ENGINE COOLING DEVICE

• US 20130213322A1
• Filed: 07/20/2011
• Published: 08/22/2013
• Est. Priority Date: 07/20/2011
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Takeuchi, Nobutaka
• Granted Patent: US 9,297,292 B2
• Time in Patent Office: Days
• US Class Current: 123/41.1
• CPC Class Codes: F01N 2240/02 a heat exchanger
• CPC Class Codes: F01N 2560/025 for measuring or detecting O2, e.g. lambda sensors
• CPC Class Codes: F01N 2560/06 the means being a temperature sensor
• CPC Class Codes: F01N 5/02 the devices using heat
• CPC Class Codes: F01P 2003/027 Cooling cylinders and cylinder heads in parallel
• CPC Class Codes: F01P 2007/146 using valves
• CPC Class Codes: F01P 2025/44 Outlet manifold temperature
• CPC Class Codes: F01P 2037/02 starting
• CPC Class Codes: F01P 2060/18 Heater
• CPC Class Codes: F01P 3/00 Liquid cooling
• CPC Class Codes: F01P 3/02 Arrangements for cooling cylinders or cylinder heads
• CPC Class Codes: F01P 7/162 by cutting in and out of pumps
• CPC Class Codes: F01P 7/164 by varying pump speed
• CPC Class Codes: F01P 7/165 characterised by systems with two or more loops
• CPC Class Codes: F02D 41/1494 Control of sensor heater
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

An engine cooling device including a water pump, a radiator, an exhaust heat recovery unit, and a coolant circulation circuit for circulating a coolant in these apparatuses includes a flow rate limiting means that limits the flow rate of the coolant that circulates in the exhaust heat recovery unit in the case where a temperature of a sensor element of an A/F sensor, that is disposed downstream of the exhaust heat recovery unit in an exhaust path, is below a preset activation temperature. An extent of opening of a second switching valve is made smaller in the case where the temperature of the sensor element is below the activation temperature than in the case where the temperature is equal to or higher than the activation temperature.

Claims

1. An engine cooling device comprising a water pump, a radiator, an exhaust heat recovery unit, and a coolant circulation circuit for circulating a coolant in these apparatuses,

the engine cooling device comprising a flow rate limiting means that limits a flow rate of the coolant that circulates in the exhaust heat recovery unit in a case where a temperature of a sensor element of an exhaust gas sensor that is disposed downstream of the exhaust heat recovery unit in an exhaust path is below a preset activation temperature.

2. The engine cooling device according to claim 1, wherein

the flow rate limiting means is a valve that is capable of regulating the flow rate of the coolant that circulates in the exhaust heat recovery unit, and makes an extent of opening of the valve smaller in a case where the temperature of the sensor element is below the activation temperature than in a case where the temperature is equal to or higher than the activation temperature.

3. The engine cooling device according to claim 1, wherein

the flow rate limiting means is a water pump that is capable of regulating the flow rate of the coolant that circulates in the exhaust heat recovery unit, and makes the amount of discharge of the water pump smaller in a case where the temperature of the sensor element is below the activation temperature than in a case where the temperature is equal to or higher than the activation temperature.

4. The engine cooling device according to claim 1, wherein

the exhaust heat recovery unit is disposed in a bypass path that bypasses a coolant path provided inside the engine.

5. The engine cooling device according to claim 1, wherein

coolant paths are each provided inside a cylinder block and a cylinder head of the engine and the coolant paths are disposed in parallel.

6. The engine cooling device according to claim 5, wherein

a supply of the coolant to the coolant path of the cylinder block is stopped when the engine is cold.

7. The engine cooling device according to claim 1, wherein

the flow rate limiting means stops a supply of the coolant to the exhaust heat recovery unit in a case where the temperature of the sensor element is below the activation temperature.

8. The engine cooling device according to claim 2, wherein

the exhaust heat recovery unit is disposed in a bypass path that bypasses a coolant path provided inside the engine.

9. The engine cooling device according to claim 3, wherein

the exhaust heat recovery unit is disposed in a bypass path that bypasses a coolant path provided inside the engine.

10. The engine cooling device according to claim 2, wherein

coolant paths are each provided inside a cylinder block and a cylinder head of the engine and the coolant paths are disposed in parallel.

11. The engine cooling device according to claim 3, wherein

coolant paths are each provided inside a cylinder block and a cylinder head of the engine and the coolant paths are disposed in parallel.

12. The engine cooling device according to claim 4, wherein

coolant paths are each provided inside a cylinder block and a cylinder head of the engine and the coolant paths are disposed in parallel.

13. The engine cooling device according to claim 8, wherein

coolant paths are each provided inside a cylinder block and a cylinder head of the engine and the coolant paths are disposed in parallel.

14. The engine cooling device according to claim 9, wherein

coolant paths are each provided inside a cylinder block and a cylinder head of the engine and the coolant paths are disposed in parallel.

15. The engine cooling device according to claim 2, wherein

the flow rate limiting means stops a supply of the coolant to the exhaust heat recovery unit in a case where the temperature of the sensor element is below the activation temperature.

16. The engine cooling device according to claim 3, wherein

the flow rate limiting means stops a supply of the coolant to the exhaust heat recovery unit in a case where the temperature of the sensor element is below the activation temperature.

17. The engine cooling device according to claim 4, wherein

the flow rate limiting means stops a supply of the coolant to the exhaust heat recovery unit in a case where the temperature of the sensor element is below the activation temperature.

18. The engine cooling device according to claim 5, wherein

the flow rate limiting means stops a supply of the coolant to the exhaust heat recovery unit in a case where the temperature of the sensor element is below the activation temperature.

19. The engine cooling device according to claim 6, wherein

the flow rate limiting means stops a supply of the coolant to the exhaust heat recovery unit in a case where the temperature of the sensor element is below the activation temperature.

20. The engine cooling device according to claim 14, wherein

a supply of the coolant to the coolant path of the cylinder block is stopped when the engine is cold.