Patent ID: 6851443

Claim:
A device for preventing resonance in a fuel vapor pressure management apparatus of a fuel system supplying fuel to an internal combustion engine, the fuel vapor pressure management apparatus performing leak detection on a headspace of the fuel system, performing excess negative pressure relief of the headspace, and performing excess positive pressure relief of the headspace, the device comprising: a housing defining an interior chamber, the housing including a wall projecting into the interior chamber and surrounding an axis; and a pressure operable device separating the interior chamber into first and second portions, the pressure operable device including a poppet movable along the axis, the poppet includes a surface matingly and telescopically engaging the wall so as to define a variable volume sub-chamber within the second portion of the interior chamber; wherein the sub-chamber and the telescopic movement of the poppet with respect to the wall define a dashpot that damps movement of the poppet while the fuel vapor pressure management apparatus performs excess positive pressure relief.