Aisan Kogyo Kabushiki Kaisha

Kenzo Nagasaka

Yoshihiro Takami

Takayuki Usui

Koichi Iwata

A fuel pump improved in pump efficiency is provided. An impeller rotating in a pump casing has an approximately disk-shaped configuration with a group of recesses formed in a region extending along the outer peripheries of the obverse and reverse sides of the impeller. The recesses are repeatedly arranged in the circumferential direction at a distance between each pair of adjacent recesses. The radially outer end face of each recess slantingly extends radially outward from a middle plane in the direction of thickness toward the obverse and reverse sides. With this fuel pump, the incidence of separation or vortex formation in the flow of fuel is minimized, and a high pump efficiency can be obtained.

Fuel pump

A fuel pump capable of using the pump efficiency most efficiently without reducing the useful service life is provided. A relatively large clearance allowing for the expected amount of wear is ensured in a region where the flow passage groove pressure is low. In a region where the flow passage groove pressure is high, it is unnecessary to allow for the wear. Therefore, the clearance is set relatively small.

A fuel pump in which a terminal plate can be liquid-tightly mounted to a body upper and prevented from being dislodged from the body upper without the need of other component parts is provided. The terminal plate is formed with a cut and raised portion for preventing dislodging. When the terminal plate is inserted into a terminal plate through-hole having a step portion, a projection and a press-fit portion, the cut and raised portion is closed by being pressed with the projection and allowed to reach the step portion without contacting the press-fit portion. Then, the cut and raised portion returns to its natural configuration. Thus, the terminal plate is prevented from being dislodged to fall into the fuel pump. Because the press-fit portion is not damaged when the terminal plate is inserted, the terminal plate can be placed in liquid-tight contact with the body upper block.

Growing community of inventors

Obu, Japan

Kenzo Nagasaka