Abstract: The present invention provides a check valve including a seal door which is normally spring biased towards a closed position but which is responsive to a flow of fuel for displacing to an open position to allow fuel to pass in a first direction and for thereafter preventing passage of liquid fuel or fuel vapors in a second direction. According to the invention, the check valve is disposed at a lower end or in the midsection of a fuel tank filler pipe. The check valve includes an annular housing having a concentric annular valve seat portion including a frustoconical valve seat facing toward the lower end of the filler pipe. A seal door attached to a hinge member is resiliently biased toward engagement with the valve seat by a spring member. The inflow of fuel overcomes the bias of the spring member which causes the seal door to displace to an open position to allow passage of fuel to the fuel tank.

Abstract: A combination vent valve/purge valve apparatus (10) for an automotive fuel vapor recovery system canister (14) comprises a purge valve (26) and a vent valve (16) in a single housing. When open, the vent valve (16) allows outside air to enter the canister (14). The purge valve (26), when open, allows fuel vapor to flow from the canister (14) into a vacuum source (12). A gas channel (28, 130, 168) extends between a vent chamber (18) within the vent valve (16) and a purge chamber (28) within the purge valve (26). When the purge valve (26) is open and a purge plunger (86) within the purge chamber (28) is positioned away from the gas channel (28, 130, 168), the manifold vacuum draws air from one side of a diaphragm (126) within the vent chamber (18) drawing the diaphragm (126) and a vent plunger (152) downward against a spring to close the vent valve (16). When the purge plunger (86) is positioned to block the gas channel (28, 130, 168), the spring forces the vent plunger (152) upward to open the vent valve (16).

Abstract: Modified pole piece and armature members reduce the noise level for purge valves, particularly at low temperatures. A raised outer ring positioned on the lower end of the pole piece mates with a raised step on the upper end of the armature. Alternatively, a noise disk made from a flexible energy absorbing material, such as fluorosilicone, could be positioned between the pole piece and armature; also the valve member positioned on the lower end of the armature could be made from the same material.