【正文】 176。鎖止角與錐面在設計時已作了適當選擇，錐面摩擦使得待嚙合的齒套與齒圈迅速同步，同時又會產生一種鎖止作用，防止齒輪在同步前進行嚙合。而不根切的最小變位系數(shù) ξmin 分別為：min0inZf???式中： ——齒頂高系數(shù)。從齒輪強度觀點出發(fā)，每對齒輪應有各自的模數(shù)，而從工藝的觀點出發(fā)，全部齒輪選用一種模數(shù)是合理的，中型貨車模數(shù)取直范圍為 。使用軸向滑動直齒齒輪換擋，會在輪齒端面產生沖擊，齒輪端部磨損加劇并過早損壞，并伴隨著噪聲。常見的手動變速器由鑄鐵或鋁制變速器殼體、軸、軸承、齒輪、同步器和換擋機構組成。最后繪制裝配圖及零件圖。本次設計的是五個前進檔加一個倒檔的中型專用車的變速器。變速器的作用:改變汽車的傳動比,擴大驅動車輪轉矩和轉速的范圍,使發(fā)動機在理想的工況下工作。因此，在齒輪中心距較小的情況下仍然可以獲得大的一擋傳動比，這是三軸式變速器的另一優(yōu)點。（5）變速器的操縱機構裝在變速箱內，由變速叉軸、變速叉、倒塊、自鎖彈簧、自鎖鋼球、互鎖鋼球、互鎖圓柱銷組成。最后，可用調整螺旋角的方法，使各對嚙合齒輪因模數(shù)或齒數(shù)不同等原因而造成的中心距不等現(xiàn)象得以消除。相鄰擋位相互轉換時，應該采取不同操作步驟的道理同樣適用于移動齒輪換擋的情況，只是前者的待接合齒圈與接合套的轉動角速度要求一致，而后者的待接合齒輪嚙合點的線速度要求一致，但所依據(jù)的速度分析原理是一樣的。,螺距為 ～。同步器時間與車型有關,對貨車變速器高擋取 —，抵擋取 —。近年來，單軌式操縱機構應用較多，其優(yōu)點是減少了變速叉軸，各擋同用一組自鎖裝置，因而使操縱機構簡化，但它要求各擋換擋行程相等。因此，取力裝置在專用汽車的設計和制造方面顯得尤為重要。根據(jù)設計的目的、方法和步驟，我在長春第一汽車制造廠實習的時候對解放汽車變速器進行了調研，收集數(shù)據(jù)，然后在圖書館和網(wǎng)上尋找資料。我們會更加努力的學習和工作，在實踐中不斷的收集資料、積累經(jīng)驗，絕不辜負老師對我們的期望。s dynamic performance. It is usually required shifting gears rapidly and conveniently, saving force, and having a higher working efficiency and low working noises.The modern automatic transmission is by far, the most plicated mechanical ponent in today39。變速器采用中間軸式, 換檔形式采用的是同步器換檔和滑移齒輪換擋。其中中置式取力器又包括變速器上蓋取力、變速器側蓋取力、變速器后蓋取力。在振動等條件影響下，操縱機構應保證變速器不自行掛擋或自行脫擋。二軸、中間軸最大直徑可取 d== 126==57mm?中間軸： d/L= 取為 L=315mm二軸： d/L= 取為 L=315mm軸在垂直面內撓度為 ，在水平面為 ，轉角為 ，則cfsf? ； ； ；EILbaFfc321?EILbaFs32???EILabF31??為輪齒齒寬在中間平面上的圓周力， 為齒輪齒寬在中間面上的徑向力。同步環(huán)錐面寬 B 與摩擦錐面的發(fā)熱有關,一般取 B=R鎖/10～R 鎖/14(R 鎖為撥環(huán)半徑)。為了簡化操作，并避免齒間沖擊，可以在換擋裝置中設置同步器?！?6176。第三章 變速器各主要參數(shù)的設計計算 變速器傳動比的確定（1）由最大爬坡度要求的變速器一檔轉動比又 ， ， ，tmaxfiaxF=+emax10taxMiF=r?fmaxF=gcos?iamaxF=fgsin?則 e10aaxMgfcos+inr????（ ） 34i3??輪胎型式取 255/70R45140/137J 12in= 則即半徑為 ， ， ， ，=.9?=???m=9800kgm汽車總質量g重力加速度max?道路最大阻力系數(shù)r驅動車輪的滾動半徑axeT為發(fā)動機最大轉矩0i主減速比傳動系的傳動效率?（2）根據(jù)驅動輪與路面的附著力確定一檔傳動比 emax10MiNr?? ==?? N 驅動輪垂直反力 取整車重量的 65% =～ 道路附著系數(shù) 取 ?由（1） 、 （2）相比較取較小的 故一檔傳動比確定為： 1i= 其它各檔位的傳動比而 ==165各檔傳動比： 1maxi? 23q29 5465 min?1i而 .?各檔之比都小于 ～ 故合格 中心距的初步確定初選中心矩可用下式計算 取整 A=?????式中：A——中心距系數(shù)， 取值范圍 — 取 A=9AKaxeT——發(fā)動機最大轉矩， NmTe3ax1i——變速器一擋傳動比， ?——變速器傳動效率， ?096?求得 A=126mm 軸的直徑的初步確定變速器的軸必須有足夠的剛度和強度。綜上所述中型專用汽車應選用三軸式變速器。實現(xiàn)空擋,中斷發(fā)動機傳遞給車輪的動力,使發(fā)動機能夠起動、怠速。變速器采用中間軸式,換檔形式采用的是同步器和滑移齒輪換檔，使的換檔方便，可靠。由中心矩確定箱體的長度、高度和中間軸及二軸的軸徑，然后對中間軸和各擋齒輪進行校核。而在高速時,讓傳動比小的齒輪副工作。直齒圓柱齒輪用于一擋和倒擋。第一軸花鍵部分直徑可按下式初選： 3maxeTKD?式中：K—經(jīng)驗系數(shù)，K=，取 K=4—發(fā)動機最大轉矩 ,求得 D= 齒輪模數(shù)的確定本變速器設計一、倒擋為直齒，其它擋為斜齒，選取齒輪模數(shù)要保證齒輪有足夠的剛度，同時兼顧它對噪聲和質量的影響，減少模數(shù)、增加齒寬會使噪聲降低，反之則能減輕變變速器的質量。對于本次設計，當直齒輪 17 時，采用正變位，和它相嚙合的齒輪則采用負minZ?變位。慣性式同步器是依靠摩擦作用實現(xiàn)同步的，在其上面設有專設機構保證接合套與待接合的花鍵齒圈在達到同步之前不可能接觸，從而避免了齒間沖擊。4 同步器鎖止角的確定要使同步環(huán)在同步階段中鎖止,必須滿足鎖止條件:tanβ≥R 錐 μR 鎖sinα。a 、b～為齒輪上作用力矩與支座 A、B 的距離，L～為支座間的距離。起到了自鎖的作用。它由取力機構齒輪箱、操縱機構、傳動軸、泵架等組成。操縱機構還設有自鎖和互鎖裝置。 which causes the drive wheels to turn in the opposite direction allowing you to back up. Finally, there is the Park position. In this position, a latch mechanism (not unlike a deadbolt lock on a door) is inserted into a slot in the output shaft to lock the drive wheels and keep them from turning, thereby preventing the vehicle from rolling. There are two basic types of automatic transmissions based on whether thevehicle is rear wheel drive or front wheel drive. On a rear wheel drive car, the transmission is usually mounted to the back of the engine and is located under the hump in the center of the floorboard alongside the gas pedal position. A drive shaft connects the rear of the transmission to the final drive which is located in the rear axle and is used to send power to the rear wheels. Power flow on this system is simple and straight forward going from the engine, through the torque converter, then through the transmission and drive shaft until it reaches the final drive where it is split and sent to the two rear wheels. On a front wheel drive car, the transmission is usually bined with the final drive to form what is called a transaxle. The engine on a front wheel drive car is usually mounted sideways in the car with the transaxle tucked under it on the side of the engine facing the rear of the car. Front axles are connected directly to the transaxle and provide power to the front wheels. In this example, power flows from the engine, through the torque converter to a large chain that sends the power through a 180 degree turn to the transmission that is along side the engine. From there, the power is routed through the transmission to the final drive where it is split and sent tothe two front wheels through the drive axles. There are a number of other arrangements including front drive vehicles where the engine is mounted front to back instead of sideways and there are other systems that drive all four wheels but the two systems described here are by far the most popular. A much less popular rear drive arrangement has the transmission mounted directly to the final drive at the rear and is connected by a drive shaft to the torque converter which is still mounted on the engine. This system is found on the new Corvette and is used in order to balance the weight evenly between the front and rear wheels for improved performance and handling. Another rear drive system mountseverything, the engine, transmission and final drive in the rear. This rear enginearrangement is popular on the Porsche.Transmission Components The modern automatic transmission consists of many ponents and systems that are designed to work together in a symphony of clever mechanical, hydraulic and electrical technology that has evolved over the years into what many mechanically inclined individuals consider to be an art form. The cyeloid driveThe cyeloid drive has the essential advnatages sueh as Wide rnage of tranmsission ratio， eompact surtcture，high relibaility nad long wokrnig lief，So It gets borad