JP3898583B2 - Heat exchanger header connection structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a header connection structure of a heat exchanger provided with a primary heat exchanger that mainly recovers sensible heat from combustion exhaust and a secondary heat exchanger that mainly recovers latent heat from combustion exhaust, and more particularly, secondary heat exchange The present invention relates to a header connection structure of a heat exchanger that achieves universality by improving workability such as assembly and disassembly by unitizing the heat exchanger.
[0002]
[Prior art]
For example, as shown in FIGS. 9A, 9B, and 10, the heat exchanger used in the high-efficiency water heater is a primary heat exchanger 200 on the upstream side of the combustion exhaust and a downstream side of the combustion exhaust. A secondary heat exchanger 202 is provided, and high efficiency is realized by recovering mainly sensible heat from the combustion exhaust by the primary heat exchanger 200 and recovering mainly latent heat from the combustion exhaust by the secondary heat exchanger 202. ing. In this case, FIGS. 9A and 9B show a wall-mounted water heater, and FIG. 10 shows a stationary water heater.
[0003]
[Problems to be solved by the invention]
By the way, since the secondary heat exchanger 202 is integrated with the exhaust collecting member 204 of the primary heat exchanger 200, the structure becomes complicated, and in order to prevent the drain water generated in the exhaust passage from leaking to the outside, the exhaust collecting For joining the members 204, a method of complete welding (TIG welding) has been adopted.
[0004]
FIG. 11 shows an example of the secondary heat exchanger 202. In the header connection portion 206 of the secondary heat exchanger 202, for example, titanium is used for the heat exchange tube 208. In connection with the exhaust assembly member 204, titanium, stainless steel, and copper alloy are connected, and a seal structure in which an O-ring is doubled is employed. For this reason, the header connecting portion 206 largely protrudes from the side surface of the exhaust assembly member 204. High dimensional accuracy is required for processing, and if the dimensional accuracy is insufficient, assembly is expected to be difficult. Further, such welding of dissimilar metals has a high welding work cost and requires skill to adjust the amount of penetration during welding. For example, Japanese Patent Application Laid-Open No. 2001-336835 “Pipe Connection Structure and Heat Exchanger” includes a technique related to header connection of a heat exchanger.
[0005]
In addition, since the plurality of header connection portions 206 are installed in a scattered manner on the side surface portion of the secondary heat exchanger 202 and the installation position is on the side surface side of the secondary heat exchanger 202, FIG. As shown in FIG. 10A, the inlet-side and outlet-side pipes 210 and 212 are routed to the lower surface side of the wall-mounted water heater, and the side surface side of the stationary-type water heater as shown in FIG. In addition, the piping form in which the inlet side and outlet side pipes 210 and 212 are routed to each other must be provided. Since the pipe form differs depending on the model, there are disadvantages that the number of assembling steps is large and the manufacturing cost is increased.
[0006]
Accordingly, the present invention provides a heat exchanger having a primary heat exchanger and a secondary heat exchanger, in which the header connection of the heat exchanger has been realized with improved workability for assembly and disassembly of the secondary heat exchanger. It is an object to provide a structure.
[0007]
[Means for Solving the Problems]
The header connection structure of the heat exchanger of the present invention that has solved the problem is as follows.
[0008]
The header connection structure of the heat exchanger according to claim 1 includes a primary heat exchanger (primary heat exchanger unit 8) that mainly recovers sensible heat from the combustion exhaust (6), and a secondary that recovers latent heat from the combustion exhaust. A header connection structure of a heat exchanger (4) provided with a heat exchanger (secondary heat exchanger unit 10), wherein the combustion exhaust gas that has passed through the primary heat exchanger is disposed above the primary heat exchanger. An exhaust collecting portion (18) for collecting is provided, and the secondary heat exchanger is installed on the front side of the primary heat exchanger and is mounted in a space portion (20) formed in the exhaust collecting portion. A header connecting part (51) provided with a mounting part (34) and connected to the heat exchanger tube (38, 40, 42) of the secondary heat exchanger is arranged in a lower surface part of the secondary heat exchanger. It is, and arranged on the front side of the primary heat exchanger, the header Characterized by comprising attaching a heated fluid header for connecting conduits to flow through the (water W) to (water supply pipe 62, the heat 交管 64) (50) to the connection part. By adopting such a configuration, header connection portions are collectively arranged at one place, and header connection is simplified.
[0009]
The header connection structure of the heat exchanger according to claim 2 is characterized in that the heat exchanger is formed by unitizing the primary heat exchanger and the secondary heat exchanger. That is, by separating the secondary heat exchanger into a unit that can be separated from the primary heat exchanger, the assembly of both can be improved, and the hot water heater can be easily configured at the site construction, assembling or installing in a narrow installation space. Work can be facilitated.
[0010]
The header connection structure for a heat exchanger according to claim 3 is a relay member (78) joined between an exhaust collecting member (exhaust portion 36) provided in the secondary heat exchanger and an end of the heat exchanger tube. And an insertion portion (86) to be inserted into the relay member, and a sealing member (O-ring 82) is interposed between the insertion portion and the relay member and fixed to the exhaust assembly member. And a header (50). With such a configuration, since the relay member joined to the exhaust collecting member is provided, the sealing member is inserted into the relay member, the insertion portion of the header is inserted, and the header is fixed to the exhaust collecting member. In this way, the insertion portion of the header and the relay member can be brought into close contact with each other, so that the connection structure is simple and the header can be easily attached and detached.
[0011]
The header connection structure for a heat exchanger according to a fourth aspect is characterized in that the header connection portions are collectively arranged on the wall surface of the lower surface portion of the secondary heat exchanger. In this way, the header connection part is collectively arranged on the wall surface of the lower surface of the secondary heat exchanger, so that the availability of space can be improved and the heat exchanger can be reduced in size, and the conventional secondary heat exchange can be achieved. The width direction can be reduced as compared with the case where the header connecting portion is arranged on the side surface of the container.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows the basic structure of a heat exchanger, FIG. 1A shows the configuration of the front side of a heat exchanger built in a wall-mounted water heater, and FIG. 1B shows the side of the heat exchanger. The structure of the side is shown.
[0013]
In the water heater 2, the heat exchanger 4 is a primary heat exchanger unit 8 that mainly recovers sensible heat from the combustion exhaust 6, and a secondary heat exchanger that mainly recovers latent heat from the combustion exhaust 6. It is divided into a secondary heat exchanger unit 10 and is configured independently. In this case, the primary heat exchanger unit 8 is provided with a combustion chamber 12, in which a burner 14 for burning fuel such as gas is built, and an air supply for combustion is provided in the lower portion of the combustion chamber 12. A blower fan 16 is attached as a means. The primary heat exchanger unit 8 is provided with an exhaust collecting portion 18 at an upper portion thereof, and a space portion 20 for attaching / detaching the secondary heat exchanger unit 10 is formed in the exhaust collecting portion 18.
[0014]
The primary heat exchanger unit 8 and the secondary heat exchanger unit 10 are, for example, independent units separated as shown in FIG. 2. The primary heat exchanger unit 8 includes a secondary heat exchanger unit 10. Connection flanges 22 and 24 for attachment are provided, and flanges 26 formed in the secondary heat exchanger unit 10 are fixed to the connection flanges 22 and 24 with fixing screws 28 and 30 as fixing means. Although not shown, the flange 26 is formed with a through hole through which the fixing screws 28 and 30 pass. Reference numeral 32 denotes a drain port through which drain water generated in the secondary heat exchanger unit 10 flows, and a neutralizer (not shown) is connected to the drain port 32.
[0015]
The secondary heat exchanger unit 10 is provided with an exhaust part 36 as an exhaust aggregate member together with a mounting part 34 that can be installed in the space 20 of the exhaust aggregate part 18 on the primary heat exchanger unit 8 side. For example, as shown in FIGS. 3A and 3B and FIG. 4, the mounting portion 34 and the exhaust portion 36 include a plurality of bent heat exchange tubes as a means for mainly recovering latent heat from the combustion exhaust 6. For example, three sets of heat exchanger tubes 38, 40, and 42 are built in, and corrugated tubes made of titanium or a titanium alloy are used for each of the heat exchanger tubes 38, 40, and 42, for example. An exhaust passage 48 defined by a partition plate 46 (FIG. 2) is formed as a means for guiding the combustion exhaust 6 that has passed through the heat exchanger tubes 38 to 42 to the exhaust port 44.
[0016]
In addition, a connection portion 51 for connecting a header 50 as a pipe relay member is set on a specific position such as the lower surface side of the secondary heat exchanger unit 10, in this embodiment, on the lower surface portion of the exhaust portion 36. The connection portion 51 is provided with end portions of the heat exchanger tubes 38 to 42, and plate-like header fixing portions 52 are attached to the exhaust portion 36 with fixing screws 54 disposed at a plurality of locations. . The header fixing portion 52 is integrally formed with an inlet header 56 and an outlet header 58. The inlet header 56 is connected to an inlet end of the heat exchanger tubes 38 to 42 and a water supply pipe 62 connected to the water supply port 60 {(A)} in FIG. Are connected to the outlet ends of the three sets of heat exchanger tubes 38 to 42 and the heat exchanger tube 64 of the primary heat exchanger unit 8. The hot water supply port 66 {(A)} in FIG. 1 installed adjacent to the water supply port 60 is connected to the hot water supply side of the heat exchanger tube 64 of the primary heat exchanger unit 8 via the connecting pipe 68. Accordingly, for example, the water W supplied from the water supply pipe 62 flows into the heat exchange pipes 38 to 42 through the inlet header 56 and is heated mainly by the recovery of latent heat from the combustion exhaust 6, and then is discharged as hot water HW. It flows from the header 58 to the heat exchanger tube 64 side of the primary heat exchanger unit 8, and the hot water HW can be taken out from the hot water supply port 66 shown in FIG.
[0017]
Further, in the connection portion between the inlet header 56 and the outlet header 58 and the heat exchanger tubes 38 to 42, for example, FIG. 5 {sectional view taken along the line VV in FIG. 3B} and FIG. 6 {FIG. As shown in the V-V line exploded sectional view}, a circular opening 72 is formed in the wall surface member 70 of the exhaust portion 36, and an annular flange portion 74 having a constant width bent in the outer surface direction is formed. ing. The wall surface member 70 is formed of, for example, a stainless plate. Corresponding to the opening 72, for example, a connection end portion 76 of the heat exchanger tube 38 of the heat exchanger tubes 38 to 42 is guided, and an annular relay member 78 is connected to the connection end portion 76 by welding. Part.
[0018]
The relay member 78 has a tapered sealing portion 84 to be in close contact with the O-ring 82 that is a sealing member, a fitting portion 88 for fitting the insertion portion 86 of the header 50, and an opening 72 on the wall surface member 70 side. A flange portion 90 to be welded to is formed. That is, the flange portion 90 of the relay member 78 is inserted into the flange portion 74 of the opening 72 of the wall surface member 70, and the flange portions 74 and 90 are integrated by welding, for example. That is, the connection end portion 76 of the heat exchanger tubes 38 to 42 is connected to the wall surface member 70 of the exhaust portion 36 via the relay member 78 and is opened.
[0019]
Further, the insertion portion 86 of the header 50 is formed with water guide holes 92 corresponding to the heat exchanger tubes 38 to 42, and supports the O-ring 82 together with a small-diameter portion 94 to which the O-ring 82 is attached at the tip side. A step 96 is formed.
[0020]
A fixing nut 98 corresponding to the fixing screw 54 is fixed to the wall surface member 70 of the exhaust portion 36 as a fixing means of the header fixing portion 52 by welding. Therefore, if the insertion portion 86 with the O-ring 82 attached is inserted into the relay member 78 and the fixing screw 54 inserted into the fixing hole 100 formed on the header fixing portion 52 side is attached to the fixing nut 98 with a screwdriver or the like, Each relay member 78 and the header 50 can be firmly fixed, and a seal by an O-ring 82 is added to the coupling between the insertion portion 86 inserted into the fitting portion 88 and the fitting portion 88, so that a highly close contact state, that is, A watertight structure is realized.
[0021]
In the embodiment described above, the following effects can be obtained. In the heat exchanger 4 having the secondary heat exchanger unit 10 as a secondary heat exchanger capable of dramatically increasing the thermal efficiency of the water heater 2, the secondary heat exchanger unit 10 is attached and detached with fixing screws 28 and 30. Since the secondary heat exchanger unit 10 having different specifications can be incorporated at the time of manufacture, the heat exchanger 4 realizes a highly versatile and suitable form for mass production. Yes. That is, since the secondary heat exchanger unit 10 can be attached and detached at the exhaust collecting portion 18 of the primary heat exchanger unit 8, the secondary heat exchanger unit 10 can be divided and easily separated by the exhaust collecting portion 18. Can do.
[0022]
Moreover, since it was set as the independent structure which can isolate | separate the primary heat exchanger unit 8 and the secondary heat exchanger unit 10, the secondary heat exchanger unit 10 is divided into 3 parts by the front and back flat plates, and the side plate which connects these. In addition, the structure can be simplified, for example, the joint can be continuously welded without requiring skill, and can be assembled by seam welding that does not cause drain leakage.
[0023]
Further, in order to obtain certainty against drain leakage, a component obtained by integrating the front plate and the side plate, which are component parts, into the secondary heat exchanger unit 10 and performing drawing processing may be used. Moreover, since the same kind of metal as that of the heat exchanger tubes 38 to 42 can be used for the relay member 78 used for connection between the heat exchanger tubes 38 to 42 and the wall surface member 70 of the exhaust portion 36, the dissimilar metal of titanium and copper alloy can be used. Direct welding can be performed without the problem of electrolytic corrosion due to bonding, and since the sealing portion by the O-ring 82 is one place, a highly reliable connection structure for preventing water leakage can be realized. .
[0024]
In addition, since the header 50 is concentrated at a specific location of the secondary heat exchanger unit 10, for example, at one location on the lower surface side thereof, the secondary heat is increased without increasing the pressure loss, for example, as shown in FIG. The left and right mounting directions of the header 50 can be arbitrarily selected with respect to the exchanger unit 10, and the fixing can be performed only by the mounting operation of the common fixing screw 54.
[0025]
As a result, the heat exchanger 4 of the wall-mounted water heater 2 shown in FIGS. 1A and 1B can perform, for example, secondary heat exchange as shown in FIGS. 8A and 8B. The mounting direction of the header 50 with respect to the heater unit 10 can be set freely (universalization), and the stationary water heater 102 can be configured only by changing the extraction direction of the water supply pipe 62 and the heat exchange pipe 64. In addition, it is possible to arbitrarily design the secondary heat exchanger unit 10 according to the capacity and attach the secondary heat exchanger unit 10 having different specifications to the common primary heat exchanger unit 8. It is possible to facilitate provision of equipment according to needs such as specification changes, and to develop a fine-grained product configuration.
[0026]
According to experiments, the secondary heat exchanger unit 10 can be realized with a volume of only about 20 × 20 × 10 cm, and the addition of the secondary heat exchanger unit 10 can improve the thermal efficiency by 10% or more. Has been confirmed.
[0027]
In the embodiment, the hot water heater using gas combustion as a heat source has been described as an example. However, the heat exchanger according to the present invention includes a fuel other than a gas as well as an electric heat or solar heat as a heat source. Applicable. Moreover, the heating medium other than water W etc. can be used for the to-be-heated fluid.
[0028]
【The invention's effect】
As described above, according to the present invention, the following effects can be obtained.
[0029]
According to the header connection structure of the heat exchanger according to claim 1, in the heat exchanger provided with the primary heat exchanger and the secondary heat exchanger, the workability of assembly and disassembly of the secondary heat exchanger can be improved freely. (Universalization) can be realized. That is, a header connecting portion provided in the heat exchanger tube of the secondary heat exchanger is arranged at a specific location on the outer wall portion of the secondary heat exchanger, and a pipe line through which a fluid to be heated flows is supplied to the header connecting portion. Since the header to be connected is attached, the header connection portions are collectively arranged at one place, and the connection of the header can be simplified.
[0030]
According to the header connection structure of the heat exchanger according to claim 2, the heat exchanger unitizes the primary heat exchanger and the secondary heat exchanger. Can be easily configured, and assembly or installation work in a narrow installation space can be facilitated.
[0031]
According to the header connection structure of the heat exchanger according to claim 3, a relay member joined between the exhaust assembly member provided in the secondary heat exchanger and the end of the heat exchanger tube, and the relay member inside Since it has an insertion portion to be inserted and a header that is inserted between the insertion portion and the relay member and is fixed to the exhaust assembly member, the sealing member is inserted into the relay member. By inserting the header insertion part and fixing the header to the exhaust assembly member, the header insertion part and the relay member can be brought into close contact with each other, the connection structure is simple, and the header can be easily attached and detached. it can.
[0032]
According to the header connection structure of the heat exchanger according to claim 4, since the header connection portions are collectively arranged on the lower surface side of the secondary heat exchanger, the availability of space can be improved and the heat exchanger can be downsized. Therefore, it is possible to reduce the size of the device as compared with the case where the header connection portion is disposed on the side surface side of the conventional secondary heat exchanger.
[Brief description of the drawings]
FIG. 1 shows a wall-mounted water heater as an embodiment of a header connection structure of a heat exchanger, (A) is a diagram showing an internal configuration viewed from the front, and (B) is an internal configuration viewed from the side. FIG.
FIG. 2 is a view showing attachment and detachment of a primary heat exchanger unit and a secondary heat exchanger unit.
3A and 3B show a header connection structure in a secondary heat exchanger unit, in which FIG. 3A shows a configuration viewed from the front, and FIG. 3B shows a configuration viewed from the bottom.
FIG. 4 is a diagram showing a configuration of the secondary heat exchanger unit as viewed from the side of the header connection structure.
FIG. 5 is a cross-sectional view taken along line VV in the header connection structure shown in FIG.
6 is an exploded cross-sectional view taken along line VV in the header connection structure shown in FIG.
FIG. 7 is a diagram showing the mounting direction of the header in the secondary heat exchanger unit.
FIG. 8 shows a stationary water heater as an embodiment of a header connection structure of a heat exchanger, (A) is a diagram showing an internal configuration viewed from the front, and (B) is an internal configuration viewed from the side. FIG.
9A and 9B show a wall-mounted water heater using a header connection structure of a conventional heat exchanger, FIG. 9A is a diagram showing an internal configuration viewed from the front, and FIG. 9B is an internal configuration viewed from the side. FIG.
FIG. 10 is a diagram showing an internal configuration as seen from the front of a stationary water heater using a header connection structure of a conventional heat exchanger.
FIG. 11 is a view showing a header connection form of a conventional heat exchanger.
[Explanation of symbols]
2 Water heater 4 Heat exchanger 6 Combustion exhaust 8 Primary heat exchanger unit (primary heat exchanger)
10 Secondary heat exchanger unit (secondary heat exchanger)
36 Exhaust section (exhaust assembly member)
38, 40, 42 Heat exchange pipe 50 Header 51 Connection section 62 Water supply pipe (pipe)
78 Relay member 82 O-ring (sealing member)
86 Insertion section W Water (heated fluid)

Claims (4)

A heat exchanger header connection structure comprising a primary heat exchanger that mainly recovers sensible heat from combustion exhaust, and a secondary heat exchanger that recovers latent heat from the combustion exhaust,
An exhaust collecting portion for collecting the combustion exhaust gas that has passed through the primary heat exchanger at an upper portion of the primary heat exchanger;
The secondary heat exchanger is installed on the front side of the primary heat exchanger, and includes a mounting portion that is mounted in a space portion formed in the exhaust assembly portion.
Header connection parts connected to the heat exchanger tubes of the secondary heat exchanger are arranged collectively on the lower surface part of the secondary heat exchanger, and arranged on the front side of the primary heat exchanger,
A header connection structure for a heat exchanger, wherein a header for connecting a pipe for allowing a fluid to be heated to flow is attached to the header connection portion.   2. The heat exchanger header connection structure according to claim 1, wherein the heat exchanger is formed by unitizing the primary heat exchanger and the secondary heat exchanger. A relay member joined between an exhaust collecting member provided in the secondary heat exchanger and an end of the heat exchanger tube;
A header that includes an insertion portion that is inserted into the relay member, and that is fixed to the exhaust assembly member by inserting a sealing member between the insertion portion and the relay member;
The header connection structure for a heat exchanger according to claim 1, comprising: 2. The header connection structure for a heat exchanger according to claim 1, wherein the header connection portions are collectively arranged on a wall surface of a lower surface portion of the secondary heat exchanger.

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