Regenerative pump and method of manufacturing impeller

A fluid pump comprising:

• a housing having a fluid intake port and a fluid discharge port, said housing defining a fluid flow passage;
• an impeller rotatably disposed in said housing, said impeller having a plurality of circumferentially spaced apart and radially extending vane members, each said vane member having a downstream surface and an upstream surface relative to a rotational direction of said impeller,
• wherein at least one of said upstream surface and said downstream surface of each vane member has a radially proximal portion which is inclined in a direction opposite an operational rotation direction of the impeller and a radially distal portion which is inclined in a direction toward the operational rotation direction,
• said impeller further including radially extending partitions extending between adjacent vane members, wherein each said partition extends in a radial direction farther than a boundary between said oppositely inclined proximal and distal portions of said vane members;
• and
• a motive device for rotating said impeller.

A regenerative pump comprising:

• a casing including a suction port, a discharge port and a pump flow passage of an arcuate shape connecting these ports;
• and
• a disk-like impeller rotatably housed in said casing and formed with a number of vane members at a position corresponding to said pump flow passage,
• wherein said impeller is formed in a manner that at least one of upstream-side and downstream-side vane surfaces of each of the vane members comprises a plane section located on a bottom end side of said vane member and inclined backwardly from a rotating direction of said impeller, and another plane section located on an outer peripheral side of said vane member and inclined forwardly with respect to the rotating direction of said impeller.

A fuel pump for provision in a fuel tank of an automobile to pressurize and supply fuel to an internal combustion engine, comprising:

• a cylindrical housing;
• a pump portion which is provided on one end of said housing and draws fuel from the fuel tank and discharges the fuel into said housing;
• a motor portion which is provided in said housing and drives said pump portion;
• and
• a fuel discharge port which is provided on another end of said housing and discharges the fuel which has been discharged from said pump portion and passed inside of said housing,
• said pump portion comprising:
• a casing in which a pump flow passage of an arcuate shape is formed, said pump flow passage including a suction port which is formed on one end thereof and communicates with the fuel tank, and a discharge port which is formed on another end thereof and communicates with the inside of said housing;
• and
• a disk-like impeller which is rotatably housed in said casing and driven for rotation by said motor portion,
• said impeller comprising:
• a plurality of individual vane members between which vane grooves are formed, each of said vane members including a vane surface facing a downstream side of said pump flow passage and another vane surface facing an upstream side of said pump flow passage, said downstream-side vane surface and said upstream-side vane surface being curved in a manner that portions of the vane surfaces on an bottom end side of said vane member are inclined backwardly from a rotating direction of said impeller, and that portions of the vane surfaces on an outer peripheral side of said vane member are inclined forwardly with respect to the rotating direction of said impeller;
• and
• partition walls each of which divides a vane groove between adjacent two of said vane members into a first groove section facing an end surface of said impeller, a second groove section facing another end surface of said impeller, and a communication groove section which connects said first and second groove sections axially at the outer peripheral side.