jié)構(gòu);制訂合理的夾緊方案,并設(shè)計(jì)夾緊結(jié)構(gòu)設(shè)計(jì)夾具體;標(biāo)注合理的技術(shù)要求,并分析精度是否滿足要求;對(duì)夾具進(jìn)行技術(shù)經(jīng)濟(jì)分析。
可能遇到的問(wèn)題及解決辦法:1、基準(zhǔn)如何選擇定位基準(zhǔn)的選擇。 2、工序順序如何安排。3、工序尺寸、切削參數(shù)、工時(shí)定額的有關(guān)計(jì)算。 4、如何完成整套編程。5、如何制訂夾具方案。
對(duì)以上可能遇到的問(wèn)題積極查詢公司資料和已有生產(chǎn)經(jīng)驗(yàn),并及時(shí)和老師以及公司溝通、交流、反饋。
實(shí)現(xiàn)本項(xiàng)目預(yù)期目標(biāo)和已具備的條件
(包括過(guò)去學(xué)習(xí)、研究工作基礎(chǔ),現(xiàn)有主要儀器設(shè)備、設(shè)計(jì)環(huán)境及協(xié)作條件等)
在機(jī)械制造技術(shù)基礎(chǔ)的學(xué)習(xí)期間對(duì)夾具的設(shè)計(jì)和零件的加工工藝設(shè)計(jì)有了一定的掌握。通過(guò)實(shí)習(xí)和自學(xué)掌握了編程知識(shí)。中國(guó)知網(wǎng)上浩瀚的論文期刊為我們更好的去了解提供了優(yōu)越的條件。在機(jī)床、夾具、刀具的選用上以數(shù)控機(jī)床為主。在公司可以實(shí)時(shí)向老師傅咨詢問(wèn)題,在公司室內(nèi)完成。
各環(huán)節(jié)擬定階段性工作進(jìn)度
(以周為單位)
1、查閱資料,撰寫文獻(xiàn)綜述; 1周
2、根據(jù)撰寫的文獻(xiàn)綜述填寫開題報(bào)告,并查找與之相關(guān)的外文資料并翻譯; 1周
3、準(zhǔn)備各種資料,熟悉零件圖,并繪制零件圖; 1周
4、完成機(jī)械加工過(guò)程的設(shè)計(jì); 1周
5、對(duì)所設(shè)計(jì)的加工工藝進(jìn)行技術(shù)經(jīng)濟(jì)分析; 1周
6、完成工藝技術(shù)經(jīng)濟(jì)分析報(bào)告; 1周
7、編寫工序卡片; 1周
8、根據(jù)工序內(nèi)容編寫數(shù)控程序; 1周
9、對(duì)程序進(jìn)行模擬; 1周
10、根據(jù)工序內(nèi)容編寫夾具設(shè)計(jì)任務(wù)書; 1周
11、設(shè)計(jì)專用夾具; 1周
12、拆一套零件圖; 1周
13、拆第二套零件圖; 1周
14、完成設(shè)計(jì)說(shuō)明書一份; 1周
15、對(duì)所設(shè)計(jì)的專用夾具進(jìn)行技術(shù)經(jīng)濟(jì)分析,并完成分析報(bào)告; 1周
16、其它時(shí)間:機(jī)動(dòng)處理,比如整理打印圖紙、打印裝訂分析報(bào)告,答準(zhǔn)備等。 1周
開 題 報(bào) 告 審 定 紀(jì) 要
時(shí) 間
地點(diǎn)
主持人
參
會(huì)
教
師
姓 名
職 務(wù)(職 稱)
姓 名
職 務(wù)(職 稱)
論
證
情
況
摘
要
記錄人:
指
導(dǎo)
教
師
意
見
指導(dǎo)教師簽名: 年 月 日
教
研
室
意
見
教研室主任簽名: 年 月 日
5
本科生畢業(yè)設(shè)計(jì)(論文)文獻(xiàn)綜述
設(shè)計(jì) (論文)題目
泵體零件數(shù)控加工工藝設(shè)計(jì)、
編程及夾具設(shè)計(jì)
作者所在系別
機(jī)電工程學(xué)院
作者所在專業(yè)
車輛工程
作者所在班級(jí)
B13142
作 者 姓 名
郝立新
作 者 學(xué) 號(hào)
201322375
指導(dǎo)教師姓名
趙秋芳
指導(dǎo)教師職稱
副教授
完 成 時(shí) 間
2017
年
3
月
北華航天工業(yè)學(xué)院教務(wù)處制
說(shuō) 明
1.根據(jù)學(xué)?!懂厴I(yè)設(shè)計(jì)(論文)工作暫行規(guī)定》,學(xué)生必須撰寫畢業(yè)設(shè)計(jì)(論文)文獻(xiàn)綜述。文獻(xiàn)綜述作為畢業(yè)設(shè)計(jì)(論文)答辯委員會(huì)對(duì)學(xué)生答辯資格審查的依據(jù)材料之一。
2.文獻(xiàn)綜述應(yīng)在指導(dǎo)教師指導(dǎo)下,由學(xué)生在畢業(yè)設(shè)計(jì)(論文)工作前期內(nèi)完成,由指導(dǎo)教師簽署意見并經(jīng)所在專業(yè)教研室審查。
3.文獻(xiàn)綜述各項(xiàng)內(nèi)容要實(shí)事求是,文字表達(dá)要明確、嚴(yán)謹(jǐn),語(yǔ)言通順,外來(lái)語(yǔ)要同時(shí)用原文和中文表達(dá)。第一次出現(xiàn)縮寫詞,須注出全稱。
4.學(xué)生撰寫文獻(xiàn)綜述,閱讀的主要參考文獻(xiàn)應(yīng)在10篇以上(土建類專業(yè)文獻(xiàn)篇數(shù)可酌減),其中外文資料應(yīng)占一定比例。本學(xué)科的基礎(chǔ)和專業(yè)課教材一般不應(yīng)列為參考資料。
5.文獻(xiàn)綜述的撰寫格式按畢業(yè)設(shè)計(jì)(論文)撰寫規(guī)范的要求,字?jǐn)?shù)在2000字左右。文獻(xiàn)綜述應(yīng)與開題報(bào)告同時(shí)提交。
畢 業(yè) 設(shè) 計(jì)(論 文)文 獻(xiàn) 綜 述
文獻(xiàn)綜述題目
摘要:
隨著機(jī)械制造業(yè)的發(fā)展,傳統(tǒng)的加工技術(shù)已經(jīng)不能滿足現(xiàn)代制造業(yè)發(fā)展的需要。數(shù)控技術(shù)在機(jī)械加工中的合理應(yīng)用將對(duì)現(xiàn)代工業(yè)的發(fā)展起到至關(guān)重要的作用。本文介紹了泵體在實(shí)際加工過(guò)程中的數(shù)控編程、工藝及夾具的具體內(nèi)容,通過(guò)查閱資料分析了數(shù)控技術(shù)加工的國(guó)內(nèi)外發(fā)展現(xiàn)狀,還分析了機(jī)械數(shù)控加工工藝的發(fā)展趨勢(shì)與發(fā)展方向。
關(guān)鍵詞:數(shù)控技術(shù);泵體工藝;夾具設(shè)計(jì)
Abstract:
With the development of machinery manufacturing, the traditional processing technology has been unable to meet the needs of modern manufacturing development. The rational application of CNC technology in machining will play a vital role in the development of modern industry. This paper introduces the specific contents of NC programming, process and fixture in the actual processing of the pump body. The status quo of the development of CNC machining at home and abroad is analyzed by referring to the data. The development trend and development direction of the CNC machining process are also analyzed.
Keyword: numerical technology,Pump body process,F(xiàn)ixture design
1 前言
數(shù)控技術(shù)在機(jī)械加工生產(chǎn)中的運(yùn)用實(shí)現(xiàn)了機(jī)械加工制造的歷史性改革。應(yīng)用數(shù)字化信息技術(shù)對(duì)機(jī)床的運(yùn)動(dòng)以及加工過(guò)程完成各個(gè)方面的管理和控制,應(yīng)用數(shù)控設(shè)備和可編程設(shè)備等多個(gè)系統(tǒng)完成一系列系統(tǒng)化的操作,進(jìn)而在一定程度上提升機(jī)械加工生產(chǎn)精度,滿足技術(shù)有關(guān)需求[6]。
機(jī)械加工工藝規(guī)程是規(guī)定產(chǎn)品或零件機(jī)械加工工藝過(guò)程和操作方法等最為合理的工藝文件,根據(jù)文件的工藝生產(chǎn)可使資源合理利用產(chǎn)能最大化。機(jī)床夾具是機(jī)床上裝夾工件的一種裝置,它保證了工件在機(jī)床和刀具的相對(duì)位置。在過(guò)去它僅僅是一種加工輔助裝置而現(xiàn)在已經(jīng)發(fā)展為一種重要的工藝裝備。使用夾具可以有效的保證加工質(zhì)量,提高生產(chǎn)效率,降低生產(chǎn)成本,減輕工人勞動(dòng)強(qiáng)度,保證安全生產(chǎn)等,因此,夾具在機(jī)械制造中占有重要的地位[7]。本課題主要問(wèn)題是實(shí)際生產(chǎn)中,用數(shù)控機(jī)床完成加工過(guò)程并完成編程。并處理好生產(chǎn)中工件的加工質(zhì)量、生產(chǎn)效率和經(jīng)濟(jì)性三者之間的關(guān)系。在實(shí)際加工中,要想完成整個(gè)零件的加工,工藝編程夾具都是必不可少的。
2 數(shù)控加工工藝及夾具的國(guó)內(nèi)外發(fā)展現(xiàn)狀
我國(guó)數(shù)控機(jī)床制造業(yè)在上世紀(jì)80年代曾有過(guò)高速發(fā)展的階段,許多機(jī)床廠從傳統(tǒng)產(chǎn)品實(shí)現(xiàn)向數(shù)控化產(chǎn)的轉(zhuǎn)型。但總的來(lái)說(shuō),技術(shù)水平不高,質(zhì)量不佳,所以在上世紀(jì)90年代初期面臨國(guó)家經(jīng)濟(jì)由計(jì)劃性經(jīng)濟(jì)市場(chǎng)經(jīng)濟(jì)轉(zhuǎn)移調(diào)整,國(guó)家從擴(kuò)大內(nèi)需啟動(dòng)機(jī)床市場(chǎng),加強(qiáng)限制進(jìn)口數(shù)控設(shè)備的審批,投資重點(diǎn)支持關(guān)鍵數(shù)控系統(tǒng)、設(shè)備、技術(shù)攻關(guān),對(duì)數(shù)控設(shè)備生產(chǎn)起到了很大的促進(jìn)作用。
目前,絕大多數(shù)國(guó)外生產(chǎn)的數(shù)控機(jī)床,已廣泛采用了32的系統(tǒng),而國(guó)內(nèi)生產(chǎn)的數(shù)控機(jī)床由于受到進(jìn)口技術(shù)的限制,大多采用的是16的系統(tǒng)。這就使得國(guó)產(chǎn)數(shù)控機(jī)床在功能上就先天不足,與國(guó)外數(shù)控機(jī)床相比,有明顯的差距。不論是加工中心或是數(shù)控車削中心,這類新型的數(shù)控設(shè)備均顯示出能滿足許多復(fù)雜零件在批量生產(chǎn)中的強(qiáng)大的生產(chǎn)力,一般均具有4一5軸連動(dòng),一次裝夾可進(jìn)行多面加工的功能Csl在程序控制下,可行主軸立、臥式自動(dòng)轉(zhuǎn)換,轉(zhuǎn)換前后均可自動(dòng)換刀,五座標(biāo)控制,五座標(biāo)連動(dòng),可以加工出六面體中的五面份次裝夾定位)及復(fù)雜的曲線型面和空間曲面體。計(jì)算機(jī)在機(jī)器制造的各個(gè)領(lǐng)域,已越來(lái)越被廣泛應(yīng)用,設(shè)備越來(lái)越趨向柔性化、智能化、多功能化[9]。
成組技術(shù)在制造工藝方面廣泛應(yīng)用。利用成組技術(shù)形成成組工序減少由于零件品種更換所需要的機(jī)床調(diào)整時(shí)間,于是便可大大提高生產(chǎn)的效率,降低生產(chǎn)成本。有了成組工序就可設(shè)計(jì)出與之相配的成組夾具。只要進(jìn)行少量的調(diào)整或更換某些零件,成組夾具就可適用于全組零件的工序安裝[8]。
國(guó)內(nèi)泵體類零件加工線的一個(gè)新突破是以三臺(tái)德國(guó)Ch iron高速加工中心為主體的VE分配泵泵體新的生產(chǎn)線,實(shí)踐證明,它工序高度集中,生產(chǎn)率高,加工精度高,輔助工序減少,并使生產(chǎn)計(jì)劃組織工作得以簡(jiǎn)化[1]。當(dāng)然由于工序高度集中,如果設(shè)備可靠性、使用維修、刀具管理跟不上,有可能產(chǎn)生單機(jī)瓶頸。這就要求加工設(shè)備具有良好的穩(wěn)定性和可靠性。因此對(duì)機(jī)床的主軸、傳動(dòng)部件、導(dǎo)軌、液壓系統(tǒng)、潤(rùn)滑系統(tǒng)、控制系統(tǒng)等提出了很高的要求[2]。在生產(chǎn)中采用先進(jìn)的機(jī)床和刀具,采用氣動(dòng)、液動(dòng)、多件裝夾等高效夾具,采用可換工作臺(tái)、可換夾具、多位夾具等可以使加工高效、簡(jiǎn)潔、可靠[3]。
3 數(shù)控加工工藝及夾具的發(fā)展趨勢(shì)與發(fā)展方向
現(xiàn)代機(jī)床數(shù)控系統(tǒng)發(fā)展總的來(lái)說(shuō)就是更加通用、開放、智能、人性化和柔性化。系統(tǒng)結(jié)構(gòu)除原有的并行總線系統(tǒng)以外,近幾年國(guó)際上又推出了串行總線數(shù)控系統(tǒng)。而且有關(guān)專家預(yù)測(cè),在新的世紀(jì)里,串行總線數(shù)控系統(tǒng)將逐漸取代并行總線數(shù)控系統(tǒng)。目前基于個(gè)人計(jì)算機(jī)(PC)的CNC數(shù)控系統(tǒng)(業(yè)界稱之為第六數(shù)控系統(tǒng)),是數(shù)控系統(tǒng)的又一種新的發(fā)展方向[10]。
現(xiàn)在主要是設(shè)備技術(shù)的集成。即機(jī)電一體化未來(lái)的集成化是讓整個(gè)產(chǎn)品從其設(shè)計(jì)、生產(chǎn)、裝配、檢驗(yàn)、出廠的全過(guò)程在一個(gè)自動(dòng)化系統(tǒng)內(nèi)完成[11]。
國(guó)外先進(jìn)的制造工藝是將泵體和泵蓋分別加工,然后組合到一起進(jìn)行產(chǎn)品的總裝,在保證精度的前提下,大大提高了加工效率,降低了成本。在大型泵體部件的加工工藝中,采用先進(jìn)的設(shè)備、工裝和檢測(cè)手段確保產(chǎn)品質(zhì)量,是泵行業(yè)不斷追求工藝技術(shù)創(chuàng)新和突破的努力方向[4]。
4 總結(jié)
綜上所述,在泵體零件數(shù)控加工工藝和專用夾具設(shè)計(jì)方面的研究,主要是從采用先進(jìn)的設(shè)備、工裝和檢測(cè)手段以及對(duì)機(jī)床夾具的要求等方面入手,盡量使工序集中,提高生產(chǎn)率,提高加工精度,減少輔助工序,降低成本,使生產(chǎn)計(jì)劃組織工作得以簡(jiǎn)化。但是由于工序高度集中容易造成單機(jī)瓶頸,這是一個(gè)需要解決的問(wèn)題,這些問(wèn)題出現(xiàn)在機(jī)床的穩(wěn)定性、可靠性,對(duì)設(shè)備的使用維護(hù)以及刀具的制造管理上。所以,對(duì)泵體零件機(jī)械加工工藝和專用夾具設(shè)計(jì)的研究仍要不斷進(jìn)行。
參考文獻(xiàn)
[1] 劉新亞. BQ型噴油泵泵體加工工藝的研究.航空制造技術(shù), 1996,2:17-18.
[2] 何世斌, 沈惠山, 朱心伍. VE泵泵體加工新工藝. 現(xiàn)代車用動(dòng)力, 2002, 3:32-35.
[3] 梅軍. 泵體的工藝改進(jìn). 機(jī)械工程師, 2009, 3:44.
[4] 夏國(guó)鋒.泵體的先進(jìn)加工方法.現(xiàn)代制造工程,2002,1:31-32.
[5] 張永泉,彭學(xué)斌. 大型雙吸泵泵體的加工藝及誤差分析. 通用機(jī)械, 2009,8:82-84.
[6] 梁春鴻.數(shù)控技術(shù)在機(jī)械加工中的應(yīng)用及其發(fā)展前景.中國(guó)高新技術(shù)企業(yè),2015,5:63
[7] 徐發(fā)仁.機(jī)床夾具設(shè)計(jì).重慶大學(xué)出版社, 1993:32-41.
[8] 張勝文,趙良才.計(jì)算機(jī)輔助工藝——CAPP系統(tǒng)設(shè)計(jì)(第二版).北京:機(jī)械工業(yè)出版社, 2010:18-21.
[9] 宋春華.?dāng)?shù)控技術(shù)的現(xiàn)狀及發(fā)展趨勢(shì).Equipment Manufactring, Technology2011.1:114
[10] 朱同興.國(guó)內(nèi)外數(shù)控技術(shù)發(fā)展動(dòng)向.兵工自動(dòng)化.2001 :10
[11] S.M.Hsiung.thermal–mechanical processes observed at the Drift-Scale Heater Test at Yucca Mountain, Nevada, USA, Elsevier Journal, 2005:23-25.
畢 業(yè) 設(shè) 計(jì)(論 文)文 獻(xiàn) 綜 述
指導(dǎo)教師意見
指導(dǎo)教師:
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本科生畢業(yè)設(shè)計(jì) (論文)
外 文 翻 譯
原 文 標(biāo) 題
The Effective Use in the Process of Numerical
Technology in Mechanical Manufacturing
譯 文 標(biāo) 題
數(shù)控技術(shù)在機(jī)械制造中的有效應(yīng)用
作者所在系別
機(jī)電工程學(xué)院
作者所在專業(yè)
車輛工程
作者所在班級(jí)
B13142
作 者 姓 名
郝立新
作 者 學(xué) 號(hào)
201322375
指導(dǎo)教師姓名
趙秋芳
指導(dǎo)教師職稱
副教授
完 成 時(shí) 間
2017
年
2
月
北華航天工業(yè)學(xué)院教務(wù)處制
譯文標(biāo)題
數(shù)控技術(shù)在機(jī)械制造中的有效應(yīng)用
原文標(biāo)題
The Effective Use in the Process of Numerical Control Technology in Mechanical Manufacturing
作 者
Lian Fu Yang; Hong Sun;
譯 名
無(wú)
國(guó) 籍
中國(guó)
原文出處
Trans Tech Publications
摘要:隨著機(jī)械制造業(yè)的發(fā)展,傳統(tǒng)的加工技術(shù)已經(jīng)不能滿足現(xiàn)代制造業(yè)發(fā)展的需要。數(shù)控技術(shù)改變了形勢(shì)。數(shù)控技術(shù)在機(jī)械加工中的合理應(yīng)用將對(duì)現(xiàn)代工業(yè)的發(fā)展起到至關(guān)重要的作用。本文分析了數(shù)控技術(shù)在機(jī)械制造中的應(yīng)用,通過(guò)對(duì)數(shù)控技術(shù)應(yīng)用現(xiàn)狀的研究,指出數(shù)控技術(shù)的發(fā)展趨勢(shì),指明了未來(lái)的發(fā)展方向。
關(guān)鍵詞:數(shù)控技術(shù);機(jī)械制造;有效應(yīng)用。
數(shù)控(N / C)是一種可編程的自動(dòng)化系統(tǒng),通過(guò)數(shù)字、字母和其他符號(hào)來(lái)控制加工設(shè)備。數(shù)字,字母和符號(hào)用適當(dāng)?shù)母袷骄幋a成一個(gè)特定工件的指令程序。更改作業(yè)時(shí),必須更改指令程序。改變程序可以使N / C適合于中小批次的生產(chǎn)。改寫程序要比改裝設(shè)備容易得多。
數(shù)控機(jī)床有兩種基本類型:點(diǎn)對(duì)點(diǎn)型和連續(xù)路徑型(又稱輪廓型)。點(diǎn)對(duì)點(diǎn)機(jī)采用異步電動(dòng)機(jī),其結(jié)果是加工頭位置只有一個(gè)運(yùn)動(dòng)或只由一個(gè)電動(dòng)機(jī)帶動(dòng)運(yùn)行。這種機(jī)器主要用于直線切割、鉆孔或鏜孔。
N / C系統(tǒng)由以下部分組成:數(shù)據(jù)輸入部分,帶控制單元的讀卡器,反饋裝置,和金屬切削機(jī)床或其他類型的N / C設(shè)備。
數(shù)據(jù)輸人裝置,也稱“人機(jī)聯(lián)系裝置”,可用人工或全自動(dòng)方法向機(jī)床提供數(shù)據(jù)。人工方法作為輸人數(shù)據(jù)唯一方法時(shí),只限于少量輸入。人工輸入裝置有鍵盤,撥號(hào)盤,按鈕,開關(guān)或撥輪選擇開關(guān),這些都位于機(jī)床附近的一個(gè)控制臺(tái)上。撥號(hào)盤通常連到一個(gè)同步解析器或電位計(jì)的模擬裝置上。在大多數(shù)情況下,按鈕、開關(guān)和其他類似的旋鈕是數(shù)據(jù)輸入元件。人工輸入需要操作者控制每個(gè)操作,這是一個(gè)既慢又單調(diào)的過(guò)程,除了簡(jiǎn)單加工場(chǎng)合或特殊情況,已很少使用。
幾乎所有情況下,信息都是通過(guò)卡片、穿孔紙帶或磁帶自動(dòng)提供給控制單元。在傳統(tǒng)的數(shù)控系統(tǒng)中,八信道穿孔紙帶是最常用的數(shù)據(jù)輸入形式,紙帶上的編碼指令由一系列稱為程序塊的穿孔組成。每一個(gè)程序塊代表一種加工功能、一種操作或兩者的組合。紙帶上的整個(gè)數(shù)控程序由這些連續(xù)數(shù)據(jù)單元連接而成。帶有程序的長(zhǎng)帶子像電影膠片一樣繞在盤子上,相對(duì)較短的帶子上的程序可通過(guò)將紙帶兩端連接形成一個(gè)循環(huán)而連續(xù)不斷地重復(fù)使用。帶子一旦安裝好,就可反復(fù)使用而無(wú)需進(jìn)一步處理。此時(shí),操作者只是簡(jiǎn)單地上、下工件。穿孔紙帶是在帶有特制穿孔附件的打字機(jī)或直接連到計(jì)算機(jī)上的紙帶穿孔裝置上做成的。紙帶制造很少不出錯(cuò),錯(cuò)誤可能由編程、卡片穿孔或編碼、紙帶穿孔時(shí)的物理?yè)p害等形成。通常,必須要試走幾次來(lái)排除錯(cuò)誤,才能得到一個(gè)可用的工作紙帶。
雖然紙帶上的數(shù)據(jù)是自動(dòng)進(jìn)給的,但實(shí)際編程卻是手工完成的,在編碼紙帶做好前,編程者經(jīng)常要和一個(gè)計(jì)劃人員或工藝工程師一起工作,選擇合適的數(shù)控機(jī)床,決定加工材料,計(jì)算切削速度和進(jìn)給速度,決定所需刀具類型,仔細(xì)閱讀零件圖上尺寸,定下合適的程序開始的零參考點(diǎn),然后寫出程序清單,其上記載有描述加工順序的編碼數(shù)控指令,機(jī)床按順序加工工件到圖樣要求。
控制單元接受和儲(chǔ)存編碼數(shù)據(jù),直至形成一個(gè)完整的信息程序塊,然后解釋數(shù)控指令,并引導(dǎo)機(jī)床得到所需運(yùn)動(dòng)。
為更好理解控制單元的作用,可將它與撥號(hào)電話進(jìn)行比較,即每撥一個(gè)數(shù)字,就儲(chǔ)存一個(gè),當(dāng)整個(gè)數(shù)字撥好后,電話就被激活,也就完成了呼叫。
裝在控制單元里的紙帶閱讀機(jī),通過(guò)其內(nèi)的硅光二極管,檢測(cè)到穿過(guò)移動(dòng)紙帶上的孔漏過(guò)的光線,將光束轉(zhuǎn)變成電能,并通過(guò)放大來(lái)進(jìn)一步加強(qiáng)信號(hào),然后將信號(hào)送到控制單元里的寄存器,由它將動(dòng)作信號(hào)傳到機(jī)床驅(qū)動(dòng)裝置。
有些光電裝置能以高達(dá)每秒1000個(gè)字節(jié)的速度閱讀,這對(duì)保持機(jī)床連續(xù)動(dòng)作是必須的,否則,在輪廓加工時(shí),刀具可能在工件上產(chǎn)生劃痕。閱讀裝置必須要能以比控制系統(tǒng)處理數(shù)據(jù)更快的速度來(lái)閱讀數(shù)據(jù)程序塊。
反饋裝置是用在一些數(shù)控設(shè)備上的安全裝置,它可連續(xù)補(bǔ)償控制位置與機(jī)床運(yùn)動(dòng)滑臺(tái)的實(shí)際位置之間的誤差。裝有這種直接反饋檢查裝置的數(shù)控機(jī)床有一個(gè)閉環(huán)系統(tǒng)裝置。位置控制通過(guò)傳感器實(shí)現(xiàn),在實(shí)際工作時(shí),記錄下滑臺(tái)的位置,并將這些信息送回控制單元。接受到的信號(hào)與紙帶輸入的信號(hào)相比較,它們之間的任何偏差都可得到糾正。
在另一個(gè)稱為開環(huán)的系統(tǒng)中,機(jī)床僅由響應(yīng)控制器命令的步進(jìn)電動(dòng)機(jī)驅(qū)動(dòng)定位,工件的精度幾乎完全取決于絲杠的精度和機(jī)床結(jié)構(gòu)的剛度。有幾個(gè)理由可以說(shuō)明步進(jìn)電機(jī)是一個(gè)自動(dòng)化申請(qǐng)的非常有用的驅(qū)動(dòng)裝置。對(duì)于一件事物,它被不連續(xù)直流電壓脈沖驅(qū)使,是來(lái)自數(shù)傳計(jì)算機(jī)和其他的自動(dòng)化的非常方便的輸出控制系統(tǒng)。當(dāng)多數(shù)是索引或其他的自動(dòng)化申請(qǐng)所必備者的時(shí)候,步進(jìn)電機(jī)對(duì)運(yùn)行一個(gè)精確的有角進(jìn)步也是理想的。因?yàn)榭刂葡到y(tǒng)不需要監(jiān)聽就提供特定的輸出指令而且期待系統(tǒng)適當(dāng)?shù)胤磻?yīng)的公開- 環(huán)操作造成一個(gè)回應(yīng)環(huán),步進(jìn)電機(jī)是理想的。 一些工業(yè)的機(jī)械手使用高抬腿運(yùn)步的馬乘汽車駕駛員,而且步進(jìn)電機(jī)是有用的在數(shù)字受約束的工作母機(jī)中。 這些申請(qǐng)的大部分是公開- 環(huán) ,但是雇用回應(yīng)環(huán)檢測(cè)受到驅(qū)策的成份位置是可能的。 環(huán)的一個(gè)分析者把真實(shí)的位置與需要的位置作比較,而且不同是考慮過(guò)的錯(cuò)誤。 那然后駕駛員能發(fā)行對(duì)步進(jìn)電機(jī)的電脈沖,直到錯(cuò)誤被減少對(duì)準(zhǔn)零位。在這個(gè)系統(tǒng)中,沒有信息反饋到控制單元的自矯正過(guò)程。出現(xiàn)誤動(dòng)作時(shí),控制單元繼續(xù)發(fā)出電脈沖。比如,一臺(tái)數(shù)控銑床的工作臺(tái)突然過(guò)載,阻力矩超過(guò)電機(jī)轉(zhuǎn)矩時(shí),將沒有響應(yīng)信號(hào)送回到控制器。因?yàn)?,步進(jìn)電機(jī)對(duì)載荷變化不敏感,所以許多數(shù)控系統(tǒng)設(shè)計(jì)允許電機(jī)停轉(zhuǎn)。然而,盡管有可能損壞機(jī)床結(jié)構(gòu)或機(jī)械傳動(dòng)系統(tǒng),也有使用帶有特高轉(zhuǎn)矩步進(jìn)電機(jī)的其他系統(tǒng),此時(shí),電動(dòng)機(jī)有足夠能力來(lái)應(yīng)付系統(tǒng)中任何偶然事故。
最初的數(shù)控系統(tǒng)采用開環(huán)系統(tǒng)。在開、閉環(huán)兩種系統(tǒng)中,閉環(huán)更精確,一般說(shuō)來(lái)更昂貴。起初,因?yàn)樵葌鹘y(tǒng)的步進(jìn)電動(dòng)機(jī)的功率限制,開環(huán)系統(tǒng)幾乎全部用于輕加工場(chǎng)合,最近出現(xiàn)的電液步進(jìn)電動(dòng)機(jī)已越來(lái)越多地用于較重的加工領(lǐng)域。
附錄:
The Effective Use in the Process of Numerical Control Technology in Mechanical Manufacturing
Numerical control (N/C) is a form of programmable automation in which the processing equipment is controlled by means of numbers, letters and other symbols. The numbers, letters, and symbols are coded in an appropriate format to define a program of instructions for a particular workpart or job. When the job is changed, the program of instructions must be changed. The capability to change the program is what makes N/C suitable for low-volume and medium-volume production. It is much easier to write programs than to make major alterations of the processing equipment.
There are two basic types of numerically controlled machine tools: point—to—point and continuous—path (also called contouring). Point—to—point machines use unsynchronized motors, with the result that the position of the machining head Can be assured only upon completion of a movement, or while only one motor is running. Machines of this type are principally used for straight—line cuts or for drilling or boring.
The N/C system consists of the following components: data input, the tape reader with the control unit, feedback devices, and the metal—cutting machine tool or other type of N/C equipment.
Data input, also called “man—to—control link”, may be provided to the machine tool manually, or entirely by automatic means. Manual methods when used as the sole source of input data are restricted to a relatively small number of inputs. Examples of manually operated devices are keyboard dials, pushbuttons, switches, or thumbwheel selectors. These are located on a console near the machine. Dials ale analog devices usually connected to a synchronization-type resolver or potentiometer. In most cases, pushbuttons, switches and other similar types of selectors are digital input devices. Manual input requires that the operator set the controls for each operation. It is a slow and tedious process and is seldom justified except in elementary machining applications or in special cases.
In practically all cases, information is automatically supplied to the control unit and the machine tool by cards, punched tapes, or by magnetic tape. Eight—channel punched paper tape is the most commonly used form of data input for conventional N/C systems. The coded instructions on the tape consist of sections of punched holes called blocks. Each block represents a machine function, a machining operation, or a combination of the two. The entire N/C program on a tape is made up of an accumulation of these successive data blocks, Programs resulting in long tapes all wound on reels like motion-picture film. Programs on relatively short tapes may be continuously repeated by joining the two ends of the tape to form a loop. Once installed, the tape is used again and again without further handling. In this case, the operator simply loads and unloads the parts. Punched tapes ale prepared on type writers with special tape—punching attachments or in tape punching units connected directly to a computer system. Tape production is rarely error-free. Errors may be initially caused by the part programmer, in card punching or compilation, or as a result of physical damage to the tape during handling, etc. Several trial runs are often necessary to remove all errors and produce an acceptable working tape.
While the data on the tape is fed automatically, the actual programming steps ale done manually, Before the coded tape may be prepared, the programmer, often working with a planner or a process engineer, must select the appropriate N/C machine tool, determine the kind of material to be machined, calculate the speeds and feeds, and decide upon the type of tooling needed. The dimensions on the part print are closely examined to determine a suitable zero reference point from which to start the program. A program manuscript is then written which gives coded numerical instructions describing the sequence of operations that the machine tool is required to follow to cut the part to the drawing specifications.
The control unit receives and stores all coded data until a complete block of information has been accumulated. It then interprets the coded instruction and directs the machine tool through the required motions.
The function of the control unit may be better understood by comparing it to the action of a dial telephone, where, as each digit is dialed, it is stored. When the entire number has been dialed, the equipment becomes activated and the call is completed.
Silicon photo diodes, located in the tape reader head on the control unit, detect light as it passes through the holes in the moving tape. The light beams are converted to electrical energy, which is amplified to further strengthen the signal. The signals are then sent to registers in the control unit, where actuation signals are relayed to the machine tool drives.
Some photoelectric devices are capable of reading at rates up to 1000 characters per second. High reading rates are necessary to maintain continuous machine—tool motion; otherwise dwell marks may be generated by the cutter on the part during contouring operations. The reading device must be capable of reading data blocks at a rate faster than the control system can process the data.
A feedback device is a safeguard used on some N/C installations to constantly compensate for errors between the commanded position and the actual location of the moving slides of the machine tool. An N/C machine equipped with this kind of a direct feedback checking device has what is known as a closed-loop system. Positioning control is accomplished by a sensor which, during the actual operation, records the position of the slides and relays this information back to the control unit. Signals thus received ale compared to input signals on the tape, and any discrepancy between them is automatically rectified.
In an alternative system, called an open—loop system, the machine is positioned solely by stepping motor drives in response to commands by a controllers. There are three basic types of NC motions, as follows:
Point-to-point or Positional Control In point-to-point control the machine tool elements (tools, table, etc.) are moved to programmed locations and the machining operations performed after the motions are completed. The path or speed of movement between locations is unimportant; only the coordinates of the end points of the motions are accurately controlled. This type of control is suitable for drill presses and some boring machines, where drilling, tapping, or boring operations must be performed at various locations on the work piece. Straight-Line or Linear Control Straight-Line control systems are able to move the cutting tool parallel to one of the major axes of the machine tool at a controlled rate suitable for machining. It is normally only possible to move in one direction at a time, so angular cuts on the work piece are not possible, consequently, for milling machines, only rectangular configurations can be machined or for lathes only surfaces parallel or perpendicular to the spindle axis can be machined. This type of controlled motion is often referred to as linear control or a half-axis of control. Machines with this form of control are also capable of point-to-point control.
Continuous Path or Contouring Control In continuous path control the motions of two or more of the machine axes are controlled simultaneously, so that the position and velocity of the can be tool are changed continuously. In this way curves and surfaces can be machined at a controlled feed rate. It is the function of the interpolator in the controller to determine the increments of the individual controlled axes of the machines necessary to produce the desired motion. This type of control is referred to as continuous control or a full axis of control.
Some terminology concerning controlled motions for NC machines has been introduced. For example, some machines are referred to as four-or five-or even six-axis machines. For a vertical milling machine three axes of control are fairly obvious, these being the usual X, Y, Z coordinate directions. A fourth or fifth axis of control would imply some form of rotary table to index the work piece or possibly to provide angular motion of the work head. Thus, in NC terminology an axis of control is any controlled motion of the machine elements (spindles, tables, etc). A further complication is use of the term half-axis of control; for example, many milling machines are referred to as 2.5-axis machine. This means that continuous control is possible for two motions (axes) and only linear control is possible for the third axis. Applied to vertical milling machines, 2.5axis control means contouring in the X, Y plane and linear motion only in the Z direction. With these machines three-dimensional objects have to be machined with water lines around the surface at different heights. With an alternative terminology the same machine could be called a 2CL machine (C for continuous, L for linear control). Thus, a milling machine with continuous control in the X, Y, Z directions could be termed be a three-axis machine or a 3c machine. Similarly, lathes are usually two axis or 2C machines. The degree of work precision depends almost entirely upon the accuracy of the lead screw and the rigidity of the machine structure. With this system, there is no self-correcting action or feedback of information to the control unit. In the event of an unexpected malfunction, the control unit continues to put out pulses of electrical current. If, for example, the table on an N/C milling machine were suddenly to become overloaded, no response would be sent back to the controller. Because stepping motors are not sensitive to load variations, many N/C systems are designed to permit the motors to stall when the resisting torque exceeds the motor torque. Other systems are in use, however, which in spite of the possibility of damage to the machine structure or to the mechanical system, ale designed with special high—torque stepping motors. In this case, the motors have sufficient capacity to “overpower” the system in the event of almost any contingency.
The original N/C used the closed—loop system. Of the two systems, closed and open loop, closed loop is more accurate and, as a consequence, is generally more expensive. Initially, open—loop systems were used almost entirely for light-duty applications because of inherent power limitations previously associated with conventional electric stepping motors. Recent advances in the development of electro hydraulic stepping motors have led to increasingly heavier machine load applications.
參考文獻(xiàn)
[1]LianFuYang,HongSun.TheEffectiveUseintheProcessofNumericalControlTechnologyinMechanicalManufacturing[J].AppliedMechanicsandMaterials,2014,2948(496).
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