Method for controlling engine and/or transmission temperature

• US 20060183596A1
• Filed: 02/17/2005
• Published: 08/17/2006
• Est. Priority Date: 02/17/2005
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: General Motors Corporation (General Motors Company)
• Inventors: Johansson, Joseph K.S., Etchason, Edmond M., Kresse, John P.
• Granted Patent: US 7,223,205 B2
• Time in Patent Office: Days
• US Class Current: 477/98
• CPC Class Codes: F01P 11/16 concerning coolant temperature F01P11/20 takes precedence
• CPC Class Codes: F01P 2031/00 Fail safe
• CPC Class Codes: F02D 2250/26 by applying a torque limit
• CPC Class Codes: F02D 41/0215 in relation with elements of the transmission
• CPC Class Codes: F16H 57/0413 Controlled cooling or heating of lubricant; Temperature control therefor
• CPC Class Codes: F16H 59/72 dependent on oil characteristics, e.g. temperature, viscosity

Abstract

The method of the present invention is adapted to control transmission oil temperature. According to a preferred embodiment, the engine coolant temperature may be controlled in addition to or regardless of transmission oil temperature. To maintain transmission and/or engine temperature, the present invention is preferably configured to limit the engine'"'"'s power when required to ensure the powertrain (engine and transmission) does not overheat.

Claims

1. A method for controlling transmission oil temperature, the method comprising:

establishing a predetermined transmission oil reference temperature;

measuring a current transmission oil temperature;

establishing a transmission oil temperature differential by subtracting the current transmission oil temperature from the transmission oil reference temperature;

establishing an engine power limit based on said transmission oil temperature differential; and

limiting an output of an engine to said engine power limit to thereby limit said transmission oil temperature.

2. The method of claim 1, wherein said limiting an output of an engine includes altering the fuel consumption of said engine.

3. The method of claim 1, wherein said limiting an output of an engine includes altering the air intake of said engine.

4. The method of claim 1, wherein said limiting an output of an engine includes adjusting spark timing of said engine.

5. The method of claim 1, wherein said establishing an engine power limit includes calculating an engine output limit proportional to the transmission oil temperature differential.

6. The method of claim 1, wherein said establishing an engine power limit includes integrating the transmission oil temperature differential to calculate an engine output limit.

7. The method of claim 1, further comprising transmitting said engine power limit from a first control module to an engine control module via a serial communications datalink.

8. A method for controlling a powertrain temperature, the powertrain including a transmission and an engine, the transmission having transmission oil, the engine having engine coolant, the method comprising:

establishing a predetermined transmission oil reference temperature;

establishing a predetermined engine coolant reference temperature;

measuring a current transmission oil temperature;

measuring a current engine coolant temperature;

establishing a transmission oil temperature differential by subtracting the current transmission oil temperature from the transmission oil reference temperature;

establishing an engine coolant temperature differential by subtracting the current engine coolant temperature from the engine coolant reference temperature;

establishing a minimum temperature differential by selecting the minimum of said transmission oil temperature differential and said engine coolant temperature differential;

establishing an engine power limit based on said minimum temperature differential; and

limiting engine output to said engine power limit to thereby limit said powertrain temperature.

9. The method of claim 8, wherein said limiting engine output includes altering the fuel consumption of said engine.

10. The method of claim 8, wherein said limiting engine output includes altering the air intake of said engine.

11. The method of claim 8, wherein said limiting engine output includes adjusting spark timing of said engine.

12. The method of claim 8, wherein said establishing an engine power limit includes calculating an engine output limit proportional to the minimum temperature differential.

13. The method of claim 8, wherein said establishing an engine power limit includes integrating the minimum temperature differential to calculate an engine output limit.

14. The method of claim 8, further comprising transmitting said engine power limit from a transmission control module to an engine control module via a serial communications datalink.

15. A method for controlling a powertrain temperature, the powertrain including a transmission and an engine, the transmission having a transmission control module and transmission oil, the engine having an engine control module and engine coolant, the method comprising:

establishing a predetermined transmission oil reference temperature;

establishing a predetermined engine coolant reference temperature;

measuring a current transmission oil temperature;

measuring a current engine coolant temperature;

establishing a transmission oil temperature differential by subtracting the current transmission oil temperature from the transmission oil reference temperature;

establishing an engine coolant temperature differential by subtracting the current engine coolant temperature from the engine coolant reference temperature;

establishing a minimum temperature differential in the transmission control module by selecting the minimum of said transmission oil temperature differential and said engine coolant temperature differential;

establishing an engine power limit based on said minimum temperature differential;

transmitting said engine power limit from the transmission control module to the engine control module; and

limiting engine output to said engine power limit.

16. The method of claim 15, wherein said limiting engine output includes altering the fuel consumption of said engine.

17. The method of claim 15, wherein said limiting engine output includes altering the air intake of said engine.

18. The method of claim 15, wherein said limiting engine output includes adjusting spark timing of said engine.

19. The method of claim 15, wherein said establishing an engine power limit includes calculating an engine output limit proportional to the minimum temperature differential.

20. The method of claim 15, wherein said establishing an engine power limit includes integrating the minimum temperature differential to calculate an engine output limit.