Patent ID: 6065386
Filing Date: 2000-05-23
Classification: F15B

Abstract:
Hydraulic device for controlling the pressure medium flow to and/or from a single-acting cylinder subjected to the influence of a load, with a pump that delivers pressure medium from a tank to the single-acting cylinder, and with a controlled valve array located between the pump and the single-acting cylinder, whereby said array, together with a controlled switching valve that returns pressure medium to the tank in one switch position, controls the pressure medium flow to and/or from the single-acting cylinder, characterized in thata series connection composed of a throttle (6) and a check valve (7) that prevents the reverse flow from single-acting cylinder (3) is located between the pump (1) and the single-acting cylinder (3) and bypasses the valve array (5),in that the switching valve (9; 19) in one position connects the line (8) between the throttle (6) and the check valve (7) with the tank (2) and in the other position interrupts the connection to the tank (2) andin that a pressure-compensating valve (10) keeps the pressure differential (.DELTA.P.sub.D1) across the throttle (6) constant and carries away the pressure medium volume that is not required to maintain the pressure differential (.DELTA.P.sub.D1) across the throttle (6).