JP2019060524A - Heat exchanger and water heating system having the same - Google Patents

Abstract

To provide a heat exchanger capable of efficiently and properly making progress the heating gas after heat recovery in a substantially horizontal direction even when the heating gas such as combustion gas is progressing upwardly or downwardly.SOLUTION: A heat exchanger HE having a plurality of plate-like fins 8 joined to a heat transfer pipe 7 and aligned via a plurality of gaps 6 in the substantially horizontal direction, in which one of a lower part and an upper part of the plurality of gaps 6 is to be a first gap opening 6a capable of making progress the heating gas into the plurality of gaps 6. In the plurality of fins 8, gap closing parts Ba and Bb are provided for closing the other of the lower part and the upper part of the plurality of gaps 6 while in the plurality of gaps 6, a second gap opening 6b, which is open in the substantially horizontal direction, is provided. At least part of the heating gas t has entered the plurality of gaps 6 from the first gap opening 6a can pass through the second opening 6b after colliding with the gap closing parts Ba and Bb.SELECTED DRAWING: Figure 1

Description

  BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a heat exchanger and a hot water system such as a water heater including the heat exchanger.

As a specific example of a hot water apparatus configured as a hot water supply apparatus, there is an apparatus described in Patent Document 1 and this is shown in FIG.
In a hot water system We shown in the same figure, a heat exchanger H including a heat transfer pipe 7e and a plurality of plate-like fins 8e joined to the heat transfer pipe 7e is disposed at the top in a case 3e in which the burner 1e is accommodated The heat exchanger H recovers heat from the combustion gas generated by the burner 1e. On the other hand, a narrow portion 30e whose front and rear width is narrowed is provided at the upper portion of the case 3e, and an exhaust port 36 opening forward is provided at the front wall portion of the case 3e. At the lower part of the part, a shelf-like wall 30b is provided. On the shelf-shaped wall portion 30b, an exhaust cylinder 38 in which a silencer 38a is incorporated is disposed, and the combustion gas having passed through the exhaust port 36 is sent to the exhaust cylinder 38.

  However, in the above-mentioned prior art, as will be described next, there is still room for improvement.

  That is, in the above-described hot water apparatus We, it is necessary to discharge the combustion gas whose heat has been recovered by the heat exchanger H from the exhaust port 36 in a substantially horizontal direction. However, the heat exchanger H itself does not have the function of guiding the combustion gas advancing from below to the exhaust port 36 and then advancing it in a substantially horizontal direction, and the combustion gas is a gap between the plurality of fins 8e. It is supposed to pass upward as it is. For this reason, the combustion gas which has passed through the gap is guided once to the exhaust port 36 after colliding with the shelf wall 30 b of the case 3 e and the upper wall 30 c of the narrow portion 30. In this case, when a relatively large amount of heat remains in the combustion gas, the shelf-shaped wall portion 30b and the upper wall portion 30c of the case 3e are unnecessarily heated. Also, in recent years, a hot water apparatus of a type equipped with a secondary heat exchanger for recovering latent heat in place of the exhaust cylinder 38 is widely spread, but in such a hot water apparatus, case 3e The heat exchange efficiency is lowered by the amount of heat absorption from the combustion gas by the shelf wall portion 30b and the upper wall portion 30c.

Japanese Patent Laid-Open No. 2000-161790

  The present invention has been conceived under the circumstances as described above, and even if the heating gas such as the combustion gas proceeds upward or downward, the heating gas after heat recovery is substantially It is an object of the present invention to provide a heat exchanger that can be advanced efficiently and appropriately in the horizontal direction, and a hot water apparatus provided with the same.

  In order to solve the above problems, the present invention takes the following technical measures.

The heat exchanger provided by the first aspect of the present invention includes a plurality of plate-like fins joined to the heat transfer tube and arranged substantially horizontally along a plurality of gaps, and the plurality of gaps are provided. One of the lower and upper portions of the first is capable of causing the heating gas to enter the plurality of gaps;
The heat exchanger, wherein the plurality of fins are provided with a gap closing portion for closing the other of the lower portion or the upper portion of the plurality of gaps, and the plurality of fins are provided in the plurality of gaps A second gap opening is provided that is open substantially in the horizontal direction, and at least a portion of the heating gas that has entered the plurality of gaps from the first gap opening is the gap closing part. And the second gap opening portion can pass through.

According to such a configuration, the following effects can be obtained.
That is, when the heating gas such as the combustion gas travels upward or downward with respect to the heat exchanger and travels from the first gap opening to the gap between the plurality of fins, at least one of the heating gases Since the part subsequently collides with the gap closing part of the plurality of fins, it is prevented from passing the gap upward or downward as it is. Most of the heating gas which has caused the collision thereafter passes through the second gap opening in a substantially horizontal direction and flows out of the gap.
Thus, according to the present invention, it is possible to make the heating gas traveling upward or downward travel in a substantially horizontal direction by the heat exchanger itself. Therefore, it is most suitable for applications where the heating gas after heat recovery is exhausted in a substantially horizontal direction. When the heating gas passes through the gaps between the fins upward or downward as it is, the heating gas collides with the case surrounding the heat exchanger as described in the background art section, and this collision portion However, the present invention can eliminate such a disadvantage, although there is a disadvantage that the heat from the heating gas is absorbed by this portion. In addition, according to the present invention, it is possible to recover heat using the gap closing portion, which is more preferable in enhancing the heat exchange efficiency of the heat exchanger.

  In the present invention, preferably, the gap closing portion is constituted by a bent piece continuously connected to the upper edge or the lower edge of each of the plurality of fins.

  According to such a configuration, the gap closing portion can be provided without using a member separate from the fin, which is preferable in terms of reducing the manufacturing cost.

  A hot water system provided by the second aspect of the present invention includes a burner, a heat exchanger for recovering heat from combustion gases generated by the burner and heating water, and the heat exchanger. And a case provided with an air outlet opening forwardly or backwardly in the front wall portion or the rear wall portion, the water heater comprising the first heat exchanger of the present invention as the heat exchanger. A heat exchanger provided by a side surface is provided, and the second clearance opening of the heat exchanger is characterized by being provided opposite to the exhaust port.

  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, and the heat exchange efficiency of the hot water apparatus can be made excellent.

  In the present invention, preferably, a fan is provided for supplying combustion air to the burner, and in the case, the outer region of the gap closing portion of the heat exchanger is supplied with air from the fan. Thus, the air pressure chamber has a pressure higher than that in the gap between the plurality of fins.

  According to such a configuration, even if a minute gap exists in the gap closing portion, the combustion gas in the gap is the air pressure chamber (outside area of the gap closing portion) due to the pressure difference between the air pressure chamber and the gap. To prevent leakage.

In the present invention, preferably, a secondary heat exchanger for hot water heating, which is configured separately from the heat exchanger, is preferably provided so that the heat exchanger is a primary heat exchanger, In the upper portion of the case, a narrow portion whose front and rear width is smaller than that of the other portion of the case, and a front side or a rear side of a lower portion of the narrow portion are continuously provided. A shelf-like wall to be mounted is provided, and the exhaust port is provided in the front wall or the rear wall of the narrow portion, and the plurality of fins are advanced upward from the burner And the combustion gas which passed the said exhaust port is comprised so that the said secondary heat exchanger may be supplied.

  According to such a configuration, of course, the heat exchange efficiency can be enhanced by utilizing the secondary heat exchanger, and in addition, to guide the combustion gas having passed through the primary heat exchanger to the secondary heat exchanger It is not necessary to use a dedicated member (member referred to as an exhaust collecting cylinder) as the means of.

  In the present invention, preferably, each of the fins is connected to a first region located below the shelf-like wall and extending in the front-rear direction, one end of the first region, and the inside of the narrow portion. And a second region located on the side of the vehicle.

  According to such a configuration, each fin can be formed in a wide area in accordance with the internal shape of the case. Therefore, it is more preferable to increase the heat exchange efficiency.

  In the present invention, preferably, the heat transfer tube has a plurality of straight tube parts penetrating and joined to the first region and the second region, and among the plurality of straight tube parts, The plurality of straight tubular body parts penetrating in the first region are arranged to be higher in height as they approach the exhaust port.

  According to such a configuration, it is possible to efficiently cause the combustion gas advancing toward the exhaust port in the case to act on the plurality of straight tubular body parts penetrating the first region. This can further enhance the heat exchange efficiency.

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

It is a schematic sectional drawing which shows an example of the hot-water apparatus provided with the heat exchanger which concerns on this invention. (A) is IIa-IIa sectional drawing of FIG. 1, (b) is IIb-IIb sectional drawing of FIG. It is a principal part schematic perspective view of a hot-water apparatus shown in FIG. It is a principal part disassembled perspective view of a structure shown in FIG. (A) is a side view as a component figure of the fin used for the heat exchanger shown in FIG. 1, (b) is a side view of the state which divided | segmented the fin shown to (a). It is side surface sectional drawing which shows the other example of this invention. It is side surface sectional drawing which shows the other example of this invention. It is principal part sectional drawing which shows an example of a prior art.

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

  The water heater WH shown in FIG. 1 is configured as a water heater, and includes a burner 1 such as a gas burner, a fan 4 for supplying combustion air to the burner 1, and the burner 1 housed inside the lower portion. A case-like combustion chamber forming member 2 in which a chamber 29 is formed, a primary heat exchanger HE, a secondary heat exchanger 9, and a case 5 (unit case) are provided. The case 5 surrounds the combustion chamber forming member 2 and the primary heat exchanger HE. Of the inside of the case 5, the outer region of the combustion chamber forming member 2 and the primary heat exchanger HE is an air pressure chamber 59 described later.

  As shown in FIG. 3 and FIG. 4, the primary heat exchanger HE includes a meandering heat transfer tube 7 and a plurality of plate-shaped fins 8 joined to the heat transfer tube 7 in a side view substantially L-shape. (FIG. 3 shows the fins 8 partially omitted). The plurality of fins 8 are arranged at predetermined intervals in the longitudinal direction of the straight tube portion 70 of the heat transfer tube 7.

  As shown in FIG. 5, the fin 8 is configured by combining the first and second fin plates 8 a and 8 b divided through the dividing line PL. The first and second fin plates 8a and 8b are provided with a burring portion 82 having a substantially semicircular arc-shaped cross section forming a recess 80 in which a portion of the heat transfer tube 7 is fitted. According to such a configuration, attachment of the fins 8 to the heat transfer tube 7 can be achieved by sandwiching the heat transfer tube 7 by the burring portions 82 of the first and second fin plates 8a and 8b. Therefore, the attachment work of the fins 8 to the heat transfer tube 7 can be facilitated.

  Each fin 8 is substantially L-shaped in a side view so as to correspond to the shape of the upper portion of the case 5. More specifically, as shown in FIG. 1, the upper portion of case 5 is narrower than the lower portion of case 5 as a means for easily connecting secondary heat exchanger 9. It has a portion 50, an exhaust port 56 provided in the front wall portion 50a, and a shelf-like wall portion 50b continuously provided in the lower portion of the front wall portion 50a. The secondary heat exchanger 9 is mounted on the shelf wall 50 b, and the combustion gas that has passed through the primary heat exchanger HE is fed into the secondary heat exchanger 9 from the exhaust port 56. Corresponding to such a configuration, each fin 8 is located below the shelf-like wall portion 50b and extends in the front-rear direction, a first region R1, and a rear end of the first region R1 and a narrow portion 50. And the second region R2 located inside of the above, and as described above, the side view shape is substantially L-shaped. The plurality of straight tube portions 70 of the heat transfer tube 7 are also provided in the corresponding array, and the position of the straight tube portion 70 penetrating the first region R1 is closer to the exhaust port 56, It is arranged to be high. This is effective in efficiently causing the combustion gas flowing obliquely upward toward the exhaust port 56 to act on the straight tubular portion 70 efficiently, and helps to increase the amount of heat recovery.

Each fin 8 is provided with bent pieces 81a and 81b obtained by bending the edge portion into a substantially horizontal shape, and these closed pieces 81a and 81b form gap closing parts Ba and Bb.
More specifically, the bent piece 81a is provided at the upper edge of the first region R1 of the fin 8, and as shown in FIG. 2A, the plurality of bent pieces 81a adjacent to each other are They are in contact with each other so that no gap is generated between them. The bent pieces 81b are provided in series from the upper edge to the rear edge of the second region R2 of the fin 8, and as shown in FIG. 2 (b), a plurality of adjacent bent pieces 81b are mutually adjacent. Are also in contact with one another such that no gap is created between them. These bent pieces 81 a and 81 b constitute gap closing portions Ba and Bb that close the upper portion of the gap 6 formed between the plurality of fins 8.

On the other hand, the lower part of the plurality of fins 8 and the portion facing the exhaust port 56 (the front edge of the second region R2) are not provided with the bent pieces as described above. The lower portion of the gap 6 is a first gap opening 6 a that allows the combustion gas to flow into the gap 6. Further, in the gap 6, a portion opposed to the exhaust port 56 is a second gap opening 6b which is opened in a substantially horizontal direction (front side).
As a result, most of the combustion gas that has progressed from below toward the primary heat exchanger HE enters the gap 6 between the fins 8, and then the gap closing portions Ba and Bb (folded pieces It is appropriately prevented from colliding with 81a and 81b) and passing the clearance 6 upward as it is. After colliding with the gap closing portions Ba and Bb, the combustion gas passes through the second gap opening 6b in a substantially horizontal direction, reaches the exhaust port 56, and flows into the secondary heat exchanger 9.
The secondary heat exchanger 9 is for recovering latent heat, and has a configuration in which a heat transfer pipe 91 is accommodated in a case 90. The combustion gas having passed through the exhaust port 56 advances into the case 90, and after the latent heat is recovered by the heat transfer pipe 91, the exhaust gas is exhausted to the outside from the exhaust port 92.

  As shown in FIG. 3 and FIG. 4, the upper part of the combustion chamber forming member 2 is provided with a plurality of concave portions 24 opened upward. On the other hand, in the heat transfer tube 7, the respective bases of the bend pipe 71 projecting outside the fins 8 (8 a) at both ends, the water inlet pipe part 72 a, and the hot water discharge pipe part 72 b are concave parts 24. Inserted into the As a result, the primary heat exchanger HE is supported on the top of the combustion chamber forming member 2. The lower side regions of the fins 8 (8a) at both ends and the left and right side wall portions 20a of the combustion chamber forming member 2 are in contact with each other so as to create a gap as little as possible. On the other hand, as shown in FIG. 1, the upper ends of the front wall 22 and the rear wall 20b of the combustion chamber forming member 2 are in contact with the bent pieces 81a and 81b of the fins 8, and combustion gas from these parts Is to prevent leakage.

  The combustion air supplied from the fan 4 to the inside of the case 5 is supplied to the installation area of the burner 1 through the vent 28 provided at the bottom of the combustion chamber forming member 2. Moreover, after being mixed with fuel gas by the path not shown, it is supplied in the burner 1. However, in addition to this, a part of the combustion air is configured to advance also to the gap region of the mutually facing wall portions of the combustion chamber forming member 2 and the case 5. As a result, in the case 5, the outer regions of the combustion chamber forming member 2 and the primary heat exchanger HE are air pressure chambers 59. The pressure P3 of the air pressure chamber 59 is higher than the pressure P1 of the combustion chamber 29 and the pressure P2 in the primary heat exchanger HE (the pressure in the gap 6 of the fin 8). Since the pressure P1, P2 in the combustion chamber 29 and the primary heat exchanger HE has a large air flow resistance due to the air holes 28 and the burner 1, the air is supplied from the common fan 4, It is possible to generate a pressure difference as described above. As means for making the pressure P3 of the air pressure chamber 59 higher than the pressures P1 and P2, an additional fan different from the fan 4 is further provided, and the air pressure chamber 59 described above from the additional fan is provided. It is also possible to employ means for supplying air.

  Next, the operation of the above-described water heater WH will be described.

  First, in the primary heat exchanger HE, as described above, when the combustion gas enters the gap 6 of the fin 8 upward from below, it collides with the gap closing portions Ba and Bb, and then this gap closing portion It is guided to the 2nd clearance opening 6b which opposes the exhaust port 56 by Ba and Bb. Then, the combustion gas travels in the substantially horizontal direction (forward) through the second gap opening 6 b, passes through the exhaust port 56, and flows into the secondary heat exchanger 9. Therefore, the combustion gas is smoothly supplied to the secondary heat exchanger 9. Since the combustion gas does not pass above the fins 8 and collide with the shelf wall 50 b or the upper wall of the narrow portion 50, those portions are heated excessively or remain in the combustion gas. It is also possible to reduce waste such that much of the heat to be absorbed is absorbed by the case 5. Further, since the combustion gas collides with the gap closing portions Ba and Bb, it is possible to increase the heat recovery amount by the gap closing portions Ba and Bb. Because of this, it is possible to make the water heater WH excellent in heat exchange efficiency.

Since the outer region of the primary heat exchanger HE is an air pressure chamber 59 of a pressure P3 higher than the pressure P2 in the primary heat exchanger HE, the outer region of the primary heat exchanger HE (air Leakage of the combustion gas into the pressure chamber 59) is prevented. For example, even if a contact failure occurs between the bent pieces 81a of the fins 8 or between the bent pieces 81b, if the contact failure is mild, the heat passes through this portion and the primary heat It is possible to prevent the combustion gases from flowing out into the outer region of the exchanger HE. Further, since the air pressure chamber 59 is formed not only in the outer region of the primary heat exchanger HE but also in the outer region of the combustion chamber forming member 2, the combustion chamber forming member 2 and the primary heat exchanger HE Leakage of combustion gas from the connection portion of the fuel cell and the attachment portion of various parts to the combustion chamber forming member 2 is also appropriately prevented. This is preferable to reduce the need for using expensive seal members and to reduce the manufacturing cost.

  6 and 7 show another embodiment of the present invention. In these figures, elements which are the same as or similar to those of the above-described embodiment are denoted by the same reference numerals as those of the above-described embodiment, and redundant description will be omitted.

In the heat exchanger HE1 of the embodiment shown in FIG. 6, the fins 8 have a rectangular shape in a side view, and the upper side of the gap 6 between the plurality of fins 8 has progressed upward from below. A gap closing portion B where the combustion gas collides is provided. A second gap opening 6b is provided on the front side (left side in the figure) of the gap 6, and the combustion gas is directed from the second gap opening 6b to the outside of the gap 6 in a substantially horizontal direction (forward) It is possible to spill it out. Therefore, the intended action of the present invention can be obtained.
As understood from the present embodiment, according to the present invention, the overall side view shape of the fin 8 is not limited to the substantially L shape, and can be formed into various shapes.

In the heat exchanger HE2 of the embodiment shown in FIG. 7, the gap closing portions Ba and Bb are configured using thin metal members 88a and 88b separate from the fins 8.
Also in this embodiment, it is possible to obtain the intended effect of the present invention. As understood from the present embodiment, the gap closing portion may be either provided integrally with the fin or provided as a separate member.

  The present invention is not limited to the contents of the embodiments described above. The specific configuration of each part of the heat exchanger and the water heater according to the present invention can be variously designed and changed within the intended scope of the present invention.

  In the above-mentioned embodiment, although the example which combustion gas (gas for heating) advances upward from the lower part of a heat exchanger (primary heat exchanger) was shown, conversely, combustion gas heat-exchanges The present invention can also be applied to the case of progressing downward from above the vessel. In this case, the configuration of each part of the fins in the above-described embodiment may be reversed up and down, and the gap closing part where the combustion gas collides is provided in the lower part of the gap between the fins. Become.

  In the embodiment described above, the outer region of the heat exchanger is an air pressure chamber having a pressure higher than that in the heat exchanger, but such a configuration may not necessarily be employed. Moreover, although the heat exchanger tube of the heat exchanger is directly held by the combustion chamber forming member, it is also not limited. For example, the heat exchanger may have a structure in which a heat transfer pipe is accommodated in a frame-like can, and the can and the combustion chamber forming member may be connected to each other.

  The hot-water apparatus which concerns on this invention can also be set as the structure which does not comprise a secondary heat exchanger. Moreover, it is not limited to a hot-water supply apparatus, For example, it is also possible to comprise as a hot-water apparatus for heating, a hot-water apparatus for snow melting, etc. As the heating gas in the present invention, gases other than the combustion gas generated using a burner can also be used.

WH water heater HE primary heat exchanger (heat exchanger)
Ba, Bb Clearance closing portion R1 First region (of fins)
R2 second region (of fins)
1 burner 4 fan 5 case 50 narrow portion 50a front wall portion (narrow portion)
50b shelf wall 56 exhaust port 59 air pressure chamber 6 gap (between fins)
6a first clearance opening 6b second clearance opening 7 heat transfer tube 8 fins 81a, 81b bent pieces (of fins)
9 Secondary heat exchanger

Claims (7)

And a plurality of plate-like fins joined to the heat transfer tube and arranged in a substantially horizontal direction with a plurality of gaps,
One of the lower and upper portions of the plurality of gaps is a heat exchanger, which is a first gap opening capable of causing a heating gas to enter the plurality of gaps,
The plurality of fins are provided with a gap closing portion that closes the other of the lower portion or the upper portion of the plurality of gaps, and the second gap opening portion is opened in the substantially horizontal direction in the plurality of gaps. Is provided,
At least a part of the heating gas that has entered the plurality of gaps from the first gap opening portion is configured to be able to pass through the second gap opening portion after colliding with the gap closing portion. Featuring a heat exchanger. The heat exchanger according to claim 1, wherein
The heat exchanger according to claim 1, wherein the gap closing portion is a bent piece continuously connected to the upper edge or the lower edge of each of the plurality of fins. With the burner,
A heat exchanger for recovering heat from the combustion gas generated by the burner and heating the hot and cold water;
A case which encloses the heat exchanger and is provided with a forward or backward opening in the front wall portion or the rear wall portion;
A water heater, and
The heat exchanger according to claim 1 or 2 is provided as the heat exchanger.
The second gap opening of the heat exchanger is provided to face the exhaust port. It is a hot-water apparatus of Claim 3, Comprising:
It has a fan that supplies combustion air to the burner,
In the case, the outer region of the gap closing portion of the heat exchanger is supplied with air from the fan, so that the air pressure chamber has a pressure higher than that in the gap between the plurality of fins. Being a hot water system. It is a hot-water apparatus of Claim 3 or 4, Comprising:
The apparatus further comprises a secondary heat exchanger for heating water and water, which is configured separately from the heat exchanger so that the heat exchanger is a primary heat exchanger,
In the upper portion of the case, a narrow portion whose front and rear width is smaller than that of the other portion of the case, and a front side or a rear side of a lower portion of the narrow portion are continuously provided. And a shelf-like wall portion to be mounted is provided,
The exhaust port is provided on the front wall or the rear wall of the narrow portion, and the combustion gas which travels upward from the burner and passes through the plurality of fins and the exhaust port is the secondary heat exchange Water heater, which is configured to be supplied to the It is a hot water apparatus of Claim 5, Comprising:
Each of the fins is located below the shelf-like wall and extends in the longitudinal direction, and a second region connected to one end of the first region and located inside the narrow portion. It has a substantially L-shape in a side view, and has a water heater. It is a hot-water apparatus of Claim 6, Comprising:
The heat transfer tube has a plurality of straight tube parts penetrating and joined to the first area and the second area,
Among the plurality of straight tubular body portions, the plurality of straight tubular body portions penetrating to the first region are arranged such that the height becomes higher as approaching the exhaust port.

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