Method and system for determining level of fuel
View Patent ↗A method and system for determining the level of fuel contained in the tank of a motor vehicle includes a fuel pump disposed in the tank for creating a flow of fuel in the tank. An elongated tube is placed vertically in the tank. The system also includes a venturi tube coupled between the fuel pump and the elongated tube for creating a vacuum as a result of a portion of the flow of fuel therethrough from the fuel pump thereby drawing fuel vapor from the elongated tube at a varying pressure, the pressure decreasing as the amount of fuel vapor in the tank increases. A controller is coupled to the elongated tube for determining the level of fuel in the tank based on the pressure.
1. A system for determining a level of fuel contained in a tank of a motor vehicle containing both fuel and fuel vapor, the system comprising:
a fuel pump disposed in the tank that creates a flow of fuel in the tank and supplies fuel to a fuel rail of the motor vehicle;
an elongated tube placed vertically in the tank;
a venturi tube coupled between the fuel pump and the elongated tube that creates a vacuum as a result of a portion of the flow of fuel through the venturi tube from the fuel pump, and the vacuum created by the venturi tube draws fuel vapor from the elongated tube at a varying pressure, the pressure decreasing as the amount of fuel vapor in the tank increases, and
a controller coupled to the elongated tube for determining the level of fuel in the tank based on the pressure.
2. The system as recited in claim 1 further comprising:
a pressure transducer coupled to the elongated tube and the controller for determining the pressure at an interior of the elongated tube.
3. The system as recited in claim 1 further comprising:
a display coupled to the controller for displaying the level of fuel in the tank.
4. The system as recited in claim 1 wherein the tube has a plurality of perforations along a length of the elongated tube and wherein fuel vapor is drawn through the perforations.
5. The system as recited in claim 1 wherein the elongated tube is constructed of a plastic material.
6. The system as recited in claim 1 wherein the elongated tube is constructed of a metal material.
7. The system as recited in claim 4 wherein the perforations are holes.
8. The system as recited in claim 1 wherein the venturi tube is coupled to the elongated tube via an interconnect tube.
9. A method for determining a level of fuel contained in a tank of a motor vehicle containing both fuel and fuel vapor, the method comprising:
providing a fuel pump that delivers fuel to a fuel rail of the motor vehicle;
creating a flow of fuel in the tank with the fuel pump;
creating a vacuum as a result of a portion of the flow of fuel flowing through a venturi tube;
using the vacuum created by the venturi tube to draw fuel vapor from the fuel tank at a varying pressure, the pressure decreasing as the amount of fuel vapor in the tank increases; and
determining the level of fuel in the tank based on the pressure.
10. The method as recited in claim 9 further comprising displaying the level of fuel in the tank.
11. A method for determining a level of fuel contained in a tank of a motor vehicle containing both fuel and fuel vapor, the method comprising:
creating a flow of fuel in the tank;
creating a vacuum as a result of a portion of the flow of fuel flowing through a venturi tube;
using the vacuum created by the venturi tube to draw fuel vapor from the fuel tank at a varying pressure, the pressure decreasing as the amount of fuel vapor in the tank increases; and
determining the level of fuel in the tank based on the pressure.