JP7701699B2 - Water heater - Google Patents

Description

This disclosure relates to a water heater.

Patent Document 1 discloses an example of a water heater. In the water heater of Patent Document 1, a burner unit, a heat exchanger, an exhaust hood, etc. are housed in a housing, and an exhaust pipe is provided at the upper end of the exhaust hood. In this water heater, the exhaust hood is fixed directly to the heat exchanger, creating a fixed structure.

JP 2020-3148 A

In a water heater such as that described in Patent Document 1, when fixing an exhaust hood to a heat exchanger, a fixing structure with high sealing properties is required. For example, if a flange portion is provided at the upper end of the heat exchanger and a flange portion is provided at the lower end of the exhaust hood, and the flange portions are connected with a packing interposed between them, the sealing properties can be improved favorably near the boundary between the heat exchanger and the exhaust hood.

However, in this type of water heater, it may be desirable to provide a plate-like member separate from the outer shell (case) of the exhaust hood inside the exhaust hood. In such cases, it is desirable to fix the plate-like member inside the exhaust hood in a configuration that can achieve both "ensuring sealing" and "simple fixing."

One objective of this disclosure is to provide a technology for fixing a plate-shaped member inside the exhaust case in a water heater in a configuration that ensures both sealing and simple fixing.

The water heater according to the present disclosure is
A combustion device for burning gas;
A heat exchanger including a first case into which combustion exhaust gas generated by combustion in the combustion device is introduced and a heat transfer tube at least a portion of which is accommodated in the first case;
an exhaust section including a second case into which the combustion exhaust gas that has passed through the heat exchanger is introduced;
A packing sandwiched between the heat exchanger and the exhaust part;
having
the exhaust section includes a plate-like member accommodated in the second case,
the first case includes a peripheral wall portion that defines a flow path through which the combustion exhaust gas passes, and an upper flange portion that is provided at an upper end portion of the peripheral wall portion and protrudes outward,
The second case includes an outer wall portion that covers the heat exchanger from above, and a lower flange portion that is provided at a lower end portion of the outer wall portion and protrudes outward,
the plate-like member includes an inner disposed portion that is disposed inside the lower flange portion in the second case, and a fixing plate portion that continues from an outer edge portion of the inner disposed portion,
One of the upper flange portion and the lower flange portion has a bulging portion that bulges out toward an opposite side to the other flange portion,
The gasket is sandwiched between the upper flange portion and the lower flange portion on the outside of the bulge portion, and the fixing plate portion enters the bulge portion while being sandwiched between the inner surface of the bulge portion and the gasket, thereby fixing the upper flange portion and the gasket.

The technology disclosed herein allows a plate-shaped member to be fixed inside the exhaust case in a water heater in a configuration that ensures both sealing and simple fixing.

FIG. 1 is a front view illustrating a water heater according to a first embodiment. FIG. 2 is a front view illustrating the water heater of FIG. 1 with a front cover removed. FIG. 3 is a perspective view partially and roughly illustrating the vicinity of the exhaust section and the heat exchanger of the water heater of FIG. 1. FIG. FIG. 4 is an exploded perspective view partially and roughly illustrating the configuration of the exhaust unit and the heat exchanger of the water heater of FIG. 1 . FIG. 5 is a perspective cross-sectional view partially and diagrammatically showing the vicinity of the exhaust section and the heat exchanger of the water heater of FIG. FIG. 6 is an exploded perspective view of the configuration of FIG. FIG. 7 is a perspective cross-sectional view partially showing a connection structure between the exhaust portion and the heat exchanger.

Below, embodiments of the present disclosure are listed and exemplified. Note that the features [1] to [5] exemplified below may be combined in any compatible combination.

[1] a combustion device for burning gas;
A heat exchanger including a first case into which combustion exhaust gas generated by combustion in the combustion device is introduced and a heat transfer tube at least a portion of which is accommodated in the first case;
an exhaust section including a second case into which the combustion exhaust gas that has passed through the heat exchanger is introduced;
A packing sandwiched between the heat exchanger and the exhaust part;
having
the exhaust section includes a plate-like member accommodated in the second case,
the first case includes a peripheral wall portion that defines a flow path through which the combustion exhaust gas passes, and an upper flange portion that is provided at an upper end portion of the peripheral wall portion and protrudes outward,
The second case includes an outer wall portion that covers the heat exchanger from above, and a lower flange portion that is provided at a lower end portion of the outer wall portion and protrudes outward,
the plate-like member includes an inner disposed portion that is disposed inside the lower flange portion in the second case, and a fixing plate portion that continues from an outer edge portion of the inner disposed portion,
One of the upper flange portion and the lower flange portion has a bulging portion that bulges out toward an opposite side to the other flange portion,
The water heater has a configuration in which the gasket is sandwiched between the upper flange portion and the lower flange portion on the outside of the bulge portion, and the fixing plate portion fits into the bulge portion while being sandwiched between the inner surface of the bulge portion and the gasket, thereby fixing the upper flange portion and the gasket.

The water heater described in [1] can be fixed in a configuration in which the lower flange portion provided on the first case of the heat exchanger and the upper flange portion provided on the second case of the exhaust section are overlapped and a packing is sandwiched between the lower flange portion and the upper flange portion, so that both cases can be connected in a state of enhanced sealing. Furthermore, in this water heater, the plate-shaped member housed in the second case can be fixed by sandwiching the fixing plate portion of the plate-shaped member between the packing and one of the flange portions, so that the plate-shaped member can be fixed in a simpler configuration. However, if the fixing plate portion is simply sandwiched, the step between the one flange portion and the fixing plate portion will be large, and there is a concern that this will affect the sealing function of the packing. In this regard, the above-mentioned water heater is configured so that the fixing plate portion enters the bulging portion and is sandwiched between the inner surface of the bulging portion and the packing, so that the step between the surface of the fixing plate portion on the packing side and the surface of the one flange portion on the packing side outside the bulging portion is suppressed. Therefore, this water heater makes it easier to prevent the sealing ability of the packing from decreasing due to the structure that clamps the fixed plate.

[2] A contact portion that contacts the packing is provided in a region of the one flange portion that is not adjacent to the bulging portion,
The water heater described in [1], wherein the plate surface on the gasket side of the fixing plate portion is flush with the contact surface that contacts the gasket in the contact portion or is located on the opposite side of the gasket from the contact surface.

The water heater described in [2] has the packing side plate surface of the fixing plate portion positioned flush with the contact surface (surface that contacts the packing) of one of the flange portions or positioned on the opposite side of the packing from the contact surface, so that the packing side plate surface of the fixing plate portion can be prevented from protruding toward the packing. Therefore, this water heater can easily and effectively prevent a decrease in sealing performance caused by the fixing plate portion protruding toward the packing.

[3] A water heater as described in [1] or [2], wherein the first case and the second case are fixed to each other by plastic deformation of a crimp piece provided on at least one of the upper flange portion and the lower flange portion with the upper flange portion and the lower flange portion overlapping each other.

The water heater described in [3] is fixed by crimping (fixed by plastic deformation of the crimp piece) in a manner that minimizes the step between one of the flanges and the fixing plate, so that a large step can be prevented from adversely affecting the crimping fixation.

[4] Having an annular reinforcing member,
the reinforcing member is disposed so as to overlap the other flange portion while pressing a surface of the other flange portion opposite to the one flange portion,
The water heater according to [3], wherein the upper flange portion, the lower flange portion and the reinforcing member are fixed to each other by plastic deformation of the crimping piece provided on one of the flange portions.

The water heater described in [4] can easily and stably fix both flanges, packing, plate-like member, and reinforcing member by crimping, so that it can realize all of the following structures: a structure for fixing both flanges with high sealing performance, a structure for easily fixing the plate-like member, and a structure for reinforcing the area around both flanges with a reinforcing member.

[5] The exhaust section has an exhaust passage including an inlet arranged within the outer wall section and an exhaust port arranged on the outer side and above the outer wall section,
The exhaust path is configured with an exhaust flow path that flows the combustion exhaust gas from the inlet to the exhaust port so as to span the inside and the outside of the outer wall portion,
The plate-shaped member includes a plate-shaped partition wall that divides a space within the outer wall portion,
The partition wall is provided with a plurality of through holes and an opening portion having an opening area larger than each of the through holes,
The opening and the exhaust passage are continuous so that the combustion exhaust passing through the opening flows through the exhaust passage,
The water heater according to any one of [1] to [4], wherein an area above the partition wall in the space within the outer wall portion is blocked by the outer wall portion and the exhaust path.

In the water heater described in [5], a plate-shaped partition wall is provided to divide the space within the outer wall portion, and a plurality of through holes and an opening are provided in the partition wall, and the area above the partition wall in the space within the outer wall portion is blocked by the outer wall portion and the exhaust path. The opening and the exhaust path are connected so that the combustion exhaust gas passing through the opening flows through the exhaust flow path in the exhaust path. Since the water heater has such a configuration, it is difficult for a situation to occur in which gas passing near the plurality of through holes is discharged from the exhaust path as it passes through. In other words, in this water heater, when the combustion exhaust gas is discharged from the exhaust path, the presence of the plurality of through holes is unlikely to hinder the discharge in the exhaust path, and the combustion exhaust gas is likely to be discharged more smoothly. On the other hand, the configuration in which a partition wall provided with a plurality of through holes divides the space within the outer wall portion and the area above the partition wall is blocked by the outer wall portion and the exhaust path can adjust vibrations near the partition wall and adjust vibrations in the exhaust section. In particular, because the gas storage area is configured above the partition wall so that it is blocked by the outer wall and the exhaust path, and gas can pass through multiple through holes, a damping effect is easily generated and noise is easily suppressed.

First Embodiment
The following description relates to a water heater 1 according to the first embodiment.
1. Overall configuration of the water heater 1 Fig. 1 is a front view illustrating the water heater 1 according to the first embodiment. Fig. 2 is a front view illustrating a simplified configuration of the water heater 1 with the front cover 2A and the like removed from the housing 2.

As shown in FIG. 2, the water heater 1 includes a housing 2, a combustion device 3, a heat exchanger 4, an exhaust section 5, a fan 7, and the like. The housing 2 is a box-shaped case made of a metal material, and includes a housing body 2B that is a box-shaped body with an open front, and a front cover 2A (FIG. 1) that is attached and detached to the housing body 2B. The front cover 2A shown in FIG. 1 closes the housing body 2B from the front side. As shown in FIG. 2, the housing 2 houses each component such as the combustion device 3, the heat exchanger 4, the exhaust section 5, and the fan 7. The combustion device 3 is disposed near the center inside the housing 2. The heat exchanger 4 is disposed above the combustion device 3 inside the housing 2. The exhaust section 5 is disposed above the heat exchanger 4 inside the housing 2. The gas distribution unit 10 is disposed between the combustion device 3 and the front cover 2A. The fan 7 is disposed below the combustion device 3 inside the housing 2.

In the example shown in FIG. 1 etc., the up-down direction of the water heater 1 is the longitudinal direction of the water heater 1 when viewed from the front as in FIG. 1, for example, the vertical up-down direction when the water heater 1 is installed. In the example of FIG. 1, the up-down direction of the water heater 1 is the direction in which the cylindrical body 106 extends. In the example of FIG. 1, the longitudinal direction (direction of the long side) of the rectangular front part (front panel) of the front cover 2A is the up-down direction, the transverse direction (direction of the short side) of the front part (front panel) is the left-right direction, and the direction perpendicular to the up-down direction and left-right directions is the front-rear direction.

The combustion device 3 is a device that burns the combustion gas (specifically, the fuel gas supplied through the gas distribution unit 10) supplied from outside itself and generates combustion exhaust. The combustion exhaust is a high-temperature gas generated by the combustion of the combustion gas in the combustion device 3. The combustion device 3 includes an inner case 3A, a burner unit (not shown), and the like. The inner case 3A is a square box-shaped case that fits inside the housing 2. Inside the inner case 3A, a burner unit group is provided in which burner units, which are flattened light and dark burners, are arranged side by side in the left and right direction. Each light and dark burner (not shown) has a light side inlet and a rich side inlet (not shown) on the top and bottom, which open to the front and through which fuel gas and primary air are introduced, and at the top end, a flame port section consisting of a light flame hole in the center and rich flame holes on both the left and right sides of the light flame hole. An ignition discharge electrode, a flame rod for flame detection, and the like are provided on the upper front part of the inner case 3A.

The heat exchanger 4 includes a first case 20 made of metal that constitutes its outer shell, and a heat transfer tube 22 (FIG. 4) that is housed inside the first case 20. The heat exchanger 4 introduces the combustion exhaust from the combustion device 3 and passes it through its interior, and exchanges heat between the combustion exhaust and the water flowing in the heat transfer tube 22 to heat the water flowing in the heat transfer tube 22. The combustion exhaust that has passed through the heat exchanger 4 is discharged to the exhaust section 5. In the configuration of this embodiment, the first case 20 of the heat exchanger 4 is configured in a box shape with an open lower end and upper end. The first case 20 is a case into which the combustion exhaust (combustion exhaust generated by combustion in the combustion device 3) is introduced. The heat exchanger 4 shown in FIG. 4 and the like is configured such that a part of the heat transfer tube 22 is housed in the first case 20, and a predetermined area of the heat transfer tube 22 is disposed outside the first case 20.

The exhaust section 5 functions to guide the exhaust gas discharged from the heat exchanger 4 upward and discharge it to the outside of the water heater 1 through the cylindrical body 106. Details of the exhaust section 5 will be described later.

Fan 7 is a fan that supplies air for combustion. Fan 7 has a drive unit having a motor, blades, etc., and a supply port that supplies air for combustion, and sends the air for combustion from this supply port toward the combustion device 3. The supply port of fan 7 is fixed near the lower end of the combustion device 3.

The water heater 1 shown in Figs. 1 and 2 has a gas inlet 91 to which an external gas pipe is connected, a water inlet 92 to which a water pipe is connected, and a hot water outlet 93 provided on the underside of the housing 2. The water inlet 92 is an inlet through which water is introduced from a water pipe provided outside the water heater 1. The water introduced into the water inlet 92 is supplied to the heat transfer tube 22 (Fig. 4) of the heat exchanger 4 via a water supply pipe 115. A part of the water supply pipe 115 is illustrated in Fig. 2. The hot water outlet 93 is a hot water outlet that discharges hot water to the outside of the water heater 1. The hot water discharged from the heat transfer tube 22 of the heat exchanger 4 is discharged from the hot water outlet 93 via a hot water outlet pipe 116 connected to the downstream end of the heat transfer tube 22.

In the water heater 1 shown in FIG. 2, the gas inlet 91 is an inlet through which gas is introduced from a gas pipe provided outside the water heater 1. The gas introduced into the gas inlet 91 is supplied to the gas distribution unit 10 through a gas supply unit (not shown) equipped with a main valve, a proportional valve, etc. The gas supplied to the gas distribution unit 10 is distributed so as to pass through a plurality of holes (not shown) provided in the combustion device 3, and is supplied to the combustion device 3 through these holes. The combustion device 3 burns the gas (fuel gas) supplied into the combustion device 3 through the gas distribution unit 10. The exhaust gas (combustion exhaust gas) generated by the gas being burned in the combustion device 3 is discharged upward from the combustion device 3 and flows into the heat exchanger 4 from the opening at the lower end of the heat exchanger 4, and flows into the exhaust section 5 through the heat exchanger 4. The combustion exhaust gas flowing from the heat exchanger 4 to the exhaust section 5 side is introduced into the exhaust section 5 from the lower end of the exhaust section 5, and is discharged from the exhaust section 5 to the outside (outside the water heater 1).

2. Details of the Heat Exchanger The following description relates to details of the heat exchanger 4 in the water heater 1.
The heat exchanger 4 to which the exhaust section 5 is fixed has an open upper side so that an opening 20A is provided at the upper end, as shown in FIG. 4. The first case 20 of the heat exchanger 4 is, for example, a metal case made of a metal material. The first case 20 includes a front wall 23, a rear wall 24, and a pair of side walls 25, 26. The front wall 23, the rear wall 24, and the pair of side walls 25, 26 are connected in an annular configuration to form a peripheral wall 20Z. The peripheral wall 20Z forms a flow path through which the combustion exhaust passes. The front wall 23 and the rear wall 24 are both provided to extend left and right with the front-rear direction being the plate thickness direction, and are arranged to face each other in the front-rear direction. The pair of side walls 25, 26 are both provided to extend front and rear with the plate thickness direction being the left-right direction, and are arranged to face each other in the left-right direction. The upper ends of the front wall portion 23, the rear wall portion 24, and the pair of side wall portions 25, 26 form an opening portion 20A.

The upper end of the first case 20 is provided with an upper flange portion 20B that is configured in a flange shape and protrudes outward. The upper flange portion 20B is provided at the upper end of the peripheral wall portion 20Z so as to protrude outward. The upper flange portion 20B includes a forward protrusion portion 23A, a rear protrusion portion 24A, and side protrusion portions 25A and 26A. The forward protrusion portion 23A is provided so as to bend forward from the upper end of the front wall portion 23, and protrudes forward from the front wall portion 23. The rear protrusion portion 24A is provided so as to bend backward from the upper end of the rear wall portion 24, and protrudes forward from the front wall portion 23. The side protrusion portion 25A is provided so as to bend from the upper end of the side wall portion 25 to one side in the left-right direction (left side when viewed from the front), and protrudes from the side wall portion 25 to one side in the left-right direction (left side when viewed from the front). The lateral projection 26A is bent from the upper end of the side wall 26 to the other side in the left-right direction (right side when viewed from the front), and protrudes from the side wall 26 to the other side in the left-right direction (right side when viewed from the front).

3. Details of the Exhaust Section The following description relates to details of the exhaust section 5 in the water heater 1.
The exhaust unit 5 shown in Figures 2 and 3 is a device that forms a path for introducing the combustion exhaust gas that has passed through the heat exchanger 4 into the inside and discharging it to the outdoors. The exhaust unit 5 is fixed to the upper end of the heat exchanger 4 and disposed above the heat exchanger 4. As shown in Figures 4 and 6, the exhaust unit 5 mainly includes a second case 30, a plate-shaped member 50, a packing 70, and a reinforcing member 80. The reinforcing member 80 may be configured as a part of the heat exchanger 4, or may be configured independently of the heat exchanger 4 and the exhaust unit 5.

The second case 30 shown in FIG. 3 is, for example, a metal case made of a metal material. The second case 30 is fixed to the upper end of the heat exchanger 4 and is arranged above the heat exchanger 4 so as to cover the heat exchanger 4. The second case 30 is a case into which the combustion exhaust gas that has passed through the heat exchanger 4 is introduced. The second case 30 has an outer wall portion 32 and a lower flange portion 34. The outer wall portion 32 has a peripheral wall portion 35 that surrounds both the front and rear sides and both the left and right sides of the space into which the combustion exhaust gas is released from the heat exchanger 4, and an upper wall portion 37 that is continuous with the upper side of the peripheral wall portion 35. As shown in FIG. 3, the peripheral wall portion 35 has a front wall portion 35A, a rear wall portion 35B, and side wall portions 35C and 35D, which are integrally connected to surround the front, rear, left and right sides of the space within the second case 30. The front wall 35A, the rear wall 35B, and the side walls 35C and 35D are all provided to rise upward from the annular lower flange 34, and the upper wall 37 is connected to the upper end of each. The lower flange 34 is annularly protruding outward (specifically, both front and rear and both left and right) from the lower end of the peripheral wall 35, and has a flange-like shape. As shown in FIG. 5, the lower flange 34 is disposed on the upper flange 20B of the heat exchanger 4, and is fixed to the upper flange 20B with a packing 70 sandwiched therebetween (see also FIG. 7). In the example of FIG. 3, the lower flange 34 and the upper flange 20B are fixed to each other by a crimping process that bends the crimp piece 34Z provided on the lower flange 34. Note that FIG. 4 shows a state in which the crimp piece 34Z is not bent, and FIG. 3 shows a fixed state after the crimp piece 34Z is bent.

As shown in FIG. 3, the upper wall portion 37 of the second case 30 has a first upper wall portion 37Z that covers the upper side of the first partition wall 51, and second upper wall portions 37A and 37B that are arranged on both the left and right sides of the first upper wall portion 37Z. The first upper wall portion 37Z and the second upper wall portions 37A and 37B are both configured in a plate shape. The first upper wall portion 37Z is arranged so that the plate thickness direction is the up-down direction. As shown in FIG. 4 and FIG. 6, the first upper wall portion 37Z has an opening 39 that penetrates the first upper wall portion 37Z. The exhaust path 100 is inserted into the opening 39. Specifically, a cylindrical portion 38 is provided so as to rise upward from the first upper wall portion 37Z, and the inner periphery of the cylindrical portion 38 is the opening 39. As shown in FIG. 3, the exhaust path 100 and the cylindrical portion 38 are in close contact with each other so that the cylindrical portion 38 and the cylinder body 106 fit together.

As shown in FIG. 5, the second upper wall portion 37A is arranged so as to cover the upper side of the second partition wall 52A. The second upper wall portion 37A is arranged at an incline along the second partition wall 52A, and the lower surface of the second upper wall portion 37A is inclined so as to be lower as it moves away from the first upper wall portion 37Z in the left-right direction. The second upper wall portion 37B is arranged so as to cover the upper side of the second partition wall 52B. The second upper wall portion 37B is arranged at an incline along the second partition wall 52B, and the lower surface of the second upper wall portion 37B is inclined so as to be lower as it moves away from the first upper wall portion 37Z in the left-right direction.

The second case 30 thus constructed is entirely disposed above the heat exchanger 4, and a space is formed within itself through which the exhaust gas from combustion passes. In the second case 30, an opening provided at the lower end of the outer wall portion 32 is the inlet 42, which serves as an inlet through which the exhaust gas from combustion passes through the heat exchanger 4. The inlet 42 is connected to the opening 20A of the heat exchanger 4, and gas discharged upward from the heat exchanger 4 through the opening 20A flows into the second case 30 (specifically, into the outer wall portion 32) through the inlet 42.

The exhaust passage 100 shown in Figs. 3 and 4 is a component for discharging the combustion exhaust gas introduced into the second case 30 (specifically, the combustion exhaust gas that has entered the second case 30 from the first case 20 of the heat exchanger 4) to the outside of the second case 30, and is a path for discharging the combustion exhaust gas to the outside of the water heater 1. As shown in Fig. 5, the exhaust passage 100 includes an inlet 102 disposed within the outer wall portion 32, and an outlet 104 disposed on the outer side and above the outer wall portion 32. The exhaust passage 100 is configured with an exhaust flow path 100A that flows the combustion exhaust gas from the inlet 102 to the outlet 104 so as to span the inside and outside of the outer wall portion 32.

As shown in FIG. 4, the exhaust passage 100 includes a cylindrical body 106. An exhaust flow path 100A is formed inside the cylindrical body 106, through which the combustion exhaust gas flows. The inner wall of the cylindrical body 106 functions as the exhaust flow path 100A. In the example of FIG. 3 and FIG. 4, the cylindrical body 106 is cylindrical. The cylindrical body 106 has a plurality of cylindrical portions 106A, 106B, and 106C formed as a cylinder centered on a predetermined central axis. The central axis is, for example, an axis in the vertical direction. The inner and outer circumferential surfaces of the cylindrical portions 106A, 106B, and 106C are cylindrical surfaces centered on the central axis. The plurality of cylindrical portions 106A, 106B, and 106C are integrally formed in a form connected vertically.

5, the inlet 102 is an opening provided at the lower end of the cylindrical body 106. The inlet 102 is an inlet for introducing gas present in the space outside the cylindrical body 106 in the outer wall portion 32 into the cylindrical body 106. The outlet 104 is an opening provided at the upper end of the cylindrical body 106. The outlet 104 is an outlet for discharging the gas in the cylindrical body 106 to the outside of the water heater 1. The cylindrical body 106 is configured such that at least a portion of the upper end side is exposed to the outside of the housing 2 (FIG. 1). Specifically, the outlet 104 and the vicinity of the outlet 104 are exposed to the space outside the water heater 1. Because of this configuration, the combustion exhaust gas flowing upward through the cylindrical body 106 is discharged to the outside of the water heater 1 from the outlet 104.

The backwind suppression mechanism 90 shown in FIG. 5 is a mechanism that suppresses the reverse flow of gas in the cylindrical body 106 toward the housing 2 (specifically, the flow of gas from the exhaust port 104 side toward the inlet port 102 side). The backwind suppression mechanism 90 is provided inside the cylindrical body 106. The backwind suppression mechanism 90 mainly comprises an attachment member 110 and a flap 120. The attachment member 110 is a member that is attached inside the cylindrical body 106. The attachment member 110 supports the flap 120 so that it can rotate freely. The flap 120 is configured as a plate overall, and is displaced between a closed position that closes a predetermined position inside the cylindrical body 106, and an open position that opens the predetermined position to a greater degree than when in the closed position. When gas flows from the exhaust port 104 side to the inlet port 102 side, the flap 120 is displaced to the closed position, and when gas flows from the inlet port 102 side to the exhaust port 104 side, the flap 120 is displaced to the open position (see FIG. 5).

As shown in FIG. 5, the plate-shaped member 50 is a part that divides the space in the outer wall portion 32. The plate-shaped member 50 is housed in the second case 30. As shown in FIG. 4, the plate-shaped member 50 includes an inner arrangement portion 50Z that is arranged inside the lower flange portion 34 in the second case 30, and a fixed plate portion 50X that continues from the outer edge of the inner arrangement portion 50Z. The inner arrangement portion 50Z includes a partition wall 50A and connecting portions 50B and 50C. The partition wall 50A is a plate-shaped wall that divides the space in the outer wall portion 32. The partition wall 50A is provided with a plurality of through holes 58 and an opening portion 54 that has an opening area larger than each of the through holes 58 (see also FIG. 4 and FIG. 6). In the configuration of FIG. 5, the area above the partition wall 50A in the space in the outer wall portion 32 is blocked by the outer wall portion 32 and the exhaust path 100.

As shown in FIG. 5, the partition wall 50A has a plate-shaped portion 60 with one plate surface 60A (upper surface) facing upward and the other plate surface (lower surface) facing downward. The plate-shaped portion 60 includes a plate-shaped portion constituting the first partition wall 51 and a plate-shaped portion constituting each of the second partition walls 52A and 52B. Each through hole 58 penetrates the plate-shaped portion 60 between one plate surface 60A and the other plate surface (lower surface).

The inner arrangement portion 50Z has a tubular portion 56 that continues to the partition wall 50A so as to continue upward or downward from the partition wall 50A. The tubular portion 56 is configured as a cylinder. The central axis of the cylinder of the tubular portion 56 coincides with the central axis of the cylinder of the tubular body 106. The inner wall portion of the tubular portion 56 is configured as an opening 54. The tubular portion 56 is configured to rise upward from the partition wall 50A and continues to the partition wall 50A. As shown in FIG. 5, the tubular portion 56 and the tubular body 106 are fitted together so as to fit into the tubular portion 56 from the outside, and the exhaust path 100 is fixed to the plate-like member 50. The lower end of the tubular body 106 is located above the lower end of the opening 54. With this configuration, the opening 54 and the exhaust path 100 are continuous so that the combustion exhaust passing through the opening 54 flows through the flow path in the exhaust path 100.

4 and 5, the partition wall 50A includes a first partition wall 51 and a pair of second partition walls 52A and 52B arranged on both sides of the first partition wall 51 in the left-right direction. Each of the second partition walls 52A and 52B has one end connected to the first partition wall 51 in the left-right direction. The lower surface of each of the second partition walls 52A and 52B is arranged so that it is positioned lower as it moves away from the first partition wall 51 in the left-right direction. The second partition wall 52A arranged on one side in the left-right direction is inclined with one side in the left-right direction lowering (specifically, a left-downward configuration) so that it is positioned lower as it moves toward one side in the left-right direction (as it moves away from the first partition wall 51). The second partition wall 52B arranged on the other side in the left-right direction is inclined with the other side in the left-right direction lowering (specifically, a right-downward configuration) so that it is positioned lower as it moves toward the other side in the left-right direction (as it moves away from the first partition wall 51).

In such a partition wall 50A, at least the second partition walls 52A and 52B are provided with through holes 58. In the example of FIG. 4 to FIG. 6, the first partition wall 51 and the second partition walls 52A and 52B are both provided with through holes 58. Specifically, multiple rows (specifically, three rows) of through holes 58 aligned in the left-right direction are provided in a configuration that straddles the second partition wall 52A and the first partition wall 51. In each row of through holes 58, the through holes 58 are aligned at equal intervals. Similarly, multiple rows (specifically, three rows) of through holes 58 aligned in the left-right direction are provided in a configuration that straddles the second partition wall 52B and the first partition wall 51. In each row of through holes 58, the through holes 58 are aligned at equal intervals.

The connecting portions 50B and 50C shown in FIG. 6 are portions that are connected to the partition wall 50A and that extend vertically downward from the ends of the second partition walls 52A and 52B. The connecting portion 50B connects the partition wall 50A to the fixing plate portion 50X and extends downward from the end of one side of the partition wall 50A in the left-right direction. The connecting portion 50C connects the partition wall 50A to the fixing plate portion 50Y and extends downward from the end of the other side of the partition wall 50A in the left-right direction. The connecting portions 50B and 50C form both ends of the inner portion 50Z.

The fixing plate portions 50X and 50Y are portions that act to fix the plate-like member 50 to the heat exchanger 4 and the exhaust section 5, and are specifically portions that are sandwiched and fixed between the upper flange portion 20B and the lower flange portion 34. Both of the fixing plate portions 50X and 50Y are plate-like portions that extend from the outer edge of the inner-positioning portion 50Z. The fixing plate portion 50X is a plate-like portion that extends from the outer edge of one of the left and right sides of the inner-positioning portion 50Z to one left and right side (the opposite side to the inner-positioning portion 50Z), and specifically extends from the lower end of the connecting portion 50B to one left and right side (the opposite side to the inner-positioning portion 50Z). The fixed plate portion 50Y is a plate-shaped portion that extends from the outer edge of the other left-right side of the inner portion 50Z to the other left-right side (the opposite side to the inner portion 50Z), and specifically extends from the lower end of the connecting portion 50C to one left-right side (the opposite side to the inner portion 50Z). The fixed plate portions 50X, 50Y are arranged, for example, such that the plate thickness direction is the up-down direction. In both fixed plate portions 50X, 50Y, one plate surface (upper surface) faces upward and the other plate surface (lower surface) faces downward.

4. Details of Fixing Structure The packing 70 is a sealing member sandwiched between the heat exchanger 4 and the exhaust section 5. As shown in Fig. 4, the packing 70 is configured in an annular shape. Specifically, the packing 70 has a rectangular frame shape that conforms to the shape of the upper flange portion 20B, and a rectangular frame shape that conforms to the shape of the lower flange portion 34. The packing 70 may be made of any known material that has sealing properties, and known sealing materials such as rubber, elastomer, and other resin materials may be used.

As shown in FIG. 4, the second case 30 of the exhaust section 5 includes an outer wall portion 32 that covers the heat exchanger 4 from above, and a lower flange portion 34 that protrudes outward from the lower end of the outer wall portion 32. As shown in FIG. 7, the lower flange portion 34 has a bulge portion 40 and a contact portion 48.

The bulging portion 40 is a portion formed to bulge on the opposite side to the upper flange portion 20B of the heat exchanger 4. The inner surface 40A, which is the lower surface of the bulging portion 40, is concave and recessed upward. The inner wall upper surface 40B, which is the upper end surface of the inner surface 40A, is a flat surface (e.g., a flat surface in a direction perpendicular to or intersecting the up-down direction). In the bulging portion 40, the space surrounded by the inner surface 40A is the space that houses the fixing plate portion 50X.

The contact portion 48 is a portion of the lower flange portion 34 that is provided in an area outside the bulge portion 40, and is a portion that contacts the packing 70. The bulge portion 40 and the contact portion 48 are both configured in a plate shape, and are configured in a stepped shape so that the bulge portion 40 is located above the contact portion 48. The lower surface of the contact portion 48 includes a contact surface 48A that extends around the entire circumference of the lower flange portion 34. The contact surface 48A is a surface that contacts the upper surface of the packing 70, and is, for example, a flat surface. The contact surface 48A and the inner wall upper surface 40B are parallel or approximately parallel. The inner wall upper surface 40B is located above the contact surface 48A.

In the fixing structure of FIG. 7, a packing 70 is sandwiched between the upper flange portion 20B and the lower flange portion 34 on the outside of the bulging portion 40. Specifically, the packing 70 is sandwiched between the upper surface of the upper flange portion 20B, which is configured in a plate shape, and the above-mentioned contact surface 48A, and the upper surface of the upper flange portion 20B and the contact surface 48A are in close contact with the packing 70. Furthermore, the upper flange portion 20B and the packing 70 are fixed in a configuration in which the fixing plate portion 50X is inserted into the bulging portion 40 and sandwiched between the inner surface 40A (specifically, the inner wall upper surface 40B) of the bulging portion 40 and the packing 70. The fixing plate portion 50X is fixed in a configuration in which it is sandwiched between the inner wall upper surface 40B and the upper surface of the packing 70.

The plate surface 68 (surface that contacts the packing 70) on the side of the packing 70 in the fixed plate portion 50X is flush with the contact surface 48A that contacts the packing 70 in the contact portion 48, or is located on the opposite side (upper side) of the packing 70 than the contact surface 48A. In the example of FIG. 7, the plate surface 68 is located above the contact surface 48A, and part of the packing 70 is inserted into the bulge portion 40, but the plate surface 68 and the contact surface 48A may be flush and aligned so as to be at the same position in the vertical direction.

The reinforcing member 80 shown in FIG. 7 is a member that reinforces the fixing structure of the upper flange portion 20B and the lower flange portion 34. As shown in FIG. 4, the reinforcing member 80 is configured in an annular shape. The reinforcing member 80 is in close contact with the entire circumference of the upper flange portion 20B so as to support the upper flange portion 20B over the entire circumference of the upper flange portion 20B. As shown in FIG. 7, the reinforcing member 80 is arranged overlapping the upper flange portion 20B while pressing the surface 28 (lower surface) of the upper flange portion 20B (the other flange portion) opposite the lower flange portion 34 (one flange portion). The reinforcing member 80 includes an annular plate portion 82, an inner falling portion 84, and an outer falling portion 86. The annular plate portion 82 is configured in an annular and plate-like shape and is arranged to be in close contact with the upper flange portion 20B over the entire circumference of the upper flange portion 20B. The inner falling portion 84 is provided so as to fall downward from the inner edge of the annular plate portion 82 and is provided along the peripheral wall portion 20Z. The outer falling portion 86 is provided so as to fall downward from the outer edge of the annular plate portion 82 and is provided adjacent to the outer falling portion 46 of the second case 30 so as to follow the outer falling portion 46.

As shown in Figs. 3 and 4, the lower flange portion 34 has a contact portion 48 that is annular (specifically, rectangular frame-shaped) and plate-shaped around the outer wall portion 32, and an outer falling portion 46 that is annularly provided to fall from the outer edge of the annular contact portion 48. The outer falling portion 46 is configured as an annular peripheral wall portion that surrounds the packing 70, the upper flange portion 20B, and the reinforcing member 80 on the front, rear, left and right sides. Crimping pieces 34Z are provided at multiple locations on the lower end of the outer falling portion 46. The shape of each crimping piece 34Z before fixing is as shown in Fig. 4, and the shape after fixing is as shown in Fig. 3 (a shape plastically deformed from the shape shown in Fig. 4).

In the configuration of FIG. 7, the first case 20 and the second case 30 are fixed to each other by plastic deformation of the crimping piece 34Z (see FIG. 3 and FIG. 4) provided on the lower flange portion 34 with the upper flange portion 20B and the lower flange portion 34 overlapping. Specifically, the upper flange portion 20B, the lower flange portion 34, the packing 70, and the reinforcing member 80 are fixed to each other by plastic deformation of the crimping piece 34Z provided on one of the flange portions. In the example of FIG. 3 and FIG. 7, when the reinforcing member 80 is fitted to the outside of the upper end portion of the peripheral wall portion 20Z and the upper flange portion 20B and the packing 70 are sandwiched between the annular plate portion 82 of the reinforcing member 80 and the contact portion 48, the shape of the crimping piece 34Z (specifically, a shape bent inward from the outer falling portion 46) is set so as to restrict the downward movement of the outer falling portion 86, and the reinforcing member 80 is prevented from falling out downward. Because this sandwiching structure is maintained, the fixing plate portion 50X is held in a fixed state sandwiched between the inner wall upper surface 40B of the bulging portion 40 and the packing 70.

5. Example of Effects The water heater 1 can be fixed in a configuration in which the lower flange portion 34 provided on the first case 20 of the heat exchanger 4 and the upper flange portion 20B provided on the second case 30 of the exhaust section 5 are overlapped and the packing 70 is sandwiched between the lower flange portion 34 and the upper flange portion 20B, so that both cases can be connected in a state of improved sealing. Furthermore, in this water heater 1, the plate-shaped member 50 housed in the second case 30 can be fixed by sandwiching the fixing plate portion 50X of the plate-shaped member 50 between the packing 70 and one of the flange portions, so that the plate-shaped member 50 can be fixed in a simpler configuration. However, if the fixing plate portion 50X is simply sandwiched, the step between the one flange portion and the fixing plate portion 50X becomes large, and there is a concern that this may affect the sealing function of the packing 70. In this regard, since the water heater 1 is configured such that the fixing plate 50X fits inside the bulging portion 40 and is sandwiched between the inner surface of the bulging portion 40 and the packing 70, the step between the face of the fixing plate 50X facing the packing 70 and the face of one of the flanges facing the packing 70 outside the bulging portion 40 is reduced. Therefore, this water heater 1 makes it easy to prevent a decrease in the sealing performance of the packing 70 caused by the structure that sandwiches the fixing plate 50X.

In the water heater 1, the plate surface 68 on the packing 70 side of the fixing plate portion 50X is positioned flush with the contact surface 48A (surface that contacts the packing 70) of one flange portion (lower flange portion 34) or positioned on the opposite side of the packing 70 from the contact surface, so that the plate surface 68 can be prevented from protruding toward the packing 70. Therefore, this water heater 1 makes it easy to effectively prevent a decrease in sealing performance caused by the fixing plate portion 50X protruding toward the packing 70.

The water heater 1 is fixed by crimping (by plastic deformation of the crimp piece 34Z) in a manner that minimizes the step between one of the flange portions (lower flange portion 34) and the fixing plate portion 50X, preventing a large step from adversely affecting the crimping fixation.

The water heater 1 can easily and stably fix both flanges, the packing 70, the plate-like member 50, and the reinforcing member 80 with crimping, so that it can realize all of the following structures: a structure for fixing both flanges with high sealing performance, a structure for easily fixing the plate-like member 50, and a structure for reinforcing the area around both flanges with the reinforcing member 80.

In the water heater 1, a plate-shaped partition wall 50A is provided to divide the space in the outer wall portion 32, and a plurality of through holes 58 and an opening 54 are provided in the partition wall 50A, and the area above the partition wall 50A in the space in the outer wall portion 32 is blocked by the outer wall portion 32 and the exhaust path 100. The opening 54 and the exhaust path 100 are connected so that the combustion exhaust passing through the opening 54 flows through the exhaust flow path 100A in the exhaust path 100. Since the water heater 1 is configured in this way, it is difficult for a situation to occur in which gas passing near the plurality of through holes 58 is discharged from the exhaust path 100 as it is. In other words, in this water heater 1, when the combustion exhaust is discharged from the exhaust path 100, the presence of the plurality of through holes 58 is less likely to hinder discharge in the exhaust path 100, and the combustion exhaust is more likely to be discharged smoothly. On the other hand, "the partition wall 50A with multiple through holes 58 divides the space inside the outer wall portion 32, and the area above the partition wall 50A is blocked by the outer wall portion 32 and the exhaust path 100," so that it is possible to adjust the vibration near the partition wall 50A and adjust the vibration of the exhaust portion 5. In particular, because the gas storage portion is configured above the partition wall 50A so as to be blocked by the outer wall portion 32 and the exhaust path 100, and the gas can pass through the multiple through holes 58, a damping effect is easily generated and noise is easily suppressed.

<Other embodiments>
The present invention is not limited to the embodiments described above and in the drawings. For example, the features of the above or later described embodiments can be combined in any combination within a range that does not contradict. Furthermore, any feature of the above or later described embodiments can be omitted unless it is clearly stated as essential. Furthermore, the above described embodiments may be modified as follows.

In the above embodiment, the bulge portion is provided on the lower flange portion 34, but the bulge portion may be provided on the upper flange portion 20B. In this case, the bulge portion only needs to be configured to bulge downward. In this configuration, the bulge portion only needs to be configured to bulge to a size that can accommodate the fixing plate portion 50X in its internal space. In this case, the lower flange portion 34 and the packing 70 are fixed in a configuration in which the fixing plate portion 50X fits into the bulge portion and is sandwiched between the inner surface of the bulge portion and the packing 70.

In the above-described embodiment, as shown in FIG. 4 etc., a portion of the heat transfer tube 22 is housed within the first case 20, and a predetermined area of the heat transfer tube 22 is disposed outside the first case 20. However, it is sufficient that at least a portion of the heat transfer tube is disposed within the first case; for example, the entire heat transfer tube of the heat exchanger may be housed within the first case.

In the embodiment described above, the entire outer wall portion 32 is positioned above the heat exchanger 4, but only a portion of the outer wall portion may be positioned above the heat exchanger 4, with the other portion being positioned offset from above the heat exchanger 4.

In the embodiment described above, the tube 106 is configured to have a cylindrical shape, but the tube may have any shape as long as it is cylindrical, and may be, for example, a rectangular tube.

It should be noted that the embodiments disclosed herein are illustrative in all respects and should not be considered restrictive. The scope of the present invention is not limited to the embodiments disclosed herein, but is intended to include all modifications within the scope of the claims or within the scope equivalent to the claims.

1: Water heater 2: Housing 3: Combustion device 4: Heat exchanger 5: Exhaust section 20: First case 20B: Upper flange section (other flange section)
20Z: peripheral wall portion 22: heat transfer tube 30: second case 32: outer wall portion 34: lower flange portion (one flange portion)
34Z: Crimping piece 40: Bulging portion 48: Contact portion 48A: Contact surface 50: Plate-shaped member 50A: Partition wall 50X: Fixing plate portion 50Z: Inner portion 54: Opening 58: Through hole 70: Packing 80: Reinforcing member 100: Exhaust passage 100A: Exhaust passage 102: Inlet 104: Exhaust port

Claims (5)

A combustion device for burning gas;
A heat exchanger including a first case into which combustion exhaust gas generated by combustion in the combustion device is introduced and a heat transfer tube at least a portion of which is accommodated in the first case;
an exhaust section including a second case into which the combustion exhaust gas that has passed through the heat exchanger is introduced;
A packing sandwiched between the heat exchanger and the exhaust part;
having
the exhaust section includes a plate-like member accommodated in the second case,
the first case includes a peripheral wall portion that defines a flow path through which the combustion exhaust gas passes, and an upper flange portion that is provided at an upper end portion of the peripheral wall portion and protrudes outward,
The second case includes an outer wall portion that covers the heat exchanger from above, and a lower flange portion that is provided at a lower end portion of the outer wall portion and protrudes outward,
the plate-like member includes an inner disposed portion that is disposed inside the lower flange portion in the second case, and a fixing plate portion that continues from an outer edge portion of the inner disposed portion,
One of the upper flange portion and the lower flange portion has a bulging portion that bulges out toward an opposite side to the other flange portion,
The water heater has a configuration in which the gasket is sandwiched between the upper flange portion and the lower flange portion on the outside of the bulge portion, and the fixing plate portion fits into the bulge portion while being sandwiched between the inner surface of the bulge portion and the gasket, thereby fixing the upper flange portion and the gasket. a contact portion that contacts the packing is provided in a region of the one flange portion that is not adjacent to the bulging portion,
The water heater according to claim 1 , wherein the plate surface of the fixing plate portion facing the gasket is flush with a contact surface of the contact portion that contacts the gasket or is located on the opposite side of the gasket from the contact surface. The water heater of claim 1 or claim 2, wherein the first case and the second case are fixed to each other by plastic deformation of a crimping piece provided on at least one of the upper flange portion and the lower flange portion with the upper flange portion and the lower flange portion overlapping each other. A ring-shaped reinforcing member is provided.
the reinforcing member is disposed so as to overlap the other flange portion while pressing a surface of the other flange portion opposite to the one flange portion,
The water heater according to claim 3 , wherein the upper flange portion, the lower flange portion and the reinforcing member are fixed to each other by plastic deformation of the crimping piece provided on one of the flange portions. The exhaust section has an exhaust path including an inlet disposed within the outer wall section and an exhaust port disposed on the outer side and above the outer wall section,
The exhaust path is configured with an exhaust flow path that flows the combustion exhaust gas from the inlet to the exhaust port so as to span the inside and the outside of the outer wall portion,
The plate-shaped member includes a plate-shaped partition wall that divides a space within the outer wall portion,
The partition wall is provided with a plurality of through holes and an opening portion having an opening area larger than each of the through holes,
The opening and the exhaust passage are continuous so that the combustion exhaust passing through the opening flows through the exhaust passage,
The water heater according to claim 1 , wherein an area above the partition wall in the space within the outer wall portion is blocked by the outer wall portion and the exhaust path.

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