Abstract: A valve assembly is disclosed for controlling fluid flow between two reservoirs. The valve assembly includes a relief valve arranged inside the housing and configured to open a first fluid flow path when the first reservoir is above a first predetermined pressure value.

Abstract: A fuel vapor emission system for small engine gas tank which does not require redesign or retooling for manufacturing of the tank. A new filler tube has the lower end positioned to cause fuel to rise rapidly in the tube before the tank is full, signaling the operator to stop refueling and maintain a vapor dome in the tank when the filler cap is replaced. A vapor vent valve is disposed in a separate access opening and includes a float operated rollover valve. The vent valve opens when a predetermined positive pressure is reached in the tank; and, a reverse flow vacuum relief valve is disposed in the vent valve. The outlet of the vent valve is intended to be connected to either a storage canister or the engine air inlet.

Abstract: A fuel tank assembly for small engines having a vapor storage canister disposed within the tank in the vapor dome with an atmospheric vent line to the canister through the tank wall and a canister vapor outlet line also through the tank wall. A liquid/vapor discriminator is disposed in the vapor dome of the tank with the discriminator outlet connected to the canister inlet. A fuel filler tube extends through the tank wall to a desired depth to prevent vapor from escaping through the filler tube when the fuel level rises to the lower end of the filler tube and alerts the operator by rapid rise of fuel in the filler tube.

Abstract: A fuel tank cap including a vapor storage receptacle and a means for protecting the vapor storage receptacle from liquid and absorbent granulated carbonaceous material. A fuel storage system including a fuel tank cap having a vapor storage receptacle is also disclosed.

Abstract: A valve is disposed between a fuel tank and an engine intake manifold in a small engine fuel system equipped to recapture running loss evaporative emissions. The valve includes a resilient diaphragm that blocks the flow path When vapor pressure in the fuel tank reaches a predetermined level, the diaphragm opens and allows the vacuum forces in the manifold to purge the vapors in the fuel tank by drawing the vapors into the manifold to be burned in the engine. The diaphragm isolates the fuel tank vapor dome from the vacuum pressure generated in the manifold, thereby preventing the engine from being starved of fuel. The valve may be integrated with a liquid discriminating valve to form a valve assembly.

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.

Abstract: A compact overflow limiting vapor vent/tipping valve assembly with pressure and vacuum relief. A float operated vapor vent/tipping valve may be either attached to a cap with a vapor outlet port which is welded over an access opening in the tank or, the valve may have a valve body formed integrally as one piece with a portion of the tank wall structure. The vapor vent/tipping valve includes therein a gravity operated pressure relief valve for preventing vapor venting below a threshold pressure; and, the pressure relief valve includes a vacuum relief valve permitting reverse flow to admit make up air in the event of sub-atmospheric pressure in the fuel tank.

Abstract: A combination vapor vent/rollover valve and surrounding storage canister are disposed in a common housing for positioning inside a small engine fuel tank. In one embodiment described, the canister surrounds the vapor vent/rollover valve which may include a gravity pressure relief valve and a vacuum relief valve. In another embodiment a pressure relief valve and adjacent storage canister are disposed in a common housing for positioning inside a small engine fuel tank.

Abstract: A combination fuel vapor storage canister and vapor vent/tipping valve in a common housing with ports for connection to a fuel tank, a purge line and an atmospheric vent. The vapor vent/tipping valve includes a pressure relief valve which prevents vapor venting until a predetermined vapor pressure is reached; and, the pressure relief valve may also include a vacuum relief valve.

Abstract: A small engine fuel tank vapor emission system is described with a separate surge tank having a vapor vent/rollover valve and separate a vapor storage space which may be found in a common housing or remote from the surge tank. The surge tank is located at a level above the fuel tank and is connected to have its inlet receive vapor from the fuel tank. The outlet of the vapor vent/rollover valve is connected to supply vapor purge flow to the engine air inlet either directly or through the storage space, which may be charged with adsorbent.

Abstract: A fuel vapor emission system for small engine gas tank which does not require redesign or retooling for manufacturing of the tank. A new filler tube has the lower end positioned to cause fuel to rise rapidly in the tube before the tank is full, signaling the operator to stop refueling and maintain a vapor dome in the tank when the filler cap is replaced. A vapor vent valve is disposed in a separate access opening and includes a float operated rollover valve. The vent valve opens when a predetermined positive pressure is reached in the tank; and, a reverse flow vacuum relief valve is disposed in the vent valve. The outlet of the vent valve is intended to be connected to either a storage canister or the engine air inlet.

Abstract: A fuel tank assembly for small engines having a vapor storage canister disposed within the tank in the vapor dome with an atmospheric vent line to the canister through the tank wall and a canister vapor outlet line also through the tank wall. A fuel vapor vent valve is disposed in the vapor dome of the tank with the vent valve outlet connected to the canister inlet. A fuel filler tube extends through the tank wall to a desired depth to prevent vapor from escaping through the filler tube when the fuel level rises to the lower end of the filler tube and alerts the operator by rapid rise of fuel in the filler tube.

Abstract: A combination fuel tank rollover valve, float actuated fill vent shutoff and tank vapor pressure relief valve assembly in a common housing for assembly into a single access opening in the tank. A header containing the pressure relief valve is sealed over the tank access opening and has an extension member attached to the undersurface of the header with an extension neck extending through the access opening. An interchangeable vent float valve subassembly is attached to the end of the neck before attachment of the extension to the header and assembly on the tank. Tanks of different depth can be accommodated simply by using extension members having a correspondingly different length necks, while the float valve subassembly and header are interchangeable.

Abstract: A fuel level responsive vent valve assembly adaptable to a variety of different mounting requirements in a vehicle fuel tank. In general, the vent valve assembly comprises a standard, valve body, a top cover adapted to mate with the standard valve body at a vent outlet interface for a sealed vapor venting connection, and separately formed longitudinal connector means having a preassembly end for preassembly to a standard interface on the lower surface of the top cover, and an assembly end for longitudinally locking the standard valve body to the top cover. The standard assembly end of the longitudinal connectors can be varied in length to accommodate different valve height mounting requirements in different fuel tank applications. In a preferred embodiment the longitudinal connectors comprise metal pins or rods which can be pre-formed or cut to length to accommodate the standard valve body at different distances from the top cover.

Abstract: A smooth-opening, low hysteresis, pressure-operated ball head valve connected between a fuel tank and vapor trap in a vehicle fuel system for providing smooth, two-stage, low hysteresis vapor flow. The ball valve element is positioned within a cylindrical retainer in the valve body, and the dimensions of the various valve orifices and the geometry of the retainer are determined in view of a specified lift off pressure and ball weight to achieve these flow characteristics.