主权项 |
1. A fuel pump comprising:
a housing defining a pump chamber, a driven and an idler toothed gears rotatably mounted in said pump chamber so that said driven and idler gears mesh with each other at a predetermined location in said pump chamber, a fluid inlet formed through said housing and open to an inlet subchamber of said pump chamber, said inlet subchamber being positioned at one side of said predetermined location, a fluid outlet formed through said housing and open to an outlet subchamber of said pump chamber, said outlet subchamber being positioned at the other side of said predetermined location, a pressure relief passageway which fluidly connects said inlet subchamber to said outlet subchamber, a valve disposed in series with said pressure relief passageway, and a control circuit which controls an actuation of said valve between an open and a closed position, wherein said driven gear and said idler gear have the same number of teeth, wherein at least two angularly spaced teeth of said driven gear and at least two angularly spaced teeth of said idler gear each have a through notch, said driven and idler gears being angularly oriented so that the notched teeth in both said driven gear and said idler gear mesh each revolution of the gears and fluidly connect said inlet subchamber to said outlet subchamber at a plurality of different angular positions of said gears. |