JP2010085037A - Heat exchanger, water heater, and coil tube unit for heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat exchanger avoiding the generation of a large gap in an adjacent area of a plurality of coil tube units, and suppressing the reduction of a heat recovery amount from a heating medium caused by the gap. <P>SOLUTION: In the plurality of coil tube units U, double winding loop structures S, S' are provided at ends in the axial length direction of a coil tube body 3A, and the double winding loop structures S, S' have configurations wherein, one end of an additional loop 31 surrounding a terminal end loop positioned at an end of the axial length direction among a plurality of loops 30 of the coil tube body 3A is connected to the terminal end loop, and an extension tube body 4A is connected to the other end of the additional loop 31. In the additional loop 31, a vertical interval of an inclination in the axial length direction is smaller than the terminal end loop, or the loop is formed in a non-inclined shape not having inclination, and in the adjacent area of the coil tube units U, the additional loops 31 are adjacent to each other. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention comprises a heat exchanger that uses a plurality of coil tube units to constitute a heat transfer tube, and recovers heat from a heating medium such as combustion gas using the plurality of coil tube units, a hot water supply device including the heat exchanger, etc. And a coiled tube unit used as a component of the heat exchanger.

  An example of a conventional heat exchanger is described in Patent Document 1. In the heat exchanger described in the document, the heat transfer tubes are configured using a plurality of coil tube units, and the plurality of coil tube units are arranged in the axial direction in the casing. . Each coil tube unit has a spiral coil tube portion in which a plurality of loop portions are connected in series, and a pair of extended tube portions connected to both ends of the coil tube unit. It is possible to allow water to flow from the extended tube portion into the coil tube portion. On the other hand, when the combustion gas is supplied to the inner regions of the plurality of coil tube units, the combustion gas acts on the coiled tube portion while passing between the plurality of loop portions of the coil tube portion. . Therefore, it is possible to recover the heat from the combustion gas by the coiled tube portion and to heat the water flowing through the coil tube portion. If a heat transfer tube is configured using a plurality of coil tube units, the amount of heat recovered from the combustion gas can be changed as appropriate by increasing or decreasing the number of coil tube units, and the desired hot water heating capacity is exhibited. This makes it easier to design and manufacture the heat exchanger.

  However, the prior art has a problem to be solved as described below.

  That is, in the prior art, a coil tube unit 9 as shown in FIG. 15 is used. In this coil tube unit 9, a pair of extended tube portions 91 extend in the tangential direction from both ends of a spiral coil tube portion 90. A dimension L <b> 10 between the pair of extending tube portions 91 is as large as the inner diameter of the coil tube portion 90. Further, a step h is formed between the extended tube portion 91 and the surface portion of the coil tube portion 90 located in the vicinity thereof. For this reason, as shown in FIG. 16, when the plurality of coil tube units 9 are arranged in the axial length direction, a gap 92 having a width L10 is formed in a region where they are adjacent to each other. In this case, when the combustion gas is supplied to the inside of each coil tube portion 90, most of the combustion gas passes through the gap 92, and the combustion gas is effectively applied to each coil tube portion 90. This causes a problem that the amount of heat recovery is reduced. In the example shown in FIGS. 15 and 16, the thickness of each part of the coil tube part 90 is uniformly formed. However, in Patent Document 1, the thickness of each part of the coil tube part is shown. A configuration is shown in which the gaps 92 are not generated as described above. However, in such a configuration, compared with the case where the thickness of each part of the coiled tube body part is formed uniformly, the manufacturing operation of the coiled tube body part becomes considerably troublesome and the manufacturing cost becomes high.

JP-T-2006-503260

  The present invention has been conceived under the circumstances as described above, and avoids the generation of large gaps in adjacent regions between a plurality of coiled tube units, and heating due to the existence of the gaps. A heat exchanger capable of appropriately suppressing a decrease in the amount of heat recovered from the working medium, a hot water device provided with the heat exchanger, and a coil tube unit for a heat exchanger suitable as a component of the heat exchanger The issue is to provide.

  In order to solve the above-described problems, the present invention takes the following technical means.

The heat exchanger provided by the first aspect of the present invention includes a plurality of coil tube units arranged in the axial length direction, and each of the coil tube units includes a plurality of loop portions arranged in the axial length direction. A spiral coil tube body portion, and an extended tube body portion connected to the coil tube body portion and extending outward from the coil tube body portion. A heating medium that is capable of heating the fluid flowing through the coiled tube portion by passing a heating medium between the plurality of loop portions from one of the inner region and the outer region toward the other. In the exchanger, as the plurality of coil tube units, one in which a double-wound loop structure portion is provided at both ends or one end portion in the axial length direction of the coil tube body portion is used. The wound loop structure portion includes a plurality of loops of the coil tube portion. One end of an additional loop portion that surrounds the periphery of the loop portion at the end is connected to the end loop portion located at the end in the axial length direction of the loop portion, and the other end of the additional loop portion extends to the other end. In addition to having a configuration in which the tubular body portion is connected, the additional loop portion has a smaller height difference in inclination in the axial length direction than the terminal loop portion, or is non-inclined without inclination, In the adjacent region between the plurality of coil tube units, the additional loop portions of the double-winding loop structure portion are adjacent to each other.
In the present invention, among the plurality of loop parts of the coiled tube part, the loop part located at the end in the axial length direction is referred to as “terminal loop part”. No distinction is made between “the loop portion of” and “the loop portion of the starting end”, and both are “the loop portion of the end”.

  According to the configuration described above, in the adjacent region between the plurality of coil tube units, the additional loop portions of the double-wrapped loop structure portion are adjacent to each other. The additional loop portion has a small inclination difference in the axial length direction or is not inclined, so that there is no large gap between the additional loop portions adjacent to each other. It is also possible to appropriately eliminate the formation of a large step in the axial length direction between the loop portion and the extending tube portion. Further, since the periphery of the end loop portion is surrounded by the additional loop portion, there is a gap between the end loop portions, and even if the heating medium advances in this gap, The progress of the heating medium is appropriately blocked by the additional loop portion. For this reason, according to the present invention, it is possible to prevent a large gap from being formed in the adjacent region between the coil tube units, which causes a decrease in heat exchange efficiency, and to obtain high heat exchange efficiency. Further, in the present invention, unlike Patent Document 1, as a means for preventing large gaps from being formed in adjacent regions between the coil tube units, the thickness of each part of the coil tube body is formed non-uniformly. There is no need, and the manufacturing cost of the coil tube unit can be reduced.

  In a preferred embodiment of the present invention, each of the coil tube units includes first and second coil tube portions that are substantially concentrically wound, and the first coil tube portions are The second coil tube body portion includes a plurality of loop portions other than the additional loop portion of the first coil tube body portion. A plurality of loop portions that are enclosed and formed to have substantially the same winding diameter as the additional loop portion are provided.

  According to such a configuration, it is possible to recover heat from the heating medium using each of the first and second coil tube parts, and it is more preferable to increase the heat exchange efficiency. Further, according to the above-described configuration, the first and second loop portions of the second coil tube body portion do not protrude greatly outward than the additional loop portions of the first coil tube body portion. It can be set as the structure which combined the coil pipe | tube part of space efficiency efficiently.

  A hot water apparatus provided by the second aspect of the present invention includes a burner and a heat exchanger for performing heat recovery from the combustion gas generated by the burner to perform hot water heating. However, the heat exchanger provided by the first aspect of the present invention is used as the heat exchanger.

  According to such a configuration, the same effect as described for the heat exchanger provided by the first aspect of the present invention can be obtained.

  The coil tube unit for a heat exchanger provided by the third aspect of the present invention includes a spiral coil tube body portion having a plurality of loop portions arranged in the axial length direction, and is connected to the coil tube body portion. A coil tube unit for a heat exchanger comprising an extended tube portion extending outward of the coil tube portion, at both ends or one end portion in the axial length direction of the coil tube portion. Is provided with a double-wound loop structure portion, and the double-winding loop structure portion is a terminal loop portion located at an end portion in the axial length direction among the plurality of loop portions of the coil tube body portion. In addition, one end of the additional loop portion surrounding the periphery of the loop portion at the end is connected, and the extended tubular body portion is connected to the other end of the additional loop portion, and the additional loop portion is The slope in the axial length direction is higher than the end loop portion. It is characterized in that there is a small or no inclination untilted shape.

  According to such a configuration, it can be suitably used as a coil tube unit constituting the heat exchanger provided by the first aspect of the present invention.

  Other features and advantages of the present invention will become more apparent from the following description of embodiments of the present invention with reference to the accompanying drawings.

  Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

  1 to 14 show an example of a heat exchanger to which the present invention is applied, a hot water device provided with the heat exchanger, and a configuration related thereto. In the present embodiment, the vertical positional relationship of the constituent elements is as described in the drawings.

  As clearly shown in FIG. 1, the hot water device WH of the present embodiment includes a burner 1 and a heat exchanger HE. The burner 1 is, for example, a gas burner. A gas mixture of combustion air and fuel gas is supplied to the burner 1 using a fan (not shown), and this gas mixture is ignited by an ignition plug (not shown). Combustion is performed by operation. The burner 1 is disposed in a first space portion 7A described later of the heat exchanger HE.

  The heat exchanger HE includes a casing 2 and a plurality of coil tube units U (U1 to U3) as heat transfer tubes accommodated in the casing 2. The casing 2 has a peripheral wall portion 20 surrounding the periphery of the plurality of coiled tube units U, and at both ends in the horizontal direction, an insertion opening 21 for the burner 1 and a combustion gas discharge port 22 for which heat recovery has been completed. Is formed. In addition, a header portion 5 for allowing water to flow through the plurality of coil tube units U is provided at the lower portion of the peripheral wall portion 20.

  As shown in FIG. 3, the plurality of coil tube units U are arranged so as to approach each other in the axial length direction (the direction in which the central axis CL extends). In the hot water device WH of FIG. 1, the plurality of coil tube units U are arranged in a substantially horizontal direction, but for convenience, in FIG. Also in the drawings after FIG. 4, the coil tube unit U or its components are shown in a posture corresponding to FIG.

  As shown in FIGS. 4 to 8, each coil tube unit U has first and second coil tube portions 3 </ b> A and 3 </ b> B that are substantially concentrically wound, and these first and second coils. The extending tube portions 4A and 4B are connected to the tube portions 3A and 3B, respectively. As shown in FIGS. 9 to 11, the first coil tube portion 3 </ b> A has a portion in which a plurality of circular loop portions 30 whose winding diameters are arranged substantially the same are arranged at a constant pitch in the axial length direction. is doing. However, double winding loop structures S and S ′ are provided at both ends in the axial length direction of the first coil tube portion 3A (in the drawings after FIG. 4, both upper and lower ends of the coil tube portion 3A). ing.

  The double-wrapped loop structure portions S and S ′ have a terminal loop portion 30a positioned at an end portion (upper end portion or lower end portion) in the axial length direction among the plurality of loop portions 30 arranged in the axial length direction, One end of the additional loop portion 31 having a larger winding diameter than that of the loop portion 30a is connected, and these are portions that are formed into a lap winding shape. The extended tubular body portion 4 </ b> A is connected to the other end of the additional loop portion 31 and is bent so as to extend in the normal direction of the additional loop portion 31. The plurality of loop portions 30, the additional loop portion 31, and the extended tube portion 4A can be integrally formed by bending a single metal tube. Of course, it can also be set as the structure which those parts formed and connected with another member.

  The additional loop portion 31 surrounds the periphery of the terminal loop portion 30a. Further, the additional loop portion 31 is configured so as not to be inclined in the axial length direction except for a portion close to the terminal loop portion 30a. More specifically, in FIG. 11, each loop portion 30 is inclined by an appropriate angle θ1 with respect to the orthogonal line L1 of the central axis CL. On the other hand, the tube axis direction center line L2 in the substantially entire circumferential area of the additional loop portion 31 is substantially parallel to the orthogonal line L1 described above. Further, in the double-wrapped loop structure portion S, the upper surface 31 ′ of the additional loop portion 31 has a height equal to or equal to or higher than the uppermost surface 30a ′ of the terminal loop portion 30a. The portion does not protrude upward from the additional loop portion 31. The double-winding loop structure portion S ′ has a basic configuration in which the vertical positional relationship between the terminal loop portion 30a and the additional loop portion 31 is opposite to that of the double-winding loop structure portion S. Is the same as the double-wrapped loop structure S.

  As shown in FIGS. 8 and 12 to 14, the second coil tube body portion 3 </ b> B is configured not to include the above-described double winding loop structure portions S and S ′, and a plurality of loop portions 35 are provided. It is a spiral lined up in the axial direction. As shown in FIG. 12, among the loop portions 35 of the uppermost layer and the lowermost layer, the portion indicated by reference numeral n1 swells outward. This is because the extended tube portion 4B is disposed close to the other extended tube portion 4A along the portion n1 along the additional loop portion 31 of the first coil tube portion 3A.

  Each loop portion 35 of the second coiled tube portion 3B is not entirely inclined in the axial length direction, but only partially inclined in the axial length direction. More specifically, as shown in FIG. 14, a region of each loop portion 35 opposite to the extending tube portion 4B is not inclined with respect to the orthogonal line L1 of the central axis CL. On the other hand, the region on the extended tube portion 4B side is inclined at an appropriate angle θ2 with respect to the orthogonal line L1. The significance of this will be described later.

  As shown in FIGS. 4 to 7, the second coil tube portion 3B is arranged so as to surround the first coil tube portion 3A. However, preferably, as shown well in FIG. 7, the plurality of loop portions 30 and 35 are set to have a staggered arrangement. Further, the plurality of loop portions 35 have substantially the same winding diameter as that of the additional loop portion 31 and are disposed between the two additional loop portions 31. As described above, the additional loop portion 31 is substantially non-inclined in its entire area, whereas each loop portion 35 is connected to the extended tube portion 4B as described with reference to FIG. The region on the opposite side is not inclined. For this reason, about the non-inclined part of each loop part 35, it can arrange | position in the state substantially parallel to the two additional loop parts 31, and can arrange | position in order between them.

  As shown in FIG. 3, in a state where a plurality of coil tube units U1 to U3 are arranged, a double winding loop is provided in an adjacent region between the coil tube units U1 and U2 and an adjacent region between the coil tube units U2 and U3. The additional loop portions 31 of the structure portions S and S ′ are adjacent to each other. With such a configuration, a large gap is preferably avoided in the adjacent region.

  As shown in FIG. 1, the plurality of coil tube units U are arranged in the casing 2 in a state where they are arranged side by side so that their axial length directions are substantially horizontal directions. As positioning means for the plurality of coil tube units U, a set of spacers 29a, 29b and other members (not shown) that sandwich them in the horizontal direction are appropriately used. A partition member 28 is provided between the coil tube units U2 and U3, and an inner region of the coil tube units U1 to U3 includes a first space portion 7A in which the burner 1 is disposed, and combustion gas. The second space portion 7 </ b> B communicating with the discharge port 22 is partitioned. As a result, the two coil tube units U1, U2 serve as a first heat exchanging portion H1 surrounding the first space portion 7A, and the remaining coil tube units U3 define the second space portion 7B. It becomes the surrounding 2nd heat exchange part H2. When the burner 1 is driven to generate combustion gas in the first space portion 7A, the combustion gas passes between the loop portions 30 and between the loop portions 35 of the first heat exchange portion H1. To advance around the first heat exchange section H1. Strictly speaking, the combustion gas also passes between the loop portion 35 of the first heat exchanging portion H1 and the additional loop portion 31 (this is the same for the second heat exchanging portion H2 described below). is there). Thereafter, the combustion gas passes between the loop portions 35 of the second heat exchange portion H2 and between the loop portions 30 and flows into the second space portion 7B, and thereafter the casing is discharged from the exhaust port 22 through the casing. 2 is discharged to the outside. In such a process, sensible heat and latent heat are sequentially recovered from the combustion gas by the first and second heat exchanging units H1 and H2.

  As clearly shown in FIG. 2, the extending tube portions 4 </ b> A and 4 </ b> B of each coil tube unit U extend downward and are connected to the header portion 5. As shown in FIG. 1, the header part 5 has a water inlet 50 and a hot water outlet 51, and has a configuration in which a plurality of hot water inflow chambers 57 communicating with the extended pipe parts 4A and 4B are formed. Have. When water is supplied from the outside to the water inlet 50, the water flows through each coil tube unit U and is heated, and the hot water generated by heating is discharged from the hot water outlet 51 to the outside.

  When latent heat recovery is performed by the second heat exchange part H2, water vapor in the combustion gas is condensed, and drains (condensed water) are generated on the surfaces of the coil tube parts 3A and 3B of the second heat exchange part H2. Adhere to. On the other hand, as described above, the extended tube portions 4A and 4B extend downward from the coil tube portions 3A and 3B, so that the drain covers the surfaces of the extended tube portions 4A and 4B. It becomes easy to flow down. Preferably, the header portion 5 is configured to have a drain discharge port that receives a drain flowing from above and can discharge the drain to the outside of the header portion 5 and the casing 2.

  Next, the operation of the hot water device WH provided with the above-described heat exchanger HE will be described.

  First, when the burner 1 is driven to generate combustion gas in the first space portion 7A, as described above, this combustion gas flows between the loop portions 30 of the first heat exchange portion H1 and the loop. After passing between the parts 35 and proceeding around the first heat exchange part H1, the second heat exchange part H2 passes between the loop parts 35 and between the loop parts 30 and passes through the first heat exchange part H1. 2 flows into the space portion 7B, and is then discharged from the discharge port 22 to the outside of the casing 2. Each of the first and second heat exchanging parts H1 and H2 has a configuration in which the coil tube parts 3A and 3B are overlapped, and the plurality of loop parts 30 and 35 are in the flow direction of the combustion gas. Therefore, the amount of heat recovered from the combustion gas can be increased and high heat exchange efficiency can be obtained without using, for example, flat tubes as the coil tube portions 3A and 3B.

  In order to increase the heat recovery amount, it is desirable to have a configuration in which a large gap for allowing combustion gas to escape is not generated in the adjacent region between the coil tube units U. On the other hand, in the heat exchanger HE of the present embodiment, as described with reference to FIG. 3, in the adjacent region between the coil tube units U, additional loops of the double-loop structure portions S and S ′ are added. The portions 31 are adjacent to each other. Since the additional loop portion 31 is substantially non-inclined in the axial direction in the entire circumference, it is possible to prevent a large gap from being generated at a location where the additional loop portions 31 are adjacent to each other. In addition, as shown in FIG. 3, although a relatively large gap is generated in the portion where the loop portions 30a at the end of the first coil tube body portion 3A are adjacent to each other, the periphery of this gap is added. It is surrounded by the loop part 31 of. For this reason, there is no inconvenience that a large amount of combustion gas passes through the gap formed in the adjacent region between the coil tube units U, and the heat exchange efficiency of the heat exchanger HE can be further increased.

  The present invention is not limited to the contents of the above-described embodiment. The specific configuration of each part of the heat exchanger, the hot water device, and the coiled tube unit for the heat exchanger according to the present invention can be varied in design in various ways.

  For example, the tubular body constituting the coil tube unit is not limited to a tubular body having a circular cross section, and for example, a tubular body having an elliptical cross section or a flat tubular body similar to Patent Document 1 can be used. The specific cross-sectional shape is not limited. In addition, the coil tube unit may have either a configuration in which a plurality of coil tube portions are substantially concentric, or a single-layer structure in which such a winding is not performed. it can. In the case of the former lap winding structure, it is possible to have a lap winding structure of triple winding or more. When latent heat recovery is performed from combustion gas, an acidic drain is generated. Therefore, although it is preferable that the coil tube unit is made of a material excellent in acid resistance such as stainless steel, the specific material is not limited to this. .

  When a plurality of coil tube units are provided side by side as in the above-described embodiment, each loop portion of the coil tube body portion is in an upright vertical position, which is generated along with latent heat recovery. An advantage is obtained in that the drain easily flows down from each loop portion. However, the present invention is not limited to this. In this invention, it can also be set as the structure which put in order in the attitude | position which laminated | stacked the several coil tube unit in the up-down direction (substantially perpendicular direction), or in the inclined attitude | position. The total number of coil tube units should just be plural, and the concrete number is not ask | required.

  As the heating medium in the present invention, for example, high-temperature waste gas other than the combustion gas can be used. Also, the fluid to be heated (fluid supplied into the coil tube unit) can be a fluid other than water. The hot water device as used in the present invention means a device having a function of generating hot water, and is used for various types of hot water supply devices for general hot water supply, bath hot water supply, heating, snow melting, and the like, and hot water supply. It is a concept that includes a wide range of equipment for producing hot water.

It is sectional drawing which shows an example of the heat exchanger which concerns on this invention, and a warm water apparatus provided with the same. It is II-II sectional drawing of FIG. It is sectional drawing which shows the laminated structure of the several coiled tube unit used with the heat exchanger shown in FIG. It is a perspective view which shows the coiled tube unit used with the heat exchanger shown in FIG. FIG. 5 is a plan view of FIG. 4. FIG. 5 is a front view of FIG. 4. It is VII-VII sectional drawing of FIG. It is a disassembled perspective view of the coiled tube unit shown in FIG. It is a top view which shows the 1st coil tube part which comprises the coil tube unit shown in FIGS. FIG. 10 is a front view of FIG. 9. It is XI-XI sectional drawing of FIG. It is a top view which shows the 2nd coil tube part which comprises the coil tube unit shown in FIGS. It is a front view of FIG. It is XIV-XIV sectional drawing of FIG. (A) is a top view which shows an example of the conventional coiled tube unit, (b) is the perspective view. FIG. 16 is a front view showing a state in which a plurality of coil tube units shown in FIG. 15 are arranged.

Explanation of symbols

WH Hot water apparatus HE Heat exchanger U Coil tube unit S, S 'Double winding loop structure part 1 Burner 2 Casing 3A, 3B 1st and 2nd coil tube part 4A, 4B Extension tube part 30 Loop part ( Of the first coil tube section)
30a End loop portion 31 Additional loop portion 35 Loop portion (second coil tube portion)

Claims (4)

It has a plurality of coiled tube units arranged in the axial direction,
Each of the coil tube units has a spiral coil tube body portion having a plurality of loop portions arranged in the axial length direction, and extends toward the outside of the coil tube body portion connected to the coil tube body portion. And an extended tube part,
The heating medium passes between the plurality of loop portions from one of the inner region and the outer region of the coil tube portion toward the other, so that the fluid flowing through the coil tube portion can be heated. A heat exchanger,
As the plurality of coil tube units, one provided with a double winding loop structure at both ends or one end of the coil tube body in the axial length direction is used.
The double-wound loop structure portion includes an additional loop portion surrounding the periphery of the terminal loop portion in the terminal loop portion located at the end portion in the axial length direction among the plurality of loop portions of the coil tube body portion. One end of the additional loop portion and the extended tube portion connected to the other end of the additional loop portion, and the additional loop portion is inclined more in the axial length direction than the terminal loop portion. The height difference is small or non-inclined with no inclination,
In the adjacent region of the plurality of coiled tube units, the additional loop portions of the double-wrapped loop structure portion are adjacent to each other. Each of the coil tube units includes first and second coil tube portions that are substantially concentrically wound.
The first coil tube portion is a coil tube portion having the double-wrapped loop structure portion,
The second coil tube portion surrounds a plurality of loop portions other than the additional loop portion in the first coil tube portion, and is formed to have a winding diameter substantially the same as that of the additional loop portion. The heat exchanger according to claim 1, further comprising a plurality of loop portions. A hot water apparatus comprising a burner and a heat exchanger for performing heat recovery from combustion gas generated by the burner to perform hot water heating,
A hot water apparatus, wherein the heat exchanger according to claim 1 or 2 is used as the heat exchanger. A spiral coil body portion having a plurality of loop portions arranged in the axial direction;
An extended tube portion connected to the coil tube portion and extending outward from the coil tube portion;
A coil tube unit for a heat exchanger, comprising:
A double-wound loop structure portion is provided at both ends or one end portion in the axial direction of the coil tube portion,
The double-wound loop structure portion includes an additional loop portion surrounding the periphery of the terminal loop portion in the terminal loop portion located at the end portion in the axial length direction among the plurality of loop portions of the coil tube body portion. One end of the additional loop portion and the extended tube portion connected to the other end of the additional loop portion, and the additional loop portion is inclined more in the axial length direction than the terminal loop portion. A coiled tube unit for a heat exchanger, characterized in that a difference in height is small or non-inclined with no inclination.

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