Vapor fuel control apparatus

Claim 1

A fuel vapor control apparatus for use in a fuel system between a gasoline tank and a filter-supporting canister for maintaining the gasoline tank side at a preselected pressure, comprising in combination: a main body of plastic material having an opening therethrough; first valve means movably disposed within said opening of said main body and including a. a valve stem having a tubular portion, a radially inwardly extending end wall portion integrally formed at one end of said tubular portion, a radially outwardly extending end wall portion integrally formed on the periphery of said tubular portion at said one end thereof, and a valve member squeezing portion integrally formed on the inner end of said radially inwardly extending end wall portion defining a central aperture through said valve stem, b. an annular elastic valve member having an inner end portion securely fitted to said end wall portion of said valve stem around said central aperture thereof through said valve member squeezing portion with one end face of said annular valve member being disposed against the outside surface of said end wall portion of said valve stem, an outer tongue portion formed on the peripheral surface of the end wall of said annular valve member facing away from the end wall of said valve stem, and a projecting foot portion also formed on said surface of said annular valve member adjacent to said inner end portion thereof and facing away from the end wall of said valve stem; c. a first spring interposed between said main body and said valve stem for urging said annular elastic valve member carried by said valve stem to move in one direction wherein said outer valve tongue is caused to seat on an inner wall of said main body; and second valve means movably disposed within said first valve means and including d. a plunger extending through said central aperture of said first valve means, e. a circular disc integrally formed on one end of said plunger, having a projecting portion on the face thereof remote from said plunger for maintaining suitable air flow thereby, and f. a second spring interposed between the other end of said plunger and said valve stem of said first valve means for urging said circular disc to move in a direction opposite to said one direction of movement of said annular elastic valve member of said first valve means, wherein said circular disc is maintained seated against said projecting foot portion of said annular elastic valve member; whereby when said gasoline tank is fully filled, said outer tongue portion of said first valve means is released from seating against said inner wall of said main body by the vapor of gasoline, and when said gasoline tank approaches vacuum, said circular disc of said second valve means is released from seating against said projecting foot portion of said first valve means by the atmospheric pressure in said canister.