Claims
- 1. A fuel feed control system for a multi-cylinder internal combustion engine, comprising:
- fuel quantity setting means for setting a quantity of fuel to be fed at a desired fuel feeding time in an induction stroke of the internal combustion engine on the basis of inducted air quantity information detected at a desired inducted air quantity detection time before an end of the induction stroke, and
- means for feeding, at the desired fuel feeding time, fuel in the quantity set by the fuel quantity setting means;
- wherein said fuel quantity setting means is provided with inducted air estimation means for estimating information on a quantity of air, which is to be inducted during the induction stroke corresponding to the desired fuel feeding time, on the basis of a result of detection of an inducted air quantity at the desired inducted air quantity detection time, inducted air quantity information detected before the desired inducted air quantity detection time and predicted information, and
- said inducted air estimation means is provided with transient operation state detection means for detecting a transient operation state of the internal combustion engine and predicted information changing means for changing the predicted information so that, upon detection of the transient operation state of the internal combustion engine by said transient operation state detection means, the estimated quantity of inducted air and a corresponding real quantity of inducted air become closer to each other.
- 2. A fuel feed control system according to claim 1, wherein said predicted information changing means comprises means for changing the predicted information in accordance with a result of a comparison between the estimated quantity of inducted air and the corresponding real quantity of inducted air upon detection of the transient operation state of the internal combustion engine by said transient operation state detection means.
- 3. A fuel feed control system according to claim 1, wherein said predicted information changing means comprises means for setting, as an initial value of the predicted information, a value greater than a number of detections of the quantity of inducted air between the desired inducted air quantity detection time and the desired fuel feeding time when the transient operation state of the internal combustion engine is detected by said transient operation state detection means.
- 4. A fuel feed control system according to claim 1, wherein said predicted information changing means comprises means for changing the predicted information in accordance with a result of a comparison between the estimated quantity of inducted air and the corresponding real quantity of the inducted air after a value greater than a number of detections of the quantity of inducted air between the desired inducted air quantity detection time and the desired fuel feeding time has been set as an initial value of the predicted information subsequent to detection of the transient operation state of the internal combustion engine by said transient operation state detection means.
- 5. A fuel feed control system according to claim 3, wherein said predicted information changing means comprises means for setting the initial value of the predicted information in accordance with at least one of a quantity and direction of a transient change of the internal combustion engine when the value greater than the number of detections of the quantity of inducted air between the desired inducted air quantity detection time and the desired fuel feeding time is set as the initial value of the predicted information upon detection of the transient operation state of the internal combustion engine by said transient operation state detection means.
- 6. A fuel feed control system according to claim 4, wherein said predicted information changing means comprises means for setting the initial value of the predicted information in accordance with at least one of a quantity and direction of a transient change of the internal combustion engine when the value greater than the number of detections of the quantity of inducted air between the desired inducted air quantity detection time and the desired fuel feeding time is set as the initial value of the predicted information upon detection of the transient operation state of the internal combustion engine by said transient operation state detection means.
- 7. A fuel feed control system according to claim 2, wherein said predicted information changing means comprises means for changing and correcting the predicted information in a direction opposite to the direction of a preceding change and correction when the difference between the corresponding real quantity of the inducted air and the estimated quantity of inducted air becomes smaller than a predetermined positive value upon changing the predicted information in accordance with the result of a comparison between the estimated quantity of inducted air and the corresponding real quantity of inducted air subsequent to the detection of the transient operation state of the internal combustion engine by said transient operation state detection means.
- 8. A fuel feed control system according to claim 1, wherein said predicted information changing means comprises means for stepwise changing a rate of decrease of the predicted information in at least two stages upon changing the predicted information in a decreasing direction.
- 9. A fuel feed control system according to claim 1, wherein said inducted air quantity estimation means comprises:
- said transient operation state detection means;
- means for detecting a high-load operation state of the internal combustion engine;
- said predicted information changing means; and
- prediction inhibiting or low-gain setting means
- for setting the predicted information at 0 or at a predetermined low value and prohibiting the changing operation for the predicted information performed by said predicted information changing means when a high-load operation state of the internal combustion engine is detected by said high-load operation state detection means.
- 10. A fuel feed control system according to claim 2, wherein said predicted information changing means is provided with means for setting a lower limit of the predicted information so that the lower limit is varied depending on the result of the comparison between the estimated quantity of inducted air and the corresponding real quantity of inducted air, and said lower limit setting means comprises means for setting as the lower limit a value in a range not greater than a number of detections of the quantity of inducted air between the desired inducted air quantity detection time and the desired fuel feeding time.
- 11. A fuel feed control system according to claim 2, wherein said predicted information changing means is provided with means for setting an upper limit for the predicted information which varies depending on the result of the comparison between the estimated quantity of inducted air and the corresponding real quantity of inducted air.
- 12. A fuel feed control system according to claim 11, wherein said upper limit setting means sets the upper limit at different values depending on whether the internal combustion engine is in acceleration or in deceleration.
- 13. A fuel feed control system according to claim 1, wherein said inducted air estimation means estimates the inducted air quantity information at the desired fuel feeding time on the basis of the detection result of the quantity of inducted air at the desired inducted air quantity detection time and a value obtained by incorporating the predicted information into a difference between the detection result of the quantity of inducted air at the desired inducted air quantity detection time and the inducted air quantity information detected before the desired inducted air quantity detection time.
- 14. A fuel feed control system according to claim 1, wherein said inducted air estimation means estimates the inducted air quantity information during the induction stroke, corresponding to the desired fuel feeding time, on the basis of the detection result of the quantity of inducted air at the desired inducted air quantity detection time and a value obtained by incorporating the predicted information into a difference between plural pieces of information on changes in the quantity of inducted air detected before the desired inducted air quantity detection time.
- 15. A fuel feed control method for a multi-cylinder internal combustion engine, comprising:
- (a) setting a quantity of fuel to be fed at a desired fuel feeding time in an induction stroke of the internal combustion engine on the basis of inducted air quantity information detected at a desired inducted air quantity detection time before an end of the induction stroke, and
- (b) feeding, at the desired fuel feeding time, fuel in the quantity set by the step (a);
- wherein said step (a) estimates information on a quantity of air, which is to be inducted during the induction stroke corresponding to the desired fuel feeding time, on the basis of a result of detection of an inducted air quantity at the desired inducted air quantity detection time, inducted air quantity information detected before the desired inducted air quantity detection time and predicted information, and
- said step (a) includes the substeps of,
- (a1) detecting a transient operation state of the internal combustion engine, and
- (a2) changing the predicted information so that, upon detection of the transient operation state of the internal combustion engine by said step (a1), the estimated quantity of inducted air and a corresponding real quantity of inducted air become closer to each other.
- 16. A fuel feed control method according to claim 15, wherein said step (a2) changes the predicted information in accordance with a result of a comparison between the estimated quantity of inducted air and the corresponding real quantity of inducted air upon detection of the transient operation state of the internal combustion engine by said step (a1).
- 17. A fuel feed control method according to claim 15, wherein said step (a2) sets, as an initial value of the predicted information, a value greater than a number of detections of the quantity of inducted air between the desired inducted air quantity detection time and the desired fuel feeding time when the transient operation state of the internal combustion engine is detected by said step (a1).
- 18. A fuel feed control method according to claim 15, wherein said step (a2) changes the predicted information in accordance with a result of a comparison between the estimated quantity of inducted air and the corresponding real quantity of the inducted air after a value greater than a number of detections of the quantity of inducted air between the desired inducted air quantity detection time and the desired fuel feeding time has been set as an initial value of the predicted information subsequent to detection of the transient operation state of the internal combustion engine by said step (a1).
- 19. A fuel feed control method according to claim 17, wherein said step (a2) sets the initial value of the predicted information in accordance with at least one of a quantity and direction of a transient change of the internal combustion engine when the value greater than the number of detections of the quantity of inducted air between the desired inducted air quantity detection time and the desired fuel feeding time is set as the initial value of the predicted information upon detection of the transient operation state of the internal combustion engine by said step (a1).
- 20. A fuel feed control method according to claim 18, wherein said step (a2) sets the initial value of the predicted information in accordance with at least one of a quantity and direction of a transient change of the internal combustion engine when the value greater than the number of detections of the quantity of inducted air between the desired inducted air quantity detection time and the desired fuel feeding time is set as the initial value of the predicted information upon detection of the transient operation state of the internal combustion engine by said step (a1).
- 21. A fuel feed control method according to claim 16, wherein said step (a2) changes and corrects the predicted information in a direction opposite to the direction of a preceding change and correction when the difference between the corresponding real quantity of the inducted air and the estimated quantity of inducted air becomes smaller than a predetermined positive value upon changing the predicted information in accordance with the result of a comparison between the estimated quantity of inducted air and the corresponding real quantity of inducted air subsequent to the detection of the transient operation state of the internal combustion engine by said step (a1).
- 22. A fuel feed control method according to claim 15, wherein said step (a2) stepwise changes a rate of decrease of the predicted information in at least two stages upon changing the predicted information in a decreasing direction.
- 23. A fuel feed control system according to claim 15, wherein said step (a) further includes the substeps of,
- (a3) detecting a high-load operation state of the internal combustion engine;
- (a4) setting the predicted information at 0 or at a predetermined low value when a high-load operation state of the internal combustion engine is detected by said step (a3); and
- (a5) prohibiting the changing operation for the predicted information performed by said step (a2) when a high-load operation state of the internal combustion engine is detected by said step (a3).
- 24. A fuel feed control method according to claim 16, wherein said step (a2) sets a lower limit of the predicted information so that the lower limit is varied depending on the result of the comparison between the estimated quantity of inducted air and the corresponding real quantity of inducted air, and sets as the lower limit a value in a range not greater than a number of detections of the quantity of inducted air between the desired inducted air quantity detection time and the desired fuel feeding time.
- 25. A fuel feed control method according to claim 16, wherein said step (a2) sets an upper limit for the predicted information which varies depending on the result of the comparison between the estimated quantity of inducted air and the corresponding real quantity of inducted air.
- 26. A fuel feed control method according to claim 25, wherein said step (a2) sets the upper limit at different values depending on whether the internal combustion engine is an acceleration or in deceleration.
- 27. A fuel feed control method according to claim 15, wherein said step (a) estimates the inducted air quantity information at the desired fuel feeding time on the basis of the detection result of the quantity of inducted air at the desired inducted air quantity detection time and a value obtained by incorporating the predicted information into a difference between the detection result of the quantity of inducted air at the desired inducted air quantity detection time and the inducted air quantity information detected before the desired inducted air quantity detection time.
- 28. A fuel feed control method according to claim 15, wherein said step (a) estimates the inducted air quantity information during the induction stroke, including the desired fuel feeding time, on the basis of the detection result of the quantity of inducted air at the desired inducted air quantity detection time and a value obtained by incorporating the predicted information into a difference between plural pieces of information on changes in the quantity of inducted air detected before the desired inducted air quantity detection time.
Priority Claims (1)
Number |
Date |
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Kind |
6-049167 |
Mar 1994 |
JPX |
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Parent Case Info
This application is a continuation of application Ser. No. 08/405,985, filed on Mar. 17, 1995, now abandoned.
US Referenced Citations (5)
Foreign Referenced Citations (1)
Number |
Date |
Country |
419377 |
Mar 1992 |
JPX |
Non-Patent Literature Citations (2)
Entry |
English Abstract, Japanese Patent Publ. Laid Open (Kokai) No. Sho 59-15656, Jan. 26, 1984. |
Hasegawa, Shiyunpei, English Abstract of JP HEI 4-19377, Jan. 26, 1984. |
Continuations (1)
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Number |
Date |
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Parent |
405985 |
Mar 1995 |
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