HEAT EXCHANGER

Description

TECHNICAL FIELD

The present invention relates to a heat exchanger.

BACKGROUND ART

JP2016-118335A discloses a heat exchanger in which core portions are provided so as to be layered with each other. The core portions have top and bottom header tanks and heat exchange pipes through which heat transfer medium flows between the top and bottom header tanks.

Partition portions are provided in the header tanks, and by the heat exchange pipes, lower passes for allowing the heat transfer medium to flow from the top header tank towards the bottom header tank and upper passes for allowing the heat transfer medium to flow from the bottom header tank towards the top header tank are formed in the core portions.

SUMMARY OF INVENTION

However, with this heat exchanger, the lower passes for allowing the heat transfer medium to flow downwards and the upper passes for allowing the heat transfer medium to flow upwards are provided in an alternate manner. Therefore, when the heat exchange is to be performed by condensing the heat transfer medium in the heat exchange pipes of the core portions, the heat transfer medium having an increased density needs to be pushed up several times in the heat exchange pipes, and so, the flow of the heat transfer medium is deteriorated in efficiency.

An object of the present invention is to provide a heat exchanger capable of facilitating flow of a heat transfer medium.

According to an aspect of the present invention, a heat exchanger configured to heat air by condensing a heat transfer medium undergoing a phase change between a liquid phase and a gaseous phase, the heat exchanger includes a plurality of core portions provided such that the plurality of core portions are overlapped with each other in a flow direction of the air and such that the heat transfer medium flows continuously, the core portions each comprising: an upper header tank to which the heat transfer medium is supplied; a lower header tank arranged below the upper header tank; and a plurality of tubes configured to connect the upper header tank and the lower header tank, the plurality of tubes being configured to perform heat exchange between the heat transfer medium flowing inside the tubes and the air flowing around the tubes, and a communication passage configured to allow communication between the lower header tank of a first core portion of the core portions and the upper header tank of a second core portion of the core portions and to allow the heat transfer medium to flow from the lower header tank to the upper header tank, the second core portion being arranged so as to be overlapped with the first core portion in the flow direction of the air.

In the heat exchanger of the above aspect, a heat transfer medium that has been supplied to a first core portion flows from an upper header tank of the core portion towards the lower header tank side through tubes. The heat transfer medium in the lower header tank of the first core portion is supplied to a second core portion through a communication passage. The heat transfer medium that has been supplied to the second core portion flows from the upper header tank of the core portion towards the lower header tank through the tubes.

Therefore, it is possible to allow the heat transfer medium, whose density has been increased by being condensed as the heat transfer medium flows towards the downstream side, to flow from the upper side to the lower side in the tubes of both core portions that communicate with each other via the communication passage. With such a configuration, there is no need to cause the heat transfer medium, whose density has been increased by being condensed, to flow upward from the lower side to the upper side in the tubes of the core portions. Therefore, according to the present invention, the heat exchanger capable of facilitating the flow of the heat transfer medium.

BRIEF DESCRIPTION OF DRAWINGS

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

FIG. 2 is an exploded perspective view showing a structure of a communication passage.

FIG. 3 is a sectional view taken along a ling III-III in FIG. 2.

FIG. 4 is a front view showing a first block.

FIG. 5 is a front view showing a second block.

FIG. 6 is a front view showing a third block.

FIG. 7 is a front view showing a fourth block.

FIG. 8 is a front view showing a fifth block.

FIG. 9 is a front view showing a sixth block.

FIG. 10 is a graph showing passage resistances of the communication passages that are formed by using respective blocks.

FIG. 11 is a perspective view of a main part showing a first modification.

FIG. 12 is a perspective view of a main part showing a second modification.

FIG. 13 is a perspective view of a third modification.

FIG. 14 is an enlarged view of an adapter in the third modification.

DESCRIPTION OF EMBODIMENTS

In the following, a heat exchanger 10 according to embodiments of the present invention will be described with reference to the drawings.

An overall configuration of the heat exchanger 10 will be described first with reference to FIG. 1. FIG. 1 is a perspective view of the heat exchanger 10 according to the embodiment of the present invention.

The heat exchanger 10 is installed in a vehicle (not shown). The heat exchanger 10 performs a heat exchange between air that is used for air-conditioning and a heat transfer medium that is circulated in an air-conditioning device (not shown) and that undergoes a phase change between a liquid phase and a gaseous phase.

Specifically, the heat exchanger 10 is provided in an HVAC (a Heating Ventilation and Air Conditioning) unit (not shown) through which the air used for the air-conditioning passes. The heat exchanger 10 is a condenser that, when the air-conditioning device performs a cabin-heating operation, performs the heat exchange with the air used for the air-conditioning to heat the air by condensing the heat transfer medium.

The heat exchanger 10 has: an upstream-side core portion 16 serving as a first core portion to which the heat transfer medium is supplied; a downstream-side core portion 14 serving as a second core portion to which the heat transfer medium from the upstream-side core portion 16 is supplied; and reinforcing members 18 that are respectively provided on both side portions of the heat exchanger 10.

The downstream-side core portion 14 and the upstream-side core portion 16 are arranged so as to be overlapped with each other in the air-flow direction 12. The downstream-side core portion 14 is arranged on the windward side. The upstream-side core portion 16 is arranged on the downwind side.

In this embodiment, although a case in which the heat exchanger 10 is configured of two core portions, the downstream-side core portion 14 and the upstream-side core portion 16, will be described, this embodiment is not limited thereto. The heat exchanger 10 may be configured of three or more core portions. In addition, the upstream-side core portion 16 and the downstream-side core portion 14 represent a first core portion and a second core portion, respectively, among a set of core portions that are arranged along the flow direction of the heat transfer medium in a consecutive manner.

The downstream-side core portion 14 and the upstream-side core portion 16 respectively have upper header tanks 20A, 20B to which the heat transfer medium is supplied and lower header tanks 22A, 22B that are arranged below the upper header tanks 20A, 20B. The downstream-side core portion 14 has a plurality of fins (not shown) and a plurality of tubes 24 that connect the upper header tank 20A and the lower header tank 22A and that perform the heat exchange between the heat transfer medium that flows inside the tubes 24 and the air that flows around the tubes 24. In addition, the upstream-side core portion 16 has a plurality of fins (not shown) and a plurality of tubes 24 that connect the upper header tank 20B and the lower header tank 22B and that perform the heat exchange between the heat transfer medium that flows inside the tubes 24 and the air that flows around the tubes 24.

Each header tank 20A, 20B, 22A, 22B, the tubes 24, and the fins are made of a metal such as aluminum and are integrally joined to each other by brazing, etc.

In addition, the heat exchanger 10 has a communication passage 26 that allows communication between the lower header tank 22B of the upstream-side core portion 16 and the upper header tank 20A of the downstream-side core portion 14.

(Tubes)

The tubes 24 provided on each of the core portions 14 and 16 respectively connect the header tanks 20A, 20B, 22A, 22B of the respective core portions 14 and 16 with each other and perform the heat exchange between the heat transfer medium that flows inside the tubes 24 and the air that flows around the tubes 24.

The respective core portions 14 and 16 are provided so as to intersect with the air-flow direction 12 such that the air can flow between the respective tubes 24. The respective core portions 14 and 16 are provided so as to be overlapped with each other in the air-flow direction 12 such that the air can flow through in a consecutive manner.

The plurality of tubes 24 are arranged side by side in parallel, thereby being layered with interval gaps. The tubes 24 are each formed to have a flat shape and are layered in the thickness direction. The fins are provided between adjacent tubes 24. The tubes 24 are layered in the direction that intersects with the air-flow direction 12. Each of the tubes 24 is formed with an inner flow passage through which the heat transfer medium flows.

(Fins)

The fins are provided between the adjacent tubes 24, and are layered alternately with the tubes 24. The fins are formed to have a wave-like shape along the longitudinal direction of the tubes 24 and are joined to two adjacent tubes 24. The air supplied by a blower (not shown) of the air-conditioning device flows around the plurality of tubes 24 and the fins. Therefore, the heat transfer medium that flows inside the tubes 24 can undergo the heat exchange with the air via surfaces of the tubes 24 and the fins. As described above, the fins promote the heat exchange between the heat transfer medium and the air.

(Reinforcing Members)

The reinforcing members 18 are respectively provided on both side portions of the downstream-side core portion 14 and the upstream-side core portion 16. The reinforcing members 18 are in contact with the fins that are provided on both side portions of the downstream-side core portion 14 and the upstream-side core portion 16. End portions of the reinforcing members 18 in the longitudinal direction are respectively engaged with the header tanks 20A, 20B, 22A, 22B, thereby linking and reinforcing between pairs of header tanks 20A, 20B, 22A, 22B. When the tubes 24 and the fins are brazed to form the downstream-side core portion 14 and the upstream-side core portion 16, the reinforcing members 18 are integrated with the downstream-side core portion 14 and the upstream-side core portion 16 by being brazed to the fins.

(Header Tank)

The header tanks 20A, 20B, 22A, and 22B each has a tubular shape elongated in the arrangement direction of the tubes 24. The header tanks 20A, 20B, 22A, and 22B each has a closed cross-sectional shape. In a state in which the heat exchanger 10 is attached, an upper surface of each of the upper header tanks 20A and 20B is formed to have a curved shape in which the center portion in the width direction is projected upwards. The respective end portions of the respective header tanks 20A, 20B, 22A, and 22B have substantially the same shape.

The upper header tanks 20A and 20B and the lower header tanks 22A and 22B of the respective core portions 14 and 16 are arranged so as to face each other. The respective end portions of the plurality of tubes 24 in the longitudinal direction are inserted into and joined to the upper header tanks 20A and 20B and the lower header tanks 22A and 22B that are arranged so as to face each other. Each of the header tanks 20A, 20B, 22A, 22B temporarily stores the heat transfer medium.

A first end of the upper header tank 20B of the upstream-side core portion 16 forms a heat transfer medium inlet 30, through which the heat transfer medium enters. A supply pipe 31 that supplies the heat transfer medium is connected to the heat transfer medium inlet 30. In other words, the upstream-side core portion 16 has the heat transfer medium inlet 30, through which the heat transfer medium enters, on a first-side end portion on a first-side-portion side 32.

A second end of the upper header tank 20B of the upstream-side core portion 16 is closed. The heat transfer medium that has entered the upper header tank 20B of the upstream-side core portion 16 flows to the lower header tank 22B through the respective tubes 24. The heat transfer medium performs the heat exchange with the air while flowing through the tubes 24.

A first end of the lower header tank 22B of the upstream-side core portion 16 is closed. A second end of the lower header tank 22B of the upstream-side core portion 16 forms a heat transfer medium outlet 34 through which the heat transfer medium flows out. The above-described communication passage 26 is connected to the heat transfer medium outlet 34.

A second end of the upper header tank 20A of the downstream-side core portion 14 forms a heat transfer medium inlet 28 through which the heat transfer medium enters. The above-described communication passage 26 is connected to the heat transfer medium inlet 28.

With such a configuration, the communication passage 26 allows the communication between the upstream-side core portion 16 and the downstream-side core portion 14 at a second-side end portion of the upstream-side core portion 16 on a second-side-portion side 36. Specifically, the communication passage 26 allows the heat transfer medium that flows out from a second end portion of the lower header tank 22B of the upstream-side core portion 16 to flow to a second end portion of the upper header tank 20A of the downstream-side core portion 14.

A first end of the upper header tank 20A of the downstream-side core portion 14 is closed. The heat transfer medium that has entered the upper header tank 20A of the downstream-side core portion 14 flows to the lower header tank 22A through the respective tubes 24. The heat transfer medium performs the heat exchange with the air while flowing through the tubes 24.

A second end of the lower header tank 22A of the downstream-side core portion 14 is closed. A first end of the lower header tank 22A of the downstream-side core portion 14 forms a heat transfer medium outlet 40 through which the heat transfer medium flows out. A recovery pipe 42 that recovers the heat transfer medium is connected to the heat transfer medium outlet 40.

(Communication Passage)

FIG. 2 is an exploded perspective view showing the structure of the communication passage 26.

As shown in FIGS. 1 and 2, the communication passage 26 is formed of a lower connector 50, an upper connector 52, and a tube member 54 that allows the communication between the lower connector 50 and the upper connector 52. The inner cross-sectional area of the tube member 54 is sufficiently larger than the inner cross-sectional area of the tubes 24.

The lower connector 50 is connected to the lower header tank 22B of the upstream-side core portion 16 so as to be communicable. The upper connector 52 is connected to the upper header tank 20A of the downstream-side core portion 14 so as to be communicable.

The one end of the tube member 54 is connected to a connection hole 56 that is formed in the lower connector 50 and the other end of the tube member 54 is connected to a connection hole (not shown) that is formed in the upper connector 52. The tube member 54 allows the communication between the lower connector 50 and the upper connector 52.

In a state in which the lower connector 50 is connected to the corresponding lower header tank 22B and the upper connector 52 is connected to the corresponding upper header tank 20A, the connection hole 56 of the lower connector 50 and the connection hole (not shown) of the upper connector 52, to which the tube member 54 is connected, face each other. In addition, the connection hole 56 of the lower connector 50 and the connection hole (not shown) of the upper connector 52 open in the same direction as the extending direction of the tubes 24 (see FIG. 1) extending in the vertical direction.

(Block)

FIG. 3 is a sectional view taken along a line III-III in FIG. 2.

As shown in FIGS. 2 and 3, the lower connector 50 and the upper connector 52 are each formed of a block 60 formed as the same member.

The block 60 forming each of the lower connector 50 and the upper connector 52 has a flat surface 62 that is arranged so as to face each of the core portions 14 and 16. In addition, the block 60 has a ridge-like projected portion 64 that projects to the opposite side of the surface 62. With such a configuration, the block 60 is formed to have a triangular prism shape.

The surface 62 of the block 60 has a first insertion hole 66 and a second insertion hole 68 into which the respective end portions of the upper header tanks 20A and 20B, which are arranged so as to be overlapped with each other, or the respective end portions of the lower header tanks 22A and 22B, which are arranged so as to be overlapped with each other, can be respectively inserted. The first insertion hole 66 and the second insertion hole 68 have substantially the same shape as the respective end portions of the respective header tanks 20A, 20B, 22A, and 22B. In addition, the first insertion hole 66 and the second insertion hole 68 are arranged at the same interval as the arrangement interval of the respective header tanks 20A, 20B, 22A, 22B, which are arranged so as to be overlapped with each other.

An innermost portion of the second insertion hole 68 is closed by a closing surface 70. With such a configuration, the second insertion hole 68 forms a closing portion 72 that closes the end portion of the header tank to be inserted.

The block 60 has the above-described connection hole 56, which communicates with the first insertion hole 66, in an end surface 74 (see FIG. 2) serving as an intersecting surface that extends in the direction orthogonal to the extending direction of the surface 62. The first insertion hole 66 has, on the innermost side thereof, an innermost surface 76 that is in parallel with the surface 62. An inner passage 78 that communicates with the connection hole 56 is opened in the innermost surface 76.

The connection hole 56 is opened perpendicularly to the end surface 74 (see FIG. 2) and extends parallel to the surface 62. The connection hole 56 is positioned at the midpoint between the center line C1 that extends through the center of the first insertion hole 66 and the center line C2 that extends through the center of the second insertion hole 68 (see FIG. 3). In other words, the first insertion hole 66 and the second insertion hole 68 are arranged at the positions symmetrical with respect to the connection hole 56.

With such a configuration, by arranging the end surface 74, in which the connection hole 56 is opened, so as to face upwards, it is possible to utilize the block 60 as the lower connector 50. In addition, by arranging the end surface 74, in which the connection hole 56 is opened, so as to face downwards, it is possible to utilize the block 60 as the upper connector 52.

As shown in FIG. 1, the end portion of the lower header tank 22B of the upstream-side core portion 16 is inserted into the first insertion hole 66 of the block 60 forming the lower connector 50, and thereby, the lower header tank 22B is made to communicate with the connection hole 56. In addition, the end portion of the lower header tank 22A of the downstream-side core portion 14 is inserted into the second insertion hole 68, and thereby, the end portion of the lower header tank 22A is closed.

Next, the end portion of the upper header tank 20B of the upstream-side core portion 16 is inserted into the second insertion hole 68 of the block 60 forming the upper connector 52, and thereby, the end portion of the upper header tank 20B is closed. In addition, the end portion of the upper header tank 20A of the downstream-side core portion 14 is inserted into the first insertion hole 66, and thereby, the upper header tank 20A is made to communicate with the connection hole 56.

The connection hole 56 is arranged at the midpoint between the center line C1 that extends through the center of the first insertion hole 66 and the center line C2 that extends through the center of the second insertion hole 68 (see FIG. 3). Therefore, the connection hole 56 of the lower connector 50 that is formed of the block 60, which is arranged such that the end surface 74 faces upwards, and the connection hole 56 of the upper connector 52 that is formed of the block 60, which is arranged such that the end surface 74 faces downwards, face each other.

In addition, the connection hole 56 is opened perpendicularly to the end surface 74 and extends parallel to the surface 62. Therefore, the opening direction of the connection hole 56 of the lower connector 50 and the opening direction of the connection hole 56 of the upper connector 52 coincide with the extending direction of the tubes 24 extending in the vertical direction.

(Inner Passage)

As shown in FIG. 3, the inner passage 78 that allows the communication between the first insertion hole 66 and the connection hole 56 extends linearly in the direction at an oblique angle of 40 degrees with respect to the innermost surface 76 of the first insertion hole 66. The inner passage 78 is formed, for example, by machining using a drill.

In this embodiment, a plurality of blocks 60 having differently shaped inner passage 78 are prepared (blocks 60-1, 60-2, 60-3, 60-4, 60-5, and 60-6). Then, the passage resistance was measured in the communication passage 26 by using each of the blocks 60.

(First Block)

FIG. 4 is a front view showing the first block 60-1.

As shown in FIG. 4, the inner passage 78 of the first block 60-1 is formed of a machined hole 80 that is formed so as to extend lineally in the oblique direction from the innermost surface 76 of the first insertion hole 66 towards the connection hole 56. The machined hole 80 is formed parallel to the end surface 74 of the first block 60-1.

(Second Block)

FIG. 5 is a front view showing the second block 60-2.

As shown in FIG. 5, the inner passage 78 of the second block 60-2 is formed of a machined hole 82 that is formed so as to extend lineally in the oblique direction from the innermost surface 76 of the first insertion hole 66 towards the connection hole 56. The machined hole 82 is inclined in the direction approaching the end surface 74 of the second block 60-2 as the machined hole 82 extends from the innermost surface 76 towards the connection hole 56. The angle α1 formed between a parallel line 84 parallel to the end surface 74 and the center line C3 of the machined hole 82 is 25.4 degrees.

With such a configuration, compared with a case in which the connection hole 56 and the machined hole 82 are orthogonal to each other, it is possible to make the flow of the heat transfer medium smoother.

(Third Block)

FIG. 6 is a front view showing the third block 60-3.

As shown in FIG. 6, the inner passage 78 of the third block 60-3 is formed of a first machined hole 86 and a second machined hole 88 that are formed so as to extend lineally in the oblique direction from the innermost surface 76 of the first insertion hole 66 towards the connection hole 56.

The first machined hole 86 and the second machined hole 88 are formed so as to partially overlap with each other and form a single inner passage 78. The opening area of the inner passage 78 of the third block 60-3 that opens to the innermost surface 76 is larger than the opening area of the inner passage 78 of the first block 60-1.

The first machined hole 86 and the second machined hole 88 are formed parallel to the end surface 74 of the third block 60-3.

(Fourth Block)

FIG. 7 is a front view showing the fourth block 60-4.

As shown in FIG. 7, the inner passage 78 of the fourth block 60-4 is formed of a first machined hole 90, a second machined hole 92, and a third machined hole 94 that are formed so as to extend lineally in the oblique direction from the innermost surface 76 of the first insertion hole 66 towards the connection hole 56.

The first machined hole 90, the second machined hole 92, and the third machined hole 94 are formed so as to partially overlap with each other and form a single inner passage 78. The opening area of the inner passage 78 of the fourth block 60-4 that opens to the innermost surface 76 is larger than the opening area of the inner passage 78 of the third block 60-3.

The first machined hole 90, the second machined hole 92, and the third machined hole 94 are formed parallel to the end surface 74 of the fourth block 60-4.

(Fifth Block)

FIG. 8 is a front view showing the fifth block 60-5.

As shown in FIG. 8, the inner passage 78 of the fifth block 60-5 is formed of a first machined hole 96 and a second machined hole 98 that are formed so as to extend lineally in the oblique direction from the innermost surface 76 of the first insertion hole 66 towards the connection hole 56. The first machined hole 96 is formed parallel to the end surface 74. The second machined hole 98 is inclined in the direction approaching the end surface 74 of the fifth block 60-5 as the second machined hole 98 extends from the innermost surface 76 towards the connection hole 56. The angle α2 formed between the parallel line 84 parallel to the end surface 74 and the center line C4 of the second machined hole 98 is 25.4 degrees.

The first machined hole 96 and the second machined hole 98 are formed so as to partially overlap with each other and form a single inner passage 78. The opening area of the inner passage 78 of the fifth block 60-5 that opens to the innermost surface 76 is larger than the opening area of the inner passage 78 of the first block 60-1 and the opening area of the inner passage 78 of the second block 60-2.

(Sixth Block)

FIG. 9 is a front view showing the sixth block 60-6.

As shown in FIG. 9, the inner passage 78 of the sixth block 60-6 is formed of a first machined hole 100 and a second machined hole 102 that are formed so as to extend lineally in the oblique direction from the innermost surface 76 of the first insertion hole 66 towards the connection hole 56.

The first machined hole 100 is formed parallel to the end surface 74. The second machined hole 102 is inclined in the direction approaching the end surface 74 of the sixth block 60-6 as the second machined hole 102 extends from the innermost surface 76 towards the connection hole 56. The angle α3 formed between the parallel line 84 parallel to the end surface 74 and the center line C5 of the second machined hole 102 is 37 degrees.

The first machined hole 100 and the second machined hole 102 are formed so as to partially overlap with each other and form a single inner passage 78. The opening area of the inner passage 78 of the sixth block 60-6 that opens to the innermost surface 76 is larger than the opening area of the inner passage 78 of the first block 60-1 and the opening area of the inner passage 78 of the second block 60-2.

In the above, each of the machined holes 80, 82, 86, 88, 90, 92, 94, 96, 98, 100, and 102 that forms the inner passage 78 of each of the blocks 60-1, 60-2, 60-3, 60-4, 60-5, and 60-6 is formed by a drill having the same diameter. In addition, the components of each of the blocks 60-1, 60-2, 60-3, 60-4, 60-5, and 60-6 other than the inner passage 78 are the same.

Next, the passage resistance will be described.

FIG. 10 is a graph showing the passage resistance in the communication passage 26 that is formed by using each of the blocks 60-1, 60-2, 60-3, 60-4, 60-5, and 60-6. The bar shape indicating the passage resistance of each communication passage 26 is labeled with the reference numerals of each block used.

In this graph, numerically converted passage resistance is shown by the length of the bar shape. In graph, the vertical axis indicates the passage resistance, with lower passage resistance indicating a better result.

From this graph, the passage resistance of the communication passage 26, which is formed of the sixth block 60-6, is the lowest, and it is clear that the configuration employing the sixth block 60-6 is superior to the configurations employing other blocks 60-1, 60-2, 60-3, 60-4, and 60-5. Therefore, the sixth block 60-6 is employed for each of the connectors 50 and 52 of this embodiment.

In this embodiment, although a case in which each of the connectors 50 and 52 is formed with the sixth block 60-6 will be described, this embodiment is not limited thereto. Each of the connectors 50 and 52 may be formed by using any of the blocks 60-1, 60-2, 60-3, 60-4, 60-5, 60-6 described above.

(Tube Member)

As shown in FIG. 2, the tube member 54 is formed of a cylindrical member extending linearly. Ridges 110 extending in the circumferential direction are respectively formed on a first end portion and a second end portion of the tube member 54.

Ring-shaped brazing materials 112, which are each a brazing material shaped into a ring shape, are attached to an outer circumferential portions of the tube member 54. The ring-shaped brazing materials 112 are melted upon heating and braze the tube member 54 to each of the connectors 50 and 52.

(Action and Effects)

According to the embodiments mentioned above, the advantages described below are afforded.

The heat exchanger 10 is the heat exchanger 10 that heats the air by condensing the heat transfer medium that undergoes the phase change between the liquid phase and the gaseous phase.

The heat exchanger 10 includes the upstream-side core portion 16 and the downstream-side core portion 14 serving as the plurality of core portions that are provided such that the upstream-side core portion 16 and the downstream-side core portion 14 are overlapped with each other in the air-flow direction 12 and such that the the heat transfer medium flows continuously, the upstream-side core portion 16 and the downstream-side core portion 14 respectively having: the upper header tank 20A, 20B to which the heat transfer medium is supplied; the lower header tank 22A, 22B arranged below the upper header tank 20A, 20B; and the plurality of tubes 24 configured to connect the upper header tank 20A, 20B and the lower header tank 22A, 22B, the plurality of tubes 24 being configured to perform the heat exchange between the heat transfer medium flowing inside the tubes and the air flowing around the tubes. The heat exchanger 10 includes the communication passage 26 configured to allow the communication between the lower header tank 22B of the upstream-side core portion 16 serving as the first core portion and the upper header tank 20A of the downstream-side core portion 14 serving as the second core portion and to allow the heat transfer medium to flow from the lower header tank 22B to the upper header tank 20A, the downstream-side core portion 14 being arranged so as to be overlapped with the upstream-side core portion 16 in the air-flow direction 12.

According to the heat exchanger 10 having such a configuration, the heat transfer medium that has been supplied to the upstream-side core portion 16 serving as the first core portion flows from the upper header tank 20B of the upstream-side core portion 16 to the lower header tank 22B through the tubes 24. The heat transfer medium in the lower header tank 22B of the upstream-side core portion 16 is supplied to the downstream-side core portion 14 serving as the second core portion through the communication passage 26.

The heat transfer medium that has been supplied to the downstream-side core portion 14 then flows from the upper header tank 20A of the downstream-side core portion to the lower header tank 22A through the tubes 24. With such a configuration, the heat transfer medium flowing through each of the core portions 14 and 16 flows from the upper side to the lower side while increasing the density by being condensed in each of the core portions 14 and 16.

Therefore, it is possible to allow the heat transfer medium, whose density is increased by being condensed as the heat transfer medium flows towards the downstream side, to flow from the upper side to the lower side through the tubes 24 of both of the core portions 14 and 16, which are communicated by the communication passage 26. With such a configuration, there is no need to cause the heat transfer medium, whose density has been increased by being condensed, to flow upward from the lower side to the upper side in the tubes 24 of the respective core portions 14 and 16. Therefore, it is possible to provide the heat exchanger 10 capable of facilitating the flow of the heat transfer medium.

In addition, the upper header tank 20B of the upstream-side core portion 16 serving as the first core portion has the heat transfer medium inlet 30, through which the heat transfer medium enters, on the first end portion, and the lower header tank 22A of the downstream-side core portion 14 serving as the second core portion has the heat transfer medium outlet 40, through which the heat transfer medium flows out, on the first end portion. The communication passage 26 allows the communication between the second end portion of the lower header tank 22B of the upstream-side core portion 16 serving as the first core portion and the second end portion of the upper header tank 20A of the downstream-side core portion 14 serving as the second core portion.

According to such a configuration, the heat transfer medium enters the upstream-side core portion 16 from the first end portion of the upper header tank 20B, and the heat transfer medium flows out from the second end portion of the lower header tank 22B through the communication passage 26.

Therefore, in the upstream-side core portion 16, as the heat transfer medium flows from the first-side end portion, through which the heat transfer enters, towards the second-side end portion, through which the heat transfer medium flows out, the temperature of the flowing heat transfer medium is decreased, and so, in the upstream-side core portion 16, the temperature is decreased from the first-side end portion towards the second-side end portion.

In addition, in the downstream-side core portion 14, the heat transfer medium enters from the second end portion of the upper header tank 20A via the communication passage 26, and the heat transfer medium flows out from the second end portion of the lower header tank 22A.

Therefore, in the downstream-side core portion 14, the temperature of the flowing heat transfer medium is decreased as the heat transfer medium flows from the second-side end portion, through which the heat transfer medium enters, towards the first-side end portion, through which the heat transfer medium flows out, and so, in the downstream-side core portion 14, the temperature is decreased from the second-side end portion towards the first-side end portion.

The first-side end portion of the upstream-side core portion 16 having a higher temperature is arranged so as to be overlapped with the first-side end portion of the downstream-side core portion 14 having a lower temperature. In addition, the second-side end portion of the upstream-side core portion 16 having a lower temperature is arranged so as to be overlapped with the second-side end portion of the downstream-side core portion 14 having a higher temperature.

Therefore, with the heat exchanger 10, in which the upstream-side core portion 16 and the downstream-side core portion 14 are arranged so as to be overlapped with each other, a temperature difference is suppressed between the first-side end portion and the second-side end portion, and so, a more uniform temperature distribution can be achieved for the heat exchanger 10.

In addition, the communication passage 26 is formed of: the lower connector 50 connected to the lower header tank 22B of the upstream-side core portion 16 serving as the first core portion so as to be communicable; the upper connector 52 connected to the upper header tank 20A of the downstream-side core portion 14 serving as the second core portion so as to be communicable; and the tube member 54 connected to the connection holes 56 of the lower connector 50 and the upper connector 52 so as to allow the communication between the lower connector 50 and the upper connector 52.

According to such a configuration, by changing the length of the tube member 54, it is possible to change a separation distance between the lower connector 50 and the upper connector 52.

Therefore, even in a case in which the length of the tubes 24 of the respective core portions 14 and 16 is changed due to the specification change, it is possible to accommodate the specification change by simply adjusting the length of the tube member 54 that connects the lower connector 50 and the upper connector 52.

In a state in which the lower connector 50 is connected to the corresponding lower header tanks 22A, 22B and the upper connector 52 is connected to the corresponding upper header tanks 20A, 20B, the connection hole 56 of the lower connector 50 and the connection hole 56 of the upper connector 52, to which the tube member 54 is to be connected, face with each other and open in the direction same as the extending direction of the tubes 24.

According to such a configuration, compared with a case in which the lower connector 50 is communicated with the upper connector 52 by arranging the tube member 54 between both of the connectors 50 and 52 at an oblique angle, it becomes possible to accommodate the change in the length of the tubes 24 without changing the angle for the connection holes 56.

The lower connector 50 and the upper connector 52 are formed of the same member.

According to such a configuration, compared with a case in which the lower connector 50 and the upper connector 52 are formed of different members, it is possible to suppress manufacturing cost.

The member forming each of the lower connector 50 and the upper connector 52 is formed of the block 60, the block 60 having, in the surface 62, the first insertion hole 66 and the second insertion hole 68 into which the each end portion of the upper header tanks 20A, 20B, which are arranged so as to be overlapped, or the each end portion of the lower header tanks 22A, 22B, which are arranged so as to be overlapped, can be inserted, and the block 60 having the connection hole 56 in communication with the first insertion hole 66 in the end surface 74, serving as the intersecting: surface, extending in the direction intersecting with the extending direction of the surface 62, the connection hole 56 being arranged at the midpoint between the center line C1 extending through the center of the first insertion hole 66 and the center line C2 extending through the center of the second insertion hole 68.

According to such a configuration, by arranging the block 60 such that the connection hole 56 opens downward, it is possible to utilize the block 60 as the upper connector 52. In addition, by arranging the block 60 such that the connection hole 56 opens upward, it is possible to utilize the block 60 as the lower connector 50.

Therefore, by simply changing the orientation of the block 60, it is possible to utilize the block 60 as the upper connector 52 and the lower connector 50.

The second insertion hole 68 of the block 60 is not connected to the connection hole 56, and the closing portion 72 that is blocked by the closing surface 70 is formed.

Therefore, it is possible to close the end portion of the header tank that is inserted into the second insertion hole 68 of the block 60 with the closing portion 72. Therefore, compared with a case in which a closing member for closing the end portion of each of the header tanks 20B, 22A needs to be prepared separately, it is possible to reduce the cost and to eliminate the time and effort for attaching the closing member.

(First Modification)

FIG. 11 is a perspective view of a main part showing a first modification.

In a heat exchanger 200 according to the first modification, a lower adapter 202 is connected to the end portion of the lower header tank 22B of the upstream-side core portion 16 and the end portion of the the lower header tank (not shown) of downstream-side core portion 14.

The lower adapter 202 is formed of a block body that is made of aluminum formed in a rectangular parallelepiped shape. The lower adapter 202 has a closing portion (not shown) that closes the end portion of the lower header tank 22B of the upstream-side core portion 16.

The lower adapter 202 is connected to the end portion of the lower header tank (not shown) of the downstream-side core portion 14 and has a cylindrical portion 204 that is in communication with the lower header tank (not shown). The cylindrical portion 204 forms a heat transfer medium discharge passage 206 that discharges the heat transfer medium from the lower header tank (not shown) of the downstream-side core portion 14. The recovery pipe (not shown) for recovering the heat transfer medium is connected to the cylindrical portion 204.

The cylindrical portion 204 extends in the direction orthogonal to the extending direction of the lower header tank (not shown) of the downstream-side core portion 14. With such a configuration, it is possible to draw out the recovery pipe (not shown) to be connected to the cylindrical portion 204 in the direction orthogonal to the extending direction of the lower header tank (not shown).

In this modification, compared with a case in which the recovery pipe, which is connected to the lower header tank (not shown) of the downstream-side core portion 14, is drawn in the direction orthogonal to the extending direction of the lower header tank by bending the recovery pipe, it is possible to reduce a space required on the first-side-portion side 32 of the heat exchanger 200.

(Second Modification)

FIG. 12 is a perspective view of a main part showing a second modification.

In a heat exchanger 300 according to the second modification, an upper adapter 302 is further connected to the end portion of the upper header tank 20B of the upstream-side core portion 16 and the end portion of the upper header tank 20A of the downstream-side core portion 14.

The upper adapter 302 is formed of a block body that is made of aluminum formed in a rectangular parallelepiped shape. The upper adapter 302 has the closing portion (not shown) that closes the end portion of the upper header tank 20A of the downstream-side core portion 14.

The upper adapter 302 is connected to the end portion of the upper header tank 20B of the upstream-side core portion 16 (not shown) and has a cylindrical portion 304 that is in communication with the upper header tank 20B. The cylindrical portion 304 forms a heat transfer medium supply passage 306 that supplies the heat transfer medium to the upper header tank 20B of the upstream-side core portion 16. A supply pipe (not shown) for supplying the heat transfer medium is connected to the cylindrical portion 304.

The cylindrical portion 304 extends in the direction orthogonal to the extending direction of the upper header tank 20B of the upstream-side core portion 16. With such a configuration, it is possible to draw out the supply pipe to be connected to the cylindrical portion 304 in the direction orthogonal to the extending direction of the upper header tank 20B.

In this modification, compared with a case in which the supply pipe, which is connected to the upper header tank 20B of the upstream-side core portion 16, is drawn in the direction orthogonal to the extending direction of the upper header tank 20B by bending the supply pipe, it is possible to reduce a space required on the first-side-portion side 32 of the heat exchanger 300.

(Third Modification)

FIG. 13 is a perspective view of a third modification. FIG. 14 is an enlarged view of an adapter 412 of the third modification.

As shown in FIG. 13, a heat exchanger 400 according to the third modification has, on the first-side-portion side 32 of the downstream-side core portion 14 serving as the second core portion, a heat transfer medium discharge passage 402 that is in communication with the lower header tank 22A (not shown) and that extends towards the upper header tank 20A side.

(Heat Transfer Medium Discharge Passage)

The heat transfer medium discharge passage 402 is formed of a discharge connector 410, the adapter 412, and a tube member 414 that allows the communication between the discharge connector 410 and the adapter 412.

(Discharge Connector)

The discharge connector 410 is formed of the block 60 described above, and by arranging the block 60 such that the end surface 74 of the block 60, in which the connection hole 56 is opened, faces upward, the block 60 is utilized as the discharge connector 410.

The end portion of the lower header tank 22B of the upstream-side core portion 16 is inserted into the second insertion hole 68 of the discharge connector 410, and the end portion of the lower header tank 22B is closed by the closing surface 70 of the second insertion hole 68. The end portion of the lower header tank (not shown) of the downstream-side core portion 14 is inserted into the first insertion hole 66 of the discharge connector 410, and the lower header tank (not shown) is in communication with the connection hole 56 of the discharge connector 410.

(Adapter)

As shown in FIG. 14, the adapter 412 is formed of a block body that is made of aluminum formed in a rectangular parallelepiped shape.

The adapter 412 has a first cylindrical portion 420 to which the end portion of the upper header tank 20B of the upstream-side core portion 16 is connected to and that is in communication with the upper header tank 20B. The adapter 412 has a second cylindrical portion 422 that is provided on the side of the first cylindrical portion 420.

The adapter 412 has a closing hole (not shown) to which the end portion of the upper header tank 20A of the downstream-side core portion 14 is connected and that closes the end portion of the upper header tank 20A.

The adapter 412 has a connection hole 424 that is opened towards the discharge connector 410 side, and the connection hole 424 faces the connection hole 56 of the discharge connector 410. The connection hole 424 is in communication with the second cylindrical portion 422.

(Tube Member)

A first end portion of a tube member 414 is connected to the connection hole 56 of the discharge connector 410. A second end portion of the tube member 414 is connected to the connection hole 424 of the adapter 412.

The supply pipe (not shown) for supplying the heat transfer medium is connected to the first cylindrical portion 420 of the adapter 412. The recovery pipe (not shown) for recovering the heat transfer medium is connected to the second cylindrical portion 422 of the adapter 412.

With such a configuration, the heat transfer medium supplied from the supply pipe is supplied to the upper header tank 20B of the upstream-side core portion 16 via the adapter 412. In addition, the heat transfer medium discharged from the lower header tank (not shown) of the downstream-side core portion 14 is recovered by the recovery pipe, which is connected to the first cylindrical portion 420 of the adapter 412, via the discharge connector 410 and the tube member 414.

The heat exchanger 400 according to this modification has, on the first-side-portion side 32 of the upstream-side core portion 16 serving as the second core portion, the heat transfer medium discharge passage 402 that is in communication with the lower header tank 22A and that extends towards the upper header tank 20A side.

According to the heat exchanger 400 having such a configuration, it is possible to gather the drawing out positions for the supply pipe and the recovery pipe at the upper part of the first-side end portion of the heat exchanger 400. Therefore, compared with a case in which the supply pipe and the recovery pipe are drawn from different positions, the pipe installation operation becomes easier.

Although the embodiment of the present invention has been described in the above, the above-mentioned embodiment merely illustrates a part of application examples of the present invention, and the technical scope of the present invention is not intended to be limited to the specific configurations of the above-described embodiment.

The present application claims a priority based on Japanese Patent Application No. 2022-118920 filed with the Japan Patent Office on Jul. 26, 2022, the entire content of which are incorporated into this specification by reference.