Fuel injection system of an internal combustion engine, and associated pressure regulating method

Patent metadata

Field	Value
Publication number	US-9297328-B2
Application number	US-201113977819-A
Country	US
Kind code	B2
Filing date	Dec 20, 2011
Priority date	Dec 30, 2010
Publication date	Mar 29, 2016
Grant date	Mar 29, 2016

Abstract

A fuel injection system of an internal combustion engine includes a first and a second fuel pump, a leakage-prone volume flow regulating valve arranged in a fuel line between the first and the second fuel pump, and a control unit configured to actuate the first fuel pump as a function of a position of the leakage-prone volume flow regulating valve, such that the leakage-prone volume flow regulating valve serves as the sole actuating element for pressure regulation in the fuel injection system. An associated pressure regulating method is also disclosed.

First claim

The invention claimed is:

1. A fuel injection system of an internal combustion engine, comprising:
a first and a second fuel pump,
a leakage-prone volume flow regulating valve arranged in a fuel line between the first and the second fuel pump,
a fuel temperature sensor measuring a fuel temperature downstream of the first fuel pump and upstream of the second fuel pump, and
an automated control unit configured to actuate the first fuel pump as a function of a position of the leakage-prone volume flow regulating valve, a detected operating state of the internal combustion engine, and the measured fuel temperature, such that the leakage-prone volume flow regulating valve serves as the sole control element for a fuel pressure regulation operation in the fuel injection system, and
wherein the control unit operates to deactivate the first fuel pump in response to detecting the operating state of the internal combustion engine corresponds to a first predefined operating state, and
activate the first fuel pump in response to detecting the operating state of the internal combustion engine corresponds to a second predefined operating state different from the first predefined operating state.

2. The fuel injection system of claim 1 , wherein the leakage-prone volume flow regulating valve is a slide-type volume flow regulating valve.

3. The fuel injection system of claim 1 , wherein the first fuel pump is an in-tank electric pre-feed pump.

4. The fuel injection system of claim 1 , wherein the second fuel pump is a plug-in pump configured to be lubricated by engine oil of the internal combustion engine.

5. The fuel injection system of claim 1 , wherein the control unit is configured to actuate the first fuel pump as a function of a fuel pressure measured by a fuel pressure sensor.

6. A pressure regulating method for a fuel injection system comprising a first and a second fuel pump, a leakage-prone volume flow regulating valve arranged in a fuel line between the first and the second fuel pump, and a control unit configured to actuate the first fuel pump, the pressure regulating method comprising:
detecting a position of the leakage-prone volume flow regulating valve,
detecting a fuel temperature downstream of the first fuel pump and upstream of the second fuel pump,
detecting an operating state of the internal combustion engine, and
actuating the first fuel pump as a function of the detected position of the leakage-prone volume flow regulating valve, the detected operating state of the internal combustion engine, and the detected fuel temperature, wherein the leakage-prone volume flow regulating valve serves as the sole control element for a fuel pressure regulation operation in the fuel injection system, and
wherein the control unit operates to deactivate the first fuel pump in response to detecting the operating state of the internal combustion engine corresponds to a first predefined operating state, and
activate the first fuel pump in response to detecting the operating state of the internal combustion engine corresponds to a second predefined operating state different from the first predefined operating state.

7. The pressure regulating method of claim 6 , wherein the actuation of the first fuel pump comprises time-dependent toggle switching.

8. The pressure regulating method of claim 6 , further comprising:
detecting a fuel pressure downstream of the second fuel pump, and
wherein the function used to actuate the first fuel pump is further based on the detected fuel pressure.

9. The pressure regulating method of claim 8 , comprising:
deactivating the first fuel pump in response to detecting an overshoot of a first predefined pressure threshold value, and
activating the first fuel pump in response to detecting an undershoot of a second predefined pressure threshold value different than the first predefined pressure threshold value.

10. A control unit of a fuel injection system of a motor vehicle, the control unit being configured to perform a pressure regulating method including:
detect an operating state of the internal combustion engine; and
actuate a first fuel pump of the fuel injection system as a function of the detected operating state of the internal combustion engine, a position of a leakage-prone volume flow regulating valve arranged in a fuel line between the first fuel pump and a second fuel pump, and a fuel pressure measured downstream of the first fuel pump and upstream of the second fuel pump,
such that the leakage-prone volume flow regulating valve serves as the sole control element for a fuel pressure regulation operation of the fuel injection system, and
wherein the control unit operates to deactivate the first fuel pump in response to detecting the operating state of the internal combustion engine corresponds to a first predefined operating state, and
activate the first fuel pump in response to detecting the operating state of the internal combustion engine corresponds to a second predefined operating state different from the first predefined operating state.

11. The fuel injection system control unit of claim 10 , wherein the control unit is configured to actuate the first fuel pump by time-dependent toggle switching.

12. The fuel injection system control unit of claim 10 , wherein the control unit is configured to detect a fuel pressure downstream of the second fuel pump, and actuate the first fuel pump as a function of the detected fuel pressure.

13. The fuel injection system control unit of claim 12 , wherein the control unit is configured to:
deactivate the first fuel pump in response to detecting an overshoot of a first predefined pressure threshold value, and
activate a first fuel pump in response to detecting an undershoot of a second predefined pressure threshold value different than the first predefined pressure threshold value.

Assignees

• Klesse Christoph
• Riepl Hans
• Stapf Wolfgang
• Ritsch Tobias
• Lingener Uwe
• Continental Automotive Gmbh

Inventors

• Klesse Christoph
• Riepl Hans
• Stapf Wolfgang
• Ritsch Tobias
• Lingener Uwe

Classifications

• F02D2200/0602

  Fuel pressure · CPC title

• F02D41/3005 Primary

  Details not otherwise provided for · CPC title

• F02D41/3854 Primary

  with elements in the low pressure part, e.g. low pressure pump · CPC title