捷达汽车变速器设计.doc

捷达汽车变速器设计 摘 要： 变速器用来改变发动机传到驱动轮上的转矩和转速，是汽车总成部件中的重要组成部分，是主要的传动系统。变速器的结构要求对汽车的动力性、燃料经济性、换档操纵的可靠性与轻便性、传动平稳性与效率等都有直接的影响。 Jetta transmission Abstract:Transmission to change the engine reached on the driving wheel torque and speed, Automotive transmission parts in the automobile assembly of an important part of the main drive system. Transmission of the power structure of the vehicle, economy, manipulation of the reliability and portability, the smooth drive and have a direct impact on efficiency. The design is based on Jetta transmission, combined with mechanical transmission design. At first, I will give a summary of the current situation and the tendency of development of the vehicle transmission, and introduce the latest development state in the field of the transmission.The second, I will compare the transmitting scheme of different transmission, and choose a better structure scheme.Next, I will do some mechanic analyses, strength, stiffness check of the shafts and gears, which are the important parts of the transmission, and choose appropriate materials and heat treatment. At last, I will introduce the operation mechanism and the synchronizer, which plays an important role in changing gear. I will give an account of the type, operation, design procedure and major parameter of the synchronizer.At the supplement, I will write some thing like formula, tableau graph and so on. It may be helpful for the future design. Keywords: Transmission；Gear ratio；Gear；Shaft；Desig 目 录 1绪 论 1 1.1 概述 1 1.1.1 变速器的发展现状 3 1.1.2 研究的目的、依据和意义 3 1.1.3 研究的方法 4 2 变速器主要参数的选择与计算 5 2.1设计初始数据 5 2.2变速器各挡传动比的确定 5 2.3变速器传动方案的确定 7 2.4中心距A的确定 8 2.5齿轮参数 8 2.5.1 模数 8 2.5.2 压力角 9 2.5.3 螺旋角 9 2.5.4 齿宽 9 2.5.5 齿顶高系数 10 2.6本章小结 10 3 齿轮的设计计算与校核 11 3.1齿轮的设计与计算 11 3.1.1 各挡齿轮齿数的分配 11 3.1.2齿轮材料的选择原则 20 3.1.3计算各轴的转矩 21 3.2轮齿的校核 21 3.2.1轮齿弯曲强度计算 21 3.2.2轮齿接触应力σj 25 3.3本章小结 30 4 轴的设计与计算及轴承的选择与校核 31 4.1轴的设计计算 31 4.1.1 轴的工艺要求 31 4.1.2 初选轴的直径 31 4.1.3 轴的强度计算 32 4.2轴承的选择及校核 36 4.2.1输入轴的轴承选择与校核 36 4.2.2 输出轴轴承校核 3