JPH11350957A - Engine cooling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To significantly lessen the deterioration of the cooling performance of the condenser caused by the thermal effect of the radiator coolant in the engine cooling device equipped with an integrated heat exchanger. SOLUTION: This engine cooling device comprises: an integrated heat exchanger 10 comprising a radiator 13 whereto the coolant from an engine 27 is circulated and a condenser 11 whereto the coolant is circulated which are adjacently located and wherein a corrugate fin provided at the core portion of the radiator 13 and a corrugate fin provided at the core portion of the condenser 11 are integrally formed; and a thermostat 31 which opens when the temperature of the coolant from the engine 27 is at or greater than a predetermined temperature to let the coolant flow from the engine 27 to the radiator 13. In this engine cooling device, the temperature at or higher than the thermostat 31 opens is set to the temperature higher than the maximum outlet temperature of the coolant from the condenser 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine cooling apparatus provided with an integrated heat exchanger in which a radiator and a condenser are arranged adjacent to each other and a radiator and a corrugated fin arranged in the core of the condenser are shared.

[0002]

2. Description of the Related Art In recent years, a so-called integrated heat exchanger in which a cooling condenser is connected to the front of a radiator has been developed, and such an integrated heat exchanger is disclosed in, for example, Japanese Patent Application Laid-Open No. 1-247990. And the like are known. FIG. 5 shows an integrated heat exchanger of this type. In this integrated heat exchanger, a condenser 1 is arranged on a front surface of a radiator 2.

The capacitor 1 is formed by forming a core portion 4 between a pair of capacitor tanks 3 which are opposed to each other at a predetermined interval, and the radiators 2 are opposed to each other at a predetermined interval. The core part 4 is formed between a pair of radiator tanks 5. In this integrated heat exchanger, a tube 6 for a condenser and a tube 7 for a radiator are arranged in the core portion 4, and a wide corrugated fin 8 is brazed across the tubes 6 and 7. , Corrugated fins 8 are shared.

[0004]

However, in such a conventional integrated heat exchanger, since the corrugated fins 8 are used in common, the heat of the relatively high-temperature cooling water flowing through the radiator tube 7 can be reduced. However, there is a problem that the refrigerant is transmitted to the relatively low-temperature refrigerant flowing through the condenser tube 6 through the corrugated fins 8, and the cooling performance of the condenser 1 is reduced.

That is, for example, when the engine of the automobile is idling, the traveling wind does not flow into the core portion 4, so that the cooling performance of the condenser 1 and the cooling water of the radiator 2 decreases. When the engine is idling, the cooling speed of the radiator 2 with respect to the cooling water is relatively insignificant since the engine speed is low, and the cooling performance of the condenser 1 with respect to the refrigerant is a problem. When the heat of the cooling water of the radiator 2 is transmitted to the refrigerant of the condenser 1 through the, the cooling performance of the condenser 1 is extremely reduced.

The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide an engine cooling device capable of greatly reducing the deterioration of the cooling performance of a condenser due to the thermal influence of cooling water of a radiator. Aim.

[0007]

According to a first aspect of the present invention, there is provided an engine cooling device in which a radiator for circulating cooling water from an engine and a condenser for circulating a refrigerant are disposed adjacent to each other, and are disposed in a core portion of the radiator. An integrated heat exchanger formed integrally with a corrugated fin and a corrugated fin disposed on a core portion of the condenser; and a valve that opens when the temperature of the cooling water on the engine side is equal to or higher than a predetermined temperature. And a thermostat that circulates cooling water on the side of the radiator, wherein a valve opening temperature of the thermostat is set to a temperature equal to or higher than a maximum outlet temperature of the refrigerant from the condenser. And

(Function) In the engine cooling device of the first aspect, the valve opening temperature of the thermostat is set to a temperature equal to or higher than the highest temperature (maximum outlet temperature) among the outlet temperatures of the refrigerant flowing out of the condenser in various running modes of the vehicle. Is set. Then, for example, when the vehicle is traveling uphill, a large load acts on the engine, so that the temperature of the cooling water of the radiator becomes equal to or higher than the valve opening temperature of the thermostat,
Cooling water is circulated to the radiator side.

On the other hand, for example, when the engine of an automobile is idling, since the load hardly acts on the engine, the temperature of the cooling water of the radiator becomes a temperature lower than the valve opening temperature of the thermostat, and the cooling water flows to the radiator side. Circulation is stopped. At this time, since the traveling wind does not flow into the integrated heat exchanger, the temperature of the refrigerant in the condenser increases, but since the circulation of the cooling water to the radiator side is stopped, the temperature of the corrugated fin on the radiator side is reduced. And the heat of the refrigerant in the condenser is discharged to the radiator through the corrugated fins.

That is, when the engine is idling or the like, the temperature of the cooling water in the radiator becomes lower than the temperature of the refrigerant in the condenser, and the heat of the refrigerant in the condenser is discharged to the radiator through corrugated fins. Cooling performance is improved.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIGS. 1 and 2 show an embodiment of an engine cooling device according to the present invention. In this engine cooling device, the integrated heat exchanger 10 is configured by disposing the condenser 11 on the front of the radiator 13. As shown in FIG. 3, the capacitor 11 is configured by forming a core 17 between a pair of capacitor tanks 15 and 16 that are arranged facing each other at a predetermined interval.

The radiator 13 is provided with a pair of radiator tanks 19 and 20 which are opposed to each other at a predetermined interval.
A core portion 17 is formed between them. Core part 1
7 is provided with a condenser tube 21 and a radiator tube 23. These tubes 2
The wide corrugated fins 25 are brazed across 1 and 23, and the corrugated fins 25 are shared.

In this embodiment, the condenser tank 1
The tank 5 and the radiator tank 19, and the condenser tank 16 and the radiator tank 20 are made of aluminum and are integrally formed by extrusion. Also,
The condenser tanks 15 and 16 are formed in a cylindrical shape,
The radiator tanks 19 and 20 are formed in a rectangular cylindrical shape.

In this embodiment, as shown in FIG. 1, a cooling water inflow pipe 29 through which cooling water from an engine 27 flows is connected to a radiator tank 19 located above the radiator 13. . Cooling water inflow pipe 2
9 is provided with a thermostat 31. Also,
Radiator tank 2 located below radiator 13
0 is connected to a cooling water outflow pipe 33 for flowing out cooling water to the engine 27.

The cooling water outflow pipe 33 is provided with a water pump 35. A circulation pipe 37 branching from the upstream side of the thermostat 31 of the cooling water inflow pipe 33 and connected to the upstream side of the water pump 35 is disposed. Further, a branch pipe 39 branched from the circulation pipe 37 and connected to the cooling water outflow pipe 33 is provided.

The branch pipe 39 is provided with a heater core 41. In this embodiment, the valve opening temperature of the thermostat 31 is set to a temperature equal to or higher than the highest temperature (maximum outlet temperature) among the outlet temperatures of the refrigerant flowing out of the condenser 11 in various running modes of the vehicle. That is, FIG. 4 shows the relationship between the temperature of the cooling water at the outlet of the radiator 13 and the temperature of the refrigerant at the outlet of the condenser 11 due to the difference in the running mode of the vehicle. In each of the traffic congestion and IDL (idling) driving modes, the radiator outlet water temperature is sufficiently higher than the condenser outlet refrigerant temperature.

In the state 5 minutes after the start,
The radiator outlet water temperature is substantially equal to the condenser outlet refrigerant temperature. In FIG. 4, the condenser outlet refrigerant temperature is highest at about 67 ° C. in the IDL mode, but in this embodiment, the valve opening temperature of the thermostat 31 is set to 80 ° C.

In the above-described engine cooling device, for example,
When the vehicle travels uphill, a large load acts on the engine 27, so that the temperature of the cooling water of the radiator 13 becomes 80 ° C. or higher, which is the valve opening temperature of the thermostat 31, as shown in FIG. The cooling water is circulated to the radiator 13 side. On the other hand, for example, when the engine 27 of the vehicle is idling or the like, since the load hardly acts on the engine 27, the temperature of the cooling water of the radiator 13 may be lower than the valve opening temperature of the thermostat 31 of 80 ° C. At this time, the thermostat 31 is closed, and the circulation of the cooling water to the radiator 13 is stopped as shown in FIG.

At this time, since the traveling wind does not flow into the integrated heat exchanger 10, the temperature of the refrigerant in the condenser 11 increases, but since the circulation of the cooling water to the radiator 13 is stopped, the radiator The temperature of the corrugated fin 25 on the 13 side is low, and the heat of the refrigerant in the condenser 11 is discharged to the radiator 13 side via the corrugated fin 25.

That is, in the above-described engine cooling device, the valve opening temperature of the thermostat 31 is controlled by the condenser 11.
Is set to a temperature equal to or higher than the highest temperature among the outlet temperatures of the refrigerant flowing out of the radiator 13 when the engine 27 is idling or the like.
1 becomes lower than the temperature of the refrigerant, and the amount of heat of the refrigerant in the condenser 11 is reduced via the corrugated fin 25 to the radiator 13.
And the cooling performance of the condenser 11 due to the thermal influence of the cooling water of the radiator 13 can be significantly reduced as compared with the related art.

On the other hand, the valve opening temperature of the thermostat 31 is
When the temperature is set to a temperature lower than the maximum outlet temperature of the refrigerant, for example, 65 ° C., as is clear from FIG. 4, the thermostat 31 is always opened at the time of idling of the automobile or the like, and the cooling water is circulated to the radiator 13. Therefore, the above effects cannot be obtained. In the above-described embodiment, the radiator tank 19 and the condenser tank 1
5 and an example in which the present invention is applied to an integrated heat exchanger in which the radiator tank 20 and the condenser tank 16 are integrated, but the present invention is not limited to such an embodiment. The present invention can also be applied to an integrated heat exchanger in which the tank and the condenser tank are separate bodies.

[0023]

As described above, in the engine cooling device of the first aspect, the valve opening temperature of the thermostat is set to a temperature equal to or higher than the highest temperature among the outlet temperatures of the refrigerant flowing out of the condenser. The deterioration of the cooling performance of the condenser due to the thermal influence of the cooling water can be greatly reduced as compared with the conventional case.

[Brief description of the drawings]

FIG. 1 is a piping diagram showing one embodiment of an engine cooling device of the present invention.

FIG. 2 is a piping diagram showing a state where a thermostat of the engine cooling device of FIG. 1 is closed.

FIG. 3 is a sectional view showing the integrated heat exchanger of FIG. 1;

FIG. 4 is an explanatory diagram showing a relationship between a radiator outlet water temperature and a condenser outlet refrigerant temperature in various running modes of an automobile equipped with the engine cooling device of FIG. 1;

FIG. 5 is a cross-sectional view showing a conventional integrated heat exchanger.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Integrated heat exchanger 11 Condenser 13 Radiator 17 Core part 25 Corrugated fin 27 Engine 31 Thermostat

Claims (1)

[Claims] A radiator (13) for circulating cooling water from an engine (27) and a condenser (11) for circulating a refrigerant are arranged adjacent to each other, and are provided on a core portion (17) of the radiator (13). Corrugated fins to be arranged (25)
An integrated heat exchanger (10) integrally formed with a corrugated fin (25) disposed on a core (17) of the condenser (11); and a temperature of cooling water on the engine (27) side. Is opened when the temperature is equal to or higher than a predetermined temperature, and a thermostat (3) that circulates the cooling water on the engine (27) side to the radiator (13) side.
An engine cooling apparatus comprising: (1) an engine cooling device, wherein the valve opening temperature of the thermostat (31) is set to a temperature equal to or higher than the maximum outlet temperature of the refrigerant from the condenser (11). Cooling system.