Patent ID: 7581487

Claim:
A pressure-compensating directional control valve for actuating hydraulic actuators, comprising: at least one modular valve body having at least one through receptacle for at least one bidirectionally slidable shuttle, at least one driving fluid delivery port connected to a pump, at least one discharge port for the fluid, at least one first output opening and a second output opening, said first and second output opening connected respectively to a first chamber and to a second chamber of a hydraulic actuator, said shuttle being remotely controlled by remote operation means and being adapted to selectively connect said delivery port to said first output opening and said discharge port to said second output opening and vice versa; at least one bridge provided in said valve body for selective communication, by way of said shuttle, of said delivery port with said first chamber or with said second chamber of the actuator, for actuation thereof in one direction or the other; at least one unidirectional hydrostat, which is connected to said at least one bridge by way of a supply duct and is adapted to draw selectively a pressure signal of a load of the actuator, said signal being suitable to adjust selectively a delivery pressure of the pump so as to keep substantially constant the pressure drop between said delivery port and the actuator in any load condition; at least one actuation head connected with said modular valve body and comprising at least one main hydrostat, which is adapted to connect selectively, under the action of at least one contrast spring thereof and of said load pressure signal, the delivery duct of the pump to a discharge, so as to adjust said delivery pressure to a suitable value, which is preset according to said load; at least one slide valve, provided in said at least one actuation head for connecting selectively to said discharge said load pressure signal; at least one line for driving said at least one slide valve that passes through said modular valve body and is connected to said discharge, so as to provide a controlled decompression of said load pressure signal; a pair of holes provided in said modular valve body and which are adapted to connect, by way of respective diameter expansions of said at least one through receptacle and a groove of said at least one shuttle, said discharge to said slide valve of said actuation head, so as to drive a decompression of said signal.