JPH10122785A - Duplex heat-exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the thickness dimension of a duplex heat-exchanger while preventing the heat exchanging capability of the duplex heat-exchanger having different kinds of core parts from decreasing. SOLUTION: A combined area 24c between a condenser core plate 24a and a condenser tank main body 24b, of a condenser tank 24, is arranged so as to locate at a stage part 36d of a stepped part 36c which is formed at a combined area between a radiator core plate 36a and a radiator tank main body 36b, of a radiator tank 36. By doing so, an interference between both tanks 24, 36 can be prevented from occurring by a sinking portion (t) which is formed by the stepped part 36c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dual heat exchanger in which mutually different cores (heat exchange parts) are integrated, and more particularly to a radiator of an engine which is a driving source of a vehicle and an air conditioner for a vehicle. It is effective when applied to integration with a capacitor.

[0002]

2. Description of the Related Art Conventionally, an air conditioner for a vehicle has been mounted on a vehicle at a vehicle dealer or the like after the vehicle is completed. However, in recent years, an air conditioner for a vehicle has been standardly mounted on a vehicle. In the process, a vehicle air conditioner has been assembled together with a vehicle component.

Therefore, by integrating the radiator, which is a vehicle component, and the condenser, which is a vehicle air conditioner component, in order to reduce the size of both components and to reduce the number of assembling steps, different types of radiators and condensers are used. There have been proposed a large number of duplex heat exchangers in which the core portion is integrated. As a means for integrating the different types of cores, for example, in the invention described in Japanese Patent Application Laid-Open No. 3-17795, a means for integrating the cooling fins of the first core and the second core is proposed.

[0004]

By the way, the inventors of the present invention have attempted to reduce the size (hereinafter, referred to as the thickness dimension) of the duplex heat exchanger in the direction perpendicular to the longitudinal direction of the tube. After examining various means, including the means described in the above publication, the following was discovered.

[0005] That is, the largest thickness dimension of the first core portion is generally the first tank portion provided at the end of the first core portion. The first tank portion provided at the end of the second core portion has the largest thickness dimension of the first core portion. For this reason, when the thickness dimension of the duplex heat exchanger is reduced, both tank portions interfere with each other before both core portions interfere with each other.

Therefore, in reducing the thickness of the dual heat exchanger, it is necessary to reduce the size of a portion of the two tank portions that is parallel to the thickness (hereinafter, referred to as the tank thickness). is there. However, if the thickness of the tank is simply reduced in size, the pressure loss when the fluid flows in the tank increases, and the heat exchange capacity of the duplex heat exchanger is reduced.

SUMMARY OF THE INVENTION In view of the foregoing, it is an object of the present invention to reduce the thickness of a duplex heat exchanger while preventing the heat exchange capacity of the duplex heat exchanger from decreasing.

[0008]

The present invention uses the following technical means to achieve the above object. Claim 1
In the invention described in Item 5, the first tank portion (36) has the first
The first tank portion (2) is provided at a portion facing the tank portion (24).
A stepped portion (36c) which is depressed in the opposite direction to 4) is formed. Then, a first proximity portion (24c) of the first tank portion (24) which is closest to the second tank portion (36).
Are disposed at positions corresponding to the step portions (36d).

Thus, interference between the two tank portions (24, 36) can be prevented by the depression formed by the stepped portion (36c). Also, a stepped portion (36c)
The first tank part (24) and the second tank part (36)
Interference between the two tanks (24, 3
There is no need to greatly reduce the size of 6). Therefore, it is possible to prevent an increase in pressure loss in both tank portions (24, 36).

As described above, according to the present invention, it is possible to reduce the thickness of the duplex heat exchanger while preventing a decrease in the heat exchange capacity of the duplex heat exchanger. Claim 2
The first aspect is characterized in that the first proximity part (24c) is located closer to the second tank part (36) than the second proximity part. According to the third aspect of the present invention, the stepped portion (36
c) is characterized in that it is formed at a joint portion between the second tank core plate (36a) and the second tank body (36b).

Thus, it is not necessary to newly provide the second tank portion (36) with a "relief" for preventing interference with the first adjacent portion (24c) such as a concave portion. Therefore, it is possible to prevent an increase in the production cost of the second tank (36), and thus to prevent an increase in the production cost of the double heat exchanger. In the invention described in claim 4, the wall surface (24A) of the first tank core plate (24a) on the side of the first core portion (2) is located at a position corresponding to the stepped portion (36c). 2) It is characterized by being located on the side.

According to the fifth aspect of the present invention, the connecting portion (4
5) is characterized in that it is formed between both cooling fins (22, 32). In addition, the code | symbol in the parenthesis of each said means shows the correspondence with the concrete means of embodiment mentioned later.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; (First Embodiment) This embodiment is a dual heat exchanger for a vehicle using a condenser core for a vehicle air conditioner as a first core and a radiator core for an engine cooling as a second core.

Usually, the temperature of the refrigerant flowing through the condenser core portion is lower than the temperature of the engine cooling water flowing through the radiator core portion. Therefore, in this dual heat exchanger, the condenser core portion has an air flow upstream of the radiator core portion. And are arranged at the forefront of the engine room in series with the air flow. Hereinafter, the shape of the compound heat exchanger (hereinafter, abbreviated as heat exchanger) according to the present embodiment will be described.

FIG. 1 is a perspective view of a heat exchanger 1 according to the present embodiment, and FIG. 2 is a sectional view taken along line AA of FIG. Reference numeral 2 denotes a capacitor core, and reference numeral 3 denotes a radiator core.
The two core portions 2 and 3 are provided with a predetermined gap 46 between both tubes 21 and 32, which will be described later, in order to block heat conduction from each other.
And are arranged in series in the air flow. The condenser core 2 has a corrugated shape (FIG. 3) formed with a condenser tube 21 formed in a flat shape and serving as a refrigerant passage, and a plurality of bent portions 22a (see FIG. 3) brazed to the condenser tube 21. (Wave-shaped) cooling fins 22.

The radiator core 3 has the same structure as the capacitor core 2, and the condenser tube 2
A radiator tube 31 and a cooling fin 32 are disposed in parallel with the radiator tube 1. The tubes 21 and 31 and the cooling fins 22 and 23 are alternately stacked and brazed. The cooling fins 22, 32 are formed with louvers 22b, 32b for promoting heat exchange. The cooling fins 22, 32 are formed integrally with the louvers 22b, 32b by a roller forming method or the like. ing.

The two cooling fins 22, 32 are connected to the ends 22d, 32d of the two cooling fins 22, 32, which are opposite to each other in a direction perpendicular to the longitudinal direction of the tubes 21, 31. Are formed. As shown in FIG. 3, a plurality of (5 to 10 in this embodiment) bent portions are provided between one connecting portion 45 and the other connecting portion 45 among the plurality of connecting portions 45. 2
2a and 32a are formed.

FIG. 4 shows the two cooling fins 22 and 32 when they are unfolded.
Among them, the dimension E of the portion parallel to the longitudinal direction of both cooling fins 22 and 32 is not more than 5% of the dimension F between two adjacent joining portions 45 among the plurality of joining portions 45. The ratio of the dimension E to the dimension F (hereinafter, referred to as a coupling ratio E / F) will be described later in detail.

Since the bent portions 22a and 32a of the cooling fins 22 and 32 are in contact with the tubes 21 and 31, of the heat conducted between the cooling fins 22 and 32,
The heat conducted through the bent portions 22a and 32a is the largest.
Therefore, as shown in FIGS. 2 and 3, it is desirable that the connecting portion 45 is formed on the flat portions 22 c and 23 c of the cooling fins 22 and 32.

The width of both cooling fins 22 and 32 in the direction perpendicular to the longitudinal direction of both tubes 21 and 31 is larger than the flat width of both tubes 21 and 31 and, as shown in FIG. Both 22 and 32 project toward the gap 46 side. In addition, the gap 4 from the condenser tube 21
6 and the radiator tube 3
The details of the protrusion Lr protruding from 1 toward the gap 46 will be described later.

Reference numeral 48 denotes a side plate which forms a reinforcing member for the core portions 2 and 3.
Numerals 8 are arranged at both ends of both core portions 2 and 3 as shown in FIG. As shown in FIG. 2, the side plate 48 has a substantially U-shaped cross section and is integrally formed from a single aluminum plate. By the way, 49 is
It is a bracket for assembling the heat exchanger 1 to a vehicle.

As shown in FIG. 1, a first radiator tank 34 for distributing cooling water to each radiator tube 31 is provided at one end of the end of the radiator core 3 where the side plate 48 is not disposed. And a second radiator tank 36 for recovering the cooling water after the heat exchange is disposed on the other end side. At the upper end side of the first radiator tank 34, an inflow port 3 through which cooling water flowing out of the engine flows into the first radiator tank 34 is provided.
5 while a second radiator tank 36 is provided.
An outlet 37 through which cooling water flows out toward the engine is provided at a lower end side of the engine. In addition, 35a and 37a are:
External piping (not shown) is connected to both radiator tanks 34, 36
The joint pipes 35a, 37a are connected to the radiator tanks 34, 36 by brazing.

Reference numeral 24 denotes a first condenser tank 24 for distributing the refrigerant in the condenser core section 2 to each condenser tube 21, and reference numeral 25 denotes a second condenser tank section 2 for recovering the refrigerant after heat exchange (condensation). It is a condenser tank. Reference numeral 26 denotes an inlet for allowing the refrigerant discharged from the compressor (not shown) of the refrigeration cycle to flow into the first condenser tank 24, and reference numeral 27 designates the refrigerant having undergone heat exchange (condensation) to expand the refrigeration cycle. This is an outflow port for flowing out to a valve (not shown).

Reference numerals 26a and 27a denote joint pipes for connecting an external pipe (not shown) to the condenser tanks 24 and 25. These joint pipes 26a and 27a are connected to the respective condenser tanks by brazing. 2
4 and 25 are connected. By the way, FIG.
-B sectional view, showing the second radiator tank 36.
As shown in FIG. 5, a radiator core plate 36a made of aluminum is connected to the radiator tube 31.
And the second radiator core plate 36a
And a radiator tank main body 36b made of aluminum, which forms a space in the radiator tank 36.

The thickness T ₁ (dimension in the direction perpendicular to the longitudinal direction of the tubes 21, 31) of the radiator tank main body 36 b is equal to the radiator core plate 3.
6a is smaller than the thickness T ₂ of the. For this reason,
A step portion (recessed side) 36d which is depressed in a direction opposite to the first condenser tank 24 is provided at a connecting portion of the two 36a and 36b.
The stepped portion 36c having the
And at the opposite side.

On the other hand, similarly, the first condenser tank 24 is also made of an aluminum condenser core plate 24a connected to the condenser tube 21 and the first condenser tank 24 connected to the condenser core plate 24a.
And an aluminum condenser tank main body 24b which forms a space inside. The first condenser tank 24 is located at a position closest to the second radiator tank 36, that is, the condenser core plate 24.
a, the condenser tank main body portion 24b, and the connecting portion (first adjacent portion) 24c are positioned outward from the longitudinal direction of the tubes 21 and 31 so as to be located at a portion corresponding to the stepped portion 36d of the stepped portion 36c. It is located at a shifted position.

Incidentally, both core plates 24a and 36a and both tank body portions 24b and 36b are covered with a brazing material, and the coated brazing material is used to cover both core plates 24a and 36a and both tank body portions 24b and 36b.
Are brazed together. Since the first radiator tank 34 and the second condenser tank 25 have the same structure, the radiator tank 36 will be used hereinafter to mean both the radiator tanks 34 and 36 unless otherwise specified. The tank 24 is used to include both condenser tanks 24 and 25.

Next, the projecting dimensions Lc and Lr of the cooling fins 22 and 32 will be described. When the protrusion dimensions Lc and Lr increase, the heat radiation area of both cooling fins 22 and 32 increases, so that the heat radiation increases. However, both tubes 2
Since the temperature difference between the cooling fins 22 and 32 and the air becomes smaller from the end 1 and 31 toward the tips of the cooling fins 22 and 32, the amount of heat radiation does not increase as compared with the case where the protrusion dimensions Lc and Lr increase.

That is, when the protrusion Lc of the cooling fin 22 is 4 mm or more in the case of the condenser core 2, the rate of increase in the amount of heat radiation is saturated as shown in FIG. 32 with a protrusion Lr of 7
When the distance is equal to or larger than mm, as shown in FIG. On the other hand, when the protruding dimensions Lc and Lr increase, the ventilation resistance of the air passing through the core portions 2 and 3 increases substantially linearly with respect to the protruding dimensions Lc and Lr, as shown in FIG. .

The above study was conducted on a corrugated cooling fin with a louver, in which the louver pitch was 1 mm, the louver angle was 23 °, and the cooling fin height was 8 mm.
And a gap dimension L formed between the tubes 21 and 31
10 is a numerical analysis result by the finite element method when a constant wind speed (2 m / sec) is given from the capacitor core part 2 side when 10 mm is set to 10 mm.

Further, the inventors tried numerical analysis under various calculation conditions other than the above calculation conditions.
In the range of 4 to 10 mm, regardless of the thickness and the height of the cooling fin, the rate of increase of the heat radiation amount and the ventilation resistance are substantially functions of the protruding dimensions Lc and Lr as shown in FIGS. Was revealed. By the way, when the ventilation resistance increases and the amount of air passing through the cooling fins decreases, the amount of heat radiated from the core portions 2 and 3 per unit time decreases, so that the heat exchange efficiency decreases. Therefore, if the relationship between the protrusion dimensions Lc and Lr and the rate of increase in the amount of heat radiation is determined in consideration of the ventilation resistance, the results are as shown in FIGS.

That is, the rate of increase in the amount of heat radiation is maximum when the protrusion dimension Lc is about 4 mm in the capacitor core section 2 and is 5 to 6 m in the radiator core section 3.
m, and then gradually decrease thereafter. Next, the coupling ratio E / F between the cooling fins 22 and 32 will be described. When the coupling ratio E / F increases, the coupling portion 45 between the two cooling fins 22 and 32 increases, so that the amount of heat transferred from the radiator core portion 3 to the capacitor core portion 2 increases, and the heat exchange in the capacitor core portion 2 increases. Efficiency deteriorates.

Therefore, the inventors have proposed that the capacitor core 2
The relationship between the amount of deterioration of the heat exchange efficiency and the coupling ratio E / F was quantitatively investigated. As shown in FIG. 11, as the coupling ratio E / F became larger, the heat exchange in the capacitor core portion 2 became larger. It has been found that the amount of deterioration in efficiency increases almost linearly, and that the deterioration ratio of the capacitor can be suppressed to less than 2% when the coupling ratio E / F is 0.05 or less.

Note that the deterioration amount of the capacitor on the vertical axis in FIG. 11 indicates the heat exchange amount when there is no coupling portion 45 (when both core portions 2 and 3 are completely independent) and when the coupling portion 45 is provided. Is divided by the amount of heat exchange when there is no connecting portion 45. Next, features of the present embodiment will be described. The coupling portion 24c of the condenser tank 24 which is closest to the radiator tank 36 is the stepped portion 3c of the stepped portion 36c.
6D, the interference between the tanks 24 and 36 can be prevented by the amount of depression t formed by the stepped portion 36c.

Since the stepped portion 36c prevents interference between the condenser tank 24 and the radiator tank 36, it is not necessary to greatly reduce the size of both tanks 24 and 36. Therefore, it is possible to prevent an increase in pressure loss in both tanks 24, 36. As described above, according to the present embodiment, it is possible to reduce the thickness of the heat exchanger while preventing a decrease in the heat exchange capacity of the heat exchanger.

As is clear from the above description,
Since the condenser tank 24 and the radiator tank 36 can be made closer to each other by the depressed size t, in this embodiment, the coupling portion 24c is closest to the condenser tank 24 among the radiator tanks 36 as shown in FIG. It is located on the radiator tank 36 side from the vertex of the stepped portion 36c (the second proximity portion).

By the way, as described above, the binding site 24c
Is shifted outward in the longitudinal direction of both tubes 21 and 31 so as to be located at a position corresponding to the stepped portion 36d, so that the core area of the capacitor core portion 2 is shifted outward. h. However, as is clear from FIG. 5, since the portion corresponding to the increased core area faces the radiator tank 36, the airflow passing through the capacitor core portion 24 increases as the core area increases. Therefore, the heat exchange capacity cannot be increased to correspond to the increased core area.

Therefore, blindly, the binding site 24c
Is shifted outward, only the material cost of the condenser tube 21 and the cooling fins 22 increases, and the technical effect cannot be obtained. Therefore, the inventors have conducted various studies and found that the wall surface 24A of the capacitor core plate 24a facing the capacitor core portion 2 is positioned closer to the radiator core portion 3 than the position corresponding to the stepped portion 36c (h <H) was determined to be desirable.

Since the flow rate of the cooling water flowing through the radiator core 3 is sufficiently larger than the flow rate of the refrigerant flowing through the condenser core 3, the two condenser tanks 2 are usually used.
The capacity (size) of 4 and 25 is
4, 36, smaller than the capacity (size). According to the present embodiment, the smaller two condenser tanks 24, 2
Since 5 is shifted outward, the dimension in the direction of both tubes 21 and 31 when the heat exchanger is viewed as a whole does not change. Therefore, the thickness of the heat exchanger can be reduced while preventing the tubes 21 and 31 from increasing in size.

Further, since the stepped portion 36c is formed at the connecting portion between the radiator core plate 36a and the radiator tank main portion 36b, the radiator tank 36 is newly prevented from interfering with the connecting portion 24c such as a concave portion. There is no need to provide an "escape". Therefore, it is possible to prevent an increase in the production cost of the radiator tank 36, and thus to prevent an increase in the production cost of the heat exchanger.

Further, since heat is transferred from the radiator core section 3 to the capacitor core section 2 via the coupling section 45, the amount of heat transfer becomes smaller as the coupling ratio E / F becomes smaller as shown in FIG. can do. Further, as shown in FIG. 9, by increasing the protrusion dimension Lc of the cooling fins 22 of the capacitor core portion 2 by a predetermined amount, the rate of increase in the amount of heat radiation in the capacitor core portion 2 can be improved.

Therefore, the protrusion L of the cooling fin 22
By appropriately selecting c and the coupling ratio E / F, the amount of deterioration of the capacitor due to the provision of the coupling portion 45 can be offset by the amount of heat radiation due to the protrusion of the cooling fins 22. Since the cooling fins 22 protrude toward the gap 46 between the core portions 2 and 3, it is possible to prevent the external dimensions of the heat exchanger 1 from increasing.

Incidentally, in this embodiment, the protrusion dimension Lc is about 1.7 mm, and the coupling ratio E / F is about 0.05. That is, since the coupling ratio E / F is about 0.05, the deterioration amount of the capacitor is about 2%, but the protruding dimension Lc is about 1.7 m.
m, the heat radiation in the capacitor core 2 increases by about 2%. Therefore, the amount of deterioration of the condenser is offset by projecting the cooling fins 22.

The above dimensions are the same as those of the cooling fins 22, 32.
Must be appropriately selected depending on the thickness, shape and material composition of the louvers 22b, 32b, etc., and when the coupling ratio E / F is 0.05 or less, the protrusion dimension Lc is 1.7 to 7 m.
m is desirable. The dimension L _S of the gap 47 between the two cooling fins 22 and 32 may be a gap that can effectively block heat conduction, and specifically 0.5 mm
About 2 mm. Incidentally, in the present embodiment, about 0.
5 mm, the gap L between the tubes 21 and 31
Is about 4 mm.

The cooling fins 3 of the radiator core 3
1 also protrudes toward the capacitor core 2 side.
As indicated by 0, the amount of heat radiation in the radiator core 3 increases. Therefore, it is possible to suppress an increase in the outer dimensions of the heat exchanger 1 and increase the amount of heat radiation in the radiator core 3. Incidentally, in the present embodiment, the protrusion Lr of the cooling fin 32 is about 1.8 mm, and the amount of heat radiation can be increased by about 5%.

Further, by appropriately selecting the protrusion dimensions Lc and Lr, it is possible to easily adjust the heat radiation ability of the capacitor core 2 or the radiator core 3. Therefore, a desired design change can be made without making a significant design change of the heat exchanger. In addition, between one connecting portion 45 of the plurality of connecting portions 45 and the other connecting portion 45, a plurality of bending portions 22a and 32a of both cooling fins 22 and 32 (in the present embodiment,
(5 to 10) bent portions 22a and 32a are formed, so that the sum of the cross-sectional areas of the plurality of coupling portions 45, which is the cross-sectional area of the heat conduction path for conducting heat between the cooling fins 22 and 32, is provided. Can be reduced. Therefore, both cooling fins 2
Since the amount of heat conduction between 2, 32 can be reduced,
Heat conduction between the two cooling fins 22 and 32 can be effectively cut off.

Since the heat conduction between the cooling fins 22 and 32 is cut off by reducing the cross-sectional area of the heat conduction path, the cooling fins 22 and 32 are extended by lengthening the heat conduction path. As compared with the structure in which the heat conduction between the cooling fins 22 and 32 is prevented, the dimensional expansion between the two cooling fins 22 and 32 can be suppressed. Therefore, heat conduction between the two cooling fins 22 and 32 can be effectively cut off while suppressing an increase in the size of the heat exchanger 1.

Further, since both cooling fins 22 and 32 are integrally formed, the manufacturing cost of both cooling fins 22 and 32 can be reduced, and the manufacturing cost of heat exchanger 1 can be reduced. be able to. By the way, in recent years, in order to reduce the size of the engine room, each device in the engine room has been approached to a point where a maintenance contractor can perform maintenance. Similarly, the radiator core unit 3 is also arranged close to other devices. ing.

However, if the radiator core unit 3 is simply brought closer to other equipment, the air flow in the engine room is deteriorated (remains), so that the amount of air passing through the radiator core unit 3 is reduced and the radiator core unit 3 is reduced. The heat radiation capability of the core part 3 is reduced. Therefore, in order to secure a sufficient air flow to the radiator core unit 3, the radiator core unit 3 is
As shown in 2 and 13, they are mounted on the front side of the vehicle (engine room), and are arranged in such a manner that air flowing into the engine room from the front of the vehicle is effectively collected in the radiator core unit 3.

More specifically, devices other than the radiator core 3 disposed near the radiator core 3 and vehicle reinforcing members such as an upper reinforcing member (upper cross member) 100 and a lower reinforcing member (lower cross member) 101. Etc.,
By reducing the gap (distance) between the radiator core portion 3 and the radiator core portion 3, the configuration (layout) is such that air flowing into the engine room from the front of the vehicle does not flow directly to the air downstream side by bypassing the radiator core portion 3. .

Therefore, the air that has flowed into the engine room from the front of the vehicle flows toward the radiator core 3 as it approaches the radiator core 3 as shown in FIG. Therefore, when the condenser core 2 is disposed upstream of the radiator core 3 in the air, the air that has flowed into the engine room from the front of the vehicle bypasses the condenser core 2 and the condenser core 2 and the radiator core 3 The air flow passing through the radiator core portion 3 through the gap 46 is divided into a linear air flow passing through the core portions 2 and 3.

Then, in this state, the condenser tank 24
And the radiator tank 36 are close to each other, the gap 46 is substantially equal to the closed state, and the air flow flowing into the gap 46 by bypassing the capacitor core section 2 is interrupted. The lost air loses its place and starts flowing toward the capacitor core 2.

Therefore, as in the present embodiment, when the condenser tank 24 and the radiator tank 36 are brought close to each other, the amount of air passing through the condenser core 2 disposed upstream of the radiator core 3 in the air is reduced.
(Hereinafter, this phenomenon (effect) is referred to as a duct effect), and the heat exchange capacity of the condenser core portion 24 is improved.

In order to quantitatively investigate the duct effect, the inventors set the projecting dimensions Lc and Lr of both the cooling fins 22 and 32 to 0 mm, and set the two core parts 2 and 3
In a vehicle heat exchanger having an independent coupling ratio (E / F = 0), the relationship between the distance L between the tubes 21 and 31 and the rate of increase in the amount of air passing through the condenser core 2 was tested.

FIG. 15 is a graph showing the test results. The rate of increase of the air flow passing through the condenser core 2 is expressed as a percentage based on the average distance L between the tubes 21 and 31 = 20 mm. doing. Incidentally, in the above test, assuming that the vehicle heat exchanger according to the present embodiment is actually mounted on the vehicle, the radiator core 3 is connected to the air downstream side of the condenser core 2 as shown in FIG. And a cooling fan 51 disposed on the downstream side of the radiator core 3 in the air.

Here, the following conclusion can be obtained by considering the state of the distance L = 0 in the graph of FIG. That is, in a state where the distance L = 0, the two core portions 2 and 3 are in close contact with each other, so that no air flow bypassing the capacitor core portion 2 is generated. That is, from the viewpoint of the flow of air, the state where the distance L = 0 in the above test is a state where the gap 46 between the core portions 2 and 3 is closed, that is, a state where the condenser tank 24 and the radiator tank 36 are brought close to each other. Be similar.

Therefore, as shown in FIG.
From the test results and the above considerations that the air flow passing through the condenser core 2 increases as the distance becomes smaller, that is, as the distance L = 0, it is possible to obtain the duct effect by bringing the condenser tank 24 and the radiator tank 36 closer to each other. it can. Further, in the heat exchanger in which the condenser tank 24 and the radiator tank 36 are brought close to each other, the pressure loss when passing through the gap 46 between the two core portions 2 and 3 is as follows:
The pressure loss when passing through the gap 46 is negligible because it is sufficiently smaller than the pressure loss when passing through the core portions 2 and 3. That is, quantitatively, the state where the distance L = 0 in the above test is similar to the state where the condenser tank 24 and the radiator tank 36 are close to each other.

Therefore, in the heat exchanger in which the projecting dimensions Lc and Lr of both the cooling fins 22 and 32 are both 0 mm and the core portions 2 and 3 are independent, for example, the distance L = 2
When the distance is set to 0 mm, the rate of increase in the amount of air flow due to the duct effect is equal to the rate of increase in the amount of air when the distance L = 0 and the distance L = 2.
The difference from the increase rate of the air volume at 0 mm, that is, 20%.

FIG. 16 shows the relationship between the distance L and the rate of increase in heat exchange of the capacitor core portion 2 in the above test. FIG. 16 shows a state where the distance L = 0 as in FIG. This is similar to a state where the condenser tank 24 and the radiator tank 36 are brought close to each other. Therefore, the smaller the distance L, that is, the closer to the distance L = 0, the higher the heat exchange rate of the capacitor core portion 2.

It is conceivable that the heat transfer from the radiator core 3 to the capacitor core 2 via the side plate 48 may reduce the heat exchange efficiency of the capacitor core 2. However, the cross-sectional area of the side plate 48 that effectively contributes to the heat transfer is a small portion near the both header tanks 34 and 36 of the radiator core 3 and is smaller than the core area of the capacitor core 2. Because it is small enough, the decrease in heat exchange efficiency due to heat transfer can be almost ignored.

As described above, both cooling fins 2
Since the fins 2 and 32 are integrally formed with the louvers 22b and 32b by a roller molding method or the like, if the coupling ratio E / F is reduced, the formation of the coupling portion 45 becomes difficult, and the production cost of the cooling fins increases. I will. Therefore, it is desirable to make the coupling ratio E / F as large as possible from the viewpoint of manufacturing the cooling fin.

On the other hand, if the coupling ratio E / F is increased, the heat exchange of the capacitor core 2 is reduced as described above, so that it is not desirable to excessively increase the coupling ratio E / F. Therefore, for example, in the heat exchanger with the distance L = 20, the heat exchange of the capacitor core portion 2 can be improved by 10% (see FIG. 16) only by the duct effect, which corresponds to the deterioration amount of the capacitor of 10%. Value (coupling ratio E
/F=0.24), the coupling ratio E / F can be increased.

When the coupling ratio E / F is set to 0.1 or less, the deterioration of the capacitor is 5% (see FIG. 11).
Is considered, the protrusion dimension (deviation amount) Lc is -1.5 mm
(If the protruding dimension Lc is -1.5 mm, the heat radiation amount of the capacitor core portion 2 is reduced by 5% (see FIG. 9).) it can.

The protrusion dimension (deviation amount) Lc here
The cooling fins 22 of the condenser core portion 2 when the direction from the condenser tube 21 toward the radiator tube 31 is set to the positive direction with the end of the condenser tube 21 on the radiator tube 31 side as a reference position (0). Out of the radiator core 3 side. That is, when the protrusion dimension (deviation amount) Lc = −1.5 mm, the end of the cooling fin 22 is
2 shows a state in which it is located on the upstream side of the air from the end of.

Then, the inventors of the present invention compared the manufacturing costs (of the cooling fins) of the heat exchangers of various specifications and the heat exchange capacity of the condenser core portion 2 and found that the coupling ratio E /
F was concluded that 0.1 or less was appropriate. Further, considering the increase rate of the heat exchange due to the duct effect, as described above, the protrusion dimension (deviation amount) Lc is set to −1.5.
It may be up to 7 mm.

In the above-described embodiment, the present invention has been described with the first core part as the capacitor core part and the second core part as the radiator core part. However, the first core part as the radiator core part, The present invention can be implemented even when the portion is a capacitor core portion. Further, in the above-described embodiment, both tanks are constituted by the core plate and the tank body, but both tanks may be integrally formed by extrusion or the like.

In the above embodiment, the binding site 24
c is located closer to the radiator tank 36 than the vertex of the stepped portion 36c closest to the condenser tank 24 of the radiator tank 36, but the coupling portion 24c is positioned closer to the condenser tank 24 than the vertex of the stepped portion 36c. You may.

[Brief description of the drawings]

FIG. 1 is a perspective view of a compound heat exchanger according to an embodiment of the present invention.

FIG. 2 shows a heat exchanger core part (FIG. 1) according to an embodiment of the present invention.
(A-A section) of FIG.

FIG. 3 is a perspective view showing a shape of a cooling fin.

FIG. 4 is a development view of a cooling fin.

FIG. 5 is a BB cross section of FIG.

FIG. 6 is a graph showing the relationship between the rate of increase in the amount of heat dissipated by the cooling fins in the capacitor core and the projecting dimensions of the cooling fins.

FIG. 7 is a graph showing the relationship between the rate of increase in the amount of heat dissipated by the cooling fins in the radiator core and the protrusion dimensions of the cooling fins.

FIG. 8 is a graph showing a relationship between a rate of increase of a ventilation resistance of air passing through a cooling fin in a condenser core portion and a projection size of the cooling fin.

FIG. 9 is a graph showing the relationship between the rate of increase in the amount of heat dissipated by the cooling fins and the projected size of the cooling fins in consideration of ventilation resistance.

FIG. 10 is a graph showing the relationship between the rate of increase in the amount of heat radiation of the cooling fins and the projected size of the cooling fins in consideration of the ventilation resistance at the radiator core.

FIG. 11 is a graph showing a relationship between a deterioration amount of a capacitor and a coupling ratio.

FIG. 12 is a perspective view showing a state where the vehicle heat exchanger according to the present invention is mounted on a vehicle.

FIG. 13 is a top view showing a state where the vehicle heat exchanger according to the present invention is mounted on a vehicle.

FIG. 14 is a schematic diagram showing an air flow when the vehicle heat exchanger is mounted on a vehicle.

FIG. 15 is a graph investigating a relationship between a distance L between both tubes and an increasing rate of an air flow passing through a condenser core.

FIG. 16 is a graph showing the relationship between the distance L between both tubes and the rate of increase in heat exchange of the condenser core 2;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Heat exchanger, 2 ... Condenser core part, 3 ... Radiator core part, 4 ... Connection part, 21 ... Condenser tube, 22
... cooling fins, 23 ... side plates, 31 ... radiator tubes, 32 ... cooling fins, 33 ... side plates, 22a, 32a ... bent parts, 22b, 32b ... louvers, 45 ... coupling parts, 46 ... gaps, 24 ... 1 condenser tank (first tank portion), 24a: capacitor core plate (first core plate), 24b: capacitor tank body portion (first tank body portion), 24c: coupling portion (first proximity portion), 25 ... 2 condenser tank, 34 ... first radiator tank, 36 ... second radiator tank (second tank section), 36a ... radiator core plate (second
Core plate), 36b: Radiator tank main body (second tank main body), 36c: Stepped portion, 36d: Stepped portion.

Claims (5)

[Claims] 1. A first core (2) having a plurality of first tubes (21) through which a first medium flows, and disposed at both ends of the first tubes (21) to distribute the first medium. A first tank part (24) to be assembled, and a plurality of second tubes (31) arranged in parallel with the first tube (21) with a predetermined gap (46) and through which a second medium flows. ), A second tank portion (36) disposed at both ends of the second tube (31) for distributing and assembling a second medium, and the two core portions (2, 3). A connecting part (4) for connecting a part of (3)
5), the first tank portion (2) of the second tank portion (36).
4), and is formed at a portion facing the first tank portion (2).
4) a stepped portion (36c) having a stepped portion (36d) depressed in the opposite direction, and the second tank portion (3) of the first tank portion (24).
(6) a double heat exchanger, wherein a first proximity portion (24c) closest to the step (36) is disposed at a position corresponding to the step portion (36d). 2. The second tank section (3), wherein the first proximity section (24c) is closer to the second tank section (36) than the second proximity section closest to the first tank section (24).
The double heat exchanger according to claim 1, wherein the heat exchanger is located on the side of (6). 3. The second tank part (36) includes a second tank core plate (36a) coupled to the second tube (31), and a second tank core plate (3).
6a) and a second tank body (36b) coupled to the second tank core plate (36a) and the second tank body (36b). The double heat exchanger according to claim 1, wherein the heat exchanger is formed at a site. 4. The first tank part (24) includes a first tank core plate (24a) connected to the first tube (21), and a first tank core plate (24a) connected to the first tank core plate (24a).
And a first tank core plate (24a).
The wall surface (24A) on the core part (2) side is provided with the stepped part (3
The double heat exchanger according to any one of claims 1 to 3, wherein the double heat exchanger is located closer to the first core portion (2) than a position corresponding to 6c). 5. Between each of the tubes (21, 31),
A first cooling fin (22) and a second cooling fin (32) for promoting heat exchange are provided, respectively, and the coupling part (45) is provided with the two cooling fins (22, 3).
The double heat exchanger according to any one of claims 1 to 4, wherein the double heat exchanger is formed between 2).