Abstract: A fuel pump includes an impeller and a casing member. The impeller defines a plurality of vane grooves arranged in a circumferential direction. The casing member receives the impeller, and the casing member defines therein a pump passage configured to have an arcuate shape along the vane grooves. The discharge passage is provided downstream of the pressurizing passage. The discharge passage has a width narrower than a width of the pressurizing passage, and the discharge passage is positioned toward a radially outer wall of the pressurizing passage. The pressurizing passage includes a throttle part that extends from a starting point to an inlet of the discharge passage. The throttle part has a first width at the starting point, which corresponds to the width of the pressurizing passage, and a second width at the inlet, which corresponds to the width of the discharge passage.

Abstract: A motor includes a rotor, a commutator, a brush, and a bias member. The commutator has a rectifying surface. The commutator rectifies an electric current supplied to the rotor through the rectifying surface. The rotor is rotated by being supplied with the electric current. The brush makes contact with the commutator via the rectifying surface. The rotor is supplied with the electric current through the brush. The brush starts making contact with the commutator on an entry side of the brush as the rotor and the commutator rotate with respect to the brush along a rotative direction and the commutator intermittently makes contact with the brush. The bias member biases the brush toward the entry side.

Abstract: A fuel pump includes an impeller and a casing member. The impeller defines a plurality of vane grooves arranged in a circumferential direction. The casing member receives the impeller, and the casing member defines therein a pump passage configured to have an arcuate shape along the vane grooves. The discharge passage is provided downstream of the pressurizing passage. The discharge passage has a width narrower than a width of the pressurizing passage, and the discharge passage is positioned toward a radially outer wall of the pressurizing passage. The pressurizing passage includes a throttle part that extends from a starting point to an inlet of the discharge passage. The throttle part has a first width at the starting point, which corresponds to the width of the pressurizing passage, and a second width at the inlet, which corresponds to the width of the discharge passage.

Abstract: The outer periphery of a disc-shaped impeller is surrounded with an annular portion. Vane grooves are formed on the inner circumferential side of the annular portion on both sides in the axial direction. The vane grooves, which are adjacent to each other, are partitioned with a partition wall that is bent at the substantially center in the axial direction. The partition wall is bent to the rear side relative to the rotative direction. The vane grooves, which are formed on both sides in the axial direction, are partitioned with a wall from each other partially on the radially inner side thereof. A partition wall, which is arranged on the rear side of the vane groove relative to the rotative direction, has a fore face that is on the fore side of the partition wall relative to the rotative direction. The fore face is an inclined flat face that is inclined to the rear side relative to the rotative direction, as extending to the radially outer side.

Abstract: A fuel pump to be disposed in a fuel tank to supply pressurized fuel to an internal combustion engine includes a motor section, a pump section including an impeller driven by the motor section and a cylindrical pump housing having a pump passage extending along the outer periphery of the impeller so as to pressurize fuel, a suction filter and a feed passage member disposed around the inlet port of the pump passage. The feed passage member has a smooth feed passage connecting the pump passage and the suction filter. The feed passage tapers off toward an inlet port of the pump passage that opens at a peripheral portion of the pump housing.

Abstract: A motor includes a rotor, a commutator, a brush, and a bias member. The commutator has a rectifying surface. The commutator rectifies an electric current supplied to the rotor through the rectifying surface. The rotor is rotated by being supplied with the electric current. The brush makes contact with the commutator via the rectifying surface. The rotor is supplied with the electric current through the brush. The brush starts making contact with the commutator on an entry side of the brush as the rotor and the commutator rotate with respect to the brush along a rotative direction and the commutator intermittently makes contact with the brush. The bias member biases the brush toward the entry side.

Abstract: A fuel pump to be disposed in a fuel tank to supply pressurized fuel to an internal combustion engine includes a motor section, a pump section including an impeller driven by the motor section and a cylindrical pump housing having a pump passage extending along the outer periphery of the impeller so as to pressurize fuel, a suction filter and a feed passage member disposed around the inlet port of the pump passage. The feed passage member has a smooth feed passage connecting the pump passage and the suction filter. The feed passage tapers off toward an inlet port of the pump passage that opens at a peripheral portion of the pump housing.

Abstract: The outer periphery of a disc-shaped impeller is surrounded with an annular portion. Vane grooves are formed on the inner circumferential side of the annular portion on both sides in the axial direction. The vane grooves, which are adjacent to each other, are partitioned with a partition wall that is bent at the substantially center in the axial direction. The partition wall is bent to the rear side relative to the rotative direction. The vane grooves, which are formed on both sides in the axial direction, are partitioned with a wall from each other partially on the radially inner side thereof. A partition wall, which is arranged on the rear side of the vane groove relative to the rotative direction, has a fore face that is on the fore side of the partition wall relative to the rotative direction. The fore face is an inclined flat face that is inclined to the rear side relative to the rotative direction, as extending to the radially outer side.

Abstract: A regenerative pump according to the present invention includes a rotatable impeller disposed in a housing. The impeller has a plurality of radially extending vane members spaced apart about a periphery of the impeller. Each vane member has circumferentially-facing upstream and downstream surfaces, relative to an operational direction of impeller rotation. At least one of the upstream and downstream surfaces of each vane member has a proximal portion which is inclined or curved away from the operational rotation direction, and a distal portion which is inclined or curved towards the operational rotation direction. The curved/inclined surface advantageously enhances pump efficiency.