PURPOSE: To discharge vapor positively by disposing a suction port and a discharge opening opposedly interposing an impeller accommodating part in a pump part in between and providing an air vent hole for piercing a pump casing at a part between the suction port and the discharge opening.
CONSTITUTION: A fuel pump device is formed of a pump part 3, a motor part 4 and a terminal holder part 5 disposed in a cylindrical housing 2. Fuel sucked from a suction port 10 by the rotation of an impeller 8, accommodated in a shallow circular recessed part 7 formed at the axial end face of the outer casing 6b of a pump casing 6, by the motor part 4 is discharged by the pump part 3 from a discharge opening 11 into the housing 2 and delivered outside through a fuel outlet pipe 21 with a built-in check valve 20. In this case, an air vent hole 32 piercing the outer casing 6b is provided at a part between the suction port 10 and the discharge opening 11. Vapor is therefore caught before reaching the suction port 10 and can be discharged outside a fuel pump 1.
ARAI HIDEO
NAKAMURA KOJI
