JP2894033B2 - Cooling system for internal combustion engine for vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to cooling of a water-cooled internal combustion engine for a vehicle, and more particularly to a cooling system for a vehicle in which the cooling capacity of cooling water and the cooling capacity of a cooling device can be controlled in accordance with the operating condition of the vehicle. The present invention relates to a cooling device for a water-cooled internal combustion engine.

[0002]

2. Description of the Related Art As shown in FIG. 14, in a vehicle equipped with an internal combustion engine (engine) 94, a radiator 92 for circulating the cooling water of the engine 94 is normally disposed in front of the vehicle body, and behind the radiator 92. A cooling fan 93 as cooling air introduction means is disposed in the cooling fan. Then, the airflow accompanying the traveling of the vehicle and the airflow generated by the cooling fan 93 are supplied to the radiator 92 to promote heat exchange in the radiator 92. In a vehicle equipped with a cooling device, a condenser (condenser) 81 for condensing the circulating refrigerant is disposed upstream of the air flow of the radiator 92 (see Japanese Utility Model Application Laid-Open No. 62-6422). The air that has passed through the condenser 81 is guided to a radiator 92. During the cooling operation of the cooling device, a high-temperature refrigerant compressed by a compressor is guided to the condenser 81, and the refrigerant is cooled, condensed and liquefied by exchanging heat with the supplied air.

Therefore, the cooling air 901 generated by the air flow generated by the running of the vehicle and the air flow generated by the operation of the cooling fan is heated when passing through the condenser 81 to which the high-temperature refrigerant is supplied. You. Then, the heated cooling air 901 is guided to a radiator 92 arranged behind the condenser 81. And this 9
The engine 94 circulates through the cooling water 2 to cool the engine 94 to an appropriate temperature. In FIG. 14, reference numeral 95 denotes a hood, 96 denotes a grill, and 97 denotes a bumper.

[0004] In recent years, a cooling device mounted on a vehicle has a large capacity cooling device in order to improve a comfortable cooling effect. In addition, the amount of heat generated by the engine increases as the output of the vehicle increases, and the engine room tends to become denser as the number of accessories increases. Furthermore, with the adoption of slant nose in the vehicle body design, the cooling wind is significantly reduced by the vehicle speed.

In particular, when the vehicle is climbing at a low speed as described below, the heat generated by the engine is large and sufficient wind speed cannot be expected. On the other hand, an increase in the cooling capacity is required to improve the cooling effect in the vehicle interior. . Therefore, the temperature of the cooling air that passes through the condenser 81 and is introduced into the radiator 92 increases significantly. Therefore, the cooling capacity of the cooling water of the radiator 92 is reduced, and the engine 94 may be overheated. In order to solve this, for example, when the cooling water temperature exceeds 100 ° C., a method of forcibly stopping the cooling device is adopted, or the radiator is enlarged, and the capacity of the cooling fan 93 is increased. Have been.

[0006]

However, there is a problem that when the cooling device is forcibly stopped, the comfort in the vehicle compartment is impaired. Also, due to the limited space of the vehicle, the radiator and cooling fan will be larger,
It is difficult to increase the capacity. On the other hand, in a driving situation in which no vehicle speed wind can be expected, such as during idling, the amount of cooling air guided to the condenser 81 is small.
The heat radiation performance from No. 1 deteriorates. As a result, the refrigerant pressure at the outlet of the compressor increases, and the power consumption of the compressor increases, which contributes to the deterioration of fuel efficiency in summer.

The present inventors have therefore started to analyze the ventilation system of a vehicle in order to address the above problems. That is, first,
Observation of the flow of cooling air in the engine room, as shown in FIG.
As indicated by an arrow 941 in FIG. 14 , it has been found that the air once heated and exchanged by the radiator 92 flows between the condenser 81 and the radiator 92 from the engine 94 side and flows into the radiator 92 again. Therefore,
Although the amount of cooling air sent by the cooling fan 93 has completely passed through the radiator 92, the amount of cooling air passing through the condenser 81 is expected to be considerably smaller than the amount of air flowing through the radiator 92 due to the aforementioned wraparound backflow. You.

Therefore, the radiator 92 and the capacitor 81
A number of hot-wire anemometers were placed in front of the to measure the amount of wind that actually passed. As a result, it was found that the amount of wind passing through the condenser 81 was about 35% smaller than the amount of wind passing through the radiator 93 during idling. The tendency is similar during low-speed uphill running, but the difference decreases as the vehicle speed increases.

Further, since the amount of air passing through the condenser 81 decreases, the temperature of the air passing through the condenser 81 rises remarkably. In addition, it has been found that the temperature of the inlet air of the radiator 92 increases due to the wind flowing backward from the engine room, and the cooling water is not sufficiently cooled. SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-described conventional problems, and has been made to improve the cooling capacity of a cooling device, reduce the power consumption of a compressor, and improve the cooling efficiency of a radiator so that there is no danger of overheating of an internal combustion engine. It is an object of the present invention to provide a cooling device for a water-cooled internal combustion engine.

[0010]

According to the present invention, there is provided a condenser for condensing a refrigerant of a cooling device, a radiator disposed rearward of the condenser in a vehicle traveling direction to cool a cooling water of an internal combustion engine, and a radiator from a condenser side to a radiator side. Means for introducing cooling air, bypass means for opening and closing a bypass path to the radiator by bypassing the condenser, and air between the condenser and the radiator when the bypass path is released. A fixed plate that divides into a main air passage that passes through the radiator and a sub air passage that bypasses the condenser and flows to the radiator, and is provided around the space between the condenser and the radiator, and wraps heated air from the internal combustion engine side And a control means for driving and controlling the bypass passage opening / closing means in accordance with the state of the heat load of the internal combustion engine. In the cooling device of the water-cooled internal combustion engine for a vehicle, characterized in that it includes. The most remarkable point in the present invention is that a bypass passage opening / closing means is provided in the bypass passage, a fixed plate for separating the two types of air passages is provided in a space between the condenser and the radiator, and a surrounding space between the condenser and the radiator is provided. Is provided with a blocking plate,
The detour passage opening / closing means is configured to be driven and controlled by the control means.

As the bypass passage opening / closing means, for example, a plate-shaped damper is used. The bypass passage opening / closing means is means for introducing cooling air to a part of the radiator without passing through (ie, bypassing) the condenser. As a part of the radiator, there is a lower portion of the radiator (FIG. 1) or one or both of the side portions (FIG. 7). Therefore, the bypass passage opening / closing means is provided at the upper and lower ends, side ends, and the like of the radiator so as to be openable / closable.

Next, the fixing plate is a fixing plate that partitions the space between the condenser and the radiator in, for example, the vertical direction or the horizontal direction. And the fixing plate is
Adjusting the pressure balance between the main air passage flow and the sub air passage flow by dividing the main air passage that flows to the radiator through the condenser and the sub air passage that flows from the bypass passage to the radiator without passing through the condenser In addition, it is a fixing plate that allows the air flow rate of the main air passage and the sub air passage to be set. That is, it is possible to set the pressure balance, the flow rate of the passing air, and the like based on the position and angle of the fixed plate.

For example, the fixing plate is preferably provided such that the sub air passage occupies 20 to 50% of the entire area of the front surface of the radiator. If it is less than 20%, the amount of cooling air in the sub air passage based on the bypass passage is small, and the cooling capacity of the radiator may be reduced. On the other hand, if it exceeds 50%, the amount of cooling air in the main air passage is small, the heat radiation performance of the condenser is deteriorated, the power consumption of the compressor is increased, and the fuel efficiency may be deteriorated.

The above-mentioned shut-off plate is provided around the space between the condenser and the radiator, and is a plate for shutting off (backflow) of heated air from the internal combustion engine side. The blocking plate and the fixed plate form the main air passage in a state surrounded by a cylinder. Also,
The sub air passage is formed in a state surrounded by a fixed plate, a blocking plate, and an openable / closable bypass passage opening / closing means.

The control means detects the thermal load state of the internal combustion engine, opens and closes the bypass passage opening / closing means, and adjusts the amount of cooling air in the sub air passage. The detection of the heat load is performed, for example, by detecting the temperature of the cooling water of the internal combustion engine. The drive control means of the bypass passage opening / closing means includes an actuator using negative pressure, an actuator using electric or hydraulic pressure, and the like.

[0016]

In the cooling device according to the present invention, the control means controls the opening / closing of the bypass passage opening / closing means in accordance with the state of the heat load of the internal combustion engine, specifically, the temperature state of the cooling water. That is, for example, under daily running conditions, the bypass passage opening / closing means is in a closed state, and the vehicle speed wind and the cooling wind introduced by the cooling fan all flow into the radiator after passing through the condenser. Therefore, the cooling efficiency of the condenser is improved, and the cooling capacity of the cooling device is improved.

On the other hand, when the heat load of the internal combustion engine is rising, such as under extremely severe low-speed uphill driving conditions, the rise of the cooling water temperature is detected and the bypass passage opening / closing means is opened. For this reason, in addition to the cooling air flow (main air passage) passing through the condenser, the cooling air flow (sub air passage) is directly introduced from the bypass passage to the radiator. As a result, the air volume passing through the radiator can be increased, and at the same time, the air outside the vehicle can be guided to the radiator at a low temperature, and the cooling water can be efficiently cooled. A blocking plate is provided around the condenser and the radiator to prevent heated air from flowing from the internal combustion engine. Therefore,
The cooling efficiency of the radiator can be further improved.

Further, as described above, with the improvement of the cooling performance of the condenser, that is, the improvement of the cooling performance of the cooling device, the high pressure side pressure of the compressor is reduced due to the balance of the air conditioner cycle, and the power consumption is reduced. Further, especially when the heat load of the internal combustion engine is large, the cooling efficiency of the cooling water of the radiator can be improved, so that there is no risk of overheating of the internal combustion engine. Therefore, according to the present invention, there is provided a cooling device for a water-cooled internal combustion engine for a vehicle, in which the power consumption of a compressor can be reduced while improving the performance of a cooling device, and there is no risk of overheating of the internal combustion engine while improving the cooling efficiency of a radiator. Can be provided.

[0019]

【Example】

First Embodiment A cooling device for an internal combustion engine for a vehicle according to an embodiment of the present invention will be described with reference to FIGS. The cooling device in this example is
As shown in FIG. 1, a condenser 81 for condensing the refrigerant of the cooling device, a radiator 92 arranged rearward of the condenser 81 in the vehicle traveling direction to cool the cooling water of the internal combustion engine 94, and a radiator 92 from the condenser 81 side Means (cooling fan 93) for introducing cooling air toward the side.

The cooling device includes a bypass passage 15 bypassing the condenser 81 to the radiator 92 and a damper 1 serving as a bypass passage opening / closing means for opening / closing the bypass passage 15.
0, a fixed plate 2 for partitioning between the main air passage A1 and the sub air passage B1, and a cutoff provided around the condenser 81 and the radiator 92 for blocking the flow of heated air from the internal combustion engine 94 side. And a plate 3. Further, it has a negative pressure type actuator 11 as control means for controlling the drive of the damper 10 in accordance with the state of the heat load of the internal combustion engine 94. The main air passage A1 is a passage for cooling air flowing through the condenser 81 to the radiator 92, and the sub air passage B1 is a passage for cooling air flowing to the radiator 92 bypassing the condenser 81. Others
This is the same as the conventional example (FIG. 14) .

As shown in FIG. 3, the blocking plate 3 is a rectangular frame plate disposed between the condenser and the radiator, and includes a top plate 31 and side plates 32. Further, a fixing plate 2 is provided below the central portion. Below the fixed plate 2, both side plates 3
Between shafts 2 and 32, a shaft 101 is rotatably suspended,
The damper 10 is fixed to the shaft 101.

An actuator 11 is connected to the lower surface of the damper 10. Further, a spring 12 is provided between the damper 10 and the fixed plate 2 so as to constantly urge the damper 10 in the release direction. The top plate 31 and the side plate 32 are provided with brackets 35 for fixing the blocking plate 3 to the radiator. The fixing plate 2 is provided at a position below about 40% of the height of the radiator 92.

Next, FIG. 4 shows a configuration of a cooling water circulation system and a cooling system of a cooling device (air conditioner). As shown in the figure, the cooling water of the engine 94 is circulated by the pump 921 and supplied to the radiator 92. Note that a water temperature sensor 922 is provided in the water passage circuit to detect a cooling water temperature representing the heat load of the engine 94. In the cooling device mounted on this vehicle, the compressor 85
Is supplied to the condenser 81 via the refrigerant circuit 80 and is condensed and liquefied. The liquefied refrigerant is supplied to the evaporator 84 via the receiver 82 and the expansion valve 83.

Then, the air passing through the evaporator 84 is cooled. The air thus cooled is discharged into the vehicle interior. Also, the refrigerant of the evaporator 84 is
It is returned to the compressor 85. Here, the expansion valve 83 is a temperature-sensitive cylinder 87 for detecting the state of the refrigerant at the outlet of the evaporator 84, for example, the refrigerant temperature.
It is controlled according to the gas pressure change inside. The actuator 11 is connected to a negative pressure valve 89.
Therefore, when a negative pressure is introduced into the actuator 11 through the negative pressure valve 89, the damper 10 is turned to the open position against the urging force of the spring 12.

The cooling fan of this embodiment is controlled by a control circuit 7 of an electronic control unit constituted by a microcomputer or the like. The control circuit (ECU) 7 includes a rotation speed signal from the engine rotation speed sensor 74, a cooling water temperature signal from the cooling water temperature sensor 922,
A temperature signal from a temperature sensor 81 for detecting a cooling air blowing temperature of the evaporator 84, a pressure signal from a pressure sensor 73 for detecting a refrigerant pressure of the compressor 85, and the like are input. Then, the control circuit 7 controls the electric motor of the cooling fan 93 , the negative pressure switching valve 89 of the actuator 11, the compressor 85, the evaporator blower fan (not shown), and the like.

Next, the operation of the present embodiment will be described with reference to the flowchart shown in FIG. First, under daily driving conditions, the damper 10 is in the closed position as shown by the broken lines in FIGS. 1 and 4 (step 201). At this time, the vehicle speed wind and the cooling wind A guided by the cooling fan 93 all pass through the condenser 81 and then pass through the radiator 9.
2 (step 202). That is, the cooling air A is
Regardless of the fixed plate 2, the light passes through the entire surface of the capacitor 81 and passes through the entire surface of the radiator 92. Since there is no air flow bypassing the condenser 81 and directly entering the radiator 92, and there is no heated air flowing from the engine 94 side, the amount of cooling air passing through the condenser 81 is about the same as that of the conventional device at idle. Increase by 30%.

As described above, since the amount of cooling air to the condenser 81 is increased, when the air conditioner is used in summer, the heat radiation characteristics of the condenser 81 alone are improved. for that reason,
Due to the balance characteristics of the cooler cycle, the indoor cooling capacity is improved, and the discharge pressure of the compressor 85 is reduced. As a result, the power consumption of the compressor can be reduced. In addition, according to experiments performed by the inventors of the present invention, it has been found that during idling in summer, the cooling capacity can be increased by 5% and the power consumption of the compressor can be reduced by 9%. In addition, the influence on the cooling water temperature is that the radiator heat radiation amount is reduced and the air-water temperature difference is increased due to a decrease in the radiator passing air flow.

However, due to the increase in the amount of air passing through the condenser, the temperature of the cooling air heated by the condenser 81 is greatly reduced, and the temperature of the inlet air to the radiator 92 is decreased. Therefore, the temperature of the cooling water can be further reduced as compared with the conventional device. On the other hand, when the temperature of the cooling water Tw rises during traveling on an extremely severe low-speed climb and exceeds a predetermined value (for example, 100 ° C.) (steps 203 and 204), the water temperature sensor 9
At 22, a cooling water temperature signal is transmitted to the control circuit 7 , and the negative pressure switching valve 89 is opened. As a result, the diaphragm type actuator 11 is operated, and the damper 10 is opened against the urging force of the spring 12 (step 20).
5).

For this reason, as shown in FIGS. 1, 2 and 4, the cooling air B of the high temperature from the traveling direction of the vehicle is guided from the bypass passage 15 directly to the lower part of the radiator 92 as shown by the arrow. (Auxiliary air passage B1). Note that the capacitor 81
The cooling air A is directed (main air passage A1) as shown by an arrow (step 206). Therefore, the cooling air passing through the radiator 92 is the sum of the cooling air A and the cooling air B having a lower temperature than the cooling air A, and is significantly larger than the cooling air only when the damper 10 is in the closed state. Therefore, the cooling performance of the radiator 92 is improved. At this time, the cooling air tries to enter the sub air passage B1 from the lower part of the condenser 81 (below the fixed plate 2).
The volume of the air is controlled by the flow of cooling air passing through the lower part of the condenser 81.
The ventilation resistance of the cooling air entering from the bypass passage 15
Pass through the lower part of the capacitor 81
The air volume is very small.

On the other hand, in the condenser 81, the cooling air A passing through the condenser 81 is lower than the cooling air flow when the damper 10 is closed, and the temperature rise of the air in the condenser 81 is increased. However, from the vehicle traveling direction, the low temperature of the cooling air B introduced via bypass passage 15 is Ri Do the inlet air temperature below the radiator 92, further cooling air amount increases. Therefore, the average inlet air temperature at the front of the radiator 92 is lower than when the damper 10 is in the closed position. Therefore, the heat radiation amount of the cooling water increases, and the cooling water temperature can be reduced. According to experiments performed by the inventors of the present invention, it has been confirmed that a passenger car with a displacement of 2000 cc improves cooling performance by about 10%.

The radiator 92 into which the cooling air B flows
, That is, the area of the air passage of the sub air passage B1 (the area of the radiator from the lower end surface of the radiator 92 to the fixed plate 2) is preferably not more than half of the entire front area of the radiator 92. This means that the capacitor 8
1 and the radiator 92, and the shape of the front end of the vehicle. And, the larger the area of the inlet of the air passage through which the cooling air B flows into the radiator 92, the smaller the amount of the cooling air A passing through the condenser 81. In addition, the passage area of the sub air passage B1 means that under low speed uphill conditions, which are the most severe for the cooling water temperature, the engine speed is high, the amount of refrigerant discharged by the compressor is large, and the cooling capacity is sufficient. Since the decrease of the cooling air A due to the decrease increases the power consumption of the compressor, it is desirable to determine the reduction based on the balance.

As shown in FIGS. 1 and 2, the damper 1
0 is closed, the cooling air A
Through the main air passage A1 above the fixed plate 2
And the auxiliary air passage B between the fixed plate 2 and the damper 10
1 also passes through the radiator 92. On the other hand, when the damper 10 is opened, the cooling air A flows through the main air passage A1.
Through the sub air passage B1 and almost the bypass passage 15
Cooling air B flows from the inside. This is because the ventilation resistance is large in the condenser 81, but the bypass path has no ventilation resistance.

In the present embodiment, the ratio of the inlet area of the cooling air B (the area of the sub air passage B1) to the entire front area of the radiator 92 is set to about 40%. This is due to the amount of air passing through the condenser 81 in the conventional device and the damper 1 in this embodiment.
The flow rate of the cooling air A when 0 is released is set to be substantially the same. Therefore, the cooling water can be efficiently cooled without any reduction in the air-conditioning capacity. Further, the radiator 92 of this embodiment is of a vertical flow type, in which cooling water from the engine 94 is circulated from the upper tank of the radiator through the tube of the core portion, flows to the lower tank, and returns to the engine.

In this case, a description will be given from the viewpoint of temperature efficiency for judging whether the heat radiation characteristic of the radiator is good or not.
It can be seen that it is better to guide the cooling air B to the lower part of the cooling water 2, that is, the downstream side in the core of the cooling water. As described above, in the daily running condition range, the air-conditioning capacity is given priority, and the cooling capacity can be improved, and the vehicle fuel efficiency can be improved by reducing the power consumption of the compressor.

Also, in the rarely occurring summer low-speed uphill traveling condition area, the damper 10 is opened when a predetermined water temperature level is reached, so that the radiator cooling performance can be actively increased to overheat the engine. Can be prevented. In this example, the blocking plate 3 is a capacitor 81
Although it is provided between the radiator 92 and the radiator 92, it is also possible to extend the blocking plate 3 toward the front in the traveling direction of the vehicle, and provide a wind guide duct from immediately after the grill of the vehicle to the condenser 81.

Next, in the cooling device, the cooling water is
An example of control of the cooling device when the temperature exceeds 05 ° C. will be described.
This will be described with reference to the flowchart of FIG. That is,
In this example, the air conditioner capacity is more positively controlled with the damper 10 in the open state (200 to 206 as in FIG. 5). That is, when the cooling water temperature is high (step 301), such as when the cooling water temperature exceeds a second set value (for example, 105 ° C.), the engine speed is high and the air conditioner cooling capacity has a sufficient margin.

For this reason, the blower voltage is controlled in order to reduce the blowing capacity of the evaporator (step 30).
2) Perform variable capacity control of the variable capacity compressor (step 303). In addition, the amount of circulating refrigerant is controlled by bypassing the refrigerant from the compressor discharge side to the suction side (step 304). Further, when the intake air to the evaporator is introduced from outside air, the mode is forcibly switched to the vehicle interior circulation mode. Switching control (step 305) is performed. These controls are performed individually or in whole. By performing such control, the temperature of the cooling water can be further reduced.

Embodiment 2 In this embodiment, as shown in FIGS. 7 and 8, the bypass path 15 is provided on both sides of the condenser 81 and the radiator 92. That is, blocking plates are provided on the upper and lower surfaces of the outer periphery of the capacitor 81 and the radiator 92 (not shown).
Dampers 10 are provided on both sides of the blocking plate so as to be openable and closable. An actuator 11 is connected to the damper 10. Two fixed plates 2 are provided in the vertical direction between the capacitor 81 and the radiator 92.
Others are the same as the first embodiment. Therefore, a main air passage A1 is formed between the fixed plates 2 and 2, and a sub air passage B1 is formed between the fixed plate 2 and the damper 10 on both sides. Note that the damper 10 can be provided on only one side. Also in this example, the first embodiment
The same operation and effect as described above can be obtained.

Embodiment 3 In this embodiment, as shown in FIGS. 9 to 11, the cross-sectional shapes of various fixed plates 2 interposed between a capacitor 81 and a radiator 92 and their arrangements are shown. FIG. 9 shows a stationary plate 201 having a streamline along the cooling air flow. Thereby, the flow of the cooling air on the upper and lower surfaces of the fixed plate 201 becomes smooth. In FIG. 10, a space is provided between the fixed plate 202, the capacitor 81, and the radiator 92.

In FIG. 11, the fixing plate 203
Is in contact with the capacitor 81 and has a space between it and the radiator 92. Conversely, an interval may be provided between the capacitor 81 and the radiator 92. Then, as described above, the detour passage opening / closing means is normally in a closed state, and the vehicle speed wind and the cooling wind introduced by the cooling fan all flow into the radiator 92 after passing through the condenser 81. If the upper passage of the fixed plate is a main air passage A and the lower passage is a sub air passage B,
Since the division ratio of the condenser front surface area and the radiator front area with respect to the sub air passage B is small, the ventilation resistance of the sub air passage B with respect to the main air passage A when the cooling air flows is large, and the cooling air is the main air having a small ventilation resistance. There is a strong tendency to flow into passage A.

On the other hand, the outer circumferences of the radiator 92 and the capacitor 81 are connected to each other by a cut-off plate.
The strong tendency of the cooling air to flow into the main air passage A having a small ventilation resistance makes it difficult to expect the cooling performance obtained by the radiator performing heat exchange using the entire front surface area. Therefore, the cooling air inflow tendency was changed,
I want to ventilate the cooling air without unevenness in front of the radiator.

Therefore, an interval is provided between the fixed plate and the radiator or between the fixed plate and the capacitor. Due to the opened interval, the cooling air in the main air passage A also flows into the sub air passage B, so that the distribution of the cooling air flowing to the front of the radiator can be made uniform. Therefore, it is possible to make use of the cooling performance inherent in the radiator.

Embodiment 4 In this embodiment, as shown in FIG. 12, the fixed plate 2 is replaced with a rotatable one. That is, in the third embodiment, the fixed plate, the radiator 92, the capacitor 8
The effect of providing an interval between 1 has been described. Therefore, in this example, the fixing plate 2 is rotatably mounted on the radiator 92 side similarly to the damper 10 in consideration of the above-mentioned intention.

Thus, when the damper 10 serving as the bypass passage opening / closing means is opened, the leading end 25 (condenser 10 side) of the fixed plate 2 is also parallel, and the concentrated flow into the bypass passage 15 having low resistance is achieved. When the damper 10 is closed, the tip side 25 of the fixed plate 2 also rises to control the ratio of the area of the front surface of the condenser 81 and the radiator 92. Thereby, the heat radiation performance and the cooling performance are made efficient.

Comparative Example This example shows an example in which the fixing plate 2 was not provided in Example 1 for comparison. This is shown in FIG.
Shown in FIG. 3 shows the first embodiment except that the fixing plate 2 is not provided.
Is the same as FIG. As in the present comparative example, when the fixed plate 2 is not provided, when the damper 10 is first closed, the same operation and effect as in the first embodiment are produced. However, when the damper 10 is opened, although the low-temperature cooling air B is introduced below the radiator 92 from the bypass passage 15, the cooling air flows to the side with less resistance because there is no fixed plate, and the amount of air passing through the condenser is reduced. Extremely reduced.

Then, the amount of air passing through the condenser decreases.
This reduces the amount of heat radiation from the capacitor and
Cooling of the vehicle interior by increasing the refrigerant pressure inside the vehicle
Ability is reduced, accompanied by discomfort to occupants. Also, the refrigerant pressure
The increase in power, especially on the high pressure side (compressor discharge
The pressure increase on the outlet side only deteriorates the durability of cooler equipment
Instead of vehicles that lead to increased power consumption of the compressor
Fuel economy will deteriorate. Thus, the arrangement of the fixed plate
Not only improves the heat dissipation capacity of the radiator, but also
Significant significance, such as maintaining the heat radiation amount at an arbitrary capacity
It has.

[Brief description of the drawings]

FIG. 1 is a side view of a cooling device for an internal combustion engine according to a first embodiment.

FIG. 2 is an explanatory diagram of a flow of cooling air of a cooling device according to the first embodiment.

FIG. 3 is a perspective view of a blocking plate, a fixing plate, and a damper according to the first embodiment.

FIG. 4 is a control circuit diagram of the cooling device according to the first embodiment.

FIG. 5 is a flowchart of damper control according to the first embodiment.

FIG. 6 is a flowchart of another damper control according to the first embodiment.

FIG. 7 is a plan view of a cooling device for an internal combustion engine according to a second embodiment.

FIG. 8 is an enlarged view of a main part of FIG. 7;

FIG. 9 is an explanatory diagram of a fixing plate according to a third embodiment.

FIG. 10 is an explanatory diagram of another fixing plate according to the third embodiment.

FIG. 11 is an explanatory view of still another fixing plate according to the third embodiment.

FIG. 12 is a side view of a cooling device for an internal combustion engine according to a fourth embodiment.

FIG. 13 is a side view of a cooling device for an internal combustion engine in a comparative example.

FIG. 14 is a side view of a conventional cooling device for an internal combustion engine.

[Explanation of Codes] . . 10. damper, . . Actuator, 15. . . Detour path, 2. . . 2. fixing plate, . . Blocking plate, 81. . . Capacitor, 92. . . Radiator, 93. . . cooling fan,

Claims (1)

(57) [Claims] 1. A condenser for condensing a refrigerant of a cooling device, a radiator disposed rearward of the condenser in a vehicle traveling direction to cool cooling water of an internal combustion engine, and a cooling air flowing from the condenser side to the radiator side. Means for introducing, bypass path opening / closing means for opening / closing a bypass path to the radiator by bypassing the condenser, and when the bypass path is released, air between the condenser and the radiator passes through the condenser to the radiator. The main air passage flowing through
A fixed plate for bypassing the condenser into a sub-air passage flowing to the radiator; a blocking plate provided around the condenser and the radiator for blocking the flow of heated air from the internal combustion engine side; Control means for controlling the drive of the bypass passage opening / closing means in accordance with the state of the load.