1、 I 摘 要 变速器是汽车的主要组成部分,其功能是改变传动比、 改变驱动轮的扭矩和转 动方向。变速器能在发动机旋转方向不变的前提下，使汽车倒退行驶，而且利用 挡位可以中断动力的传递。所以变速器的结构设计的合理性直接影响到汽车动力 性和经济性。设计要求达到换挡迅速、省力、方便、有较高的工作效率、工作噪 声低。因此变速器在汽车中得到广泛应用。 本次设计的是东风 EQ1090 载货型汽车变速器。 它的布置方案采用三轴式 5+1 挡和锁销式同步器换挡，并对倒挡齿轮和拨叉进行合理布置，其中一轴和第二轴 的轴线在同一直线上。这种布置形式缩短了变速器轴向尺寸，在保证挡数不变的 情况下，减少齿轮数目，从而使变
2、速器结构更加紧凑。 首先利用已知参数确定各挡传动比，然后确定齿轮的模数、压力角、齿宽等 参数。由中心矩确定箱体的长度、高度和中间轴及二轴的轴径，然后对中间轴和 各挡齿轮进行校核， 并利用 MATLAB 软件对中间轴的校核进行编程， 验证各部件选 取的可靠性。最后绘制装配图及零件图。 设计结论表明， 变速器齿轮及各轴尺寸确定， 各轴强度的校核满足设计要求， 设计结构合理。 关键词关键词：货车； 变速器；设计；同步器 II Abstract. Gearbox is the key part of the automobile. It is used to change the transmissi
3、on ratio, torque and running direction of the driving wheel. It can change the vehicle speed and tyre torque in a big scope, cut off the power transfer from the engine, and also provides a reverse traveling direction for the vehicle. Therefore, the reasonability of the structure design of a transmis
4、sion gearbox directly affects the vehicles dynamic performance. It is usually required shifting gears rapidly and conveniently, saving force, and having a higher working efficiency and low working noises. This thesis designed a manual transmission gearbox of theEQ1090ruck. A scheme of structure with
5、 three shafts, 5+1shifts and synchronizer adopted here, Combine to pour to block wheel gear and stir fork to carry on a reasonable decoration .where the first and second shafts were arranged in line. This kind of structure reduces the gearbox dimension in the axis direction, In assurance block to co
6、unt under the constant circumstance, decrease wheel gear number. therefore makes the designed transmission gearbox more compact. Using the given basic parameters, it was firstly determined the transmission ratio of each shift, the shaft center distances, the gear modulus, the gear pressing angles and widths, and so on. And then the general dimension of the gearbox, including its length, width and height. The stresses of the intermediate shaft and the gears were validated by using both the calcu
