DEVICE AND METHOD FOR CONTROLLING IGNITION TIMING OF INTERNAL COMBUSTION ENGINE

Abstract

An engine ECU executes a program including a step of, when an absolute value of a difference between a determination value V(KX) used for determining presence or absence of knocking and a maximum value V(MAX) of magnitude value LOG(V), which is obtained by logarithmically converting a magnitude V detected based on a signal sent from a knock sensor, is greater than the product of a standard deviation σ and a coefficient U(3) in a frequency distribution of magnitude values LOG(V) for N cycle(s), setting a value obtained by adding the product of the standard deviation σ and the coefficient U(3) to the maximum value V(MAX) of the magnitude value LOG(V) as the determination value V(KX).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic configuration diagram of an engine controlled by an engine ECU which is an ignition timing control device according to a first embodiment of the present invention;

FIG. 2 is a chart showing frequency bands of vibration generated in the engine at the time of knocking;

FIG. 3 is a control block diagram showing the engine ECU in FIG. 1;

FIG. 4 is a chart showing a waveform of vibration in the engine;

FIG. 5 is a chart showing a knock waveform model stored in ROM of the engine ECU;

FIG. 6 is a chart for comparing the vibration waveform with the knock waveform model;

FIG. 7 is a chart showing a map of a determination value V(KX) stored in the ROM or SRAM of the engine ECU;

FIG. 8 is a chart (No. 1) showing frequency distribution of magnitude values LOG(V);

FIG. 9 is a chart (No. 2) showing frequency distribution of magnitude values LOG(V);

FIG. 10 is a chart (No. 3) showing frequency distribution of magnitude values LOG(V);

FIG. 11 is a chart (No. 4) showing frequency distribution of magnitude values LOG(V);

FIG. 12 is a chart showing magnitude values LOG(V) used for forming the frequency distribution of the magnitude values LOG(V);

FIG. 13 is a flowchart (No. 1) showing a control structure of the program executed by the engine ECU which is the ignition timing control device according to the first embodiment of the present invention;

FIG. 14 is a flowchart (No. 2) showing the control structure of the program executed by the engine ECU which is the ignition timing control device according to the first embodiment of the present invention;

FIG. 15 is a chart showing frequency distribution of magnitude values LOG(V) and determination value V(KX);

FIG. 16 is a chart (No. 1) showing an integrated value at the time of knocking and an integrated value by noise; and

FIG. 17 is a chart (No. 2) showing an integrated value at the time of knocking and an integrated value by noise.

Claims

1. A device for controlling ignition timing of an internal combustion engine, comprising: a knock sensor detecting magnitude of vibration occurring in said internal combustion engine; andan operation unit connected to said knock sensor, whereinsaid operation unit calculates knock magnitude related to magnitude of vibration due to knocking, based on the magnitude of vibration occurring in said internal combustion engine,said operation unit controls ignition timing of said internal combustion engine (100), based on a result of comparison between said knock magnitude and a predetermined determination value,said operation unit corrects said determination value, based on an occurrence frequency of knocking, andsaid operation unit sets said determination value, when a difference between the magnitude of vibration occurring in said internal combustion engine and said determination value is greater than a predetermined value, to a value determined in accordance with the magnitude of vibration occurring in said internal combustion engine.

2. The device for controlling ignition timing of the internal combustion engine according to claim 1, wherein said operation unit sets said determination value, when a difference between a maximum value of the magnitudes of vibration occurring in said internal combustion engine and said determination value is greater than said predetermined value, to a value determined in accordance with the magnitude of vibration occurring in said internal combustion engine.

3. The device for controlling ignition timing of the internal combustion engine according to claim 2, wherein said operation unit sets said determination value to a value obtained by adding said predetermined value to the maximum value of the magnitudes of vibration occurring in said internal combustion engine.

4. A device for controlling ignition timing of an internal combustion engine, comprising: a knock sensor detecting magnitude of vibration occurring in said internal combustion engine; andan operation unit connected to said knock sensor, whereinsaid operation unit calculates knock magnitude related to magnitude of vibration due to knocking, based on the magnitude of vibration occurring in said internal combustion engine,said operation unit controls ignition timing of said internal combustion engine, based on a result of comparison between said knock magnitude and a predetermined determination value,said operation unit corrects said determination value, based on an occurrence frequency of knocking, andwhen a difference between the magnitude of vibration occurring in said internal combustion engine and said determination value is greater than a predetermined value, said operation unit corrects said determination value by a greater amount than when the difference is smaller.

5. The device for controlling ignition timing of the internal combustion engine according to claim 4, wherein when a difference between a maximum value of the magnitudes of vibration occurring in said internal combustion engine and said determination value is greater than said predetermined value, said operation unit corrects said determination value by a greater amount than when the difference is smaller.

6. The device for controlling ignition timing of the internal combustion engine according to claim 5, wherein said operation unit corrects said determination value by a greater amount as a difference between a maximum value of the magnitudes of vibration occurring in said internal combustion engine and said determination value is greater.

7. A method of controlling ignition timing of an internal combustion engine, comprising the steps of: detecting magnitude of vibration occurring in said internal combustion engine;calculating knock magnitude related to magnitude of vibration due to knocking, based on the magnitude of vibration occurring in said internal combustion engine,controlling ignition timing of said internal combustion engine, based on a result of comparison between said knock magnitude and a predetermined determination value;correcting said determination value, based on an occurrence frequency of knocking; andsetting said determination value, when a difference between the magnitude of vibration occurring in said internal combustion engine and said determination value is greater than a predetermined value, to a value determined in accordance with the magnitude of vibration occurring in said internal combustion engine.

8. The method of controlling ignition timing of the internal combustion engine according to claim 7, wherein said step of setting said determination value includes a step of setting said determination value, when a difference between a maximum value of the magnitudes of vibration occurring in said internal combustion engine and said determination value is greater than said predetermined value, to a value determined in accordance with the magnitude of vibration occurring in said internal combustion engine.

9. The device for controlling ignition timing of the internal combustion engine according to claim 8, wherein said step of setting said determination value includes a step of setting said determination value to a value obtained by adding said predetermined value to the maximum value of the magnitudes of vibration occurring in said internal combustion engine.

10. A method of controlling ignition timing of an internal combustion engine, comprising the steps of: detecting magnitude of vibration occurring in said internal combustion engine;calculating knock magnitude related to magnitude of vibration due to knocking, based on the magnitude of vibration occurring in said internal combustion engine;controlling ignition timing of said internal combustion engine, based on a result of comparison between said knock magnitude and a predetermined determination value; andcorrecting said determination value, based on an occurrence frequency of knocking, whereinsaid step of correcting said determination value includes a step of, when a difference between the magnitude of vibration occurring in said internal combustion engine and said determination value is greater than a predetermined value, correcting said determination value by a greater amount than when the difference is smaller.

11. The method of controlling ignition timing of the internal combustion engine according to claim 10, wherein said step of correcting said determination value includes a step of, when a difference between a maximum value of the magnitudes of vibration occurring in said internal combustion engine and said determination value is greater than said predetermined value, correcting said determination value by a greater amount than when the difference is smaller.

12. The method of controlling ignition timing of the internal combustion engine according to claim 11, wherein said step of correcting said determination value includes a step of correcting said determination value by a greater amount as a difference between a maximum value of the magnitudes of vibration occurring in said internal combustion engine and said determination value is greater.

13. A device for controlling ignition timing of an internal combustion engine, comprising: means for detecting magnitude of vibration occurring in said internal combustion engine;means for calculating knock magnitude related to magnitude of vibration due to knocking, based on the magnitude of vibration occurring in said internal combustion engine;means for controlling ignition timing of said internal combustion engine, based on a result of comparison between said knock magnitude and a predetermined determination value;means for correcting said determination value, based on an occurrence frequency of knocking; andsetting means for setting said determination value, when a difference between the magnitude of vibration occurring in said internal combustion engine and said determination value is greater than a predetermined value, to a value determined in accordance with the magnitude of vibration occurring in said internal combustion engine.

14. The device for controlling ignition timing of the internal combustion engine according to claim 13, wherein said setting means includes means for setting said determination value, when a difference between a maximum value of the magnitudes of vibration occurring in said internal combustion engine and said determination value is greater than said predetermined value, to a value determined in accordance with the magnitude of vibration occurring in said internal combustion engine.

15. The device for controlling ignition timing of the internal combustion engine according to claim 14, wherein said setting means includes means for setting said determination value to a value obtained by adding said predetermined value to the maximum value of the magnitudes of vibration occurring in said internal combustion engine.

16. A device for controlling ignition timing of an internal combustion engine, comprising: means for detecting magnitude of vibration occurring in said internal combustion engine;means for calculating knock magnitude related to magnitude of vibration due to knocking, based on the magnitude of vibration occurring in said internal combustion engine,means for controlling ignition timing of said internal combustion engine, based on a result of comparison between said knock magnitude and a predetermined determination value; andcorrecting means for correcting said determination value, based on an occurrence frequency of knocking, whereinsaid correcting means includes means for, when a difference between the magnitude of vibration occurring in said internal combustion engine and said determination value is greater than a predetermined value, correcting said determination value by a greater amount than when the difference is smaller.

17. The device for controlling ignition timing of the internal combustion engine according to claim 16, wherein said correcting means includes means for, when a difference between a maximum value of the magnitudes of vibration occurring in said internal combustion engine and said determination value is greater than said predetermined value, correcting said determination value by a greater amount than when the difference is smaller.

18. The device for controlling ignition timing of the internal combustion engine according to claim 17, wherein said correcting means includes means for correcting said determination value by a greater amount as a difference between a maximum value of the magnitudes of vibration occurring in said internal combustion engine and said determination value is greater.