【正文】 I 摘 要 本設計的任務是設計一臺用于轎車上的 FR 式的手動變速器。本設計采用中間軸式變速器，該變速器具有兩個突出的優(yōu)點：一是其直接檔的傳動效率高，磨損及噪聲也最?。欢窃邶X輪中心距較小的情況下仍然可以獲得較大的一檔傳動比。 根據(jù)轎車的外形、輪距、軸距、最小離地間隙、最小轉彎半徑、車輛重量、滿載重量以及最高車速等參數(shù)結合自己選擇的適合于該轎車的發(fā)動機型號可以得出發(fā)動機的最大功率、最大扭矩、排量等重要的參數(shù)。再結合某些轎車的基本參數(shù)，選擇適當?shù)闹鳒p速比。根據(jù)上述參數(shù)，再結合汽車設 計、汽車理論、機械設計等相關知識，計算出相關的變速器參數(shù)并論證設計的合理性。 它功用是：①改變傳動比，擴大驅動輪轉矩和轉速的變化范圍，以適應經常變化的行駛條件，如起步、加速、上坡等，同時使發(fā)動機在有利的工況下工作；②在發(fā)動機旋轉方向不變的前提下，使汽車能倒退行駛；③利用空檔，中斷動力傳遞，以使發(fā)動機能夠起動、怠速，并便于發(fā)動機換檔或進行動力輸出。這臺變速器具有五個前進檔（包括一個超速檔五檔）和一個倒檔，并通過鎖環(huán)式同步器來實現(xiàn)換檔。 關鍵詞： 變速器 ，鎖環(huán)式同步器，傳動比，中間軸，第二軸， 齒輪 II Abstract The duty of this design is to design a FR type manual transmission used in the saloon,It’s the countershafttype transmission transmission has two prominent merits: Firstly,the transmission efficiency of the direct drive keeps off high, the attrition and the noise are also slightest。Secondly ,it’s allowed to obtain in the biger gear ratio of the first gear when the center distance is smaller. According to the contour,track， wheel base， the smallest ground clearance,the smallest turning radium,the vehicles weight, the allup weight as well as the highest speed and so on, union the choosing engine model we can obtain the important parameters of the max power,the max torque, the displacement and so on. According to the basic parameters of the certain saloon,choose the suitable final drive to the above parameters,bining the knowledge of automobile design, automobile theory, machine design and so on, calculate the correlated parameters of the gearbox and proof the rationality of the design. Its function is:① Changing gear ratio,expanding the torque of the driving wheel and the range of the rotational speed,to adapt the travel condition which frequently changes, like start, acceleration, climbing and so on, simultaneously causes the engine to work under the advantageous operating mode。② Under the premise of the invariable rotation, enables the automobile to travel back。③ Using neutral, severances the power transmission, to make the engine start, idle, and is advantageous for the engine to shift gears or to carry on the dynamic output. This gearbox has five (including over drive— fifth gear) and a reverse gear, and through the inertial type of synchronizer to realize shift gears. Key word ： transmission, inertial type of synchronizer,gear ratio, countershaft,second axis, gear 目 錄 第 1 章 變速器的概述 ................................................................................................. 1 變速器功用及設計要求 ................................................................................. 1 汽車變速器的功用 ................................................................................ 1 變速器的設計要求 ................................................................................ 1 設計任務及主要數(shù)據(jù) ..................................................................................... 2 第 2 章 變速器的選擇及主要零件設計 ..................................................................... 2 變速器的選擇 ................................................................................................. 2 兩軸式變速器與三軸式變速器 ............................................................. 3 倒檔傳遞方案 ................................................................................................. 5 變速器主要零件的分析 ................................................................................. 5 齒輪型式 ................................................................................................ 6 換擋結構形式 ........................................................................................ 6 軸承形式 ......................................................................................................... 7 傳動方案的最終設計 ..................................................................................... 7 第 3 章 變速器傳動機構的計算 ................................................................................. 8 變速器 主要參數(shù)的選擇 ................................................................................. 8 檔位數(shù)的確定及傳動比初選 ................................................................ 8 中心距的確定 ........................................................................................ 8 傳動零件的設計 .................................................................................... 9 齒輪材料、壓力角 α、螺旋角 β和齒寬 b.......................................... 9 各檔齒輪參數(shù)的確定 .......................................................................... 10 變速器齒輪的強度計算 ............................................................................... 13 齒輪的損壞原因及形式 ...................................................................... 13 齒輪的強度計算與校核 ...................................................................... 13 齒輪接觸強度的校核 .......................................................................... 15 第 4 章 變速器軸的強度計算與校核 ....................................................................... 17 變速器軸的結構和尺 .................................................................................... 17 軸的結構 .............................................................................................. 17 確定軸的尺寸 ...................................................................................... 18 軸的校核 ....................................................................................................... 18 第一軸