JP2019138490A - Heat exchanger - Google Patents

Abstract

To provide a heat exchanger comprising a connection header with high brazing quality.SOLUTION: A heat exchanger comprises: a first header member 211 having a plurality of heat transfer pipes 20a through which a heat medium flows, a plurality of insertion holes through which the heat transfer pipes 20a are inserted, and a planar first connection part; and a second header member 212 having a planar second connection part, and connected to the first header member 211 to form a flow passage for the heat medium. Also, at least one of the first header member 211 and the second header member 212 has overhang parts 211a and 212a communicating the plurality of heat transfer pipes 20a, and the first connection part and the second connection part are connected.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a heat exchanger.

  A plurality of heat transfer tubes arranged in multiple stages in the tube row direction are arranged in parallel in the tube row direction and the tube row direction orthogonal to the longitudinal direction of the heat transfer tube, and end portions in the longitudinal direction of the heat transfer tubes adjacent in the tube row direction are connected to each other. Heat exchangers having connected headers that communicate with each other have been developed.

  For example, in the heat exchanger of Patent Document 1, heat exchange units configured by alternately arranging flat heat transfer tubes and corrugated fins in the vertical direction of the heat exchanger are arranged in two rows in parallel, and in the tube row direction. The ends of adjacent flat heat transfer tubes communicate with each other through a connection header having a partition in the vertical direction. Further, the connection header is configured by a first plate member having an insertion port for a flat heat transfer tube and a corrugated second plate member in which semi-cylindrical shapes are continuously arranged.

JP2015-113983A

  In the heat exchanger described in Patent Document 1, it is necessary to close the contact surfaces of the first plate member and the second plate member constituting the connection header by brazing to form a heat medium flow path. The brazing quality is affected by the distance between the members to be brazed, and if the distance between the members is large, the brazing becomes insufficient and there is a possibility that the brazing will be poor. Therefore, in order to improve the brazing quality, it is necessary to increase the dimensional accuracy of the members to be joined or to apply a load to the members to be joined to reduce the distance between the members to be joined.

  In the heat exchanger described in Patent Document 1, in addition to the opposing contact surfaces of the first plate member and the second plate member, it is also necessary to braze two surfaces perpendicular to this. For this reason, it is difficult to reduce the distance between the members of all the joining portions, and the brazing quality may be deteriorated.

  This invention is made | formed in view of the above-mentioned situation, and it aims at providing the heat exchanger provided with the connection header with high brazing quality.

  In order to achieve the above object, a heat exchanger according to the present invention includes a plurality of heat transfer tubes through which a heat medium flows, a plurality of insertion holes through which the heat transfer tubes are inserted, and a planar first joint portion. 1 header member and a 2nd header member which has a planar 2nd joined part, and is joined to the 1st header member and constitutes a channel of a heat carrier. In addition, at least one of the first header member and the second header member has an overhang portion that allows the plurality of heat transfer tubes to communicate with each other, and the first joint portion and the second joint portion are joined.

  According to the present invention, the first header member and the second header member constituting the flow path of the heat medium are joined by the planar first joint and the planar second joint, so that the connection It is possible to improve the brazing quality of the header.

The front side perspective view of the outdoor unit which concerns on Embodiment 1 of this invention Rear side perspective view of outdoor unit according to Embodiment 1 Sectional plan view of the outdoor unit cut along line A-A 'in FIG. The perspective view of the heat exchanger which concerns on Embodiment 1. FIG. Conceptual diagram of heat exchange unit according to Embodiment 1 The enlarged view of the connection header which concerns on Embodiment 1 Sectional side view of the connection header cut | disconnected by the B-B 'line | wire of FIG. Sectional top view of the connection header cut | disconnected by the C-C 'line | wire of FIG. Sectional side view of the connection header before assembly according to Embodiment 1 Sectional drawing of the brazing sheet which concerns on Embodiment 1. FIG. Sectional side view of the connection header after brazing according to Embodiment 1 Graph showing the relationship between clearance distance and pressure loss Sectional side view of the connection header which concerns on Embodiment 2 of this invention Sectional top view of the connection header which concerns on Embodiment 2. FIG. Sectional side view of the connection header before assembly according to Embodiment 2 Schematic of plate thickness when pressed into semi-cylindrical shape Sectional side view of the connection header after brazing according to Embodiment 2 Cross-sectional side view of connection header after brazing when brazing sheet having brazing material on both sides is used Cross-sectional side view of a connection header having a half-angle tubular shape overhang Cross-sectional side view of a connecting header having an overhang using a lid member

  Hereinafter, a heat exchanger according to an embodiment of the present invention will be described with reference to the drawings.

(Embodiment 1)
The heat exchanger 20 according to the present embodiment is accommodated in the outdoor unit 1 of the air conditioner and heats between air flowing outside the heat exchanger 20 and a heat medium flowing inside the heat exchanger 20. Exchange. As shown in FIGS. 1 and 2, the outdoor unit 1 includes a housing 10. As shown in FIG. 3, the housing 10 houses a heat exchanger 20, a fan 60 that causes air to flow through the heat exchanger 20, a motor 61 that drives the fan 60, and a compressor (not shown).

  As shown in FIGS. 1 and 2, the casing 10 has a rectangular parallelepiped shape. The exhaust port 11 exhausts air, the fan guard 13 covers the exhaust port 11, the intake ports 12a and 12b, and the intake port 12b. A rear guard 14 is provided.

  The exhaust port 11 is an opening formed in the front panel 10 a of the housing 10, and air exchanged by the heat exchanger 20 is exhausted by the fan 60. The exhaust port 11 is covered with a mesh-shaped fan guard 13. This prevents the user from touching the rotating fan 60 and ensures the safety of the user.

  The air inlet 12 a is an opening formed in the side panel 10 b of the housing 10, and allows air to flow into the heat exchanger 20 in the housing 10 by the rotation of the fan 60.

  The air inlet 12 b is an opening formed in the back panel 10 c of the housing 10, and allows air to flow into the heat exchanger 20 in the housing 10 by the rotation of the fan 60. The air inlet 12b is covered with a mesh-like rear guard 14. This prevents the user from touching the heat exchanger 20 inside the housing 10 and ensures the safety of the user.

  As shown in the cross-sectional view of FIG. 3, the inside of the housing 10 is divided into two regions of a machine chamber 100a and a fan chamber 100b by a separator plate 10f. The machine room 100a is an area that contains a compressor, a receiver, a valve, an electric circuit that controls the valve, and the like (not shown) and is shielded from the outside air. The fan chamber 100 b is a region that houses the heat exchanger 20, the fan 60, the motor 61, the fan frame 62 that supports the fan 60, and the like and is exposed to the outside air through the intake ports 12 a and 12 b and the exhaust port 11.

  The fan 60 is disposed at the center of the fan chamber 100b. The motor 61 is connected to the fan 60 and rotationally drives the fan 60. The fan 60 and the motor 61 are attached to a fan frame 62 fixed to the housing 10.

  The fan 60 is rotationally driven by a motor 61 and allows air to flow into the housing 10 from the air inlets 12a and 12b, and flows into the housing 10 from the air inlets 12a and 12b and passes the air that has passed through the heat exchanger 20 to the air outlet 11. To the outside of the housing 10.

  As shown in FIG. 3, the heat exchanger 20 is disposed in the housing 10 in an L shape in plan view along the air inlets 12 a and 12 b. The end of the heat exchanger 20 on the machine room 100a side is connected to the compressor through a refrigerant pipe 20d disposed in the machine room 100a.

  As shown in FIG. 4, the heat exchanger 20 includes a heat exchange unit 200a, 200b that holds a plurality of heat transfer tubes 20a through which a heat medium is circulated, and a heat transfer tube 20a of the heat exchange unit 200a and a heat transfer unit 200b. A connection header 21 that allows the heat medium to flow through the heat pipe 20a and a refrigerant pipe 20d that connects the heat transfer pipe 20a and the compressor are provided.

  As schematically shown in FIG. 5, the heat transfer tube 20a has a flat cross-sectional shape. Thereby, the heat exchange efficiency of the heat exchanger 20 can be improved. The material of the heat transfer tube 20a is an aluminum alloy. The heat exchange units 200a and 200b include a plurality of heat transfer tubes 20a that are stacked with the flat portions facing each other.

  The heat transfer tube 20a is connected to a rectangular plate-shaped heat radiation fin 20b. Specifically, the heat radiating fin 20b has a plurality of through holes in the tube step direction in which the heat transfer tubes 20a are stacked. And the heat exchanger tube 20a is inserted and connected to each through-hole. Further, the heat transfer tube 20a is connected to a plurality of heat radiation fins 20b, and the heat transfer tubes 20a and the heat radiation fins 20b have a lattice shape as a whole as shown in FIG.

  The heat exchange units 200a and 200b are provided with the same number of heat transfer tubes 20a. The heat exchange unit 200a and the heat exchange unit 200b are arranged in parallel in the tube row direction and the tube row direction orthogonal to the longitudinal direction of the heat transfer tube 20a. One end of the heat transfer tube 20a is connected to the refrigerant tube 20d. Moreover, the other end part of the heat exchanger tube 20a is connected to the connection header 21, as shown in FIG.

  As shown in FIGS. 7 and 8, the connection header 21 includes a first header member 211 and a second header member 212. The first header member 211 is a flat plate-like member, and includes a semi-cylindrical protruding portion 211a. The overhang portion 211a is formed at a position corresponding to the heat transfer tube 20a. Moreover, the overhang | projection part 211a is provided with the insertion hole 211b which penetrates each heat exchanger tube 20a of the heat exchange units 200a and 200b, as shown to the exploded view of FIG. Further, the periphery of the overhanging portion 211a is a planar first joining portion 211c.

  The second header member 212 is a flat plate-like member and includes a semi-cylindrical protruding portion 212a. A plurality of overhanging portions 212 a are formed at positions facing the overhanging portion 211 a of the first header member 211. Further, the periphery of the overhang portion 212a is a planar second joint portion 212c.

  As shown in FIGS. 7 and 8, the heat transfer tube 20a is inserted into the insertion hole 211b of the first header member 211, and the first header member 211 and the heat transfer tube 20a are joined by brazing.

  Further, the first header member 211 and the second header member 212 are arranged at positions where the overhanging portion 211a and the overhanging portion 212a face each other, and the planar first joining portion 211c and the planar second joining portion 212c. Then, they are joined by brazing. Thereby, a cylindrical flow path with both ends closed is formed by a pair of opposed projecting portions.

  Then, the assembly method of the outdoor unit 1 provided with the heat exchanger 20 is demonstrated.

  First, the first header member 211 and the second header member 212 are manufactured by press working. As shown in FIG. 10, the material of the first header member 211 and the second header member 212 is a brazing in which a brazing layer that is a brazing material 22a, a base material 22b, and an anticorrosion layer that is an anticorrosion material 22c are laminated. This is a sheet 22. For example, the brazing material 22a is an Al—Si alloy, the base material 22b is an A3003 aluminum alloy to which Mn is added, and the anticorrosion material 22c is an Al—Zn alloy.

  When the first header member 211 and the second header member 212 are pressed, the direction of the material is determined when the first header member 211 and the second header member 212 are joined to form the connection header 21. The brazing materials 22a located on the joint surfaces are in contact with each other, and the anticorrosion material 22c is on the outside, that is, the side from which the overhang portions 211a and 212a protrude. Thereby, while ensuring the brazing property of the 1st junction part 211c and the 2nd junction part 212c, the connection header 21 excellent in corrosion resistance can be obtained with the anticorrosion material 22c.

  Subsequently, the heat exchange units 200a and 200b are manufactured. The radiating fins 20b manufactured by press working are aligned at a predetermined pitch. The brazing sheet 22 similar to that of the first header member 211 and the second header member 212 is used as the material of the radiation fin 20b. Further, the heat transfer tubes 20a made of aluminum alloy manufactured by extrusion are aligned at a predetermined pitch. Then, the heat transfer tubes 20a are press-fitted into the insertion holes of the aligned heat radiation fins 20b.

  Further, the refrigerant pipe 20d is made of the brazing sheet 22. The refrigerant pipe 20d is connected to the heat transfer pipe 20a inserted through the insertion hole formed in the refrigerant pipe 20d by brazing. The brazing sheet 22 constitutes the refrigerant pipe 20d in such a direction that the brazing material 22a is inside the refrigerant pipe 20d and the anticorrosion material 22c is outside the refrigerant pipe 20d. Thereby, the brazing property of the heat transfer tube 20a and the refrigerant tube 20d and the corrosion resistance of the refrigerant tube 20d are ensured.

  The heat exchange units 200a and 200b manufactured as described above are arranged in parallel in the tube row direction, and one end of the heat transfer tube 20a is inserted into the insertion hole of the refrigerant tube 20d. Further, the other end of the heat transfer tube 20a is inserted into the insertion hole 211b of the first header member 211 formed by press working. And the 1st header member 211 and the 2nd header member 212 are temporarily fixed in the position where the overhang part 211a and the overhang part 212a oppose. The first header member 211 and the second header member 212 are temporarily fixed by caulking. Temporary fixing may be performed using a jig, and it is preferable to press-contact the first joint portion 211c of the first header member 211 and the second joint portion 212c of the second header member 212. Further, after temporarily fixing the second header member 212 to the first header member 211, the heat transfer tube 20 a may be inserted into the insertion hole 211 b of the first header member 211.

  Subsequently, the assembled heat exchanger 20 is put into a brazing bath heated to about 580 to 620 ° C. in a nitrogen gas atmosphere. As a result, the brazing material 22a of the brazing sheet 22 is melted, and the contacting members are brazed together. As a result, the space formed between the overhanging portion 211a of the first header member 211 and the overhanging portion 212a of the second header member 212 is closed to form a flow path for the heat medium. Therefore, the heat transfer tube 20a of the heat exchange unit 200a inserted through the first header member 211 communicates with the heat transfer tube 20a of the heat exchange unit 200b adjacent thereto, and the heat medium can be circulated.

  Then, the brazed heat exchanger 20 is bent into an L shape as shown in FIG. 4 and accommodated in the housing 10 together with the compressor, the fan 60, the motor 61, etc., and the outdoor unit 1 is assembled.

  As schematically shown in the cross-sectional view of FIG. 11, the brazing material 22 a heated and melted in the brazing tank is subjected to surface tension between the first header member 211 and the second header member 212, and Aggregates between the heat transfer tube 20a and the first header member 211. Also, the molten brazing material 22a of the first header member 211 passes through the gap between the heat transfer tube 20a and the first header member 211 by a capillary phenomenon, and is on the outside of the first header member 211, that is, on the anticorrosive material 22c side. Also aggregate and form fillets. As a result, the first header member 211 and the second header member 212 are joined, and the pressure resistance of the joined portion against the pressure of the heat medium, that is, the internal pressure of the connection header 21 can be secured.

  Here, when the insertion amount M of the heat transfer tube 20a with respect to the first header member 211 is insufficient, the brazing material 22a adheres to the end of the heat transfer tube 20a. Thereby, the flow path of the heat medium formed in the heat transfer tube 20a is blocked, and the heat medium may not flow. Therefore, the insertion amount M of the heat transfer tube 20a is determined based on the brazing material distance R which is the height of the aggregated brazing material 22a, the position variation of the end of the heat transfer tube 20a after the heat transfer tube 20a is inserted into the connection header 21, and the first It is necessary to determine the shape of the header member 211 in consideration of the shape variation at the time of pressing.

  On the other hand, when the insertion amount M is increased, the gap distance N between the end of the heat transfer tube 20a and the inner wall of the second header member 212 is decreased. FIG. 12 shows the relationship between the pressure loss Δp that occurs when the heat medium flows from the end of the heat transfer tube 20a of the heat exchange unit 200a to the end of the heat transfer tube 20a of the heat exchange unit 200b using the gap distance N as a parameter. Show. It can be seen that the pressure loss Δp is reduced by increasing the gap distance N, and approaches saturation when the gap distance N is set to be equal to or greater than the flat portion thickness T of the heat transfer tube 20a. Therefore, it is preferable that the clearance distance N> the flat portion thickness T of the heat transfer tube 20a. Further, the distance L between the inner walls, which is the distance between the inner wall of the overhanging portion 211a and the inner wall of the overhanging portion 212a, is an insertion amount M in which the end portion of the heat transfer tube 20a is not blocked by the brazing with the flat thickness T of the heat transfer tube 20a. It is preferable to set the value to be equal to or greater than

  As described above, the heat exchanger 20 according to the present embodiment joins the planar first joint portion 211 c of the first header member 211 and the second joint portion 212 c of the second header member 212. Thus, the flow path of the heat medium is configured. For this reason, the brazing quality of the connection header 21 can be improved. Further, since the planar first joint portion 211c surrounding the overhang portions 211a and 212a and the planar second joint portion 212c are joined by brazing, a closed heat medium flow path can be easily formed. Can do.

  In the present embodiment, the overhanging portion 211a is formed on the first header member 211 and the overhanging portion 212a is formed on the second header member 212 to form a heat medium flow path. Not limited. For example, the overhang portions 211a and 212a may be formed on only one of the first header member 211 and the second header member 212 to form a heat medium flow path.

  Moreover, in this Embodiment, although the material of the 1st header member 211 and the 2nd header member 212 decided to be the brazing sheet 22 which laminated | stacked three types of materials, it is not restricted to this. For example, you may use the brazing sheet which laminated | stacked two types of materials, the brazing material 22a and the base material 22b. In this case, the thickness of the base material 22b is preferably set to a thickness that can satisfy the pressure resistance performance even when corrosion progresses.

(Embodiment 2)
Then, the heat exchanger 20 which concerns on Embodiment 2 of this invention is demonstrated. In the first embodiment, the overhang portions 211a and 212a are formed smoothly by press working. However, in order to suppress the strength reduction due to press working, the overhang portions 211a and 212a are thickened. It is desirable. Hereinafter, an example of a method for increasing the thickness of the overhang portions 211a and 212a will be described.

  As shown in FIG. 13, the heat exchanger 20 according to the present embodiment is different from the first embodiment in that the overhang portions 211 d and 212 d have a continuous step shape. Since other configurations are the same as those of the first embodiment, the same reference numerals are given.

  As shown in FIGS. 13 and 14, the connection header 21 includes a first header member 211 and a second header member 212. The first header member 211 is a flat plate-like member and includes a semi-cylindrical protruding portion 211d. Specifically, the inner surface and the outer surface of the overhang portion 211d are formed in a continuous step shape by press working. The overhang portion 211d is formed at a position corresponding to each heat transfer tube 20a of the heat exchange units 200a and 200b. Moreover, the overhang | projection part 211d is provided with the insertion hole 211e in the position corresponding to each heat exchanger tube 20a, as shown to the exploded view of FIG. The periphery of the overhang portion 211d is a planar first joint portion 211f.

  The second header member 212 is a flat plate-like member and includes a semi-cylindrical protruding portion 212d. Specifically, the inner surface and the outer surface of the overhang portion 212d are formed in a continuous step shape by press work, like the overhang portion 211d of the first header member 211. The overhang portion 212d is formed at a position facing the overhang portion 211d. Further, the periphery of the overhang portion 212d is a planar second joint portion 212f.

  As shown in FIG. 10, the material of the first header member 211 and the second header member 212 is a brazing in which a brazing layer that is a brazing material 22a, a base material 22b, and an anticorrosion layer that is an anticorrosion material 22c are laminated. This is a sheet 22. Specifically, as in Embodiment 1, the brazing material 22a is an Al—Si alloy, the base material 22b is an aluminum alloy, and the anticorrosion material 22c is an Al—Zn alloy.

  When the first header member 211 and the second header member 212 are pressed, the direction of the material is determined when the first header member 211 and the second header member 212 are joined to form the connection header 21. The brazing materials 22a located on the joining surfaces are in contact with each other, and the anticorrosion material 22c is on the outside, that is, the side from which the overhang portions 211d and 212d protrude. Thereby, while ensuring the brazing property of the 1st junction part 211f and the 2nd junction part 212f, the connection header 21 excellent in anticorrosion property can be obtained with the anticorrosion material 22c.

  Here, FIG. 16 shows a cross-sectional view when the brazing sheet 22 having a thickness QA of the first embodiment is pressed into a semicylindrical shape. When the shape is changed by pressing a sheet metal, the volume of the material does not change before and after the processing, so the plate thickness QB around the overhanging portion 211a becomes thin. That is, a high intensity | strength site | part and a low site | part arise. Therefore, in order to satisfy the pressure resistance, it is necessary to set the plate thickness of the first header member 211 and the second header member 212 to allow for the plate thickness change represented by QA-QB.

  The first header member 211 and the second header member 212 according to the present embodiment have continuous and stepped inner surfaces and outer surfaces of the overhang portions 211d and 212d. Therefore, as indicated by QB in FIG. 13, the thickness of the material after press working is locally reduced. Thereafter, at the time of brazing, the brazing material 22a around the staircase portion is aggregated into stepped corner portions due to surface tension. Thereby, as shown in FIG. 17, the minimum plate thickness after brazing becomes QC including the thickness of the brazing material 22a.

  As described above, in the heat exchanger 20 according to the present embodiment, the material of the first header member 211 and the second header member 212 is a brazing sheet in which brazing materials are laminated, and an overhang portion 211d, The inner surface and the outer surface of 212d have a continuous staircase shape. As a result, the brazing material agglomerates at the stepped corners, so that the strength reduction of the overhanging portions 211d and 212d can be suppressed. Therefore, since the pressure resistance can be satisfied without increasing the thickness of the first header member 211 and the second header member 212, the connection header 21 can be made light and inexpensive.

  In the present embodiment, the material of the first header member 211 and the second header member 212 is the brazing sheet 22 in which three kinds of materials are laminated, but is not limited thereto. For example, you may use the brazing sheet which laminated | stacked the brazing material 22a on both surfaces of the base material 22b. As a result, as shown in FIG. 18, the brazing material agglomerates at the stepped corners of both the inner surface and the outer surface of the first header member 211 and the second header member 212. Therefore, the connection header 21 with higher pressure resistance can be obtained.

  Although the overhang portions 211a and 212a according to the above-described embodiments are semicylindrical, the present invention is not limited thereto. The overhang portions 211a and 212a only need to be able to communicate with the heat transfer tube 20a to form a flow path of the heat medium. For example, as shown in FIG.

  In addition, the overhang portions 211a and 212a according to each of the above-described embodiments are integrally formed on the first header member 211 and the second header member 212 by press working. Absent. For example, as illustrated in FIG. 20, the overhanging portion 212a may be configured by a through hole 212g formed in the second header member 212 and a lid member 23 covering the through hole 212g. In this case, the lid member 23 may be brazed and joined to the first header member 211 and the second header member 212 in a state of being fixed to the second header member 212 in advance.

DESCRIPTION OF SYMBOLS 1 Outdoor unit, 10 housing | casing, 10a front panel, 10b side panel, 10c back panel, 10f separator plate, 11 exhaust port, 12a, 12b inlet port, 13 fan guard, 14 rear guard, 20 heat exchanger, 20a heat exchanger tube, 20b radiating fin, 20d refrigerant pipe, 21 connection header, 211 first header member, 212 second header member, 211a, 211d, 212a, 212d overhanging part, 211b, 211e insertion hole, 211c, 211f first joint part, 212c, 212f 2nd joint, 212g through hole, 22 brazing sheet, 22a brazing material, 22b base material, 22c anticorrosion material, 23 lid member, 60 fan, 61 motor, 62 fan frame, 100a machine room, 100b fan room, 200a, 200b Heat exchange unit

Claims (8)

A plurality of heat transfer tubes for circulating a heat medium;
A first header member having a plurality of insertion holes through which the heat transfer tubes are inserted, and a planar first joint portion;
A second header member having a planar second joining portion, joined to the first header member to form a flow path of the heat medium, and
At least one of the first header member and the second header member is
Having an overhanging portion for communicating a plurality of the heat transfer tubes;
The first joint and the second joint are joined;
Heat exchanger. The periphery of the overhang part is a planar joint part.
The heat exchanger according to claim 1. The overhang portion is
Having a semi-cylindrical shape,
The heat exchanger according to claim 1 or 2. The overhang portion is
At least one of the inner surface and the outer surface is a continuous stepped shape,
The heat exchanger according to any one of claims 1 to 3. At least one of the first header member and the second header member is
One surface is a corrosion protection layer and the other surface is a brazing sheet having a wax layer
The wax layer is
It is arranged on the joint surface between the first header member and the second header member,
The heat exchanger according to any one of claims 1 to 4. At least one of the first header member and the second header member is
It is a brazing sheet whose both sides are wax layers,
The heat exchanger according to any one of claims 1 to 4. At least one of the first header member and the second header member is
One surface is a brazing sheet with a wax layer,
The wax layer is
It is arranged on the joint surface between the first header member and the second header member,
The heat exchanger according to any one of claims 1 to 4. The heat transfer tube has a flat shape,
The gap distance between the tip of the heat transfer tube inserted into the first header member and the second header member facing the tip is equal to or greater than the flat portion thickness of the heat transfer tube.
The heat exchanger according to any one of claims 1 to 7.

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