Patent ID: 7165932

Claim:
A fuel pump for a motor vehicle, the fuel pump pressurizing fuel for delivery to an engine, the fuel pump comprising: a housing; a motor situated in the housing and driving a shaft, the shaft defining a central axis; a single sided impeller connected to the shaft for rotation and for axial translation relative to shaft, the impeller having opposed axially facing surfaces including a body-side surface and a cover-side surface; the cover-side surface defining first and second impeller flow channels extending circumferentially around the impeller, the impeller further including a plurality of vanes, each of the first and second impeller flow channels having a portion of the vanes positioned at least partially therein, the second impeller flow channel being positioned radially inward of the first impeller flow channel, the impeller defining a flow passageway extending through the impeller; a cover attached to the housing; the cover having a cover surface defining first and second cover flow channels extending circumferentially around the cover, the first cover flow channel receiving fuel from a first inlet formed in the cover and the second cover flow channel receiving fuel from a second inlet formed in the cover, the first cover flow channel at least partially aligned with the first impeller flow channel and having an inlet end receiving lower pressure fuel and an outlet end providing higher pressure fuel, the outlet end extending radially inwardly for fluid communication with the flow passageway of the impeller, and the second cover flow channel at least partially aligned with the second impeller flow channel and having an inlet end receiving fuel and an outlet end providing fuel to a second outlet passageway; a body defined inside the housing, the body defining an impeller chamber having a body surface, the impeller chamber sized to receive the impeller, the body further defining a first outlet passageway positioned to fluidically connect to the flow passageway of the impeller to receive higher pressure fuel for delivery to the engine.