普通冲孔与无飞边精密冲孔的瞬时间隙及对冲孔质量的影响

提出了瞬时间隙的概念 ,研究了瞬时间隙对冲孔剪口质量的影响 ,对普通冲孔工艺与精密无飞边冲孔工艺凸、凹模间的瞬时间隙进行了对比分析 ,认为普通冲孔时瞬时间隙不定常是造成剪口质量差的根本原因 ,而无飞边精密冲孔时凸、凹模间为负间隙 ,其瞬时间隙保持定常 ,因此可使剪口光洁剪切带长度提高 1.5倍 ,且冲制的孔无纵向飞边

Instantaneous Clearance of Ordinary Punching and Precise Punching Without Burr and Its Influence on Punching Quality

The concept of instantaneous clearance is put forward, and its influence on the quality of shearing fracture is stu died. The instantaneous clearances between the male die and female die during ordinary punching and precise punching without burr are contrastively analyzed. It is considered that the basic reason causing the bad quality of shearing fracture is the instable instantaneous clearance in the ordinary punching process. While precise punching without burr, the clearance between the male and female die is negative and the instantaneous clearance is stable, so that the length of bright shearing fracture can be raised to 1.5 times and workpieces without longitudinal burr can be obtained.