Patent attributes
A die cushion controller, for driving a die cushion, disposed in opposition to a slide of a press machine, by controlling a servo motor, including: a pressure command portion which prepares a pressure command value for exerting a predetermined pressure to a press material disposed between the slide and the die cushion; a pressure detecting portion which detects an actual pressure exerted on the press material; a speed correction value preparing portion which prepares a speed correction value by multiplying a differential value of the pressure command value prepared by the pressure command portion by a coefficient; and a first speed command portion which prepares a speed command value to be instructed to the servo motor based on the pressure command value prepared by the pressure command portion, the actual pressure detected by the pressure detecting portion, and the speed correction value prepared by the speed correction value preparing portion.
