Fuel injection control device for internal combustion engine

Patent metadata

Field	Value
Publication number	US-10125730-B2
Application number	US-201615568248-A
Country	US
Kind code	B2
Filing date	Mar 30, 2016
Priority date	Apr 24, 2015
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

An ECU as a fuel injection control device includes: an injector control part that energizes a magnetic circuit of a fuel injector by a specified injection pulse to thereby open the fuel injector and that energizes the magnetic circuit by a specified energization pulse within a range in which a needle valve of the fuel injector is not driven; and a storage part that stores information relating to a behavior of a drive voltage (minus terminal voltage) of the fuel injector when the magnetic circuit is energized by the injector control part by the specified energization pulse.

First claim

The invention claimed is:

1. A fuel injection control device for an internal combustion engine which is provided with a fuel injector of an electromagnetic drive, the fuel injection control device comprising:
a control part that energizes a magnetic circuit of the fuel injector by a specified injection pulse to open the fuel injector and that energizes the magnetic circuit by a specified energization pulse within a range in which a valve body of the fuel injector is not driven;
a storage part that stores information relating to a behavior of a drive voltage of the fuel injector when the magnetic circuit is energized by the control part by the specified energization pulse; and
a calculation part that measures the behavior of the drive voltage of the fuel injector when the magnetic circuit is energized by the control part by the specified energization pulse and that calculates a magnetic circuit variation value showing a degree of variation in the behavior by an effect of the magnetic circuit on the basis of the measured behavior of the drive voltage, wherein
the storage part stores the magnetic circuit variation value calculated by the calculation part as the information relating to the behavior of the drive voltage, and
when the control part opens the fuel injector, the control part uses the specified injection pulse which is corrected on the basis of the magnetic circuit variation value stored in the storage part.

2. The fuel injection control device for an internal combustion engine according to claim 1 , wherein
the drive voltage is a minus terminal voltage of the fuel injector.

3. The fuel injection control device for an internal combustion engine according to claim 1 , wherein
the specified energization pulse is set in a range in which the valve body of the fuel injector is not driven by regulating a target current value or an energization pulse width thereof.

4. The fuel injection control device for an internal combustion engine according to claim 3 , wherein
at least one of the target current value and the energization pulse width of the specified energization pulse is changed according to an operating state of the internal combustion engine.

5. The fuel injection control device for an internal combustion engine according to claim 4 , wherein
the target current value of the specified energization pulse is set higher as a control fuel pressure of the internal combustion engine is higher and is set lower as the control fuel pressure of the internal combustion engine is lower.

6. The fuel injection control device for an internal combustion engine according to claim 1 , wherein
the information relating to the behavior of the drive voltage is calculated from a value, which is obtained by smoothing the drive voltage by a filter when the magnetic circuit is energized by the control part by the specified energization pulse.

7. The fuel injection control device for an internal combustion engine according to claim 1 , wherein
when the control part opens the fuel injector, the control part corrects an energization time of the fuel injector on the basis of the information which relates to the behavior of the drive voltage and is stored in the storage part.

8. The fuel injection control device for an internal combustion engine according to claim 1 , wherein
when the control part opens the fuel injector, the control part corrects a detection value of the drive voltage on the basis of the information which relates to the behavior of the drive voltage and is stored in the storage part, and the control part sets the specified injection pulse on the basis of the corrected detection value.

9. The fuel injection control device for an internal combustion engine according to claim 1 , wherein
the storage part stores information relating to a behavior of a drive voltage after the specified energization pulse is turned off.

10. A fuel injection control device for an internal combustion engine which is provided with a fuel injector of an electromagnetic drive, the fuel injection control device comprising:
a control part that energizes a magnetic circuit of the fuel injector by a specified injection pulse to open fuel injector and that energizes the magnetic circuit by a specified energization pulse within a range in which a valve body of the fuel injector is not driven; and
a storage part that stores information relating to a behavior of a drive voltage of the fuel injector when the magnetic circuit is energized by the control part by the specified energization pulse:
wherein the information relating to the behavior of the drive voltage includes a variance between a drive-voltage-behavior value calculated from the measured behavior of the drive voltage and an average value the individual drive-voltage-behavior values of the plurality of fuel injectors provided in the internal combustion engine.

11. The fuel injection control device for an internal combustion engine according to claim 10 , wherein
the variance is a ratio between both values.

12. The fuel injection control device for an internal combustion engine according to claim 10 , wherein
the variance is a difference between both values.

13. The fuel injection control device for an internal combustion engine according to claim 10 , wherein
the drive-voltage-behavior value is an index using time as a unit.

14. The fuel injection control device for an internal combustion engine according to claim 10 , wherein
the drive-voltage-behavior value is an index using voltage as a unit.

15. A fuel injection control device for an internal combustion engine which is provided with a fuel injector of an electromagnetic drive, the fuel injection control device comprising:
a control part that energizes a magnetic circuit of the fuel injector by a specified injection pulse to open the fuel injector and that energizes the magnetic circuit by a specified energization pulse within a range in which a valve body of the fuel injector is not driven; and
a storage part that stores information relating to a behavior of a drive voltage of the fuel injector when the magnetic circuit is energized by the control part by the specified energization pulse, wherein
the control part energizes the magnetic circuit by the specified energization pulse at the time of an operating range in which the fuel injector does not inject fuel; and
the control part energizes the magnetic circuit by the specified energization pulse in a fuel-cut operation while the internal combustion engine is being driven.

16. A fuel injection control device for an internal combustion engine which is provided with a fuel injector of an electromagnetic drive, the fuel injection control device comprising:
a control part that energizes a magnetic circuit of the fuel injector by a specified injection pulse to open the fuel injector and that energizes the magnetic circuit by a specified energization pulse within a range in which a valve body of the fuel injector is not driven; and
a storage part that stores information relating to a behavior of a drive voltage of the fuel injector when the magnetic circuit is energized by the control part by the specified energization pulse;
wherein the information relating to the behavior of the drive voltage includes a variance between a drive-voltage-behavior value calculated from the measured behavior of the drive voltage and a base value relating to the behavior of the drive voltage.

17. The fuel injection control device for an internal combustion engine according to claim 16 , wherein
the base value is set in advance.

Assignees

• Denso Corp

Inventors

• Yanoto Keisuke

Classifications

• F02D41/20 Primary

  Output circuits, e.g. for controlling currents in command coils · CPC title

• F02D2041/1432

  the system including a filter, e.g. a low pass or high pass filter · CPC title

• F02D41/2425

  Particular ways of programming the data · CPC title

• F02D2041/2048

  said control involving a limitation, e.g. applying current or voltage limits · CPC title

• F02D41/1401

  characterised by the control or regulation method (F02D41/1473, F02D41/1477 take precedence) · CPC title