【正文】 a 90deg. Shaft angle.When gears are to be used to transmit motion between intersecting shaft, some of bevel gear is required. Although bevel gear are usually made for a shaft angle of 90 deg. They may be produced for almost any shaft angle. The teeth may be cast, milled, or generated. Only the generated teeth may be classed as accurate. In a typical bevel gear mounting, one of the gear is often mounted outboard of the bearing. This means that shaft deflection can be more pronounced and have a greater effect on the contact of teeth. Another difficulty, which occurs in predicting the stress in bevelgear teeth, is the fact the teeth are tapered. Straight bevel gears are easy to design and simple to manufacture and give very good results in service if they are mounted accurately and positively. As in the case of squr gears, however, they bee noisy at higher values of the pitchline velocity. In these cases it is often good design practice to go to the spiral bevel gear, which is the bevel counterpart of the helical gear. As in the case of helical gears, spiral bevel gears give a much smoother tooth action than straight bevel gears, and hence are useful where high speed are encountered.It is frequently desirable, as in the case of automotive differential applications, to have gearing similar to bevel gears but with the shaft offset. Such gears are called hypoid gears because their pitch surfaces are hyperboloids of revolution. The tooth action between such gears is a bination of rolling and sliding along a straight line and has much in mon with that of worm gears.A shaft is a rotating or stationary member, usually of circular cross section, having mounted upon it such elementsas gears, pulleys, flywheels, cranks, sprockets, and other powertransmission elements. Shaft may be subjected to bending, tension, pression, or torsional loads, acting singly or in bination with one another. When they are bined, one may expect to find both static and fatigue strength to be important design considerations, since a single shaft may be subjected to static stresses, pletely reversed, and repeated stresses, all acting at the same time.The word “shaft” covers numerous variations, such as axles and spindles. Anaxle is a shaft, wither stationary or rotating, nor subjected to torsion load. A shirt rotating shaft is often called a spindle.When either the lateral or the torsional deflection of a shaft must be held to close limits, the shaft must be sized on the basis of deflection before analyzing the stresses. The reason for this is that, if the shaft is made stiff enough so that the deflection is not too large, it is probable that the resulting stresses will be safe. But by no means should the designer assume that they are safe。GEAR AND SHAFT INTRODUCTIONAbstract: The important position of the wheel gear and shaft can39。這些磁極板之間有磁粉混合物潤(rùn)滑。該內(nèi)軸件，在它的周邊加工了數(shù)個(gè)平面。這些離合器通常用彈簧加載，以使得在達(dá)到預(yù)定的力矩時(shí)釋放。雖然強(qiáng)制離合器不像摩擦接觸離合器用的那么廣泛，但它們確實(shí)有很重要的運(yùn)用。各種強(qiáng)制接觸離合器之間最大的區(qū)別與夾爪的設(shè)計(jì)有關(guān)。各種各樣的離合器和制動(dòng)器可作如下分類：1． 輪緣式內(nèi)膨脹制凍塊；2． 輪緣式外接觸制動(dòng)塊；3． 條帶式；4． 盤型或軸向式；5． 圓錐型；6． 混合式。這是一個(gè)靜力學(xué)問題。簡(jiǎn)化摩擦離合器或制動(dòng)器的動(dòng)力學(xué)表達(dá)式中，各自以角速度w1和w2運(yùn)動(dòng)的兩個(gè)轉(zhuǎn)動(dòng)慣量I1和I2，在制動(dòng)器情況下其中之一可能是零，由于接上離合器或制動(dòng)器而最終要導(dǎo)致同樣的速度。這樣，它是一個(gè)檢驗(yàn)已經(jīng)設(shè)計(jì)好了的軸的或者發(fā)現(xiàn)具體軸在運(yùn)轉(zhuǎn)中發(fā)生損壞原因的好方法。但決不意味著設(shè)計(jì)者要保證；它們是安全的，軸幾乎總是要進(jìn)行計(jì)算的，知道它們是處在可以接受的允許的極限以內(nèi)。心軸也是軸，既可以旋轉(zhuǎn)也可以靜止的軸，但不承受扭轉(zhuǎn)載荷。在軸上安裝像齒輪，皮帶輪，飛輪，曲柄，鏈輪和其他動(dòng)力傳遞零件。這樣的齒輪機(jī)構(gòu)叫做準(zhǔn)雙曲面齒輪機(jī)構(gòu)，因?yàn)樗鼈兊墓?jié)面是雙曲回轉(zhuǎn)面。直齒錐齒輪易于設(shè)計(jì)且制造簡(jiǎn)單，如果他們安裝的精密而確定，在運(yùn)轉(zhuǎn)中會(huì)產(chǎn)生良好效果。僅就滾齒而言就可達(dá)一級(jí)精度。蝸桿上的齒斜角度通常很大，而蝸輪上的則極小，因此習(xí)慣常規(guī)定蝸桿的導(dǎo)角，那就是蝸桿齒斜角的余角；也規(guī)定了蝸輪上的齒斜角，該兩角之和就等于90度的軸線交角。單包圍機(jī)構(gòu)就是蝸輪包裹著蝸桿的一種機(jī)構(gòu)。蝸桿和蝸輪通常是用于向垂直相交軸之間的傳動(dòng)提供大的角速度減速比。然而當(dāng)該齒的斜角不相等時(shí)，如果兩個(gè)齒輪具有相同齒向的話，大斜角齒輪應(yīng)用作主動(dòng)齒輪。交錯(cuò)軸斜齒輪與斜齒輪之間在被安裝后互相捏合之前是沒有任何區(qū)別的。當(dāng)兩個(gè)或更多個(gè)單向齒斜齒輪被在同一軸上時(shí)，齒輪的齒向應(yīng)作選擇，以便產(chǎn)生最小的軸向推力。斜齒輪使軸的軸承承受徑向和軸向力。斜齒輪輪齒的初始接觸是一點(diǎn)，當(dāng)齒進(jìn)入更多的嚙合時(shí)，它就變成線。齒的形狀是一濺開線螺旋面。而在錐齒輪的情況中各回轉(zhuǎn)軸線互相不平行。所以我們對(duì)齒輪和軸的了解和認(rèn)識(shí)必須是多層次多方位的。在此，請(qǐng)?jiān)试S我對(duì)說(shuō)一聲：“老師，您辛苦了！”再次感謝他們。本設(shè)計(jì)是在老師耐心指導(dǎo)下多次修改完成的。短短的時(shí)間里，我學(xué)到了很多的東西。而且大大提高了動(dòng)手的能力，使我充分體會(huì)到了在創(chuàng)造過程中探索的艱難和成功時(shí)的喜悅。此外，還得出一個(gè)結(jié)論：知識(shí)必須通過應(yīng)用才能實(shí)現(xiàn)其價(jià)值！有些東西以為學(xué)會(huì)了，但真正到用的時(shí)候才發(fā)現(xiàn)是兩回事，所以我認(rèn)為只有到真正會(huì)用的時(shí)候才是真的學(xué)會(huì)了。自己要學(xué)習(xí)的東西還太多，以前老是覺得自己什么東西都會(huì)，什么東西都懂，有點(diǎn)眼高手低。在不斷的努力下我的畢業(yè)設(shè)計(jì)終于完成了。畢業(yè)設(shè)計(jì)總結(jié)通過此次畢業(yè)設(shè)計(jì)，我不僅把知識(shí)融會(huì)貫通，而且豐富了大腦，同時(shí)在查找資料的過程中也了解了許多課外知識(shí)，開拓了視野，認(rèn)識(shí)了將來(lái)電子的發(fā)展方向，使自己在專業(yè)知識(shí)方面和動(dòng)手能力方面有了質(zhì)的飛躍。驗(yàn)算如下：1) 求相對(duì)軸向載荷對(duì)應(yīng)的e值與Y值。3. 疲勞強(qiáng)度的校核查表得： 材料靈敏性系數(shù)為 有效應(yīng)力集中系數(shù)為：尺寸系數(shù)，扭轉(zhuǎn)尺寸系數(shù)。渦輪的線型為ZA型。 167。根據(jù)表中數(shù)據(jù)，取，于是得：輸入軸 輸出軸 應(yīng)此，我取輸入，輸出軸端最小軸徑相同，同為25mm，根據(jù)最小軸徑根據(jù)公式，計(jì)算出應(yīng)小于聯(lián)軸器公稱轉(zhuǎn)矩條件，查標(biāo)準(zhǔn)GB/T5014——2003，選取了彈性柱銷聯(lián)軸器3. 初步選擇滾動(dòng)軸承。 輸入軸的設(shè)計(jì)與計(jì)算1. 軸上零件的定位為了防止軸上零件受力時(shí)發(fā)生沿軸向或周向東相對(duì)運(yùn)動(dòng)，軸上零件除了有游動(dòng)或空轉(zhuǎn)的要求外，都必須進(jìn)行軸向和周向定位，以保證其準(zhǔn)確的工作位置所以我采用定位軸肩、套筒、軸端擋圈、軸承端蓋和螺母等來(lái)保證。槽型曲線可以為阿基米德螺旋線，也可以用圓弧代替，我選圓弧方法，變速槽中心線必須通過A,B,C三點(diǎn)，它們的極坐標(biāo)分別為： 定出A,B,C三點(diǎn)后，用作圖法作出A,B，C三點(diǎn)的圓弧半徑R及圓心 傳動(dòng)比與渦輪轉(zhuǎn)角呈線性變化，則槽型曲線為： 與呈線性變化，故有 邊界條件有： 即 （A） （B） （C） 聯(lián)立解式（A）和（C）得 故 我設(shè)計(jì)的是對(duì)稱調(diào)速，=3 所以 即調(diào)速渦輪轉(zhuǎn)角3/4用于升速調(diào)速，而1/4用于降速調(diào)速，所以我采用單頭蝸桿，以增強(qiáng)自索性，避免自動(dòng)變速。 應(yīng)此 加壓盤V行槽傾角 取= 加壓鋼球按經(jīng)驗(yàn)公式取得 =驗(yàn)算接觸強(qiáng)度均不足，故改用腰型滾子8個(gè)，取滾子軸向截面內(nèi)圓弧半徑=8cm，橫向中間截面半徑r=。摩擦輪與加壓盤之間還有預(yù)壓碟行彈簧并襯以調(diào)整墊圈。 鋼球支撐軸承的極限轉(zhuǎn)角： （增速方向） （減速方向） 4. 計(jì)算確定傳動(dòng)鋼球的直徑 按手冊(cè)由查得，帶入公式 按上表鋼球規(guī)格圓整取 錐輪直徑 圓整取 我畫圖時(shí)取為147mm則 驗(yàn)算接觸應(yīng)力 = 應(yīng)此在許用接觸應(yīng)力范圍內(nèi)，故可用。第三章 鋼球外錐式無(wú)級(jí)變速器部分零件的設(shè)計(jì)與計(jì)算 167。如圖23為其特性曲線：圖 23 無(wú)級(jí)調(diào)速的特性曲線167。此種變速器應(yīng)用廣泛。一般用于機(jī)床和紡織機(jī)械等.下圖是RC型變速器的機(jī)械特性：167。由于采用兩軸線平行的長(zhǎng)錐替代了兩對(duì)分離輪，并且通過移動(dòng)鋼環(huán)來(lái)進(jìn)行變速，所以結(jié)構(gòu)特別簡(jiǎn)單。 畢業(yè)設(shè)計(jì)內(nèi)容和要求畢業(yè)設(shè)計(jì)類容：小功率機(jī)械無(wú)級(jí)變速器結(jié)構(gòu)的設(shè)計(jì)；比較和選擇合適的方案， 無(wú)級(jí)變速器變速器的結(jié)構(gòu)設(shè)計(jì)與計(jì)算；對(duì)關(guān)鍵部件進(jìn)行強(qiáng)度和壽命校核。山西大同齒輪集團(tuán)配套市場(chǎng)主要在8～10t , 變速器產(chǎn)品型譜逐步細(xì)化,產(chǎn)品的針對(duì)性越來(lái)越強(qiáng)。這足以說(shuō)明國(guó)內(nèi)的重型車變速器企業(yè)仍然很渺小,在技術(shù)方面仍然有很長(zhǎng)的路要走。但從當(dāng)今重型車變速器的發(fā)展情況來(lái)看,在新產(chǎn)品開發(fā)上國(guó)內(nèi)重型車變速器仍然走的是一般性的開發(fā)過程,沒有真正的核心技術(shù)產(chǎn)品。有人主張直接從國(guó)外引進(jìn)先進(jìn)的汽車自動(dòng)變速箱技術(shù)，不料國(guó)外所有相關(guān)公司都想直接從國(guó)外把汽車自動(dòng)變速箱產(chǎn)品銷售到中國(guó)市場(chǎng)或者在中國(guó)建立獨(dú)資企業(yè)就地生產(chǎn)銷售產(chǎn)品，不愿與中國(guó)的企業(yè)合