Method and system for stopping an engine

• US 9,108,613 B2
• Filed: 10/08/2012
• Issued: 08/18/2015
• 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
• Primary Examiner(s): Burgess, Ramya
• Assistant Examiner(s): Hlavka, David J
• Application Number:
  US13/647,215
• Publication Number:
  US 20140100082A1
• Time in Patent Office: 1,044 Days
• Field of Search: 477/5, 477/6, 477/167, 477/166, 477/174, 477/181, 477/164
• US Class Current: 1/1
• 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 a disconnect clutch slip to stop the engine at a desired position; and

adjusting a driveline integrated starter/generator (DISG) torque output in response to an amount of torque transferred across a dual mass flywheel.

2. The method of claim 1, further comprising substantially maintaining speed of a DISG while adjusting the disconnect clutch application force.

3. The method of claim 1, where adjusting the DISG torque output includes decreasing integrated starter/generator torque output when a DISG spring decompresses.

4. The method of claim 1, where adjusting the DISG torque output includes increasing integrated starter/generator torque output when a DISG spring compresses.

5. The method of claim 1, where adjusting the DISG torque output includes cancelling torque disturbances from the dual mass flywheel.

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

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

8. A method for stopping an engine, comprising:

operating a DISG at a first speed;

operating the 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;

adjusting a disconnect clutch application force in response to the engine stop request, where the disconnect clutch application force is increased to close a disconnect clutch from an open position;

stopping the engine and the DISG while the disconnect clutch is closed; and

ceasing spark and fuel flow to the engine and adjusting DISG torque to stop the engine at a desired position, where adjusting DISG torque to stop the engine includes rotating the engine in a reverse direction.

9. The method of claim 8, further comprising opening the disconnect clutch after engine stop.

10. A method for stopping an engine, comprising:

operating a DISG at a first speed;

operating the 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;

adjusting a disconnect clutch application force in response to the engine stop request, further comprising adjusting DISG torque to cancel driveline torque oscillations from a dual mass flywheel.

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

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

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

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

15. The method of claim 13, where adjusting DISG torque to stop the engine includes rotating the engine in a reverse direction.