| 摘要 |
<p>A tank vent control system includes a valve container adapted to be mounted in a vehicle fuel tank and formed to include an interior chamber, a chamber inlet, a chamber outlet, and a valve positioned to move up and down in the interior chamber to control the flow of liquid fuel and fuel vapor from the interior chamber through the chamber outlet. The valve includes an outlet closure sized to engage and close the chamber outlet and an exterior wall. The valve container includes a lower interior portion bounding a lower region of the interior chamber and surrounding the exterior wall of the valve to define a vent passage therebetween communicating with the chamber inlet. The valve container also includes an upper interior wall bounding an upper region of the interior chamber and engaging the exterior wall of the valve upon movement of the valve to a snap-closure position to allow formation of pressure differential between the lower and upper regions of the interior chamber so that the valve is assisted in moving quickly to a closed position closing the chamber outlet.</p> |
