Adaptable thermal management of a vehicle dual-clutch transmission

• US 8,849,532 B2
• Filed: 04/20/2012
• Issued: 09/30/2014
• Est. Priority Date: 04/20/2012
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Burtch, Joseph B.
• Primary Examiner(s): Jabr, Fadey
• Assistant Examiner(s): INGRAM, THOMAS P
• Application Number:
  US13/452,137
• Publication Number:
  US 20130282247A1
• Time in Patent Office: 893 Days
• Field of Search: 701/33.4, 701/60, 701/67, 477/70, 477/76, 477/97, 477/98, 477/174, 477/175, 477/176
• US Class Current: 701/67
• CPC Class Codes: F16D 2500/10412 Transmission line of a vehicle
• CPC Class Codes: F16D 2500/1086 Concentric shafts
• CPC Class Codes: F16D 2500/30404 Clutch temperature
• CPC Class Codes: F16D 2500/30405 Estimated clutch temperature
• CPC Class Codes: F16D 2500/30406 Clutch slip
• CPC Class Codes: F16D 2500/3166 Detection of an elapsed period of time
• CPC Class Codes: F16D 2500/50296 Limit clutch wear
• CPC Class Codes: F16D 48/062 of a clutch system with a plurality of fluid actuated clutches
• CPC Class Codes: F16D 48/066 Control of fluid pressure, e.g. using an accumulator F16D48/062, F16D48/068 take precedence
• CPC Class Codes: F16H 2057/014 of friction elements in transmissions
• CPC Class Codes: F16H 2059/465 Detecting slip, e.g. clutch slip ratio
• CPC Class Codes: F16H 2059/6807 Status of gear-change operation, e.g. clutch fully engaged
• CPC Class Codes: F16H 2059/725 Sensing or calculating temperature of friction devices, e.g. clutches to prevent overheating of friction linings
• CPC Class Codes: F16H 59/48 Inputs being a function of acceleration

Abstract

A method of managing clutch thermal loads in a multi-speed dual-clutch transmission (DCT) that is paired with an engine in a vehicle. The method includes assessing whether the vehicle is being accelerated and identifying a DCT clutch slipping during the acceleration. The method also includes determining vehicle parameters, determining an amount of time remaining for the clutch to stop slipping using the determined vehicle parameters, and determining an amount of time remaining until the clutch reaches a threshold temperature. The method additionally includes comparing the determined amount of time remaining for the clutch to stop slipping with the determined amount of time remaining until the clutch reaches the threshold temperature. Furthermore, the method includes activating an indicator if the determined amount of time remaining until the clutch reaches the threshold temperature is less than the determined amount of time remaining for the clutch to stop slipping.

Claims

1. A method of managing clutch thermal loads in a multi-speed dual-clutch transmission (DCT) that is paired with an internal combustion engine in a vehicle, the method comprising:

assessing via a controller whether the vehicle is being accelerated by the engine;

identifying via the controller a clutch in the DCT that is being slipped during the acceleration;

determining via the controller vehicle parameters indicative of a preset amount of time remaining until the clutch will cease to slip;

accessing via the controller the preset amount of time remaining until the clutch will cease to slip that corresponds to the determined vehicle parameters;

determining via the controller an actual amount of time remaining until the clutch being slipped reaches a threshold temperature;

comparing via the controller the accessed preset amount of time remaining until the clutch will cease to slip with the determined actual amount of time remaining until the clutch being slipped reaches the threshold temperature to determine whether the clutch is predicted to cease slipping before the threshold temperature has been reached; and

activating via the controller an indicator if the determined actual amount of time remaining until the clutch being slipped reaches the threshold temperature is less than the accessed preset of time remaining until the clutch will cease to slip.

2. The method of claim 1, wherein the threshold temperature is indicative of the clutch being overheated, the method further comprising regulating an operation of the DCT such that energy input to the clutch is reduced when the clutch substantially reaches the threshold temperature.

3. The method of claim 2, wherein said regulating the operation of the DCT such that energy input to the clutch is reduced includes disengaging the clutch.

4. The method of claim 1, wherein the clutch is in the process of being engaged in a forward gear ratio of the DCT and the clutch ceases to slip upon an upshift to another forward gear ratio using another clutch.

5. The method of claim 4, wherein the determined vehicle parameters include road speed and acceleration of the vehicle, and position of a vehicle accelerator.

6. The method of claim 1, wherein the clutch is in the process of being engaged in a reverse gear ratio of the DCT and the clutch ceases to slip upon lock up of the clutch.

7. The method of claim 1, further comprising activating the indicator when the clutch substantially reaches the threshold temperature.

8. The method of claim 1, wherein the indicator is at least one of an audible signal and a visual display.

9. The method of claim 8, wherein the indicator is the visual display, and wherein the visual display includes a request for an operator of the vehicle to at least one of i) increase speed or apply a vehicle brake, and ii) apply and hold the vehicle brake.

10. The method of claim 1, wherein the clutch is one of an odd-ratio clutch and an even-ratio clutch.

11. A vehicle comprising:

an internal combustion engine configured to generate engine torque;

a drive wheel configured to interface with a road surface;

a multi-speed dual-clutch transmission (DCT) operatively connected to the engine and configured to transmit engine torque to the drive wheel; and

a controller configured to;

assess whether the vehicle is being accelerated by the engine;

identify a clutch in the DCT that is being slipped during the acceleration;

determine vehicle parameters indicative of a preset amount of time remaining until the clutch will cease to slip;

access the preset amount of time remaining until the clutch will cease to slip that corresponds to the determined vehicle parameters;

determine an actual amount of time remaining until the clutch being slipped reaches a threshold temperature;

compare the accessed amount of time remaining until the clutch will cease to slip with the determined actual amount of time remaining until the clutch being slipped reaches the threshold temperature to determine whether the clutch is predicted to cease slipping before the threshold temperature has been reached; and

activate an indicator if the determined actual amount of time remaining until the clutch being slipped reaches the threshold temperature is less than the accessed amount of time remaining until the clutch will cease to slip.

12. The vehicle of claim 11, wherein the threshold temperature is indicative of the clutch being overheated, and wherein the controller is additionally configured to regulate the operation of the DCT such that energy input to the clutch is reduced when the clutch substantially reaches the threshold temperature.

13. The vehicle of claim 12, wherein the controller regulates operation of the DCT such that energy input to the clutch is reduced by disengaging the clutch.

14. The vehicle of claim 11, wherein the clutch is in the process of being engaged in a forward gear ratio of the DCT and the clutch ceases to slip upon an upshift to another forward gear ratio using another clutch.

15. The vehicle of claim 14, wherein the determined vehicle parameters include road speed and acceleration of the vehicle, and position of a vehicle accelerator.

16. The vehicle of claim 11, wherein the clutch is in the process of being engaged in a reverse gear ratio of the DCT and the clutch ceases to slip upon lock up of the clutch.

17. The vehicle of claim 11, wherein the controller is additionally configured to activate the indicator when the clutch substantially reaches the threshold temperature.

18. The vehicle of claim 11, wherein the indicator is at least one of an audible signal and a visual display.

19. The vehicle of claim 18, wherein the indicator is the visual display, and wherein the visual display includes a request for an operator of the vehicle to at least one of i) increase speed or apply a vehicle brake, and ii) apply and hold the vehicle brake.