Method of controlling the stopping and starting of an engine

Patent metadata

Field	Value
Publication number	US-9995229-B2
Application number	US-201615043860-A
Country	US
Kind code	B2
Filing date	Feb 15, 2016
Priority date	Feb 20, 2015
Publication date	Jun 12, 2018
Grant date	Jun 12, 2018

Abstract

A method of stopping and starting an engine of a vehicle having a manually operated clutch system including a clutch for driveably connecting the engine to a transmission includes controlling stopping and starting of the engine based on first and second clutch engagement thresholds selected based on whether the clutch is being engaged or disengaged. The first threshold corresponds to a more disengaged state of the clutch than the second threshold. The first threshold is used when the clutch is being disengaged to decide whether the engine can be shut down while the transmission remains in-gear. The second threshold is used when the clutch is being engaged to decide whether the engine can be started while the transmission remains in-gear. By using a less conservative threshold for starting the engine than stopping the engine, the number of inhibited restarts is reduced.

First claim

What is claimed is:

1. An engine control method for a vehicle, comprising:
stopping the engine, by a controller, in response to disengaging a manual transmission clutch and the clutch being more disengaged than a first clutch disengagement threshold; and
restarting the engine, by the controller, in response to engaging the clutch and the clutch being more disengaged than a second clutch disengagement threshold corresponding to a less disengaged clutch state than the first clutch disengagement threshold.

2. The method of claim 1 further comprising stopping the engine in response to at least one engine stop trigger.

3. The method of claim 2 further comprising inhibiting stopping the engine in response to the clutch being less disengaged than the first clutch disengagement threshold.

4. The method of claim 2 , the at least one engine stop trigger comprising a brake pedal being pressed.

5. The method of claim 1 further comprising restarting the engine in response to at least one engine restart trigger.

6. The method of claim 5 further comprising inhibiting restarting the engine in response to the clutch being less disengaged than the second clutch disengagement threshold.

7. The method of claim 5 wherein the at least one engine restart trigger corresponds to a vehicle brake pedal having been released, or the vehicle brake pedal currently being released.

8. The method of claim 5 , the at least one engine restart trigger including a vehicle brake pedal being sensed to be released and a vehicle accelerator pedal sensed to be pressed.

9. The method of claim 1 , the first clutch disengagement threshold corresponding to a position of the clutch where no torque can be transmitted by the clutch.

10. The method of claim 1 , the second clutch disengagement threshold corresponding to a bite point of the clutch such that any torque that can be transmitted by the clutch is insufficient to move the vehicle.

11. The method of claim 1 , the clutch being actuated by a clutch actuation system including a slave cylinder having a piston arranged to move a release bearing of the clutch and a slave cylinder piston position sensor to provide an output signal indicative of a position of the piston of the slave cylinder, wherein the first clutch disengagement threshold is a first assigned value of output signal from the slave cylinder piston position sensor and, if a magnitude of the output signal from the slave cylinder piston position sensor is not less than the first assigned value of output signal from the slave cylinder piston position sensor, the clutch is considered to be sufficiently disengaged to permit stopping the engine.

12. The method of claim 1 , the clutch being actuated by a clutch actuation system including a slave cylinder having a piston arranged to move a release bearing of the clutch and a slave cylinder piston position sensor to provide an output signal indicative of a position of the piston of the slave cylinder, wherein the second clutch disengagement threshold is a second assigned value of the output signal from the slave cylinder piston position sensor and, if a magnitude of the output signal from the slave cylinder piston position sensor is not less than the second assigned value of output signal from the slave cylinder piston position sensor, the clutch is considered to be sufficiently disengaged to permit restarting of the engine.

13. A vehicle comprising:
a manually operated clutch connecting an engine and a transmission; and
a controller automatically stopping and starting the engine in response to a stop trigger, a start trigger, and a signal indicative of engagement state of the clutch relative to: a first clutch threshold when the clutch is being disengaged and, when the clutch is being engaged, a second clutch threshold representing a less disengaged clutch state than the first clutch threshold.

14. The vehicle of claim 13 further comprising:
a clutch actuation system including a slave cylinder having a piston arranged to move a release bearing of the clutch and a slave cylinder piston position sensor to provide the signal indicative of the engagement state of the clutch based on position of the piston.

15. The vehicle of claim 13 , the first clutch threshold corresponding to a position of the clutch where no torque can be transmitted by the clutch.

16. The vehicle of claim 13 , the second clutch threshold corresponding to a bite point of the clutch such that any torque transmitted by the clutch is insufficient to move the vehicle.

17. A vehicle comprising:
a processor programmed to stop and start an engine based on a position signal for a clutch of a manual transmission with the transmission in-gear, the processor stopping the engine with the transmission in-gear in response to the position signal exceeding a first threshold, and starting the engine with the transmission in-gear in response to the position signal exceeding a second threshold corresponding to less clutch disengagement than the first threshold.

18. The vehicle of claim 17 further comprising a clutch actuation system having a cylinder and piston arranged to move a release bearing of the clutch, the position signal corresponding to position of the piston within the cylinder.

19. The vehicle of claim 17 , the first threshold corresponding to a position of the clutch where no torque is transmitted by the clutch.

20. The vehicle of claim 17 , the second threshold corresponding to a bite point position of the clutch.

Assignees

• Ford Global Tech Llc

Inventors

• Petridis Anthemios Philemon
• Kees Donatus Andreas Josephine
• Christen Urs

Classifications

• F02D41/00

  Electrical control of supply of combustible mixture or its constituents (F02D43/00 takes precedence {; control of engine starters F02N11/08, electrical control of engine ignition timing F02P5/145}) · CPC title

• B60W10/06

  including control of combustion engines · CPC title

• F02D41/045

  Detection of accelerating or decelerating state (detection thereof in general G01P) · CPC title

• B60W2540/14

  Clutch pedal position · CPC title

• F02D41/065

  at hot start or restart (F02D41/067 takes precedence) · CPC title