Hydraulic switching arrangement for supply of double acting hydraulic consumer has one proportional valve for two pilot inputs of each control valve in respective lines to consumer

摘要

The hydraulic switching arrangement for the supply of a double acting hydraulic consumer has first (2) and second (3) control valves in respective lines to the consumer with a single proportional valve (6,7) for the two pilot inputs (2a,2b,3a,3b) of each valve. A hydraulic logic circuit is located between the outputs of the proportional valves and the pilot inputs of the control valves. The hydraulic control inputs of reversing valves (4,5) are connected to the outputs of the proportional valves so that with a pilot pressure at the outputs of the proportional valves they are selectively connected to one of the pilot inputs of the control valves. The hydraulic logic circuit is designed so that the magnitude and/or time emergence of the control signals determines which pair of pilot inputs of the control valves are charged with pilot pressure.