Patent ID: 6953027

Claim:
A fuel vapor pressure management apparatus comprising: a housing defining an interior chamber, the housing including first and second ports communicating with the interior chamber; and a pressure operable device including a diaphragm separating the interior chamber into a first portion in fluid communication with the first port and a second portion in fluid communication with the second port, the diaphragm including a central portion movable along an axis, a peripheral portion fixed with respect to the housing, and an intermediate portion coupling the central and peripheral portions, the intermediate portion having at least one aperture and sections engaging each other to prevent fluid flow through the at least one aperture, a first arrangement of the pressure operable device occurs when there is a first negative, pressure level at the first port relative to the second port and the diaphragm is in a nearly undeformed configuration, a second arrangement of the pressure operable device permits a first fluid flow through the at least one aperture from the second port to the first port when the diaphragm is in a first deformed configuration, and a third arrangement of the pressure operable device permits a second fluid flow through the at least one aperture from the first port to the second port when the diaphragm is in a second deformed configuration.