Patent ID: 8079567

Claim:
A valve assembly comprising: a valve body that has an inlet section for coupling to a container for a fluid under pressure and an outlet for coupling to a piping system, a piston movable within the valve body along a first axis between an open position allowing fluid communication between the inlet section and the outlet, and a closed position blocking said fluid communication, the piston having an end section, a sealing section and a middle section located between the end section and the sealing section, a cavity extending along the first axis and configured to receive the piston within the valve body, the cavity has a superior chamber between the end section and the middle section, an intermediate chamber between the middle section and the sealing section, and an inferior chamber between a wall of the cavity and the sealing section, wherein the piston is configured to prevent an exchange of fluid between the chambers, a spring located within the superior chamber and configured to exert a spring force onto the piston to urge the piston towards the open position, and an actuator device coupled to the valve body and configured to provide upon actuation for a first flow of fluid outside the cavity from the inlet section to the superior chamber, the first flow causing a pressure within the superior chamber to increase until it is about the same as the pressure within the container so that the spring force moves the piston to the open position, wherein in the open position a main flow of fluid flows from the inlet section via the intermediate chamber to the outlet.