Patent attributes
A pressure regulating shut-off valve has a valve member regulating flow of fluid between an inlet and an outlet. The valve includes a pneumatic actuator having a piston having first and second faces that define first and second volumes within a cylinder. The second face has a greater surface area than the first face. The first and second volumes are fluidly connected to the inlet, and an electrically actuated valve controls the flow of fluid along a fluid path to the second volume. The electrically actuated valve closes the fluid path, when power is supplied to the electrically actuated valve, and opens the fluid path, when power is removed from the electrically actuated valve, which causes the pneumatic actuator to act on the valve member to hold the valve member in a fixed position.
