Abstract: A fuel pump includes a pump device for pumping fuel. The fuel pump further includes a motor device that has a commutator and an armature including a shaft. The commutator commutating electricity supplied to the armature for rotating the armature to drive the pump device. The fuel pump further includes a brush supplying electricity to the armature by making contact with the commutator. The fuel pump further includes a bearing member supporting the shaft. The fuel pump further includes a holder including a partition wall for supporting the bearing member. The partition wall electrically insulates the bearing member from the brush. The bearing member has a first bearing end surface on a side of the commutator. The partition wall has a wall end surface on a side of the commutator. The first bearing end surface is on an opposite side of the commutator with respect to the wall end surface.

Abstract: In a fuel pump having a high pump efficiency, an annular portion is formed on an outer periphery of an impeller to let one- and opposite-side blade grooves be independent of each other. Then, various improvements are made such as tilting front and rear wall surfaces of the blade grooves in a predetermined direction, forming one- and opposite-side blade grooves in a zigzag fashion, forming a guide surface in a communicating passage of a pump housing, and forming communicating holes in an impeller.

Abstract: Two-inner gears are overlapped with each other through a partition wall and are eccentrically arranged at an inner peripheral side of an outer gear, and eccentric directions of both the inner gears are shifted from each other by 180° to the opposite side. By this, loads in an outer diameter direction due to a rise in fuel pressure affect one outer gear from the two inner gears oppositely to each other by 180°, so that an eccentric load is not generated, and sliding resistance of the outer gear to a cylindrical casing becomes small. Further, the number of teeth of the outer gear is made odd, and the number of teeth of the inner gears is made even.

Abstract: A turbine pump includes a casing having an inlet, an outlet and front and rear arc-shaped pump passages and an impeller. The impeller has plural impeller partitions respectively disposed between every two of the blades thereby forming impeller grooves at front and rear sides of the partitions and an outer ring at the peripheral edge of the blades. Each impeller groove, each of pump passage and the outer ring form a space for circulating fuel. The outside diameter of the impeller is smaller than the pump passages so that the impeller does not contact the pump passages.

Abstract: A turbine fuel pump for smoothly flowing fuel in a fuel inlet passage, preventing a pressure loss at a start end of a pump flow passage to prevent generation of a local negative pressure, thereby increasing pump efficiency. The turbine fuel pump includes an impeller with blades and blade grooves, and a pump housing having first and second housings for rotatably storing the impeller. The first housing has a C-shaped side groove, a fuel inlet passage which bends at a start end of the side groove toward the center of the first housing, and an opening on an outer side surface. The second housing has a C-shaped side groove, and a fuel outlet opening communicating with a terminal end of the side groove.

Abstract: In a fuel pump having a high pump efficiency, an annular portion is formed on an outer periphery of an impeller to let one- and opposite-side blade grooves be independent of each other. Then, various improvements are made such as tilting front and rear wall surfaces of the blade grooves in a predetermined direction, forming one- and opposite-side blade grooves in a zigzag fashion, forming a guide surface in a communicating passage of a pump housing, and forming communicating holes in an impeller.

Abstract: Two-inner gears are overlapped with each other through a partition wall and are eccentrically arranged at an inner peripheral side of an outer gear, and eccentric directions of both the inner gears are shifted from each other by 180° to the opposite side. By this, loads in an outer diameter direction due to a rise in fuel pressure affect one outer gear from the two inner gears oppositely to each other by 180°, so that an eccentric load is not generated, and sliding resistance of the outer gear to a cylindrical casing becomes small. Further, the number of teeth of the outer gear is made odd, and the number of teeth of the inner gears is made even.

Abstract: A turbine fuel pump for smoothly flowing fuel in a fuel inlet passage, preventing a pressure loss at a start end of a pump flow passage to prevent generation of a local negative pressure, thereby increasing pump efficiency. The turbine fuel pump includes an impeller with blades and blade grooves, and a pump housing having first and second housings for rotatably storing the impeller. The first housing has a C-shaped side groove, a fuel inlet passage which bends at a start end of the side groove toward the center of the first housing, and an opening on an outer side surface. The second housing has a C-shaped side groove, and a fuel outlet opening communicating with a terminal end of the side groove.

Abstract: Two inner gears are overlapped with each other through a partition wall and are eccentrically arranged at an inner peripheral side of an outer gear, and eccentric directions of both the inner gears are shifted from each other by 180° to the opposite side. By this, loads in an outer diameter direction due to a rise in fuel pressure affect one outer gear from the two inner gears oppositely to each other by 180°, so that an eccentric load is not generated, and sliding resistance of the outer gear to a cylindrical casing becomes small. Further, the number of teeth of the outer gear is made odd, and the number of teeth of the inner gears is made even.

Abstract: A turbine pump includes a casing having an inlet, an outlet and front and rear arc-shaped pump passages and an impeller. The impeller has plural impeller partitions respectively disposed between every two of the blades thereby forming impeller grooves at front and rear sides of the partitions and an outer ring at the peripheral edge of the blades. Each impeller groove, each of pump passage and the outer ring form a space for circulating fuel. The outside diameter of the impeller is smaller than the pump passages so that the impeller does not contact the pump passages.

Abstract: Two inner gears are overlapped with each other through a partition wall and are eccentrically arranged at an inner peripheral side of an outer gear, and eccentric directions of both the inner gears are shifted from each other by 180° to the opposite side. By this, loads in an outer diameter direction due to a rise in fuel pressure affect one outer gear from the two inner gears oppositely to each other by 180°, so that an eccentric load is not generated, and sliding resistance of the outer gear to a cylindrical casing becomes small. Further, the number of teeth of the outer gear is made odd, and the number of teeth of the inner gears is made even.