System and method of changing engine performance curves to manage heat generation

• US 20100152983A1
• Filed: 12/17/2008
• Published: 06/17/2010
• Est. Priority Date: 12/17/2008
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Crowell, Thomas J.
• Granted Patent: US 8,214,115 B2
• Time in Patent Office: Days
• US Class Current: 701/54
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 2510/1005 Transmission ratio engaged
• CPC Class Codes: E02F 9/2066 of the type combustion engines
• CPC Class Codes: E02F 9/2246 Control of prime movers, e.g. depending on the hydraulic load of work tools
• CPC Class Codes: F02D 41/0225 in relation with the gear ratio or shift lever position
• CPC Class Codes: F02D 41/40 with means for controlling injection timing or duration

Abstract

A system and method for managing the heat produced by operation of an internal combustion system utilizes an electronic controller to control operation the engine that is coupled to a transmission. The transmission can include a high drive ratio and a low drive ratio. Stored in the controller are a plurality of different performance curves. When the transmission is in the low drive ratio, the controller selects a performance curve that comparatively increases the amount of torque and/or power the engine produces. When the transmission is in the high drive ratio, the controller selects a performance curve that comparatively reduces torque and/or power produced by the engine. Because the engine generates less heat when it produces less torque, the engine can accommodate additional emissions control devices and/or techniques that may otherwise adversely affect heat rejection.

Claims

1. A method of managing heat produced by an internal combustion system including an internal combustion engine coupled to a transmission, the method comprising:

monitoring an engaged drive ratio of a transmission during operation of an internal combustion system, the transmission including at least a low drive ratio and a high drive ratio;

storing in a controller a plurality of different performance curves including a first performance curve and a second performance curve, each performance curve selectable by the controller to operate the internal combustion engine;

selecting a performance curve from the plurality of different performance curves based in part on the engaged drive ratio monitored from the transmission;

operating the internal combustion engine in accordance with the performance curve selected;

wherein the first performance curve is selected when the transmission is engaged in the low drive ratio and the first performance curve increases torque output of the internal combustion engine;

and the second performance curve is selected when the transmission is engaged in the high drive ratio and the second performance curve reduces torque output of the internal combustion engine.

2. The method of claim 1, further comprising a step of cooling the internal combustion engine with a cooling system rated for engine operation under the second performance curve.

3. The method of claim 1, wherein the first performance curve and the second performance curve determines an amount of fuel supplied to the internal combustion engine.

4. The method of claim 1, wherein the first performance curve and the second performance curve map torque compared to engine speed.

5. A system for managing heat produced by an internal combustion engine, the system comprising:

an internal combustion engine;

a transmission coupled to the internal combustion engine, the transmission including a plurality of different engageable drive ratios;

a controller in communication with the transmission to monitor an engaged drive ratio, the controller storing a plurality of different performance curves including a first performance curve corresponding to comparatively increased torque output of the internal combustion engine and a second performance curve corresponding to comparatively reduced torque output of the internal combustion engine; and

a cooling system rated for cooling the internal combustion engine during operation under the second performance curve;

wherein during engine operation a performance curve selected by the controller is based in part upon the engaged drive ratio monitored in the transmission.

6. The system of claim 5, wherein the transmission includes at least a high drive ratio and a low drive ratio, the high drive ratio corresponding to the first performance curve and the low drive ratio corresponding to the second performance curve.

7. The system of claim 5, further comprising an exhaust system coupled to the internal combustion engine.

8. The system of claim 7, wherein the exhaust system includes at least one emissions control device restricting flow of exhaust gases.

9. The system of claim 8, wherein the emissions control device is selected from a group consisting of diesel particulate filters, catalytic convertors, and mufflers.

10. The system of claim 5, further comprising an exhaust gas re-circulation system re-circulating a portion of the exhaust gases back to the internal combustion engine.

11. The system of claim 5, wherein the first performance curve and the second performance curve map torque compared to engine speed.

12. The system of claim 5, further comprising a drive ratio control monitoring the engaged drive ratio of the transmission and communicating monitored information to the controller.

13. A method of enabling a vehicle to accommodate emissions controls comprising:

providing a vehicle including an internal combustion engine coupled to a transmission, the transmission including at least a high drive ratio and a low drive ratio;

installing on the vehicle at least one emissions control that adversely affects heat rejection from the internal combustion engine;

storing in a controller on the vehicle a plurality of different performance curves, each performance curve selectable by the controller to operate the internal combustion engine;

operating the internal combustion engine to propel the vehicle;

monitoring an engaged drive ratio of the transmission by the controller; and

selecting a performance curve for the controller to operate the vehicle from the plurality of different performance curves based in part on the engaged drive ratio monitored by the controller;

wherein the performance curve selected for the low drive ratio comparatively increases torque and the performance curve selected for the high drive ratio comparatively reduces torque.

14. The method of claim 13, wherein the emissions control is added to an exhaust system coupled to the internal combustion engine.

15. The method of claim 14, wherein the emissions control is selected from a group consisting of diesel particulate filters, catalytic convertors, and mufflers.

16. The method of claim 13, wherein the emissions control is an exhaust gas re-circulation system that re-circulates at least a portion of the exhaust gases back to the internal combustion engine.

17. The method of claim 13, wherein the plurality of different performance curves includes at least a first performance curve corresponding to the low drive ratio and a second performance curve corresponding to the high drive ratio.

18. The method of claim 17, further comprising a step of cooling the internal combustion engine with a cooling system rated for engine operation under the second performance curve.

19. The method of claim 13, wherein the controller monitors the engaged drive ratio of the transmission by a drive ratio control communicating with the controller and transmission.

20. The method of claim 13, wherein during operation under the second performance curve the controller reduces fuel injected to the internal combustion engine compared to during operation under the first performance curve.