Patent ID: 7597306

Claim:
A directional control seat valve comprising: a piston that is biased against a valve seat, whereby a connection between an inlet port and an outlet port may be controlled open; and a compensation piston associated with the piston, an end face of the compensation piston that delimits a pressure chamber being subjected to a same pressure as at one of the ports, wherein the compensation piston is arranged before the valve seat, when viewed in a closing direction, so that the end face thereof and a range of the piston seated on the valve seat are arranged on one side relative to the valve seat, an external diameter of the end face, with which the compensating piston delimits the pressure chamber, is smaller than a valve seat diameter; and an actuation projection being arranged on an other side of the valve seat opposite to the compensation piston, the actuation projection having an end face attached directly or indirectly to an actuator that moves the actuation projection, the end face of the actuation projection positioned being outside of the pressure chamber, and the end face of the actuation projection being sealed from the pressure at the inlet and outlet ports.