Hydraulic drive, in particular for machine tools, and method for controlling the hydraulic drive

A hydraulic drive, especially for a press, punching or nibbling machine, comprising:

• a double-acting work cylinder whose piston comprises a first working surface effective in the retracting direction and a second working surface effective in the extending direction, which each delimit one pressure chamber;
• at least two different pressures being applicable to at least one of the working surfaces by means of an actuator for retracting or extending the piston into and out of the work cylinder;
• an actuator unit which optionally enables a throttled return flow of hydraulic medium from the first pressure chamber delimited by the first working surface;
• wherein the drive comprises control means with which the actuator unit can be triggered in such a way prior to a sudden acceleration of the piston due to its sudden force release that there is a hydraulic damping of the movement of the piston as a result of an throttling of the return flow of hydraulic medium from the first pressure chamber which is caused by the actuator unit directly or indirectly;
• and
• wherein the actuator unit switches to the second pressure chamber delimited by the second working surface depending on the pressure rise so that the same causes a throttled return flow of hydraulic medium from the first pressure chamber delimited by the first working surface.