Abstract: A vapor vent/tipping valve has a diaphragm with a bleed therethrough responsive to the differential pressure of bleed flow to control vapor venting to the canister and vapor recirculation to the filler tube. A dip tube causes rising fuel in the tank to close the dip tube and prevent vapor flow to the diaphragm bleed thereby starving the recirculation line and allowing nozzle discharge to create a vacuum in the filler and effect nozzle shutoff. Alternatively, float operated shutoff valves may be employed in the dip tube and vapor vent chamber inlet. the shutoff valves may include inertial members for closing the float valves to afford tipping/rollover protection.

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 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.