Patent ID: 6481592
Filing Date: 2002-11-19
Classification: B60K,F16K,Y10S

Abstract:
A vehicle fuel tank vent comprising:a structure providing an orifice defined by a radially inwardly and peripherally extending edge, the orifice defining a central axis, an axially movable first vacuum relief valve member configured to normally engage and close the orifice and to open the orifice upon a certain vacuum condition occurring in the tank, a spring urging the first valve member into engagement with the orifice, the first vacuum relief valve member providing a frustoconical outer wall facing and extending axially into the orifice, and the outer wall presenting an outer lubricious sealing surface to close the orifice, wherein the first vacuum relief valve member is provided with a central venting orifice bounded by an annular frustoconical inner wall opening radially inwardly and presenting an inner lubricious sealing surface, and an axially movable second excess pressure relief valve member configured to normal close the central venting orifice and to open the central venting orifice upon an excess pressure condition occurring in the tank the second excess pressure relief valve member engaging the inner lubricious sealing surface.