Hydraulic three-chamber system separating device, has control pistons pushed by force of over-lifting spring or movable back and forth based on reduced pressure differences during flow-through and idle position

摘要

The device has an unloading valve (68) for emptying a middle zone (20) and actuated by pressure difference between forward- and rear pressures (P1, P2). Control pistons (48, 58) are connected with each other by a piston rod (60) that is guided through the middle zone. Forward- and rear pressure-sided cylinders (47, 57) are rigidly connected with each other by piston rod. The pistons are pushed by force of a over-lifting spring (67) or movable back and forth based on small pressure differences during a flow-through and idle position.