Fuel system for internal combustion engine

• US 20070221180A1
• Filed: 04/26/2007
• Published: 09/27/2007
• Est. Priority Date: 10/28/2004
• Status: Active Grant

• Current Assignee: Paul Hutchinson
• Original Assignee: Paul Hutchinson
• Inventors: Hutchinson, Paul
• Granted Patent: US 7,503,315 B2
• Time in Patent Office: Days
• US Class Current: 123/525
• CPC Class Codes: F02D 35/0092 by means of fuel injection
• CPC Class Codes: F02D 41/0032 Controlling the purging of the canister as a function of the engine operating conditions
• CPC Class Codes: F02M 1/165 Vaporizing light fractions from the fuel and condensing them for use during starting
• CPC Class Codes: F02M 25/08 adding fuel vapours drawn from engine fuel reservoir electrical control of purge system F02D41/003
• CPC Class Codes: F02M 31/186 with simultaneous mixing of secondary air
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

An internal combustion engine is supplied with combustion air via an inlet manifold. A throttle valve controls the amount of air admitted to the combustion chamber. A fuel injector is provided for injecting liquid fuel into the airflow in the inlet manifold downstream of the throttle valve. A vaporiser is located upstream of the throttle valve. Under light load conditions most if not all of the fuel required by the engine is supplied by the vaporiser. The throttle valve will accordingly be wider open, for any particular power output, than it would be if it controlled only combustion air. At high power outputs (typically after the throttle valve has reached a wide-open state) fuel is supplied by the injector 11 and the output of the vaporiser is reduced so that more air can be admitted to the cylinder for effective combustion of the liquid fuel supplied through the injector.

Claims

1. An internal combustion engine comprising:

at least one combustion chamber;

an inlet manifold for supplying combustion air to the combustion chamber;

means for supplying fuel to the combustion chamber, the means for supplying fuel comprising first means for supplying a fuel vapor to the inlet manifold and second means for supplying liquid fuel to the combustion chamber or the inlet manifold; and

control means for controlling the first and second fuel supply means so that, under light load conditions, at least some of the fuel supplied to the combustion chamber is supplied by the first means and, under heavy load conditions, the output of the first means is reduced to increase the amount of air supplied to the combustion chamber.

2. The internal combustion engine according to claim 1 including means for controlling the admission of combustion air to the inlet manifold, wherein during a first phase of operation of the engine, power output is increased by progressively opening the combustion air control means and progressively increasing the amount of fuel supplied by the first means, and, during a second phase of operation of the engine, the means for controlling the admission of combustion air is maintained at a constant state and power output is increased by supplying progressively more fuel from the second means.

3. The internal combustion engine according to claim 2 wherein the substantially constant state is a wide-open throttle state.

4. The internal combustion engine according to claim 1 wherein the first means is a vaporiser.

5. The internal combustion engine according to claim 1 wherein the second means is a fuel injector.

6. The internal combustion engine according to claim 1 wherein the engine is an Otto engine and a throttle valve is located in the inlet manifold downstream of the first means.

7. The internal combustion engine according to claim 6 wherein the second means is a fuel injector for injecting fuel into one of at least the inlet manifold and the cylinder downstream of the throttle valve.

8. The internal combustion engine according to claim 1 wherein, under light load conditions, substantially all of the fuel supplied to the combustion chamber is supplied by the first means.

9. The internal combustion engine according to claim 1 wherein the engine is a diesel engine.

10. The internal combustion engine according to claim 1 wherein at maximum power output all fuel required by the engine is supplied by the second means.

13. The internal combustion engine according to claim 2 wherein the substantially constant state is a wide-open throttle state.

20. The internal combustion engine according to claim 1 wherein at maximum power output all fuel required by the engine is supplied by the second fuel supply device.

11. An internal combustion engine comprising:

at least one combustion chamber;

an inlet manifold for supplying combustion air to the combustion chamber;

a fuel supply device for supplying fuel to the combustion chamber, the fuel supply device comprising a first device for supplying a fuel vapor to the inlet manifold and second device for supplying liquid fuel to the combustion chamber or the inlet manifold; and

a control device for controlling the first and second fuel supply devices so that, under light load conditions, at least some of the fuel supplied to the combustion chamber is supplied by the first fuel supply device and, under heavy load conditions, the output of the first fuel supply device is reduced to increase the amount of air supplied to the combustion chamber.

12. The internal combustion engine according to claim 11 including a device for controlling the admission of combustion air to the inlet manifold, wherein during a first phase of operation of the engine, power output is increased by progressively opening the combustion air control device and progressively increasing the amount of fuel supplied by the first fuel supply device, and, during a second phase of operation of the engine, the device for controlling the admission of combustion air is maintained at a constant state and power output is increased by supplying progressively more fuel from the second fuel supply device.

14. The internal combustion engine according to claim 11 wherein the first fuel supply device is a vaporiser.

15. The internal combustion engine according to claim 11 wherein the second fuel supply device is a fuel injector.

16. The internal combustion engine according to claim 11 wherein the engine is an Otto engine and a throttle valve is located in the inlet manifold downstream of the first fuel supply device.

17. The internal combustion engine according to claim 16 wherein the second fuel supply device is a fuel injector for injecting fuel into one of at least the inlet manifold and the cylinder downstream of the throttle valve.

18. The internal combustion engine according to claim 11 wherein, under light load conditions, substantially all of the fuel supplied to the combustion chamber is supplied by the first fuel supply device.

19. The internal combustion engine according to claim 11 wherein the engine is a diesel engine.