Patent ID: 7062967
Filing Date: 2006-06-20
Classification: B60K,G01F

Abstract:
1. A fuel tank system providing an electrical indication of fuel level in the fuel tank, said system comprising: a fuel tank having a bottom surface and a top surface in spaced relation thereto; an acoustic transducer mounted in said top surface, said transducer transmitting an acoustic signal and receiving a reflected signal, said signals traveling along an axis normal to the surface of the fuel; a float for remaining buoyant at the surface of the fuel in the tank, said float having a reflective portion for receiving said acoustic signal and reflecting therefrom said reflected signal; a centering rod parallel to said axis and having an upper end and a lower end, said upper end of said centering rod being fixed at said top surface and in spaced relation to said acoustic transducer, said lower end being located at said bottom surface, and said float being in sliding engagement with said centering rod; said transducer disposed directly above the reflective portion of said float; and an interface circuit connected to said transducer and arranged to measure an elapsed time between transmission of said acoustic signal to receiving of said reflected signal, and produces an output as a function of said elapsed time that is indicative of the fuel level in the fuel tank.