变薄拉深模具的改良设计

因设计安装在第四步工序的变薄拉深模具失效（主要表现在凸模应力集中处断裂、触点保护开关无法检测），造成模具及传送机械手严重损坏。通过对模具结构的分析，提出了将凸模加工成整体、应力集中处在距离拉深零件稍高地方的改良方案。改良后的模具效果明显，不但改变了凸模的断裂位置，还由于加大了应力集中处的截面积，增加了抵抗各种应力的强度，提高了凸模的使用寿命。拉深次数从原来的四、五十万次提高到二、三百万次，同时也减少了关联工序的模具损坏。

Improved design of the thinning drawing die

Since thinning drawing die designed and installed in the forth stage is malfunctio- ning, which mainly manifests in punch rupture at stress concentration place and contact pro- tection unable to be detected, die and transmission manipulator were badly damaged. According to die structure analysis, an optimized plan in which punch was made as an entirety and stress concentration occurred at somewhere higher away from drawing parts was proposed. The optimized die works quite well. Not only the punch rupture location was changed, but also the stress concentration cross sectional area was increased. Thus, the strength to resist kinds of stress and punch lifetime were improved. Drawing times was increased from original forty or fifty thousand times to two or three million times. Die da- mage in associated process was reduced at the same time.