Control system for controlling internal combustion engine

• US 6,116,213 A
• Filed: 04/24/1998
• Issued: 09/12/2000
• Est. Priority Date: 04/25/1997
• Status: Expired due to Term

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Ueno, Masaki, Akazaki, Shusuke, Satoh, Tadashi, Yasui, Yuji, Iwaki, Yoshihisa
• Primary Examiner(s): Dolinar, Andrew M.
• Application Number:
  US09/063,732
• Time in Patent Office: 872 Days
• Field of Search: 123/339.11, 60/284
• US Class Current: 123/339.11
• CPC Class Codes: F02D 31/003 for idle speed control
• CPC Class Codes: F02D 41/024 to increase temperature of the exhaust gas treating apparatus
• CPC Class Codes: F02D 41/067 with control of the choke non electronic control of choke see F02M1/10
• CPC Class Codes: F02P 5/1506 with particular means during starting
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A control system for controlling an internal combustion engine which discharge exhaust gases through an emission purifier includes a controller which increases the quantity of intake air drawn into the internal combustion engine while the internal combustion engine is idling after the internal combustion engine has started to operate, to a level which is greater by a predetermined increase than the quantity of intake air drawn into the internal combustion engine while the internal combustion engine is idling normally. The controller also generates a command value for ignition timing of the internal combustion engine according to a feedback control process to converge the rotational speed of the internal combustion engine toward a predetermined target rotational speed, and controlling the ignition timing of the internal combustion engine based on the generated command value thereby to retard the ignition timing. The controller establishes the target rotational speed by changing the target rotational speed from a preset rotational speed toward a predetermined idling speed after the rotational speed of the internal combustion engine has reached the preset rotational speed which is higher than the idling speed after the quantity of intake air drawn into the internal combustion engine has started being increased.

Claims

1. A control system for controlling an internal combustion engine which discharges exhaust gases through an emission purifier, comprising:

intake air quantity control means for increasing the quantity of intake air drawn into the internal combustion engine while the internal combustion engine is idling for quickly activating the emission purifier after the internal combustion engine has started to operate, to a level which is greater by a predetermined increase than the quantity of intake air drawn into the internal combustion engine while the internal combustion engine is idling normally;

means for establishing the predetermined increase depending on the engine temperature of the internal combustion engine; and

ignition timing control means for generating a command value for ignition timing of the internal combustion engine according to a feedback control process to converge the rotational speed of the internal combustion engine toward a predetermined target rotational speed which varies in accordance with predetermined after start engine conditions, and for controlling the ignition timing of the internal combustion engine based on the generated command value thereby to retard the ignition timing.

2. A control system according to claim 1, further comprising target rotational speed setting means for establishing said target rotational speed by changing the target rotational speed from a preset rotational speed toward a predetermined idling speed after the rotational speed of the internal combustion engine has reached said preset rotational speed which is higher than said idling speed after the quantity of intake air drawn into the internal combustion engine has started being increased by said intake air quantity control means.

3. A control system according to claim 1, wherein said intake air quantity control means comprises means for increasing said predetermined increase progressively with time immediately after the quantity of intake air drawn into the internal combustion engine has started being increased.

4. A control system according to claim 1, wherein said intake air quantity control means comprises means for reducing said predetermined increase progressively with time upon elapse of a predetermined time after the quantity of intake air drawn into the internal combustion engine has started being increased.

5. A control system according to claim 1, 2, 3 or 4, wherein said intake air quantity control means comprises means for correcting said predetermined increase so as to reduce the quantity of intake air when said command value for ignition timing generated by said ignition timing control means according to the feedback control process becomes more retarded than a predetermined threshold, which is established in a retarded range, within an allowable range of ignition timing in which said internal combustion engine can operate normally.

6. A control system according to claim 5, wherein said intake air quantity control means comprises means for progressively increasing a corrective quantity by which said predetermined increase is corrected so as to reduce the quantity of intake air, when said command value for ignition timing generated by said ignition timing control means according to the feedback control process is more retarded than said predetermined threshold.

7. A control system according to claim 6, wherein said intake air quantity control means comprises means for increasing said corrective quantity in each control cycle by a predetermined value established depending on a warmed-up state of the internal combustion engine, when said corrective quantity by which said predetermined increase is corrected so as to reduce the quantity of intake air is progressively increased.

8. A control system according to claim 6, wherein said intake air quantity control means comprises means for holding said corrective quantity by which said predetermined increase is corrected so as to reduce the quantity of intake air, to a present corrective quantity when said command value for ignition timing generated by said ignition timing control means according to the feedback control process is changed so as to be more advanced than said predetermined threshold, when said predetermined increase is corrected so as to reduce the quantity of intake air.

9. A control system according to claim 5, wherein said predetermined threshold is more advanced than a retarded limit of the allowable range of ignition timing.

10. A control system according to claim 5, wherein said ignition timing control means comprises means for generating the command value for ignition timing of the internal combustion engine according to a proportional plus integral control process as said feedback control process, and controlling the ignition timing of the internal combustion engine with a retarded limit of the allowable range of ignition timing and holding the value of an integral term of the proportional plus integral control process to a present value when the generated command value becomes more retarded than said retarded limit of the allowable range of ignition timing.

11. A control system according to claim 1, further comprising decision means for deciding whether or not the increasing of the quantity of intake air with said intake air quantity control means and the controlling of the ignition timing of the internal combustion engine with said ignition timing control means are to be canceled, based on an operating state of the internal combustion engine, wherein said intake air quantity control means and said ignition timing control means are disabled if the increasing of the quantity of intake air with said intake air quantity control means and the controlling of the ignition timing of the internal combustion engine with said ignition timing control means are to be canceled as decided by said decision means.

12. A control system according to claim 11, wherein said decision means comprises means for deciding that the increasing of the quantity of intake air with said intake air quantity control means and the controlling of the ignition timing of the internal combustion engine with said ignition timing control means are to be canceled, if at least one of a load, a rotational speed, and an engine temperature of said internal combustion engine, as said operating state, satisfies a predetermined condition.

13. A control system according to claim 1, further comprising decision means for deciding whether or not the increasing of the quantity of intake air with said intake air quantity control means and the controlling of the ignition timing of the internal combustion engine with said ignition timing control means are to be canceled, based on an elapsed time in which the quantity of intake air is increased by said intake air quantity control means, wherein said intake air quantity control means and said ignition timing control means are disabled if the increasing of the quantity of intake air with said intake air quantity control means and the controlling of the ignition timing of the internal combustion engine with said ignition timing control means are to be canceled as decided by said decision means.

14. A control system according to claim 13, wherein said decision means comprises means for deciding that the increasing of the quantity of intake air with said intake air quantity control means and the controlling of the ignition timing of the internal combustion engine with said ignition timing control means are to be canceled, if said elapsed time exceeds a predetermined time.

15. A control system according to claim 11 or 13, wherein said intake air quantity control means comprises means for immediately stopping increasing the quantity of intake air when the increasing of the quantity of intake air is to be canceled as decided by said decision means, and said ignition timing control means comprises means for progressively advancing the ignition timing which has been retarded according to the feedback control process when the controlling of the ignition timing is to be canceled as decided by said decision means.

16. A control system for controlling an internal combustion engine which discharges exhaust gases through an emission purifier, comprising:

intake air quantity control means for increasing the quantity of intake air drawn into the internal combustion engine while the internal combustion engine is idling for quickly activating the emission purifier after the internal combustion engine has started to operate, to a level which is greater by a predetermined increase than the quantity of intake air drawn into the internal combustion engine while the internal combustion engine is idling normally;

means for establishing the predetermined increase depending on the engine temperature of the internal combustion engine; and

ignition timing control means for generating a command value for ignition timing of the internal combustion engine according to a feedback control process to converge the rotational speed of the internal combustion engine toward a predetermined target rotational speed, and for controlling the ignition timing of the internal combustion engine based on the generated command value thereby to retard the ignition timing,

wherein said intake air quantity control means comprises means for correcting said predetermined increase so as to reduce the quantity of intake air when said command value for ignition timing generated by said ignition timing generated by said ignition timing control means according to the feedback control process becomes more retarded than a predetermined threshold, which is established in a retarded range, within an allowable range of ignition timing in which said internal combustion engine can operate normally,

wherein said intake air quantity control means comprises means for progressively increasing a corrective quantity by which said predetermined increase is corrected so as to reduce the quantity of intake air, when said command value for ignition timing generated by said ignition timing control means according to the feedback control process is more retarded than said predetermined threshold, and

wherein said intake air quantity control means comprises means for holding said corrective quantity by which said predetermined increase is corrected so as to reduce the quantity of intake air, to a present corrective quantity when said command value for ignition timing generated by said ignition timing control means according to the feedback control process is changed so as to be more advanced than said predetermined threshold, when said predetermined increase is corrected so as to reduce the quantity of intake air.

17. A control system for controlling an internal combustion engine which discharges exhaust gases through an emission purifier, comprising:

intake air quantity control means for increasing the quantity of intake air drawn into the internal combustion engine while the internal combustion engine is idling for quickly activating the emission purifier after the internal combustion engine has started to operate, to a level which is greater by a predetermined increase than the quantity of intake air drawn into the internal combustion engine while the internal combustion engine is idling normally;

means for establishing the predetermined increase depending on the engine temperature of the internal combustion engine; and

ignition timing control means for generating a command value for ignition timing of the internal combustion engine according to a feedback control process to converge the rotational speed of the internal combustion engine toward a predetermined target rotational speed, and for controlling the ignition timing of the internal combustion engine based on the generated command value thereby to retard the ignition timing,

wherein said intake air quantity control means comprises means for correcting said predetermined increase so as to reduce the quantity of intake air when said command value for ignition timing generated by said ignition timing control means according to the feedback control process becomes more retarded than a predetermined threshold, which is established in a retarded range, within an allowable range of ignition timing in which said internal combustion engine can operate normally, and

wherein said ignition timing control means comprises means for generating the command value for ignition timing of the internal combustion engine according to a proportional plus integral control process as said feedback control process, and controlling the ignition timing of the internal combustion engine with a retarded limit of the allowable range of ignition timing and holding the value of an integral term of the proportional plus integral control process to a present value when the generated command value becomes more retarded than said retarded limit of the allowable range of ignition timing.

18. A control system for controlling an internal combustion engine which discharges exhaust gases through an emission purifier, comprising:

intake air quantity control means for increasing the quantity of intake air drawn into the internal combustion engine while the internal combustion engine is idling for quickly activating the emission purifier after the internal combustion engine has started to operate, to a level which is greater by a predetermined increase than the quantity of intake air drawn into the internal combustion engine while the internal combustion engine is idling normally;

means for establishing the predetermined increase depending on the engine temperature of the internal combustion engine;

ignition timing control means for generating a command value for ignition timing of the internal combustion engine according to a feedback control process to converge the rotational speed of the internal combustion engine toward a predetermined target rotational speed, and for controlling the ignition timing of the internal combustion engine based on the generated command value thereby to retard the ignition timing, and

decision means for deciding whether or not the increasing of the quantity of intake air with said intake air quantity control means and the controlling of the ignition timing of the internal combustion engine with said ignition timing control means are to be canceled, based on an operating state of the internal combustion engine, wherein said intake air quantity control means and said ignition timing control means are disabled if the increasing of the quantity of intake air with said intake air quantity control means and the controlling of the ignition timing of the internal combustion engine with said ignition timing control means are to be canceled as decided by said decision means, and

wherein said intake air quantity control means comprises means for immediately stopping increasing the quantity of intake air when the increasing of the quantity of intake air is to be canceled as decided by said decision means, and said ignition timing control means comprises means for progressively advancing the ignition timing which has been retarded according to the feedback control process when the controlling of the ignition timing is to be canceled as decided by said decision means.

19. A control system for controlling an internal combustion engine which discharges exhaust gases through an emission purifier, comprising:

intake air quantity control means for increasing the quantity of intake air drawn into the internal combustion engine while the internal combustion engine is idling for quickly activating the emission purifier after the internal combustion engine has started to operate, to a level which is greater by a predetermined increase than the quantity of intake air drawn into the internal combustion engine while the internal combustion engine is idling normally;

means for establishing the predetermined increase depending on the engine temperature of the internal combustion engine;

ignition timing control means for generating a command value for ignition timing of the internal combustion engine according to a feedback control process to converge the rotational speed of the internal combustion engine toward a predetermined target rotational speed, and for controlling the ignition timing of the internal combustion engine based on the generated command value thereby to retard the ignition timing, and

decision means for deciding whether or not the increasing of the quantity of intake air with said intake air quantity control means and the controlling of the ignition timing of the internal combustion engine with said ignition timing control means are to be canceled, based on an elapsed time in which the quantity of intake air increased by said intake air quantity control means, wherein said intake air quantity control means and said ignition timing control means are disabled if the increasing of the quantity of intake air with said intake air quantity control means and the controlling of the ignition timing of the internal combustion engine with said ignition timing control means are to be canceled as decided by said decision means,

wherein said intake air quantity control means comprises means for immediately stopping increasing the quantity of intake air when the increasing of the quantity of intake air is to be canceled as decided by said decision means, and said ignition timing control means comprises means for progressively advancing the ignition timing which has been retarded according to the feedback control process when the controlling of the ignition timing is to be canceled as decided by said decision means.