Control device for fuel injection valve and fuel injection system

Patent metadata

Field	Value
Publication number	US-11466653-B2
Application number	US-202017104784-A
Country	US
Kind code	B2
Filing date	Nov 25, 2020
Priority date	May 31, 2018
Publication date	Oct 11, 2022
Grant date	Oct 11, 2022

Abstract

A control device controls a drive current that flows through a drive coil of a fuel injection valve that is electromagnetically driven. A control device includes a determination unit configured to determine whether a supply fuel pressure, which is a pressure of fuel supplied to the fuel injection valve, is higher than a determination pressure at which the fuel pressure is determined abnormally high; a first control unit configured to control the drive current in a first mode when the determination unit determines that the supply fuel pressure is not higher than the determination pressure; and a second control unit configured to control the drive current in a second mode that facilitates maintaining of the fuel injection valve in an open state more than in the first mode when the determination unit determines that the supply fuel pressure is higher than the determination pressure.

First claim

What is claimed is:

1. A control device configured to control a drive current that flows through a drive coil of a fuel injection valve that is configured to be electromagnetically driven, the control device comprising:
a determination unit configured to determine whether a supply fuel pressure, which is a pressure of fuel supplied to the fuel injection valve, is higher than a determination pressure at which the fuel pressure is determined abnormally high;
a first control unit configured to control the drive current in a first mode, when the determination unit determines that the supply fuel pressure is not higher than the determination pressure; and
a second control unit configured to control the drive current in a second mode that facilitates maintaining of the fuel injection valve in an open state more than in the first mode, when the determination unit determines that the supply fuel pressure is higher than the determination pressure, wherein
a voltage applied to the drive coil when the drive current is increased to a maximum value in an injection period in the second mode is higher than a voltage applied to the drive coil when the drive current is increased to a maximum value in an injection period in the first mode.

2. The control device for the fuel injection valve according to claim 1 , wherein
the second mode includes a control to continuously maintain the drive current after increasing the drive current to a maximum value in an injection period and a control to reduce the drive current from the maximum value in the injection period to a hold value and to maintain the drive current.

3. The control device for the fuel injection valve according to claim 2 , wherein
the first mode includes a control to increase the drive current to the maximum value in the injection period and subsequently to continuously decrease the drive current to the hold value and to maintain the drive current, and
the maximum value of the drive current in the injection period in the second mode is larger than the maximum value of the drive current in the injection period in the first mode.

4. A control device configured to control a drive current that flows through a drive coil of a fuel injection valve that is configured to be electromagnetically driven, the control device comprising:
a determination unit configured to determine whether a supply fuel pressure, which is a pressure of fuel supplied to the fuel injection valve, is higher than a determination pressure at which the fuel pressure is determined abnormally high;
a first control unit configured to control the drive current in a first mode, when the determination unit determines that the supply fuel pressure is not higher than the determination pressure; and
a second control unit configured to control the drive current in a second mode that facilitates maintaining of the fuel injection valve in an open state more than in the first mode, when the determination unit determines that the supply fuel pressure is higher than the determination pressure, wherein
the second mode includes a control to continuously maintain the drive current after increasing the drive current to a maximum value in an injection period and a control to reduce the drive current from the maximum value in the injection period to a hold value and to maintain the drive current,
the first mode includes a control to increase the drive current to the maximum value in the injection period and subsequently to continuously decrease the drive current to the hold value and to maintain the drive current, and
the maximum value of the drive current in the injection period in the second mode is larger than the maximum value of the drive current in the injection period in the first mode.

5. The control device for the fuel injection valve according to claim 2 , wherein
the first mode includes a control to increase the drive current to the maximum value in the injection period and subsequently to continuously decrease the drive current to the hold value and to maintain the drive current, and
the maximum value of the drive current in the injection period in the second mode is smaller than the maximum value of the drive current in the injection period in the first mode.

6. A control device configured to control a drive current that flows through a drive coil of a fuel injection valve that is configured to be electromagnetically driven, the control device comprising:
a determination unit configured to determine whether a supply fuel pressure, which is a pressure of fuel supplied to the fuel injection valve, is higher than a determination pressure at which the fuel pressure is determined abnormally high;
a first control unit configured to control the drive current in a first mode, when the determination unit determines that the supply fuel pressure is not higher than the determination pressure; and
a second control unit configured to control the drive current in a second mode that facilitates maintaining of the fuel injection valve in an open state more than in the first mode, when the determination unit determines that the supply fuel pressure is higher than the determination pressure, wherein
the second mode includes a control to continuously maintain the drive current after increasing the drive current to a maximum value in an injection period and a control to reduce the drive current from the maximum value in the injection period to a hold value and to maintain the drive current,
the first mode includes a control to increase the drive current to the maximum value in the injection period and subsequently to continuously decrease the drive current to the hold value and to maintain the drive current, and
the maximum value of the drive current in the injection period in the second mode is smaller than the maximum value of the drive current in the injection period in the first mode.

7. The control device for the fuel injection valve according to claim 2 , wherein
the second control unit is configured to set a period, in which the second control unit maintains the drive current continuously after increasing the drive current to the maximum value in the injection period, such that as a rotation speed of the engine, to which the fuel injection valve is mounted, becomes higher, the period becomes shorter.

8. The control device for the fuel injection valve according to claim 2 , wherein
the second control unit is configured to set a period, in which the second control unit maintains the drive current continuously after increasing the drive current to the maximum value in the injection period, to a period in which the fuel injection valve is stabilized in the open state.

9. The control device for the fuel injection valve according to claim 1 , wherein
the second control unit is configured to change the drive current in the second mode to the drive current in the first mode when the period in which the second control unit controls the drive current continuously in the second mode becomes longer than a predetermined period.

10. A control device configured to control a drive current that flows through a drive coil of a fuel injection valve that is configured to be electromagnetically driven, the control device comprising:
a determination unit configured to determine whether a supply fuel pressure, which is a pressure of fuel supplied to the fuel injection valve, is higher than a determination pressure at which the fuel pressure is determined abnormally high;
a first control unit configured to control the drive current in a first mode, when the determination unit determines that the supply fuel pressure is not higher than the determination pressure; and
a second control unit configured to control the drive current in

Assignees

• Denso Corp

Inventors

• Yanoto Keisuke

Classifications

• F02D2200/0602

  Fuel pressure · CPC title

• F02D2041/2006

  by using a boost capacitor · CPC title

• F02D2041/224

  Diagnosis of the fuel system · CPC title

• F02D2041/2058

  using information of the actual current value · CPC title

• F02M51/066

  the armature and the valve being allowed to move relatively to each other or not being attached to each other · CPC title