| 摘要 |
PROBLEM TO BE SOLVED: To provide a forming ram elevation method and a punch press improved in a forming edge precision without reducing a working speed. SOLUTION: When forming is conducted to a work W by striking a punch P with a ram 15 in cooperation with a die D, an elevation control means 39 elevates and lowers the ram 15 by an elevating means 17 in accordance with a working pattern stored in a working pattern memory part 43. That is, when working is started from the upper dead center position of the ram 15, the ram 15 is first stopped at its ascending end for a prescribed time, is descended down to a descending end, is stopped for a prescribed time and is ascended up to an ascending end after forming, so overshoot is reduced. Further the ram 15 is always descended from the ascending end position in working, so an overshoot quantity is made constant.
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