Abstract: In a forming machine of the hydraulic press or forging machine type having at least one press cylinder acted on by a pair of values of stroke frequency and stroke volume predetermined by a first piston pump, the stroke frequency and stroke volume of the press cylinder can be adapted to the working requirements from cogging to planishing if the press cylinder has associated with it a second piston pump in parallel with the first piston pump and having a second pair of values of stroke frequency and stroke volume different from the first pair of values, and if the two piston pumps can be switched to connect them to the press cylinder simultaneously or alternatively.

Abstract: A method of controlling the drive of a forming machine, in particular of a hydraulic press or hydraulically driven forging machine, having at least one pump cylinder actuated by a crank-type driving mechanism and having return cylinders subjected to constantly rechargeable accumulator pressure, makes simple stroke position shifting and longer overall strokes possible by shutting off the supply of pressure medium to the return cylinders after a working stroke, whereby the return stroke is prevented from occurring and pressure fluid is sucked from the low pressure container into the working cylinder of the forming machine, and only turning the supply of pressure medium to the return cylinders on again for a new working stroke.