Heat exchanger and water heating device equipped with the same

Abstract

To provide a heat exchanger which can properly prevent or suppress blazing of a heat transmission pipe in an inappropriately warped condition due to its own weight.SOLUTION: A heat exchanger HE includes: a case C which has a first sidewall part 1 standing in a vertical height direction and into which a heating medium is supplied; and heat transmission pipes 6A, 6B for hot-water heating accommodated in the case C, where with opposite longitudinal end parts 60a, 60b of the heat transmission pipes 6A, 6B being joined to the first sidewall part 1 via brazing parts Ba, Bb, and the heat transmission pipes 6A, 6B being supported on the first sidewall part 1. The heat exchanger further comprises heat transmission pipe supporting parts 11a to 11c which are arranged on the first sidewall part 1 and can support regions of the heat transmission pipes 6A, 6B that are closer to the first sidewall part 1 so that the regions of the heat transmission pipes 6A, 6B closer to the first sidewall part 1 are prevented from descending downwardly below a first prescribed height.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a heat exchanger used as a component of a hot water device such as a water heater, which heats hot water by recovering heat from a heating medium such as combustion gas using a heat transfer tube, and to a hot water device equipped with the same. [Background technology]

[0002] A widely known heat exchanger used in hot water systems has a heat transfer tube housed in a case to which a heating medium such as combustion gas is supplied, and is capable of heating hot water flowing through the heat transfer tube. Specific examples of such heat exchangers include those described in Patent Documents 1 and 2. In the heat exchangers described in Patent Documents 1 and 2, a plurality of holes are formed in a predetermined side wall portion of the case, and both longitudinal ends of the heat transfer tubes are inserted into these holes for brazing. In this configuration, the heat transfer tubes are supported by the side wall portion of the case. Therefore, unless some countermeasures are taken, there is a risk of distortion, in which parts of the longitudinal middle portion of the heat transfer tubes are distorted downward due to their own weight during the brazing process to manufacture the heat exchanger. If brazing is performed while such distortion exists, the influence of the distortion may persist even after the brazing process is completed, resulting in significant errors in the positioning of each part of the heat transfer tube. This can lead to problems such as reduced heat exchange efficiency, and therefore it is necessary to appropriately avoid this risk. While the above-mentioned problems could be resolved if the orientation or posture of the heat exchanger could be appropriately changed to prevent the heat transfer tubes from significantly shifting out of position due to their own weight during the brazing process, this is sometimes not possible for various reasons.

[0003] Therefore, in the measure shown in Figure 8 of Patent Document 1, an upward protrusion is provided on the bottom wall of the case to support the heat transfer tube. This makes it possible to prevent the heat transfer tube from shifting position. However, depending on the specifications of the heat exchanger, the bottom of the case may be open and the case may not have a bottom wall. In such cases, it is difficult to provide the above-mentioned upward protrusion. Furthermore, if the heat transfer tube is positioned significantly above the bottom wall of the case, the size of the upward protrusion provided on the bottom wall must be large, which may result in problems such as an increase in the weight of the case.

[0004] On the other hand, in Patent Document 2, a heat transfer tube support portion that abuts against the heat transfer tube and supports the abutting portion is provided on the side wall portion of the case or an auxiliary member arranged inside the side wall portion. With this configuration, unlike Patent Document 1, even if the case does not have a bottom wall portion, it is possible to prevent distortion of the heat transfer tube during the brazing operation, and it is possible to solve the problems described in Patent Document 1.

[0005] However, Patent Document 2 still has room for improvement, as will be described below. That is, in Patent Document 2, the heat transfer tube support is provided on the side wall of the case or on an auxiliary member arranged inside the side wall. However, the side wall of the case is not the side wall (first side wall) to which both longitudinal ends of the heat transfer tube are brazed, but a different side wall. Therefore, it may be difficult for the heat transfer tube support to appropriately prevent the portion of the heat transfer tube near the first side wall from distorting downward due to its own weight. As a result, even in Patent Document 2, the heat transfer tube may be brazed to the side wall of the case in a distorted state, resulting in an error in the placement of the heat transfer tube. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2013-47575 A (Fig. 8) [Patent Document 2] Japanese Patent Publication No. 2020-70937 [Patent Document 3] Patent No. 4246749 [Patent Document 4] Japanese Patent Application Publication No. 2019-158235 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention was conceived under the circumstances described above, and aims to provide a heat exchanger that can appropriately prevent or suppress the heat transfer tubes from being brazed in an unduly distorted state due to their own weight, and that can prevent large errors in the placement of the heat transfer tubes, as well as a hot water device equipped with the same. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention provides the following technical solutions.

[0009] A heat exchanger according to a first aspect of the present invention comprises a case having a first side wall portion standing in a vertical direction and into which a heating medium is supplied, and a heat transfer tube for heating hot and cold water housed in the case, wherein both longitudinal ends of the heat transfer tube are joined to the first side wall portion via brazing portions and the heat transfer tube is supported by the first side wall portion, and further comprises a heat transfer tube support portion provided on the first side wall portion and capable of supporting a portion of the heat transfer tube close to the first side wall portion so as to prevent the portion of the heat transfer tube close to the first side wall portion from descending below a first predetermined height. the case has a second side wall portion facing and spaced from the first side wall portion, and further includes a heat transfer tube support member capable of supporting a portion of the heat transfer tube close to the second side wall portion so as to prevent the portion of the heat transfer tube close to the second side wall portion from descending below a second predetermined height, the heat transfer tube support member having a plate-like portion positioned within the case in an upright position in a vertical height direction which is the flow direction of the heating medium, and an opening portion formed in the plate-like portion through which the portion of the heat transfer tube close to the second side wall portion is inserted. It is characterized by the presence of

[0010] With this configuration, the heat transfer tube supports provided on the first side wall of the case can be used to appropriately prevent the heat transfer tube from significantly lowering due to its own weight during brazing in the heat exchanger manufacturing process. As a result, the heat transfer tubes can be prevented from being brazed in a significantly distorted state, and large errors in the placement of the heat transfer tubes can be prevented. During the brazing operation, the heat exchanger only needs to be oriented or positioned in the same way as it will be when it is used, which provides excellent versatility. Furthermore, this configuration appropriately prevents the portion of the heat transfer tube near the first side wall from significantly lowering due to its own weight during brazing, as well as the portion of the heat transfer tube near the second side wall, thereby more thoroughly preventing the heat transfer tube from being brazed in an unduly distorted state. Furthermore, this configuration simplifies the configuration of the support for the heat transfer tube, while accurately positioning and fixing (preventing distortion) the portion of the heat transfer tube near the second side wall portion. It also prevents the plate-like portion of the support for the heat transfer tube from significantly impeding the flow of the heating medium.

[0011] In the present invention, preferably, the heat transfer tube support portion is formed as a convex portion integrally formed with the first side wall portion so that a part of the first side wall portion partially protrudes toward the inside of the case.

[0012] According to this configuration, the heat transfer tube support can be easily and rationally provided on the first side wall of the case by performing press work to partially form the convex portion. There is no need to configure the heat transfer tube support as a separate member. Therefore, there is no increase in the number of parts or weight, and manufacturing costs can be suppressed. Furthermore, the formation of the heat transfer tube support is expected to have the effect of increasing the strength of the first side wall of the case.

[0017] In the present invention, preferably, the heat transfer tubes comprise a plurality of serpentine heat transfer tubes, each of which extends in a direction intersecting the vertical height direction and is formed by a plurality of straight tube sections arranged at intervals in the vertical height direction and connected in series via a plurality of connecting tube sections, and the plurality of heat transfer tubes are arranged in the width direction of the case, and the heat transfer tube support sections comprise a plurality of heat transfer tube support sections that face and contact or face and approach the undersides of the plurality of connecting tube sections that are located near the first side wall section among the plurality of heat transfer tubes. Here, the "direction intersecting the vertical height direction" in the present invention includes not only the horizontal direction but also directions inclined at an appropriate angle above or below the horizontal direction.

[0018] According to this configuration, the serpentine heat transfer tubes can be used to increase the amount of heat recovered from the heating medium, which is preferable for improving the heat exchange efficiency of the heat exchanger. Meanwhile, during the brazing operation, the heat transfer tube supports appropriately prevent the connecting pipe portions located near the first side wall portion of the heat transfer tubes from unduly descending due to gravity.

[0019] In the present invention, preferably, at least one of the plurality of heat transfer tube support parts is provided in a form extending in the width direction of the case so as to be in opposing contact with or in close proximity to the lower surfaces of the plurality of connecting pipe parts.

[0020] According to such a configuration, the total number of heat transfer tube supports can be reduced and the configuration can be simplified, which is preferable in terms of facilitating the work of forming the heat transfer tube supports.

[0021] In the present invention, preferably, additional heat transfer tubes are arranged in an area within the case different from the area where the heat transfer tubes are arranged, and heat can be recovered from the heating medium by both these heat transfer tubes and the additional heat transfer tubes, and the additional heat transfer tubes have multiple tube body portions that penetrate multiple fins arranged in a direction that intersects the vertical height direction, and these multiple tube body portions and the multiple fins are joined to each other via additional brazing portions.

[0022] A heat exchanger having such a configuration is preferable for improving the heat exchange efficiency of the heat exchanger because it can recover heat from the heating medium using both the heat transfer tube and the additional heat transfer tube. On the other hand, to properly form the additional brazing portions for joining the multiple tube portions of the additional heat transfer tube to the multiple fins, it is desirable to position the heat exchanger so that the multiple tube portions are horizontal, place brazing material on top of the tube portions, and heat and melt the brazing material. In such a case, the present invention can properly prevent the portion of the heat transfer tube near the first sidewall portion from significantly descending due to its own weight.

[0023] A water heating device provided according to a second aspect of the present invention is characterized by including the heat exchanger provided according to the first aspect of the present invention.

[0024] According to this configuration, the same effects as those described for the heat exchanger provided by the first aspect of the present invention can be obtained.

[0025] Other features and advantages of the present invention will become more apparent from the following description of the preferred embodiments of the invention, which proceeds with reference to the accompanying drawings. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a schematic perspective view showing an example of a heat exchanger according to the present invention. [Figure 2] FIG. 2 is an exploded perspective view of FIG. 1. [Figure 3] FIG. 2 is an explanatory diagram showing an example of a hot water device using the heat exchanger of FIG. 1, and the cross-sectional view shown by the solid line in the figure corresponds to the cross-sectional view taken along line III-III in FIG. [Figure 4] 4(a) is a cross-sectional view taken along line IVa-IVa in FIG. 3, and FIG. 4(b) is a partially enlarged cross-sectional view of FIG. [Figure 5] 4(a) is a cross-sectional view taken along the line Va-Va in FIG. 3, and FIG. 4(b) is an enlarged cross-sectional view of a portion of FIG. [Figure 6] 6(a) is a perspective view as a component drawing of a first side wall portion of the heat exchanger shown in FIG. 1, and FIG. 6(b) is a cross-sectional view taken along line VIb-VIb of FIG. 6(a). [Figure 7] FIG. 2(a) is a perspective view as a parts drawing of a support for a heat transfer tube incorporated in the heat exchanger shown in FIG. 1, and FIG. 2(b) is a front view of FIG. [Figure 8] FIG. 8(a) is a perspective view showing another example of the first side wall portion, and FIG. 8(b) is a cross-sectional view taken along line VIIIb-VIIIb of FIG. 8(a). [Figure 9] FIG. 10 is a schematic perspective view showing another example of a heat exchanger according to the present invention. [Figure 10] XX cross-sectional view of FIG. 9. [Figure 11] 10A is a cross-sectional view taken along line XIa-XIa in FIG. 10A, FIG. 10B is an explanatory diagram of the state in which the fin shown in FIG. 10A and the heat transfer tube are brazed together, and FIG. 10C is a cross-sectional view of a main part showing an example of a brazed portion (additional brazed portion) formed by the brazing of FIG. 10B. [Figure 12] FIG. 10 is a perspective view showing a part of a first side wall portion of the heat exchanger shown in FIG. 9. [Figure 13] FIG. 4 is a cross-sectional view of a main part showing another example of a heat exchanger of the present invention. [Figure 14] (a) is a plan cross-sectional view showing another example of a heat exchanger according to the present invention, (b) is a cross-sectional view taken along XIVb-XIVb of (a), (c) is a cross-sectional view taken along XIVc-XIVc of (a), and (d) is a right side view of (c). DETAILED DESCRIPTION OF THE INVENTION

[0027] Preferred embodiments of the present invention will now be described in detail with reference to the drawings.

[0028] The heat exchanger HE shown in Figures 1 to 5 includes a roughly rectangular cylindrical or frame-shaped case C with open upper and lower surfaces, a plurality of first and second heat transfer tubes 6A, 6B arranged within this case C, a pair of header sections 7a, 7b for inlet and outlet water, and a support 5 for the heat transfer tubes.

[0029] As shown in FIG. 3, a hot water apparatus WH using a heat exchanger HE is configured such that a burner 80 and another heat exchanger 81 are provided on the upper side of a case C, for example. The other heat exchanger 81 is a primary heat exchanger for recovering sensible heat, and is configured similarly to a heat exchange section using additional heat transfer tubes 3, which will be described later. In contrast, the heat exchanger HE is a secondary heat exchanger for recovering latent heat. In the hot water apparatus WH, the combustion gas (heating medium) generated by the burner 80 travels downward and passes through the heat exchangers 81 and HE in sequence, thereby recovering sensible heat and latent heat from the combustion gas in sequence, and the recovered heat is used to heat hot water, which is then supplied as the desired hot water. is supplied first.

[0030] As shown in Figure 2, the case C is configured by combining a case main body 2 that is roughly U-shaped when viewed from above and a first side wall 1 that serves as a side plate portion on which header portions 7a and 7b are provided. The case main body 2 has three side walls 20 (20a to 20c) that are connected in a generally U-shape in plan view so as to form a side opening 21 on one side. Of these, the side wall 20c that faces the first side wall 1 corresponds to the second side wall in the present invention. The first side wall 1 is welded to the case main body 2 so as to close the side opening 21. In addition, both longitudinal end portions 60a, 60b of the first and second heat transfer tubes 6A, 6B are passed through and joined to the first side wall 1, as will be described in detail later.

[0031] The first and second heat transfer tubes 6A and 6B are serpentine heat transfer tubes. More specifically, as shown in FIGS. 2 and 4, the first heat transfer tube 6A has a serpentine shape in which a plurality of straight tube sections 60 extending horizontally and spaced apart in the vertical direction are connected in series via a plurality of connecting tube sections 61 that are semicircular in side view (in FIG. 4, two first heat transfer tubes 6A are shown overlapping each other, making it difficult to distinguish between them, so one of them is indicated by a dotted pattern). Both longitudinal ends 60a of the first heat transfer tube 6A are inserted into holes 10a formed in the first side wall 1 and drawn out to the outside of the case C, and are connected to header sections 7a and 7b formed on the outer surface of the first side wall 1. The peripheral edges of the holes 10a in the first side wall 1 and the ends 60a of the first heat transfer tube 6A are joined to each other via brazing sections Ba. The multiple first heat transfer tubes 6A are arranged at intervals in the width direction within the case C. However, in order to increase the amount of heat recovery, the multiple first heat transfer tubes 6A are arranged in a staggered pattern with height differences provided between adjacent first heat transfer tubes 6A, as shown in Fig. 3 .

[0032] 2 and 5, the second heat transfer tube 6B has a serpentine shape, extending in a direction intersecting the vertical height direction while inclining vertically relative to the horizontal, with a plurality of straight tube sections 63 spaced apart in the vertical height direction and connected in series via a plurality of connecting tube sections 62 that are semicircular in side view. Similar to the first heat transfer tube 6A, both end sections 60b of the second heat transfer tube 6B are connected to the header sections 7a, 7b and joined to the first side wall section 1. This joining is achieved by inserting the end section 60b into a hole 10b formed in the first side wall section 1, and providing a brazing section Bb that joins the periphery of the hole 10b to the end section 60b.

[0033] The second heat transfer tube 6B has good drainage properties because each straight tube section 63 is inclined vertically, and even if the first heat transfer tube 6A freezes in winter, hot water can be supplied by circulating hot water through this second heat transfer tube 6B. Unheated hot water is supplied to the water inlet 70 of the header section 7a, and the hot water heated after passing through the first and second heat transfer tubes 6A, 6B reaches the header section 7b and is discharged from the hot water outlet 71. As shown in FIGS. 2 and 3, the second heat transfer tubes 6B are provided so as to be positioned on both the left and right outer sides of the plurality of first heat transfer tubes 6A in the width direction of the case C.

[0034] As shown in FIGS. 4 to 6, the first side wall portion 1 of the case C is provided with a plurality of heat transfer tube supporting portions 11a to 11c. These heat transfer tube supports 11a to 11c are provided to prevent the first and second heat transfer tubes 6A, 6B from dropping below a predetermined height (first predetermined height) at their locations near the first side wall 1. These supports are all formed integrally with the first side wall 1 by press working the first side wall 1, and are convex portions of the first side wall 1 that partially protrude toward the inside of the case C. Therefore, on the outer surface of the first side wall 1, the portions where the heat transfer tube supports 11a to 11c are provided are located inward of the case C. There is a recessed depression on the side.

[0035] The plurality of heat transfer tube supporting portions 11a to 11c will now be described in more detail. 3 and 4, the first heat transfer tubes 6A can be divided into two groups: an upper group with a higher staggered arrangement height and a lower group with a lower staggered arrangement height. The heat transfer tube supports 11a are individually provided on the lower sides of the connecting pipes 61 of the upper group of first heat transfer tubes 6A near the first side wall 1. The upper surfaces of the heat transfer tube supports 11a are in contact with or close to the lower surfaces of the connecting pipes 61, preventing the connecting pipes 61 from descending below a predetermined height.

[0036] The heat transfer tube supports 11b are located below the connecting pipes 61 of the lower-stage plurality of first heat transfer tubes 6A that are closer to the first side wall 1, and are arranged so that the upper surfaces of the heat transfer tube supports 11b are in opposing contact with or are close to the lower surfaces of the connecting pipes 61, thereby preventing the connecting pipes 61 from descending below a predetermined height. However, unlike the heat transfer tube supports 11a described above, the heat transfer tube supports 11b are not so-called point-like convex portions, but are convex portions that extend linearly in the width direction of the case C. Therefore, the heat transfer tube supports 11b are in opposing contact with or are close to the lower surfaces of the connecting pipes 61 that are at approximately the same height all at once.

[0037] 5, the heat transfer pipe supports 11c are located below the connecting pipes 62 of the pair of second heat transfer pipes 6B that are closer to the first side wall 1, and the upper surfaces of the heat transfer pipe supports 11c are in contact with or close to the lower surfaces of the connecting pipes 62, thereby preventing the connecting pipes 62 from descending below a predetermined height. The heat transfer pipe supports 11c are so-called point-like convex portions, similar to the heat transfer pipe supports 11a.

[0038] In FIG. 4, the heat transfer tube support 5 is a member that supports the portions of the plurality of first heat transfer tubes 6A that are close to the second side wall portion 20c and prevents these portions from descending below a predetermined height (second predetermined height), and is disposed within the case C. In this embodiment, as shown in FIG. 5, the support 5 does not support the second heat transfer tube 6B. Furthermore, no support is provided to support the portion of the second heat transfer tube 6B that is close to the second side wall portion 20c. This is because the second heat transfer tube 6B is shorter than the plurality of first heat transfer tubes 6A and is less likely to bend or deform due to its own weight. Therefore, there is little need to use the support 5 for the second heat transfer tube 6B. However, a support structure using the support 5 can be applied to the second heat transfer tube 6B as with the first heat transfer tube 6A.

[0039] As shown in FIGS. 4 and 7 , the heat transfer tube support 5 has a plate-like portion 50 extending in the vertical direction, and openings 51 formed in the plate-like portion 50 through which the portions of the first heat transfer tubes 6A near the second side wall portion 20c are inserted. The openings 51 correspond to the arrangement of the first heat transfer tubes 6A, and the support 5 regulates the position of the first heat transfer tubes 6A. Bent pieces 53 and flange pieces 54, which are bent relative to the plate-like portion 50, are appropriately connected to the outer periphery of the plate-like portion 50, and these portions are welded to appropriate locations on the case C to secure the support 5. The upper bent piece 53 is provided with a ventilation opening 52 to ensure the flow of combustion gas.

[0040] Next, the operation of the heat exchanger HE will be described.

[0041] When manufacturing the heat exchanger HE, a brazing operation is carried out to provide the brazed portions Ba and Bb. During this brazing operation, as shown in Figs. 4 and 5, the heat transfer tube supports 11a to 11c are arranged on the undersides of the connecting pipe portions 61 and 62 of the first and second heat transfer tubes 6A and 6B that are closer to the first side wall portion 1. For this reason, a furnace for the brazing operation is used. Even if the first and second heat transfer tubes 6A, 6B soften due to the applied heat, the connecting pipe portions 61, 62 near the first side wall portion 1 are properly supported by the heat transfer tube supports 11a-11c and are properly prevented from descending below a predetermined height due to their own weight. As a result, it is possible to appropriately avoid performing the brazing operation when the first and second heat transfer tubes 6A, 6B are significantly distorted due to their own weight, and to prevent significant errors in the positioning of the first and second heat transfer tubes 6A, 6B. If the brazing operation is performed when the first and second heat transfer tubes 6A, 6B are significantly distorted due to their own weight, the distortion may still affect the positioning of the first and second heat transfer tubes 6A, 6B even after the brazing operation is completed, and such errors may result in a decrease in heat exchange efficiency. In contrast, this embodiment can eliminate or reduce the above-mentioned risk. Furthermore, during the brazing operation, the orientation or posture of the heat exchanger HE can be set to the orientation or posture that it will have when it is in use, which provides excellent versatility.

[0042] In this embodiment, the heat transfer tube support 5 can prevent the portion of the first heat transfer tube 6A near the second side wall portion 20c from descending unduly significantly due to its own weight. This further reduces distortion of the first heat transfer tube 6A, thereby improving the positional accuracy of the first heat transfer tube 6A. Furthermore, the heat transfer tube support 5 can be made to have an excellent ability to maintain the position of the first heat transfer tube 6A, while having a simple overall shape.

[0043] In the heat transfer tube supports 11a, 11b described above, the heat transfer tube supports 11b extend linearly. This simplifies the overall configuration of the heat transfer tube supports 11a, 11b, facilitating processing and reducing processing costs compared to, for example, when all of the heat transfer tube supports 11a, 11b are formed as so-called point-like convex portions. Furthermore, the heat transfer tube supports 11a, 11b improve the strength of the first sidewall portion 1. However, if the heat transfer tube supports 11b extend linearly, they also function as reinforcing ribs, further enhancing the strength improvement effect. Unlike the present embodiment, if both the heat transfer tube supports 11a, 11b were formed linearly extending in the width direction, it would be difficult to properly support the predetermined connecting pipe portions 61 of the plurality of first heat transfer tubes 6A. However, this embodiment does not have such a drawback.

[0044] 8 to 14 show other embodiments of the present invention. In these figures, elements that are the same as or similar to those in the above embodiment are given the same reference numerals as in the above embodiment, and redundant explanations will be omitted.

[0045] 8, in addition to the heat transfer tube supporting portions 11a and 11c, the heat transfer tube supporting portion 11b is also formed as a so-called point-like convex portion. The present invention can also have such a configuration.

[0046] The heat exchanger HE1 shown in FIGS. 9 to 11 is configured as a so-called primary-secondary integrated heat exchanger, in which both the primary heat exchange section and the secondary heat exchange section are incorporated into a single case C1. More specifically, this heat exchanger HE1 has a case C1 that is larger than the case C of the previous embodiment, and a third heat transfer tube 3 and a shell pipe 39 are provided above the first and second heat transfer tubes 6A and 6B. As shown by the phantom lines in FIG. 10, a burner 80 is disposed above the case C1, and combustion gas is supplied downward into the case C1. The third heat transfer tube 3 corresponds to an example of an additional heat transfer tube as defined in the present invention and constitutes a primary heat exchange section that recovers sensible heat from the combustion gas. The first and second heat transfer tubes 6A and 6B constitute a secondary heat exchange section that recovers latent heat.

[0047] The body pipe 39 is arranged along the upper inner surface of the case C1, and as shown in FIG. 9, hot water discharged from the outlet 71 of the header 7b is sent to the body pipe 39 from the supply port 38. The hot water flows in the direction shown by the arrows in the figure, and also flows through the header sections 35a and 35b for the body pipe. The hot water flowing through these sections prevents the upper part of the case C1 from overheating. After passing through the body pipe 39, the hot water is then sent to the third heat transfer tube 3 where it is further heated before being discharged from the outlet 37. 10 and 11, the third heat transfer tube 3 has a plurality of straight tube sections 30 penetrating a plurality of plate-like fins 4 arranged horizontally, and a plurality of bent pipes 36 connecting the ends of the plurality of tube sections 30. The plurality of fins 4 and the tube section 30 are connected via brazing sections Bc (corresponding to the additional brazing section of the present invention) as shown in FIG. 11(c).

[0048] In this heat exchanger HE1, the first side wall 1A of the case C1 has a configuration as shown in Fig. 12, and the range Sa shown in the figure has the same configuration as the respective parts of the first side wall 1 shown in Fig. 6. In the range above the range Sa, holes 19a and 19b are provided for inserting the third heat transfer tube 3 and the body pipe 39, as described above.

[0049] When manufacturing the heat exchanger HE1, in addition to providing the brazing portions Ba and Bb described above, a brazing portion Bc is also provided. A method for providing this brazing portion Bc is, for example, as shown in Fig. 11(b), by placing brazing material B on the upper side of the tube portion 30, heating and melting it, and allowing the molten brazing material to flow along the outer peripheral surface of the tube portion 30 and the surfaces of the fins 4. In this case, the heat exchanger HE1 must be positioned as shown in Figs. 9 to 11 during the brazing operation. However, even when positioned in this manner, the presence of the heat transfer tube supports 11a to 11c appropriately prevents the first and second heat transfer tubes 6A and 6B from descending under their own weight and becoming significantly distorted.

[0050] In the heat exchanger HE2 shown in FIG. 13, a partition member 85 and a bottom wall portion 86 are assembled to a case C1, and an exhaust port 87 for exhaust gas is provided in a side wall portion 20d. More specifically, in this heat exchanger HE2, the arrangement area of ​​the first and second heat transfer tubes 6A, 6B is divided into first and second areas S1, S2 by a partition member 85. The combustion gas traveling downward inside the case C1 passes through the first area S1 and reaches the bottom wall portion 86, then makes a U-turn upward and enters the second area S2, and is then discharged to the outside through an exhaust port 87. The flow direction of the combustion gas may be changed as in this embodiment. Alternatively, a burner may be disposed below the heat exchanger so that the combustion gas travels upward inside the heat exchanger.

[0051] In the heat exchanger HE3 shown in FIG. 14, a plurality of heat transfer tubes 6C are arranged in a case C2 having sidewalls 20e, 20f formed with a combustion gas inlet 88a and an exhaust port 88b. These heat transfer tubes 6C are horizontally oriented serpentine tubes and are aligned at intervals in the vertical direction. That is, the heat transfer tubes 6C differ in orientation and arrangement from the first and second heat transfer tubes 6A, 6B described above. However, both ends 60c of each heat transfer tube 6C are joined to the first sidewall 1 of the case C2 via brazing portions Bd. The first sidewall 1 is also provided with headers 7c, 7d having a water inlet 70 and a water outlet 71, and the interiors of these headers communicate with the interiors of the heat transfer tubes 6C.

[0052] A plurality of heat transfer tube supports 11d are integrally formed by press working on the first side wall 1. These heat transfer tube supports 11d are convex portions that face and contact or face and approach the lower surfaces of the connecting pipes 61 of the plurality of heat transfer tubes 6C that are closer to the first side wall 1, and prevent the connecting pipes 61 from descending below a predetermined height. A heat transfer tube support 5A is also provided, and this support 5A has a plate-like portion 50 that is provided with a plurality of openings 51a through which the portions of the heat transfer tubes 6C closer to the second side wall 20c are inserted. In this embodiment as well, the effects intended by the present invention can be obtained.

[0053] The present invention is not limited to the above-described embodiment, and the specific configurations of the heat exchanger and the hot water device according to the present invention can be freely designed and modified in various ways within the intended scope of the present invention.

[0054] As the heat transfer tube, instead of a serpentine tube, for example, a U-shaped tube can be used, and also heat transfer tubes of other configurations, such as the spiral tube shown in Patent Document 1, can be used.

[0055] The heat transfer tube support portion is not limited to a specific shape or size as long as it can support the predetermined portion of the heat transfer tube so as to prevent the predetermined portion of the heat transfer tube from descending below a predetermined height due to its own weight. Furthermore, although it is desirable that the heat transfer tube support portion be formed integrally with the first side wall portion of the case, it is also possible to provide it as a separate member. Furthermore, since the heat transfer tube support portion is only required to be a portion that can prevent a predetermined portion of the heat transfer tube from descending below a predetermined height, it does not have to be arranged so as to abut against the predetermined portion of the heat transfer tube under normal conditions, and may be either in opposing contact or opposing proximity to the predetermined portion.

[0056] The heating medium referred to in the present invention is not limited to combustion gas generated by a burner, but may also be high-temperature exhaust gas, etc. The hot water device referred to in the present invention is a concept that includes hot water devices for hot water heating or snow melting, in addition to hot water supply devices for general hot water supply and hot water supply for baths. When manufacturing the heat exchanger according to the present invention, it is also possible to braze both longitudinal ends of the heat transfer tube to the first side wall portion while the heat transfer tube is simply supported by the first side wall portion (without other side wall portions of the case being attached to the first side wall portion). In this case, it is also possible to support the portion of the heat transfer tube opposite to the portion close to the first side wall portion using an appropriate jig. [Explanation of symbols]

[0057] HE,HE1~HE3 Heat exchanger WH water heater Ba~Bd Brazed part C, C1, C2 Case 1,1A First side wall portion (of the case) 11a to 11c: Support for heat transfer tube 20c Second side wall (of the case) 3 Heat Transfer Tubes (Additional Heat Transfer Tubes) 4 Fins 5 Support for heat transfer tubes 50 Plate-shaped part 51 Opening 6A Heat Transfer Tube (First Heat Transfer Tube) 6B Heat transfer tube (second heat transfer tube) 60 Straight tubular body 60a, 60b Ends (of heat transfer tubes) 61, 62 Connecting pipe body part (of heat transfer pipe) 63 Straight tube body (heat transfer tube)

Claims

1. a case having a first side wall portion standing in a vertical height direction and into which a heating medium is supplied; A heat transfer tube for heating hot and cold water housed in this case; It is equipped with a heat exchanger, wherein both longitudinal end portions of the heat transfer tube are joined to the first side wall portion via brazing portions, and the heat transfer tube is supported by the first side wall portion; a heat transfer tube support portion that is provided on the first side wall portion and that is capable of supporting a portion of the heat transfer tube that is close to the first side wall portion so as to prevent the portion of the heat transfer tube that is close to the first side wall portion from descending below a first predetermined height, the case has a second side wall portion facing and spaced apart from the first side wall portion, a support for the heat transfer tube that can support the portion of the heat transfer tube that is close to the second side wall portion so as to prevent the portion of the heat transfer tube that is close to the second side wall portion from descending below a second predetermined height, a support for the heat transfer tube having a plate-like portion positioned within the case in an upright position in the vertical direction, which is the flow direction of the heating medium, and an opening formed in the plate-like portion through which a portion of the heat transfer tube near the second side wall portion is inserted.

2. 2. The heat exchanger of claim 1, a heat exchanger, wherein the support portion for the heat transfer tube is formed as a convex portion integrally formed with the first side wall portion so that a portion of the first side wall portion partially protrudes toward the inside of the case.

3. 3. The heat exchanger according to claim 1 or 2, The heat transfer tubes include a plurality of serpentine heat transfer tubes, each of which extends in a direction intersecting the vertical height direction and is formed by a plurality of straight tube portions arranged at intervals in the vertical height direction and connected in series via a plurality of connecting tube portions, and the plurality of heat transfer tubes are arranged in the width direction of the case, the heat transfer tube support portions are provided with a plurality of heat transfer tube support portions that are in opposing contact with or in opposing proximity to undersurface portions of the plurality of connecting pipe body portions that are located closer to the first side wall portion among the plurality of heat transfer tubes.

4. 4. The heat exchanger according to claim 3, a heat exchanger, wherein at least one of the plurality of heat transfer pipe support portions is provided in a form extending in the width direction of the case so as to be in opposing contact with or in close proximity to the lower surface portions of the plurality of connecting pipe portions.

5. 5. A heat exchanger according to claim 1, additional heat transfer tubes are arranged in a region different from the region where the heat transfer tubes are arranged in the case, and heat can be recovered from the heating medium by both the additional heat transfer tubes and the additional heat transfer tubes; a heat exchanger, wherein the additional heat transfer tube has a plurality of tube portions that penetrate a plurality of fins that are arranged in a direction that intersects the vertical height direction, and these plurality of tube portions and the plurality of fins are joined to each other via additional brazing portions.

6. A water heating system comprising the heat exchanger according to any one of claims 1 to 5.

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