Patent ID: 6527540
Filing Date: 2003-03-04
Classification: B29C,F15B

Abstract:
A hydrostatic drive system for an injection molding machine which has a movable mold-closing plate (10), having a hydraulic cylinder (11) which has an annular, first pressure space (15) on one side of a piston (13), a piston-rod side, and a second pressure space (16) on an other side of the piston (13), a side remote from the piston rod, and via which the mold-closing plate (10) is movable in direction of a closing position by feeding of pressure medium into the second pressure space (16) and is moveable in direction of an open position by feeding of pressure medium into the first pressure space (15), and having a hydraulic pump (19), wherein pressure medium is deliverable by the hydraulic pump (19) into a pressure network (17, 24) having a hydraulic accumulator (24), and the first pressure space (15) of the hydraulic cylinder (11) is connected to the pressure network (17, 24), and the hydraulic cylinder (11) is controlled via a hydraulic transformer (18) which is located with its primary-side pressure connection (32, 44) at the pressure network (17, 24) and via the secondary-side pressure connection (32, 42) of which pressure medium is feedable to the second pressure space (16) of the hydraulic cylinder (11) or discharged from the second pressure space (16).