Methods and systems for improving transmission shifting

• US 10,525,967 B2
• Filed: 11/22/2017
• Issued: 01/07/2020
• 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: Pietron, Gregory Michael, Doering, Jeffrey Allen, Reed, Dennis Craig, Gibson, Alex O'Connor, Lee, Seung-Hoon
• Primary Examiner(s): Young, Edwin A
• Application Number:
  US15/820,651
• Publication Number:
  US 20180093657A1
• Time in Patent Office: 776 Days
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/023 Fluid clutches
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 10/30 including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps
• CPC Class Codes: B60W 20/14 in conjunction with braking regeneration
• 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 2030/203 related or induced by the clutch
• CPC Class Codes: B60W 2510/0275 Clutch torque
• CPC Class Codes: B60W 2510/083 Torque
• CPC Class Codes: B60W 30/20 Reducing vibrations in the driveline
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/902 Prime movers comprising electrical and internal combustion motors
• 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, an engine is couple to a transmission in response to a transmission upshift to reduce transmission output shaft torque disturbances.

Claims

1. A method comprising:

operating a hybrid-electric vehicle with a mechanical transmission with a plurality of clutches responsive to an operator input, the mechanical transmission separate from an engine via a driveline disconnect clutch;

in response to each of an automatic request to restart the engine and to shift the transmission, and after release of an off-going clutch, initiating application of an on-coming clutch and applying a load from the engine to an input shaft of the transmission via initiating application of the driveline disconnect clutch, the application of the on-coming clutch and the application of the driveline disconnect clutch initiated concurrently.

2. The method of claim 1, wherein the engine is coupled through the driveline disconnect clutch to a driveline integrated starter/generator.

3. The method of claim 1, wherein the transmission is a dual layshaft dual clutch transmission.

4. The method of claim 1, where the engine does not apply the load to the input shaft of the transmission prior to the request to restart the engine and shift the transmission, where the transmission is in a moving vehicle and in a forward drive gear, where the vehicle continues to move, and where the transmission is shifted to a higher gear.

5. The method of claim 1, where an application rate of the driveline disconnect clutch is adjusted responsive to a desired cranking torque for the engine, and where the driveline disconnect clutch is positioned in a driveline between the engine and a torque converter.

6. The method of claim 1, where the engine is accelerated from rest to a desired cranking speed via the application of the driveline disconnect clutch.

7. The method of claim 1, further comprising starting the engine when engine speed reaches a threshold speed, and where input torque to the transmission is reduced during the shift of the transmission.

8. The method of claim 1, wherein applying the load from the engine to the input shaft of the transmission comprises rotating the engine with torque applied from a driveline integrated starter/generator (DISG) to the input shaft of the transmission.

9. A method for shifting a transmission of a hybrid-electric vehicle, comprising:

in response to a transmission upshift request and a request to restart an engine, determining an availability of a driveline integrated starter/generator (DISG) based on a state of charge of a battery, the battery at least partly charged by a solar charging system of the vehicle, wherein an estimate of an amount of charge provided to the battery by the solar charging system during vehicle driving is generated; and

responsive to determining that the DISG is available, releasing an off-going clutch, initiating application of an on-coming clutch, reducing input torque to the transmission and accelerating the engine to a desired cranking speed by coupling the engine to an input shaft of the transmission with a driveline disconnect clutch; and

rotating the engine with torque applied from the DISG to the input shaft of the transmission, the engine not coupled to the input shaft of the transmission prior to the transmission upshift request; and

responsive to determining that the DISG is unavailable, releasing the off-going clutch, applying the on-coming clutch, and applying the driveline disconnect clutch, an application pressure of the driveline disconnect clutch increased until an impeller speed of a torque converter is reduced to less than a threshold speed.

10. The method of claim 9, where a driveline disconnect clutch application rate is based on a speed of the DISG and the desired cranking speed.

11. The method of claim 9, where the torque converter is positioned in a driveline positioned between the engine and the transmission.

12. The method of claim 9, further comprising, when the DISG is available, increasing or decreasing torque of the DISG during the transmission upshift request.

13. The method of claim 12, where torque from the DISG is increased to hold the impeller speed of the torque converter greater than the threshold speed.

14. The method of claim 9, where engine rotation is stopped prior to the transmission upshift request, and where coupling the engine to the input shaft of the transmission with the driveline disconnect clutch accelerates the engine from rest.

15. The method of claim 9, wherein the application pressure of the driveline disconnect clutch is not further increased after the torque converter impeller speed is reduced to less than the threshold speed.

16. A hybrid vehicle system, comprising:

an engine;

a solar charging system of a vehicle;

a driveline disconnect clutch mechanically including a first side coupled to a second side of a dual mass flywheel;

a driveline integrated starter/generator (DISG) including a first side coupled to a second side of the driveline disconnect clutch;

a battery configured to receive charge from the DISG and the solar charging system;

a transmission coupled to the DISG; and

a controller including non-transitory instructions executable to;

initiate each of an engine start and a transmission shift request responsive to a battery state of charge;

release an off-going clutch; and

after a predetermined time period, begin applying an on-coming clutch and begin applying the driveline disconnect clutch concurrently to couple the engine to an input shaft of the transmission, wherein the driveline disconnect clutch application is modulated in response to an engine speed.

17. The hybrid vehicle system of claim 16, further comprising a torque converter located in a driveline between the transmission and the DISG.

18. The hybrid vehicle system of claim 16, where the driveline disconnect clutch application is further modulated in response to a transmission output shaft speed.

19. The hybrid vehicle system of claim 16, further comprising additional instructions to increase DISG torque in response to the transmission shift request.

20. The hybrid vehicle system of claim 16, further comprising additional instructions to reduce DISG torque in response to the transmission shift request.

21. The hybrid vehicle system of claim 16, further comprising additional instructions to accelerate the engine to a desired cranking speed.

22. The hybrid vehicle system of claim 16, further comprising additional instructions to rotate the engine with torque applied from the DISG to the input shaft of the transmission after coupling the engine to the input shaft of the transmission.