JP6666124B2 - Combustion device and water heater - Google Patents

Description

  The present invention relates to a combustion device used for a water heater and a water heater using the combustion device.

  BACKGROUND ART Conventionally, a combustion device having a burner and a heat exchanger that transfers heat of combustion of the burner to water has been widely used in a water heater or the like. As this combustion device, as disclosed in Patent Document 1, for example, a can body is divided into two combustion chambers by a partition member, and a heat exchanger and a burner connected to a hot water supply circuit are arranged in one combustion chamber. In addition, there is known an arrangement in which a heat exchanger and a burner connected to a bath circuit or the like are provided in the other combustion chamber. In each heat exchanger, a plurality of fins are arranged in parallel at a predetermined interval, and a plurality of heat transfer tubes penetrating these fin groups are arranged in a direction substantially perpendicular to the flow of combustion exhaust gas from the burner. .

JP 2013-11409 A

  In a combustion device in which two circuits are arranged side by side as in Patent Document 1, at the time of assembly, each heat exchanger is assembled after a partition member is attached to the can, or each heat exchanger is first connected to the can. After that, a temporary assembly is performed by inserting a partition member between the two heat exchangers, and after each is positioned, the procedure for performing the permanent fixing is performed. However, since the ends of the fans of both heat exchangers are in contact with the partition member over substantially the entire length, the heat exchanger and the partition member can be contacted with each other by contact between the fin and the partition member in any case. The temporary assembly was difficult, and the assembly was troublesome.

  Therefore, an object of the present invention is to provide a combustion device and a water heater in which a temporary assembly of two heat exchangers and a partition member can be facilitated and the assembly can be performed smoothly.

In order to achieve the above object, the invention according to claim 1 is provided in a can body, a first combustion chamber and a second combustion chamber partitioned by a partition member in the can body, and the first combustion chamber. A first heat exchanger having a plurality of fins and a plurality of heat transfer tubes penetrating the fins, a first burner disposed below the first heat exchanger, and a second burner disposed in the second combustion chamber and penetrating the plurality of fins and the fins Combustion comprising a plurality of heat transfer tubes, a second heat exchanger having a smaller amount of water flow than the first heat exchanger, and a second burner disposed below the second heat exchanger and having a smaller amount of heat than the first burner. A device,
The first heat exchanger and the second heat exchanger are housed in the respective combustion chambers in a state where a part of the end of the fin on the partition member side is in contact with the partition member, and the fin of the first heat exchanger is The position where a part of the end abuts on the partition member and the position where a part of the fin end of the second heat exchanger abuts on the partition member are vertically displaced from each other , and the first heat exchanger and the second heat exchanger are shifted from each other . 2 It is characterized in that they do not overlap with each other in the direction of juxtaposition with the heat exchanger .
According to a second aspect of the present invention, in the configuration of the first aspect, the fins of the first heat exchanger are formed to have a smaller width in the vertical direction than the fins of the second heat exchanger, and the first heat exchanger. The upper end of the fin is located above the upper end of the fin of the second heat exchanger.
In order to achieve the above object, an invention according to claim 3 is a water heater, which is provided with the combustion device according to claim 1 or 2.

According to the first and third aspects of the invention, the position where a part of the end of the fin in the first heat exchanger abuts on the partition member and the part of the end of the fin in the second heat exchanger are partitioned. By displacing the position in contact with the member in the vertical direction so as not to overlap each other in the direction in which the first heat exchanger and the second heat exchanger are arranged side by side , the two heat exchangers and the partition member And the assembling can be performed smoothly.
According to the second aspect of the present invention, in addition to the effect of the first aspect, the upper end of the fin of the first heat exchanger having a small width in the vertical direction is located above the upper end of the fin of the second heat exchanger. Since the first combustion chamber is located, the first combustion chamber is formed to be wider in the vertical direction than the second combustion chamber, and a large combustion space of the first burner having a high combustion capacity can be secured. Therefore, it leads to stable combustion.

It is sectional drawing which shows the combustion apparatus part of a water heater. FIG. 2 is a perspective view of a heat exchanger (fins are partially omitted). It is an enlarged view of a bath side heat exchanger part.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view showing a combustion device portion of a water heater. The water heater 1 includes a combustion device 2 in which a burner unit 3, a heat exchanger 4, and an exhaust can 5 are installed in this order from below in a casing (not shown). Accommodating. The inside of the combustion device 2 communicates by assembling the middle casing 7 of the heat exchanger 4 above the lower casing 6 of the burner unit 3 and assembling the upper casing 8 of the exhaust can 5 above the middle casing 7. A single can 2a is formed.

  First, in the burner unit 3, a first burner group 9 as a first burner and a second burner group 10 as a second burner are arranged side by side in the left-right direction. Each of the burner groups 9 and 10 is composed of a plurality of flat burners 11, 11... Having a flame hole formed on the upper end surface thereof arranged in the left-right direction. The primary air for combustion is supplied together with the gas through a nozzle (not shown) connected to the pipe. Here, the first burner group 9 is used for hot water supply, and the second burner group 10 is used for reheating a bath. The number of burners 11 of the first burner group 9 having a large capacity is set to be larger than that of the second burner group 10. ing.

  Next, the heat exchanger 4 includes a hot water supply side heat exchanger 13 as a first heat exchanger located above the first burner group 9 and a second heat exchanger located above the second burner group 10. And the bath-side heat exchanger 14 are arranged side by side in the left-right direction. First, the hot water supply side heat exchanger 13 includes a plurality of plate-like fins 15, 15,... Laminated at predetermined intervals in the front-rear direction (the direction perpendicular to the plane of FIG. 7 comprises a plurality of heat transfer tubes 16, 16,... As shown in FIG. 2, the ends of the heat transfer tubes 16, 16 are connected to each other by connecting tubes 17, 17 outside the middle casing 7 so as to be connected in a meandering manner. Each of the fins 15 has a horizontally elongated band-shaped cut-and-raised fin 18 located above the heat transfer tube 16 (downstream of the combustion exhaust) between the heat transfer tubes 16 and 16 adjacent to the left and right, and below the cut-and-raised fin 18. The cut-and-raised fins 19, which are shorter in left and right lengths than the cut-and-raised fins 18, are formed. A water supply pipe (not shown) is connected to an inlet 20 of the heat transfer pipe 16 of the hot water supply side heat exchanger 13, and a tapping pipe 22 is connected to an outlet 21 of the heat transfer pipe 16. A dropping pipe 23 connected to the bathtub is branched and connected to the tapping pipe 22.

  The bath-side heat exchanger 14 is also disposed inside the middle casing 7 through a plurality of plate-like fins 24, 24,... It is composed of three heat transfer tubes 25. The heat transfer tube 25 has a smaller diameter than the heat transfer tube 16 of the hot water supply side heat exchanger 13. The heat transfer tubes 25 are arranged such that the lower stage is located at the top of the triangle in two rows and the upper stage is located in one row when viewed from the front in the arrangement direction of the fins 24 (hereinafter, when distinguishing the heat transfer tubes 25, One is referred to as an upper heat transfer tube 25A and the lower two are referred to as lower heat transfer tubes 25B, 25B.) As shown in FIG. By doing so, they are connected in a meandering manner. A return pipe 28 from the bathtub is connected to the inlet 27 of the heat transfer tube 25 of the bath-side heat exchanger 14, and an outgoing pipe 30 to the bathtub is connected to the outlet 29 of the heat transfer tube 25. As shown in FIG. 3, the distance S between the upper heat transfer tube 25A and the lower heat transfer tube 25B is set to be smaller than the diameter R of the heat transfer tube 25, and the lower side of the upper heat transfer tube 25A in the fin 24 has an upper transfer tube 25A. A band-shaped heat receiving portion 31 that covers the lower portion of the heat tube 25A is formed, and the upper end of the lower heat transfer tube 25B has a height that overlaps the heat receiving portion 31 in the left-right direction.

  In each of the fins 24, three cut-and-raised fins 32 to 34 whose left and right lengths become shorter toward the lower side are arranged vertically at a predetermined interval on the left and right of the upper heat transfer tube 25A. Of the cut-and-raised fins 32 at the top, the inner end (upper heat transfer tube 25A side, hereinafter, with respect to the cut-and-raised fins 32-34, the upper heat transfer tube 25A side is referred to as inside and the opposite side is referred to as outside), the end 32a is at the top. The outer end 32b is located substantially directly above the left and right ends of the heat transfer tube 25A, and has a length that is located substantially directly above the center of the lower heat transfer tube 25B, and is horizontally elongated downstream (upper side) of the upper heat transfer tube 25A. It is formed in a belt shape.

The cut-and-raised fins 33 in the middle stage are arranged outside the upper heat-transfer tubes 25A below the cut-and-raised fins 32 and on the upper half side of the upper heat transfer tube 25A (above the horizontal line L passing through the center). The inner end portion 33a is formed outside the inner end portion 32a of the cut-out fin 32, and the outer end portion 33b is formed in a horizontally long strip shape with a length located directly below the outer end portion 32b of the cut-out fin 32. .
The cut-and-raised fins 34 at the lowermost stage are arranged below the cut-and-raised fins 33 and on the lower half side of the upper heat transfer tube 25A so as to overlap the outer side of the upper heat transfer tube 25A in the left-right direction. The raised end fin 33 is located outside the inner end 33a, and the outer end 34b is also formed in a horizontally long strip shape with a length located inside the outer end 33b of the cut and raised fin 33.

Further, the inside of the can body 2a of the combustion device 2 includes a lower partition member 36 located between the first burner group 9 and the second burner group 10 in the lower casing 6, and a hot water supply side heat exchanger in the middle casing 7. A first combustion chamber 38 in which the first burner group 9 and the hot water supply side heat exchanger 13 are arranged by a partition member 35 including an upper partition member 37 located between the bath 13 and the bath-side heat exchanger 14; It is partitioned into a second combustion chamber 39 in which the second burner group 10 and the bath-side heat exchanger 14 are arranged.
Also, the left and right ends of each fin 15 of the hot water supply side heat exchanger 13 are cut up and down diagonally to form a rising piece 40 bent forward. Therefore, only the vertical intermediate portion 40 a of the rising piece 40 abuts on the upper partition member 37 and the middle casing 7. Similarly, the left and right ends of each of the fins 24 of the bath-side heat exchanger 14 are also cut obliquely at the top and bottom to form a rising piece 41 bent forward, and the upper partition member 37 and the middle casing 7 , Only the middle portion 41a in the up-down direction of the rising piece 41 comes into contact.

  Here, since the hot water supply side heat exchanger 13 having a small thickness in the vertical direction is disposed above the bath side heat exchanger 14, the middle portion of the rising piece 40 in the fin 15 of the hot water supply side heat exchanger 13 The position where 40a contacts the upper partition member 37 and the position where the intermediate portion 41a of the rising piece 41 of the fin 24 of the bath-side heat exchanger 14 contacts the upper partition member 37 are vertically displaced. Further, the upper end 15a and the lower end 15b of the fin 15 of the hot water supply side heat exchanger 13 are located above the upper end 24a and the lower end 24b of the fin 24 of the bath side heat exchanger 14, respectively. As a result, the vertical interval H1 between the first burner group 9 and the hot water supply side heat exchanger 13 in the first combustion chamber 38 is increased by the second burner group 10 and the bath side heat exchanger 14 in the second combustion chamber 39. Is larger than the vertical interval H2 between the two.

  An air supply chamber 42 is formed at a lower portion of the lower casing 6, and an air supply fan (not shown) is connected to a lower end thereof. A distribution plate 44 having a plurality of through holes 45 is attached to a partition plate 43 for partitioning between the first burner group 9 and the second burner group 10 and the air supply chamber 42. Air sent from the fan can be supplied to the first and second combustion chambers 38 and 39 through the through holes 45.

  In the water heater 1 configured as described above, when the hot water tap provided on the tapping pipe 20 is opened and water is passed through the combustion device 2, the water from the water supply pipe is supplied to the hot water supply side heat exchanger 13. It passes through the heat transfer tube 16. At the same time, a controller (not shown) ignites the first burner group 9 and rotates the air supply fan to supply combustion air from the air supply chamber 42 to the first burner group 9 via the distribution plate 44. The combustion gas of the first burner group 9 passes through the hot water supply side heat exchanger 13 in the first combustion chamber 38 and exchanges heat with the heat transfer pipe 16, and hot water at a predetermined temperature is discharged from the tapping pipe 22.

  On the other hand, when the additional cooking switch provided on the controller is turned ON, the controller drives the pump provided on the circulation path between the controller and the bathtub to ignite the second burner group 10 and rotate the air supply fan. The combustion air is supplied from the air supply chamber 42 to the second burner group 10 via the distribution plate 44. Hot water from the bathtub passes through the heat transfer tubes 25 of the bath-side heat exchanger 14, and the combustion gas of the second burner group 10 passes through the bath-side heat exchangers 14 in the second combustion chamber 39, so that the heat transfer tubes Heat exchange with 25. Therefore, the hot water in the bathtub is recirculated while being circulated.

Here, the combustion exhaust gas in the second combustion chamber 39 passes between the lower heat transfer tubes 25B and 25B and outside thereof as shown in FIG. 3, and stands as it is on the left and right outsides as shown by dotted arrow a. After being guided inward along the raising piece 41 and coming into contact with the outer end 33b of the cut-and-raised fin 33 and the outer end 32b of the cut-and-raised fin 32, respectively, it flows to the upper exhaust can 5.
On the other hand, the combustion exhaust gas that has passed between the lower heat transfer tubes 25B, 25B is separated and spreads from below the upper heat transfer tube 25A to the left and right, and a part of the combustion exhaust gas is supplied to the upper heat transfer tube 25A as indicated by a dashed line arrow b. After flowing in such a manner as to wrap around left and right, the inner end 34a of the cut-and-raised fin 34, the inner end 33a of the cut-and-raised fin 33, and the inner end 32a of the cut-and-raised fin 32 come in contact in this order, and then reach the upper exhaust can 5. . Further, as shown by the two-dot chain line arrow c, the other part of the combustion exhaust bulges further outward than the one-dot chain line arrow b, cuts and raises, contacts the outer end 34b of the fin 34, and flows along the dotted arrow a. The fins 33 merge and contact the outer end portion 33b of the cut-and-raised fin 32 and the outer end portion 32b of the cut-and-raised fin 32 in this order to reach the upper exhaust can 5. Thereby, each fin 24 can be brought into contact with the end of each of the cut-and-raised fins 32 to 34 along the flow of the combustion exhaust gas, and can effectively receive heat.

  As described above, according to the heat exchanger 4 (water heater 1) of the above-described embodiment, a plurality of cut-and-raised fins 32 to 34 arranged vertically at predetermined intervals on both left and right sides of the upper heat transfer tube 25A in each fin 24. Are formed, and the lowermost cut-and-raised fins 34 are arranged at positions where the lower end thereof overlaps the lower half of the upper heat transfer tube 25A in the left-right direction, so that three heat transfer tubes 25 are provided in the lower two rows and the upper one row. Also in the bath-side heat exchanger 14 arranged, high thermal efficiency can be obtained.

  Particularly, here, the cut-and-raised fins 32 to 34 are formed in three stages so that the length in the left-right direction increases from the lower stage to the upper stage, and the cut-and-raised fins 33 adjacent to the uppermost stage of the lowermost stage are formed in the lowermost stage. With respect to the cut-and-raised fin 34, the overhang of the outer end 33b is formed to be larger than the overhang of the inner end 33a. Since the overhanging fin 33 is formed such that the overhang of the inner end 32a is greater than the overhang of the outer end 32b, it passes between the upper heat transfer tube 25A and the lower heat transfer tube 25B. The cut-and-raised fins 32 to 34 can be arranged along the flow of the combustion exhaust, and further improvement in thermal efficiency can be expected.

Further, the interval between the upper heat transfer tube 25A and the lower heat transfer tube 25B is formed to be narrower than the diameter of the heat transfer tube 25, and further, below the upper heat transfer tube 25A in the fin 24, a belt-like shape covering the lower portion of the upper heat transfer tube 25A. Since the heat receiving portion 31 is provided and the lower heat transfer tube 25B is disposed at a position where the upper end overlaps the heat receiving portion 31 in the left-right direction, the interval between the upper heat transfer tube 25A and the lower heat transfer tube 25B is reduced. Therefore, it is possible to flow the combustion exhaust gas passing through the narrow gap so as to spread in the left-right direction, and to reliably contact the cut-and-raised fins 32 to 34.
Since the outer ends 32a, 33b of the cut-and-raised fins 32, 33 at the uppermost stage and the lower stage are located at the same position in the left-right direction, the combustion exhaust flowing outside the lower heat transfer tube 25B is separated from the outer ends 32b, 33b. Can be reliably contacted.
In addition, the inner ends 32a, 33a, and 34a of the cut-and-raised fins 32 to 34 in a plurality of stages are respectively extended to the upper heat transfer tube 25A side from the inner ends of the cut-and-raised fins adjacent to the lower stage. Since the positions are all different in the direction, it is possible to make effective contact with the combustion exhaust gas flowing around the outside of the upper heat transfer tube 25A.

In the above embodiment, the cut-and-raised fins 34 at the lowermost stage are arranged so as to entirely overlap the lower half of the upper heat transfer tube 25A in the left-right direction. If they overlap with each other, they may be arranged above the above embodiment.
Further, the positional relationship between the lower heat transfer tube 25B and the heat receiving portion 31 may be arranged higher than the above-described embodiment as long as at least the upper end of the lower heat transfer tube 25B overlaps the heat receiving portion 31 in the left-right direction.
Furthermore, the number of cut-and-raised fins is not limited to three, but may be two or four or more.

According to the combustion device 2 (water heater 1) of the above-described embodiment, the hot water supply side heat exchanger 13 and the bath side heat exchanger 14 are partially (started) at the ends of the fins 15 and 24 on the partition member 35 side. The intermediate section 40a of the section 40 and the intermediate section 41a) of the rising section 41 are accommodated in the combustion chambers 38 and 39, respectively, in contact with the partition member 35. By vertically shifting the position at which the intermediate portion 40a contacts the partition member 35 and the position at which the intermediate portion 41a of the end of the fin 24 in the bath-side heat exchanger 14 contacts the partition member 35, two Temporary assembly of the heat exchangers 13 and 14 and the partition member 35 can be facilitated and assembly can be performed smoothly.
Particularly, here, the fins 15 of the hot water supply side heat exchanger 13 are formed to have a smaller width in the vertical direction than the fins 24 of the bath side heat exchanger 14, and the upper ends of the fins 15 are located above the upper ends of the fins 24. Since it is located, the first combustion chamber 38 is formed to be wider in the vertical direction than the second combustion chamber 39, and a large combustion space of the first burner group 9 having a high combustion capacity can be secured. Therefore, it leads to stable combustion.

  In the above embodiment, the intermediate portion 40a at the fin 15 side of the hot water supply side heat exchanger 13 is connected to the partition member 35 above the intermediate portion 41a at the fin 24 side end of the bath side heat exchanger 14. Although the contact is made, the contact position may be upside down. Further, the contact portion is not limited to the intermediate portion, and may be a lower portion or an upper portion at the end of the fin. The rising piece may be a part instead of the entire end.

  In addition, the number of burners in the burner group in the combustion device, the form of the partition member, the structure of the can, and the like can be appropriately changed in design. The present invention can be applied to a device that is incorporated in a device or a device provided with a secondary heat exchanger for latent heat recovery.

  1. Hot water heater, 2. Combustion device, 3. Burner unit, 4. Heat exchanger, 5. Exhaust can, 6. Lower casing, 7. Middle casing, 8. Upper casing, 9 1st burner group, 10 2nd burner group, 11 burners, 13 hot water supply heat exchanger, 14 bath heat exchanger, 15 fins, 16 heat transfer tubes, 17 ..Connecting pipe, 22 .. tapping pipe, 24..fin, 25..heat transfer pipe (25A: upper heat transfer pipe, 25B: lower heat transfer pipe), 26..connection pipe, 28..return pipe, 30 .. Outgoing pipe, 31 heat receiving part, 32-34 cut-and-raised fin, 32a, 33a, 34a inner end, 32b, 33b, 34b outer end, 35 partition member, 38th 1 combustion chamber, 39 ··· second combustion chamber, 40, 41 ··· rising piece, 40a, 41a ··· intermediate part, 42 · The air supply chamber.

Claims (3)

A can body,
A first combustion chamber and a second combustion chamber partitioned by a partition member in the can body;
A first heat exchanger disposed in the first combustion chamber and having a plurality of fins and a plurality of heat transfer tubes penetrating the fins, and a first burner disposed below the first heat exchanger;
A second heat exchanger disposed in the second combustion chamber and having a plurality of fins and a plurality of heat transfer tubes penetrating the fins, and having a smaller flow rate than the first heat exchanger; And a second burner having a smaller amount of heat than the first burner,
The first heat exchanger and the second heat exchanger are housed in each of the combustion chambers in a state where a part of an end of the fin on the partition member side is in contact with the partition member,
A position where a part of an end of the fin in the first heat exchanger abuts on the partition member, and a position where a part of an end of the fin in the second heat exchanger abuts on the partition member. A combustion apparatus characterized in that the first heat exchanger and the second heat exchanger do not overlap with each other in a direction parallel to the first heat exchanger and the second heat exchanger .   The fins of the first heat exchanger are formed to have a smaller width in the vertical direction than the fins of the second heat exchanger, and the upper ends of the fins of the first heat exchanger are connected to the second heat exchanger. The combustion device according to claim 1, wherein the combustion device is located above an upper end of the fin of the exchanger.   A water heater comprising the combustion device according to claim 1.

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