JP2022090275A - Heat exchanger and water heater - Google Patents

Abstract

To provide a heat exchanger capable of inhibiting a brazing filler metal that has dropped from a heat exchange part located on the upper side from joining a side of a cantilever meandering pipe included in a heat exchange part located on the lower side, which is not supported by a case, and the case to each other, and bending of the side of the meandering pipe that is not supported by the case.SOLUTION: A heat exchanger includes: a case having a first side wall and a second side wall which oppose to each other leaving a gap in a first direction and a third side wall and a fourth side wall which oppose to each other leaving a gap in a second direction orthogonal to the first direction; a first heat exchange part and a second heat exchange part that are accommodated in the case and superposed on each other in a third direction orthogonal to the first direction and the second direction; and a support plate mounted onto an inner wall surface of the first side wall.SELECTED DRAWING: Figure 5

Description

The present invention relates to a heat exchanger and a water heating device.

Patent Document 1 (Patent No. 376792) describes a heat exchanger. The heat exchanger described in Patent Document 1 has a case and a heat transfer tube. The case has a first side wall and a second side wall that face each other at a distance, and a third side wall and a fourth side wall that face each other at a distance. The heat transfer tube extends along the direction in which the first side wall and the second side wall face each other. Both ends of the heat transfer tube are attached to the first side wall and the second side wall by brazing, respectively.

Patent Document 2 (Japanese Unexamined Patent Publication No. 2020-3108) describes a heat exchanger. The heat exchanger described in Patent Document 2 has a case, a heat transfer tube, and a body tube. The case has a first side wall and a second side wall that face each other at a distance, and a third side wall and a fourth side wall that face each other at a distance. The heat transfer tube extends along the direction in which the first side wall and the second side wall face each other. Both ends of the heat transfer tube are attached to the first side wall and the second side wall by brazing, respectively. The body tube extends along the inner wall surfaces of the third side wall, the first side wall and the fourth side wall, and is attached to the inner wall surface by brazing.

Japanese Patent No. 376792 Japanese Unexamined Patent Publication No. 2020-3108

Inside the case, a heat exchange unit that functions as a primary heat exchanger and a heat exchange that functions as a secondary heat exchanger may be arranged so as to overlap each other in the vertical direction. In this case, since brazing to the heat exchange part above and brazing to the heat exchange part below are performed collectively, the brazing material is transferred from the heat exchange part above to the heat exchange part below. May hang down.

The heat transfer tube of the lower heat exchange section is a meandering tube, and the meandering tube may be cantilevered on the side wall of the case. In this case, the meandering tube may be softened by heating during brazing, and the end portion not supported by the side wall of the case may be bent by its own weight. In addition, the end of the meandering tube that is not supported by the side wall of the case and the side wall of the case that does not support the meandering tube may be joined by the brazing material dripping from the heat exchange portion above. be. In this case, the portion of the meandering pipe joined by the brazing material may be damaged due to the water hammer phenomenon.

In the heat exchangers described in Patent Document 1 and Patent Document 2, a heat exchange unit functioning as a primary heat exchanger and a heat exchange unit functioning as a secondary heat exchanger are arranged vertically on top of each other inside the case. Not. Further, in the heat exchangers described in Patent Document 1 and Patent Document 2, a meandering tube is not used for the heat transfer tube.

In the present invention, when brazing is performed, the brazing material dripping from the heat exchange section above is included in the heat exchange section below, and the side and the case are not supported by the case of the cantilevered meandering tube. Provided are heat exchangers and hot water devices capable of suppressing joining and bending of the side not supported by the case of the meandering tube.

The heat exchanger of the present invention faces the first side wall and the second side wall which face each other at a distance in the first direction and the second side wall which faces each other at a distance in the second direction orthogonal to the first direction. A case having a third side wall and a fourth side wall, and a first heat exchange unit and a first heat exchange unit housed in the case and arranged so as to be overlapped with each other in the third direction orthogonal to the first direction and the second direction. (2) A heat exchange portion and a support plate attached to the inner wall surface of the first side wall are provided. The first heat exchange unit has a plurality of first heat transfer tubes arranged so as to be stacked along the second direction. Each of the plurality of first heat transfer tubes includes a plurality of straight tube portions, a plurality of first curved tube portions, and a plurality of second curved tube portions. The plurality of straight pipe portions are arranged in a row along the third direction. Each of the plurality of straight pipe portions extends along the first direction. Each of the plurality of first curved pipe portions connects one end in the first direction of two of the plurality of straight pipe portions adjacent to each other in the third direction. Each of the plurality of second curved pipe portions is located at other than both ends in the third direction, and connects the other ends of the plurality of straight pipe portions adjacent to each other in the third direction in the first direction. The other end of each of the plurality of straight pipe portions located at both ends in the third direction in the first direction is supported by the second side wall. The second heat exchange unit has a plurality of second heat transfer tubes extending along the first direction. Both ends of each of the plurality of second heat transfer tubes in the first direction are brazed to the first side wall and the second side wall, respectively. The support plate has a support portion that supports a plurality of first curved pipe portions along a third direction, and a brazing receiving portion. The brazing receiving portion is formed by bending the end portion of the support plate on the second heat exchange portion side in the third direction, and forms an acute angle with the inner wall surface of the first side wall.

In the above heat exchanger, the support portion may be formed by cutting the support portion from the support plate.

In the above heat exchanger, the support portion may be inclined so that the tip end is closer to the second heat exchange portion than the base end.

In the above heat exchanger, the support portion may include a narrow portion on the distal end side whose width becomes narrower as it approaches the distal end.

The water heating device of the present invention includes the above heat exchanger and a combustion device that supplies combustion gas to the above heat exchanger.

According to the heat exchanger and hot water apparatus of the present invention, when brazing is performed, the brazing material dripping from the heat exchange part at the upper part is supported by the case of the cantilevered meandering tube included in the heat exchange part at the lower part. It is possible to prevent the side that is not brazed from joining the case and the side that is not supported by the case of the meandering tube from bending.

It is a 1st perspective view of a heat exchanger 100. 2 is a second perspective view of the heat exchanger 100. It is a front view of the heat exchanger 100. It is sectional drawing in IV-IV of FIG. It is sectional drawing in VV of FIG. It is an enlarged view of FIG. It is a perspective view of the support plate 50 in the heat exchanger 100. It is a schematic diagram of a hot water apparatus 200. It is an enlarged sectional view of the heat exchanger 100 which concerns on modification 1. FIG. It is a perspective view of the support plate 50 in the heat exchanger 100 which concerns on modification 2. FIG.

The details of the embodiment of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding parts are designated by the same reference numerals, and duplicate explanations are not repeated.

(Structure of heat exchanger according to the embodiment)
The configuration of the heat exchanger (referred to as “heat exchanger 100”) according to the embodiment will be described below.

FIG. 1 is a first perspective view of the heat exchanger 100. FIG. 2 is a second perspective view of the heat exchanger 100. FIG. 3 is a front view of the heat exchanger 100. FIG. 4 is a cross-sectional view taken along the line IV-IV of FIG. FIG. 5 is a cross-sectional view taken along the line VV of FIG. In FIG. 4, illustrations other than the case 10, the first heat transfer tube 21, and the support plate 50 are omitted. FIG. 6 is an enlarged view of FIG. FIG. 7 is a perspective view of the support plate 50 in the heat exchanger 100. As shown in FIGS. 1 to 7, the heat exchanger 100 includes a case 10, a first heat exchange unit 20, a second heat exchange unit 30, and a support plate 50.

The case 10 has a first side wall 11, a second side wall 12, a third side wall 13, a fourth side wall 14, and a bottom wall 15. The first side wall 11 and the second side wall 12 face each other with a gap. The direction in which the first side wall 11 and the second side wall 12 face each other is referred to as the first direction DR1. The third side wall 13 and the fourth side wall 14 face each other with a gap. The direction in which the third side wall 13 and the fourth side wall 14 face each other is referred to as the second direction DR2. The second direction DR2 is orthogonal to the first direction DR1. Although not shown, an exhaust port 13a is formed on the third side wall 13. The exhaust port 13a penetrates the third side wall 13 along the thickness direction.

The direction orthogonal to the first direction DR1 and the second direction DR2 is referred to as a third direction DR3. The case 10 has an opening 16 at one end in the third direction DR3 and an opening 17 at the other end in the third direction DR3. The opening 17 is closed by the bottom wall 15.

The first heat exchange unit 20 and the second heat exchange unit 30 are arranged so as to be overlapped with each other in the third direction DR3. The second heat exchange unit 30 is closer to the opening 16 than the first heat exchange unit 20 in the third direction DR3. The first heat exchange unit 20 functions as a secondary heat exchanger, and the second heat exchange unit 30 functions as a primary heat exchanger.

The first heat exchange unit 20 has a plurality of first heat transfer tubes 21. The first heat transfer tube 21 is a meandering tube that meanders in a plane orthogonal to the second direction DR2. The plurality of first heat transfer tubes 21 are arranged so as to be overlapped with each other along the second direction DR2. The two adjacent first heat transfer tubes 21 in the second direction DR2 are misaligned in the third direction DR3. The first heat transfer tube 21 is made of, for example, stainless steel.

The first heat transfer tube 21 has a plurality of straight tube portions 22, a plurality of first curved tube portions 23, and a plurality of second curved tube portions 24. The straight pipe portion 22 extends along the first direction DR1. The plurality of straight pipe portions 22 are arranged in a row along the third direction DR3.

Of the plurality of straight pipe portions 22, those at both ends in the third direction DR3 are referred to as straight pipe portions 22a and straight pipe portions 22b, respectively. The straight pipe portion 22a is closer to the opening 17 than the straight pipe portion 22a in the third direction DR3. Of the plurality of straight pipe portions 22, those other than both ends in the third direction DR3 are referred to as straight pipe portions 22c.

One end (the end on the first side wall 11 side) of two of the adjacent straight pipe portions 22 in the third direction DR3 in the first direction DR1 is connected by the first curved pipe portion 23. The other end of the straight pipe portion 22a in the first direction DR1 (the end on the second side wall 12 side) and the other end of the straight pipe portion 22b in the first direction DR1 are supported by the second side wall 12. From another point of view, the first heat transfer tube 21 is cantilevered by the case 10 (second side wall 12). The other end of two of the plurality of straight pipe portions 22c adjacent to each other in the third direction DR3 in the first direction DR1 is connected by the second curved pipe portion 24.

A header 25 and a header 26 are attached to the outer wall surface of the second side wall 12. The other end of the straight pipe portion 22a in the first direction DR1 is connected to the header 25. The header 25 is formed with a water inlet 27 communicating with the inside of the header 25. The other end of the straight pipe portion 22b in the first direction DR1 is connected to the header 26. The header 26 is formed with a water outlet 28 communicating with the inside of the header 26.

The second heat exchange unit 30 has a plurality of body tubes 31 and a plurality of second heat transfer tubes 32. The plurality of body tubes 31 are closer to the opening 16 than the plurality of second heat transfer tubes 32 in the third direction DR3. The body tube 31 and the second heat transfer tube 32 are made of, for example, stainless steel.

The plurality of body tubes 31 are arranged so as to be overlapped along the third direction DR3. The body tube 31 extends along the inner wall surface of the third side wall 13, the inner wall surface of the first side wall 11, and the inner wall surface of the fourth side wall 14. The body tube 31 is attached to the inner wall surface of the third side wall 13, the inner wall surface of the first side wall 11, and the inner wall surface of the fourth side wall 14 by brazing.

One end of the body tube 31 and the other end of the body tube 31 are supported by the second side wall 12. One end of the body tube 31 is on the third side wall 13 side, and the other end of the body tube 31 is on the fourth side wall 14 side. One end of the body pipe 31 closest to the opening 16 in the third direction DR3 is connected to the water outlet 28 by the connecting pipe 33. The other end of one body tube 31 is connected to one end of another body tube 31 adjacent to the body tube 31 in the third direction DR3 by a connecting tube 34.

The second heat transfer tube 32 extends along the first direction DR1. One end (the end on the first side wall 11 side) and the other end (the end on the second side wall 12 side) of the second heat transfer tube 32 in the first direction DR1 are attached to the first side wall 11 and the second side wall 12, respectively. ing. This installation is done by brazing.

The plurality of second heat transfer tubes 32 are arranged in a plurality of rows along the second direction DR2. In the plurality of second heat transfer tubes 32, for example, a plurality of second heat transfer tubes 32a arranged in a row along the second direction DR2 and a plurality of second heat transfer tubes 32a arranged in a row along the second direction DR2 are arranged side by side. A plurality of second heat transfer tubes 32b (not shown) are included. The second heat transfer tube 32a is closer to the opening 16 than the second heat transfer tube 32b in the third direction DR3.

Of the plurality of second heat transfer tubes 32a, the one on the fourth side wall 14 side is referred to as the second heat transfer tube 32aa. Of the plurality of second heat transfer tubes 32a, the one on the third side wall 13 side is referred to as a second heat transfer tube 32ab. Of the plurality of second heat transfer tubes 32b, the one on the fourth side wall 14 side is referred to as a second heat transfer tube 32ba. Of the plurality of second heat transfer tubes 32b, the one on the third side wall 13 side is referred to as a second heat transfer tube 32bb.

One end of two of the adjacent second heat transfer tubes 32a in the second direction DR2 in the first direction DR1 is connected by a connecting tube 35. The other ends of two of the adjacent second heat transfer tubes 32a in the second direction DR2 in the first direction DR1 are connected by a connecting tube 36. However, the other end of the second heat transfer tube 32aa in the first direction DR1 is connected to the other end of the body tube 31 farthest from the opening 16 in the third direction DR3 by the connecting tube 37. Further, one end of the second heat transfer tube 32ab in the first direction DR1 is connected to one end of the second heat transfer tube 32bb in the first direction DR1 by the connecting tube 38.

One end of two adjacent second heat transfer tubes 32b in the first direction DR1 in the second direction DR2 is connected by a connecting tube 39. However, one end of the connecting tube 40 is connected to one end of the second heat transfer tube 32ba. The other ends of two of the adjacent second heat transfer tubes 32b in the second direction DR2 in the first direction DR1 are connected by a connecting tube 41. However, as described above, one end of the second heat transfer tube 32bb in the first direction DR1 is connected to one end of the second heat transfer tube 32ab in the first direction DR1 by the connecting tube 38. The other end of the connecting pipe 40 is a water outlet 42.

A plurality of fins 32c are attached to the second heat transfer tube 32. The fins 32c are attached by brazing. The fin 32c is made of, for example, stainless steel. One main surface of the fin 32c faces the first side wall 11, and the other main surface of the fin 32c faces the second side wall 12. The plurality of fins 32c are arranged at intervals in the first direction DR1. In the figure, only a part of the fins 32c is shown, and the remaining fins 32c are not shown.

The support plate 50 is attached to the inner wall surface of the first side wall 11. The support plate 50 is attached to the first side wall 11 by, for example, spot welding. The support plate 50 has a support portion 51 and a brazing receiving portion 52. The support plate 50 is made of, for example, stainless steel.

The support portion 51 supports the first curved pipe portion 23. This support is provided along the third direction DR3. The support portion 51 is formed by cutting up the support plate 50. That is, except for the portion that becomes the base end of the support portion 51, the portion that becomes the support portion 51 and the portion around it are cut, and the portion that becomes the support portion 51 is bent to the side opposite to the first side wall 11. Therefore, the support portion 51 is formed. As a result, the opening 51a is formed at a position adjacent to the support portion 51 in the third direction DR3. The support portion 51 extends along the first direction DR1.

The portion of the first curved pipe portion 23 having the minimum distance from the first side wall portion 11 of the first curved pipe portion 23 faces the first side wall 11 with the support plate 50 interposed therebetween. From another point of view, the end of the opening 51a on the opposite side of the support portion 51 has the first curved pipe portion having the minimum distance from the first side wall 11 of the first curved pipe portion 23. It is closer to the support 51 than the 23 portion.

The brazing receiving portion 52 is formed by bending the end portion of the support plate 50 on the second heat exchange portion 30 side to the side opposite to the first side wall 11. The brazing receiver 52 is located between the first heat exchange section 20 and the second heat exchange section 30 in the third direction DR3. The brazing receiving portion 52 extends so as to form an acute angle (an angle of more than 0 ° and less than 90 °) with the inner wall surface of the first side wall 11 in a cross-sectional view orthogonal to the second direction DR2. ..

(Structure of hot water device according to embodiment)
Hereinafter, the configuration of the hot water device (referred to as “hot water device 200”) according to the embodiment will be described.

FIG. 8 is a schematic diagram of the hot water device 200. As shown in FIG. 7, the water heater 200 has a heat exchanger 100. The hot water device 200 further includes a gas valve 110, an orifice 111, a venturi 112, a blower 113, a chamber 114, a burner 115, a spark plug 116, a duct 120, a pipe 130, a pipe 140, and a bypass. It has a pipe 150 and a three-way valve 160.

By opening the gas valve 110, the fuel gas is supplied to the venturi 112 through the orifice 111. The fuel gas supplied to the Venturi 112 is mixed with air in the Venturi 112 (hereinafter, the fuel gas mixed with the air is referred to as a mixed gas). The mixed gas is supplied to the burner 115 through the chamber 114 by the blower 113.

The mixed gas supplied to the burner 115 is ignited and burned by sparking the spark plug 116. As a result, combustion gas is generated in the burner 115. The burner 115 is attached to the heat exchanger 100. More specifically, the burner 115 is attached to the opening 16. Therefore, the combustion gas generated by the burner 115 flows inside the case 10 from the opening 16 side toward the opening 17 side.

The pipe 130 is connected to the water supply at one end. The pipe 130 is connected to the water inlet 27 at the other end. The pipe 140 is connected to the water outlet 42 at one end. The pipe 140 is connected to a hot water tap (not shown) at the other end.

The bypass pipe 150 is connected to the pipe 130 at one end and to the pipe 140 at the other end. The connection between the bypass pipe 150 and the pipe 140 is made by a three-way valve 160. The duct 120 is connected to the heat exchanger 100. More specifically, the duct 120 is connected to the exhaust port 13a.

The water supplied from one end of the pipe 130 flows through the pipe 130 and is supplied to the first heat exchange unit 20 (first heat transfer tube 21). The water supplied to the first heat exchange unit 20 is heated by exchanging heat with the combustion gas. The water that has flowed through the first heat exchange section 20 flows through the connecting pipe 33 and is supplied to the second heat exchange section 30 (body tube 31 and second heat transfer tube 32).

The water supplied to the second heat exchange unit 30 is heated by exchanging heat with the combustion gas. The water flowing through the second heat exchange unit 30 flows through the pipe 140 and is supplied from the hot water tap. The temperature of the water (hot water) supplied from the hot water tap is adjusted by mixing the water flowing through the second heat exchange unit 30 with the clean water supplied from the bypass pipe 150 in the pipe 140. The combustion gas that has exchanged heat with the water flowing through the first heat exchange unit 20 and the second heat exchange unit 30 is discharged to the outside from the duct 120.

(Effect of heat exchanger according to the embodiment)
The effect of the heat exchanger 100 will be described below.

In the heat exchanger 100, since a plurality of heat exchange units (first heat exchange unit 20 and second heat exchange unit 30) are housed in the case 10, brazing to the heat exchanger 100 is performed collectively. Will be. At the time of this brazing, the heat exchanger 100 is arranged in the furnace so that the third direction DR3 coincides with the vertical direction.

When the brazing receiving portion 52 is not provided, the brazing material for attaching the second heat transfer tube 32 to the first side wall 11 hangs down during this brazing, and the inner wall surface of the first curved tube portion 23 and the first side wall 11 is provided. It may be joined by the brazing material that hangs down. When the first curved pipe portion 23 and the inner wall surface of the first side wall 11 are joined by a sagging brazing material, the first side wall 11 is formed by the brazing material due to the water hammer phenomenon when water flows through the first curved pipe portion 23. The portion of the first curved pipe portion 23 joined to the inner wall surface of the above may be damaged.

However, the heat exchanger 100 is provided with a brazing receiving portion 52. Therefore, the brazing material hanging from the second heat transfer tube 32 is received by the brazing receiving portion 52 and flows between the support plate 50 and the inner wall surface of the first side wall 11. As a result, according to the heat exchanger 100, the bonding between the first curved pipe portion 23 and the inner wall surface of the first side wall 11 due to the brazing material dripping from the heat exchange portion (second heat exchange portion 30) above is prevented. As a result, damage to the first curved pipe portion 23 when water flows is suppressed.

Further, the first heat transfer tube 21 is cantilevered and supported by the second side wall 12. Therefore, the first heat transfer tube 21 softens as the temperature rises during brazing, and one end side of the straight tube portion 22 not supported by the first side wall 11 in the first direction DR1 bends downward. ..

In the heat exchanger 100, since the first curved tube portion 23 is supported by the support portion 51 along the third direction DR3, even if the first heat transfer tube 21 is softened during brazing, the straight tube portion 22 One end side in the first direction DR1 of the above is hard to bend downward.

As described above, the brazing filler metal dripping from the second heat transfer tube 32 flows between the support plate 50 and the inner wall surface of the first side wall 11. Therefore, when the portion of the first curved pipe portion 23 that minimizes the distance between the first curved pipe portion 23 and the first side wall portion 23 faces the first side wall 11 with the support plate 50 interposed therebetween (opening). The end of the portion 51a opposite to the support portion 51 is closer to the support portion 51 than the portion of the first curved pipe portion 23 having the minimum distance from the first side wall 11 of the first curved pipe portion 23. (Case), the brazing material dripping from the second heat exchange portion 30 makes it more difficult to join the first curved pipe portion 23 and the inner wall surface of the first side wall 11.

(Modification 1)
FIG. 9 is an enlarged cross-sectional view of the heat exchanger 100 according to the first modification. FIG. 9 shows a cross section of the position corresponding to VV in FIG. As shown in FIG. 9, the support portion 51 may be inclined so that the tip thereof is closer to the second heat exchange portion 30 than the proximal end. From another point of view, the support portion 51 may extend so as to form an acute angle with the inner wall surface of the first side wall 11 in a cross-sectional view orthogonal to the second direction DR2. The angle formed by the support portion 51 and the inner wall surface of the first side wall 11 is, for example, 85 ° or more and less than 90 °. This angle may be 87 ° or more and less than 90 °.

In this case, the brazing material dripping from the second heat exchange section 30 (second heat transfer tube 32) travels along the support section 51 and becomes difficult to reach the vicinity of the first curved tube section 23. Further, in this case, it is possible to further suppress the one end side of the straight pipe portion 22 in the first direction DR1 from bending downward.

(Modification 2)
FIG. 10 is a perspective view of the support plate 50 in the heat exchanger 100 according to the second modification. As shown in FIG. 10, the support portion 51 may have a narrow width portion 51b on the tip end side. The width of the narrow width portion 51b (width in the second direction DR2) becomes narrower as it approaches the tip end side. The narrow width portion 51b may have, for example, a triangular shape. As described above, since the support portion 51 is formed by cutting up the support plate 50, the end portion of the opening 51a opposite to the support portion 51 has the same shape as the narrow width portion 51b. Will be there.

In this case, the brazing material flowing between the support plate 50 and the inner wall surface of the first side wall 11 bypasses the opening 51a (see the arrow in FIG. 10), so that the first curve passes through the opening 51a. It becomes more difficult to reach the vicinity of the pipe portion 23.

Although the embodiment of the present invention has been described above, it is possible to modify the above-described embodiment in various ways. Moreover, the scope of the present invention is not limited to the above-described embodiment. The scope of the present invention is indicated by the scope of claims and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

This embodiment is particularly advantageously applied to a heat exchanger in which a plurality of heat exchangers are included in a case and a hot water device having the same.

10 Case, 11 1st side wall, 12 2nd side wall, 13 3rd side wall, 13a exhaust port, 14 4th side wall, 15 bottom wall, 16,17 openings, 20 1st heat exchange part, 21 1st heat transfer tube, 22, 22a, 22b, 22c Straight pipe part, 23 1st curved pipe part, 24 2nd curved pipe part, 25, 26 header, 27 water inlet, 28 water outlet, 30 2nd heat exchange part, 31 body pipe, 32 , 32a, 32aa, 32ab, 32b, 32ba, 32bb 2nd heat transfer tube, 32c fin, 33, 34, 35, 36, 37, 38, 39, 40, 41 connection pipe, 42 outlet, 50 support plate, 51 support Part, 51a opening, 51b narrow part, 52 brazing part, 100 heat exchanger, DR1 1st direction, DR2 2nd direction, DR3 3rd direction, 110 gas valve, 111 orifice, 112 venturi, 113 blower, 114 Chamber, 115 burner, 116 ignition plug, 120 duct, 130, 140 piping, 150 bypass piping, 160 three-way valve, 200 hot water device.

Claims (6)

The first side wall and the second side wall facing each other at intervals in the first direction, and the third side wall and the fourth side wall facing each other at intervals in the second direction orthogonal to the first direction. A case with a side wall and
The first heat exchange section and the second heat exchange section, which are housed in the case and are arranged so as to be overlapped with each other in the first direction and the third direction orthogonal to the second direction.
A support plate attached to the inner wall surface of the first side wall is provided.
The first heat exchange unit has a plurality of first heat transfer tubes arranged so as to be stacked along the second direction.
Each of the plurality of first heat transfer tubes includes a plurality of straight tube portions, a plurality of first curved tube portions, and a plurality of second curved tube portions.
The plurality of straight pipe portions are arranged so as to form a row along the third direction.
Each of the plurality of straight pipe portions extends along the first direction.
Each of the plurality of first curved pipe portions connects one end in the first direction of two of the plurality of straight pipe portions adjacent to each other in the third direction.
Each of the plurality of second curved pipe portions is located at other than both ends in the third direction, and two of the plurality of straight pipe portions adjacent to each other in the third direction are the other ends in the first direction. Connected and
The other end in the first direction of each of the plurality of straight pipe portions located at both ends in the third direction is supported by the second side wall.
The second heat exchange unit has a plurality of second heat transfer tubes extending along the first direction.
Both ends of each of the plurality of second heat transfer tubes in the first direction are brazed to the first side wall and the second side wall, respectively.
The support plate has a support portion that supports the plurality of first curved pipe portions along the third direction, and a brazing receiving portion.
The brazing receiving portion is formed by bending the end portion of the support plate on the second heat exchange portion side in the third direction, and has an acute angle with the inner wall surface of the first side wall. Exchanger. The heat exchanger according to claim 1, wherein the support portion is formed by cutting up the support portion from the support plate. The heat exchanger according to claim 2, wherein the support portion is inclined so that the tip thereof is closer to the second heat exchange portion than the base end. The heat exchanger according to claim 2, wherein the support portion includes a narrow portion whose width becomes narrower toward the tip on the tip side. The portion according to any one of claims 2 to 4, wherein the portion of each of the first curved pipe portions having the minimum distance from the inner wall surface of the first side wall faces the support plate. Heat exchanger. The heat exchanger according to any one of claims 1 to 5.
A hot water device including a combustion device that supplies combustion gas to the heat exchanger.

Images