초록 ▼

A vapor handling system is provided to control fuel vapor in a vehicle fuel system to prevent the fuel vapor from escaping to the atmosphere during filling of the vehicle fuel tank. An on-board vacuum-actuated system is included for preventing overfilling of the tank by automatically triggering shut

A vapor handling system is provided to control fuel vapor in a vehicle fuel system to prevent the fuel vapor from escaping to the atmosphere during filling of the vehicle fuel tank. An on-board vacuum-actuated system is included for preventing overfilling of the tank by automatically triggering shut-off of fuel flow from a fuel-dispensing nozzle when the fuel tank is full. A control valve system is also included for protecting the canister from exposure to liquid fuel during an overfill condition which may be caused by a malfunction of a fuel-dispensing nozzle.

대표청구항 ▼

A system for recovering fuel vapors from a vehicle system during refueling, the vehicle fuel system including a fuel tank and canister means for processing fuel vapor, the system comprising delivery means for conducting fuel vapor between the fuel tank and tne canister means, valve means for selecti

A system for recovering fuel vapors from a vehicle system during refueling, the vehicle fuel system including a fuel tank and canister means for processing fuel vapor, the system comprising delivery means for conducting fuel vapor between the fuel tank and tne canister means, valve means for selectively blocking flow of fuel vapor through the delivery means, the valve means being movable between a flow-blocking position and flow-delivery positions, passageway means for communicating a closing pressure from the fuel tank to the valve means to move the valve means to its flow-blocking position, an actuation means for selectively venting the passageway means to the atmosphere to dissipate any closing pressure therein to permit pressure generated by fuel vapor in the fuel tank having a magnitude in excess of a predetermined threshold level and communicated to the valve means via the delivery means to apply a load to the valve means sufficient to move the valve means from its flow-blocking position to a flow-delivery position, thereby permitting pressurized fuel vapor to flow from the fuel tank to the canister means through the delivery means, the valve seat engaging the first surface upon closure of the valve means to its flow-blocking position to define a third effective area outside the venting area exposed to pressure communicated from the canister means via the delivery means, the first and second effective areas cooperating to provide vacuum relief means for generating a movement-inducing load on the first surface that is relatively larger than any movement-inducing load on the second surface in response to conmunication of a predetermined negative pressure to both of the first and second effective areas and exposure of the third effective area to another pressure having a magnitude that is greater than the magnitude of the predetermined negative pressure so that the vent valve is moved is moved from a flow-blocking position against the valve seat to a flow-admitting position away from the valve seat, whereby suction within the fuel tank draws air and fuel vapor in the canister means into the fuel tank.