链轮闭式模锻成形模具齿形型腔精确设计方法

Precision Design Method of Tooth Cavity of Chain Wheel Flashless Die Forging

链轮是最基本的机械零件之一,在链传动装置中起着传递动力及运动的作用。目前链轮的齿廓多采用锻坯切削方式加工,存在切削余量大、材料利用率低、生产效率低及力学性能下降等问题。提出采用闭式模锻工艺直接成形链轮齿形,以实现锻件齿廓不再切削加工而直接达到链轮产品对齿廓尺寸的精度要求;考虑影响锻件尺寸的若干因素,给出了链轮闭式模锻成形模具齿形型腔精确设计方法。采用齿廓型腔尺寸精确设计的成形模具进行了某型号链轮闭式模锻成形实验,并与常规设计进行了对比。结果表明,所建立的链轮闭式模锻成形模具齿形型腔精确设计方法具有较高的准确性,能够实现链轮齿形不再加工的模锻成形精度要求。本文中建立的齿廓型腔尺寸精确设计方法可为其他齿类锻件精密模锻模具齿廓型腔的精确设计提供参考。

As one of the most basic mechanical parts,a chain wheel plays the role of transmitting power and motion in the chain transmission device.At present,tooth profile of the chain wheel is mostly machined by cutting the forging blank,which comes along with many problems such as large cutting allowance,low material utilization rate,low production efficiency and decreased mechanical properties.A flashless die forging process is proposed to form the tooth profile of the chain wheel.In order to meet the precision requirements of chain wheel tooth profile without cutting machining and considering the influence factors for the forgings size after forged,a precise design method of tooth cavity of the chain-wheel flashless die forging is presented.An experiment of flashless die forging for a chain wheel is carried out by using the die with precise design method of tooth profile cavity established and compared with the conventional design.The results show that the precision design method of chain wheel tooth cavity for flashless die forging has high accuracy,and can directly meet the requirements of chain wheel tooth machining precision.The precise design method of tooth profile cavity size established in this paper can provide reference for other gear forgings.