Press working method for plate material and press working apparatus using the same

摘要

According to the present invention, in a press die unit for performing a plurality of pressing steps on a strip-like plate material, there are provided a pair of stationary dies and a pair of movable dies. In each pair of dies, a plurality of punches and dies are equipped, and at least a part of punches or dies are lowered or lifted in a manner to be used or not used. By combining the positional adjustment of the movable dies and the increase or decrease in the number of the punches and dies for performing the press working process, a plurality of pressing steps for a pressed product are completed with a single pressing die unit even when the length of the pressed product is changed to a various kind.