Two-stage ORVR control valve
AssigneeG.T. Products, Inc.
InventorsRobert P. Benjey, Rudolph Bergsma
Life of this patent
Estimating the term…
Abstract
An onboard vapor recovery system for a vehicle fuel system having a fuel tank, a filler neck dynamically sealed by high pressure fuel flow from a filler nozzle, and a vapor recovery apparatus such as a carbon canister. The system includes a liquid level operated control valve which shuts off refueling with a two-stage closing operation providing an initial soft shutoff and a final shutoff. The system also preferably includes a valve in the fuel tank to maintain a predetermined pressure head sufficient to hold the system closed against further refueling at least temporarily, and a positive action, one-way check valve in the lower end of the filler pipe to prevent spitback of fuel from the pressurized tank once refueling has ceased.
Claims4
A fuel level responsive control valve for controlling the venting of fuel vapor from a vehicle fuel tank to a vapor recovery apparatus in a manner providing a shutoff cue to a person filling the tank, the control valve comprising:
- a valve adapted for venting fuel vapor from the tank to the vapor recovery apparatus at a first higher rate when the fuel level is below a first level, at a second lower rate when the fuel level reaches the first level, and for closing when a second higher level is reached, the valve comprising two stage coaxial valve means responsive to the level of liquid fuel in the tank, the coaxial valve means comprising a liquid level responsive float, first and second valves associated with the float, and a vent outlet, the float being responsive to liquid fuel reaching the first level to force the first valve to a position partially closing the vent outlet, the first valve being yieldably biased from the second valve, the float being responsive to liquid fuel level above the first level to force the second valve against the bias of the first valve to fully close the vent outlet.
A fuel level responsive control valve for controlling the venting of fuel vapor from a vehicle fuel tank to a vapor recovery apparatus in a manner providing a shutoff cue to a person filling the tank, the control valve comprising:
- a valve adapted for venting fuel vapor from the tank to the vapor recovery apparatus at a first higher rate when the fuel level is below a first level, at a second lower rate when the fuel level reaches the first level, and for closing when a second higher level is reached, the valve comprising a liquid level responsive float, first, and second valves associated with the float, and a vent outlet, the first valve comprising a primary valve cage and a primary valve element axially moveable within the primary valve cage, the primary valve element adapted to sealingly engage the vent outlet and, a vent passageway in the primary valve element for permitting reduced venting from the fuel tank through the primary valve element and the vent outlet when the primary valve element is sealingly engaged with the vent outlet, the first valve further including a spring in the primary valve cage for biasing the primary valve element upwardly;
- the second valve comprising a secondary valve element inside the primary valve cage, located coaxially with respect to and below the vent passageway in the primary valve element such that the secondary valve element closes the vent passageway when the primary valve element is forced downwardly against the spring in the primary valve cage.
A fuel level responsive control valve for controlling the venting of fuel vapor from a vehicle fuel tank to a vapor recovery apparatus in a manner providing a shutoff cue to a person filling the tank, the control valve comprising:
- a control valve having a valve body adapted to be mounted in the fuel tank, the control valve having a hollow valve body portion containing a float mounted for movement within the hollow valve body portion toward and away from a first vent outlet in response to liquid fuel level, and coaxially offset primary and secondary valve elements connected to the float, the primary valve element being located above the secondary valve element and including a secondary vent outlet, the primary valve element further being yieldably biased away from the secondary valve element, such that when the float is moved toward the first vent outlet by rising liquid fuel level to a first position the primary valve element closes against the first vent outlet but remains yieldably biased away from the secondary valve element such that the secondary vent outlet in the primary valve element is open for reduced volume venting through the first vent outlet, and the float in a second position at a second higher fuel level forces the secondary valve element against the bias of the first valve element to a position closing the secondary vent outlet to close venting through the first vent outlet and therefore through the control valve.
Dependencies are inferred from the claim text.