초록 ▼

A tank vapor vent valve assembly uses a spring loaded sealing flapper door located below a normally open float chamber. The flapper door spring is specifically designed to open when the tank pressure falls, allowing make up air to pull the flapper door down and draw in make up air through the canist

A tank vapor vent valve assembly uses a spring loaded sealing flapper door located below a normally open float chamber. The flapper door spring is specifically designed to open when the tank pressure falls, allowing make up air to pull the flapper door down and draw in make up air through the canister inlet.

대표청구항 ▼

A vapor vent valve assembly for a vehicle of the type that has a vapor storage canister with an outside air inlet and a fuel- tank with a filler pipe that is normally closed and is adapted to receive a fuel nozzle when open, and in which said fuel tank is subject to negative and positive pressure fl

A vapor vent valve assembly for a vehicle of the type that has a vapor storage canister with an outside air inlet and a fuel- tank with a filler pipe that is normally closed and is adapted to receive a fuel nozzle when open, and in which said fuel tank is subject to negative and positive pressure fluctuations when said filler pipe is closed, said vapor vent valve assembly comprising, a downwardly opening sealing flapper door that is normally biased upwardly and closed with a predetermined pressure less than said fuel tank negative pressure fluctuation, but which is adapted to be opened by said fuel nozzle, a float chamber having an open fitting at the top thereof, a vapor vent line running from said fitting to said canister, an overfill prevention float contained within said float chamber which is normally located below said fitting, and, a passage running from a location within said filler pipe above said flapper door into said float chamber, whereby, when said filler pipe is opened and said nozzle inserted to open said flapper door, fuel vapors displaced from said fuel tank may flow freely from said filler pipe to said canister, and when said nozzle is removed and said filler pipe is closed, fuel vapors forced up said filler pipe by a positive fuel tank pressure fluctuation will be prevented from escaping by said normally closed flapper door, while a negative fuel tank pressure fluctuation will pull said flapper door down and open to draw outside air through said canister inlet to relieve said negative tank pressure.