JP5472703B2 - Heat exchanger and combustion apparatus - Google Patents

Description

  The present invention relates to a heat exchanger and a combustion apparatus, and more particularly to a combustion apparatus including a heat exchanger for recovering latent heat.

  Combustion devices that burn gas or liquid fuel are often used as heat sources for water heaters, bath devices, and the like. In recent years, from the viewpoint of energy saving and environmental protection, a combustion apparatus having higher thermal efficiency than the conventional combustion apparatus is desired. In order to solve this demand, a combustion apparatus having a plurality of heat exchangers and a latent heat recovery type combustion apparatus capable of recovering latent heat in addition to sensible heat of combustion gas have been proposed.

  A conventional latent heat recovery type combustion apparatus has a configuration as disclosed in, for example, Patent Document 1, and mainly uses a heat exchanger for recovering sensible heat (primary heat exchange) for recovering sensible heat of combustion gas. And a heat exchanger (secondary heat exchanger) for recovering the latent heat, which mainly recovers the latent heat of the combustion gas (and recovers the remaining sensible heat).

  By the way, since the secondary heat exchanger is intended to recover even the latent heat of the combustion gas, an efficient configuration has been desired.

  Therefore, in the conventional combustion apparatus, the heat receiving tubes constituting the secondary heat exchanger have a meandering shape, and a plurality of heat receiving tubes having the same shape are arranged adjacent to each other so that the flow of hot water is parallel. Further, the secondary heat exchanger is provided with a deflecting member in the vicinity of the position where the heat receiving pipe is folded back. As a result, the combustion gas can pass along the meandering heat receiving pipe, so that the combustion gas is in a counter flow with the hot water flowing through the heat receiving pipe, and more efficient heat exchange is possible.

JP 2009-133551 A

  However, in the combustion apparatus of the prior art, the deflecting member is located in the vicinity of the surface (the surface on the upstream side in the flow direction of the combustion gas) opposite to the surface (the surface on the upstream side in the flow direction of the combustion gas). Combustion gas did not flow through the heat receiving pipe (because the fluid tried to pass through a path with low resistance), and there was a complaint that heat exchange was not performed at that position.

  Therefore, in order to eliminate the dissatisfaction, in the combustion apparatus of the prior art, the deflecting members are arranged at all positions where the heat receiving pipe is folded, and the combustion gas is forced to pass through the opposite surface of the deflecting member. Although a countermeasure has been proposed, when the deflecting members are arranged at all the folding positions of the heat receiving pipe, the ventilation resistance to the combustion gas in the secondary heat exchanger significantly increases, and the combustion state of the combustion section that generates the combustion gas There was a concern of causing problems.

  Then, this invention makes it a subject to develop the heat exchanger and combustion apparatus which can aim at the further improvement of thermal efficiency, without producing a malfunction at the time of combustion.

The invention according to claim 1 for solving the above-described problem has a casing part into which combustion gas is introduced, and hot water or a heat medium recovers heat of the combustion gas in the casing part. A heat exchanger for exchanging heat, comprising a plurality of heat receiving tubes through which hot water or a heat medium flows and a regulating plate for restricting the flow direction of the combustion gas, the plurality of heat receiving tubes adjacent in parallel The heat receiving pipe includes a plurality of crossing portions that cross the flow direction of the combustion gas, a crossing portion that is located upstream in the flow direction of hot water or a heat medium, and a crossing portion that is located downstream. And the folding part is capable of folding back the flow of hot water or heat medium supplied from the upstream crossing part and supplying the flow to the downstream crossing part. It may have a vent to allow passage of a portion of the combustion gas, wherein the vent, receiving It is located near the connection part between the crossing part and the folded part of the pipe and upstream of the flow direction of the combustion gas in the heat receiving pipe, and is elongated in the arrangement direction of the heat receiving pipe, or aligned in the arrangement direction of the heat receiving pipe The restriction plate is a plate-like member having at least a flat surface portion and a curved surface portion, and the flat surface portion is provided with the ventilation portion and intersects the flow direction of the combustion gas. It is disposed at an angle and is inclined upwardly from the curved surface portion toward the protruding direction, and the curved surface portion is fixed to the inner wall surface of the housing portion, and the inner wall surface of the housing portion and the The heat exchanger extends across a gap formed between the folded portions, and flows the combustion gas that has passed through the ventilation portion to a downstream heat receiving pipe .

Generally, in a latent heat recovery type heat exchanger, sensible heat of high-temperature combustion gas is recovered by a sensible heat recovery type heat exchanger (primary heat exchanger) located upstream of the heat exchanger. The combustion gas passing through the latent heat recovery type heat exchanger (secondary heat exchanger) located downstream of the primary heat exchanger is at a low temperature (lower temperature than when passing through the primary heat exchanger). That is, in order to recover latent heat from a low-temperature combustion gas and heat hot water or a heat medium, a configuration for efficiently recovering heat has been desired for the latent heat recovery type heat exchanger.
Therefore, in the heat exchanger of the present invention, the heat receiving tube has a shape meandering substantially by a transverse portion and a folded portion. As a result, even in the same volume, the overall length can be increased due to the meandering shape of the heat receiving tube, so that the surface area of the heat receiving tube is increased, the effective area that can be in contact with the combustion gas is increased, and the thermal efficiency is high. Become.

Furthermore, since the heat exchanger of the present invention includes a regulating plate having a ventilation part that allows passage of some combustion gases, the combustion gas passes through a place where it is difficult to flow in the conventional heat exchanger. Can be made. That is, according to the heat exchanger of the present invention, the combustion gas can flow into the vicinity of the surface of the regulating plate on the downstream side in the flow direction of the combustion gas via the ventilation portion, thereby further increasing the thermal efficiency. it can.
In addition, by passing a part of the combustion gas from the ventilation section, it is possible to prevent the ventilation resistance of the combustion gas from rising excessively in the casing, so even if multiple restriction plates are provided, there is a problem during combustion. Will not cause.
Therefore, if it is the heat exchanger of this invention, the further improvement of thermal efficiency can be aimed at, without producing a malfunction at the time of combustion.

In the heat exchanger according to the present invention, the ventilation portion is disposed in the vicinity of a connection portion between the transverse portion and the folded portion of the heat receiving pipe .

According to such a configuration, since the ventilation portion is disposed in the vicinity of the connection portion between the transverse portion and the folded portion of the heat receiving pipe, the combustion gas can be flowed to a place that is relatively difficult to flow.
Here, as is well known, it is known that the fluid tends to flow along a path having a low resistance. That is, when the combustion gas flows in the vicinity of the folded portion, the combustion gas tends to pass through a gap between the casing portion having a relatively small resistance and the folded portion of the heat receiving pipe. For this reason, if a ventilation part is arrange | positioned in the clearance gap vicinity between a folding | turning part and a housing | casing part, since most combustion gas concentrates and passes through the said clearance gap with small resistance, thermal efficiency may fall.
Therefore, in the heat exchanger of the present invention, since the ventilation portion is arranged in the vicinity of the connection portion between the folding portion and the transverse portion, the combustion gas hardly flows into the gap between the folding portion and the casing portion, and the regulation plate The combustion gas can be flowed to the heat receiving pipe located near the surface on the downstream side in the flow direction of the combustion gas (a place where it is relatively difficult to flow). Thereby, in the heat exchanger of this invention, since the location where combustion gas does not reach with respect to a heat receiving pipe is almost lost, heat exchange can be performed more efficiently.

In the heat exchanger according to the present invention, the plurality of heat receiving tubes are arranged adjacent to each other in parallel, and the ventilation portion has a long hole shape that is long in the arrangement direction of the heat receiving tubes, or is arranged in the arrangement direction of the heat receiving tubes. It is an aggregate of a plurality of holes.

According to the configuration in which the ventilation portion has a long hole shape, since the ventilation portion has a long hole shape (for example, a slit shape or an “S” shape) that is long in the arrangement direction of the heat receiving tubes, the processing is relatively easy. . Further, by processing the ventilation portion to a length corresponding to the arrangement of the heat receiving tubes, it is possible to improve the thermal efficiency more effectively.

In the heat exchanger of the present invention, before Symbol vent is an aggregate of a plurality of holes, said holes, but it may also be those in a row in the array direction of the heat receiving tube.

  According to such a configuration, the ventilation portion is an assembly of a plurality of holes, and since the holes are arranged in the arrangement direction of the heat receiving tubes, for example, by providing the same number of holes as the arrangement of the heat receiving tubes, The combustion gas can be circulated intensively to the heat receiving pipe. Thereby, a heat exchanger with higher thermal efficiency can be provided.

The present invention, said regulating plate is a plate-like member having at least flat portion, said flat portion, together with the vent portion is provided, that is arranged at an angle intersecting the flow direction of the combustion gases.

  The heat exchanger of the present invention is a plate-like member in which the restriction plate has at least a flat portion, and the flat portion is at an angle intersecting with the flow direction of the combustion gas, so the combustion gas flowing through the heat exchanger is It collides with the flat part and stays securely. In addition, since the ventilation portion is provided in the flat portion, the combustion gas can also flow to the vicinity of the surface opposite to the collision surface of the combustion gas in the flat portion (the surface on the downstream side in the combustion gas flow direction). it can. Therefore, according to the heat exchanger of this invention, it is possible to improve thermal efficiency more effectively.

The present invention, said regulating plate, Ri Contact further includes a curved portion, the flat portion that are inclined upward gradient from the curved portion toward the protruding direction. Further, it is desirable that the flat surface portion is disposed at one end portion of the curved surface portion.

In the heat exchanger of the present invention, the regulating plate further has a curved surface portion, and a flat surface portion is disposed at one end of the curved surface portion, and the flat surface portion is inclined upwardly from the curved surface portion toward the protruding direction. ing. Thereby, since the flow of the combustion gas is regulated along the curved surface portion and the inclined flat surface portion, the combustion gas is not excessively resistant. That is, the flow of the combustion gas is temporarily retained by the flat portion, but flows almost smoothly in the exhaust direction by the curved portion and the inclined flat portion.
Therefore, in the heat exchanger of the present invention, the restriction plate does not excessively obstruct the flow of the combustion gas, so that even when a plurality of restriction plates are provided, no problem is caused during combustion. That is, according to the heat exchanger of the present invention, it is possible to improve the thermal efficiency by delaying the exhaust of the combustion gas by the regulation plate while minimizing an increase in the combustion gas ventilation resistance to prevent a malfunction at the time of combustion. Can do.

In the heat exchanger according to the present invention, it is preferable that a plurality of the restriction plates are provided and arranged and fixed in a staggered manner in the flow direction of the combustion gas on the side wall of the casing. ( Claim 2 )

According to such a configuration, since the plurality of regulating plates are arranged in a staggered manner in the flow direction of the combustion gas, the passing combustion gas can flow while meandering in the same manner as the heat receiving pipe. Thereby, since exhaust of combustion gas is delayed more, the further improvement in thermal efficiency can be expected.
For example, by arranging the restriction plate at a position where all the turn-back portions are arranged, the flow of the combustion gas and the flow of the heat medium flowing through the heat receiving pipe can be in a counterflow relationship at all positions of the heat receiving pipe. A heat exchanger with higher thermal efficiency can be provided.

According to a third aspect of the present invention, there is provided a combustion means for combusting fuel, a combustion gas passage through which combustion gas generated by a combustion operation in the combustion means flows downward, and the combustion gas passage. An exhaust collecting portion that exists downstream in the flow direction of the combustion gas, accepts and passes the combustion gas that has passed through the combustion gas passage, and changes the flow direction upward, and combustion sent from the exhaust collecting portion A primary heat exchanger capable of heating hot water or a heat medium by exchanging heat with the heat exchange exhaust section that can receive and pass gas and flow upward, and the combustion gas flowing through the combustion gas passage; A combustion apparatus comprising a secondary heat exchanger disposed in a heat exchange exhaust section, wherein the secondary heat exchanger is the heat exchanger according to claim 1 or 2 .

  A combustion apparatus according to the present invention includes a combustion means, a combustion gas passage, an exhaust collecting part, a heat exchange exhaust part, a primary heat exchanger, and the heat exchanger according to any one of claims 1 to 7. Has been. That is, according to the combustion apparatus of the present invention, even when a plurality of regulating plates are provided, it is possible to further improve the thermal efficiency without causing problems during combustion.

  According to the present invention, by providing the ventilation portion in the restriction plate, the combustion gas can flow through the ventilation portion to the place where the combustion gas hardly flows, and therefore, the thermal efficiency can be further improved. Further, by flowing a part of the combustion gas from the ventilation portion, it is possible to prevent an excessive increase in the ventilation resistance of the combustion gas, so that it is possible to prevent problems during combustion that can occur by providing a plurality of regulating plates.

It is a front view which shows the state which fractured | ruptured a part of combustion apparatus which concerns on embodiment of this invention. It is AA sectional drawing of FIG. It is a perspective view which shows an exhaust flow path formation member. It is an expanded view which shows an outer frame member. It is a perspective view which shows the state in the middle of the bending process of an outer frame member. It is a perspective view of the outer frame member seen from another angle. It is a disassembled perspective view which shows an exhaust flow path formation member. It is a perspective view which shows a heat receiving pipe. It is a perspective view which shows a control board. It is a top view which shows the modification (elliptical shape) of a ventilation part. It is a top view which shows the modification (double slit) of a ventilation part. It is a top view which shows the modification ("S" character type) of a ventilation part. It is a top view which shows the modification of a ventilation part, (a) is a square hole, (b) is a circular hole. It is a figure which shows the modification of a ventilation part, (a) is a perspective view, (b) is AA sectional drawing of (a). It is a top view which shows the modification (notch shape) of a ventilation part.

  Then, the combustion apparatus 1 which concerns on embodiment of this invention is demonstrated in detail, referring drawings. In the following description, the vertical / horizontal positional relationship will be described based on a normal installation state unless otherwise specified.

  As shown in FIG. 1, the combustion device 1 is a so-called latent heat recovery type combustion device including a combustion section 2 (combustion means), a primary heat exchanger 20, and a secondary heat exchanger 30. The combustion apparatus 1 includes a combustion case 3 and an exhaust collecting unit 5 below the combustion unit 2. A heat exchange exhaust unit 6 is provided on the side of the combustion unit 2. Further, a neutralizer 7 is provided below the exhaust collecting portion 5. The combustion case 3 and the heat exchange exhaust unit 6 communicate with an exhaust collecting unit 5 provided on the bottom side of the combustion device 1. As a result, a space is formed in the combustion device 1 so as to have a substantially “U” -shaped cross section from the combustion case 3 to the heat exchange exhaust 6 through the exhaust collecting portion 5.

  As shown in FIG. 1, the combustion unit 2 includes an air case 8, a fuel spray nozzle 10, a blower 11, a combustion cylinder 12, and the like. The combustion unit 2 is a so-called reverse combustion type, and can form a flame downward. That is, the combustion unit 2 operates the blower 11 to introduce combustion air into the air case 8 and directs the liquid fuel supplied from a fuel supply source (not shown) downward from the fuel spray nozzle 10. It is set as the structure which can be sprayed and combusted in the combustion cylinder 12. FIG.

  The combustion case 3 is located on the lower side with respect to the combustion unit 2 and is a portion (combustion gas passage) through which high-temperature combustion gas generated in accordance with the combustion operation in the combustion unit 2 flows. A water pipe 15 is wound around the combustion case 3 in order to prevent an excessively high temperature due to the high-temperature combustion gas flowing inside. A connecting portion 16 is provided on one end side of the water pipe 15, and a pipe 38, which will be described later, is connected thereto. The other end of the water pipe 15 is connected to a primary water inlet 25 of the primary heat exchanger 20 described later.

  A primary heat exchanger 20 is provided at a lower end side portion of the combustion case 3. The primary heat exchanger 20 is mainly for recovering sensible heat contained in the combustion gas flowing through the combustion case 3. The primary heat exchanger 20 is configured by a so-called fin-and-tube heat exchanger. That is, the primary heat exchanger 20 has a series of water pipes 21 bent in a substantially “U” shape, and the water pipes 21 are inserted so as to cross the combustion case 3. A large number of fins 22 are attached to the water pipe 21. The primary heat exchanger 20 can heat-heat the hot water (heat medium) flowing in the water pipe 21 by heat exchange with the high-temperature combustion gas flowing in the combustion case 3.

  The water pipe 21 has a primary water outlet 23 on one end side and a primary water inlet 25 on the other end side. The primary water outlet 23 is connected to a hot water supply destination such as a curan through a pipe or the like (not shown). On the other hand, a water pipe 15 wound around the combustion unit 2 is connected to the primary water inlet 25.

  The exhaust collecting portion 5 is a portion that is disposed below the combustion case 3 and communicates directly with the combustion case 3. The exhaust collecting portion 5 has an internal space that extends in the width direction of the combustion device 1 (left-right direction in FIG. 1) on the bottom side of the combustion device 1. Further, the exhaust collecting portion 5 is also in communication with a heat exchange exhaust portion 6 disposed on the side of the combustion case 3. Specifically, as shown in FIG. 2, the exhaust collecting part 5 has a convex space (conduction part) 5 a in which a part located at the lower part of the heat exchange exhaust part 6 enters the heat exchange exhaust part 6 side. The convex space 5a and the heat exchange exhaust part 6 communicate with each other. The convex space 5 a is arranged at one corner of the heat exchange exhaust unit 6. Therefore, the exhaust collecting portion 5 functions as a portion that causes the combustion gas flowing downward in the combustion case 3 to flow in and flows out the combustion gas toward the heat exchange exhaust portion 6 in the horizontal direction. That is, the exhaust collecting part 5 functions as a part for turning the flow direction of the combustion gas flowing downward toward the upper side and letting it flow out in the horizontal direction.

  As shown in FIG. 2, the heat exchange exhaust part 6 has a space 6 b surrounded on all sides by an outer wall member (housing part) 6 a. In addition, a heat insulating material (not shown) is attached to the heat exchange exhaust 6 so as to surround the outer periphery of the outer wall member 6a.

  The space 6b is partitioned into two regions by a partition member 6h. Specifically, the partition member 6h is attached so as to cut the heat exchange exhaust part 6 vertically. Thereby, the space 6b is divided into a heat exchange chamber 17 in which a secondary heat exchanger 30 described later is provided, and an exhaust passage portion 18.

  More specifically, a heat exchange chamber 17 is disposed on the front side of the combustion apparatus 1, and an exhaust passage portion 18 is disposed on the back side of the combustion apparatus 1 so as to be adjacent to the heat exchange chamber 17. The chamber 17 is disposed so as to be located upstream of the exhaust gas flow portion 18 in the flow direction of the combustion gas. The partition member 6h is provided with a communication port 6i on the upper side of the space 6b, and allows the heat exchange chamber 17 and the exhaust flow path portion 18 to communicate with each other.

In the heat exchange chamber 17, the flow path cross-sectional area of the heat exchange arrangement region 6x in which the secondary heat exchanger 30 is arranged is large enough to accommodate the secondary heat exchanger 30 with almost no gap.
Therefore, almost all the combustion gas that has flowed into the upstream region 6y of the heat exchange exhaust section 6 is located between the heat receiving pipes 31 of the secondary heat exchanger 30 disposed in the heat exchange region 6x from below. Will pass to the downstream region 6z side.

  More specifically, the heat exchange chamber 17 communicates with the exhaust collecting portion 5 through an inlet 6e provided on the lower end side. The introduction port 6e is an opening through which the combustion gas passes in the horizontal direction, and is arranged on the side surface side of the heat exchange chamber 17. That is, the combustion gas that has passed through the convex space (conducting portion) 5a of the exhaust collecting portion 5 is introduced into the heat exchange chamber 17 in the horizontal direction via the inlet 6e. Thereby, the drain generated in the heat exchange chamber 17 is prevented from flowing into the upstream side in the flow direction of the combustion gas through the inlet 6e. The bottom surface of the heat exchange chamber 17 is a tray portion 17a that receives the drain generated in the heat exchange chamber 17, and has a weir portion 17b that is erected on the edge and formed by bending. That is, the drain that has fallen on the tray part 17a is not leaked to the exhaust collecting part 5 by the weir part 17b.

  Further, a drain discharge port 47 is provided in the tray part 17a. In FIG. 1, the drain discharge port 47 is connected to the neutralizer 7 provided below the exhaust collecting portion 5 through a pipe 48 as indicated by a two-dot chain line. That is, the drain that has fallen on the tray portion 17 a is discharged to the pipe 48 through the drain discharge port 47. Thereby, a series of drain discharge systems is formed in which the drain generated in the secondary heat exchanger 30 is guided to the neutralizer 7 by bypassing the exhaust collecting portion 5.

  On the other hand, the exhaust passage portion 18 is disposed further inside the outer wall member 6a. Specifically, as shown in FIGS. 2 and 3, the exhaust flow path portion 18 is configured by an exhaust flow path forming member 14 that is a separate member from the outer wall member 6 a. The exhaust flow path forming member 14 is made of an aluminum plated steel plate, and includes an outer frame member 14a and flow path partition members 14b and 14c (FIG. 7). In the present invention, the exhaust flow path forming member 14 is not limited to one made of an aluminum plated steel plate, and may be made of a metal such as stainless steel.

  As shown in FIGS. 4 and 5, the outer frame member 14a is formed by bending a single plate member along a two-dot chain line, and as shown in FIG. 6, the convex space of the exhaust collecting portion 5 described above. 5a, the exhaust passage 18 and the filling space 24 filled with the sound absorbing material 29 (sound insulating material, FIG. 7) located between them are integrally formed. Specifically, as described above, since the outer frame member 14a is formed by bending one plate member, a gap communicating upward from the convex space 5a is not formed. That is, the outer frame member 14a is hardly formed with a gap through which sound can propagate upward from the convex space 5a. Thereby, even if the combustion sound generated in the combustion section 2 is directed upward (FIG. 2) above the convex space 5a, the sound is absorbed by the sound absorbing material 29 disposed in the filling space 24, and thus the convex space 5a. Propagated combustion noise hardly reaches the exhaust passage 18. That is, in the combustion apparatus 1 of the present embodiment, the combustion noise directed upward (FIG. 2) from the convex space 5a hardly leaks to the outside through the exhaust passage portion 18. The sound absorbing material 29 is made of a material containing a gap. Specifically, the sound absorbing material 29 has a plurality of pores in the form of a sponge, such as a so-called silicon sponge, which has voids inside by binding fibers such as so-called glass wool, rock wool, and ceramic fiber with a binder. It is comprised with the porous body etc. which have. In the present embodiment, glass wool bound with a binder and having a shape adjusted to match the internal shape (substantially rectangular parallelepiped shape) of the filling space 24 is mounted.

  Then, inside the outer frame member 14a formed by the bending process, as shown in FIG. 7, it flows into the exhaust passage portion 18 located above (downstream in the flow direction of the combustion gas with respect to the convex space 5a). A flow partitioning member 14b is mounted and the flow path of the exhaust flow path portion 18 is folded, and the flow is passed into the convex space 5a located below (upstream in the flow direction of the combustion gas with respect to the exhaust flow path 18). A road partition member 14c is mounted to form an arc-shaped flow path. The channel partition members 14b and 14c are fixed to the outer frame member 14a by spot welding.

  That is, the exhaust flow path portion 18 has a lower flow path forming portion (first flow path portion, exhaust flow path) 18s into which the combustion gas first flows from the communication port 6i, and a combustion gas with respect to the lower flow path forming portion 18s. And an upper flow path forming part (second flow path part, exhaust flow path) 18t located downstream in the flow direction. Specifically, as shown in FIG. 2, the lower flow path forming portion 18s is located on the back side of the heat exchange chamber 17, and the upper flow path forming portion 18t is located on the back side of the lower flow path forming portion 18s. Yes.

  More specifically, the lower flow path forming portion 18s and the upper flow path forming portion 18t are partitioned by the flow path partition member 14b, and form a U-shaped flow path having a “U” -shaped cross section. Yes. The flow path partition member 14b is provided so as to cut the exhaust flow path portion 18 vertically. The flow path partitioning member 14b is provided with a communication port 6j on the lower side of the exhaust flow path section 18, and communicates the lower flow path forming section 18s and the upper flow path forming section 18t. That is, the combustion gas that has passed downward through the lower flow path forming portion 18s is redirected at one end in the horizontal direction at the communication port 6j and flows into the upper flow path forming portion 18t.

  The upper flow path forming part 18t allows the combustion gas to pass upward, and communicates with a conversion flow path forming member 19 described later at the upper part of the upper flow path forming part 18t. Specifically, the upper flow path forming portion 18 t is provided with a communication port 6 k at the upper portion, and the combustion gas that has passed upward through the communication port 6 k is introduced into the conversion flow channel forming member 19.

  The conversion flow path forming member 19 is arranged on the upper side of the heat exchange exhaust section 6, and the combustion gas flows in the flow direction of the combustion gas passing through the heat exchange chamber 17 or the combustion gas passing through the upper flow path forming section 18 t. It is possible to flow in a direction crossing the flow direction. The conversion flow path forming member 19 has an exhaust port 6d communicating with the external atmosphere. That is, the combustion gas that has passed through the conversion flow path forming portion 19 passes through the exhaust port 6d in a substantially horizontal direction and is discharged to the outside.

  As shown in FIGS. 1 and 2, a secondary heat exchanger 30 is disposed in the heat exchange chamber 17 of the heat exchange exhaust unit 6. The secondary heat exchanger 30 includes a plurality of heat receiving pipes 31 (in this embodiment, six as shown in FIG. 1), a water inlet side header 32, and a water outlet side header 33. The heat receiving pipes 31 are excellent in thermal conductivity and are formed by piping having a smooth surface, and a plurality of the heat receiving pipes 31 are arranged side by side so as to extend in the vertical direction in the heat exchange exhaust part 6. Even if the drain generated by heat exchange adheres to the surface of each heat receiving pipe 31, this drain falls smoothly without stagnation on the surface of the heat receiving pipe 31.

  One end side of each heat receiving pipe 31 is connected to a water inlet side header 32 provided on the upper end side of the heat exchange exhaust part 6, and the other end side is provided on a water outlet side header 33 provided on the lower end side of the heat exchange exhaust part 6. It is connected to the. Therefore, the hot water supplied to the secondary heat exchanger 30 first flows into the water inlet side header 32, then flows divided into each heat receiving pipe 31 connected thereto, and then gathers at the water outlet side header 33 and flows out to the outside. Will be.

  The water inlet side header 32 is provided with a secondary water inlet 35 and is connected to a water supply source (not shown) via a pipe (not shown). On the other hand, the lower end side of each heat receiving pipe 31 is connected to the water discharge side header 33. The water outlet header 33 is provided with a secondary water outlet 37. The secondary water outlet 37 is connected to the connection port 16 of the primary heat exchanger 20 via a pipe 38. Moreover, the secondary water inlet 35 and the secondary water outlet 37 are the arrangement | positioning which protruded outside from the outer wall member 6a.

  As shown in FIGS. 2 and 8, the heat receiving tube 31 has a meandering shape that is folded back into a substantially “<” shape in the middle. As a result, the heat receiving pipe 31 has a plurality of crossing portions 31a that cross the heat exchange exhaust portion 6 in the middle, and has a folded portion 31b between the crossing portions 31a. The transverse part 31a is arranged with a downward slope. Moreover, the crossing part 31a differs in the direction of the descending gradient from the crossing part 31a arrange | positioned in the position adjacent to an up-down direction. Specifically, as shown in FIG. 2, the crossing portion 31 a located on the uppermost side (upstream side) of the heat receiving pipe 31 is lowered toward the back side (right side in FIG. 2) of the combustion apparatus 1. It is arranged with a downward slope so as to incline. Therefore, even if drain adheres to the surface of the heat receiving tube 31 due to heat exchange, it flows along the surface of the transverse portion 31a and falls, so that the drain adheres to the surface of the heat receiving tube 31 over a long period of time. And can be collected smoothly.

  On the other hand, the crossing part 31a in the position adjacent to the lower part (downstream side) of this crossing part (uppermost crossing part) 31a is connected to the crossing part 31a via the turn-up part 31b, and the front of the combustion apparatus 1 It is arranged with a downward slope so as to incline downward toward the side (left side in FIG. 2). As described above, the heat receiving pipe 31 is provided with the transverse portion 31a and the folded portion 31b successively one after another, and a series of flow paths is formed. Therefore, when hot water (heat medium) is supplied to the heat receiving pipe 31, the hot water gradually flows downwardly while flowing in a zigzag manner between the front side and the back side of the combustion device 1. It goes to the side header 33.

  As shown in FIGS. 2 and 8, the secondary heat exchanger 30 has a plurality of (six in this embodiment) heat receiving tubes 31 that are bent as described above, and are arranged so as to be adjacent in parallel. Each of the heat receiving tubes 31 is in a vertical orientation and is accommodated in the heat exchange exhaust unit 6. The heat receiving pipes 31 are arranged side by side in the heat exchanger section 6 in the width direction of the combustion device 1 (left and right in the state shown in FIG. 1). Further, each heat receiving pipe 31 is arranged so that the crossing portion 31a extends in the depth direction of the combustion apparatus 1 (direction intersecting the paper surface in the state shown in FIG. 1).

That is, in the combustion apparatus 1 of the present embodiment, the secondary heat exchanger 30 is connected between the crossing portions 31a crossing the opening region of the heat exchange exhaust portion 6 by the folded portion 31b, and the heat exchange exhaust portion 6 is formed. Since the heat receiving pipe 31 that reciprocates in a zigzag manner is adopted, the heat transfer area is sufficiently large while being compact in the vertical direction.
In addition, since the heat receiving pipe 31 is bent into a substantially “<” shape at a folded portion 31 b provided in the middle, the secondary heat exchanger 30 is configured such that the heat receiving pipe 31 is used as a combustion gas. Even if it is exposed to a high temperature, the strain generated as the heat receiving pipe 31 expands can be relaxed so as to be minimized.

  Moreover, in the heat exchanger chamber 17, as shown in FIG. 2, the restriction | limiting board 4 is provided in three places between the crossing parts 31a adjacent to the upper and lower sides (FIG. 2). Specifically, in the heat exchange chamber 17, the vicinity of the first folding part 31b, the vicinity of the fifth folding part 31b on the downstream side in the flow direction of the combustion gas, and the third folding part on the downstream side from there. It is fixed to the outer wall member 6a or the partition member 6h near 31b. That is, the restriction plates 4 are arranged in a staggered manner in the heat exchange chamber 17 in the flow direction of the combustion gas.

  As shown in FIGS. 2 and 9, the regulation plate 4 has a flat surface portion 39 and a curved surface portion 40. The curved surface portion 40 is obtained by bending a square plate member into an arc shape, and a planar portion 39 is disposed on one linear side 40 a of the curved surface portion 40 so as to be integrated with the planar portion 39. It is joined. Note that the thickness and width of the flat surface portion 39 are the same as the thickness and width of the curved surface portion 40.

As shown in FIGS. 2 and 9, the restricting plate 4 is such that the side facing the side 40a of the curved surface portion 40 is fixed to the outer wall member 6a or the partition member 6h. It arrange | positions in the direction which cross | intersects with respect to the gas flow direction. Specifically, in a state where the regulation plate 4 is fixed, the flat surface portion 39 is inclined upward from the curved surface portion 40 toward the protruding direction.
Further, the flat portion 39 is provided with a ventilation portion 34 on the side 39 a side joined to the curved surface portion 40. The ventilation part 34 is a rectangular slit (opening), and is a long hole extending in the length direction of the side 39a in a fixed state. Specifically, the ventilation portion 34 is a rectangular long hole that is long in the arrangement direction of the plurality of heat receiving tubes 31.

  The ventilation portion 34 is disposed in the vicinity of the connection portion between the transverse portion 31a and the folded portion 31b of the heat receiving pipe 31 in a state where the regulation plate 4 is fixed to the outer wall member 6a or the partition member 6h. More specifically, the ventilation part 34 is located in the vertical projection region on the side of the transverse part 31a in the vicinity of the connection part. In other words, the ventilation portion 34 is disposed at a predetermined distance from a gap formed between the folded portion 31b and the outer wall member 6a or the partition member 6h. For this reason, according to the combustion apparatus 1 of the present embodiment, the combustion gas that has passed through the ventilation portion 34 is prevented from concentrating and passing through the gap, so that the thermal efficiency does not decrease.

  In the combustion apparatus 1 of the present embodiment, the restriction plate 4 disposed on the most downstream side in the flow direction of the combustion gas in the heat exchange chamber 17 is slightly below the communication hole 6i communicating with the exhaust passage 18 (FIG. 2). ) Is recommended to be positioned. As a result, the drain that has fallen on the restriction plate 4 is prevented from flowing into the exhaust flow path portion 18 along the inclination of the restriction plate 4.

  Therefore, the combustion gas introduced into the heat exchange chamber 17 changes its flow direction by the restriction plate 4 and temporarily stays there, so that the exhaust time is delayed. Thereby, the combustion apparatus 1 of the present embodiment can improve the thermal efficiency because the combustion gas and the hot water flowing through the heat receiving pipe 31 are further heat exchanged by the amount of the exhaust time being delayed. Further, due to the curved surface shape of the curved surface portion 40 of the regulating plate 4 and the inclination of the flat surface portion 39, the exhaust of the combustion gas is smoothly delayed while flowing downstream, so that an excessive load is not applied to the blower 11. That is, even if the secondary heat exchanger 30 is provided with the restriction plate 4, it is not necessary to increase the rotational speed of the blower 11, so that it is possible to suppress an increase in noise and running cost during operation. Furthermore, no trouble is caused in the combustion state of the combustion section 2.

  In the present embodiment, as described above, since the ventilation portion 34 is provided in the flat portion 39, a part of the combustion gas that collides with the flat portion 39 flows downstream through the ventilation portion 34. Thereby, the combustion gas can be circulated in the vicinity of the upper surface (FIG. 2) side of the restriction plate 4, so that heat exchange can be performed in the heat receiving pipe 31 located in the vicinity of the upper surface side of the restriction plate 4. Therefore, according to the combustion apparatus 1 of the present embodiment, the combustion gas can be circulated even in a place where the combustion gas does not easily flow in the heat exchange chamber 17. It is possible to improve. In addition, since the ventilation part 34 allows a part of combustion gas which collides with the control board 4 to pass downstream, it can prevent that the ventilation resistance of combustion gas raises remarkably.

Then, operation | movement of the combustion apparatus 1 is demonstrated in detail focusing on the flow of combustion gas or hot water.
When the combustion apparatus 1 detects that hot water has been supplied from an external water supply source to the secondary heat exchanger 30 by a flow sensor or the like (not shown), the combustion unit 2 starts a combustion operation. The combustion gas generated with the combustion operation in the combustion section 2 flows downward in the combustion case 3 shown in FIG. Thereafter, the combustion gas passes through the exhaust collecting portion 5 provided on the bottom side of the combustion apparatus 1 and flows into the convex space 5 a of the exhaust collecting portion 5. Then, the combustion gas passes through the inlet 6e provided on the side surface of the heat exchange exhaust part 6 in the horizontal direction and escapes to the heat exchange exhaust part 6 side. The combustion gas that has flowed into the heat exchange exhaust section 6 in this way has its traveling direction changed upward in the upstream region 6y of the heat exchange chamber 17, and the secondary heat exchanger 30 provided in the heat exchange region 6x. After flowing between the heat receiving pipes 31, the downstream region 6z is reached, and the traveling direction is further changed.

  Specifically, the flow direction of the combustion gas introduced from the introduction port 6e is changed by the restriction plates 4 provided at three locations, and the exhaust time is delayed to reach the downstream region 6z. Furthermore, a part of the combustion gas passes through the ventilation portion 34 of the regulation plate 4, so that heat exchange is possible in the heat receiving pipe 31 (a portion where the combustion gas is relatively difficult to flow) located near the upper portion of the ventilation portion 34. That is, according to the combustion apparatus 1 of the present embodiment, the time for exchanging the heat of the combustion gas and the hot water is extended by the amount of the exhaust time of the combustion gas delayed by the flat portion 39, and the remaining combustion Since the gas flows to a place where it is difficult for the gas to flow in through the ventilation portion 34, the thermal efficiency can be further improved.

  Then, the combustion gas whose direction has been changed in the downstream region 6z of the heat exchange chamber 17 passes through the communication port 6i in the horizontal direction and escapes to the exhaust flow path portion 18 side. As shown in FIG. 2, the combustion gas that has flowed into the exhaust flow path 18 in this way is immediately turned downward and passes through the lower flow path forming part 18s. And if the combustion gas which passed the downward flow path formation part 18s reaches a lower end part, the advancing direction will be changed. That is, it passes through the communication port 6j in the horizontal direction and exits to the upper flow path forming portion 18t side. Thereafter, the combustion gas changes its traveling direction upward and passes through the upper flow path forming portion 18t. Then, the combustion gas that has passed through the upper flow path forming portion 18t reaches the upper end, passes through the communication port 6k vertically upward, and escapes to the conversion flow path forming member 19 side. The combustion gas that has passed through the exhaust flow path portion 18 has its traveling direction changed in the horizontal direction, and flows through the conversion flow path forming member 19 toward the exhaust port 6d. Then, the combustion gas passes through the exhaust port 6 d in a direction intersecting with the direction in which the combustion gas flows through the heat exchange chamber 17. That is, the combustion gas passes through the exhaust port 6d in the horizontal direction, not upward or downward, and is exhausted to the outside.

  On the other hand, the hot water supplied from the outside flows into each of a plurality (six in the illustrated state) of the heat receiving pipes 31 connected thereto via the water inlet header 32 of the secondary heat exchanger 30. The hot water that has flowed into each heat receiving pipe 31 passes through the zigzag channel formed so as to go back and forth between the front side and the back side of the combustion device 1 by repeating the crossing part 31a and the turning part 31b. It flows toward. Since the flow of hot water in the heat receiving pipe 31 flows from the upper side to the lower side as a whole, it flows upward in the heat exchange chamber 17 and further flows in a meandering manner with the combustion gas flowing in a meandering manner by the restriction plate 4. There is a relationship. Therefore, the hot water flowing through each heat receiving pipe 31 flows toward the water discharge side header 33 provided on the lower side of the heat exchange exhaust part 6 while exchanging heat efficiently with the combustion gas.

  Here, when heat is exchanged in the secondary heat exchanger 30 as described above, the latent heat contained in the combustion gas flowing in the heat exchange exhaust section 6 is heated in each heat receiving pipe 31. To be recovered. Along with this, moisture contained in the combustion gas is condensed, and drain adheres to the surface of the heat receiving pipe 31 of the secondary heat exchanger 30. Then, when the drain aggregates and grows to such an extent that it cannot resist gravity, the aggregated drain falls downward.

  Here, as described above, in the combustion apparatus 1 of the present embodiment, the inlet 6e of the heat exchange exhaust unit 6 is provided on the side surface of the heat exchange exhaust unit 6, and the bottom of the heat exchange chamber 17 receives drain. It is set as the saucer part 17a. Further, the combustion apparatus 1 can guide the drain to the neutralizer 7 via the pipe 48 connected to the drain discharge port 47 from the tray part 17a. Further, a weir portion 17b is provided in which the edge portion on the inlet 6e side of the tray portion 17a is erected upward. Therefore, even if the drain falls from the secondary heat exchanger 30 to the tray 17a, the drain does not flow into the exhaust collecting portion 5 located on the upstream side in the flow direction of the combustion gas via the inlet 6e, and the drain discharge It is discharged toward the neutralizer 7 through the system and neutralized.

Further, as described above, most of the water vapor of the combustion gas is generated as a drain by heat exchange with the secondary heat exchanger 30, so that the combustion gas that has passed through the secondary heat exchanger 30 becomes a dry gas. The combustion gas that has passed through the heat exchange chamber 17 hardly generates water droplets inside the exhaust flow path portion 18. Thereby, it is suppressed that the inside of the exhaust passage 18 is wetted by the drain and corrodes due to the oxidizing action of the drain.
And the combustion gas which passed the exhaust flow path part 18 is changed in the advancing direction, passes the conversion flow path formation part 19, and is discharged | emitted outside.

In the above-described embodiment, a configuration in which the flat surface portion 39 has the one rectangular ventilation portion 34 is shown. However, the present invention is not limited to this, and the heat receiving tube 31 is attached to the heat exchange chamber 17. Any shape can be used as long as it is long and long in the arrangement direction.
For example, as shown in FIGS. 10 to 12, the ventilation part is an elliptical ventilation part 34 a, a rectangular slit ventilation part 34 b arranged in a row, or an “S” -shaped type. The ventilation portion 34c having a curve may be used.

In the above embodiment, the ventilation portion 34 has a configuration of a series of one long hole shape, but the present invention is not limited to this, and the ventilation portion is formed by an assembly of a plurality of holes 36. It doesn't matter.
For example, the ventilation portion is an aggregate of square holes 36a as shown in FIG. 13 (a), an aggregate of circular holes 36b as shown in FIG. 13 (b), Although not shown, an aggregate in which the holes 36a and 36b are mixed may be used. The holes 36 a and 36 b are preferably arranged one by one with respect to one heat receiving pipe 31. Thereby, combustion gas can be made to flow through each heat receiving pipe 31 without unevenness.

  In the above embodiment, the configuration in which the ventilation portion 34 is formed only by the opening is shown, but the present invention is not limited to this, and the combustion gas is easily vented as shown in FIGS. 14 (a) and 14 (b). The guide portion 41 may be provided so as to be introduced into the portion 34. By doing so, the combustion gas can easily flow into the ventilation portion 34.

  In the above-described embodiment, the configuration in which the ventilation portion 34 has an opening shape is shown. However, the present invention is not limited to this, and as shown in FIG. 15, the ventilation portion 34d has a ventilation portion 34d having a notch shape. It doesn't matter. Thereby, substantially the same effect as the above-described embodiment can be obtained.

  In the above-described embodiment, the configuration in which the ventilation portion 34 is provided in the flat portion 39 is shown, but the present invention is not limited to this, and the configuration in which the ventilation portion 34 is provided in the curved surface portion may be used. Even in this case, since it is preferable to arrange the ventilation portion 34 in the vicinity of the connection portion between the transverse portion 31a and the folded portion 31b of the heat receiving tube 31, it is recommended that the curved surface portion be longer than that in the above embodiment.

  In the said embodiment, although the structure which attached the restriction | limiting board 4 to the heat exchange chamber 17 was shown, this invention is not limited to this, Even if it is the structure attached to 1, 2, or 4 or more places. I do not care. For example, when it is mounted in the vicinity of all the folded portions 31b except for the uppermost portion (in this embodiment, 10 locations), the flow of hot water and the flow of combustion gas become counterflow at almost all positions in the heat exchange chamber 17. Thus, a configuration with better thermal efficiency can be obtained.

  In the above-described embodiment, the configuration in which the heat receiving pipes 31 having substantially the same meandering shape are arranged in parallel is shown. However, the present invention is not limited to this, and includes the crossing part 31a and the folded part 31b, A plurality of heat receiving tubes 31 having a shape may be arranged in parallel.

  In the above embodiment, the configuration in which the restriction plate 4 is mounted on the latent heat recovery type heat exchanger (secondary heat exchanger) 30 is shown, but the present invention is not limited to this, and the sensible heat recovery type heat exchange is performed. It may be configured to be mounted on the container 20. That is, as shown in the above embodiment, any heat exchanger can be used as long as it is a heat exchanger using the heat receiving pipe 31 having a meandering shape (meandering shape formed by the crossing part 31a and the folded part 31b). It does not matter.

  The combustion apparatus 1 shown in the above embodiment includes the so-called reverse combustion type combustion unit 2, but the present invention is not limited to this, and the combustion unit 2 flames upward. It may be of the type that forms. In addition, the above-described combustion unit 2 sprays and burns liquid fuel. Instead, for example, a combustion apparatus that vaporizes liquid fuel, such as a conventionally known vaporization type combustion apparatus, burns. Any combustion form such as a type may be employed.

1 Combustion device 2 Combustion section (combustion means)
4 regulating plate 5 exhaust collecting part 6 heat exchange exhaust part 6a outer wall member (housing part, side wall)
20 Primary heat exchanger 30 Secondary heat exchanger 31 Heat receiving pipe 31a Crossing part 31b Folding part 34, 34a, 34b, 34c, 34d Ventilation part 36 Hole 39 Flat part 40 Curved part

Claims (3)

A heat exchanger that has a casing part into which combustion gas is introduced, and in which the hot water or heat medium recovers heat of the combustion gas and exchanges heat.
A plurality of heat receiving pipes through which hot water or a heat medium flows, and a regulation plate that regulates the flow direction of the combustion gas are provided in the housing part,
The plurality of heat receiving tubes are arranged adjacent to each other in parallel,
The heat receiving pipe includes a plurality of crossing portions that cross the flow direction of the combustion gas, and a turn-back portion that connects between a crossing portion located on the upstream side in the flow direction of the hot water or the heat medium and a crossing portion located on the downstream side. The folded portion can fold the flow of hot water or heat medium supplied from the upstream crossing portion and supply the flow to the downstream crossing portion,
The regulating plate may have a vent to allow passage of a portion of the combustion gases,
The ventilation portion is disposed in the vicinity of the connection portion between the crossing portion and the folded portion of the heat receiving pipe and upstream of the heat receiving pipe in the flow direction of the combustion gas,
A long hole shape that is long in the arrangement direction of the heat receiving tubes, or an assembly of a plurality of holes arranged in the arrangement direction of the heat receiving tubes,
The restriction plate is a plate-shaped member having at least a flat surface portion and a curved surface portion,
The flat portion is provided with the ventilation portion and is disposed at an angle intersecting with the flow direction of the combustion gas, and is inclined upward from the curved surface portion toward the protruding direction,
The curved surface portion is fixed to the inner wall surface of the housing portion, and extends across a gap formed between the inner wall surface of the housing portion and the folded portion,
A heat exchanger characterized in that the combustion gas that has passed through the ventilation section is caused to flow through a downstream heat receiving pipe . The regulating plate is provided in plurality, the heat exchanger according to claim 1, characterized in that the are in the flow direction of the combustion gas on the side walls of the casing are fixed arranged in a staggered manner. Combustion means for burning fuel;
A combustion gas passage through which the combustion gas generated along with the combustion operation in the combustion means flows downward;
An exhaust collecting portion that exists downstream in the flow direction of the combustion gas with respect to the combustion gas passage, receives and passes the combustion gas that has passed through the combustion gas passage, and changes the flow direction upward;
A heat exchange exhaust that can receive and pass the combustion gas sent from the exhaust assembly, and flow upwards;
A primary heat exchanger capable of heating hot water or a heat medium by heat exchange with the combustion gas flowing through the combustion gas passage;
A secondary heat exchanger disposed in the heat exchange exhaust section,
Combustion apparatus wherein the secondary heat exchanger is a heat exchanger according to claim 1 or 2.

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