Single-loop cooling system having dual radiators

• US 20090000779A1
• Filed: 06/29/2007
• Published: 01/01/2009
• Est. Priority Date: 06/29/2007
• Status: Abandoned Application

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Johnson, Kris William, Slone, Larry Michael, Evans, Timothy Alan, Hickam, Christopher Dale, Kothamachu, Kranthi Kumar
• Application Number:
  US11/819,883
• Publication Number:
  US 20090000779A1
• Time in Patent Office: Days
• US Class Current: 165/299
• CPC Class Codes: F01P 11/08 Arrangements of lubricant coolers in lubrication apparatus F01M
• CPC Class Codes: F01P 7/167 by adjusting the pre-set temperature according to engine parameters, e.g. engine load, engine speed
• CPC Class Codes: G05D 23/1931 to control the temperature of one space
• CPC Class Codes: G05D 23/24 the sensing element having a resistance varying with temperature, e.g. a thermistor

Abstract

A cooling system for use with a heat source is disclosed. The cooling system has an oil cooler, a fluid pump driving fluid through the cooling system, a first heat exchanger, and a first bypass line to direct fluid around the first heat exchanger. The cooling system also has a first electrically-controlled valve to selectively direct at least a portion of the fluid to at least one of the first heat exchanger and the first bypass line based on a fluid temperature. The cooling system further has a second heat exchanger, and a second bypass line to direct fluid around the second heat exchanger. The cooling system additionally has a second electrically-controlled valve located upstream of the oil cooler and configured to selectively direct at least a portion of the fluid to at least one of the second heat exchanger and the second bypass line based on an oil temperature.

Claims

1. A cooling system for use with a heat source, comprising:

an oil cooler;

a fluid pump configured to drive fluid through the cooling system;

a first heat exchanger;

a first bypass line configured to direct fluid from the heat source around the first heat exchanger;

a first electrically-controlled valve configured to selectively direct at least a portion of the fluid from the heat source to at least one of the first heat exchanger and the first bypass line based on a temperature of the fluid;

a second heat exchanger located downstream of and in series with the first heat exchanger;

a second bypass line configured to direct fluid around the second heat exchanger; and

a second electrically-controlled valve located upstream of the oil cooler and configured to selectively direct at least a portion of the fluid to at least one of the second heat exchanger and the second bypass line based on a temperature of oil.

2. The cooling system of claim 1, wherein the first electrically-controlled valve is configured to selectively direct at least a portion of the fluid to at least one of the first heat exchanger and the first bypass line further based on at least one of a temperature of the fluid exiting the heat source and a mechanical load of the heat source.

3. The cooling system of claim 2, further including a temperature sensor communicatively coupled with the first electrically-controlled valve and configured to generate and deliver a signal indicative of the temperature of the fluid exiting the heat source.

4. The cooling system of claim 1, wherein the second electrically-controlled valve is configured to selectively direct at least a portion of the fluid to at least one of the second heat exchanger and the second bypass line further based on at least one of a temperature of the fluid and a mechanical load of the heat source.

5. The cooling system of claim 1, further including a main bypass line configured to direct fluid around the second heat exchanger and the oil cooler.

6. The cooling system of claim 1, further including a temperature sensor communicatively coupled with the second electrically-controlled valve and configured to generate and a deliver a signal indicative of the temperature of the oil.

7. The cooling system of claim 1, wherein the first electrically-controlled valve is further configured to:

determine a desired fluid temperature range;

increase the amount of fluid directed to the first heat exchanger when the temperature of the fluid is greater than the desired fluid temperature range; and

decrease the amount of fluid directed to the first heat exchanger when the temperature of the fluid is less than the desired fluid temperature range.

8. The cooling system of claim 7, wherein the desired fluid temperature range is determined based on a mechanical load of the heat source.

9. The cooling system of claim 1, wherein the second electrically-controlled valve is further configured to:

determine a desired oil temperature range;

increase the amount of fluid directed to the second heat exchanger when the temperature of the oil is greater than the desired oil temperature range; and

decrease the amount of fluid directed to the second heat exchanger when the temperature of the oil is less than the desired oil temperature range.

10. The cooling system of claim 9, wherein the desired oil temperature range is determined based on a mechanical load of the heat source.

11. A method for managing the temperatures of a heat source and oil circulated through the heat source, comprising:

driving fluid through a main circuit;

selectively branching at least a portion of the fluid through at least one of a first branch and a second branch based on a temperature of the fluid;

cooling the fluid in the first branch;

joining the fluid from the first branch and the second branch;

selectively branching at least a portion of the fluid through at least one of a third branch and a fourth branch based on a temperature of the oil;

cooling the fluid in the third branch;

joining the fluid from the third branch and the fourth branch; and

cooling the oil.

12. The method of claim 11, wherein the step of cooling the oil includes transferring heat from the oil to the fluid.

13. The method of claim 11, wherein the step of selectively branching at least a portion of the fluid through at least one of a first branch and a second branch is based further on at least one of a temperature of the fluid exiting the heat source and a mechanical load of the heat source.

14. The method of claim 11, wherein the step of selectively branching at least a portion of the fluid through at least one of a third branch and a fourth branch is based further on at least one of a temperature of the fluid and a mechanical load of the heat source.

15. The method of claim 11, further including:

determining a desired fluid temperature range;

increasing the amount of fluid through the first branch when the temperature of the fluid is greater than the desired fluid temperature range; and

decreasing the amount of fluid through the first branch when the temperature of the fluid is less than the desired fluid temperature range.

16. The method of claim 15, wherein the desired fluid temperature range is determined based on a mechanical load of the heat source.

17. The method of claim 11, further including:

determining a desired oil temperature range;

increasing the amount of fluid through the third branch when the temperature of the oil is greater than the desired oil temperature range; and

decreasing the amount of fluid through the third branch when the temperature of the oil is less than the desired oil temperature range.

18. The method of claim 17, wherein the desired oil temperature range is determined based on a mechanical load of the heat source.

19. A cooling system, comprising:

an engine;

an oil cooler configured to cool oil circulated through the engine;

a fluid pump configured to drive fluid through the cooling system;

a first heat exchanger;

a first bypass line configured to direct fluid from the heat source around the first heat exchanger;

a first electrically-controlled valve configured to selectively direct at least a portion of the fluid from the heat source to at least one of the first heat exchanger and the first bypass line based on a temperature of the fluid exiting the engine;

a second heat exchanger located downstream of and in series with the first heat exchanger;

a second bypass line configured to direct fluid around the second heat exchanger; and

a second electrically-controlled valve located upstream of the oil cooler and configured to selectively direct at least a portion of the fluid to at least one of the second heat exchanger and the second bypass line based on a temperature of oil within the oil cooler.

20. The cooling system of claim 19, wherein the first electrically-controlled valve is configured to selectively direct at least a portion of the fluid to the first heat exchanger and the first bypass line further based on at least one of a temperature of the fluid and a mechanical load of the heat source.