| 摘要 |
PCT No. PCT/DE93/00275 Sec. 371 Date May 20, 1994 Sec. 102(e) Date May 20, 1994 PCT Filed Mar. 25, 1993 PCT Pub. No. WO93/19866 PCT Pub. Date Oct. 14, 1993.The invention relates to a drive for a press, in particular for a sheet metal forming press, the press including a press ram which can be moved up and down and a hydraulic movable counter support. The counter support can be moved in a forward stroke in the direction towards the press ram via at least one hydraulic cylinder by a first hydrostatic machine, and in a return stroke by the press ram. In known presses, during the return stroke of the counter support, the pressure medium is displaced from the hydraulic cylinder while a predetermined pressure is maintained by means of a pressure relief valve (pressure limiting valve) or a throttle valve (flow control valve). The balance sheet of energy of such a drive of such a press is to be improved. This is achieved by providing that the first hydrostatic machine is a pressure controlled machine, preferably an axial piston machine. Preferably, the axial piston machine can be swiveled in both directions, i.e. pivoted towards both sides. Further, at least during a portion of the return stroke of the counter support, pressure medium from the hydraulic cylinder flows across a second hydrostatic machine.
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