METHOD FOR CONTROLLING BLANKING IN HYDRAURIC PRESSURE PRESS

摘要

PURPOSE:To smooth blanking and to prevent slug rise by blanking a blank material while applying oscillatory pressing force to a punch which makes stroke motion. CONSTITUTION:A setting part 11 sets a pitch and high and low speeds in such a way that a punch 4 makes the fast and slow stroke motion at an adequate stroke pitch, i.e., oscillatory stroke motion during the time since just before the contact of the punch 4 with a blank material W until the punch starts an ascending stroke after blanking said material and detaches from the material W in said stroke. The stroke speed of the punch is finely and optionally expressed by the degrees of opening and closing of valves 10b-10f in a servocontrol valve 10.