【正文】 8齒。因此在結(jié)構(gòu)設計上應盡量增大各過渡部分的圓角半徑，這對減小應力集中很有效。從節(jié)約較稀有的金屬、降低制造成的目標出發(fā)，采用中碳鋼（40鋼、45鋼）制造 半軸是發(fā)展趨勢，國外已多有采用。半軸的熱處理過去都采用調(diào)質(zhì)處理的方法，調(diào)質(zhì)后要求桿部硬度為388～444HB（凸緣部分的硬度允許降至248HB）。這種處理方法能保證半軸表面有適當?shù)挠不瘜?。?章 驅(qū)動橋殼設計驅(qū)動橋殼的功用是支承并保護主減速器、差速器和半軸等，使左右驅(qū)動車輪的軸向相對位置固定；并和從動橋一起支承車架及汽車的各總成質(zhì)量；汽車行駛時，承受由車輪傳來的路面反作用力和力矩，并經(jīng)懸架傳給車架。2） 保證足夠的離地間隙。4) 保證主減速器的拆裝、調(diào)整、維修和保養(yǎng)方便。驅(qū)動橋殼從結(jié)構(gòu)上可分為整體式橋殼和分段橋殼兩類。按制造工藝的不同又可分為多種形式，常見的為整體鑄造、鋼板沖壓焊接式、中段鑄造兩端壓入鋼管和鋼管擴張成形等形式。但其簧下質(zhì)量較大，對汽車的行駛平順性有不利的影響。2)分段式橋殼一般分為兩段，由螺栓連成一體。拆檢主減速器時，必須把整個驅(qū)動橋從汽車上拆卸下來，目前已很少采用。作用在左右驅(qū)動車輪上的轉(zhuǎn)矩所引起的地面對左、右驅(qū)動車輪的最大切向反作用力共為 = 式中：——發(fā)動機最大轉(zhuǎn)矩； ——變速器一擋傳動比； ———驅(qū)動橋的主減速比； ——傳動系的傳動效率； ——驅(qū)動車輪的滾動半徑。=Nm危險斷面處為圓管形則 從而危險斷面處靜彎曲應力為，滿足要求?！?50=25000mm——軸傳遞的功率，＝132KW；——軸的轉(zhuǎn)速，＝1600r/min；［］——軸材料的許用扭剪應力，軸選用45鋼，［］＝30～40MPa。=(==(=()=()= ＝N== 軸承載荷分析如上圖所示主動齒輪則主動齒輪軸承的徑向載荷為 則第二級軸承得徑向載荷為當量動載荷計算：Q=XR+YA　　　　　　　　　　　　　　　　　　　　　　　式中：X是徑向系數(shù)； Y是軸向系數(shù)；軸承壽命計算：　　　　　　　　　　　　　　　　　式中：C————額定動載荷N； ————溫度系數(shù)； ————載荷系數(shù)； ————壽命指數(shù)。結(jié)論本次設計是對中型貨車驅(qū)動橋為研究對象，對驅(qū)動橋、主減速器、差速器、半軸、橋殼布置進行了設計及計算。并應用MATLAB軟件進行編程。二、設計內(nèi)容：1. 主減速器和差速器的設計在主減速器和差速器的設計中，參數(shù)的選取和計算按照劉惟信主編的《汽車設計》中的計算方法。差速器的設計方法和思路與主減速器的設計基本類似，本次設計選用了工作平穩(wěn)、結(jié)構(gòu)簡單的普通錐齒輪式差速器。此部分對驅(qū)動橋殼的功用和結(jié)構(gòu)方案進行了介紹和分析，采用整體式橋殼，因為其具有較大的強度和剛度，拆裝、調(diào)整方便等優(yōu)點。參考文獻[1] 劉惟信. : 清華大學出版社, 2001[2] 王望予. 汽車設計（: 機械工業(yè)出版社, [3] 陳家瑞. 汽車構(gòu)造（第4版. 北京: 人民交通出版社, [4] 張洪欣 . 汽車設 .北京：機械工業(yè)出版社 . 1999 [5] 紀峻嶺. 傳動軸、差速器、驅(qū)動橋及車橋. 北京: 化學工業(yè)出版社, 2005[6] 汽車標準匯編（第四卷）. 中國汽車技術(shù)中心, 2004 [7] 郝京順. 汽車設計標準資料手冊. 長春: 吉林科技出版社, 1992[8] 吳克堅. 機械設計. 北京: 高等教育出版社, 2003[9] 孫恒, （第六版）. 北京: 高等教育出版社, 2001 [10] 孫志禮. : 東北大學出版社, [11] 龔微寒 . ：人民交通出版社 . 1995 [12] 劉維信. 圓錐齒輪與雙曲面齒輪傳動. 北京：人民交通出版社， 1980[13] 頓德安. , 2000[14] 張玉， 劉平. : 東北大學出版社, [15] 齒輪手冊編委會. 齒輪手冊(第二版).北京：機械工業(yè)出版社， [16] 吉林工業(yè)大學汽車教研室 . ：機械工業(yè)出版社 . 1981[17] 機械設計手冊編委會. 機械設計手冊(3).北京: 機械工業(yè)出版社, [18] 小林明. 汽車工程手冊 (第二分冊).北京: 機械工業(yè)出版社, 1984[19] Reimpell J, stoll H. The Automotive Chassis: Engineering Principles. Warremdale, PA 15096, SA, SAE, 1996 致謝大學四年的美好生活即將以這篇畢業(yè)論文劃上一個句號，回首這段畢業(yè)設計過程，心中滿是感恩之情，在此特地表達誠摯的謝意。我要感謝我的導師XXX老師。他的治學嚴謹?shù)膽B(tài)度、謙虛扎實的工作作風使我深受教育和啟迪，讓我深深感覺到教師的偉大。最后說聲，XXX老師，您辛苦了！最后，我要感謝我的同。在這次設計即將完成之際，我要忠心的謝謝你們！同時也感謝這四年來幫助過我的老師和同學！附 錄1Differential and Rear AxlesThe differential is part of the rearaxlehousing assembly, which includes the differential, rear axles, wheels, and bearings. If the car were to be driven in a straight line without having to make turns, then no differential would be necessary. However, when the car rounds a turn, the outer wheel must travel farther than the inner wheel. The differential permits the two rear wheels to rotate different amounts when the car goes around a turn, while still delivering power to both rear wheels.The rear axles are attached to the wheels and have bevel side gears on their inner ends. The differential case is assembled on the left axle but can rotate on a bearing independently of the differential case supports the differentialpinion gear on a shaft, and this gear meshes with the two bevel gears. The ring gear is attached to the differential case so that the case rotates with the ring gear when the later is driven by the drive driving power enters the differential through the drive pinion on the end of the propeller shaft. The drive pinion is meshed with a large ring gear so that the ring gear revolves with the pinion.Attached to the ring gear (through the differential case) is a differentialpinion shaft on which are assembled two differentialpinion gears. Each rear car wheel has a separate axle, and there are two side gears splined to the inner ends of the two wheel axles. The two differentialpinion gears mesh with these two side gears. When the car is on a straight road, the two differentialpinion gears do not rotate on the pinion shaft, but they do exert pressure on the two side gears so that the side gears turn at the same speed as the ring gear, causing both rear wheels to turn at the same speed, differential case is supported in the carrier by two taperedroller side bearings. This assembly can be adjusted from side to side to provide the proper backlash between the ring gear and pinion and the required side bearing preload. This adjustment is achieved by threaded bearing adjusters on some units and the placement of selective shims and spacers on others.The differential case is supported in the carrier by two taperedroller side bearings. This assembly can be adjusted from side to side to provide the proper backlash between the ring gear and pinion and the required side bearing preload. This adjustment is achieved by threaded bearing adjusters on some units and the placement of selective shims and spacers on others.Transaxle final drive gears provide the means for transmitting transmission output torque to the differential section of the transaxle. The differential section of the transaxle has the same ponents as the differential gears in a RWD axle and basically operate in the same way. The power flow in transversely mounted power trains is in line with the wheels and therefore the differential unit does not need to turn the power 90 degrees.When the car rounds a curve, the outer wheel must turn faster than the inner wheel. To permit this, the two pinion gears rotate on their pinion shaft, transmitting more turning movement to the outer side gear than to the inner side gear. Thus, the side gear on the outerwheel axle turns more rapidly than the side gear on the innerwheel axle. This permits the outer wheel to turn more rapidly while the car is rounding the are two basic types of axle: dead axles and live axle. The dead axle does not rotate。如果直線行車而不轉(zhuǎn)彎，則不需要差速器。差速器保證車轉(zhuǎn)彎時外面輪子的旋轉(zhuǎn)比里面輪子快，同時給兩個后車輪提供動力。差速器在左車軸，但是能在車軸的軸承上獨立旋轉(zhuǎn)。環(huán)行齒輪和差速裝置相連，從而使這個裝置在副齒輪旋轉(zhuǎn)時和環(huán)行齒輪一起旋轉(zhuǎn)。驅(qū)動副齒輪和大的環(huán)行齒輪互相咬合，從而使環(huán)行齒輪和副齒輪一起旋轉(zhuǎn)。每個后車輪上各有一個車軸，兩個車輪的內(nèi)側(cè)邊緣都有兩個齒輪夾板。當車在公路上直線行駛時，兩個差速副齒輪不在副齒輪柄上旋轉(zhuǎn)，但是它們施力于兩個邊緣齒輪，從而使邊緣齒輪和環(huán)行齒輪速度