JP2013079743A - Latent heat exchanger and water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a latent heat exchanger that has heat absorption pipes stably fixed in a casing.SOLUTION: A plurality of the heat absorption pipes 50 are arranged in a casing 2, and an elastic member 80 that presses the heat absorption pipes 50 by pressing and widening gaps of the heat absorption pipes 50 to make the heat absorption pipes 50 in a top stage and a bottom stage abut against a top plate 40 and a bottom wall 13, respectively, is arranged in the gaps of the heat absorption pipes 50 at the outermost periphery in a front-rear direction. Furthermore, the top plate 40 and the bottom wall 13 have upper projections 144 and lower projections 131 formed to project into the casing 2 when a casing body 10 and the top plate 40 are joined to each other.

Description

  The present invention relates to a latent heat exchanger that condenses water vapor in combustion exhaust and recovers latent heat, and a hot water supply apparatus having the latent heat exchanger.

  Conventionally, a so-called condensing type hot water supply apparatus having a sensible heat exchanger and a latent heat exchanger in a main body is known. In this type of water heater, after the sensible heat of the combustion exhaust is absorbed by the sensible heat exchanger, the latent heat of the combustion exhaust is further absorbed by the latent heat exchanger.

  As the latent heat exchanger, in order to reduce the size and increase the thermal efficiency, for example, as shown in FIG. 15, a linear portion and an arcuate folded portion are continuously repeated in a casing 801 through which combustion exhaust flows. A plurality of endothermic pipes 803 having a piping structure are arranged in a spiral state, and in order to circulate a heated fluid through each endothermic pipe 803, each of the inflow header 860 and the outflow header 870 provided on one side wall 802 of the casing 801 is provided respectively. A device in which the upstream end and the downstream end of the heat absorption pipe 803 are connected is known (for example, Patent Document 1).

  By the way, in this type of latent heat exchanger, the heat absorption pipe 803 vibrates when combustion exhaust gas is introduced into the casing 801 or when a fluid to be heated flows through the heat absorption pipe 803. It is necessary to fix 803. For this reason, for example, in Patent Document 1, a support body 806 including a spacer S obtained by bending a wire, and a main body portion 806a and an auxiliary portion 806b for fixing the entire heat absorbing tube 803 as shown in FIG. The use of is proposed.

JP 2008-151474 A

  However, in the above-mentioned Patent Document 1, all the endothermic tubes 803 must be inserted between the spacers S at a plurality of locations, and the support member 806 needs to be attached to a bundle of many endothermic tubes 803. This is very complicated and increases costs. Further, when the casing 801 and the heat absorption tube 803 are fixed by brazing, the heat absorption tube 803 is easily deformed by heat. As a result, the height and width of the endothermic tube 803 may be smaller than those of the support 806, and even if the support 806 is used, a gap is generated between the endothermic tube 803 and the support 806, and the endothermic There is a possibility that vibration of the tube 803 cannot be suppressed.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide latent heat heat in which a heat absorption tube is stably fixed in a casing in a latent heat exchanger that is required to be downsized and have high thermal efficiency. An object of the present invention is to provide an exchanger at low cost and to provide a hot water supply device using the latent heat exchanger.

According to the present invention, a casing having a combustion exhaust passage therein, a plurality of heat absorption tubes accommodated in the casing, an inflow header for introducing a fluid to be heated into each heat absorption tube, and each heat absorption tube A latent heat exchanger comprising an outflow header for deriving a fluid to be heated;
The casing has a box-shaped casing body having an upper opening, and a top plate for closing the upper opening of the casing body.
The casing body includes a rear wall, a front wall, a bottom wall having a drain outlet, an upstream end insertion hole through which the upstream end of the heat absorption pipe is inserted, and a downstream end insertion through which the downstream end of the heat absorption pipe is inserted. One side wall having a hole and the other side wall,
Each of the endothermic tubes has a piping structure in which the straight portion and the arcuate folded portion are repeated continuously in the casing,
The plurality of heat absorption tubes are arranged such that at least the arcuate folded portion overlaps between the top plate and the bottom wall,
An elastic member having an elastic force in the vertical direction is disposed in the outermost peripheral gap of at least one of the plurality of heat absorption tubes in the front-rear direction,
The elastic member presses the endothermic tube so that the gap between the endothermic tubes is widened, and at least a part of the uppermost and lowermost endothermic tubes contact the top plate and the bottom wall, respectively. A latent heat exchanger is provided.

  When a plurality of heat absorption tubes are stacked between the top plate and the bottom wall as described above, vibration and deformation of the heat absorption tubes are likely to occur. Further, when the upstream end and the downstream end of the endothermic tube are inserted into one side wall of the casing body, the other end side wall of the endothermic tube is not fixed to the casing, so that the endothermic tube is likely to vibrate. Further, when fixing the heat absorption tube in the casing by brazing, the heat absorption tube is easily deformed by heat, so that the heat absorption tube is in contact with the top plate and the bottom wall, respectively. Even if the casing is designed, a gap may be generated between them. However, according to the latent heat exchanger, an elastic member having an elastic force in the vertical direction is disposed in at least one outermost gap in the front-rear direction of the plurality of heat absorption tubes. The gap between the heat absorption tubes in the vertical direction is pushed wide, whereby at least a part of the uppermost and lowermost heat absorption tubes can be brought into contact with the top plate and the bottom wall, respectively. Thereby, the endothermic tube can be stably fixed in the casing.

Preferably, in the latent heat exchanger,
As the elastic member, a clip-like elastic member including an upper and lower elastic piece portion having an elastic force in the vertical direction and a connecting portion for connecting the upper and lower elastic piece portions is used.

  According to the latent heat exchanger, the heat absorption tube can be easily fixed by the clip-like elastic member having the upper and lower elastic pieces having elastic force. As a result, even if the endothermic tube is deformed in the brazing process, the endothermic tube can be stably fixed in the casing after the brazing process.

Preferably, in the latent heat exchanger,
Each of the top plate and the bottom wall has an upper protrusion and a lower protrusion that protrude toward the inside of the casing.

  According to the latent heat exchanger, the top plate and the bottom wall have the upper protrusion and the lower protrusion that protrude toward the inside of the casing, respectively. It can be made to contact | abut reliably by a board and a bottom wall.

  And according to this invention, the hot-water supply apparatus which has a latent-heat exchanger as described above is provided.

  As described above, according to the present invention, since the elastic member having the elastic force in the vertical direction is disposed in the outermost peripheral gap of the heat sink tube in the front-rear direction, at least the uppermost and lowermost heat sink tubes are arranged. A part can be reliably brought into contact with the top plate and the bottom wall, respectively. Thereby, the latent heat exchanger in which the heat absorption tube is stably fixed in the casing can be provided at a low cost.

FIG. 1 is a schematic perspective view showing an example of a latent heat exchanger according to Embodiment 1 of the present invention. FIG. 2 is a schematic exploded perspective view of FIG. FIG. 3 is a partial schematic cross-sectional view showing an internal structure in the left-right direction on the other side wall side of the latent heat exchanger according to Embodiment 1 of the present invention. FIG. 4 is a schematic perspective view showing a side rectifying plate according to Embodiment 1 of the present invention. FIG. 5 is a schematic perspective view showing the heat absorption tube according to Embodiment 1 of the present invention. FIG. 6 is a schematic cross-sectional view showing an arcuate folded portion of the heat absorption tube according to Embodiment 1 of the present invention. FIG. 7 is a schematic cross-sectional view showing a straight portion of the heat absorption tube according to Embodiment 1 of the present invention. FIG. 8 is a schematic cross-sectional view showing an internal structure in the front-rear direction of the latent heat exchanger according to Embodiment 1 of the present invention. FIG. 9 is a schematic perspective view showing an example of the elastic member according to Embodiment 1 of the present invention. FIG. 10 is a schematic cross-sectional view showing a cut surface taken along the line AA of FIG. FIG. 11 is a partial schematic cross-sectional view illustrating a process of joining the casing body and the top plate according to Embodiment 1 of the present invention by caulking, and FIG. 11 (A) shows a state before joining, and FIG. 11 (B). Indicates after bonding. FIG. 12 is a schematic configuration diagram illustrating an example of a hot water supply apparatus according to Embodiment 1 of the present invention. FIG. 13 is a schematic perspective view showing an example of a latent heat exchanger according to Embodiment 2 of the present invention. FIG. 14 is a schematic configuration diagram illustrating an example of a hot water supply apparatus according to Embodiment 2 of the present invention. FIG. 15 is a schematic plan sectional view showing an embodiment of a conventional latent heat exchanger. FIG. 16 is a schematic perspective view showing the support of FIG.

(Embodiment 1)
Hereinafter, the latent heat exchanger of the present embodiment and the hot water supply apparatus having the latent heat exchanger will be specifically described.

  1 is a schematic perspective view showing an example of a latent heat exchanger according to Embodiment 1 of the present invention, and FIG. 2 is a schematic exploded perspective view of FIG.

  As shown in FIGS. 1 and 2, the casing 2 of the latent heat exchanger 1 according to the present embodiment includes a box-shaped casing body 10 having an upper opening 16 and the upper opening 16 of the casing body 10 closed. And the top plate 40 to be used. Each of the casing body 10 and the top plate 40 is formed of a metal plate having corrosion resistance such as stainless steel.

  The casing body 10 has a back wall 11, a front wall 12, a bottom wall 13, one side wall 14, and the other side wall 15, and a box having an upper opening 16 by drawing a single metal plate. Are integrally molded. This will be described in more detail. The back wall 11 and the front wall 12 are erected from the front and rear side edges of the flat bottom wall 13 extending in a certain direction, and these are connected together via a corner portion. One side wall 14 and the other side wall 15 are erected from both left and right edge portions of the wall 13, and these are integrally connected via a corner portion. Furthermore, the left and right side edge portions of the back wall 11 and the front wall 12 are integrally connected to the one side wall 14 and the other side wall 15 via a corner portion, respectively. As a result, an inner space having an upper opening 16 surrounded by the rear wall 11, the front wall 12, the bottom wall 13, and the side walls 14 and 15 is formed in the casing body 10. Moreover, in this Embodiment, the top plate 40 is mounted in the open end of the back wall 11, the front wall 12, and both side walls 14, 15 when the casing main body 10 and the top plate 40 are joined by caulking. The mounting portion 101 in which the constituent walls 11, 12, 14, 15 are bent horizontally, and the upper flange portion bent upward from the mounting portion 101 for caulking the top plate 40 by caulking. 102 is continuously provided.

  The casing body 10 does not have to be formed by drawing all the constituent walls 11, 12, 13, 14, 15 as described above, and is formed by joining constituent walls of separate members by welding or brazing. May be. However, if the casing body 10 is formed by drawing a single metal plate as described above, it is not necessary to perform a welding operation or a brazing operation when manufacturing the casing body 10. In addition, since a joint portion by welding or brazing is not formed below the casing 2 having the casing body 10, even if drain is generated, retention of the drain below the casing 2 can be reduced. Furthermore, if the back wall 11, the front wall 12, the bottom wall 13, the one side wall 14, and the other side wall 15 are integrally formed by drawing, the casing 2 can be easily manufactured with a small number of parts.

  When the latent heat exchanger 1 is attached to the appliance main body of the hot water supply device, the exhaust inlet 111 into which the combustion exhaust gas is introduced and the combustion exhaust gas are led out at the upper, lower, left and right substantially central portions of the back wall 11 and the front wall 12, respectively. The exhaust outlet 121 is formed in a horizontally long rectangular shape. As a result, a combustion exhaust passage is formed in the casing 2 to communicate the exhaust outlet 121 to the exhaust outlet 121. In addition, the shape and opening location of the exhaust inlet 111 and the exhaust outlet 121 may be appropriately changed according to the usage pattern. For example, the exhaust inlet 111 may be formed in the bottom wall 13 and the exhaust outlet 121 may be formed in the top plate 40 according to the usage pattern of the hot water supply device.

  The bottom wall 13 is inclined downward from the back wall 11 side toward the front wall 12 side in order to smoothly drain the drain to the outside of the casing 2 when the drain is generated, and the drain wall is located at the lowest position of the slope. A drain outlet 17 is provided for discharging water. The drain outlet 17 is connected to a neutralizer through a drain discharge pipe. Further, when the casing body 10 and the top plate 40 are joined to the bottom wall 13, the bottom wall 13 projects toward the inside of the casing 2 at both ends in the left-right direction (both ends on the one side wall 14 side and the other side wall 15 side). Lower protrusions 131 and 131 are formed by drawing. As will be described later, the lower protrusion 131 is provided at a position where it comes into contact with the arcuate folded portion 52 of the endothermic tube 50 located at the lowermost stage.

  On the other hand, the upstream end insertion hole 141 through which the upstream end 53 of the heat absorption tube 50 is inserted and the downstream end 54 of the heat absorption tube 50 are inserted into both ends of the side wall 14 in the front-rear direction (both ends on the back wall 11 side and the front wall 12 side). The downstream end insertion holes 142 are formed by burring as many as the number of the heat absorption tubes 50. In the present embodiment, the upstream end insertion holes 141 and the downstream end insertion holes 142 are each arranged in two rows and in a staggered manner. The number and arrangement of the insertion holes 141 and 142 are appropriately selected according to the number of the heat absorption tubes 50. The other side wall 15 is the same as the one side wall 14 except that the upstream end insertion hole 141 and the downstream end insertion hole 142 are not formed.

  The top plate 40 includes a flat top plate main body 41, an upright piece 42 in which the periphery of the top plate main body 41 is bent upward over the entire circumference, and the upright piece 42 is horizontally extended over the whole circumference. And a lower flange portion 43 folded back in the direction. Similar to the casing body 10, the top plate 40 is formed by drawing a single metal plate. The upright piece 42 is formed to have a size that fits in the inner periphery of the upper opening 16 surrounded by the back wall 11, the front wall 12, the one side wall 14, and the other side wall 15 of the casing body 10. The flange portion 43 is formed in a size to be placed on the placement portion 101. Further, when the casing body 10 and the top board 40 are joined to the top plate main body portion 41, both ends in the left-right direction (both ends on the one side wall 14 side and the other side wall 15 side) face toward the inside of the casing 2. The protruding upper protruding portions 144 and 144 are formed by drawing. As will be described later, the upper protruding portion 144 is provided at a position where the upper protruding portion 144 abuts on the arcuate folded portion 52 of the heat absorption tube 50 located at the uppermost stage.

  As shown in FIGS. 3 and 4, when the casing body 10 and the top plate 40 are joined to the lower surface on the other side wall 15 side of the top plate 40, the top plate 40 extends in the combustion exhaust passage direction in the casing 2. The upper ends of the flat side rectifying plates 45 are joined by welding. That is, in the latent heat exchanger 1 of the present embodiment, since the casing body 10 integrally formed by drawing is used, the heat sink pipe 50 and the inflow header 60 and the outflow header 70 disposed outside the one side wall 14 In order to connect the two, it is necessary to lead out the upstream end 53 and the downstream end 54 of the heat absorption pipe 50 from the one side wall 14. Therefore, when the upstream end 53 and the downstream end 54 of the heat absorption pipe 50 are respectively inserted into the upstream end insertion hole 141 and the downstream end insertion hole 142 of the one side wall 14, the end of the arcuate folded portion 52 on the other side wall 15 side A space of a certain size is generated between the other side wall 15 and the inner surface. As a result, the combustion exhaust gas introduced from the exhaust inlet 111 flows into the space with less resistance, and the combustion exhaust gas does not efficiently contact the heat absorption pipe 50, which may reduce the thermal efficiency. However, if the side rectifying plate 45 is provided in the space between the end of the arcuate folded portion 52 on the side of the other side wall 15 and the inner surface of the other side wall 15 as described above, the side rectifying plate 45 causes combustion exhaust to be discharged. Since it flows to the endothermic tube 50 side, the combustion exhaust easily comes into contact with the endothermic tube 50, and the thermal efficiency can be improved. If the upper end of the side rectifying plate 45 is joined to the lower surface of the top plate 40, the casing 2 can be simply closed by closing the upper opening 16 of the casing body 10 with the top plate 40 to which the side rectifying plate 45 is joined. Can be assembled.

  Further, as shown in FIG. 4, the side rectifying plate 45 of the present embodiment includes a flat plate portion 451 having a joint portion 450 for joining the lower surface of the top plate 40 at the upper end, the exhaust inlet 111 side, and the exhaust outlet. It is formed from inclined surfaces 452 and 452 which are inclined so as to be bent from both ends on the 121 side toward the endothermic tube 50 side. Thereby, the combustion exhaust introduced into the casing 2 from the exhaust inlet 111 flows along the inclined surfaces 452 and 452 on the exhaust inlet 111 side and the exhaust outlet 121 side, so that the combustion exhaust easily comes into contact with the heat absorption pipe 50, Furthermore, thermal efficiency can be improved. The inclined surfaces 452 and 452 may be formed in a linear shape.

  Further, as shown in FIG. 3, the side rectifying plate 45 is provided such that the lower end thereof does not contact the bottom wall 13. If the side rectifying plate 45 extends so as to contact the bottom wall 13, the vibration of the side rectifying plate 45 is transmitted to both the top plate 40 and the bottom wall 13 when the combustion exhaust gas passes through the casing 2. And is prone to noise. However, if the side rectifying plate 45 is in contact with only the lower surface of the top plate 40 and is not in contact with the bottom wall 13, such noise can be prevented. Further, the drain flow is not obstructed, and the drain can be discharged smoothly, and since no joint is formed between the bottom wall 13 and the side rectifying plate 45, there is no need to worry about crevice corrosion due to the drain.

  Returning to FIG. 2, the top plate 40 is joined with an upper rectifying plate 46 that is inclined downward from the lower surface of the top plate 40 on the front wall 12 side toward the entire upper edge of the opening of the exhaust outlet 121. As a result, the combustion exhaust introduced from the exhaust inlet 111 is pressed down toward the endothermic tube 50 from above, making it easier for the combustion exhaust to come into contact with the endothermic tube 50, and the combustion exhaust on the exhaust outlet 121 side to It becomes easy to discharge | emit smoothly from the exhaust outlet 121 along.

  In the casing 2, a plurality of heat absorption pipes 50 (five in the present embodiment) through which tap water as a fluid to be heated flows are accommodated in a meandering state with a gap enough to allow combustion exhaust to pass through. . The upstream end 53 and the downstream end 54 of each endothermic tube 50 are respectively led out of the one side wall 14 from the upstream end insertion hole 141 and the downstream end insertion hole 142 of the one side wall 14 described above.

  FIG. 5 is a schematic perspective view showing one of the plurality of heat absorption tubes 50. The endothermic tube 50 of the present embodiment is bent at a plurality of locations on a corrugated tube (a tube having an outer surface shape in which valleys and peaks are alternately continuous in the axial direction) made of a metal having corrosion resistance such as stainless steel. And has a piping structure in which the straight portion 51 and the arcuate folded portion 52 are continuously repeated, and has a waveform shape in which the straight portion 51 and the arcuate folded portion 52 meander in one plane. However, in FIG. 1, FIG. 2, etc., in order to avoid complication, only a part of the straight part 51 is represented by a corrugated tube. Each endothermic tube 50 has a straight portion 51 extending in the left-right direction between the one side wall 14 and the other side wall 15, and an arcuate folded portion at both ends in the left-right direction (both ends on the one side wall 14 side and the other side wall 15 side). It is accommodated in the casing 2 so that 52 is located. Note that a plurality of heat absorption tubes 50 in which the straight portions 51 and the arcuate folded portions 52 bent in one direction are connected may be used, and these heat absorption tubes 50 may be arranged in the casing 2 in a spiral state.

  As shown in FIGS. 5 and 6, the arcuate folded portion 52 of the endothermic tube 50 has a flat cross-sectional shape that is flattened in the direction in which the endothermic tubes 50 are overlapped. FIG. 6 shows a shape obtained by cutting the valley portion of the endothermic tube 50. On the other hand, as shown in FIG. 7, the trough portion of the straight portion 51 of the endothermic tube 50 has a circular cross section.

  As shown in FIG.2 and FIG.3, each heat absorption pipe | tube 50 is piled up by the circular arc-shaped folding | returning part 52 processed into flat. As a result, the distance between adjacent heat absorption tubes 50 can be reduced in the direction in which the heat absorption tubes 50 are overlapped, the heat absorption tubes 50 are densely arranged, the latent heat exchanger 1 can be downsized, and combustion exhaust can be reduced. The heat absorption tube 50 can make contact efficiently. In order to fix the heat sink tube 50 in the casing 2, the uppermost and lowermost heat sink tubes 50 are in contact with the top plate 40 and the bottom wall 13, respectively, in a state where a plurality of the heat sink tubes 50 are stacked. In addition, each endothermic tube 50 is arranged.

  Further, the heat absorption tubes 50 to be overlapped are shifted by a half pitch in the wavelength direction of the waveform to be bent. That is, in FIG. 2, the endothermic pipes 50 adjacent to the second stage from the top and the second stage from the bottom are shifted by a half pitch in the upstream direction of the combustion exhaust (on the exhaust inlet 111 side). Is provided.

  As shown in FIG. 1 to FIG. 3 and FIG. 8 to FIG. 9, the gap between the outermost periphery in the front-rear direction of the heat absorption pipe 50 (the heat absorption pipe 50 facing the exhaust inlet 111 and the exhaust outlet 121) A clip-like elastic member 80 made of a corrosive metal is disposed.

  As often shown in FIG. 9, the clip-shaped elastic member 80 includes upper and lower elastic pieces 81 and 81 having an elastic force in the vertical direction, and a connecting portion 82 that connects the elastic pieces 81 and 81. have. The elastic pieces 81 and 81 are formed so as to have a symmetrical structure in the vertical direction, and each elastic piece 81 has a substantially semicircular fitting portion 83 that matches the outer shape of the heat absorbing tube 50 on the outer side. It has a curved corrugated shape to be formed. Further, in the state before the clip-like elastic member 80 is attached to the gap between the heat absorption tubes 50, the separation distance between the upper and lower fitting portions 83, 83 is formed wider than that of the heat absorption tubes 50, 50 adjacent in the vertical direction. Has been. Therefore, when the elastic piece portion 81 of the clip-shaped elastic member 80 is inserted into the gap between the heat absorption tubes 50, the heat absorption tube 50 adjacent to the clip-shaped elastic member 80 in a state where the heat absorption tube 50 is fitted in the fitting portion 83. , 50. The endothermic tube 50 on the other side wall 15 side is not fixed to the casing body 10, and the distance between the upper and lower fitting portions 83, 83 is formed wider than that of the adjacent endothermic tubes 50, 50. Therefore, the endothermic tube 50 is pressed by the elastic force of the elastic piece portion 81 so that the gap between the endothermic tubes 50 adjacent in the vertical direction is expanded. As a result, the height in the vertical direction of the plurality of stacked heat sink tubes 50 is increased, and the heat sink tubes 50 are deformed between the heat sink tubes 50 and the top plate 40 and the bottom wall 13 in the brazing process. Even if there is a gap, at least a part of the uppermost and lowermost heat sink tubes 50 can be brought into contact with the top plate 40 and the bottom wall 13, and the heat sink tubes 50 can be stably fixed in the casing 2. it can.

  As shown in FIG. 8, the clip-like elastic member 80 is disposed in the gap between the outermost endothermic tubes 50 in both the front and rear directions. The clip-like elastic member 80 only needs to be disposed in the gap between the outermost endothermic tubes 50 in the front-rear direction, but is disposed in the gap between the outermost endothermic tubes 50 in the front-rear direction. Thus, the heat absorption tube 50 can be fixed more stably. The number of clip-like elastic members 80 used in the gap between the outermost endothermic tubes 50 in the front-rear direction is not particularly limited, and a plurality of clip-like elastic members 80 may be used. The arrangement position of the clip-shaped elastic member 80 in the left-right direction is not particularly limited, but is preferably arranged on the side of the other side wall 15 that is the non-fixed end rather than the side of the one side wall 14 that is the fixed end. Further, in the present embodiment, the clip-like elastic member 80 is disposed in the gap between the heat absorption tubes 50 adjacent in the vertical direction, but the heat absorption tubes 50 (for example, the uppermost and lowermost heat absorption tubes) separated in the vertical direction. A clip-like elastic member 80 may be disposed in the gap between the tubes 50).

  In the present embodiment, the flattened arcuate folded portion 52 of the uppermost heat absorption tube 50 and the lowermost heat absorption tube 50 located at both ends in the left-right direction (both ends on the one side wall 14 side and the other side wall 15 side). The flattened arcuate folded portions 52 abut on the upper projecting portion 144 provided on the top plate 40 and the lower projecting portion 131 provided on the bottom wall 13, respectively. Thus, by forming the upper protruding portion 144 and the lower protruding portion 131 protruding into the casing 2, the uppermost and lowermost heat absorption tubes 50 are easily brought into contact with the top plate 40 and the bottom wall 13. The endothermic tube 50 can be more stably fixed inside. Further, since the flattened arcuate folded portion 52 is in contact with the upper and lower projecting portions 144 and 131, vibration of the heat absorption tube 50 due to a water hammer phenomenon or the like can be further suppressed.

  As described above, the upstream end 53 and the downstream end 54 of the heat absorption pipe 50 pass through the upstream end insertion hole 141 and the downstream end insertion hole 142 formed in the one side wall 14 of the casing body 10, respectively. As shown in FIG. 1, the upstream end 53 and the downstream end 54 are connected to an inflow header 60 and an outflow header 70 arranged outside the side wall 14, respectively. Thus, the upstream end 53 and the downstream end 54 of each heat absorption pipe 50 are connected to the inflow header 60 and the outflow header 70, respectively, and connected in parallel as a whole, whereby the heat absorption pipe 50 is connected in series. Compared to, water resistance is reduced.

  The inflow header 60 and the outflow header 70 to which the upstream end 53 and the downstream end 54 of the heat absorption pipe 50 are respectively connected are disposed outside the one side wall 14 of the casing body 10.

  As shown in FIG. 10, FIG. 2, and FIG. 10 showing the cut surface of the AA line of FIG. 1, these two headers 60 and 70 are composed of vessel-shaped header bodies 61 and 71 and header bodies 61 and 71, respectively. And are fitted by brazing so that the header bodies 61 and 71 and the opening portions of the header lid bodies 64 and 74 are opposed to each other. Is formed. Note that the outflow header 70 of the present embodiment has the same configuration as the inflow header 60 except that a header lid 74 is used in which the header lid 64 of the inflow header 60 is turned upside down. For this reason, in the following, the inflow header 60 will be mainly described as an example.

  As often shown in FIG. 10, the header main body 61 is fitted with the main body bottom plate 62 in which the connection hole 160 to which the upstream end 53 of the heat absorption pipe 50 is connected, the header main body 61 and the header lid 64. When assembled, the main body bottom plate 62 has a main body peripheral wall 63 that stands from the periphery of the main body bottom plate 62 toward the header cover body 64 and opens to the header cover body 64 side.

  The main body peripheral wall 63 of the header main body 61 is such that at least a part of the main body open end 630 is higher than the outer peripheral surface of the cover bottom plate 65 in the cross-sectional direction when the header cover 64 is fitted to the header main body 61. It is extended to. Further, as shown in FIG. 2, the main body peripheral wall 63 of the header main body 61 is formed in a substantially rectangular shape having a pair of long side portions 63a and a pair of short side portions 63b. Furthermore, as shown in FIG. 10, the main body open ends 630 of the long side portion 63a and the short side portion 63b are formed so as to spread outward. Thereby, when brazing the header main body 61 and the header lid body 64, a brazing reservoir M is formed between the inner surface of the main body peripheral wall 63 and the outer surface of the lid peripheral wall 66. As a result, not only can the joint area to be brazed between the inner surface of the main body peripheral wall 63 and the outer surface of the cover peripheral wall 66 be increased, but also the brazing material spreads in the brazing pool portion M, so Compared to the case where the brazing material is applied only to the end face, it is possible to prevent the brazing material from adhering to unnecessary portions in the brazing process.

  Further, when the header main body 61 and the header lid 64 are fitted to the main body open ends 630 of the opposing long side portions 63a of the header main body 61 of the present embodiment, they are bent toward the header lid 64. Claw portions 67, 67 to be formed are formed. These claw portions 67 and 67 are formed so as not to overlap in the direction of the short side portion 63b. By providing a claw portion 67 that is bent toward the header lid 64 at the main body open end 630 of the main body peripheral wall 63 as described above, after the header lid 64 is fitted to the header body 61, the outer circumference of the header lid 64 is The claw portion 67 abutting on the surface suppresses the movement of the header lid body 64, and the header lid body 64 is reliably prevented from being displaced. Further, if the claw portion 67 is formed at the main body open end 630 of the long side portion 63a, the header lid body 64 can be fixed to the header main body 61 while avoiding the inflow port 164 to which the water supply pipe is connected. The number of the claw portions 67 may be one or three or more depending on the size of the header body 61.

  The header lid body 64 joined to the header body 61 is directed from the periphery of the lid body bottom plate 65 toward the header body 61 when the lid body bottom plate 65 and the header body 61 and the header lid body 64 are fitted. It has a lid peripheral wall 66 that stands and opens to the header body 61 side. Like the main body peripheral wall 63 of the header main body 61, the cover peripheral wall 66 has a pair of long side portions and a pair of short side portions so that the outer surface of the cover peripheral wall 66 fits inside the inner surface of the main body peripheral wall 63. It has a substantially rectangular shape.

  As shown in FIG. 2, an inlet 164 and an outlet (not shown) are formed in the vicinity of the upper end of the lid bottom plate 65 and in the vicinity of the lower end of the lid bottom plate 75 by burring. Joint pipes 68 and 78 for connecting a connection pipe connected to the upstream end of the water supply pipe or the pipe body of the sensible heat exchanger are attached to the inlet 164 or the outlet. As a result, the fluid to be heated flows from the inflow header 60 to the outflow header 70 via the plurality of heat absorption tubes 50, the water vapor in the combustion exhaust is condensed on the outer surface of the heat absorption tubes 50, and latent heat is recovered.

  Next, an example of a method for manufacturing the latent heat exchanger according to the present embodiment will be specifically described.

  In the production of the latent heat exchanger 1, first, the upstream end 53 and the downstream end 54 of each heat absorption pipe 50 are inserted into the upstream end insertion hole 141 and the downstream end insertion hole 142 of the one side wall 14 of the casing body 10 formed by drawing. And the upstream end 53 and the downstream end 54 of the heat absorption pipe 50 are led out from the side wall 14 by a predetermined length. Then, a brazing material (such as a paste-like nickel brazing material) is applied to the boundary between the outer surface of the derived heat absorption tube 50 and the upstream end insertion hole 141 and the downstream end insertion hole 142. Next, the upstream end 53 and the downstream end 54 of the derived heat absorption pipe 50 are respectively inserted into the connection holes 160 and 170 of the header bodies 61 and 71, and the outer surfaces of the upstream end 53 and the downstream end 54 and the connection holes 160 and 170 are connected. Apply brazing material to the boundary. Note that the brazing material may be applied to the inner surfaces of the upstream end insertion hole 141 and the downstream end insertion hole 142 of the one side wall 14 and the inner surfaces of the connection holes 160 and 170 of the header main bodies 61 and 71.

  Separately from the above, joint cylinders 68 and 78 are fitted into the inlet 164 and outlet of the header lids 64 and 74 in advance, and a brazing material is applied to the boundary to temporarily fix them. The header lids 64 and 74 are jigs provided on the body peripheral walls 63 and 73 of the header bodies 61 and 71 so that the openings of the header lid bodies 64 and 74 face the openings of the header bodies 61 and 71. It arrange | positions between the retainers P and P and a pushing jig | tool (not shown), and the header cover bodies 64 and 74 are press-fitted in the header main bodies 61 and 71 with a pushing jig. After the press-fitting, the claw portions 67 and 77 provided at the main body open ends 630 and 730 of the main body peripheral walls 63 and 73 are bent toward the header cover bodies 64 and 74, and the inner surfaces of the main body peripheral walls 63 and 73 and the cover body peripheral walls 66 and 76. A brazing material is applied to the brazing reservoir M formed between the outer surface of the brazing member and the outer surface of the brazing member. At this time, the claw portions 67 and 77 are bent toward the header lids 64 and 74, but the brazing material penetrates into the base portions of the claw portions 67 and 77 by the penetration force of the brazing material.

  Next, as shown in FIG. 11 (A), the casing body so that the lower flange portion 43 of the top plate 40 is placed on the placement portion 101 provided at the periphery of the upper opening 16 of the casing body 10. The top plate 40 is placed on the top 10. At this time, the upper projecting portion 144 provided on the top plate 40 and the lower projecting portion 131 provided on the bottom wall 13 abut on the arcuate folded portions 52 of the uppermost and lowermost heat absorption tubes 50, respectively. The side rectifying plate 45 provided on the lower surface of the top plate 40 on the other side wall 15 side is a space formed between the end of the arcuate folded portion 52 on the other side wall 15 side and the inner surface of the other side wall 15. The upper rectifying plate 46 provided on the lower surface of the top plate 40 on the front wall 12 side is disposed so as to be inclined downward from the lower surface of the top plate 40 toward the entire upper edge of the opening of the exhaust outlet 121. The

  Then, as shown in FIG. 11 (B), the upper flange portion 102 of the casing body 10 is bent and caulked to the lower flange portion 43 of the top plate 40, and the upper opening 16 of the casing body 10 is moved to the top plate. Block at 40. Thereby, the subassembly in which the heat absorption pipe 50, the inflow header 60, and the like are temporarily fixed is assembled. As described above, in this embodiment, the constituent walls 11, 12, 13, 14, and 15 of the casing body 10 are integrally formed by drawing a single metal plate, and the influence of the drain is small. Since only the upper opening 16 of the casing body 10 is closed by the top plate 40, it is excellent in corrosion resistance simply by joining the casing body 10 and the top plate 40 by caulking without performing welding or brazing. The casing 2 can be produced.

  Next, the subassembly is put into a heating furnace, and brazing is performed in the furnace. Thereby, each member is brazed at the place where the brazing material is applied. In addition, since the casing body 10 and the heat absorption tube 50 are heat-treated (solid solution treatment) during the brazing process, the residual stress generated in the casing body 10 by the deep drawing process and the residual stress in the arcuate folded portion 52 are removed. The occurrence of stress corrosion cracking can be prevented even when there is contact with a strongly acidic drain.

  After performing the brazing process as described above, the clip-like elastic member 80 is inserted into the gaps of the outermost endothermic pipe 50 in the front-rear direction from the exhaust inlet 111 and the exhaust outlet 121, and the endothermic pipe 50 is The clip-like elastic member 80 is locked between the heat absorption tubes 50 in a state of being fitted into the fitting portion 83 of the elastic piece portion 81. Thereby, even if a gap is generated between the uppermost endothermic tube 50 and the top plate 40 or between the lowermost endothermic tube 50 and the bottom wall 13 in the brazing process, The gap is widened so that the uppermost and lowermost endothermic tubes 50 can be brought into contact with the upper projecting portion 144 of the top plate 40 and the lower projecting portion 131 of the bottom wall 13, respectively. The fixed latent heat exchanger 1 can be produced.

  Next, an example of the hot water supply apparatus of the present embodiment will be specifically described.

  FIG. 12 is a schematic configuration diagram showing the hot water supply apparatus of the present embodiment. A sensible heat exchanger 3 and the latent heat exchanger 1 are provided in an instrument main body (not shown).

  As shown in FIG. 12, the sensible heat exchanger 3 is disposed below the latent heat exchanger 1. A gas burner 4 for burning the gas supplied from the gas supply pipe is disposed below the sensible heat exchanger 3, and further, combustion air is blown to the gas burner 4 below the gas burner 4. A blower fan 5 is provided.

  The sensible heat exchanger 3 includes a large number of fin groups 332 arranged in parallel and a meandering tube body 331 penetrating the fin groups 332. The sensible heat exchanger 3 and the latent heat exchanger 1 are divided vertically by a bottom wall 13 of the casing body 10 of the latent heat exchanger 1.

  The sensible heat exchanger 3 and the latent heat exchanger 1 communicate with each other via the exhaust inlet 111 described above, and are sent from the sensible heat exchanger 3 to the latent heat exchanger 1 through the exhaust inlet 111. The produced combustion exhaust gas passes through the latent heat exchanger 1 and is then discharged from the exhaust outlet 121 to the outside of the instrument body.

  In the hot water supply apparatus of the present embodiment, combustion exhaust is generated by combustion of the gas burner 4, the sensible heat exchanger 3 and the latent heat exchanger 1 are heated by this combustion exhaust, and the combustion is performed by the sensible heat exchanger 3. The sensible heat of the exhaust is absorbed and the latent heat is absorbed from the combustion exhaust after the sensible heat is absorbed by the latent heat exchanger 1. At this time, the combustion exhaust gas introduced into the casing 2 and the heated fluid flowing in the endothermic tube 50 vibrate the endothermic tube 50, but the latent heat exchanger 1 according to the present embodiment includes the endothermic tube 50 in the casing 2. Is stably fixed, it is possible to suppress vibration of the heat absorption pipe 50 during operation of the hot water supply apparatus. Further, when the water vapor in the combustion exhaust gas is cooled below the dew point and the contained water vapor is condensed, strongly acidic drain is generated in the latent heat exchanger 1, and the drain generated in the latent heat exchanger 1 is the casing. It drops on the bottom wall 13 of the main body 10. However, as described above, the latent heat exchanger 1 according to the present embodiment has the casing body 10 in which the constituent walls 11, 12, 13, 14, and 15 are integrally formed by drawing, so that the lower part of the casing 2. No joints are formed by welding or brazing, and therefore, the accumulation of drain is reduced below the casing 2, and the drain is smoothly discharged from the drain outlet 17 provided in the bottom wall 13 to the neutralizer. Can be made. As a result, corrosion of the casing 2 due to drain can be suppressed, and a hot water supply device having high durability can be obtained.

  The joint cylinder 68 of the inflow header 60 is connected to a water supply pipe that guides cold water from a water supply source such as a water pipe, and the joint cylinder 78 of the outflow header 70 is connected to the upstream end of the pipe body 331 of the sensible heat exchanger 3. It is connected to a connecting pipe that communicates with Accordingly, the cold water from the water supply pipe is heated while passing through the latent heat exchanger 1 and the sensible heat exchanger 3 to become hot water, and the hot water is connected to the downstream end of the tube body 331 of the sensible heat exchanger 3. The hot water pipes are sent to hot water terminals such as bathrooms and kitchens.

(Embodiment 2)
In the first embodiment, the latent heat exchanger used in the hot water supply apparatus having one heating circuit has been described. However, in the present embodiment, the latent heat exchanger used in the hot water supply apparatus having two heating circuits is described. To do. In addition, about the structure similar to the latent heat exchanger and hot water supply apparatus in Embodiment 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  FIG. 13 is a schematic perspective view of the latent heat exchanger 1a of the present embodiment as viewed from the back side.

  As shown in the figure, the casing of the latent heat exchanger 1a has a casing body 10 and a top plate 40 that closes the upper opening of the casing body 10 as in the first embodiment. Is defined by a partition wall W into a first region on the one side wall 14 side and a second region on the other side wall 15 side, and the first endothermic tube 50a and the second endothermic tube are arranged in each region parallel in the left-right direction. 50b is accommodated. The configurations of the first and second heat absorption tubes 50a and 50b and the clip-like elastic member 80 for fixing the first and second heat absorption tubes 50a and 50b are the same as those of the first embodiment. .

  As in the case of the first embodiment, the casing body 10 is formed by drawing a single metal plate to integrally form the back wall 11, the front wall 12, the bottom wall 13, the one side wall 14, and the other side wall 15. Yes. However, in the present embodiment, as in the first embodiment, the casing body 10 produced by welding or brazing the constituent walls 11, 12, 13, 14, 15 made of different members may be used. .

  Two exhaust inlets 111a and 111b are opened in the back wall 11 in order to introduce combustion exhaust into each of the first region and the second region. Further, as shown in FIG. 14, the front wall 12 has one exhaust outlet 121 communicating with the first and second regions. Like the rear wall 11, the front wall 12 has two exhaust outlets 121. An exhaust outlet may be provided. Furthermore, although not shown, the first side wall 14 has a first upstream end insertion hole and a first downstream end insertion hole through which the upstream end and the downstream end of the first heat absorption pipe 50a are inserted, respectively. The second side wall 15 is provided with a second upstream end insertion hole and a second downstream end insertion hole through which the upstream end and the downstream end of the second heat absorption pipe 50b are inserted. The bottom wall 13 is provided with a lower protruding portion 131 that comes into contact with the arcuate folded portions of the first and second endothermic pipes 50a and 50b, and a drain outlet 17 for discharging the drain. .

  Accordingly, also in the latent heat exchanger 1a of the present embodiment, the clip-like elastic member 80 and the first and second protrusions 144 and 131 are formed on the top plate 40 and the bottom wall 13 respectively. The endothermic tubes 50a and 50b can be stably fixed. Thereby, the vibration of the 1st and 2nd heat absorption pipe | tube 50a, 50b at the time of the action | operation of a hot-water supply apparatus can be suppressed. In addition, the casing body 10 does not have a welded or brazed joint, and it is not necessary to perform a welding operation or a brazing operation for assembling the casing body 10. In addition, since a joint portion by welding or brazing is not formed below the casing, even if drain is generated, retention of the drain below the casing can be reduced. Furthermore, since the back wall 11, the front wall 12, the bottom wall 13, the one side wall 14, and the other side wall 15 are integrally formed by drawing, a casing can be easily manufactured with a small number of parts. And since only the upper opening part of the casing main body 10 with little influence of drain is obstruct | occluded with the top plate 40, it only joins the casing main body 10 and the top plate 40 by caulking without performing welding or brazing. A casing having excellent corrosion resistance can be produced.

  The top plate 40 has the same configuration as that of the first embodiment, but the side rectifying plate 45 is provided only in the first region on the one side wall 14 side. In addition, although a side baffle plate can also be provided in the second region, for example, if the partition wall W is provided after the second heat absorption tube 50b is accommodated, the partition wall W is connected to the second heat absorption tube 50b. It can arrange | position close to the edge part of this circular arc-shaped folding | turning part. Therefore, in this embodiment, the side rectifying plate 45 may be provided in either the first region or the second region.

  A first inflow header 60 a and a first outflow header 70 a connected to the upstream end and the downstream end of the first heat absorption pipe 50 a are disposed outside the one side wall 14. A second inflow header 60b and a second outflow header 70b connected to the upstream end and the downstream end of the second heat absorption pipe 50b are disposed outside. Each of these headers has the same header body and header lid as in the first embodiment.

  FIG. 14 is a schematic configuration diagram showing an example of a hot water supply apparatus having the latent heat exchanger 1a.

  In this hot water supply apparatus, the combustion exhaust generated by the first gas burner 4a is sent to the first sensible heat exchanger 3a by the blower fan 5a to recover the sensible heat, and further the first heat of the latent heat exchanger 1a. The latent heat is recovered by being sent to the area. Similarly, the combustion exhaust generated by the second gas burner 4b is sent to the second sensible heat exchanger 3b by the blower fan 5b to recover the sensible heat, and further to the second region of the latent heat exchanger 1a. It is sent and latent heat is recovered. According to this hot water supply apparatus, for example, one heating circuit can be used for a hot water heating circuit, and the other heating circuit can be used for a heating heating circuit.

(Other embodiments)
In the above-described embodiment, the uppermost and lowermost endothermic tubes 50 and the top plate 40 and the bottom wall 13 are in direct contact with each other, but if the entire endothermic tube 50 can be fixed in the casing 2, for example, You may contact | abut indirectly through another buffer member.

DESCRIPTION OF SYMBOLS 1 Latent heat exchanger 2 Casing 10 Casing main body 11 Back wall 12 Front wall 13 Bottom wall 14 One side wall 15 The other side wall 16 Upper opening part 17 Drain drain port 40 Top plate 50 Heat absorption pipe 51 Straight part 52 Arc-shaped folding part 60, 60a , 60b Inflow header 70, 70a, 70b Outflow header 80 Clip-like elastic member 81 Elastic piece portion 82 Connection portion 111 Exhaust inlet 121 Exhaust outlet 131 Lower protrusion 141 141 Upstream end insertion hole 142 Downstream end insertion hole 144 Upper protrusion

Claims (4)

A casing having a passage for combustion exhaust therein, a plurality of heat absorption tubes accommodated in the casing, an inflow header for introducing a fluid to be heated into each heat absorption tube, and a fluid to be heated from each heat absorption tube A latent heat exchanger with an outflow header,
The casing has a box-shaped casing body having an upper opening, and a top plate for closing the upper opening of the casing body.
The casing body includes a rear wall, a front wall, a bottom wall having a drain outlet, an upstream end insertion hole through which the upstream end of the heat absorption pipe is inserted, and a downstream end insertion through which the downstream end of the heat absorption pipe is inserted. One side wall having a hole and the other side wall,
Each of the endothermic tubes has a piping structure in which the straight portion and the arcuate folded portion are repeated continuously in the casing,
The plurality of heat absorption tubes are arranged such that at least the arcuate folded portion overlaps between the top plate and the bottom wall,
An elastic member having an elastic force in the vertical direction is disposed in the outermost peripheral gap of at least one of the plurality of heat absorption tubes in the front-rear direction,
The elastic member presses the endothermic tube so that the gap between the endothermic tubes is widened, and at least a part of the uppermost and lowermost endothermic tubes contact the top plate and the bottom wall, respectively. There is a latent heat exchanger. The latent heat exchanger according to claim 1,
The said elastic member is a latent heat heat exchanger which consists of a clip-shaped elastic member provided with the up-and-down elastic piece part which has an elastic force in an up-down direction, and the connection part which connects the said up-and-down elastic piece part. The latent heat exchanger according to claim 1 or 2,
The top plate and the bottom wall each have an upper protrusion and a lower protrusion that protrude toward the inside of the casing.   The hot water supply apparatus which has a latent-heat heat exchanger of any one of Claims 1-3.