Patent ID: 7621178
Filing Date: 2009-11-24
Classification: G01F

Abstract:
1. A method of determining the volume of fuel in a vehicle fuel tank comprising the steps of providing means for detecting whether the fuel tank is under equilibrium conditions: detecting whether the fuel tank is at equilibrium conditions; if the fuel tank is at equilibrium conditions, the method further comprises the steps of closing the fuel tank, pumping air into or out of the closed volume of the fuel tank and measuring the change in pressure in the fuel tank as a function of time during said pumping to determine the volume of vapour/air in the fuel tank, and calculating the volume of fuel in the tank based upon the determined volume of vapour/air; and if the fuel tank is not at equilibrium conditions, the method further comprises the steps of determining the fuel consumption of the vehicle engine, and calculating the fuel volume based upon the determined fuel consumption and the fuel volume calculated during the most recently detected equilibrium conditions.