Fuel supply system

• US 20020152999A1
• Filed: 12/13/2001
• Published: 10/24/2002
• Est. Priority Date: 06/15/1999
• Status: Active Grant

• Current Assignee: Daimler AG (Mercedes-Benz Group AG)
• Original Assignee: DaimlerChrysler AG (Mercedes-Benz Group AG)
• Inventors: Stengel, Thomas, Plog, Carsten, Matt, Martin, Pfeffer, Viktor, Holder, Eberhard, Kemmler, Roland
• Granted Patent: US 6,622,664 B2
• Time in Patent Office: Days
• US Class Current: 123/575
• CPC Class Codes: F02D 19/0649 Liquid fuels having different boiling temperatures, volatilities, densities, viscosities, cetane or octane numbers
• CPC Class Codes: F02D 19/0665 Tanks, e.g. multiple tanks
• CPC Class Codes: F02D 19/0671 Means to generate or modify a fuel, e.g. reformers, electrolytic cells or membranes
• CPC Class Codes: F02D 19/0678 Pressure or flow regulators therefor; Fuel metering valves therefor
• CPC Class Codes: F02D 19/081 Adjusting the fuel composition or mixing ratio; Transitioning from one fuel to the other
• CPC Class Codes: F02M 1/165 Vaporizing light fractions from the fuel and condensing them for use during starting
• CPC Class Codes: F02M 25/14 adding anti-knock agents, not provided for in subgroups F02M25/022 - F02M25/10
• CPC Class Codes: F02M 33/00 Other apparatus for treating combustion-air, fuel or fuel-air mixture combustion-air cleaners F02M35/00; arrangements for purifying liquid fuel F02M37/22
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y02T 10/30 Use of alternative fuels, e.g. biofuels

Abstract

In a fuel supply system for an internal combustion engine including a fuel tank, a fuel processing apparatus to which fuel from the tank is supplied and which separates the fuel into different fractions, the fuel and the fractions are mixed in a mixing chamber according to a performance graph stored in a control unit depending on the operating state of the engine and the mixture is then supplied to the engine in a controlled manner.

Claims

1. A fuel supply system for an internal combustion engine including a fuel tank for receiving and storing liquid fuel, a fuel processing apparatus having a fuel input connected to said fuel tank for receiving fuel therefrom, and being capable of dividing said fuel from said fuel tank into at least two fractions having different properties, means for supplying at least one of said fractions to said engine including a fuel flow control device for supplying said fuel fractions and said fuel to said engine in proportions selected depending on the momentary operating state of said engine, said fuel processing apparatus including a mixing structure for mixing the fuel proportions received from said flow control device and forming a mixture for supply to said internal combustion engine.

2. A fuel supply system according to claim 1, wherein a control unit is provided adapted to control said fluid flow control devices and including a performance graph having stored therein the optimum values for the fuel mixture for any engine operating state and providing said optimum value for controlling the flow control devices so as to provide the optimum fuel mixture.

3. A fuel supply system according to claim 2, wherein said mixing structure is connected to different fuel or fuel fraction supply lines through which said fuel or fuel fractions are supplied to said mixing structure and said different fuel supply lines include each a fuel flow control valve connected to said control unit for controlling said fuel flow control valves depending on the momentary engine operating state.

4. A fuel supply system according to claim 3, wherein said fuel fraction supply lines include each a separate tank for storing a certain amount of said fuel fraction.

5. A fuel supply system according to claim 3, wherein said mixing structure is disposed in a fuel distributor of a fuel injection system of an internal combustion engine, which supplies a prepared fuel mixture to the injectors of a fuel injection system of said internal combustion engine.

6. A fuel supply system according to claim 1, wherein said fuel fractions differ from each other with regard to at least one of their boiling point, their sulfur content, their cetane number, and their reduction medium content.

7. A fuel supply system according to claim 1, wherein at least one of said fuel fractions is gaseous.

8. A fuel supply system according to claim 3, wherein said fuel flow control device includes a separate flow control valve for each fuel or fuel fraction supply line.

9. A fuel supply system according to claim 1, wherein, under certain operating conditions, only a particular fuel fraction or the fuel from said tank is provided to the engine.

10. A fuel supply system according to claim 1, wherein said fuel fractions are mixed under certain operating conditions so as to provide a mixture corresponding to the original fuel present in the tank.

11. A fuel supply system according to claim 1, wherein said fuel supply system is installed in a vehicle including a truck, a passenger car and a bus.