METHODS AND SYSTEMS FOR A FOUR WHEEL DRIVE VEHICLE DRIVELINE

• US 20130296101A1
• Filed: 10/15/2012
• Published: 11/07/2013
• Est. Priority Date: 05/04/2012
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Doering, Jeffrey Allen, Gibson, Alex O'Connor, Pietron, Gregory Michael, McCallum, James William Loch, Fujii, Yuji
• Granted Patent: US 9,278,692 B2
• Time in Patent Office: Days
• US Class Current: 477/4
• CPC Class Codes: B60K 17/28 characterised by arrangement, location, or type of power take-off
• 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: B60K 6/52 Driving a plurality of drive axles, e.g. four-wheel drive
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/023 Fluid clutches
• CPC Class Codes: B60W 10/026 of lock-up 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 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 10/30 including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps
• CPC Class Codes: B60W 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 20/13 in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion
• 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 2510/1005 Transmission ratio engaged
• CPC Class Codes: B60W 2520/403 between front and rear axle
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 2540/16 Ratio selector position
• CPC Class Codes: B60W 2710/021 Clutch engagement state
• CPC Class Codes: B60W 2710/024 of torque converter lock-up clutch
• CPC Class Codes: B60W 2710/027 : Clutch torque
• CPC Class Codes: B60W 2710/065 : Idle condition
• CPC Class Codes: B60W 2710/083 : Torque
• CPC Class Codes: B60W 30/02 : Control of vehicle driving stability
• CPC Class Codes: B60W 30/18 : Propelling the vehicle
• CPC Class Codes: B60W 30/18018 : Start-stop drive, e.g. in a traffic jam
• CPC Class Codes: B60W 30/18045 : Rocking, i.e. fast change between forward and reverse
• CPC Class Codes: B60W 30/18063 : Creeping
• CPC Class Codes: B60Y 2200/92 : Hybrid vehicles
• CPC Class Codes: B60Y 2300/188 : Controlling power parameters of the driveline, e.g. determining the required power
• CPC Class Codes: B60Y 2300/42 : Control of clutches
• CPC Class Codes: B60Y 2300/421 : Control of lock-up type clutches, e.g. in a torque converter
• CPC Class Codes: B60Y 2300/43 : Control of engines
• CPC Class Codes: B60Y 2300/60 : Control of electric machines, e.g. problems related to electric motors or generators
• CPC Class Codes: F01P 3/00 : Liquid cooling
• CPC Class Codes: F02D 41/065 : at hot start or restart F02D41/067 takes precedence
• CPC Class Codes: F02N 11/003 : said electric motor being also used as a drive for auxiliaries, e.g. for driving transmission pumps or fuel pumps during engine stop
• CPC Class Codes: F02N 11/04 : the motors being associated with current generators
• CPC Class Codes: F02N 11/0833 : Vehicle conditions F02N11/0822, F02N11/0825 take precedence
• CPC Class Codes: F02N 11/084 : State of vehicle accessories, e.g. air condition or power steering
• CPC Class Codes: F02N 2200/124 : Information about road conditions, e.g. road inclination or surface
• CPC Class Codes: Y02T 10/40 : Engine management systems
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y10S 477/90 : Control signal is vehicle weight
• CPC Class Codes: Y10S 903/916 : with plurality of drive axles
• CPC Class Codes: Y10S 903/93 : Conjoint control of different elements

Abstract

Systems and methods for improving operation of a hybrid vehicle are presented. In one example, driveline operation may be adjusted in response to operating the hybrid vehicle in a four wheel drivel low gear range. The approaches may improve vehicle drivability and reduce driveline degradation.

Claims

1. A method of adjusting operation of a hybrid vehicle, comprising:

automatically restarting an engine in response to a first condition while the hybrid vehicle is operating in a four wheel drive low gear range; and

automatically restarting the engine in response to a second condition other than the first condition while the hybrid vehicle is not operating in the four wheel drive low gear range.

2. The method of claim 1, where the engine is not started in response to releasing a brake pedal during the second condition, and where the engine is started in response to releasing a brake pedal during the first condition.

3. The method of claim 1, where the hybrid vehicle is operating in a four wheel drive high gear range during the second condition.

4. The method of claim 1, where the hybrid vehicle is operating in a two wheel drive mode during the second condition.

5. The method of claim 1, further comprising providing wheel torque up to a threshold amount via a driveline integrated starter generator without supplying torque via the engine after restarting the engine during the second condition.

6. The method of claim 5, further comprising providing wheel torque via the driveline integrated starter generator and the engine for wheel torques greater than the threshold amount.

7. The method of claim 1, where the hybrid vehicle includes a driveline disconnect clutch, and further comprising locking the driveline disconnect clutch in a closed state while the hybrid vehicle is operated in a four wheel drive mode and until the four wheel drive mode is exited.

8. A method of adjusting operation of a hybrid vehicle, comprising:

automatically restarting an engine in response to release of a vehicle brake while the hybrid vehicle is operating in a four wheel drive low gear range; and

commanding a torque to a torque converter impeller while the hybrid vehicle is operated in the four wheel drive low gear range that is different than a torque supplied to the torque converter impeller during similar operating condition while the hybrid vehicle is operated in a two wheel drive mode.

9. The method of claim 8, further comprising operating the engine for a longer engine idle time after automatic engine stop conditions other than idle time have been met while the hybrid vehicle is operated in the four wheel drive low gear range as compared to engine idle time after automatic engine stop conditions other than idle time have been met while the hybrid vehicle is operated in a two wheel drive mode.

10. The method of claim 8, further comprising operating the engine for a longer engine idle time after automatic engine stop conditions other than idle time have been met while the hybrid vehicle is operated in the four wheel drive low gear range as compared to engine idle time after automatic engine stop conditions other than idle time have been met while the hybrid vehicle is operated in a four wheel drive high gear range.

11. The method of claim 8, further comprising automatically restarting the engine in response to a threshold desired wheel torque amount while the hybrid vehicle is not operating in the four wheel drive low gear range.

12. The method of claim 8, further comprising adjusting opening and closing conditions for a driveline disconnect clutch in response to operating the hybrid vehicle in the four wheel drive low gear range.

13. The method of claim 12, where adjusting opening and closing conditions for the driveline disconnect clutch includes opening and closing the driveline disconnect clutch according to a different driveline disconnect clutch application schedule than when the hybrid vehicle is operated in a four wheel drive high gear range.

14. The method of claim 12, where adjusting opening and closing conditions for the driveline disconnect clutch includes opening and closing the driveline disconnect clutch according to a different driveline disconnect clutch application schedule than when the hybrid vehicle is operated in a two wheel drive mode.

15. A method of adjusting operation of a hybrid vehicle, comprising:

automatically restarting an engine in response to release of a vehicle brake while the hybrid vehicle is operating in a four wheel drive low gear range; and

stopping engine rotation in response to a vehicle battery reaching a first threshold state of charge based on operating the hybrid vehicle in the four wheel drive low gear range.

16. The method of claim 15, further comprising stopping engine rotation in response to the vehicle battery reaching a second threshold state of charge based on operating the hybrid vehicle in a mode other than the four wheel drive low gear range.

17. The method of claim 16, where the mode other than the four wheel drive low gear range is a two wheel drive mode.

18. The method of claim 16, where the mode other than the four wheel drive low gear range is a four wheel drive high gear range.

19. The method of claim 15, further comprising opening and closing a driveline disconnect clutch according to a first schedule based on operating the hybrid vehicle in the four wheel drive low gear range.

20. The method of claim 19, further comprising opening and closing the driveline disconnect clutch according to a second schedule based on operating in the hybrid vehicle in a two wheel drive mode, the second schedule different from the first schedule.

21. A method of adjusting operation of a hybrid vehicle, comprising:

automatically restarting a stopped engine in response to a driver selecting a four wheel drive range.

22. The method of claim 21, where the driver selects four wheel drive range while in a two wheel drive range.

23. The method of claim 21, where the four wheel drive range is a high or low gear range.