汽车变速器是汽车总成部件中的重要组成部分，是主要的传动系统。变速器的结构对汽车的动力性、经济性、操纵的可靠性与轻便性、传动的平稳性与效率等都有直接影响。

本设计是依据时代牌货车BJ1020V0J31的相关参数，通过各部分参数的选择和计算，设计出一个令自己满意的手动变速器。其设计的基本内容是有：变速器传动机构布置方案，变速器主要参数的选择，变速器各挡传动比确定以及分配，变速器各挡齿轮齿数分配，变速器齿轮的设计与计算，变速器轴和轴承的设计计算，操纵机构设计，以及手绘制装配图和零件图等八项内容。在设计过程中主要需解决的问题有：变速器各参数的确定，变速器齿轮的设计、计算及校核，变速器轴的设计、计算及校核和轴承的校核计算，操纵机构设计以及绘制装配图及零件图五大主要问题。

随着我国汽车行业的迅猛发展，人们对汽车的需求也越来越高。通过对轿车变速器的设计，我了解到变速器在汽车结构中具有着重要的作用，因此变速器结构的改进对汽车行业的发展与进步具有深远的意义。

-Automobile transmission is an important part of automobile assembly components of the transmission system is the main. Have a direct effect on the structure of transmission of the automobile s power, economy, reliability and portability, the manipulation of the transmission stability and efficiency etc.

The design is based on the relevant parameters of Era BJ1020V0J31, through the selection and calculation of the parameters, design a satisfied manual transmission. The basic content of the design are: transmission mechanism arrangement scheme, the main parameters of transmission choices, gear ratio transmission and distribution, transmission of the gear tooth number distribution, design and calculation of transmission gear, design and calculation of transmission shaft and bearing design, operation mechanism, and hand-painted for the assembly and parts drawing and other eight items.In the design process of the main problems to be solved are: to determine parameters of the transmission,