METHOD AND SYSTEM FOR STOPPING AN ENGINE

• US 20140100082A1
• Filed: 10/08/2012
• Published: 04/10/2014
• Est. Priority Date: 10/08/2012
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Gibson, Alex O'Connor, Oshinsky, David, Lee, Seung-Hoon, Doering, Jeffrey Allen, Reed, Dennis Craig
• Granted Patent: US 9,108,613 B2
• Time in Patent Office: Days
• US Class Current: 477/167
• CPC Class Codes: B60K 2006/4825 Electric machine connected or connectable to gearbox input shaft
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 20/40 Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers power-up or power-down of the driveline B60W30/192
• CPC Class Codes: B60W 2510/02 Clutches
• CPC Class Codes: B60W 2510/06 Combustion engines, Gas turbines
• CPC Class Codes: B60W 2510/0685 Engine crank angle
• CPC Class Codes: B60W 2710/06 Combustion engines, Gas turbines
• CPC Class Codes: B60W 2710/0644 Engine speed
• CPC Class Codes: B60W 30/20 Reducing vibrations in the driveline
• CPC Class Codes: B60Y 2300/48 Engine direct start by injecting fuel and fire
• CPC Class Codes: B60Y 2400/48 Vibration dampers, e.g. dual mass flywheels
• CPC Class Codes: F02N 19/005 Aiding engine start by starting from a predetermined position, e.g. pre-positioning or reverse rotation
• CPC Class Codes: F02N 2019/008 the engine being stopped in a particular position
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

A method and a system for improving operation of a hybrid vehicle are presented. In one example, a disconnect clutch is operated in response to an engine stop request to adjust an engine stopping position during an engine shutdown. The approach may reduce engine starting time after the engine stop.

Claims

1. A method for stopping an engine, comprising:

adjusting a disconnect clutch application force in response to an engine stop request, and further adjusting the disconnect clutch slip to stop the engine at a desired position.

2. The method of claim 1, further comprising substantially maintaining speed of a driveline integrated starter/generator while adjusting the disconnect clutch application force.

3. The method of claim 1, further comprising adjusting a driveline integrated starter/generator torque output in response to an amount of torque transferred across a dual mass flywheel.

4. The method of claim 3, where adjusting the driveline integrated starter/generator torque output includes decreasing integrated starter/generator torque output when a driveline integrated starter/generator spring decompresses.

5. The method of claim 3, where adjusting the driveline integrated starter/generator torque output includes increasing integrated starter/generator torque output when a driveline integrated starter/generator spring compresses.

6. The method of claim 3, where adjusting the driveline integrated starter/generator torque output includes cancelling torque disturbances from the dual mass flywheel.

7. The method of claim 1, further comprising ceasing spark and fuel delivery to the engine in response to the engine stop request.

8. The method of claim 1, where the disconnect clutch slip is adjusted according to a predetermined schedule.

9. A method for stopping an engine, comprising:

operating a DISG at a first speed;

operating an engine at a second speed different than the first speed;

adjusting the DISG and engine to a same speed in response to an engine stop request; and

adjusting a disconnect clutch application force in response to the engine stop request.

10. The method of claim 9, where the disconnect clutch application force is increased to close a disconnect clutch from an open position.

11. The method of claim 10, further comprising stopping the engine and the DISG while the disconnect clutch is closed.

12. The method of claim 11, further comprising ceasing spark and fuel flow to the engine and adjusting DISG torque to stop the engine at a desired position.

13. The method of claim 12, further comprising opening the disconnect clutch after engine stop.

14. The method of claim 12, where adjusting DISG torque to stop the engine includes rotating the engine in a reverse direction.

15. The method of claim 9, further comprising adjusting DISG torque to cancel driveline torque oscillations from a dual mass flywheel.

16. A system for stopping an engine, comprising:

an engine;

a DISG;

a disconnect clutch positioned in a driveline between the engine and the DISG;

a dual mass flywheel positioned in the driveline between the engine and the disconnect clutch; and

a controller, the controller including non-transitory executable instructions for adjusting an engine stopping position via adjusting a disconnect clutch application force.

17. The system of claim 16, where the non-transitory executable instructions for adjusting the disconnect clutch application force include slipping the disconnect clutch after at least one of spark and fuel flow to the engine cease.

18. The system of claim 16, where the non-transitory executable instructions for adjusting the disconnect clutch application force include closing the disconnect clutch before at least one of spark and fuel flow to the engine cease.

19. The system of claim 16, further comprising additional non-transitory executable instructions for cancelling driveline torque disturbances of the dual mass flywheel.

20. The system of claim 16, further comprising additional non-transitory executable instructions for reversing a direction of the engine after an engine stop and before an engine start.