Engine control apparatus and engine control method

• US 6,494,809 B1
• Filed: 10/23/2000
• Issued: 12/17/2002
• Est. Priority Date: 11/19/1999
• Status: Expired due to Term

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Suzuki, Takashi, Suzuki, Naoto, Takaoka, Toshifumi, Okada, Daimon
• Primary Examiner(s): Bonck, Rodney H.
• Assistant Examiner(s): Le, David D.
• Application Number:
  US09/694,009
• Time in Patent Office: 785 Days
• Field of Search: 477/107, 477/3, 477/111, 477/110, 701/112, 701/113
• US Class Current: 477/107
• CPC Class Codes: B60K 2006/268 Electric drive motor starts the engine, i.e. used as starter motor
• CPC Class Codes: B60K 6/485 Motor-assist type
• CPC Class Codes: B60K 6/543 the transmission being a continuously variable transmission
• CPC Class Codes: B60L 2240/486 Operating parameters
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2540/16 Ratio selector position
• CPC Class Codes: B60W 2710/105 Output torque
• CPC Class Codes: B60W 2710/1061 Output power
• CPC Class Codes: B60W 30/18036 Reversing
• CPC Class Codes: F02N 11/08 Circuits or control means specially adapted for starting of engines
• CPC Class Codes: F02N 11/0833 Vehicle conditions F02N11/0822, F02N11/0825 take precedence
• CPC Class Codes: F02N 2200/0802 Transmission state, e.g. gear ratio or neutral state
• CPC Class Codes: F02N 2300/2002 using different starting modes, methods, or actuators depending on circumstances, e.g. engine temperature or component wear
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/903 having energy storing means, e.g. battery, capacitor
• CPC Class Codes: Y10S 903/918 Continuously variable

Abstract

In a vehicular engine control apparatus, the engine is stopped upon fulfillment of a predetermined stopping condition even in the case where the shift position of the vehicle is a running position, and the engine is restarted afterwards upon fulfillment of a predetermined starting condition. The predetermined starting condition is switched depending on whether the detected shift position is a running position or a non-running position. This reduces a sense of incongruity or unpleasantness caused to the driver in stopping and starting an engine during operation of a vehicle and thereby improves driveability of the vehicle.

Claims

1. An engine control apparatus comprising:

a shift position detector that detects a shift position of a vehicle in which the engine is installed; and

a controller that stops the engine upon fulfillment of a stopping condition and that restarts the engine afterwards

     1) upon fulfillment of a first starting condition when the detected shift position is a running position and

     2) upon fulfillment of a second starting condition when the detected shift position is a non-running position, wherein the first starting condition is established based on whether a power requirement exceeds a first starting determination threshold and the second starting condition is established based on whether the power requirement exceeds a second starting determination threshold, the first starting determination threshold is different from the second starting determination threshold so that the first starting condition makes it less likely to restart the engine than the second starting condition.

2. The apparatus according to claim 1, wherein:

when the engine is started on the basis of the first starting condition, the controller sets a torque change rate of driven wheels of the vehicle to a value no greater than a predetermined value.

3. The apparatus according to claim 1, further comprising:

a vehicle speed detector that detects a speed of the vehicle, wherein;

the controller restarts the engine on the basis of the first starting condition when the detected shift position is a running position and the detected vehicle speed is equal to or smaller than a predetermined value.

4. The apparatus according to claim 3, wherein:

when the engine is started on the basis of the first starting condition, the controller sets a torque change rate of driven wheels of the vehicle to a predetermined value or less.

5. The apparatus according to claim 1, wherein:

the controller prohibits the engine from being stopped even upon fulfillment of the stopping condition, when the detected shift position is a backward position.

6. The apparatus according to claim 5, wherein the controller counts an elapsed time after the switching of the shift position to the backward position, and wherein the controller prohibits the engine from being stopped if the elapsed time is equal to or greater than a predetermined value.

7. The apparatus according to claim 1, wherein:

the non-running position includes a neutral position and a parking position.

8. A control system for a hybrid vehicle comprising:

the engine control apparatus according to claim 1.

9. An engine control method comprising:

detecting a shift position of a vehicle in which the engine is installed;

stopping the engine upon fulfillment of a stopping condition; and

restarting the engine

     1) upon fulfillment of a first starting condition after the stopping of the engine when the detected shift position is a running position and

     2) upon fulfillment of a second starting condition after the stopping of the engine when the detected shift position is a non-running position, wherein the first starting condition is established based on whether a power requirement exceeds a first starting determination threshold and the second starting condition is established based on whether the power requirement exceeds a second starting determination threshold, the first starting determination threshold is different from the second starting determination threshold so that the first starting condition makes it less likely to restart the engine than the second starting condition.

10. The method according to claim 9, further comprising

setting a torque change rate of driven wheels of the vehicle to a value no greater than a predetermined value when the engine is started on the basis of the first starting condition.

11. The method according to claim 9, further comprising:

detecting a speed of the vehicle; and

restarting the engine on the basis of the first starting condition when the detected shift position is a running position and the detected vehicle speed is equal to or smaller than a predetermined value.

12. The method according to claim 11, further comprising:

setting a torque change rate of driven wheels of the vehicle to a predetermined value or less when the engine is started on the basis of the first starting condition.

13. The method according to claim 9, further comprising:

prohibiting the engine from being stopped even upon fulfillment of the stopping condition when the detected shift position is a backward position.

14. The method according to claim 13, further comprising:

counting an elapsed time after the switching of the shift position to the backward position; and

prohibiting the engine from being stopped when the elapsed time is equal to or greater than a predetermined value.

15. The method according to claim 9, wherein:

the non-running position includes a neutral position and a parking position.