US 7,007,670 B2Granted

Fuel injection device

AssigneeBosch Automotive Systems Corporation

InventorsKenji Okamoto, Akira Kunishima

Life of this patent

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Abstract

In a state in which a high-pressure control solenoid valve is driven to control the pressure in a common rail (refer to Step S100), when the pressure in the common rail exceeds a predetermined value (refer to Step S104), a driving current determined by a prescribed value map that defines the correlation between the pressure in the common rail and the driving current of the high-pressure control solenoid valve is corrected based on an actual pressure in the common rail and the driving current of the high-pressure control solenoid valve at the actual pressure (refer to Steps S106, 108, S110, 112), and the corrected driving current is passed to the high-pressure control solenoid valve, thereby ensuring appropriate and stable injection control even when there exists a variation in operational characteristics among pressure control valves.

Claims4

Dependent claims

An operation control method using a fuel injection device, comprising:

pressurizing fuel from a fuel tank using a high-pressure pump so that the pressurized fuel is stored in a common rail;
supplying the pressurized fuel stored in the common rail to an injection nozzle connected to the common rail;
and
controlling the pressure of the pressurized fuel stored in the common rail by using a low-pressure control solenoid valve upstream of the high-pressure pump, and by using a high-pressure control solenoid valve downstream of the high-pressure pump, the low-pressure control solenoid valve and the high-pressure control solenoid valve being selectively feedback-controlled to control the pressure of the pressurized fuel stored in the common rail;
wherein, when a pressure in the common rail exceeds a predetermined value and the high-pressure control solenoid valve is being used to control the pressure of the pressurized fuel stored in the common rail, said controlling comprises:
determining a driving current of the high-pressure control solenoid valve using a prescribed value map defining a correlation between the pressure of the pressurized fuel stored in the common rail and the driving current of the high-pressure control solenoid valve;
correcting the determined driving current of the high-pressure control solenoid valve based on an actual pressure in the common rail and the driving current of the high-pressure control solenoid valve at the actual pressure;
and
supplying the corrected driving current to the high-pressure control solenoid valve.

6 more elements

A fuel injection device comprising:

a fuel tank for storing fuel;
a common rail for storing pressurized fuel;
a high-pressure pump connected to said fuel tank and said common rail, said high-pressure tank being operable to pressurize fuel from said fuel tank so that the pressurized fuel is stored in said common rail;
an injection nozzle connected to said common rail so as to receive the pressurized fuel from said common rail;
a low-pressure control solenoid valve upstream of said high-pressure pump;
a high-pressure control solenoid valve downstream of said high-pressure pump;
and
a control unit for selectively feedback-controlling said low-pressure control solenoid valve and said high-pressure control solenoid valve to control the pressure of the pressurized fuel stored in said common rail, said control unit having a prescribed value map stored therein, said prescribed value map defining a correlation between the pressure in said common rail and a driving current of said high-pressure control solenoid valve;
wherein, when said control unit selectively feedback-controls said high-pressure control solenoid valve, said control unit is operable to:
determine a driving current of said high-pressure control solenoid valve for a desired pressure in said common rail based on said prescribed value map;
supply the determined driving current to said high-pressure control solenoid valve until the pressure in said common rail is judged to exceed a predetermined variation amount;
when the pressure in said common rail is judged to exceed the predetermined variation amount, correct the driving current determined using the prescribed value map based on an actual pressure in said common rail and the driving current of said high-pressure control solenoid value at the actual pressure;
and
pass the corrected driving current to said high-pressure control solenoid value.

11 more elements

Dependencies are inferred from the claim text.

Facts

Application: 11/002,058Filed 3 Dec 2004 · division
Priority: JP 2001-14633716 May 2001
Published: US 2005/0115533 A12 Jun 2005
Granted: 7 Mar 2006
Term ends: Not estimatedThe source records don’t support an estimate.

Classification12 codes

F02D 41/3863
Controlling the fuel pressure: by controlling the flow out of the common rail, e.g. using pressure relief valves
F02D 41/062
For engine starting or warming up: for starting
F02D 41/20
Electrical control of supply of combustible mixture or its constituents: output circuits, e.g. for controlling currents in command coils
F02D 41/2464
Characterised by what is learned or calibrated: characteristics of actuators

Family

Application10/677,268Parent of this division · filed 3 Oct 2003
US 2005/0115533 A1Pre-grant publication · published 2 Jun 2005
US 6,912,983 B2Parent of this division
US 2004/0069278 A1Published application
US 7,007,670 B2This patent

From the US filing history. Foreign family members aren’t listed.