摘要 |
A vapor isolation valve includes a first chamber in fluid communication with a fuel tank and a second chamber disposed with respect to the first chamber. A diaphragm is disposed between the first and second chambers, has an orifice allowing fluid communication therebetween, and is moveable between a diaphragm open position and a diaphragm closed position. A third chamber is disposed adjacent the first chamber, relative to the diaphragm, and is in fluid communication with an exit passage. The diaphragm open position allows fluid communication between the first and third chambers, and the diaphragm closed position substantially restricts fluid communication therebetween. A pilot valve is disposed between the second and third chambers and is selectively moveable between a pilot open position configured to allow fluid communication between the second and third chambers and a pilot closed position configured to block fluid communication therebetween. |