Patent ID: 6511283
Filing Date: 2003-01-28
Classification: F02M,F04D

Abstract:
An electric fuel pump comprising:a disk-shaped impeller (30) including: a number of vanes (31) formed at the outer edge thereof and projected circumferentially; a plurality of partitions (32) extended between the vanes (31); and a plurality of vane grooves (33) formed by the partitions (32) and the vanes (31) provided at the front and rear of the partitions (32); a motor section (3) for rotationally driving the impeller (30); and a pump casing (7) which houses the impeller (30), forms an arc belt-shaped pump flow path (13) extending along the outer edge of the impeller (30), and has a sucking inlet (14) at the one end of the pump flow path (30) and a discharge outlet (15) at the other end thereof, wherein each of the vanes (31) each includes a vane segment (31A) on the side of the one end face of the impeller (30) and a vane segment (31B) on the side of the other end face of the impeller (30); the vane segment (31A) on the side of the one end face and the vane segment (31B) on the side of the other end face are staggered by a prescribed distance (d) circumferentially of the impeller (30), and in the vane segment (31A) on the side of the one end face and the vane segment (31B) on the side of the other end face; a plurality of guiding faces (31a, 31b) are formed which extend from the sides of the one end face and the other end face of the impeller (30) to the outermost periphery of the impeller (30) to guide fuel; the partitions (32) each has guiding face (32a, 32b) which extend from the sides of the one end face and the other end face of the impeller (30) to guide the fuel; and the grooves (33) each includes: a groove segment (33A) formed by a guiding face (31b) which extends from the side of the one end face of the impeller (30) to the outermost periphery of the impeller (30) to guide the fuel and the vane segment (31A) on the side of the one end face of the impeller; a groove segment (33B) formed around the partition (32) where both guiding faces (32a, 32b) of the partition (32) are opposite to each other; and a groove segment (33C) formed by a guiding face (31a) which extends from the side of the other end face of the impeller (30) to the outermost periphery of the impeller (30) to guide the fuel and the vane segment (31B) on the side of the other end face.