LOW PRESSURE FUEL PUMP CONTROL METHOD OF GDI ENGINE

• US 20130144507A1
• Filed: 07/17/2012
• Published: 06/06/2013
• Est. Priority Date: 12/01/2011
• Status: Abandoned Application

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group), Kia Motors Corporation (Kia Corp.)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group), Kia Motors Corporation (Kia Corp.)
• Inventors: Lee, Bum Ky
• Application Number:
  US13/551,203
• Publication Number:
  US 20130144507A1
• Time in Patent Office: Days
• US Class Current: 701/103
• CPC Class Codes: F02D 2200/0602 Fuel pressure
• CPC Class Codes: F02D 41/042 for stopping the engine
• CPC Class Codes: F02D 41/062 for starting F02D41/061 takes precedence
• CPC Class Codes: F02D 41/3082 Control of electrical fuel pumps
• CPC Class Codes: F02D 41/3854 with elements in the low pressure part, e.g. low pressure pump

Abstract

A low pressure fuel pump controlling method for a fuel feeding system of a GDI engine that includes a low pressure system and a high pressure system including controlling the low pressure fuel pump against various problems that may occur during the driving of the engine by variable control of the low pressure fuel pump of the low pressure system for the improvement of fuel efficiency of a vehicle. In various situations, the method drives the low pressure fuel pump under a relatively higher pressure than the fuel efficiency pressure.

Claims

1. A method of variable-controlling a low pressure fuel pump of a low pressure system in a fuel feeding system of a gasoline direct injection (GDI) engine, the method comprising:

driving the low pressure fuel pump at KEY ON of a vehicle when the GDI engine is stopped; and

setting a target fuel pressure of the low pressure fuel pump to a relatively higher pressure than a fuel pressure concentrated on fuel efficiency within a fuel pressure range that is made by the low pressure fuel pump.

2. The method of claim 1, wherein the target fuel pressure of the low pressure fuel pump is set according to a temperature of a coolant of the GDI engine at the KEY ON.

3. The method of claim 1, wherein the target fuel pressure of the low pressure fuel pump at cranking of the GDI engine is set to a relatively higher pressure than a fuel pressure concentrated on fuel efficiency within a fuel pressure range that is made by the low pressure fuel pump.

4. The method of claim 3, wherein the target fuel pressure of the low pressure fuel pump at the cranking is maintained for a preset time duration determined by temperature of a coolant and a soaking time.

14. The method of claim 1, wherein the relatively higher pressure within the fuel pressure range that is made by the low pressure fuel pump ranges from about 4 bar to about 6 bar.

15. The method of claim 2, wherein the relatively higher pressure within the fuel pressure range that is made by the low pressure fuel pump ranges from about 4 bar to about 6 bar.

16. The method of claim 3, wherein the relatively higher pressure within the fuel pressure range that is made by the low pressure fuel pump ranges from about 4 bar to about 6 bar.

5. A method of variable-controlling a low pressure fuel pump of a low pressure system in a fuel feeding system of a GDI engine, the method comprising:

driving the low pressure fuel pump for a preset time duration in a preset time interval at soaking when the GDI engine is cooling after KEY OFF of a vehicle.

6. The method of claim 5, wherein the low pressure fuel pump is driven continuously under a relatively higher pressure than a fuel efficiency pressure concentrated on fuel efficiency within a fuel pressure range that is made by the low pressure fuel pump, until a main relay is turned off at KEY OFF of a vehicle.

7. The method of claim 5, wherein the low pressure fuel pump is driven at a relatively higher pressure than a fuel efficiency pressure concentrated on fuel efficiency within a fuel pressure range that is made by the low pressure fuel pump for a preset time duration in a preset time interval at KEY ON of a vehicle when the GDI engine is stopped, at cranking of the GID engine, until a main relay is turned off at KEY OFF of a vehicle, and at soaking when the GDI engine is cooling after KEY OFF of the vehicle.

8. The method of claim 7, wherein the low pressure fuel pump is driven within the fuel pressure range that is made by the low pressure fuel pump even at malfunction of a high pressure system, an extreme high temperature traveling, an extreme low temperature traveling, an extreme high land traveling, or at detection of HIGH DI fuel.

9. The method of claim 8, wherein a closed circuit generation control for improving a fuel efficiency is restricted to guarantee a sufficient voltage of a batter during the driving of the low pressure fuel pump under the high pressure within the fuel pressure range that is made by the low pressure fuel pump.

10. The method of claim 5, wherein the target fuel pressure of the low pressure fuel pump at the driving the low pressure fuel pump is set to a relatively higher pressure than a fuel efficiency pressure concentrated on fuel efficiency within a fuel pressure range that is made by the low pressure fuel pump.

17. The method of claim 10, wherein the relatively higher pressure within the fuel pressure range that is made by the low pressure fuel pump ranges from about 4 bar to about 6 bar.

11. A method of variable-controlling a low pressure fuel pump of a low pressure system in a fuel feeding system of a GDI engine, the method comprising:

driving the low pressure fuel pump at a high pressure within a fuel pressure range that is made by the low pressure fuel pump in a case when at least one of situations occur, wherein the situations include malfunction of a high pressure system, an extreme high temperature traveling, an extreme low temperature traveling, an extreme high land traveling, or detection of HIGH DI (direct injection) fuel.

12. The method of claim 11, further comprising:

releasing the driving of the low pressure fuel pump at the high pressure when a corresponding situation is completed even during performance of a corresponding traveling cycle in the case of the extreme high temperature traveling, the extreme low temperature traveling, the extreme high land traveling, or the detection of HIGH DI fuel; and

driving the low pressure fuel pump continuously within the corresponding traveling cycle in the case of the malfunction of the high pressure system.

18. The method of claim 11, wherein the relatively higher pressure within the fuel pressure range that is made by the low pressure fuel pump ranges from about 4 bar to about 6 bar.

19. The method of claim 12, wherein the relatively higher pressure within the fuel pressure range that is made by the low pressure fuel pump ranges from about 4 bar to about 6 bar.

13. A method of variable-controlling a low pressure fuel pump of a low pressure system in a fuel feeding system of a GDI engine, the method comprising:

driving the low pressure fuel pump under a high pressure within a fuel pressure range that is made by the low pressure fuel pump; and

restricting a closed circuit generation control for improving a fuel efficiency to secure a sufficient voltage of a battery during the driving of the low pressure fuel pump under the high pressure.

20. The method of claim 13, wherein the relatively higher pressure within the fuel pressure range that is made by the low pressure fuel pump ranges from about 4 bar to about 6 bar.