Patent ID: 7219593

Claim:
A saturation-proof hydraulic control device, comprising: two or more elements, each element comprising a proportional six-way, threeposition spool ( 4 ), a proportional pressure compensator ( 3 ) with a spring side, notches on the spool ( 4 ), the notches operative for a correct operation, and a pressure selector means (MS) operatively connected to the spring side of the pressure compensator so that a higher-pressure work function sends a pressure to the spring side of the pressure compensator ( 3 ) for operation as a check valve, the pressure selector means comprising a selector valve ( 7 ) with a ball ( 7 a ), a check valve ( 6 ) with a ball ( 6 b ), a pusher ( 9 ) connected with the ball ( 7 a ) of the selector valve ( 7 ), and a spring (M 7 ) acting on the ball ( 7 a ) of the selector valve ( 7 ), wherein, the ball ( 6 b ), in a working condition, is kept mechanically open by a mechanical transmission of the pusher ( 9 ) connected with ball ( 7 a ) of selector valve ( 7 ), with the spring (M 7 ) acting on the ball ( 7 a ) of the selector valve ( 7 ), and with the spring (M 7 ) generating a minimum load slightly greater than a pressure drop of a maximum flow-rate through the pressure compensator ( 3 ), so that the higher-pressure work function sends a pressure existing between the spool ( 4 ) and the pressure compensator ( 3 ) to the compensator ( 3 ) of another element and to a pump (P).