A first connecting pipe of an electromagnetic valve connects with the fuel
tank, and a second connecting pipe connects with a canister. A spring
urges a moving core and a first valve body in a closing direction of a
electromagnetic valve. A shaft of the first valve body includes a
fluid-amount controlling portion on the top. The fluid-amount controlling
portion is inserted to the communicating passage while a contact member
of bellows seats on a convex of a rubber member, and is tapered in an
inserted direction. When a coil is energized, the first valve body is
lifted in the direction in which the fluid-amount controlling portion
retracts from the communicating passage.