Procedure to operate a fuel system of an internal combustion engine

• US 7,481,202 B2
• Filed: 06/28/2007
• Issued: 01/27/2009
• Est. Priority Date: 06/28/2006
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Matischok, Marcel, Posselt, Andreas, Lorenz, Marko
• Primary Examiner(s): Moulis; Thomas N
• Application Number:
  US11/823,663
• Publication Number:
  US 20080004786A1
• Time in Patent Office: 579 Days
• Field of Search: 123/497, 123/179.17, 123/198.D, 123/198.DB, 701/29, 701/45, 701/62
• US Class Current: 123/497
• CPC Class Codes: F02D 1/02 not restricted to adjustment of injection timing, e.g. varying amount of fuel delivered
• CPC Class Codes: F02D 2041/225 Leakage detection
• CPC Class Codes: F02D 2200/0606 Fuel temperature
• CPC Class Codes: F02D 2250/02 Fuel evaporation in fuel rails, e.g. in common rails
• CPC Class Codes: F02D 2250/31 Control of the fuel pressure
• CPC Class Codes: F02D 41/0235 in relation with the state of the exhaust gas treating apparatus control of exhaust gas treating apparatus per se F01N
• CPC Class Codes: F02D 41/0255 to accelerate the warming-up of the exhaust gas treating apparatus at engine start
• CPC Class Codes: F02D 41/062 for starting F02D41/061 takes precedence
• CPC Class Codes: F02D 41/064 at cold start F02D41/067 takes precedence
• CPC Class Codes: F02D 41/3082 Control of electrical fuel pumps
• CPC Class Codes: F02D 41/3845 by controlling the flow into the common rail, e.g. the amount of fuel pumped
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

In the operation of a fuel system of an internal combustion engine, the fuel is compressed by a fuel pump and travels by way of at least one fuel injection device into at least one combustion chamber of the internal combustion engine. It is proposed that at least periodically during a phase immediately when starting or just after starting the internal combustion engine, the fuel pump is actuated corresponding to an increased set point pressure. An increase in the set point pressure, however, is blocked if at least one blocking condition is met.

Claims

1. A method of operating a fuel system of an internal combustion engine in which fuel is compressed by a fuel pump and flows through at least one fuel injection device into at least one combustion chamber of the internal combustion engine, the method comprising:

actuating the fuel pump, at least periodically during a phase immediately when starting or just after starting the internal combustion engine, corresponding to an increased set point pressure; and

blocking an increase to the set point pressure if at least one blocking condition is met, wherein the blocking condition is met if a degree to which a catalytic converter assembly of the internal combustion engine is heated up at least achieves a threshold state.

2. A method according to claim 1, wherein the blocking condition is met if the set point pressure has already at least once been increased within an existing operating cycle.

3. A method according to claim 1, wherein the blocking condition is met if an actual temperature of the fuel system, especially of the fuel pump or of a fuel filter, achieves or exceeds a threshold value.

4. A method according to claim 1, wherein the blocking condition is met if a time, which has elapsed since starting the internal combustion engine achieves or exceeds a threshold value.

5. A method according to claim 1, wherein the blocking condition is met if a release of the air bag is requested in a motor vehicle in which the fuel system is installed.

6. A method according to claim 1, wherein the blocking condition is met if at least one certain error is detected in the fuel system.

7. A method according to claim 1, wherein the increased set point pressure is a function of a set point output rate and an actual supply voltage of the fuel pump.

8. A method according to claim 1, wherein a normal set point pressure is a function of a rotational speed of a crankshaft of the internal combustion engine and of a relative filling of a cylinder with air;

and wherein the increased set point pressure is dependent on an actual fuel temperature in such a way that the set point is more dramatically increased at a higher fuel temperature than at a lower fuel temperature.

9. A computer-readable storage medium encoding a computer program of instructions for executing a computer process for operating a fuel system of an internal combustion engine in which fuel is compressed by a fuel pump and flows through at least one fuel injection device into at least one combustion chamber of the internal combustion engine, said computer process comprising:

actuating the fuel pump, at least periodically during a phase immediately when starting or just after starting the internal combustion engine, corresponding to an increased set point pressure; and

blocking an increase to the set point pressure if at least one blocking condition is met, wherein the blocking condition is met if the set point pressure has already at least once been increased within an existing operating cycle.

12. The computer readable storage medium according to claim 9, wherein the blocking condition is met if a degree to which a catalytic converter assembly of the internal combustion engine is heated up at least achieves a threshold state.

13. The computer readable storage medium according to claim 9, wherein the blocking condition is met if an actual temperature of the fuel system, especially of the fuel pump or of a fuel filter, achieves or exceeds a threshold value.

14. The computer readable storage medium according to claim 9, wherein the blocking condition is met if a time, which has elapsed since starting the internal combustion engine, achieves or exceeds a threshold value.

10. An electrical storage medium for an open-loop or closed-loop control device of a fuel system of an internal combustion engine, the electrical storage medium including instructions for:

actuating a fuel pump of the fuel system, at least periodically during a phase immediately when starting or just after starting the internal combustion engine, corresponding to an increased set point pressure; and

blocking an increase to the set point pressure if at least one blocking condition is met, wherein the blocking condition is met if an actual temperature of the fuel system, including the fuel pump or of a fuel filter, achieves or exceeds a threshold value.

15. The electrical storage medium according to claim 10, wherein the blocking condition is met if a release of the air bag is requested in a motor vehicle in which the fuel system is installed.

16. The electrical storage medium according to claim 10, wherein the blocking condition is met if at least one certain error is detected in the fuel system.

17. The electrical storage medium according to claim 10, wherein the increased set point pressure is a function of a set point output rate and an actual supply voltage of the fuel pump.

11. An open-loop and/or closed-loop control device for a fuel system of an internal combustion engine, wherein the control device actuates the fuel pump, at least periodically during a phase immediately when starting or just after starting the internal combustion engine, corresponding to an increased set point pressure;

and blocks an increase to the set point pressure if at least one blocking condition is met, wherein the increased set point pressure is a function of a set point output rate and an actual supply voltage of the fuel pump.

18. The open-loop and/or closed-loop control device according to claim 11, wherein the blocking condition is met if a degree to which a catalytic converter assembly of the internal combustion engine is heated up at least achieves a threshold state.

19. The open-loop and/or closed-loop control device according to claim 11, wherein a normal set point pressure is a function of a rotational speed of a crankshaft of the internal combustion engine and of a relative filling of a cylinder with air;

and wherein the increased set point pressure is dependent on an actual fuel temperature in such a way that the set point is more dramatically increased at a higher fuel temperature than at a lower fuel temperature.