Patent ID: 9688041
Date: 2017-06-27
CPC Classifications: B30B

Claim:
1. A drive device for a bending press with a press frame having a stationary press beam and a press beam which can be displaced relative to the stationary press beam via a beam adjusting device formed by a closed hydraulic system, the closed hydraulic system comprising: a hydraulic pump with a controllable drive motor, at least one control valve and at least one hydraulic linear actuator, the linear actuator comprising: wherein the piston working surface of the second piston in the other pressure chamber is oriented in opposite direction to the piston working surface of the first piston in the first pressure chamber, wherein the first piston arrangement and the second piston arrangement are connected to the displaceable press beam with piston rods and are therefore rigidly coupled with one another, wherein the cylinder chambers are disposed with mid-axes extending parallel with one another in an actuator housing provided in the form of a tandem cylinder, and wherein the first pressure chamber of the first cylinder chamber is connected to the other pressure chamber in the parallel other cylinder chamber via the control valve.