Dennison, Meserole, Pollack & Scheiner
Motor-driven fuel pump
 A motor-driven fuel pump including a motor section provided with a driving motor, and a pump section arranged below the motor section and provided with an impeller to be driven by the driving motor. A plurality of pressure compensation hollows are formed on opposite surfaces of a sealing portion of the impeller, and a plurality of communication holes are formed through the sealing portion for communicating the pressure compensation hollows. In another aspect, a plurality of pressure compensation passages are provided to be communicated to a higher pressure side of either a pump chamber defined around outer peripheral vanes of the impeller and a fuel well for receiving a fuel leaked along a sealing portion of the impeller. 
Aisan Kogyo Kabushiki Kaisha
F F F F F F F
F04D F02M F04D F02M F04D F05D F04D
inventional inventional inventional inventional inventional additional inventional
Yasunori Hirofumi Tadashi Kiyoshi Seiichi Naohiro
Takaku Komatsubara Kozawa Kato Harada Natsume