System and method for controlling fuel vapor emmission in a small engine
AssigneeVaughn Kevin Mills
InventorVaughn Mills
Life of this patent
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Abstract
A small engine fuel system has a tank with an integrally formed filler tube having the lower end located at a level below the upper portion of the tank wall which is formed of vapor impermeable material which may include HDPE interspersed with EVOH or polyamide. In one exemplary embodiment the filler neck is disposed in a depression in the upper portion of the tank wall; and in another exemplary embodiment the filler tube has an insert which extends into the tank to a position below the upper portion of the tank wall to form a vapor space. The tank includes a fill limiting vapor vent/tipping valve with its outlet connected to a storage canister which outputs to the engine and which has an atmospheric air vent.
Claims17
A fuel vapor emission control system for a small engine comprising:
- (a) fuel tank with a fuel vapor impervious barrier in the wall thereof and having a portion of the upper wall forming a vapor dome;
- (b) a filler tube formed integrally with the wall structure of the tank with the end of the filler tube in the tank disposed at a level lower than the vapor dome such that during refueling fuel rises in said filler tube before the vapor dome.
- (c) an overfill limiting vapor vent/tipping valve with a vapor vent outlet disposed through the wall of said vapor dome;
- and
- (d) a conduit connecting said vapor vent outlet to the air inlet of the engine;
A method of controlling fuel vapor emission in a small engine fuel system comprising
- (a) forming a fuel tank wall structure with a vapor barrier therein and integral filler tube;
- (b) disposing the lower end of the filler tube at a predetermined level lower than the upper most portion of the tank wall structure;
- and,
- (c) disposing an overfill limiting vapor vent/tipping valve in the said uppermost portion of the tank wall structure;
- and,
- (d) connecting a vapor outlet of said valve to the air inlet of the engine;
- and,
- (e) limiting the filling level during refueling to the level of the lower end of said filler tube.
Dependencies are inferred from the claim text.