Quiet running electric fuel pump for motor vehicle - has gear shaped impeller with sloping teeth for controlled axial thrusts

摘要

The fuel pump has a rotating gearwheel (22) inside a gear ring (25) with inwardly facing teeth, the ring being much larger than the wheel. The gearwheel meshes on one side of the outer ring and forces the ring to rotate around the wheel. The fuel is forced in and out of lateral ducts by the changing volume of the pump chamber formed between the wheel and the ring. The wheel and ring rotate between fixed outer plates. The sloping profile of the gear teeth provide an even reaction force on the gear wheel and prevent it from vibrating with the pump action. ADVANTAGE - No pulsating pump vibrations, quiet running.