闭挤式精冲直齿轮模具结构优化设计

Optimization design of spur gear mold structure for closed-extruding fine blanking

针对闭挤式精冲模具型腔压力大的特点,提出了降低型腔压力的分流降压腔设计思路,并采取了分别在模具和坯料上设置分流降压腔的方案。以35钢直齿轮的闭挤式精冲为对象,采用Deform-3D有限元软件分别模拟了在坯料和凸模上设置半径为1~8 mm的分流降压腔,以研究其对型腔压力的调节作用以及其对零件成形质量的影响。分析表明,坯料上设置分流降压腔能更有效降低模具在径向和切向的受力,且分流降压腔半径不易过大,恰当的降压腔半径能减少齿形件齿顶开裂。此外,为减少干摩擦,提出了在模具相应位置设置润滑油存储结构。最后,设计了带有分流降压腔和润滑结构的实验模具,并通过实验检验了模具的实用性。

For the great pressure in the mold cavity of closed-extruding fine blanking, the idea of shunting decompression chamber to re- duce cavity pressure was proposed, and the shunt decompression chambers were set on blank and punch respectively. For the closed- extruding fine blanking of 35 steel spur gear, the shunt decompression chambers set with radius from 1 mm to 8 mm on punch and blank were simulated by finite element software Deform -3D to study the effects on cavity pressure adjustment and forming quality. The analysis results show that the shunt decompression chamber set on blank can reduce the radial and tangential stresses more efficiently, however, the appropriate radius of shunt decompression chamber can reduce crack at the top of gear. In addition, the setting of lubrication storage structure on relevant position of mold was also proposed in order to reduce dry friction. Finally, a mold with shunt decompression chamber and lubrication structure was designed. The utility of the mold was verified by experiments.