Method and Apparatus for Improving Vehicle Fuel Economy

• US 20070295475A1
• Filed: 06/27/2006
• Published: 12/27/2007
• Est. Priority Date: 06/27/2006
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (General Motors Company)
• Inventors: Samie, Farzad, Carlson, Richard W.
• Granted Patent: US 8,042,609 B2
• Time in Patent Office: Days
• US Class Current: 165/41
• CPC Class Codes: F16H 57/0412 Cooling or heating; Control of temperature
• CPC Class Codes: F16H 57/0413 Controlled cooling or heating of lubricant; Temperature control therefor
• CPC Class Codes: F16H 57/0415 Air cooling or ventilation; Heat exchangers; Thermal insulations

Abstract

The present invention provides an apparatus for improving the fuel economy of a vehicle. The apparatus includes a transmission having a transmission sump that contains transmission fluid, and a heat exchanger disposed within said sump and at least partially submerged in the transmission fluid. The apparatus also includes an engine having a plurality of engine coolant channels. An engine pump is operatively connected to the engine. The engine pump is configured to transfer engine coolant through the plurality of engine coolant channels and then through the heat exchanger. Heat from the engine coolant is transferred to the transmission fluid when the engine coolant passes through the heat exchanger. The heat transferred to the transmission fluid decreases transmission fluid viscosity such that transmission spin losses are reduced and fuel economy is improved. A corresponding method for improving the fuel economy of a vehicle is also provided.

Claims

1. An apparatus for improving the fuel economy of a vehicle comprising:

a transmission including;

a sump containing a transmission fluid; and

a heat exchanger disposed in heat exchange relationship with the transmission fluid within the sump;

an engine operatively connected to the transmission, said engine having an engine coolant channel; and

an engine pump operatively connected to said engine, said engine pump configured to transfer engine coolant through said coolant channel and then through the heat exchanger;

wherein engine heat is absorbed by the engine coolant as the engine coolant passes through the engine coolant channel, and heat from the engine coolant is absorbed by the transmission fluid as the engine coolant passes through the heat exchanger such that transmission fluid viscosity is decreased thereby reducing transmission spin losses and improving vehicle fuel economy.

2. The apparatus of claim 1, further comprising a first valve configured to selectively prevent the flow of the engine coolant from the engine coolant channel to the heat exchanger.

3. The apparatus of claim 2, further comprising a radiator operatively connected to the engine and configured to reduce the temperature of the engine coolant.

4. The apparatus of claim 3, further comprising a second valve configured to selectively prevent the flow of the engine coolant from the coolant channel to the radiator.

5. The apparatus of claim 4, further comprising a transmission fluid cooler operatively connected to the transmission.

6. The apparatus of claim 5, further comprising a transmission pump configured to transfer transmission fluid from the sump to the transmission fluid cooler.

7. The apparatus of claim 6, further comprising a third valve configured to selectively prevent the flow of the transmission fluid from the sump to the transmission fluid cooler.

8. The apparatus of claim 7, further comprising a heater core adapted to receive the engine coolant from the engine coolant channel and thereafter transfer the engine coolant back to the engine pump.

9. The apparatus of claim 1, wherein the heat exchanger is at least partially submerged in the transmission fluid.

10. A method of reducing spin losses in a vehicle powertrain including an internal combustion engine and a transmission having transmission oil, and comprising:

selectively exchanging heat between said engine and said transmission oil sufficiently during warm-up of said engine to reduce the viscosity of said transmission oil, and the time required to reach operating temperature of said transmission.

11. A method of improving performance of a vehicle powertrain including an internal combustion engine having engine coolant and a transmission having transmission oil, and comprising:

selectively exchanging heat between said engine coolant and said transmission oil during periods of heavy vehicle load in order to cool said transmission oil.

12. A method for improving the fuel economy of a vehicle comprising:

providing engine coolant to absorb heat from an engine;

providing a heat exchanger in fluid communication with the engine coolant, said heat exchanger being at least partially submerged in a transmission fluid within a transmission sump; and

transferring the engine coolant through the heat exchanger such that heat from the engine coolant is absorbed by the transmission fluid, wherein the transmission fluid'"'"'s viscosity is decreased thereby reducing spin losses and improving fuel economy.

13. The method of claim 12, further comprising selectively blocking the transfer of the engine coolant to the heat exchanger.

14. The method of claim 13, wherein said transferring the engine coolant includes implementing an engine pump to transfer the engine coolant.