家用榨汁機機電系統(tǒng)設計含6張CAD圖
家用榨汁機機電系統(tǒng)設計含6張CAD圖,家用,榨汁機,機電,系統(tǒng),設計,CAD
附錄一：
選擇榨汁機的誠實指南
1930年一個被稱為諾曼·沃克博士的人發(fā)明了一種榨汁機，它首先磨碎和削減生產(chǎn)。由此產(chǎn)生的質(zhì)量被放入一個亞麻包,放置在液壓機,導演汁淹死一個壺嘴。(沃克博士活到108歲,他死于沖浪事故)。你仍然可以購買這2段“諾沃克”機約2000美元,這是一個每個高昂價格。和大部分的榨汁機,你會發(fā)現(xiàn)銷售還沒有進化之后,和大多數(shù)的榨汁機,你會發(fā)現(xiàn)銷售還沒有進化之后,這讓我們稱之為離心式榨汁機，.離心式榨汁機工作通過使用平刀片快速旋轉(zhuǎn)過濾器的底部。削減生產(chǎn)是扔的過濾器。由于受離心作用力，果汁然后穿過小孔通過過濾器流出，它的內(nèi)在設計包括:
過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性。
過程包含大量氧化,因此會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。
這些榨汁機可以嚴重的損害你的聽力,不會受歡迎的，因為連棟房屋或公寓有噪音,沒有人會睡好覺。
最后,設計離心式榨汁機，里面是不同于樹木的切削刀。它們轉(zhuǎn)速高達10000 r/min,旋轉(zhuǎn)產(chǎn)生的摩擦對職業(yè)是不好的。當馬達早在持續(xù)的抵抗之下10000 r/min,也不是一件容易的事，你可以花費在離心式榨汁機從30美元到100.美元不等,所以你支付什么呢?嗯,事實上,大多數(shù)品牌和審美設計.然而最便宜的機器肯定是周心,不會最后你長,經(jīng)驗和反饋告訴我們,更昂貴的機器不一定會長期工作下去，.事實上,如果大家都買了榨汁機，并且每天都在使用他們的機器，我們認為幾乎每個機器日常使用的市場將被取消,因為每天用法實際上所有機器無法在他們的第一年之內(nèi)，讓單獨在保單之內(nèi)。本指南已經(jīng)寫的幾個人的累積經(jīng)驗,跨越4年多。
對我們來說這是一個大膽的聲明是榨汁機是提供保修的。大多數(shù)人我們說話,燃盡之前機器從來沒有把它回來。我們生活在這樣一個社會可悲的是,但它制造的大。社會的另一個事實是我們中有多少人新項目的櫥柜,僅次于最可能的新項目的櫥柜,僅次于喬治·福爾曼風格烤架。我們相信這是由于上述缺點的這種風格的大街離心是迄今為止最購買的一種，這榨汁機處理整個生產(chǎn)制造過程，.整個蘋果,芹菜的整個頭，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,這個功能是方便,但是這個過程仍然破壞果汁,您仍然需要清理每一個玻璃以后被生產(chǎn)作為過濾器障礙物更加迅速。
接下來,我們都知道三角皮帶傳動的重要性。三角皮帶傳動廣泛應用于各種各樣的機器,所以理解和知道如何設計很試驗臺上三角皮帶激勵等三角皮帶和滑輪是兩個最重要的部分三角皮帶驅(qū)動,中心距,滑輪的直徑和滑輪直徑是最基本的參數(shù)三角皮帶傳動三角皮帶驅(qū)動。驅(qū)動皮帶輪和動力輸出輪,我們設計的直徑比速度的基礎。
三角皮帶傳動驅(qū)動皮帶輪和動力輸出皮帶輪和無休止的三角皮帶繞著兩個滑輪。這個三角皮帶驅(qū)動器配有扭矩測量裝置在rpm傳感器分配給驅(qū)動皮帶輪和動力輸出皮帶輪,不斷檢測輪,兩個傳感器與電子控制哪些，決定之間的傳動比傳動和動力輸出裝置檢測到滑輪,校準設備,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估者。
本發(fā)明涉及提供一個三角皮帶驅(qū)動,可以確定現(xiàn)有扭矩在不同驅(qū)動同一負載通過簡單的手段和最優(yōu)轉(zhuǎn)矩現(xiàn)有在不同驅(qū)動同一負載以最優(yōu)的方式,通過簡單的手段和作為的運行部分的函數(shù)，v帶傳動,驅(qū)動輪,動力輸出裝置和三角皮帶,控制并調(diào)整它。
三角皮帶驅(qū)動按照發(fā)明配有扭矩測量裝置,采用三角皮帶在v形帶溝槽的深度滲透的動力和動力輸出裝置滑輪,因此，通常被認為是滑移和沒有考慮在內(nèi),從而造成的可變傳動比以及這個齒輪比率相比,這些不斷變化的函數(shù)驅(qū)動皮帶輪上的負載,與預定的力矩電子設備,評估這對扭矩的變化差異獲得的方式,導致實際轉(zhuǎn)矩分別。
通過這可以在一個簡單的和確定的方式和調(diào)整扭矩;同時檢測并立即解決發(fā)展中問題,過載,磨損等的各種機器和設備驅(qū)動,如農(nóng)業(yè)機械、工業(yè)機械和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,正因為如此,兩個滑輪.T或齒輪的不同轉(zhuǎn)速比的兩個滑輪是通過改變這措施.為了彌補這一行動,或改變傳動比通過傳感器,根據(jù)負載驅(qū)動皮帶輪和他穿透深度的滑輪V帶輪，滑輪不斷發(fā)現(xiàn)通過滑輪的v帶.不斷發(fā)現(xiàn)通過傳感器,和這些數(shù)據(jù)集中到電子設備.由此形成一個傳動比。
空載條件或知道他三角皮帶驅(qū)動負載校準標定裝置的執(zhí)行將RPM或傳動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),其他人可以通過運用現(xiàn)有知識,容易修改和/或調(diào)整等各種應用程序并且沒有離開通用概念和它的具體體現(xiàn),因此,適應和修改等,目的是應該理解的意義和范圍內(nèi)對應披露的化身,是理解詞組或術語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計v形帶激勵等總體設計要求是得到最好的兩個滑輪之間的中心距離. .當然,設計師有幾個知道條件他/她開始設計之前,如驅(qū)動輪的轉(zhuǎn)速、傳動皮帶輪之間的傳動比和動力機械故障輪(或動力輸出輪),電力傳輸和三角皮帶的工作環(huán)境激勵等設計的最終目的是使三角皮帶傳動的最小規(guī)模的會議,所有的工作需求的基礎。
眾所周知,三角皮帶是最重要的三角皮帶傳動的一部分。然而重要理解三角皮帶的設計和選擇,人造絲和橡膠v形帶廣泛用于電力的傳動.v帶是有兩個系列:標準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)點之一是成本低,和輸出功率高，可能增加了操作幾個v帶,身邊的皮帶驅(qū)動應該以同樣的速度伸展為了保持負載同樣分給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)勢是,它包括皮帶槽角，通常從34-38的帶槽的廣泛作用，使機器大量增加牽引力并且由傳送帶傳遞。
而另一個重要部分三角皮帶驅(qū)動輪,它可能用廣泛應用在是鑄鐵、鋼板或模鑄金屬灰色鑄鐵這些材料，當三角皮帶的速度不超過25米/秒,我們應該采用HT150滑輪的材料,當速度是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，當需要的力不是很大時,滑輪也可以用鑄鋁或其他材料制作.皮帶輪由輪緣,網(wǎng)絡和輪中心構成.滑輪是一個市場,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,小皮帶輪傳動皮帶輪,和大用作動力輸出裝置滑輪。
在我們理解常用的v型皮帶傳動的結(jié)構,我們應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,和壓力包括拉伸應力、彎曲應力和離心壓力設計必須使拉力和壓力不超過固定值以避免滑動,我們也應該使發(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度和一個明確的允許值。
接下來,我們應該知道軸、聯(lián)軸器和滾動接觸軸承。
幾乎所有機器包含軸軸最常見的形狀是圓形截面可以是實心或空心(空心軸可能導致重量儲蓄).通常軸有時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度傳輸扭矩和壓力過大。它也足夠扭力tiff,安裝組件不偏離足夠硬,一個安裝組件不過分偏離原來的角位置相對于第二個組件安裝在同一個軸上總體而言,扭轉(zhuǎn)角度軸的長度不應超過或者等于20mm。
軸安裝本質(zhì)通過齒輪等設備和傳輸功率,滑動,凸輪和離合器這些設備介紹部隊試圖彎軸;因此,軸必須足夠嚴格,防止超載的發(fā)生.在設備內(nèi)部,軸的彎曲撓度之間的長度不應超過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)和彎矩的當量載荷.，因為扭矩和彎矩會產(chǎn)生變應力，在許用應力中也應該有一個考慮疲勞現(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，。當直徑大于5英寸時，則采用鍛造毛坯，然后機械加工到所要求的尺寸。輕載時，廣泛采用塑料軸。由于塑料是電的不是導體，在電器中用它做軸比較安全。
齒輪和皮帶輪等零件通過鍵連接在軸上。在對鍵及軸上與之相應的鍵槽進行設計時，必須進行認真的計算。例如,應力集中發(fā)生在軸鍵槽,由于鍵槽存在使軸的橫截面面積間隙，會料被進一步削弱了軸的強度。
如果軸以速度轉(zhuǎn)動，,將會發(fā)生強烈的振動，可能會毀壞整臺機器。,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)驗來說，工作速度和臨界轉(zhuǎn)速之間的應該至少相差20%。
軸設計的另一個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)軸器來實現(xiàn)的。
聯(lián)軸器是用來把兩相鄰的軸端聯(lián)接起來的裝置,在機械結(jié)構中，聯(lián)軸器被用來實現(xiàn)兩根轉(zhuǎn)軸之間的半永久聯(lián)接。在機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，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的軸，可以采用分段的方式將其制造出來，然后采用剛性聯(lián)軸器將各段聯(lián)接起來。一種常用的聯(lián)軸器是由兩個配對的法蘭組成，這兩個法蘭盤借助靠鍵傳動的軸套聯(lián)接到相鄰兩節(jié)軸的兩端，然后用螺栓穿過法蘭聯(lián)接起來形成剛性接頭。相互聯(lián)接的兩根軸通常是靠法蘭面的槽口來對準的,
在把屬于不同的設備（例如一個電動機和一個變速箱）的聯(lián)聯(lián)接起來的時候，要把這些軸精確地對準是比較困難的，此時可以采用彈性聯(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而不至于相互干擾。彈性聯(lián)軸器也可以用來減輕一根軸傳動另一根軸上的沖擊載荷和振動的強度。
幾乎所有軸都裝有滾動軸承。對于球軸承和滾子軸承，一個機器設計員應該考慮下面五個方面：:(a)壽命與負載的關系;(b)剛度、也就是在荷載下的變形量;(c)摩擦:(d)磨損;(e)噪音。對于中等負載和轉(zhuǎn)速選擇一個標準的軸承，通常都可以抱著其令人滿意的工作性能。當載荷較大時，軸承變得重要起來。在轉(zhuǎn)速高的場合需要有專門的冷卻裝置，而這啃會增加摩擦阻力。磨損主要由于污染物的進入引起的，必須選用密封裝置以防止周圍環(huán)境的不良影響。
因為大批量生產(chǎn)這種方式?jīng)Q定了球軸承和滾子軸承不但質(zhì)量高，而且價格低，因而機器設計人員的任務是選擇而不是設計軸承。滾動接觸軸承通常是采用硬度大約900HV、整體淬火的剛來制造的。但在許多機構上不使用專門的套圈，而將相互作用的表面淬硬到大約600HV。滾動軸承由于在工作中會產(chǎn)生高的應力，其主要失效形式是金屬疲勞，這一點并不奇怪，目前正在進行大量的工作以求改進這種軸承的可靠性。通常設計軸承中將會有90%的軸承具有超過一百萬轉(zhuǎn)的壽命。
不承受責任的事實基本設計球和滾子軸承的軸承制造商,機器設計者必須從正確的升值的義務由軸承,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重要的,因為他們的結(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重的麻煩擔憂，經(jīng)常位于軸向內(nèi)部競賽對接肩膀。此時,半徑是重要為避免應力集中和球比賽提供了提供了一個半徑或倒角允許空間。
設計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)量意味著可以應用于軸承的負荷,這是固定的或輕微的旋轉(zhuǎn)運動,而不會影響它的運行品質(zhì)隨后轉(zhuǎn)動motion.This已經(jīng)由實踐經(jīng)驗時的負載應用到軸承導致的總變形滾動體和滾道接觸在任何時候不超過0.01%的滾動體直徑.這相當于直徑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?shù)母糸_，許多軸才能成功的實現(xiàn)它們的作用,在某些情況下，必須保護環(huán)境，使其不受潤滑劑和軸承便面磨損生產(chǎn)物的污染，軸承設計的一個重要組成部分是使密封裝置起到應有作用。此外，對摩擦學研究員來說，為了任何目的而應用于運動零部件上的密封裝置都是他們感興趣的。因為密封裝置是軸承系統(tǒng)部分，只有根據(jù)適當軸承理論才能設計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。
減速器是一個動態(tài)的交流機構,利用齒輪的速度轉(zhuǎn)換器,減速電機轉(zhuǎn)速的旋轉(zhuǎn)數(shù),和有更大的扭矩機構.減速器的作用:
(1) 同一時間，速度提高輸出扭矩,輸出轉(zhuǎn)矩比由減速電機輸出,但要注意超過額減速的同時降低了負載的慣量，慣量的減少為減速比的平方。大家可以看一下一般的電機都有一個慣量數(shù)值。
(2) 定扭矩減速器。
通用斜齒輪減速器減速機(包括平行軸斜齒輪減速機,蝸輪減速機、斜齒輪減速機等。)行星齒輪減速機、擺線減速機、蝸輪減速機、行星摩擦無級變速機械機器。
第一,國內(nèi)許多由齒輪傳動減速器,蝸桿傳動為主,但功率和負載比通常很小,或者速度比大而機械效率過低的問題，另外,材料的質(zhì)量和技術水平也有很多弱點,大規(guī)模的減速齒輪的問題特別突出，壽命不是很長，國內(nèi)使用大型減速齒輪(約50 kw),許多從國外(例如區(qū)別,德國等等)進口的60年代開始幾齒減速機等等,不同傳播,擺線銷齒輪傳動,泛音傳輸生產(chǎn)具有傳動比大,體積小,機械效率高等優(yōu)點。但它傳播理論限制,不能傳輸過大的功率，功率一般都必須小于40千瓦,因為在傳播理論上,技術水平和材料質(zhì)量方面沒有突破,因此,還不能從根本上解決傳動功率大,傳動比大,,體積小,重量輕,,機械效率高等這些要求。90年代的初期,國內(nèi)出現(xiàn)三環(huán)（齒輪）的減速器，是一種齒輪傳動減速裝置,可以實現(xiàn)大傳動比,傳動負載能力也比較大。它體積和重量都是輕于定軸齒輪減速器,結(jié)構簡單,效率也高因為這個減速齒輪三軸平行結(jié)構簡單,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，這個在使用上沒有許多不便，北京理工大學研制成功的內(nèi)平動齒輪減速器，不僅具有三環(huán)減速器的優(yōu)點，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，處于國內(nèi)領先地位，國內(nèi)有少數(shù)高等學校和廠礦企業(yè)對齒輪傳動中的某些原理做些研究工作，發(fā)表過一些研究論文，在利用擺線齒輪作平動減速器開展了一些工作。
（2） 穩(wěn)定運動減速器齒輪的工作原理簡介、穩(wěn)定運動齒輪減速機是指在一對齒輪減速器傳動中，齒輪在平動發(fā)生器的驅(qū)動下作平面平行運動，通過齒廓間的嚙合，驅(qū)動另一個齒輪作定,通過之間的齒廓嚙合,啟動另一個牙齒輪作定軸減速轉(zhuǎn)動，實現(xiàn)減速傳動的作用。平動發(fā)生器可采用平行四邊形機構，或者正旋機構或十字滑塊機構。平動發(fā)生器可以是虛擬的采用平行四邊形機構，也可以采用實體的平行四邊形機構。有實用價值的平動齒輪機構為嚙合齒輪機構，因此又可分為內(nèi)齒輪并做減速轉(zhuǎn)動輸出。該機構也稱三環(huán)減速器。由于內(nèi)齒輪傳動，兩曲柄中心能設置在外齒輪的齒圈內(nèi)部，大大減少了機構整體尺寸。由于外齒輪作平動，兩曲柄中心能設置在外齒輪的齒圈內(nèi)部，大大減少了機構整體尺寸。由于內(nèi)齒輪機構傳動效率高、體積小、輸入輸出同軸線，故有廣泛的應用前景。
（3） 該項目技術特點和關鍵性功能的新的穩(wěn)定的“動作”減速機齒輪和國內(nèi)外有減速機齒輪相比,具有以下特點:(1)傳動比范圍大,自I= 10,起可能達到最達的幾千I，若制造大速傳動比的減速器,則顯示了這種齒輪減速器的優(yōu)點。(2)傳動功率范圍大，并可與電動機連接一體制造。(3)結(jié)構簡單,體積小,重量是輕，比,現(xiàn)有的機齒輪減速器減少1/3左右。(4)機械效率很高。(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。
【1】、吉川,“分析和控制冗余機器人的“機械技術研究:第一個國際研討會(m·布雷迪和r .保羅eds)(麻省理工學院出版社、劍橋、質(zhì)量)(1984)439 - 439頁。
【2】、克萊恩,“動冗余機械手避障在動態(tài)變化的環(huán)境中“。機器人研究1、3號109 - 117(1985)。
列日瓦“自動監(jiān)控的配置和多體的行為機制”IEEE反式。在系統(tǒng)中,人,Cybern。SMC-7,12號,868 - 871(1977)。
3Chirikjian和J.W.布爾迪克“避障算法hyper-redundant操縱者，機械設計及其自動化,辛辛那提(1990年5月)第625 - 631頁。
【3J】.K.索爾茲伯里,J.J.克雷格的手:力控制和運動學問題“Int。1。機械設計技術研究1、第一4-17(1982)。
【4】Dubey r和J.Y.S. Luh,“機械設備控制與自動化,羅利(1987年3月),頁1066 - 1072。
【5】、7W.K. K.W. Jeong、鐘、y . Youm》“發(fā)展POSTECH 7自由度直接驅(qū)動設計”3日ISRAM Conf . .溫哥華(7月。1990)頁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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