Vehicle cooling system

• US 20060196634A1
• Filed: 01/24/2006
• Published: 09/07/2006
• Est. Priority Date: 02/18/2005
• Status: Active Grant

• Current Assignee: Calsonic Kansei Corporation, Nissan Motor Co., Ltd.
• Original Assignee: Calsonic Kansei Corporation, Nissan Motor Co., Ltd.
• Inventors: Ishikawa, Takayuki, Iwasaki, Mitsuru, Sato, Yousuke
• Granted Patent: US 7,775,268 B2
• Time in Patent Office: Days
• US Class Current: 165/41
• CPC Class Codes: B60H 1/00885 Controlling the flow of heating or cooling liquid, e.g. valves or pumps B60H1/00899 takes precedence; constructions of valves B60H1/00485
• CPC Class Codes: B60H 1/00892 Devices specially adapted for avoiding uncomfortable feeling, e.g. sudden temperature changes B60H1/00885 takes precedence

Abstract

A vehicle cooling system comprises a vehicle unit, a heat exchanger, a cooling fan, a coolant pump, a three-way valve, and a control unit. The heat exchanger is arranged in the coolant route to selectively receive a coolant from the coolant outlet of the vehicle unit. The cooling fan is arranged to blow cooling air to the heat exchanger. The coolant pump is arranged to circulate the coolant through the coolant route. The three-way valve is arranged to switch the coolant route between a heat exchanger route that passes through the heat exchanger and a bypass route that bypasses the heat exchanger. The control unit is configured to control operation of at least one of the cooling fan, the three-way valve and the coolant pump based on a temperature of the coolant at the heat exchanger and a temperature of the coolant at the coolant outlet of the vehicle unit.

Claims

1. A vehicle cooling system comprising:

a vehicle unit having a coolant outlet and a coolant inlet with a coolant route therebetween;

a heat exchanger configured and arranged in the coolant route to selectively receive a coolant from the coolant outlet of the vehicle unit;

a cooling fan configured and arranged to blow cooling air to the heat exchanger;

a coolant pump configured and arranged to circulate the coolant through the coolant route; and

a three-way valve configured and arranged to switch the coolant route between a heat exchanger route that passes through the heat exchanger and a bypass route that bypasses the heat exchanger;

a control unit configured to control operation of at least one of the cooling fan, the three-way valve and the coolant pump based on a temperature of the coolant at the heat exchanger and a temperature of the coolant at the coolant outlet of the vehicle unit.

2. The vehicle cooling system recited in claim 1, wherein

the control unit is configured to control a flow rate of the coolant flowing into the heat exchanger based on the temperature of the coolant at the heat exchanger and the temperature of the coolant at the coolant outlet of the vehicle unit.

3. The vehicle cooling system recited in claim 1, wherein

the control unit is configured to control operation of at least one of the three-way valve and the coolant pump so that a flow rate of the coolant flowing into the heat exchanger is adjusted based on the temperature of the coolant at the heat exchanger and the temperature of the coolant at the coolant outlet of the vehicle unit.

4. The vehicle cooling system recited in claim 1, wherein

the control unit is configured to electrically control an opening speed of the three-way valve with which the coolant route is switched from the bypass route to the heat exchanger route.

5. The vehicle cooling system recited in claim 4, wherein

the control unit is configured to control the opening speed of the three-way valve to switch the coolant route from the bypass route to the heat exchanger route such that the larger a difference between the temperature of the coolant at the coolant outlet of the vehicle unit and the temperature of the coolant at the heat exchanger is, the slower the opening speed of the three-way valve becomes.

6. The vehicle cooling system recited in claim 1, wherein

the control unit is configured to electronically control a rotational speed of the coolant pump.

7. The vehicle cooling system as recited in claim 1, wherein

the control unit is configured to electronically control a rotational speed of the coolant pump and a rotational speed of the cooling fan simultaneously.

8. The vehicle cooling system as recited in claim 1, wherein

the control unit is configured to control an amount of the cooling air passing across the heat exchanger.

9. The vehicle cooling system as recited in claim 1, wherein

the control unit is configured to increase a rotational speed of the cooling fan before the three-way valve switches the coolant route from the bypass route to the heat exchanger route.

10. The vehicle cooling system as recited in claim 9, wherein

the control unit is further configured to adjust the rotational speed of the cooling fan based on an increase rate of the temperature of the coolant at the coolant outlet of the vehicle unit.

11. The vehicle cooling system as recited in claim 1, wherein

the control unit is configured to control a rotational speed of the cooling fan based on a traveling speed of a host vehicle.

12. The vehicle cooling system as recited in claim 1, wherein

the control unit is configured to simultaneously control a flow rate of the coolant flowing into the heat exchanger and an amount of the cooling air passing across the heat exchanger.

13. The vehicle cooling system as recited in claim 1, wherein

the control unit is configured to use an outside air temperature as the temperature of the coolant at the heat exchanger.

14. The vehicle cooling system as recited in claim 1, further comprising

an additional heat exchanger integrally coupled to the heat exchanger to form a heat exchanger unit.

15. The vehicle cooling system as recited in claim 1, wherein

the control unit is further configured to control the operation of the at least one of the cooling fan, the three-way valve and the coolant pump based on the temperature of the coolant at the coolant outlet of the vehicle unit and a difference between the temperature of the coolant at the coolant outlet of the vehicle unit and the temperature of the coolant at the heat exchanger.

16. The vehicle cooling system as recited in claim 15, wherein

the control unit is further configured to control the operation of the at least one of the cooling fan, the three-way valve and the coolant pump based on a traveling speed of a host vehicle when the temperature of the coolant at the coolant outlet of the vehicle unit is equal to or larger than a prescribed temperature and the difference between the temperature of the coolant at the coolant outlet of the vehicle unit and the temperature of the coolant at the heat exchanger is larger than a prescribed value.

17. The vehicle cooling system as recited in claim 16, wherein

the control unit is further configured to adjust a rotational speed of the cooling fan based on an increase rate of the temperature of the coolant at the coolant outlet of the vehicle unit when the traveling speed of the host vehicle is lower than a predetermined speed.

18. The vehicle cooling system as recited in claim 17, wherein

the control unit is further configured to increase the rotational speed of the cooling fan before the three-way valve switches the coolant route from the bypass route to the heat exchanger route.

19. A vehicle cooling method comprising:

providing a coolant route that circulates a coolant between a vehicle unit and a heat exchanger;

detecting a temperature of the coolant at the heat exchanger and a temperature of the coolant at a coolant outlet of the vehicle unit; and

controlling at least one of a flow rate of the coolant flowing into the heat exchanger and an amount of cooling air passing across the heat exchanger based on the temperature of the coolant at the heat exchanger and the temperature of the coolant at a coolant outlet of the vehicle unit.

20. A vehicle cooling system comprising:

heat exchanging means for cooling a coolant that has been warmed by a vehicle unit;

coolant circulating means for circulating the coolant between the vehicle unit and the heat exchanging means;

controlling means for controlling at least one of a flow rate of the coolant flowing into the heat exchanging means and an amount of cooling air passing across the heat exchanging means based on the temperature of the coolant at the heat exchanging means and the temperature of the coolant at a coolant outlet of the vehicle unit.