Patent ID: 8567628

Claim:
A fuel cap engageable with a fuel tank filler neck, the fuel cap comprising a filler-neck closure including a closure base adapted to mate with a fuel tank filler neck to close a mouth opening into a fuel-conducting passageway formed in the fuel tank filler neck, a pressure-relief valve mounted in a first vent passageway formed in the closure base for movement relative to the closure base from a normal closed position blocking flow of fuel vapor extant in the fuel tank filler neck through the first vent passageway to atmosphere outside of the fuel cap to an opened position allowing flow of pressurized fuel vapor extant in the fuel tank filler neck through the first vent passageway to the atmosphere in response to exposure of the pressure-relief valve to pressurized fuel vapor extant in the fuel tank filler neck and characterized by a positive pressure in excess of a predetermined positive pressure, and a vacuum-relief valve mounted in a second vent passageway formed in the closure base non-concentrically with the first vent passageway for independent movement relative to the closure base from a normally closed position blocking flow of air from the atmosphere through the second vent passageway into the fuel tank filler neck and an opened position allowing flow of air from the atmosphere through the second vent passageway into the fuel tank filler neck in response to exposure of the vacuum-relief valve to fuel vapor extant in the fuel tank filler neck and characterized by negative pressure in excess of a predetermined negative pressure, a handle arranged to overlie the filler-neck closure to form a space therebetween and supported for rotation about an axis of rotation relative to the filler-neck closure, and a valve mover located in the space provided between the handle and the filler-neck closure and configured to mate with the handle to provide means for moving the vacuum-relief valve from the closed position to the opened position in response to rotation of the handle about the axis of rotation in a cap-removal direction to vent any pressurized fuel vapor extant in the fuel tank filler neck through the second vent passageway past the vacuum-relief valve to the atmosphere while the pressure-relief valve remains in the closed position without disrupting movement of the vacuum-relief valve to the opened position in response to exposure of the vacuum-relief valve to fuel vapor extant in the fuel tank filler-neck and characterized by negative pressure in excess of the predetermined negative pressure.