METHODS AND SYSTEMS FOR HEATING TRANSMISSION FLUID

• US 20120198819A1
• Filed: 04/18/2012
• Published: 08/09/2012
• Est. Priority Date: 02/04/2009
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Pursifull, Ross Dykstra
• Granted Patent: US 8,348,807 B2
• Time in Patent Office: Days
• US Class Current: 60/273
• CPC Class Codes: F16H 57/0413 Controlled cooling or heating of lubricant; Temperature control therefor
• CPC Class Codes: F16H 57/0417 Heat exchangers adapted or integrated in the gearing
• CPC Class Codes: F16H 57/0475 Engine and gearing, i.e. joint lubrication or cooling or heating thereof electric machines and gearing F16H57/0476
• CPC Class Codes: F16H 61/0021 Generation or control of line pressure
• CPC Class Codes: F16H 61/0031 using auxiliary pumps, e.g. pump driven by a different power source than the engine

Abstract

Systems and methods are provided for heating transmission fluid in a vehicle, the vehicle comprising an engine and a transmission, the engine including a heat exchanger. One example method comprises, during a first engine running condition, operating an auxiliary transmission fluid pump to generate pressure in the transmission fluid and pump transmission fluid to the heat exchanger, and during a second condition where the engine is not running, operating the auxiliary transmission fluid pump to generate pressure in the transmission fluid and pump transmission fluid to the heat exchanger.

Claims

1-18. -18. (canceled)

19. A method for heating transmission fluid in a vehicle with an engine comprising,

during engine running conditions, operating an auxiliary transmission fluid pump to generate pressure in the transmission fluid and pump transmission fluid to the heat exchanger while flowing exhaust gas to the heat exchanger;

and

during engine not running conditions, operating the auxiliary transmission fluid pump to generate pressure in the transmission fluid and pump transmission fluid to the heat exchanger.

20. The method of claim 19 wherein the auxiliary transmission fluid pump is electrically powered.

21. The method of claim 19 wherein the heat exchanger transfers heat from exhaust gas of an exhaust conduit to the transmission fluid.

22. The method of claim 21 wherein the heat exchanger includes a conduit enclosing the transmission fluid coupled adjacent to the engine exhaust conduit.

23. The method of claim 19 wherein the engine running conditions include a condition where the temperature of the transmission fluid is below a threshold.

24. The method of claim 23 wherein the engine running conditions include an engine cold start operation.

25. The method of claim 24 wherein the engine not running conditions include a condition where the engine is selectively shut-down responsive to engine idle-stop conditions and without receiving an engine shutdown request from an operator.

26. The method of claim 25 further comprising, during other engine running conditions, operating an engine-driven transmission fluid pump to generate pressure in the transmission fluid.

27. The method of claim 26 wherein the other engine running conditions includes a condition where the temperature of the transmission fluid is above the threshold, and wherein operating the engine-driven transmission fluid pump includes not operating the auxiliary transmission fluid pump.

28. A vehicle system, comprising:

an automatic transmission including an engine-driven fluid pump and an auxiliary fluid pump, the pumps configured to pump transmission fluid through the transmission and an oil circuit;

a heat exchanger coupled to an engine exhaust and coupled to the oil circuit; and

a control system configured to,

selectively shut-down the engine responsive to engine idle-stop conditions and without receiving an engine shutdown request from an operator, and restart the engine from the engine shut-down responsive to restart conditions;

operate the auxiliary fluid pump to generate pressure in the transmission fluid and pump transmission fluid to the heat exchanger during a first engine running condition where the temperature of the transmission fluid is below a threshold;

operate the auxiliary fluid pump to generate pressure in the transmission fluid and pump transmission fluid to the heat exchanger during a second condition where the engine is shut-down responsive to the engine idle-stop conditions; and

operate the engine-driven fluid pump to generate pressure in the transmission fluid during a third engine running condition where the temperature of the transmission fluid is above the threshold.

29. The system of claim 28 wherein the auxiliary fluid pump is electrically powered.

30. The system of claim 29 wherein the first engine running condition includes an engine cold start operation.

31. The system of claim 30 wherein operating the engine-driven fluid pump during the third engine running condition includes not operating the auxiliary fluid pump.

32. A method for heating transmission fluid in a vehicle with an engine, comprising,

during engine running conditions, operating an auxiliary transmission fluid pump to generate pressure in the transmission fluid and pump transmission fluid to the heat exchanger via a transmission fluid circuit while flowing exhaust gas to the heat exchanger;

and

during engine not running conditions, operating the auxiliary transmission fluid pump to generate pressure in the transmission fluid and pump transmission fluid to the heat exchanger, wherein a diverter valve selectively operates the transmission fluid circuit as a transmission heating and transmission cooling circuit.

33. The method of claim 32 wherein the auxiliary transmission fluid pump is electrically powered.

34. The method of claim 33 wherein the engine running conditions include a condition where the temperature of the transmission fluid is below a threshold.

35. The method of claim 34 wherein the engine running conditions include an engine cold start operation.