スライドモーション制御による角筒インパクト成形の高精度化

抄録

Slide motion control for a servo press was investigated with the aim of improving shape accuracy in square cups formed by impact extrusion. We studied the effects of slide speed on wall thickness accuracy in the product. We explored the factors in defective product formation by analyzing strain curves during the punching operation. The results clarified that elastic deformation of the punch in the bending direction during the initial working portion of the stroke affects the accuracy of wall thickness. When observing the process using a high-speed camera, we deduced that unstable movement of the slug when initially impacted by the punch caused the punch to deform elastically in the bending direction. By employing pulse motion during the initial stage, whereby the punch is repeatedly advanced and retracted until the slug fills the die, elastic deformation of the punch in the bending direction could be reduced, improving the wall thickness accuracy in the product.