家用榨汁機(jī)機(jī)電系統(tǒng)設(shè)計(jì)含6張CAD圖
家用榨汁機(jī)機(jī)電系統(tǒng)設(shè)計(jì)含6張CAD圖,家用,榨汁機(jī),機(jī)電,系統(tǒng),設(shè)計(jì),CAD
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XX設(shè)計(jì)(論文)任務(wù)書
Ⅰ、畢業(yè)設(shè)計(jì)(論文)題目:
家用榨汁機(jī)機(jī)電系統(tǒng)設(shè)計(jì)
Ⅱ、畢業(yè)設(shè)計(jì)(論文)工作內(nèi)容:
本課題擬根據(jù)現(xiàn)代榨汁機(jī)產(chǎn)業(yè)對(duì)人們生活的需求,通過(guò)著重設(shè)計(jì)螺旋軸來(lái)設(shè)計(jì)螺桿的特色之處,利用變螺距方式,是的與物料充分?jǐn)D壓,從而開展整體的的結(jié)構(gòu)。具備機(jī)械設(shè)計(jì)、互換性與測(cè)量技術(shù)、AUTO CAD 基本知識(shí)進(jìn)行必要的強(qiáng)度校核、結(jié)構(gòu)設(shè)計(jì)。
技術(shù)要求:
通過(guò)設(shè)計(jì)變螺距螺旋軸來(lái)提高出汁率。
具體工作內(nèi)容:
1) 查閱與課題相關(guān)文獻(xiàn)資料10篇以上,其中英文資料2篇以上,英文資料翻譯5000漢字以上;
2) 設(shè)計(jì)總體設(shè)計(jì)方案,并撰寫課題開題報(bào)告;
3) 對(duì)榨汁機(jī)的各個(gè)零部件進(jìn)行計(jì)算設(shè)計(jì);
4) 設(shè)計(jì)圖紙量:折合成2張A0;
5) 制作設(shè)計(jì)說(shuō)明書一份不少于1萬(wàn)字。
Ⅲ、進(jìn)度安排:
2014年10月20日~2014年11月9日(3周):選擇題目,收集材料,聯(lián)系落實(shí)畢業(yè)實(shí)習(xí)單位,填寫畢業(yè)設(shè)計(jì)任務(wù)書;
2014年11月10日~2014年12月7日(4周):布置任務(wù),明確目標(biāo)、制定計(jì)劃,確定初步畢業(yè)設(shè)計(jì)方案;
2014年12月8日~2015年1月4日(4周):深化初步方案,結(jié)合畢業(yè)實(shí)習(xí)加深對(duì)畢業(yè)設(shè)計(jì)方案的認(rèn)識(shí);
http://www.doc88.com/p-8418036972462.html
2015年1月5日~2015年1月16日(2周):學(xué)生畢業(yè)設(shè)計(jì)方案進(jìn)一步完善;
2015年1月17日~2015年3月1日(6周):繼續(xù)前期工作;
2015年3月2日~2015年5月17日(11周):學(xué)生全部返校,進(jìn)行畢業(yè)設(shè)計(jì)計(jì)算、繪圖,編制畢業(yè)設(shè)計(jì)說(shuō)明書,完成畢業(yè)設(shè)計(jì)工作任務(wù)(2015年3月30日~2015年4月5日接受學(xué)校畢業(yè)設(shè)計(jì)期中檢查);
2015年5月18日~2015年5月31日(2周):畢業(yè)成果預(yù)提交、修改、評(píng)閱、答辯。
Ⅳ、主要參考資料:
【1】陳立德.機(jī)械設(shè)計(jì)基礎(chǔ). 第3版. 北京:高等教育出版社,2007.
【2】《機(jī)械設(shè)計(jì)師手冊(cè)》編寫組.機(jī)械設(shè)計(jì)師手冊(cè). 北京:機(jī)械工業(yè)出版社,1998
【3】吳宗澤,羅圣國(guó)。機(jī)械設(shè)計(jì)課程設(shè)計(jì)手冊(cè). 第2版. 北京:高等教育出版社, 1990
【4】孫恒,陳作模.機(jī)械原理.第7版. 北京:高等教育出版社,1997
【5】吳克堅(jiān),于曉紅,錢瑞明.機(jī)械設(shè)計(jì). 北京:高等教育出版社.1996
【6】李柱. 互換性與測(cè)量技術(shù){M}.北京:機(jī)械工業(yè)出版社,2004
【7】肖振金. 食品工廠機(jī)械與設(shè)備【M】 北京:機(jī)械輕工業(yè)出版社,1991
【8】王三民,諸文俊. 機(jī)械原理與設(shè)計(jì)【M】 北京:中國(guó)輕工業(yè)出版社,2001
【9】催大同,趙素娥,李秋庭. 果蔬加工機(jī)械【M】.北京:中國(guó)農(nóng)業(yè)大學(xué)出版社,1993
【10】成大先.機(jī)械設(shè)計(jì)手冊(cè)【M】. 第5版. 山東:化學(xué)工業(yè)出版社, 2010
【11】仆炎,螺紋連接設(shè)計(jì)與計(jì)算。北京:高等教育出版社,1993
【12】王振華,實(shí)用軸承手冊(cè)。上海:上??茖W(xué)技術(shù)文獻(xiàn)出版社,1989
【13】吳宗澤,機(jī)械結(jié)構(gòu)設(shè)計(jì)。北京:機(jī)械工業(yè)出版社,1987
【14】濮良貴,紀(jì)名剛,機(jī)械設(shè)計(jì)學(xué)習(xí)指南. 第四版.北京:高等教育出版社,2001
【15】周開勤,機(jī)械零件手冊(cè),第四版.北京:高等教育出版社,1980
【16】謝紅, 高鍵. 機(jī)械設(shè)計(jì)[J].現(xiàn)代機(jī)械2002(2):3-5
【17】邱慧君等.機(jī)械原理.北京:高等教育出版社,1999.
【18】廉元國(guó),張永洪. 加工中心設(shè)計(jì)與應(yīng)用[M]. 北京:機(jī)械工業(yè)出版社,1995
【19】成大先主編. 機(jī)械設(shè)計(jì)手冊(cè)(第三版)[M]. 北京:化學(xué)工業(yè)出版社,1993
【20】吳宗澤,羅圣國(guó). 機(jī)械設(shè)計(jì)課程設(shè)計(jì)手冊(cè)(第二版)[M]. 北京:高等教育出版社,1999
【21】吳宗澤.機(jī)械設(shè)計(jì).北京:高等教育出版社,2001
【22】 李勇軍,零件的精度及重復(fù)定位精度設(shè)計(jì)[J].機(jī)械工程師,2012( 5)
【23】S.H.Suh,J.W.Sohn,S.Y.Jung,A closed-loop method for reducing total machining errors: experiment and analysis, Trans. NAMRI/SME15 (1997) 311–316.
【24】J.A. Bosch, Coordinate Measuring Machines and Systems, Marcel Dekker Inc., New York, 1995.
【25】 U. Do rndorf, V.S.B. Kridena, P.M. Ferreira, Optimal Budgeting of Quasi staticMachine Tool Errors, J. Eng. Ind. 116 (1994) 42-53.
指導(dǎo)教師:(簽名: ), 年 月 日
學(xué)生姓名:(簽名: ),專業(yè)年級(jí): 11級(jí)機(jī)械工程
系負(fù)責(zé)人審核意見(從選題是否符合專業(yè)培養(yǎng)目標(biāo)、是否結(jié)合科研或工程實(shí)際、綜合訓(xùn)練程度、內(nèi)容難度及工作量等方面加以審核):
專業(yè)負(fù)責(zé)人簽字: , 年 月 日
附錄一:
選擇榨汁機(jī)的誠(chéng)實(shí)指南
1930年一個(gè)被稱為諾曼·沃克博士的人發(fā)明了一種榨汁機(jī),它首先磨碎和削減生產(chǎn)。由此產(chǎn)生的質(zhì)量被放入一個(gè)亞麻包,放置在液壓機(jī),導(dǎo)演汁淹死一個(gè)壺嘴。(沃克博士活到108歲,他死于沖浪事故)。你仍然可以購(gòu)買這2段“諾沃克”機(jī)約2000美元,這是一個(gè)每個(gè)高昂價(jià)格。和大部分的榨汁機(jī),你會(huì)發(fā)現(xiàn)銷售還沒(méi)有進(jìn)化之后,和大多數(shù)的榨汁機(jī),你會(huì)發(fā)現(xiàn)銷售還沒(méi)有進(jìn)化之后,這讓我們稱之為離心式榨汁機(jī),.離心式榨汁機(jī)工作通過(guò)使用平刀片快速旋轉(zhuǎn)過(guò)濾器的底部。削減生產(chǎn)是扔的過(guò)濾器。由于受離心作用力,果汁然后穿過(guò)小孔通過(guò)過(guò)濾器流出,它的內(nèi)在設(shè)計(jì)包括:
過(guò)濾器很大并且很難清洗干凈。
切割刀片的清洗有一定的危險(xiǎn)性。
過(guò)程包含大量氧化,因此會(huì)有一些垂死和棕色的汁。
有很多令人不愉快感到不舒服的泡沫。
沒(méi)有草藥和芽草之類的所以綠葉蔬菜是不可能的。
這些榨汁機(jī)可以嚴(yán)重的損害你的聽力,不會(huì)受歡迎的,因?yàn)檫B棟房屋或公寓有噪音,沒(méi)有人會(huì)睡好覺(jué)。
最后,設(shè)計(jì)離心式榨汁機(jī),里面是不同于樹木的切削刀。它們轉(zhuǎn)速高達(dá)10000 r/min,旋轉(zhuǎn)產(chǎn)生的摩擦對(duì)職業(yè)是不好的。當(dāng)馬達(dá)早在持續(xù)的抵抗之下10000 r/min,也不是一件容易的事,你可以花費(fèi)在離心式榨汁機(jī)從30美元到100.美元不等,所以你支付什么呢?嗯,事實(shí)上,大多數(shù)品牌和審美設(shè)計(jì).然而最便宜的機(jī)器肯定是周心,不會(huì)最后你長(zhǎng),經(jīng)驗(yàn)和反饋告訴我們,更昂貴的機(jī)器不一定會(huì)長(zhǎng)期工作下去,.事實(shí)上,如果大家都買了榨汁機(jī),并且每天都在使用他們的機(jī)器,我們認(rèn)為幾乎每個(gè)機(jī)器日常使用的市場(chǎng)將被取消,因?yàn)槊刻煊梅▽?shí)際上所有機(jī)器無(wú)法在他們的第一年之內(nèi),讓單獨(dú)在保單之內(nèi)。本指南已經(jīng)寫的幾個(gè)人的累積經(jīng)驗(yàn),跨越4年多。
對(duì)我們來(lái)說(shuō)這是一個(gè)大膽的聲明是榨汁機(jī)是提供保修的。大多數(shù)人我們說(shuō)話,燃盡之前機(jī)器從來(lái)沒(méi)有把它回來(lái)。我們生活在這樣一個(gè)社會(huì)可悲的是,但它制造的大。社會(huì)的另一個(gè)事實(shí)是我們中有多少人新項(xiàng)目的櫥柜,僅次于最可能的新項(xiàng)目的櫥柜,僅次于喬治·福爾曼風(fēng)格烤架。我們相信這是由于上述缺點(diǎn)的這種風(fēng)格的大街離心是迄今為止最購(gòu)買的一種,這榨汁機(jī)處理整個(gè)生產(chǎn)制造過(guò)程,.整個(gè)蘋果,芹菜的整個(gè)頭,性能并不是最好的。一位健康食品作者告訴我們它的偉大在于能夠把一整頭的芹菜榨好,雖然最終,這個(gè)功能是方便,但是這個(gè)過(guò)程仍然破壞果汁,您仍然需要清理每一個(gè)玻璃以后被生產(chǎn)作為過(guò)濾器障礙物更加迅速。
接下來(lái),我們都知道三角皮帶傳動(dòng)的重要性。三角皮帶傳動(dòng)廣泛應(yīng)用于各種各樣的機(jī)器,所以理解和知道如何設(shè)計(jì)很試驗(yàn)臺(tái)上三角皮帶激勵(lì)等三角皮帶和滑輪是兩個(gè)最重要的部分三角皮帶驅(qū)動(dòng),中心距,滑輪的直徑和滑輪直徑是最基本的參數(shù)三角皮帶傳動(dòng)三角皮帶驅(qū)動(dòng)。驅(qū)動(dòng)皮帶輪和動(dòng)力輸出輪,我們?cè)O(shè)計(jì)的直徑比速度的基礎(chǔ)。
三角皮帶傳動(dòng)驅(qū)動(dòng)皮帶輪和動(dòng)力輸出皮帶輪和無(wú)休止的三角皮帶繞著兩個(gè)滑輪。這個(gè)三角皮帶驅(qū)動(dòng)器配有扭矩測(cè)量裝置在rpm傳感器分配給驅(qū)動(dòng)皮帶輪和動(dòng)力輸出皮帶輪,不斷檢測(cè)輪,兩個(gè)傳感器與電子控制哪些,決定之間的傳動(dòng)比傳動(dòng)和動(dòng)力輸出裝置檢測(cè)到滑輪,校準(zhǔn)設(shè)備,這將一組齒輪速比與定義扭矩與電子控制,和電子控制與電子評(píng)估者。
本發(fā)明涉及提供一個(gè)三角皮帶驅(qū)動(dòng),可以確定現(xiàn)有扭矩在不同驅(qū)動(dòng)同一負(fù)載通過(guò)簡(jiǎn)單的手段和最優(yōu)轉(zhuǎn)矩現(xiàn)有在不同驅(qū)動(dòng)同一負(fù)載以最優(yōu)的方式,通過(guò)簡(jiǎn)單的手段和作為的運(yùn)行部分的函數(shù),v帶傳動(dòng),驅(qū)動(dòng)輪,動(dòng)力輸出裝置和三角皮帶,控制并調(diào)整它。
三角皮帶驅(qū)動(dòng)按照發(fā)明配有扭矩測(cè)量裝置,采用三角皮帶在v形帶溝槽的深度滲透的動(dòng)力和動(dòng)力輸出裝置滑輪,因此,通常被認(rèn)為是滑移和沒(méi)有考慮在內(nèi),從而造成的可變傳動(dòng)比以及這個(gè)齒輪比率相比,這些不斷變化的函數(shù)驅(qū)動(dòng)皮帶輪上的負(fù)載,與預(yù)定的力矩電子設(shè)備,評(píng)估這對(duì)扭矩的變化差異獲得的方式,導(dǎo)致實(shí)際轉(zhuǎn)矩分別。
通過(guò)這可以在一個(gè)簡(jiǎn)單的和確定的方式和調(diào)整扭矩;同時(shí)檢測(cè)并立即解決發(fā)展中問(wèn)題,過(guò)載,磨損等的各種機(jī)器和設(shè)備驅(qū)動(dòng),如農(nóng)業(yè)機(jī)械、工業(yè)機(jī)械和l相似,.不同的旋轉(zhuǎn)直徑帶是由這些不同的滲透深度的三角皮帶,正因?yàn)槿绱?兩個(gè)滑輪.T或齒輪的不同轉(zhuǎn)速比的兩個(gè)滑輪是通過(guò)改變這措施.為了彌補(bǔ)這一行動(dòng),或改變傳動(dòng)比通過(guò)傳感器,根據(jù)負(fù)載驅(qū)動(dòng)皮帶輪和他穿透深度的滑輪V帶輪,滑輪不斷發(fā)現(xiàn)通過(guò)滑輪的v帶.不斷發(fā)現(xiàn)通過(guò)傳感器,和這些數(shù)據(jù)集中到電子設(shè)備.由此形成一個(gè)傳動(dòng)比。
空載條件或知道他三角皮帶驅(qū)動(dòng)負(fù)載校準(zhǔn)標(biāo)定裝置的執(zhí)行將RPM或傳動(dòng)比分配給其他一組上,述描述的具體化將因此完全揭示發(fā)明的一般性質(zhì),其他人可以通過(guò)運(yùn)用現(xiàn)有知識(shí),容易修改和/或調(diào)整等各種應(yīng)用程序并且沒(méi)有離開通用概念和它的具體體現(xiàn),因此,適應(yīng)和修改等,目的是應(yīng)該理解的意義和范圍內(nèi)對(duì)應(yīng)披露的化身,是理解詞組或術(shù)語(yǔ)使用本是為目的的描述,而不是限制。
理解上述理論的目的是設(shè)計(jì)v形帶激勵(lì)等總體設(shè)計(jì)要求是得到最好的兩個(gè)滑輪之間的中心距離. .當(dāng)然,設(shè)計(jì)師有幾個(gè)知道條件他/她開始設(shè)計(jì)之前,如驅(qū)動(dòng)輪的轉(zhuǎn)速、傳動(dòng)皮帶輪之間的傳動(dòng)比和動(dòng)力機(jī)械故障輪(或動(dòng)力輸出輪),電力傳輸和三角皮帶的工作環(huán)境激勵(lì)等設(shè)計(jì)的最終目的是使三角皮帶傳動(dòng)的最小規(guī)模的會(huì)議,所有的工作需求的基礎(chǔ)。
眾所周知,三角皮帶是最重要的三角皮帶傳動(dòng)的一部分。然而重要理解三角皮帶的設(shè)計(jì)和選擇,人造絲和橡膠v形帶廣泛用于電力的傳動(dòng).v帶是有兩個(gè)系列:標(biāo)準(zhǔn)三角皮帶和高容量三角皮帶,皮帶可以使用較短的中心距離。三角皮帶的優(yōu)點(diǎn)之一是成本低,和輸出功率高,可能增加了操作幾個(gè)v帶,身邊的皮帶驅(qū)動(dòng)應(yīng)該以同樣的速度伸展為了保持負(fù)載同樣分給them.When皮帶斷裂,通常必須被替代。開車可能傾向前或在任何角度的一邊的下邊.另外的優(yōu)勢(shì)是,它包括皮帶槽角,通常從34-38的帶槽的廣泛作用,使機(jī)器大量增加牽引力并且由傳送帶傳遞。
而另一個(gè)重要部分三角皮帶驅(qū)動(dòng)輪,它可能用廣泛應(yīng)用在是鑄鐵、鋼板或模鑄金屬灰色鑄鐵這些材料,當(dāng)三角皮帶的速度不超過(guò)25米/秒,我們應(yīng)該采用HT150滑輪的材料,當(dāng)速度是25到45米/秒之間,然后我們可以采用球墨鑄鐵,鑄鋼、鍛鋼,我們也可以焊接穿孔鋼板作為滑輪,當(dāng)需要的力不是很大時(shí),滑輪也可以用鑄鋁或其他材料制作.皮帶輪由輪緣,網(wǎng)絡(luò)和輪中心構(gòu)成.滑輪是一個(gè)市場(chǎng),允許調(diào)整螺桿的寬度的有效直徑滑輪是不同的,和溫和的變化速度比通常有關(guān),小皮帶輪傳動(dòng)皮帶輪,和大用作動(dòng)力輸出裝置滑輪。
在我們理解常用的v型皮帶傳動(dòng)的結(jié)構(gòu),我們應(yīng)該分析三角皮帶的力量,三角皮帶的分析更重要,主力拉力和壓力,和壓力包括拉伸應(yīng)力、彎曲應(yīng)力和離心壓力設(shè)計(jì)必須使拉力和壓力不超過(guò)固定值以避免滑動(dòng),我們也應(yīng)該使發(fā)射功率,三角皮帶的張力和速度必須滿足這一條件,三角皮帶有足夠的抗疲勞強(qiáng)度和一個(gè)明確的允許值。
接下來(lái),我們應(yīng)該知道軸、聯(lián)軸器和滾動(dòng)接觸軸承。
幾乎所有機(jī)器包含軸軸最常見的形狀是圓形截面可以是實(shí)心或空心(空心軸可能導(dǎo)致重量?jī)?chǔ)蓄).通常軸有時(shí)被用作在螺絲刀葉片,套筒扳手和控制旋鈕莖。
軸必須有足夠的抗扭強(qiáng)度傳輸扭矩和壓力過(guò)大。它也足夠扭力tiff,安裝組件不偏離足夠硬,一個(gè)安裝組件不過(guò)分偏離原來(lái)的角位置相對(duì)于第二個(gè)組件安裝在同一個(gè)軸上總體而言,扭轉(zhuǎn)角度軸的長(zhǎng)度不應(yīng)超過(guò)或者等于20mm。
軸安裝本質(zhì)通過(guò)齒輪等設(shè)備和傳輸功率,滑動(dòng),凸輪和離合器這些設(shè)備介紹部隊(duì)試圖彎軸;因此,軸必須足夠嚴(yán)格,防止超載的發(fā)生.在設(shè)備內(nèi)部,軸的彎曲撓度之間的長(zhǎng)度不應(yīng)超過(guò)0.01英寸.滿足軸承支持。
此外,軸必須能夠承受彎曲和扭矩的組合作用,所以,必須考慮扭轉(zhuǎn)和彎矩的當(dāng)量載荷.,因?yàn)榕ぞ睾蛷澗貢?huì)產(chǎn)生變應(yīng)力,在許用應(yīng)力中也應(yīng)該有一個(gè)考慮疲勞現(xiàn)象的安全系數(shù)。
通常軸直徑小于3英寸,材料可采用含碳量約為0.4%的冷軋鋼,直徑在3至5英寸大的,則采用鍛造毛坯,。當(dāng)直徑大于5英寸時(shí),則采用鍛造毛坯,然后機(jī)械加工到所要求的尺寸。輕載時(shí),廣泛采用塑料軸。由于塑料是電的不是導(dǎo)體,在電器中用它做軸比較安全。
齒輪和皮帶輪等零件通過(guò)鍵連接在軸上。在對(duì)鍵及軸上與之相應(yīng)的鍵槽進(jìn)行設(shè)計(jì)時(shí),必須進(jìn)行認(rèn)真的計(jì)算。例如,應(yīng)力集中發(fā)生在軸鍵槽,由于鍵槽存在使軸的橫截面面積間隙,會(huì)料被進(jìn)一步削弱了軸的強(qiáng)度。
如果軸以速度轉(zhuǎn)動(dòng),,將會(huì)發(fā)生強(qiáng)烈的振動(dòng),可能會(huì)毀壞整臺(tái)機(jī)器。,知道這些臨界速度的大小是很重要的,這樣就可以避免它的發(fā)生,一般憑經(jīng)驗(yàn)來(lái)說(shuō),工作速度和臨界轉(zhuǎn)速之間的應(yīng)該至少相差20%。
軸設(shè)計(jì)的另一個(gè)重要方面是軸與軸之間的直接聯(lián)接方法,這是有剛性或者彈性聯(lián)軸器來(lái)實(shí)現(xiàn)的。
聯(lián)軸器是用來(lái)把兩相鄰的軸端聯(lián)接起來(lái)的裝置,在機(jī)械結(jié)構(gòu)中,聯(lián)軸器被用來(lái)實(shí)現(xiàn)兩根轉(zhuǎn)軸之間的半永久聯(lián)接。在機(jī)器的正常的使用期間內(nèi),這種聯(lián)軸器一般不必拆開,在這種意義上,可以說(shuō)聯(lián)軸器的聯(lián)接是永久性的。但在緊急情況下,或者需要更換已經(jīng)磨損的零件時(shí),可以先把聯(lián)軸器拆開,然后再連接上。
有幾種類型的軸聯(lián)軸器,其特征取決于它們的用途,如果制造工廠或船舶螺旋槳需要一根特別長(zhǎng)的軸,可以采用分段的方式將其制造出來(lái),然后采用剛性聯(lián)軸器將各段聯(lián)接起來(lái)。一種常用的聯(lián)軸器是由兩個(gè)配對(duì)的法蘭組成,這兩個(gè)法蘭盤借助靠鍵傳動(dòng)的軸套聯(lián)接到相鄰兩節(jié)軸的兩端,然后用螺栓穿過(guò)法蘭聯(lián)接起來(lái)形成剛性接頭。相互聯(lián)接的兩根軸通常是靠法蘭面的槽口來(lái)對(duì)準(zhǔn)的,
在把屬于不同的設(shè)備(例如一個(gè)電動(dòng)機(jī)和一個(gè)變速箱)的聯(lián)聯(lián)接起來(lái)的時(shí)候,要把這些軸精確地對(duì)準(zhǔn)是比較困難的,此時(shí)可以采用彈性聯(lián)軸器。這種聯(lián)軸器聯(lián)接的方式可以吧由于被聯(lián)接的軸線不重合所造成的有害影響減少到最低程度。彈性聯(lián)軸器也允許被聯(lián)接的軸在它們各自的載荷系統(tǒng)作用下產(chǎn)生偏斜或者在軸線方向自由移動(dòng)而不至于相互干擾。彈性聯(lián)軸器也可以用來(lái)減輕一根軸傳動(dòng)另一根軸上的沖擊載荷和振動(dòng)的強(qiáng)度。
幾乎所有軸都裝有滾動(dòng)軸承。對(duì)于球軸承和滾子軸承,一個(gè)機(jī)器設(shè)計(jì)員應(yīng)該考慮下面五個(gè)方面::(a)壽命與負(fù)載的關(guān)系;(b)剛度、也就是在荷載下的變形量;(c)摩擦:(d)磨損;(e)噪音。對(duì)于中等負(fù)載和轉(zhuǎn)速選擇一個(gè)標(biāo)準(zhǔn)的軸承,通常都可以抱著其令人滿意的工作性能。當(dāng)載荷較大時(shí),軸承變得重要起來(lái)。在轉(zhuǎn)速高的場(chǎng)合需要有專門的冷卻裝置,而這啃會(huì)增加摩擦阻力。磨損主要由于污染物的進(jìn)入引起的,必須選用密封裝置以防止周圍環(huán)境的不良影響。
因?yàn)榇笈可a(chǎn)這種方式?jīng)Q定了球軸承和滾子軸承不但質(zhì)量高,而且價(jià)格低,因而機(jī)器設(shè)計(jì)人員的任務(wù)是選擇而不是設(shè)計(jì)軸承。滾動(dòng)接觸軸承通常是采用硬度大約900HV、整體淬火的剛來(lái)制造的。但在許多機(jī)構(gòu)上不使用專門的套圈,而將相互作用的表面淬硬到大約600HV。滾動(dòng)軸承由于在工作中會(huì)產(chǎn)生高的應(yīng)力,其主要失效形式是金屬疲勞,這一點(diǎn)并不奇怪,目前正在進(jìn)行大量的工作以求改進(jìn)這種軸承的可靠性。通常設(shè)計(jì)軸承中將會(huì)有90%的軸承具有超過(guò)一百萬(wàn)轉(zhuǎn)的壽命。
不承受責(zé)任的事實(shí)基本設(shè)計(jì)球和滾子軸承的軸承制造商,機(jī)器設(shè)計(jì)者必須從正確的升值的義務(wù)由軸承,不僅要考慮軸承選擇而且還要考慮軸承的正確安裝條件。軸承的配合比賽在軸或到住房是至關(guān)重要的,因?yàn)樗麄兊慕Y(jié)合影響軸承的內(nèi)部間隙以及保存所需的干擾程度可以引起嚴(yán)重的麻煩擔(dān)憂,經(jīng)常位于軸向內(nèi)部競(jìng)賽對(duì)接肩膀。此時(shí),半徑是重要為避免應(yīng)力集中和球比賽提供了提供了一個(gè)半徑或倒角允許空間。
設(shè)計(jì)生活不是決定性的因素,通常以確定最大載荷下軸承將轉(zhuǎn)移的數(shù)量意味著可以應(yīng)用于軸承的負(fù)荷,這是固定的或輕微的旋轉(zhuǎn)運(yùn)動(dòng),而不會(huì)影響它的運(yùn)行品質(zhì)隨后轉(zhuǎn)動(dòng)motion.This已經(jīng)由實(shí)踐經(jīng)驗(yàn)時(shí)的負(fù)載應(yīng)用到軸承導(dǎo)致的總變形滾動(dòng)體和滾道接觸在任何時(shí)候不超過(guò)0.01%的滾動(dòng)體直徑.這相當(dāng)于直徑25mm的求產(chǎn)生0.0025mm的永久變形。
只有將軸承與周圍環(huán)境適當(dāng)?shù)母糸_,許多軸才能成功的實(shí)現(xiàn)它們的作用,在某些情況下,必須保護(hù)環(huán)境,使其不受潤(rùn)滑劑和軸承便面磨損生產(chǎn)物的污染,軸承設(shè)計(jì)的一個(gè)重要組成部分是使密封裝置起到應(yīng)有作用。此外,對(duì)摩擦學(xué)研究員來(lái)說(shuō),為了任何目的而應(yīng)用于運(yùn)動(dòng)零部件上的密封裝置都是他們感興趣的。因?yàn)槊芊庋b置是軸承系統(tǒng)部分,只有根據(jù)適當(dāng)軸承理論才能設(shè)計(jì)出令人滿意的封密裝置。雖然它們很重要,與軸承其他方面的研究工作相比,到目前為止在密封裝置的研究方面所作出的工作相比,到目前為止在密封裝置的研究方面所做出的工作還是比較少的。
在最后,我們將介紹減速器。
減速器是一個(gè)動(dòng)態(tài)的交流機(jī)構(gòu),利用齒輪的速度轉(zhuǎn)換器,減速電機(jī)轉(zhuǎn)速的旋轉(zhuǎn)數(shù),和有更大的扭矩機(jī)構(gòu).減速器的作用:
(1) 同一時(shí)間,速度提高輸出扭矩,輸出轉(zhuǎn)矩比由減速電機(jī)輸出,但要注意超過(guò)額減速的同時(shí)降低了負(fù)載的慣量,慣量的減少為減速比的平方。大家可以看一下一般的電機(jī)都有一個(gè)慣量數(shù)值。
(2) 定扭矩減速器。
通用斜齒輪減速器減速機(jī)(包括平行軸斜齒輪減速機(jī),蝸輪減速機(jī)、斜齒輪減速機(jī)等。)行星齒輪減速機(jī)、擺線減速機(jī)、蝸輪減速機(jī)、行星摩擦無(wú)級(jí)變速機(jī)械機(jī)器。
第一,國(guó)內(nèi)許多由齒輪傳動(dòng)減速器,蝸桿傳動(dòng)為主,但功率和負(fù)載比通常很小,或者速度比大而機(jī)械效率過(guò)低的問(wèn)題,另外,材料的質(zhì)量和技術(shù)水平也有很多弱點(diǎn),大規(guī)模的減速齒輪的問(wèn)題特別突出,壽命不是很長(zhǎng),國(guó)內(nèi)使用大型減速齒輪(約50 kw),許多從國(guó)外(例如區(qū)別,德國(guó)等等)進(jìn)口的60年代開始幾齒減速機(jī)等等,不同傳播,擺線銷齒輪傳動(dòng),泛音傳輸生產(chǎn)具有傳動(dòng)比大,體積小,機(jī)械效率高等優(yōu)點(diǎn)。但它傳播理論限制,不能傳輸過(guò)大的功率,功率一般都必須小于40千瓦,因?yàn)樵趥鞑ダ碚撋?技術(shù)水平和材料質(zhì)量方面沒(méi)有突破,因此,還不能從根本上解決傳動(dòng)功率大,傳動(dòng)比大,,體積小,重量輕,,機(jī)械效率高等這些要求。90年代的初期,國(guó)內(nèi)出現(xiàn)三環(huán)(齒輪)的減速器,是一種齒輪傳動(dòng)減速裝置,可以實(shí)現(xiàn)大傳動(dòng)比,傳動(dòng)負(fù)載能力也比較大。它體積和重量都是輕于定軸齒輪減速器,結(jié)構(gòu)簡(jiǎn)單,效率也高因?yàn)檫@個(gè)減速齒輪三軸平行結(jié)構(gòu)簡(jiǎn)單,因此造成功率/體積比仍很小,其輸入軸和輸出軸不在同一軸線上,這個(gè)在使用上沒(méi)有許多不便,北京理工大學(xué)研制成功的內(nèi)平動(dòng)齒輪減速器,不僅具有三環(huán)減速器的優(yōu)點(diǎn),還有著大的功率/重量比值,以及輸入軸和輸出軸在同一軸線上的優(yōu)點(diǎn),處于國(guó)內(nèi)領(lǐng)先地位,國(guó)內(nèi)有少數(shù)高等學(xué)校和廠礦企業(yè)對(duì)齒輪傳動(dòng)中的某些原理做些研究工作,發(fā)表過(guò)一些研究論文,在利用擺線齒輪作平動(dòng)減速器開展了一些工作。
(2) 穩(wěn)定運(yùn)動(dòng)減速器齒輪的工作原理簡(jiǎn)介、穩(wěn)定運(yùn)動(dòng)齒輪減速機(jī)是指在一對(duì)齒輪減速器傳動(dòng)中,齒輪在平動(dòng)發(fā)生器的驅(qū)動(dòng)下作平面平行運(yùn)動(dòng),通過(guò)齒廓間的嚙合,驅(qū)動(dòng)另一個(gè)齒輪作定,通過(guò)之間的齒廓嚙合,啟動(dòng)另一個(gè)牙齒輪作定軸減速轉(zhuǎn)動(dòng),實(shí)現(xiàn)減速傳動(dòng)的作用。平動(dòng)發(fā)生器可采用平行四邊形機(jī)構(gòu),或者正旋機(jī)構(gòu)或十字滑塊機(jī)構(gòu)。平動(dòng)發(fā)生器可以是虛擬的采用平行四邊形機(jī)構(gòu),也可以采用實(shí)體的平行四邊形機(jī)構(gòu)。有實(shí)用價(jià)值的平動(dòng)齒輪機(jī)構(gòu)為嚙合齒輪機(jī)構(gòu),因此又可分為內(nèi)齒輪并做減速轉(zhuǎn)動(dòng)輸出。該機(jī)構(gòu)也稱三環(huán)減速器。由于內(nèi)齒輪傳動(dòng),兩曲柄中心能設(shè)置在外齒輪的齒圈內(nèi)部,大大減少了機(jī)構(gòu)整體尺寸。由于外齒輪作平動(dòng),兩曲柄中心能設(shè)置在外齒輪的齒圈內(nèi)部,大大減少了機(jī)構(gòu)整體尺寸。由于內(nèi)齒輪機(jī)構(gòu)傳動(dòng)效率高、體積小、輸入輸出同軸線,故有廣泛的應(yīng)用前景。
(3) 該項(xiàng)目技術(shù)特點(diǎn)和關(guān)鍵性功能的新的穩(wěn)定的“動(dòng)作”減速機(jī)齒輪和國(guó)內(nèi)外有減速機(jī)齒輪相比,具有以下特點(diǎn):(1)傳動(dòng)比范圍大,自I= 10,起可能達(dá)到最達(dá)的幾千I,若制造大速傳動(dòng)比的減速器,則顯示了這種齒輪減速器的優(yōu)點(diǎn)。(2)傳動(dòng)功率范圍大,并可與電動(dòng)機(jī)連接一體制造。(3)結(jié)構(gòu)簡(jiǎn)單,體積小,重量是輕,比,現(xiàn)有的機(jī)齒輪減速器減少1/3左右。(4)機(jī)械效率很高。(5)此減速器輸入軸和輸出軸在同一的軸線上。因缺少數(shù)據(jù),表中所列的各減速器的功率/重量比是最優(yōu)越的。
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【3J】.K.索爾茲伯里,J.J.克雷格的手:力控制和運(yùn)動(dòng)學(xué)問(wèn)題“Int。1。機(jī)械設(shè)計(jì)技術(shù)研究1、第一4-17(1982)。
【4】Dubey r和J.Y.S. Luh,“機(jī)械設(shè)備控制與自動(dòng)化,羅利(1987年3月),頁(yè)1066 - 1072。
【5】、7W.K. K.W. Jeong、鐘、y . Youm》“發(fā)展POSTECH 7自由度直接驅(qū)動(dòng)設(shè)計(jì)”3日ISRAM Conf . .溫哥華(7月。1990)頁(yè)577 - 582。
附錄二:
The Honest Guide to Choosing a Juicer
In the 1930’s a cap called Dr Norman Walker invented a juicer which firstly grated and cut produce . The resulting mass was then to be put into a linen bag and placed under a hydraulic press, directing juice drown a spout.(Dr Walker lived to 108 years of age, he died in a surfing accident). You can still purchase this 2-stage “Norwalk” machine for around $2000, which is a every prohibitive price indeed. And most of the juicer you will find on sale haven’t evolved much since then,And most of the juicer you will find on sale haven’t evolved much since then,which brings us to called it Centrifugal juicers.Centrifual juicers work by using a flat cutting blade on the bottom of a rapidly spinning strainer. Cut produce is flung out over the sides of the strainer . Due to the cantrifugal force, juice then passes through tiny holes in the strainer.Features intrinsic this design include:
f the two pulleys.The RPM or gear ratio of the two pulleys is changed by means of this action.To compensate for this action,the RPM or gear ratio is changed by means of the rpm sensor,depending on the load on the drive pulley and he penetration depth into pulleys of the v-belt.The rpm of The strainers are huge and a pain to clean .
The cutting blades are tricky to clean and some are particularly dangerous to handle.
The process incorporate mass oxidization and therefore a dying and brown juice.
There is a lot of unpleasant forth .
Leafy green vegetables are impossible,so no herb and no wheatgrass pulp in the juice.
These juicers can seriously damage your hearing, and won’t be popular in a terraced house or flat, or if anyone is still in bed.
Ultimately, the technology inside a centrifugal juicer is not unlike that of a tree cutter. They’re spinning at up to 10000rpm.The resulting frictional heat is not good. for your juice.Neither is 10000rpm an easy task for a motor when under constant resistance,The amount you can spend on centrifugal juicer varies from$30 to over $100.so what are you paying for?Well ,in truth, mostly brand name and aesthetic design.While the cheapest of machines are certainly week hearted and not going to last you long ,experience and feedback tells us that more expensive machines don’t necessary last any longer.In fact ,if everyone who bought a juicer used their machine every day we think nearly every machine on the market would be withdrawn because with daily usage virtually all machines would fail within their year,let alone within warranty. This guide has been written as a result of the cumulative experience of several of several people,spanning over 4 years and many juices.
And that’s a brave statement for us to make but far braver is the warranty provided with juicer. Most people we speak to that have burnt out previous machines never even took it back. We live in a throw away society sadly, but it’s great for manufactures . Another fact of society is how many of us new item to be left in the cupboard , second only to the most likely new item to be left in the cupboard, second only to the George Foreman style grills. We believe this is because of the above drawbacks of this style of juicer-as the high street centrifugal is by far the most purchased type of this juicer-as the high street centrifugal is by far the most purchased type of juicer in the UK.Centrifugal juicers that handle whole produce.What a feature,hole apples,whole heads of celery.Having said that,impatience isn’t the highest virtue.One health food author tells us “It’s great being able able to put in a whole head of celery, but the keeps burning out and I have to take it to the shop”.Ultimately, this feature is one of convenience,but the process still destroys the juice,and you still have to clean up after every glass produced as the strainer clog seven more rapidly.
Next ,we all know the importance of the V-belt Drive. The v-belt drive are widely used in all kinds of machines,so to understand and know how to design it is very necessary.The v-belt drive.The v-belt and the pulley are two most important parts of v-belt drive,the center distance,the diameter of the pulleys and the rpm of the pulleys are the most essential parameters of the v-belt drive. The v-belt drive has a drive pulley and a power take-off pulley,we design their diameters in the basis of speed ratio.
The v-belt drive has a drive pulley and a power take-off pulley and endless v-belt rotating around both pulleys. This v-belt drive is equipped with a torque measuring device in that an rpm sensor is assigned to both the drive pulley and the power take-off pulley,which continuously detects the pulley rpm,the two rpm sensor are connected with an electronic control which determines the gear ratio between the drive and the power take-off pulleys from the detected rpm,a calibration device,which associates a set gear ratio with a define torque is connected with the electronic control, and the electronic control is connect with an electronic evaluator.
The invention relates to the provision of a v-belt drive,where it is possible to determine the torque existing at different drive loads by simple means and in an optimal the torque existing at different drive loads by simple means and in an optimal manner,as a function of the coorperating parts of the v -belt drive,drive pulley, power take-off and v-belt,and to control and adjust it in his way.
The v-belt drive in accordance with the invention is equipped with a torque measuring device , which uses the depth of penetration of v-belt in the v-belt grooves of the drive and power take-off pulleys ,which beretofore often had been considered to be slippage and had not been taken into account,as well as the variable gear ratio caused thereby and compares this gear ratio,which continuously changes as a function of the load on the drive pulley,in an electronic device with a predetermined torque, evaluates this differences obtained in manner for the changing torques,which results in the respectively actual torque.
By means of this it is possible in a simple and assured manner and adjust the torque;at the same time detect and immediately remedy developing troubles,overloads,wear and the like in connection with the various machines and devices to be powered,such as agricultural machinery,industrial machinery and the like.Differing rotational diameter of the belt are caused by these differing penetration depths of the v-belt and,because of that ,different rpm oboth pulleys is continuously detected by means of the v-belt.The rpm of both pulleys is continuously detected by means of the rpm sensors,and these numbers are centered into the electronic device.which forms a RPM gear ratio therefrom.
In the no-load condition or with a know load of he v-belt drive a calibration is performed in the calibration device by assigning the RPM or gear ratio to a set torque.The foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can , by applying current knowledge,readily modify and /or adapt for various applications such specific embodiments without departing from the generic concept,and ,therefore,such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments .It is to be understood that phraseology or terminology employed herein is for the purpose of description and not limitation.
The purpose of understanding the above theory is to design the v-belt drive.The total design requirement is to get the best distance between the centres of the two pulleys.. Of course,the designer has a few know conditions before he/she start the design, such as the rpm of the drive pulley,the gear ratio between the drive pulley and the power take -off pulley(or the rpm of the power take-off the pulley),the power to be transmitted and the work circumstances of the v-belt drive.The final purpose of the design is to make the v-belt drive have the least size in the basis of meeting to all the work requirements.
As known to all ,the v-belt is the of the most important part of the v-belt drive. Scompreis important to comprehend the construction of the v-belt and to choose it .the rayon and rubber v-belt are widely used for power transmission.Such belts are made in two series:the standard v-belt are and the high capacity v-belt .The belt can be used with short center distances and are made endless. One of the virtues of the v-belt is that the cost low,and power output may be increased by operating several belts side by side.All the belts in the drive should stretch at the same rate in order to keep the load equally divided among them.When one of the belt breaks, the group must usually be replaced. The drive may be inclind at any angle with tight side either top or bottom.Another advantage is that the include angle for the belt groove is usually from 34-38,the widing action of the belt in the groove gives a large increase in the tractive force developed by the belt.
Another important part of the v-belt drive is the pulley,it may be made of cast iron,sheet steel or die cast metal ,gray cast-iron is widely used of all these materials.When the speed of the v-belt is not more than 25m/s,we should adopt HT150 as the materials of the pulleys;When the speed is between 25 to 45m/s,then we can employ nodular cast iron,cast steel or forged steel,we also can weld the punched steel plate to use as the pulleys.When the power delivered is not very much ,the pulleys also can be made in cast aluminum or plastic.The pulley is composed by wheel flange,web and wheel nave.Pulley are an the market that permit an adjustment in the width of the groove.The effective diameter of the pulley is varied,and the moderate changes in the speed ratio can be secured.Usually, the small pulley is the drive pulley ,and the large one is used as the power take-off pulley.
After we understand the usual structure of the v belt drive ,we should analyse the force of the v-belt,the analysis of the v-belt is more important,the main force are pulling force and stress,and the stress include pulling stress,bending stress and centrifugal stress.The designer must make the pulling force and the stress are not more than the permanent value.In order to avoid the slip slide,we also should make the transmitted power,the pulling force and the speed of v-belt must be satisfied ,it is to say.the v-belt has enough fatigue resistance and a definite lifetime.
Next,we should know the shafts、couplings and rolling contact bearings.
Virtually all machines contain shafts.The most common shape for shafts is circular and the cross section can be either solid or hollow(hollow shafts can result in weight savings).Rectangular shafts are sometimes used as in screwdriver blades,socket wrenches and control knob stems.
A shafts must have adequate torsional strength to transmit torque and not be overstressed. It also be torsionally tiff enough so that one mounted component does not deviate stiff enough so that one mounted component doesn’t deviate excessively from its original angular position relative to a second component mounted on the same shaft.Generally speaking,the angle of twist should not exceed one degree in a shaft length equal to 20 diameters.
Shafts are mounted inbearings and transmit power through such devices as gears,pullerys,cams and clutches.These devices introduce forces which attempt to bend the shaft;hence,the shafts must be rigid enough to prevent overloading of the supporting bearings.In general,the bending deflection of a shaft should not exceed 0.01 in .perft to length between bearing supports.
In addition,the shafts must be able to sustain a combination of bending and torsional loads.Thus an equivalent load must be considered which takes into account both torsion and bending.Also, the allowable stress must contain a factor of safety which includes fatigue,sine torsional and bending stress reversal occur.
For diameters less than 3 in the usual shaft material is cold-rolled ateel containing about 0.4percent carbon.Shafts are either cold-rolled or forged in sizes from 3 in . To 5 in,shafts are forged and machined to size.Plastic shafts are widely used for light load applications.One advantage of using plastic is safety in electrical applications,since plastic is a poor conductor of electricity.
Component such as gear and pullerys are mounted on shafts by means of key.The design of the key and corresponding key way in the shaft must be quickly evaluated. For example,stress concentrations occur in shafts due to keyways ,and the material removed to from the keyway further weakens the shaft.
If shafts are run at cirtical speed
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