Vent valve for fuel tanks and the like
AssigneeKaman Aerospace Corporation
InventorBenjamin S. Liff
Life of this patent
Estimating the term…
Abstract
A vent valve for venting fuel and other such tanks includes a float having a valve closure poppet for opening and closing the valve at a predetermined liquid level in the tank. The valve also has a bellows actuator which relieves excessive internal tank pressures by holding the closure poppet open in opposition to buoyant forces on the float when the excessive pressures are encountered. The bellows actuator and the valve poppet are self-compensating since higher internal tank pressures cause the actuator to increase the valve opening for greater pressure relief.
Claims16
A vent valve for a fuel tank and the like for performing both venting and pressure relieving functions comprising:
- a valve housing defining inlet and exit openings in fluid communication through an internal fluid passageway for venting fluids in a tank through the passageway from the inlet opening to the exit opening;
- movable closure means associated with the valve housing for closing the fluid passageway and preventing fluid flow through the valve housing between the inlet and exit openings, the closure means including a float having a substantially fixed buoyancy and movable relative to the valve housing by buoyant forces of liquid in the tank, the float having upper and lower positions established by the liquid level in the tank and in the upper position causing the closure means to close the fluid passageway and the tank, and in the lower position causing the closure means to open the fluid passageway and freely vent the tank;
- and
- pressure responsive actuating means responsive to the pressure in the tank above the liquid in both the open and closed positions of the passageway and operatively associated with the movable closure means at the upper position of the float for opposing closure of the fluid paassageway by the float at tank pressures above a preselected level and depressing the float from the upper position in opposition to the buoyant forces of the liquid to open the fluid passageway and relieve pressures within the tank.
In a tank receiving and dispensing a liquid and having a limited capacity, an integrated vent and pressure relief valve comprising:
- a fluid conduit having a first end within the tank, a second end outside of the tank and a fluid passageway between the first and second ends for passage of fluids between the interior and exterior of the tank;
- closure means including a float responsive to the liquid level within the tank and having a closure element movable from a first position in which the passageway in the fluid conduit is open and a second position in which the passageway is closed, the element being urged to move from the first to the second position to close the passageway by buoyant forces of the float in the tank as the liquid approaches a predetermined level;
- and
- pressure relief means responsive to pressure within the tank and operatively associated with the closure means for displacing the closure element from the second position and opening the fluid passageway in opposition to the buoyant forces of the float in liquid levels in the tank at or above the predetermined level and at internal tank pressures above a selected level.
Dependencies are inferred from the claim text.