Abstract: An on-board refueling vapor recovery system includes a shutoff mechanism that closes a first vapor path between the fuel tank and the filler cup when liquid fuel in the tank reaches a predetermined level and a vent line closure that closes a second vapor path between the canister and the filler cup, wherein closure of the first vapor path and the second vapor path reduces pressure in the filler cup to induce shutoff of a fuel nozzle.

Abstract: A double shut-off refueling valve responds to a full fuel tank level by closing the recirculation line and the canister line. The valve includes at least one float having one or more sealing surfaces corresponding with the recirculation line and the canister line, respectively. The sealing surface is on the top of a float in the float valve. When the fuel in the tank reaches a full level, the float moves upward to close the recirculation line and the canister line substantially simultaneously. In one embodiment, the valve is a float valve having a coaxial seal where the two valve openings corresponding to the recirculation line and the canister line are arranged concentrically. In other embodiments, the sealing surfaces can be, for example, a ribbon seal, two separate sealing surfaces, or any other seal configuration that corresponds with the orientation of the recirculation line and the canister line within the fuel system.

Abstract: A filler tube assembly for use in a system having vapor recirculation includes a check valve having a flapper that is responsive to the viscosity of fluid around the flapper and/or a differential pressure across the flapper. The assembly also includes a nozzle chamber formed in the filler neck that has a constant diameter to ensure consistent vacuum generation regardless of fuel nozzle length.

Abstract: A valve has a flexible flap with a neck that engages with a slot on a spud to close a passage in the spud. When an object is inserted into the passage, the flap bends to an open position to allow flow through the passage. When the object is removed from the passage, the resiliency of the flap causes the flap to return to the closed position without any external biasing device. The flexibility of the flap material eliminates the need for a separate hinge mechanism or flap biasing mechanism in the valve.

Abstract: A method of mechanical twist lock attachment of a vent valve or fitting over an aperture in a plastic fuel tank having an embedded vapor barrier layer. A ring having circumferentially spaced internal lugs is secured to the tank by weldment around an aperture in the tank wall exposing an edge of the barrier layer. A seal ring on the vent valve is located in the aperture to seal the exposed vapor barrier edge. Outwardly extending projections on the vent valve attach the vent valve by twist locking engagement with the projections on the ring.

Abstract: A cover for a filler neck includes a body portion and a movable protective door that covers and exposes an opening in the filler neck. The protective door includes a ledge that protrudes from the plane of the door so that the door can be easily moved to an open position by pressing a tip of a fuel nozzle against the door. The door itself may be biased to move into a closed position automatically when the fuel nozzle is removed from the ledge.

Abstract: A capless seal door for a fuel tank filler tube employs a door valve with a flexible annular seal which, upon closing against a seat on the undersurface of a nozzle-receiving orifice formed in a bulkhead across the tube, initially wipes on the seat and is subsequently compressed thereon.

Abstract: Isolation valves of the invention are advantageously mechanically actuated. Such valves and associated methods comprise a first port in fluid communication with a first component; a second port in fluid communication with a second component; a third port in fluid communication with a third component; a diaphragm disposed within the valve for closing a normally open internal pathway to occlude fluid communication between the first port and the second port in response to a pressure differential across the diaphragm; and a flow sensitive pressure device for controlling the pressure differential across the diaphragm. Fluid flows from the second component to the third component upon closing of the normally open internal pathway. In an exemplary embodiment, isolation valves and methods of the invention are adapted for use in fuel tank emission control systems.

Abstract: A check valve for connection in a fuel tank filler tube. The valve has a tubular body with a plurality of radially inwardly extending projections on the inner surface of the tubular body or mounting adaptor. A valve seat is disposed downstream of the ribs, and an aperture is formed in the side of the tubular body. When the end of a siphoning hose is inserted into the check valve, the projections deflect the hose through the aperture to facilitate further insertion of the hose into the tank.

Abstract: A pass-through formed of material unweldable to a non-metallic tank has an adaptor ring formed of material also unweldable to the tank which is welded to the pass-through body. Prior to welding the adaptor ring to the pass-through the adaptor ring is chemically bonded to a mounting ring, which is formed of material weldable to the tank. The assembly thus formed may then be welded to the tank.

Abstract: A fuel filler tube assembly including a one-way valve or check valve. The tube assembly is adaptable for pre-assembly on either a metal or plastic fuel tank and employs a common check valve with an adapter tube for plastic tanks. The valve employs a flapper with spaced ribs for deflecting a siphon hose away from the valve seal; and, the ribs are spaced to maintain the flow stream of he fuel during refueling and facilitating opening of the flapper.

Abstract: A fuel tank filler tube has a seal disposed therein for sealing about a refueling nozzle upon insertion in the tube. When the tank is filled and fuel backs up in the filler tube, in the event of failure of the automatic nozzle shutoff, an annular pressure relief valve surrounding the seal opens and provides for by-pass flow around the seal to the upper end of the filler tube. The annular valve includes a rigid ring member with an annular flexible seal attached and is spring biased to the normally closed position.

Abstract: A method of mechanical twist lock attachment of a pass-through valve or fitting over an aperture in a plastic fuel tank having an embedded vapor barrier layer. A ring having circumferentially spaced internal lugs is secured to the tank by weldment around an aperture in the tank wall exposing an edge of the barrier layer. A seal ring on the pass-through is located in the aperture to seal the exposed vapor barrier edge. Outwardly extending projections on the pass-through attach the pass-through by twist locking engagement with the projections on the ring.

Abstract: A two-stage pressure differential pressure responsive flow control valve is disposed to provide greater fuel vapor recirculation to a tank filler tube when high vacuum conditions are encountered during refueling from a fuel dispensing nozzle inserted in the filler tube. The pressure responsive valve has an obturator with a passage therethrough for providing a relatively low flow rate when the valve is in the closed condition resulting from a relatively low vacuum during refueling. When a higher vacuum is encountered, the obturator is moved to the open position permitting greater flow. Preferably, the pressure responsive valve is disposed in a common housing with a float operated rollover valve.