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山東輕工業(yè)學(xué)院
畢業(yè)設(shè)計(jì)(論文)中期進(jìn)展報(bào)告表
學(xué)院
機(jī)械與汽車工程學(xué)院
專業(yè)班級(jí)
機(jī)械08-2班
學(xué)生姓名
張淇翔
學(xué)號(hào)
200801011074
導(dǎo)師姓名
范維華
設(shè)計(jì)(論文)題 目
重力滾道輸送機(jī)阻尼裝置設(shè)計(jì)
根據(jù)設(shè)計(jì)要求和重力滾道輸送機(jī)阻尼裝置的性能參數(shù),在老師的指導(dǎo)下,前段時(shí)間主要完成了開題報(bào)告、英文翻譯、實(shí)習(xí)報(bào)告的工作,并查閱相關(guān)的資料,擬定了設(shè)計(jì)方案。初步完成了阻尼裝置基本機(jī)構(gòu)的設(shè)計(jì),傳動(dòng)機(jī)構(gòu)的設(shè)計(jì),重力滾道輸送機(jī)的整體結(jié)構(gòu)圖。
為了防止輸送物下滑過快而造成的不必要的損失,應(yīng)正確選擇輥道傾角。摩擦系數(shù)的選擇查閱了機(jī)械設(shè)計(jì)。
阻尼裝置,采用一套齒輪行星輪系傳動(dòng)機(jī)構(gòu),確定了阻尼型式。傳動(dòng)設(shè)計(jì)參考了機(jī)械設(shè)計(jì)與機(jī)械原理。
完成了重力滾道輸送機(jī)的總體結(jié)構(gòu)圖,對(duì)各個(gè)零件的布置有了初步設(shè)計(jì)并對(duì)阻尼裝置進(jìn)行的設(shè)計(jì)。
根據(jù)總體設(shè)計(jì)圖中的輸送機(jī)參數(shù)對(duì)阻尼裝置的制動(dòng)力進(jìn)行計(jì)算,然后根據(jù)制動(dòng)力對(duì)制動(dòng)輥進(jìn)行設(shè)計(jì),計(jì)算出輸送機(jī)貨物的阻尼,從而確定輸送機(jī)貨物的限速范圍。
在工作過程中,自己的疑問在老師和同學(xué)的幫助下,基本上都得到了解決。在以后的設(shè)計(jì)中將繼續(xù)查閱相關(guān)資料,參考現(xiàn)有的設(shè)備對(duì)裝配圖進(jìn)行優(yōu)化。同時(shí)繪制零件圖。
根據(jù)設(shè)計(jì)要求,在老師的指導(dǎo)下,最快最好的完成各項(xiàng)工作。
2012 年 05 月 28 日
指導(dǎo)教師評(píng)價(jià)意見
1.設(shè)計(jì)(論文)進(jìn)展情況評(píng)價(jià)
(基本完成計(jì)劃、部分完成計(jì)劃、沒有完成計(jì)劃)
2.學(xué)生工作態(tài)度情況評(píng)價(jià)
(認(rèn)真、一般、較差)
3.已完成設(shè)計(jì)(論文)質(zhì)量評(píng)價(jià)
(較好、一般、較差)
4.設(shè)計(jì)(論文)不足之處及改進(jìn)意見
指導(dǎo)教師簽字:
年 月 日
注:每名學(xué)生填寫一份,并由指導(dǎo)教師填寫意見、簽字后,返還學(xué)生歸檔。
本科畢業(yè)設(shè)計(jì)(論文)
題目 重力滾到輸送機(jī)阻尼裝置設(shè)計(jì)
學(xué)院名稱 機(jī)械與汽車工程學(xué)院
專業(yè)班級(jí) 機(jī)械08-2班
學(xué)生姓名 張淇翔
導(dǎo)師姓名 范維華
2012年 6 月 7 日
- 1 -
山 東 輕 工 業(yè) 學(xué) 院
畢業(yè)實(shí)習(xí)報(bào)告
院系名稱 機(jī)械與汽車工程學(xué)院
學(xué)生姓名 張淇翔
專業(yè)班級(jí) 機(jī)械08—2班
指導(dǎo)教師 范 維 華
二○一二 年 四 月 二十二 日
實(shí) 習(xí) 情 況 一 覽 表
時(shí)間
地 點(diǎn)
實(shí)習(xí)內(nèi)容(講座、參觀、車間工作、總結(jié)等)
指導(dǎo)教師
備注
3月中旬
濟(jì)南煙草
配送中心
參觀精準(zhǔn)分揀系統(tǒng)廠房
和儲(chǔ)藏?zé)煵莸膫}(cāng)庫(kù)
沈敏德
范維華
3月中旬
將軍集團(tuán)濟(jì)
南卷煙廠
參觀了卷包車間,里面有數(shù)臺(tái)生產(chǎn)速度為1000支/分鐘的卷煙機(jī)和400包/分鐘的包裝機(jī)。盡管在卷絲車間有數(shù)臺(tái)規(guī)模巨大的生產(chǎn)設(shè)備,然而所有設(shè)備都可以通過中央控制室來控制
沈敏德
范維華
一、實(shí)習(xí)目的
大學(xué)四年即將結(jié)束,接踵而來的是找工作,畢業(yè),就業(yè)。壓力是如此的巨大,因?yàn)槲覀兇髮W(xué)四年的學(xué)習(xí)并沒有給我們帶來實(shí)際的工作能力,也沒有絲毫的社會(huì)經(jīng)驗(yàn)。利用畢業(yè)前的這一段時(shí)間,學(xué)校組織我們?nèi)⒓恿诉@次的集體實(shí)習(xí),讓我們對(duì)社會(huì),對(duì)工作有些許的了解,以便畢業(yè)之后工作時(shí)不至于捉襟見肘。
1、將理論與實(shí)踐相結(jié)合
通過這次的畢業(yè)實(shí)習(xí),我們先后接觸與本專業(yè)相關(guān)的一些實(shí)際工作,對(duì)于工作所要求具備的專業(yè)理論知識(shí)和基本技能有個(gè)大體客觀的認(rèn)識(shí)。實(shí)習(xí)過程中,要求我們通過聽取公司產(chǎn)品方面的講座學(xué)會(huì)理論和實(shí)踐有機(jī)結(jié)合,將我們平日里學(xué)的知識(shí)有機(jī)的結(jié)合到實(shí)踐中,然后更好的理解書本上的理論知識(shí)
2、找到差距,盡快縮短差距
實(shí)習(xí)時(shí),我們會(huì)參觀一些有名企業(yè),期間公司負(fù)責(zé)人會(huì)給我們作講座,帶領(lǐng)我們參觀他們企業(yè)內(nèi)部的流程,員工工作的環(huán)境以及了解員工應(yīng)該具有的專業(yè)技能。通過觀察,我看到了他們這些企業(yè)所要求員工所具備的那種職業(yè)素質(zhì),專業(yè)技能。而從我們身上體現(xiàn)出來的卻只是稚氣未退的學(xué)生氣,我們之間的差距明顯很大,我們畢業(yè)盡快調(diào)整自己使自己成為一名于社會(huì)需要,于企業(yè)合格的人才。
3、讓自己盡快轉(zhuǎn)變?yōu)樯鐣?huì)人
我們是即將畢業(yè)踏入社會(huì)的大學(xué)生,學(xué)生時(shí)代的稚氣已不適合于社會(huì)。由一個(gè)學(xué)生到一個(gè)職業(yè)人員的轉(zhuǎn)變過程,要求我們學(xué)會(huì)獨(dú)立、成熟和堅(jiān)強(qiáng),踏入社會(huì)我們必須學(xué)會(huì)擔(dān)負(fù)責(zé)任,腳踏實(shí)地,消除自己原本的擔(dān)憂,努力工作每一天。這次實(shí)習(xí)就是為了讓我們明白工作人要 擁有該有的素質(zhì)和能力。
二、實(shí)習(xí)內(nèi)容
馬克思哲學(xué)告訴我們,實(shí)踐是檢驗(yàn)真理的唯一標(biāo)準(zhǔn)。在大學(xué)里,我們學(xué)習(xí)了很多的理論知識(shí),不過我們總覺得很空,這正是因?yàn)槿狈?shí)踐。實(shí)習(xí)正式將我們理論運(yùn)用至實(shí)際生活中的機(jī)會(huì)。我們要想成為對(duì)社會(huì)有用的人才,要想在畢業(yè)后就可以找個(gè)好工作,實(shí)現(xiàn)自己的人生價(jià)值,就要重視好在大學(xué)里的實(shí)習(xí)。同時(shí)實(shí)習(xí)是一次不可多得的集體活動(dòng)。平時(shí)在學(xué)校,除了上課,大家聚在一起的時(shí)間很少,缺乏生活上的專業(yè)上的必要交流,通過這次實(shí)習(xí)首先加強(qiáng)了同學(xué)們之間的凝聚力。
(一)將軍集團(tuán)濟(jì)南卷煙廠
將軍集團(tuán)濟(jì)南卷煙廠是國(guó)有大型企業(yè)。在特別人員的帶領(lǐng)下, 我們首先參觀了卷包車間,里面有數(shù)臺(tái)生產(chǎn)速度為1000支/分鐘的卷煙機(jī)和400包/分鐘的包裝機(jī)。卷煙機(jī)主要是將煙絲、濾棒和包裝紙卷在一起。在車間里,我們重點(diǎn)參觀了卷煙和包裝機(jī),一萬(wàn)多個(gè)零件組成的機(jī)構(gòu),高速運(yùn)轉(zhuǎn)著,卷接、包裝設(shè)備自動(dòng)化水平高。當(dāng)時(shí)有臺(tái)機(jī)器出現(xiàn)了問題,由于整套裝置有阻塞、夾條、掉條檢測(cè)控制剔除系統(tǒng)工人師傅們很容易的排除故障。在參觀中,我們注意到了卷煙廠高度自動(dòng)化的流水線和精確的質(zhì)量控制系統(tǒng)。當(dāng)煙葉從整包被分離后,就開始進(jìn)入加工階段。在經(jīng)過皮帶傳輸和振動(dòng)運(yùn)輸?shù)礁鱾€(gè)加工環(huán)節(jié)過程中,對(duì)流量有著嚴(yán)格的控制,皮帶上安裝有電子傳感器,能通過控制帶速來控制流量。盡管在卷絲車間有數(shù)臺(tái)規(guī)模巨大的生產(chǎn)設(shè)備,然而所有設(shè)備都可以通過中央控制室來控制。由于企業(yè)引入了現(xiàn)場(chǎng)總線,使得所有生產(chǎn)狀況都可以及時(shí)在中控室的電腦控制屏上顯示,包括動(dòng)力部門的能源控制。
在現(xiàn)場(chǎng),我們提出詢問了許多感興趣的問題,有關(guān)人員熱情細(xì)致地給予解釋,直到我們把整個(gè)工藝、生產(chǎn)流程了解為止。先進(jìn)的生產(chǎn)設(shè)備,有序的生產(chǎn)現(xiàn)場(chǎng),高素質(zhì)的操作員工,給我們留下了深刻的印象。卷包車間的卷接包、裝封箱、入庫(kù)全部實(shí)現(xiàn)了自動(dòng)化。經(jīng)技術(shù)人員介紹,整個(gè)卷煙的生產(chǎn)流程如下:投料→開包→切片→回槽(提溫加水) →儲(chǔ)存兩個(gè)小時(shí)左右→脫水→卷煙→包裝。
通過實(shí)習(xí)發(fā)現(xiàn)的不足:原機(jī)裝封箱機(jī)速度不高,只能一臺(tái)裝封箱機(jī)對(duì)應(yīng)一臺(tái)套卷包設(shè)備;二是離倉(cāng)庫(kù)比較遠(yuǎn),不利于輸送并且在輸送過程中易造成破損;設(shè)備多并且控制比較復(fù)雜,操作和修理維護(hù)都需要大量的人力物力。
(二) 濟(jì)南煙草配送中心
在本次主要對(duì)濟(jì)南煙草配送中心兩家單位進(jìn)行了詳細(xì)的實(shí)地的參觀和了解,著重對(duì)這家單位的物流配送體系,物流配送設(shè)備,在各個(gè)環(huán)節(jié)中所采用的現(xiàn)代化技術(shù)以及整個(gè)物流的資源配置系統(tǒng)進(jìn)行了詳盡的認(rèn)識(shí)和學(xué)習(xí),因?yàn)閮杉移髽I(yè)的設(shè)備與流程大體相近,現(xiàn)主要介紹濟(jì)南煙草配送中心。
濟(jì)南煙草配送中心隸屬于濟(jì)南煙草專賣局,濟(jì)南市煙草專賣局資本雄厚,在面對(duì)國(guó)際間激烈的煙草市場(chǎng)的發(fā)展競(jìng)爭(zhēng)下,積極采用先進(jìn)技術(shù),提高自己的信息化和自動(dòng)化建設(shè)。尤其是以濟(jì)南煙草配送中心是作為新型的現(xiàn)代物流來建設(shè),坐落于濟(jì)南高新區(qū),與齊魯軟件園毗鄰,尖端的環(huán)境優(yōu)勢(shì)使得濟(jì)南煙草物流在收發(fā)配送方面獨(dú)具優(yōu)勢(shì),同時(shí)濟(jì)南煙草物流中心通過網(wǎng)絡(luò)營(yíng)銷、倉(cāng)儲(chǔ)系統(tǒng)、分揀系統(tǒng)、線路優(yōu)化、GPS車輛監(jiān)控等信息系統(tǒng)技術(shù),使得濟(jì)南煙草物流中心的快速反應(yīng)令人吃驚,對(duì)濟(jì)南地區(qū)的煙草配送在整個(gè)省內(nèi)行業(yè)乃至全國(guó)位居前列。
在濟(jì)南煙草配送中心主要參觀的是蘭劍物流為濟(jì)南煙草配送中心和煙臺(tái)煙草配送中心設(shè)計(jì)的煙草的倉(cāng)儲(chǔ)系統(tǒng)、分揀系統(tǒng)和相關(guān)配送系統(tǒng)。在最開始的相關(guān)工作人員講解中我們了解到,煙草行業(yè)的競(jìng)爭(zhēng)已經(jīng)不再局限于國(guó)內(nèi)煙草企業(yè)的競(jìng)爭(zhēng),跨國(guó)煙草企業(yè)的競(jìng)爭(zhēng)壓力,讓中國(guó)煙草行業(yè)面臨巨大的挑戰(zhàn)。能否全面建立完善的煙草物流配送體系是煙草行業(yè)能否取勝的關(guān)鍵環(huán)節(jié),如何布局規(guī)劃配送中心的建設(shè)是煙草行業(yè)不得不去思考的問題。而此套物流方案解決了配送運(yùn)營(yíng)體系中的許多問題,實(shí)現(xiàn)了配送網(wǎng)點(diǎn)的合理布局,資源的優(yōu)化配置及時(shí)周轉(zhuǎn),提高了分揀的效率,大大降低了配送成本,總體上全面提升了煙草配送效率。電話訪銷、精準(zhǔn)分揀、及時(shí)配送,提高了服務(wù)質(zhì)量和顧客忠誠(chéng)度,減少了市場(chǎng)上非正規(guī)渠道卷煙的沖擊壓力,降低了物流成本。
根據(jù)老師和公司的安排流程,首先我們參觀了煙草倉(cāng)庫(kù)的存儲(chǔ)系統(tǒng)。根據(jù)老師解說,此煙草存儲(chǔ)所用的倉(cāng)庫(kù)是一個(gè)自動(dòng)化立體倉(cāng)庫(kù)。從貨物進(jìn)入,分為兩種方式,一種是較為傳統(tǒng)的傳送帶運(yùn)輸方式,但是效率仍然比人工快很多,用的比較多的是采取叉車托盤方式,整托盤煙草進(jìn)入,然后進(jìn)行倉(cāng)庫(kù)保管即入庫(kù)。入庫(kù)過程是放到傳送帶由電腦全程操作,然后經(jīng)由由堆垛機(jī),,然后通過工業(yè)計(jì)算機(jī)的指令發(fā)送到由操作人員預(yù)先設(shè)定相關(guān)程序,采用了RFID射頻識(shí)別技術(shù)可以讀取貨物的一切信息并將其分配到應(yīng)有的位置,堆垛機(jī)按以獲取的信息自動(dòng)將貨物準(zhǔn)確無誤放在應(yīng)在的位置。這種入庫(kù)工作流程幾乎是全自動(dòng)化,只需要很少的幾個(gè)操作人員進(jìn)行監(jiān)控和操作,而且效率很高,整個(gè)系統(tǒng)設(shè)計(jì)的全面合理,功能的密切統(tǒng)一和集中以及自動(dòng)化的程度之高,都給我了很大的震撼。
接下來我們又去了分揀區(qū)的流水線查看其工作流程,剛開始,還沒有運(yùn)作,只是聽講解,說這套系統(tǒng)屬于第三代煙草分揀系統(tǒng)(第四代也已經(jīng)研制完畢,尚未完善投入),分揀速度很快,以及精確的自動(dòng)化包裝處理,聽得我們?cè)评镬F里,因?yàn)槊織l線上工作的也就四五個(gè)人,到底搞不清到底是怎么分揀這么多煙草滿足濟(jì)南市這么多客戶的訂單,稍等了幾分鐘,分揀線開始運(yùn)作。根據(jù)一步步的流程,各種煙從不同的槽口被吐出,快速的經(jīng)過傳送帶,然后送到包裝臺(tái),快速的進(jìn)行包裝,然后電子顯示屏顯示下一個(gè)客戶的訂單數(shù)量,看似很簡(jiǎn)單的流程,但是能夠控制的這么好,而且很精確的控制各類的煙草所要出具的數(shù)量,這一系列流程的整合,大大的提高了分揀的效率和精確度。全部自動(dòng)一體化的完成,讓我深深感受到了現(xiàn)代化的信息系統(tǒng)所創(chuàng)造的價(jià)值。
最后關(guān)于煙草的配送系統(tǒng),由于GPS系統(tǒng)正在更新為3G,所以老師根據(jù)歷史資料進(jìn)行解說,經(jīng)過查資料了解到,從整個(gè)煙草配送體系功能來看,本系統(tǒng)的在運(yùn)輸方面,使用采用的電子地圖和GPS實(shí)時(shí)定位系統(tǒng),地圖上面標(biāo)明了根據(jù)各銷售點(diǎn)的位置而設(shè)計(jì)好的最優(yōu)配送路線以及貨車采用的GPS定位系統(tǒng),可準(zhǔn)確地了解每一輛貨車所在的位置及每次所消耗的時(shí)間,最終可準(zhǔn)確的落實(shí)每一天的工作效率。同時(shí)對(duì)濟(jì)南煙草運(yùn)輸線路的全面優(yōu)化,重新將濟(jì)南各個(gè)區(qū)域布局,減少各區(qū)間之間的疊加、沖突,使得交叉覆蓋面積最小交叉覆蓋率小于15%,路線得到更加合理的配置。物流信息,作為中樞神經(jīng)系統(tǒng)的物流信息在整個(gè)配送系統(tǒng)中起到的作用——計(jì)劃預(yù)測(cè)、動(dòng)態(tài)分析、及時(shí)提供市場(chǎng)動(dòng)態(tài)等相關(guān)內(nèi)容。濟(jì)南煙草配送信息這一塊做的比較到位,從計(jì)算機(jī)中能及時(shí)獲得相關(guān)的信息,為做出研究分析、制定相關(guān)策略提供了有力的保障。
本次實(shí)習(xí)總結(jié):通過這次實(shí)習(xí),我更深刻的認(rèn)識(shí)到物流這個(gè)概念的深度和廣度,以及在現(xiàn)實(shí)生活中,我們對(duì)物流的應(yīng)用的層面,我發(fā)現(xiàn)課本的理論知識(shí)在實(shí)際過程中運(yùn)用的很巧妙,因地制宜,靈活貫通給我了很大的啟示,也發(fā)覺了真正的實(shí)際操作中,我們對(duì)課本知識(shí)掌握的不夠扎實(shí),也不夠全面,更沒有系統(tǒng)的思維和考慮。所以,我要學(xué)習(xí)的東西還很多,要真正領(lǐng)會(huì)課本的理論知識(shí)以及運(yùn)用的方法和價(jià)值。
結(jié)論和建議:在濟(jì)南煙草中心,采用了現(xiàn)代信息化的設(shè)施和自動(dòng)化的整合系統(tǒng),在很大程度上降低人員的勞動(dòng)強(qiáng)度,節(jié)約生產(chǎn)成本,提高工作效率; 對(duì)于在煙草行業(yè)推廣應(yīng)用新興的物流技術(shù),降低物流成本、實(shí)現(xiàn)配送現(xiàn)代化管理起了推動(dòng)作用。然而在實(shí)際運(yùn)作中,完備齊全的自動(dòng)化系統(tǒng)會(huì)花費(fèi)很大資金,希望在系統(tǒng)的設(shè)計(jì)方面能加以改善以節(jié)約成本,同時(shí)注重成本和效能,達(dá)到性能最優(yōu)化,從而可以推廣到其他物流企業(yè),真正的做好我國(guó)物流行業(yè)的領(lǐng)頭羊。同時(shí)在做煙草的同時(shí),關(guān)于實(shí)地的配送運(yùn)輸問題上,建議與部分物流相關(guān)企業(yè)進(jìn)行合作,實(shí)現(xiàn)附帶運(yùn)輸,以增加附加值和利潤(rùn),同時(shí)可以降低成本。
3、 實(shí)習(xí)總結(jié)
畢業(yè)前安排這次畢業(yè)實(shí)習(xí)使我收獲很多。老師帶領(lǐng)我們參觀一些卷煙廠和物流中心公司還有知名企業(yè)-張?jiān)9荆钊氲礁鞴镜纳a(chǎn)車間觀看員工的工作環(huán)境、產(chǎn)品生產(chǎn)工藝和研發(fā)設(shè)計(jì)產(chǎn)品。每到一個(gè)公司,負(fù)責(zé)人都會(huì)很詳細(xì)地給我們介紹公司產(chǎn)品以及它們利用的基本原理。這次畢業(yè)實(shí)習(xí)讓我了解專業(yè)有關(guān)的工作,對(duì)之前的畢業(yè)后從事的工作存在的疑惑也解除了。
在學(xué)校里,我們學(xué)習(xí)專業(yè)基本知識(shí),缺乏專業(yè)實(shí)踐能力的鍛煉,離現(xiàn)實(shí)社會(huì)所需專業(yè)人才還有很大的差距,一直抱怨學(xué)校里學(xué)到的知識(shí)沒有實(shí)際利用價(jià)值,其實(shí)這都是借口,進(jìn)入大學(xué),我們首先學(xué)會(huì)獨(dú)立自學(xué),然而我們這點(diǎn)沒有做好,更沒有人限制我們時(shí)間,是我們沒有利用好它。盡管實(shí)驗(yàn)室條件有限,那些都是客觀理由。“活到老學(xué)到老”這句話永遠(yuǎn)具有現(xiàn)實(shí)意思。就像那位引導(dǎo)員說的,別把自己想象的太優(yōu)秀,真正踏入社會(huì),你會(huì)發(fā)現(xiàn)很多問題。
畢業(yè)實(shí)習(xí)給我們畢業(yè)后的工作打下了一定的基礎(chǔ),讓我們懂得了工作跟學(xué)習(xí)兩碼事。馬上要踏入社會(huì),進(jìn)入工作崗位了,一個(gè)人需要迅速轉(zhuǎn)變角色,適應(yīng)社會(huì),去創(chuàng)造價(jià)值,把專業(yè)知識(shí)運(yùn)用出來,并在工作上不斷學(xué)習(xí),不斷創(chuàng)新。畢業(yè)實(shí)習(xí)讓我們學(xué)到了很多,感謝學(xué)校,感謝老師給予我們這次機(jī)會(huì)。
這學(xué)期的實(shí)習(xí)的實(shí)習(xí)使我對(duì)自己的專業(yè)有了直接具體的認(rèn)識(shí),在親身經(jīng)歷生產(chǎn)過程以前對(duì)機(jī)械這一行業(yè)的了解僅僅限于理論知識(shí),對(duì)各種機(jī)床和生產(chǎn)設(shè)備也沒有接觸太多。實(shí)習(xí)之后,可以大致了解到現(xiàn)行的機(jī)械行業(yè)的運(yùn)行情況,以及現(xiàn)在的制造業(yè)發(fā)展的動(dòng)向。
指導(dǎo)教師評(píng)語(yǔ):
實(shí)習(xí)成績(jī):
指導(dǎo)教師: 年 月 日
山 東 輕 工 業(yè) 學(xué) 院
畢 業(yè) 設(shè) 計(jì)(論 文)任 務(wù) 書
機(jī)械與汽車工程學(xué)院 2008 級(jí) 機(jī)械設(shè)計(jì)制造及其自動(dòng)化專業(yè) 姓名 張淇翔
題目 重力滾道輸送機(jī)阻尼裝置設(shè)計(jì)
主要內(nèi)容、基本要求、主要參考資料等:
1. 主要內(nèi)容:本設(shè)計(jì)任務(wù)是根據(jù)部分影象資料和網(wǎng)上查閱地資料進(jìn)行研發(fā)工作,這次設(shè)計(jì)主要根據(jù)現(xiàn)代物流的要求,宗合考濾不同地作業(yè)項(xiàng)目,不同附件的按裝結(jié)構(gòu),對(duì)重力滾道輸送機(jī)阻尼裝置設(shè)計(jì)進(jìn)行總體設(shè)計(jì)。要求制動(dòng)可靠,能有效的防止輸送物下滑過快,配件具有一定的通用性,技術(shù)先進(jìn),結(jié)構(gòu)緊湊。此設(shè)計(jì)國(guó)內(nèi)尚無此種類型的定型產(chǎn)品,此設(shè)計(jì)國(guó)內(nèi)尚無此種類型的定型產(chǎn)品,屬開發(fā)設(shè)計(jì)。
2. 基本要求:對(duì)現(xiàn)代物流系統(tǒng)和重力滾道輸送機(jī)有基本了解,對(duì)阻尼裝置的工作原理有全面細(xì)致的理解,結(jié)合機(jī)械與物流等相關(guān)知識(shí)進(jìn)行設(shè)計(jì)。完成重力滾道輸送機(jī)阻尼裝置設(shè)計(jì)圖紙,寫出設(shè)計(jì)論文。
3. 主要參考資料:設(shè)計(jì)手冊(cè),部分重力滾道輸送機(jī)圖片資料,現(xiàn)代物流資料及機(jī)械相關(guān)資料。
完成期限:自 2012 年 3 月 15 日至 2012年 6 月 15 日
指導(dǎo)教師: 范維 華 教研室主任:
學(xué)院院長(zhǎng): 年 月 日
畢業(yè)設(shè)計(jì)(論文)開題報(bào)告
課題名稱
重力滾道輸送機(jī)阻尼裝置設(shè)計(jì)
課題類型
導(dǎo)師姓名
學(xué)生姓名
學(xué) 號(hào)
專業(yè)班級(jí)
一、 設(shè)計(jì)依據(jù)與目的
1、 物料搬運(yùn)現(xiàn)狀
物料搬運(yùn)是保證物流系統(tǒng)暢通有效運(yùn)行的一個(gè)重要環(huán)節(jié),因此,完成物料搬運(yùn)的輸送機(jī)械,也就成為物流系統(tǒng)設(shè)計(jì)規(guī)劃人員重點(diǎn)關(guān)注的項(xiàng)目。在固定路徑的運(yùn)送中(如生產(chǎn)物流中,制品在各工序間的流動(dòng),倉(cāng)儲(chǔ)系統(tǒng)中貨物的手法以及配送中心的揀貨發(fā)貨等),大都采用輥筒、皮帶或鏈條等型式的輸送機(jī)械,即單元負(fù)載輸送機(jī),其中一滾筒型式較為常見。
2、 滾筒式輸送機(jī)分類
輥筒式輸送機(jī)根據(jù)其動(dòng)力源不同可分為兩類。一類是動(dòng)力式,即輥筒由動(dòng)力帶動(dòng)旋轉(zhuǎn)。通常以電動(dòng)機(jī)為原動(dòng)力。另一類為重力式輥筒輸送機(jī)。這類輸送機(jī)沒有動(dòng)力,靠將輥道傾斜成一個(gè)適當(dāng)?shù)慕嵌龋伒郎媳惠斔偷奈矬w在重力作用下自行下滑,因不需動(dòng)力,結(jié)構(gòu)簡(jiǎn)單等優(yōu)點(diǎn),在短距離物料輸送中得到廣泛應(yīng)用。
3、 設(shè)計(jì)目的
由于重力的作用,在重力滾道輸送機(jī)上,輸送物會(huì)愈滑愈快,產(chǎn)生輸送物之間的相互碰撞擠壓,使輸送物損壞,甚至崩落或損傷人、機(jī)。為了避免此類事故,所以需要設(shè)計(jì)一個(gè)阻尼裝置,即制動(dòng)輥。
二、 設(shè)計(jì)內(nèi)容
根據(jù)重力滾道輸送機(jī)發(fā)展的需要,根據(jù)客戶的實(shí)際條件的需求,結(jié)合機(jī)械技術(shù),參考、計(jì)算、分析現(xiàn)有的重力滾道輸送機(jī),設(shè)計(jì)出一套符合設(shè)計(jì)要求及社會(huì)需求的方案。
三、 設(shè)計(jì)方法及及技術(shù)路線
1、設(shè)計(jì)方法
(1)選擇設(shè)計(jì)題目,仔細(xì)聽取老師所講的內(nèi)容,認(rèn)真思考一下。
(2)上網(wǎng) 、去圖書館查閱資料,弄明白自己到底需要做什么。
(3)根據(jù)所收集的資料作出設(shè)計(jì)方案。
(4)經(jīng)過計(jì)算設(shè)計(jì)的數(shù)據(jù),畫出設(shè)計(jì)裝配圖、零件圖。
(5)整理資料,寫設(shè)計(jì)說明書,準(zhǔn)備答辯。
2、技術(shù)路線
我所設(shè)計(jì)的重力滾道輸送機(jī)阻尼裝置是一種制動(dòng)輥裝置,它能根據(jù)輸送機(jī)的速度與給定的速度進(jìn)行對(duì)比,然后進(jìn)行有效的調(diào)整。
3、參考文獻(xiàn)
1.濮良貴、紀(jì)明剛主編?!稒C(jī)械設(shè)計(jì)(第八版)》。高等教育出版社
2.孫恒、陳作模、葛文杰主編?!稒C(jī)械原理(第七版)》。高等教育出版社
3.申綱領(lǐng)主編?!冬F(xiàn)代物流管理》。北京大學(xué)出版社
四、 設(shè)計(jì)安排
3月中旬:領(lǐng)取設(shè)計(jì)題目
3月中旬到4月初:查閱相關(guān)資料,初步提出設(shè)計(jì)方案
4月6日到10日:進(jìn)行畢業(yè)實(shí)習(xí)
4月下旬:撰寫開題報(bào)告和實(shí)習(xí)報(bào)告,并提出設(shè)計(jì)方案
4月下旬到5月初:進(jìn)行結(jié)構(gòu)方案設(shè)計(jì),繪制裝配草圖
5月初到六月初:進(jìn)行設(shè)計(jì)計(jì)算,對(duì)方案中涉及到的各零部件進(jìn)行選擇并對(duì)其剛度、強(qiáng)度等進(jìn)行核算,并繪制零件圖、裝配圖
6月上旬:整理、編寫任務(wù)說明書,并打印零件圖、裝配圖、任務(wù)說明書,準(zhǔn)備畢業(yè)答辯
五、 設(shè)計(jì)總結(jié)
指導(dǎo)教師意見:
指導(dǎo)教師: 年 月 日
目 錄
摘要 …………………………………………………………………1
第1章 緒 論 1
1.1 現(xiàn)代重力輥道輸送機(jī)的概況 1
1.2 重力輥道輸送機(jī)阻尼裝置現(xiàn)狀...............................................................2
1.3 主要內(nèi)容及技術(shù)指標(biāo) 4
第2章 總體方案的設(shè)計(jì) 6
2.1重力滾道輸送機(jī)阻尼裝置的工作原理 6
2.2方案的選擇 6
2.3主要工作部件的設(shè)計(jì) 7
第3章 總體配置的確定 8
3.1阻尼輥筒的整體設(shè)計(jì) 8
3.2傳動(dòng)系統(tǒng)設(shè)計(jì) 8
3.3傳動(dòng)裝置 9
3.4制動(dòng)塊的設(shè)計(jì) 9
第4章 阻尼輥筒的整體設(shè)計(jì) 10
第5章 制動(dòng)塊的設(shè)計(jì)......................................................................10
5.1制動(dòng)塊的受力分析.............................................................................11
5.2計(jì)算摩擦快所受的擠壓力Fj............................................................11
5.3求離心力FL.......................................................................................11
5.4計(jì)算擺塊的有關(guān)參數(shù)........................................................................12
5.5計(jì)算阻尼輥筒內(nèi)部的傳動(dòng)比i..........................................................13
第6章 傳動(dòng)部分設(shè)計(jì) 14
6.1初定Vt、D2和i.......................................................................................14
6.2確定齒輪的模數(shù)和齒數(shù) 14
6.3確定輥?zhàn)拥钠渌Y(jié)構(gòu)參數(shù) 15
第7章 內(nèi)置式阻尼輥筒的保養(yǎng)、使用、調(diào)整及修復(fù) 15
7.1每日技術(shù)保養(yǎng) 15
7.2傳動(dòng)裝置的使用和調(diào)整 16
7.3阻尼輥筒的保管 16
7.4工作部件損壞的修復(fù)和調(diào)整 16
全文總結(jié)與展望 17
總結(jié) 17
課題展望 17
致謝 18
參考文獻(xiàn) 19
1
摘 要
重力式滾道輸送機(jī)因其不需動(dòng)力,結(jié)構(gòu)簡(jiǎn)單等優(yōu)點(diǎn),在短距離物料輸送中得到廣泛的應(yīng)用。重力式滾道輸送機(jī)是利用輸送物自身的重力沿斜面下滑進(jìn)行輸送的。由于重力的作用,輸送物會(huì)愈滑愈快,產(chǎn)生輸送物之間的互相碰撞擠壓,使輸送物損壞,甚至崩落或損傷人、機(jī)。在輸送過程中,也可能由于輸送機(jī)自身的原因,如輥筒變形過大,貨物底部或托盤底部的粗糙或不規(guī)則,使其在輸送過程中停止不動(dòng),無法再起動(dòng)重新下滑,這時(shí)需要人力協(xié)助推動(dòng)恢復(fù)下滑。
為了達(dá)到設(shè)計(jì)要求,根據(jù)較普遍的重力式滾道輸送機(jī),本設(shè)計(jì)阻尼裝置主要采用內(nèi)置裝置。這在很大程度上節(jié)省了人力,而且在結(jié)構(gòu)上比傳統(tǒng)設(shè)計(jì)方法更為合理。經(jīng)計(jì)算、校核,該裝置符合設(shè)計(jì)要求,適合作為重力輥道輸送機(jī)阻尼裝置。
關(guān)鍵詞:重力式滾道輸送機(jī);阻尼裝置;
Abstract
Gravity groove conveyor because its does not need to power, simple structure, etc, and in short material conveying widely applied.Gravity groove conveyor belt conveyor is using its own gravity conveying things along the decline in transmission cant.Because the pull of gravity, conveying the slippery thing will soon, produce conveying the each other between things collision extruding, make things conveying damage, even caving man, machine or injury. In the course of transmission for, also may be due to the conveyor their own reasons, such as the rollers deformation is too large, the bottom tray or at the bottom of the rough or irregular, in the conveying process is at a standstill, can't start to decline, at this moment need to promote human help restore to slide.
In order to meet the design requirements, according to universal gravity groove conveyor, this design damping device is mainly using built-in device. This is largely save manpower, and on the structure more reasonable than the traditional design method.The calculation, checking, this device comply with the design requirements, suitable for as gravity roller conveyor damping device.
Key words: Gravity groove conveyor;Damping device。
III / 19
4 / 19
在工程設(shè)計(jì)研究13(2002)55±64
工業(yè)部10.1007 / s00163 - 001 -0007- 4
針對(duì)理想的機(jī)械工程設(shè)計(jì)支持系統(tǒng)的研究
大衛(wèi)G.Ullman
摘要:本文詳細(xì)介紹了在開發(fā)進(jìn)展理想的機(jī)械設(shè)計(jì)的支持系統(tǒng)。它試圖填補(bǔ)這個(gè)工程師的需求和目前市面上的計(jì)算機(jī)輔助設(shè)計(jì)(CAD)系統(tǒng)之間的差距。自從強(qiáng)調(diào)了計(jì)算機(jī)輔助設(shè)計(jì)(CAD) 這個(gè)術(shù)語(yǔ),電腦已成為人類設(shè)計(jì)師的強(qiáng)有力的助手,這篇文章的內(nèi)容是設(shè)計(jì)師的的中心任務(wù)。它緊緊根據(jù)設(shè)計(jì)師所做的項(xiàng)目和他們開發(fā)的信號(hào)系統(tǒng)項(xiàng)目的類型。17項(xiàng)關(guān)于理想機(jī)械設(shè)計(jì)的支持系統(tǒng)在這里被一一列舉出來。這些先進(jìn)的信號(hào)系統(tǒng)直接應(yīng)用于設(shè)計(jì)過程和實(shí)際應(yīng)用與發(fā)展中,對(duì)于這十七項(xiàng)中的任何一項(xiàng),根據(jù)目前他們的發(fā)展情況,他們是目前最先進(jìn)也是有很大未來發(fā)展空間的研究項(xiàng)目。
關(guān)鍵詞:機(jī)械工程設(shè)計(jì)、計(jì)算機(jī)輔助設(shè)計(jì)(CAD),支持系統(tǒng)。
1
介紹
本文總結(jié)了理想機(jī)械工程設(shè)計(jì)支持系統(tǒng)的發(fā)展進(jìn)程。近30年來,計(jì)算機(jī)輔助設(shè)計(jì)系統(tǒng)已經(jīng)被他們的開發(fā)者作為支持系統(tǒng)工程設(shè)計(jì),發(fā)展產(chǎn)品的系統(tǒng)加以吹捧。這是說計(jì)算機(jī)輔助設(shè)計(jì)(CAD)系統(tǒng)在關(guān)于怎樣在工作場(chǎng)所使設(shè)計(jì)得以實(shí)現(xiàn)方面有重大的影響…,令人驚訝的是,很少有關(guān)于這個(gè)系統(tǒng)的對(duì)設(shè)計(jì)者和最終產(chǎn)品方面影響的正式研究。這篇文章介紹了一種討論這些效應(yīng)結(jié)構(gòu)。
2000年2月11日收到:/2000年12月9日校稿:
2001年9月19日接受: /2001年11月13在線發(fā)表
2001年Springer-Verlag
D.G.Ullman
俄勒岡州立大學(xué)機(jī)械設(shè)計(jì)方面的榮譽(yù)退休教授,機(jī)械工程研究所碩士論文。具有較強(qiáng)的權(quán)威性性公司的董事長(zhǎng),Corvallis大街800號(hào),美國(guó)俄勒岡州97330。
電子郵件:ullman@robustdecisions.com:
本文由Autodesk資助;但是, 聲明這些意見和結(jié)論的作者主要是基于他的工作。
最近,并被認(rèn)為是徹底的,全身心投入此項(xiàng)尖端研究的學(xué)者只有八個(gè),他們大多集中在二維 [1,15,17,18,22,23,24,25]。作者沒有發(fā)現(xiàn)他們關(guān)于影響參數(shù)系統(tǒng)的研究性文章被出版。
在這樣做的同時(shí),他們總結(jié)了目前已知的和需要的研究東西。最后,探討了計(jì)算機(jī)輔助設(shè)計(jì)(CAD)系統(tǒng)發(fā)展來支持增加用于開發(fā)的產(chǎn)品活動(dòng)部分。
這個(gè)學(xué)期的計(jì)算機(jī)輔助設(shè)計(jì)(CAD)強(qiáng)調(diào)計(jì)算機(jī)對(duì)于人類的設(shè)計(jì)師是一種援助,所以本文的主旨是中心設(shè)計(jì)者。它是根據(jù)這個(gè)活動(dòng)緊緊依賴這個(gè)活動(dòng)的設(shè)計(jì)師和他們開發(fā)的信息系統(tǒng)執(zhí)行。在許多方面,這是以前發(fā)表的兩個(gè)文件的一個(gè)更新(“繪制圖紙?jiān)跈C(jī)械設(shè)計(jì)過程中的重要性”和“設(shè)計(jì)的發(fā)展史存在的問題、設(shè)計(jì)合理性以及設(shè)計(jì)意向系統(tǒng)”)。 最近的一些文章提出13個(gè)突出的問題需要解決去實(shí)現(xiàn)并且提出了一種去改進(jìn)設(shè)計(jì)過程和有此引起的設(shè)計(jì)信息潛在的工程設(shè)計(jì)的疑問。
這第一筆由基金會(huì)出資進(jìn)行研究研究的論文是有五個(gè)具有不同的背景和經(jīng)驗(yàn)的機(jī)械設(shè)計(jì)工程師發(fā)表的。他們每個(gè)人都會(huì)給于關(guān)于其中一兩項(xiàng)的詳細(xì)說明書,但是實(shí)際的機(jī)械設(shè)計(jì)中的問題的還是在現(xiàn)實(shí)的實(shí)踐中遇到。當(dāng)工程師們正著手于解決問題時(shí),他們被強(qiáng)烈的要求去思考解決辦法。他們的口頭報(bào)告,圖紙,手勢(shì)被錄像和錄音大約能夠持續(xù)6到10 小時(shí)。根據(jù)被謄寫的這些錄音資料數(shù)據(jù)獲得一個(gè)關(guān)于這次設(shè)計(jì)會(huì)議的草案。每一個(gè)設(shè)計(jì)者都在他們解決問題的方法中繪制了幾張圖紙加以說明。所有的這些都是在圖紙上。計(jì)算機(jī)輔助設(shè)計(jì)(CAD)系統(tǒng)沒有被用于研究,因?yàn)闆]有設(shè)計(jì)者在他們的日常設(shè)計(jì)中使用計(jì)算機(jī)輔助設(shè)計(jì)(CAD)它的使用對(duì)一個(gè)已經(jīng)復(fù)雜的實(shí)驗(yàn)來說會(huì)增加勞動(dòng)強(qiáng)度。
根據(jù)長(zhǎng)達(dá)40多個(gè)小時(shí)的數(shù)據(jù)顯示,15節(jié)關(guān)于每門科目的概念、布局、詳細(xì)的典型設(shè)計(jì)被精選出來。這個(gè)草擬數(shù)據(jù)中其中的15個(gè)章節(jié)涵蓋了這些數(shù)據(jù)的174數(shù)據(jù)單元。通過總結(jié)分析觀測(cè)結(jié)果得出結(jié)論繪制成圖紙并將將之運(yùn)用于以下幾個(gè)方面:
1、檔案的幾何形態(tài)設(shè)計(jì)的
2、設(shè)計(jì)師之間和設(shè)計(jì)師和生產(chǎn)人員之間的思想交流
3、作為一種分析工具,通常, 不確定的尺寸和圖上的公差進(jìn)行開發(fā)
4、模擬的設(shè)計(jì)
5、作為一個(gè)完整性檢查者,作為草圖或者其他正在繪制中的圖紙剩下的設(shè)計(jì)細(xì)節(jié),這些對(duì)于設(shè)計(jì)師來說變得清晰。實(shí)際上,幫助建立一個(gè)完成剩下設(shè)計(jì)任務(wù)的議程
6、作為一個(gè)設(shè)計(jì)師的短期記憶的延伸。設(shè)計(jì)師往往無意識(shí)地使用草圖幫助他們記得的他們可能忘記的想法。
1990年的圖紙?jiān)俅伪话l(fā)現(xiàn)并且是支持證明這些這個(gè)說法。此外,雖然受試者不使用計(jì)算機(jī)輔助設(shè)計(jì)(CAD)系統(tǒng),但是結(jié)果卻表明:
1、計(jì)算機(jī)輔助設(shè)計(jì)(CAD)系統(tǒng)必須允許草圖的輸入。
2、計(jì)算機(jī)輔助設(shè)計(jì)(CAD)系統(tǒng)必須考慮到設(shè)計(jì)師使用的多種的接口界面。這雖然不意味著更多的方法去定義一個(gè)交際圈,但是必須去尋找一個(gè)滿足設(shè)計(jì)者需求的接口與計(jì)算機(jī)輔助設(shè)計(jì)(CAD)上的圖像相交流。
3、計(jì)算機(jī)輔助設(shè)計(jì)(CAD)必須能夠識(shí)別域相關(guān)的因素及完成他們的實(shí)體。
4、CAD工具需要能夠管理約束(甚至)摘要和功能的限制)并且確保他們的滿意,因?yàn)檫@是明顯的,人類的設(shè)計(jì)師在對(duì)他的認(rèn)知能力是有限。因此這篇文章表明,計(jì)算機(jī)輔助設(shè)計(jì)(CAD)系統(tǒng)已經(jīng)成熟了并指出,至少在某種程度上有以上四種結(jié)論。然而,即使最新的系統(tǒng)是和理想的機(jī)械工程設(shè)計(jì)支持系統(tǒng)之間仍有很大的差距。這篇文章對(duì)最理想的系統(tǒng)被描述并對(duì)對(duì)其進(jìn)展進(jìn)行了討論。
2
一個(gè)模型設(shè)計(jì)問題的解決
對(duì)設(shè)計(jì)者來說或許在將來的某天能夠戴上承載他(她)們理想和發(fā)展一種硬件陳述的“理想的帽子”。關(guān)于認(rèn)知過程、計(jì)算機(jī)輔助設(shè)計(jì)(CAD),和快速成型的研究正在它的領(lǐng)域進(jìn)行。這種現(xiàn)狀意味這我們可以在我們頭上陳述足夠好的可擔(dān)保的硬件將被開發(fā)出的概念。我們還可以假想計(jì)算機(jī)輔助設(shè)計(jì)(CAD)系統(tǒng)已經(jīng)足夠先進(jìn),能夠很好的承載我們的想法和處理好零件和總體的發(fā)展變化。計(jì)算機(jī)輔助設(shè)計(jì)(CAD)系統(tǒng)的發(fā)展需要的到設(shè)計(jì)者認(rèn)知工作的理解。只有這樣想法設(shè)想和表達(dá)陳述直接的互通才有可能。
所以去探究關(guān)于這個(gè)環(huán)節(jié)已知的知識(shí),考慮人類問題的解決者和用數(shù)字表示的外部環(huán)境直接的關(guān)系是非常重要的。這組數(shù)據(jù)是基于紐厄爾和西蒙對(duì)模型的研究并被稱為數(shù)字處理信息系統(tǒng)(IPS)。這些數(shù)據(jù)圖表是關(guān)于設(shè)計(jì)信息的產(chǎn)生和儲(chǔ)存的一個(gè)簡(jiǎn)單的“地圖”。這些圖標(biāo)同時(shí)也展示了一個(gè)內(nèi)部的,人類解決問題的環(huán)境(設(shè)計(jì)者的內(nèi)心)和外部環(huán)境(設(shè)計(jì)者思想外的客觀環(huán)境)。對(duì)于設(shè)計(jì)師來說,兩個(gè)位置對(duì)應(yīng)的是兩種不同類型的記憶:短期記憶(STM)和長(zhǎng)期記憶(LTM)。設(shè)計(jì)師外部的記憶方法有很多,有許多“設(shè)計(jì)存儲(chǔ)地點(diǎn)”包括圖形表示法、媒體例如:紙張和CAD工具,以及其它媒體,如:文本筆記、手冊(cè)和各位同仁。每種記憶方式都有它運(yùn)用于實(shí)際設(shè)計(jì)場(chǎng)合的背景和方法。短期記憶(STM)和長(zhǎng)期記憶(LTM)特征細(xì)節(jié)是基于紐尼爾和西門的思維模型。 它的延伸已經(jīng)被制成視覺圖片以及他的影響已被編碼。人們必須認(rèn)識(shí)到這個(gè)模型在這所包含的內(nèi)容雖然不完全同意認(rèn)知心理學(xué),但是他們足夠安全提供為討論CAD在機(jī)械設(shè)計(jì)中的作用討論依據(jù)。
2.1
短期記憶
短期記憶是非??觳⑶覐?qiáng)大的。短期記憶的內(nèi)容是我們意識(shí)到信息,也就是說,我們的有意識(shí)的心智。所有的設(shè)計(jì)操作(例如,視覺感知和圖紙創(chuàng)作)是基于短期記憶(STM)的信息。不幸的是,STM容量能力有限。研究表明,它是限于大約七個(gè)認(rèn)知單位或者大量的信息。在設(shè)計(jì)中,這些碎片是視覺圖像信息的形式能信息、事宜的心理模式以及在CAD中表示想法的步驟,或者其他離散的信息碎片。雖然短期記憶的容量的有限,但它是一種處理時(shí)間僅是100毫秒的快速處理器。
2.2
長(zhǎng)期記憶
另一方面,長(zhǎng)期記憶有本質(zhì)上的無限容量,但是進(jìn)入長(zhǎng)期記憶的通路也慢了。進(jìn)入長(zhǎng)期記憶的通道也不是直接的。記憶也必須是一些提示或是基于短期記憶的信息檢索策略引發(fā)。在設(shè)計(jì)中,有一部分內(nèi)容被儲(chǔ)存在長(zhǎng)期記憶中。那些有相對(duì)比較簡(jiǎn)單的線索供引發(fā)記憶,因?yàn)?在任何時(shí)候,目前重要的設(shè)計(jì)部分都是在STM中并能充當(dāng)長(zhǎng)期記憶中的知識(shí)思想的指針。
23
外部環(huán)境,
在這個(gè)試驗(yàn)(1990年)中,很明顯許多繪畫行為不習(xí)慣于用文字記載設(shè)計(jì)過程中的結(jié)果。
但是繪制本省就是設(shè)計(jì)活動(dòng)的一部分。如果這個(gè)畫表可以將他們所做的這些呈現(xiàn)在他們腦海中,他們就可以按他們腦海中呈現(xiàn)的這樣做而不用做草圖,筆記和在紙上計(jì)算。因此,我們可以得出的外部環(huán)境常被用作長(zhǎng)期記憶和短期記憶的延伸。在外部環(huán)境中運(yùn)用媒體來提高設(shè)計(jì)者的認(rèn)識(shí)能力是至關(guān)重要的。區(qū)分開媒體和人類的認(rèn)知之間的關(guān)系密不密切是這篇文章的一個(gè)目標(biāo)。本文所采用的方法首先是描述信息處理的類型,然后討論設(shè)計(jì)師由外部環(huán)境影響所作出的舉動(dòng)。這些信息的類型和舉動(dòng)對(duì)于理想的系統(tǒng)能力來說是成熟的。每節(jié)以最理想的工程設(shè)計(jì)支持系統(tǒng)應(yīng)該具有怎樣的功能為內(nèi)容開始。其余次要的信息遵循這些內(nèi)容.其次是關(guān)于記事本、二維CAD系統(tǒng),固體模型系統(tǒng)、參數(shù)系統(tǒng),以及其他支持工具怎樣滿足理想要求的描述。這樣使各分部得到改進(jìn)的機(jī)會(huì)。
Toward the ideal mechanical engineering design support system
David G.Ullman
Abstract This paper details the progress toward the development oftheidealmechanical engineering design support system.It attempts to look at the gap between the needs of a mechanicalengineerandwhatis currently available onCAD systems Since the tern:CAD emphasizes that the computer is an aid to the human designer,this paper is designer centric it is based heavi~on the activities performed by designers and the types ofinformation developed by then:Seventeen goals for the ideal mechanical design support system are listed These are directed at the types ofinfor mation developed during the design process and the activ ities used to develop them For each of the seventeen,background information,the current state of the art,and opportunities for future development are itemized
Keywords Mechanical engineering design,CAD,Support system
1
Introduction
This paper summarizes the progress made toward the development of the ideal mechanical engineering design support system For nearly 30 years,computer aided de sign(CAD)systems have been touted by their developers as systems that support engineering designers developing products CAD systems have had a major impact on how design is accomplished in the workplace This being said,there is amazingly little ibrmal research on the effects of these systems on the designers and on the final products’This paper presents a structure for discussing these effects
In doing so、lt summarizes what is known and what needs co be studied Finally、it discusses how CAD systems have evoh,edto supportincreasingportions ofthe activitiesthat are used to develop products.
The term CAD emphasizes that the computer ls an aid to the human designer,so this paper is designer centric it is based heavily on the activities pertbrmed by designers and the types ofintbrmation developed by them in many ways,this is an update of two earlier papers,‘‘The importance of drawing in the mechanical design process”[29 J and“issues critical to the development of design history,design ratio nale and design intent systems”【311 The latter paper developed 13 outstanding issues that needed to be resolvedto realize the capture and query ofengineering design intormation as a potential lor lmprovmg the design process
and the reuse ofdesign Intormation.
The tbundation for the first paper was the study of the marks made on paper by nve mechanical design engineers of varying backgrounds and experience They were each given the initial specifications tbr one of two t~irly simple, yet realistic,mechanical design problems taken from professional practice The engineers were requested to think aloud as they soh,ed the problems Their verbal reports、drawings,and gestures were video and audio taped for aperiod of6 10 h The taped data were then transcribed to obtain a‘‘protocol”of the design session Each designer made numerous drawings during his or her solution of the problem A11 0fthesewere on paper CAD systemswere not usedinthe studgbecausenone ofthedesigners usedCADln their daily practice,and its use would have added another variable to an already complex experiment.
From the more than 40 h ofdata taken,15 sections were selected that represented typical conceptual,layout,detail and selection design for each subject The 15 sections of protocol data consisted of 174 rain of data The data were analyzed to explore the observations that drawings are
usedto:
1 Archive the geometric torm of the design
2 Communicate ldeas between designers and between the designers and manufacturing personnel
3 Act as an analysis tool Often,missing dimensions and tolerances are calculated on the drawing as it ls developed
4 Simulate the design
5 Serve as a completeness checker As sketches or other drawings are being made,the details left to be designed become apparent to the designer This,in ett)ct,helps establish an agenda of design tasks leL to accomplish
6 Act as an extension of the designer’s short term memory Designers often unconsciouslv make sketches to help them remember ldeas that they might otherwise torget
The 1990 paper refined and supported these observa tions AdditionalIv,although the subiects did not use CAD systems,the resuhs suggested that:
1 CAD systerns nl[ist allow tbr sketching lnput
2 CAD systerns nlust allow for a variety of Interfaces tbr the designer This does not mean more ways to define a circle、but an eftort to match the interface and the im age on the CAD system to that needed by the designer
3 CAD systems iiltlSt recognize domain dependent features and treat them as entities
4 CAD tools need to be able to manage constraints(even abstract and tkmctional constraints)and ensure their satistaction、as it is evident that human designers are cognitively limited in this ability
Since that paper was written,CAD systerns have matured and have addressed、at least to some degree、all南ur of the conclusions iIowever,even the most recent systems are a ong way tbom the ideal mechanical engineering design support system In this paper,the ideal system will be described and progress toward this ldeal discussed
2
A model of design problem solving
it may someday be possible for a designer to put on a ‘‘thinking cap”that can take his or her thoughts and de elop a hardware reDresen【atlon Research on under standing cognitive processes,CAD,and rapid prototyping ls certainly moving ln that direction This ideal implies that we can tbrmtflate concepts Jn our heads that are sumciently well tormed to warrant hardware It also as sumes that CAD systems are suflicientlg developed to take our thoughts and manage the evolution of parts and as semblies CAD system development will require an tin derstanding of the cognitive workings of designers so that the transition tbom thought to representation is possible
To explore what ls known about this link、consider the relationship between the human problem soh,er and the external environment shown in Fig 1 This figure ls based on the model developed bv Newell and Simon『20l and ls called the information processing system(IPS)The figure is a simple‘‘map’’ofwhere information about the design is developed and stored The figure shows an internal,human problem solving environment(inside the mind of the designer)and an external environment(outside the mind of the designer)Within the designer,two locations correspond to the two different kinds of memory:short term memory(STM)and long term memory(LTM) External to the designer,there are many‘‘design storage locations”including graphical representation media such as pieces of paper and CAD tools,as well as other media such as textual notes,handbooks,and colleagues Each location has certain properties that affect how it can be
used in design
Detail on the charac Leris【ics of the STM and the LTM ls based on Newell and Simon’s model[20 J Extensions have been made to it for visual imagery【1 l,12,13 J and efforts
have been made to codil~~it【21 it must be realized that the contents of the model given here are not folly agreed to in the cognitive psychology community,but the),are cer tainly secure enough to provide a basis for discussing the role of CAD in mechanical design
2.1
Short-term memory Short tern:memorg ls verv fast and powerful The contents of the STM are the information we are aware of,that is,our conscious mind All design operations(。g,visual perception and drawing creation)arebased oninformation in the STM Unfortunately,the STM has limited capacity Studies show that it is limited to approximately seven cognitive units or chunks of information During design, these chunks are visualimages offorn:s,information about fonction,mentaln:odels offit,stepsto represent anideain a CAD system,or other discrete pieces of information Although limited in capacity,the STM is a fast processor with processing times on the order of 100 nls[41
2.2
Long。term memory The long term memory,on the other hand,has essentially infinite capacity,but access is slow Access to LTM is also not direct Memories rntlSt be triggered by some cue or
retrieval strategy based on intbrmation in STM During design,parts of the design are stored in LTM These are relatively easy to cue because,at any time,currently in: portant parts of the design are in the STM and can act as pointers for the knowledge in the LTM
2.3
ExternaI environment
in the experiments run in 1990[291,it was clear that many drawing actions were not used to document the results of the design activity but were part of the design process itselg if the subjects could bare performed these activities in their heads they would have done so without making the sketches,notes,and calculations on paper Thus,it is concluded that the external environment ls often used as an extension of the STM and LTM it ls critical that the media used in this environment support the designer’s cognition Itemizing the match or mismatch between the media and human cognition is one of the objectives of this paper
The approach taken in this paper is to first describe the types ot'information managed(Sect 3)and then discuss the activities performed by the external environment support ing the designer(Sect 4)The types of information and activities are developed in terms of the capabilities of an ideal system Each subsection begins with statements about what the ideal engineering design support system should do Supporting information follows these statements Next, there is a description of how paper and pencil,2 D CAD systems,solid modeling systems,parametric systems,and other support tools meet the ideal Each subsection concludes with 0DD0r【unl Lles for lmprovement
3
Information managed by an ideal mechanical engineering design suppo~system
Mechanical engineers manage a broad range of informa tion in this section,the X arious types of information will be itemized,beginning with the most basic and progress ing to the most demanding
3.1
Form,fit,and fun~ion
The ideal engineering design support system should:
1 Allow designers to work I?om des£red Junction to the other types oj lnlornlation
2 Allow designers to flexibly work on the architecture, shape,^f,and function of parts and(zss0川blies
The mechanical design community has traditionally thought in terms of form,fit,and function Figure 2 shows the interplay among these basic types of information that describe the product being designed Generally,the reason for the obiect being designed is to fulfill some desired functions The form of the parts and assemblies,and the fit between them,depend on the desired function of the product Thus,the ideal system should allow the designer to work ffonl funotion to fornl and fit
The term‘‘form’’actually implies both the architecture and the shape of parts and assemblies(Fig 3)The term ‘a(chǎn)rchitecture’’has come to mean the skeletal structure that maps the function to the form Architecture is the‘‘stick figure”that can be easily manipulated and changed before the shape is refined Shape implies the geometry that adds hodV and detalt to tne arcnltecture utten deslgners i~l-st develop the general architecture of the object being de si~dned then add detaits about shape an(1 fit Where wP n憎today Engineers gener~dly work from the ftnlction of a systel~、to the architecture of an assembly,to the shape of parts iaunction occurs primarily at the con nections or fits between the parts ln an asselnbly ill other wor(1s mnction ls devdopetl ln assemb[ies lhis belng said,CAD systems have primali Ly supported the forln or geometry devetopnlent ot parts
Paper and penci[attm~s easy sketching of architecture with stick fi~ures and their evo[ution to conlponents Paper and pencil atso supports[imited function nlodeling through sketchinl4 actions that show lnotion or flow ln assemblies『9、14]
Both 2 D CA/3 systems and paper and pencil are fimited to simple input of line seglnents to represent the edges of COlnponents Solid naode[ing systelns are stilt Colnponent oriented even though they support the representation of edges,surfl~ces,and sotids Parametric systems gl eafly
lniprove(1 the lllode[illl4 of fornl with the Iimlted ability to modeI nt…d as…blles
Future systel~S need to help the designer visualize fllnction before geometry is fully defined Computer sys tenls are allowing better representation of fllnction,。g, kinelnatic,dynamic,fluid flow,and virtmd reality systems With the continued development 0f COlnputer support tools the ability to work fr0111 fllnction to form will …tlnl_e呲v0Lve
CA/3 systems to date have been part driven Parts are developed and then fittecl to~ether to make an assembly Ihe contributions oftheIayOtlt dlawinK have not beenwe[1 supported Paralnetric systems have begun to l~OVe to a nlore natural flow,but parametric nlode[ing requires the designer to PIan ahead of time the geometric constraint rekltionships that define the part,Mally parametric sys tells refer to the orderlng of the constraints as the design intent Ihis methodo[oD",while lnoving to~ard the ide~d, does not well support the designer as the p[allllillg needed adcls burden and the orderin~nlay not be known initi~flly and lnay change during the deve[oplnent Further,“design intent”as used ill parametric systems is too[imiting(see discusslon of deslfan Intent belowl
OpportunI Extend CAD systems to~d[ow the designer to develop the architecture of parts and assemb[ies to mliltl neede【l mnotion fhey nltlst atlow the designer to work fr0111 the architecture to the shaDe an(1 fit of the conlpo nents themselves lhis wi[1 require workinl4 wlth abstrac tions of parts an(1 asselnbIies as we[1 as buildlng the geometry of objects from their architecture and interfaces with other objects
3.2
Material and manufacturing
The ideal engineering design support system should: 3 Integratetheman@zcturing and assembl),practices and (oltlltl01,1 material usage oy the compan),or its vendors
One of the cornerstones of concurrent engineering is the integration of the development of the product and the processes that support the product Key among these processes are those used to manufacture the parts and assemble them These activities also depend on the selec tion or development of the best materials for the product Thus,as shown in Fig 4,the basic tbrm(architecture and shape),fit,and fonction need to be tied to materials,manufacturing,and assembly
Where we nre todi9,Currently、there are systems that aid in the development of injection molds and sheet metal parts flowever,for most manuthcturing and assembly methods,only text notes have supported this nongeo metric lnformation
OpportuMt),Extend CAD systems to provide the designer with intbrmation about anticipated material and manu
l;acturing methods This needs to be personalized as each
company and vendor has certain materials and manutac
turing and assembly methods that are standard and well
known Knowledge about these should be easily available
to the designer to aid in the development of parts and
assemblies
3.3
Cost
The ideal engineering design support system should:
4 Support the engineer so she or he is ctlv(~re。l the e‰ect
。f each Jblture change 01,1 costⅢit is generated
The cost to make the object being designed is not a part 0f its description,yet it is a major factor in all design considerations It is shown in Fig 5 as closely tied to the material used and the manufacturing method and through these indirectb to the ftinction and fornl Often there is a disconnection during the design process between drawing
what is being designed,but the limitations and targets on it As such,it is critical information As shown in Fig 6,there are requirements on at[the other types of infor mation previously discussed Traditionally,engineers have done a poor]ob at developing requirements tbr products Wher~w。(It6"tod~9,One of the best practices current[}, used to deve[op requirements in industry is quality func tion dep[oyment(QFD)[7,321 Many companies use the results of this method to direct[},feed requirements to the development of components and assemb[ies Admittedly, many of the requirements deve[oped with the QFD are for funotion;however,there are a[ways many constraints on both function and geometry that drive the development of parts and assemb[ies To date,this is not we[1 integrated
with CAD systems
Stauffer【26 J showed that as the design process n~oves from conceptual through[ayout to detail design,the source of constraints moves from those imposed from outside the control of the designer to those based on previous design decisions This imp[ies that not only shou[d requirements like those deve[oped using QFD type methods be integrated,but the reasoning behind earlier decisions also needs to be supported This wit[be further
discussed in the seclion on design intent fSect 3 61
Opportunity CAD systems need to integrate requirements and constraints into the deve[opment of parts and as semblies
3.5
Issues and plans
The ideal engineering design support system should:
6 Support the development,Jbllowing,and updating plans
7 Support the lmtrlagemenl issues not phtnned Jot.
Whereas at[the types of information described so ihr represent the artifacts being designed and the require ments on them,the lot[owing types of information repre sent the process through which the artifacts are developed
The importance of the process has been a concern ln in dustry since the earh 1980s and an area of research since the mid 1980s The tie between product and process is a maior part of concurrent engineering in the late 1990s, this concern became prominent with the development of interest in integrated product and process development (IPPD),the successor to concurrent engineering
Traditionally,the product design community addresses the design process ln terms of the tasks to be completed in dexeloping a new product These tasks are focused on specific design lssues that can be planned tbr in the de velopment of the product However、many issues arise duringthe design ofa productthat can notbe plannedtbr This ls especially true during the development of new
products or during the use of new technologies Figure 7 shows that lSStles and plans address all types of require merits and product information issues or tasks in product design require the designer to develop new lnformation 0ne of the first experiments aimed at unders【anding human Intbrmation processing during design tasks【27 J showed that over two thirds ofthe strategies used by the design engineers during the dexelopment of new products were searches through design space Searches imply that there is a range of potential sohltions to every issue and that the designer must look at several of these ahernative solutions to develop one that ls satisfactory Search strategies are well studied by the artificial intelligence community Three types of strategies defined by computer scientists and identified in the cognitive study were‘‘generate and test”, ‘‘generate and improve”、and‘‘means ends analysis”In each search type,the designer develops and refines the alternatives and compares them to the requirements until son2e satisfactory choice has been made ln the time vailable Based on these findings、in order to support designers,systems must not only track the completion of planned work,but must also support the development
and management of multiple ahernatives for all issues addressed
Where we nre todi9,Project planning and change n2an agement has always been a large part of engineering management Product data management(PDM)systems have made large strides toward integrating the actual de sign work with what was planned These systerns are still maturing
Opportunity Computer support tools need to continue to evoh,e to assist the engineer in developing the product and the process in an integrated fashion
3.6
Intent
The ideal engineering design support system should manage all the previously defined types ofinformat