汽车变速器输入轴塑性成形工艺

Forming technique for the input shaft of a vehicle gearbox

输入轴是汽车变速器中重要零件,针对其特殊结构提出一火加热和轧锻结合的塑性复合加工工艺,即采用圆柱坯料只进行一次加热,依次采用楔横轧和锻造工艺加工塑性成形输入轴.本文分别设计楔横轧和锻造模具,并进行相关实验.在锻造工艺中轴部圆角采用挤压方案成形,避免其出现折叠缺陷.阶梯轴作为两步工艺的中间产品,其在复合工艺过程中起到承上启下的作用,分别对阶梯轴锥角和轴长进行实验与分析,确定参数的最佳选取范围,并最终通过复合工艺加工成形输入轴.输入轴齿形填充饱满,各部分无缺陷.

The input shaft is an important part in a vehicle gearbox. A novel compound forming technique was designed due to the special structure of an input shaft. This forming technique is named once heating and combining rolling with forging,meaning that the cylindrical billet is first heated,rolled by cross wedge rolling and forged sequentially. The input shaft was deformed by the novel technique combining cross wedge rolling with die forging. The dies of cross wedge rolling and forging were designed in this paper,and the accuracy of finite element simulation was determined compared to experimental data. A great agreement between simulated and experimental results validates the predictability of finite element simulation. Extrusion was used to form the axis fillet in the forging process to avoid folding defects. The multidiameter semi-manufacture is both the product of cross wedge rolling and the billet of die forging,so it plays an important role in the whole process. The effect of cone angle and diameter was researched by experiments to determine the optimum values of parameters. Finally,the input shaft with full teeth and no defect was formed by the novel forming technique.