Patent ID: 8468866

Claim:
A die cushion device configured to generate press force to be applied to a slide member in a press machine, the die cushion device comprising: a cushion pad configured to receive force from the slide member; a support section supporting the cushion pad; a servomotor configured to raise and lower the support section for raising and lowering the cushion pad; a shock absorber device configured to relieve a shock between the cushion pad and the support section, the shock absorber device including a damping section configured to generate a reaction force in accordance with a relative speed of the cushion pad with respect to the support section, and an elastic section configured to generate a reaction force in accordance with a relative displacement of the cushion pad with respect to the support section; a first speed detector section configured to detect a speed of the slide member; a second speed detector section configured to detect a speed of the support section; and a controller section configured to control the servomotor so that a speed difference between the speed of the slide member and the speed of the support section is set to be a predetermined target speed difference value that changes over time, the predetermined target speed difference value being set so that a damping force by the damping section of the shock absorber device is equal to a difference between a target load of the cushion pad and a load generated by the reaction force by the elastic section of the shock absorber device when the cushion pad receives the force from the slide member.