Patent ID: 7210501

Claim:
A valve for controlling a pressurized fluid, comprising: a valve body including a fluid inlet port, at least one fluid discharge port and a flow passage in communication with both the inlet port and the discharge port, the flow passage defining first and second annular seating points axially spaced on a longitudinal axis of the flow passage, the first seating point having a first sealing diameter and the second seating point having a second sealing diameter smaller than the first sealing diameter; a valve member having first and second valve portions being slidably positionable within the flow passage, the first valve portion having a first portion diameter defining a first portion area and the second valve portion having a second portion diameter defining a second portion area smaller than the first portion area; a seating portion of the valve member positionable to abut the first seating point in a first position and to abut the second seating point in a second position, wherein a fluid exposed area of the seating portion is defined where the valve member is in the second position; wherein the valve member is movable from the first position to the second position by a driving force applied in a first direction and in the second position the pressurized fluid acting on both the first portion area and the fluid exposed area creates a net return force operable to direct the valve member in a second direction opposite to the first direction upon cessation of the driving force.