JP2003021319A - Burner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a burner which is capable of performing silent operation by reducing the noise caused by the exhaust cylinder in itself. SOLUTION: The burner 1, which has a blower 8 and a combustor 3 for generating a flame by injecting fuel and supplies the combustor 3 with air from blower 8 thereby burning the fuel, is equipped with an exhaust cylinder 5 for discharging the exhaust gas, and a part or the whole of the exhaust cylinder 5 is provided with irregularity 46p. Preferably, the shape of the irregularity is either one of the shapes of a column, a hemisphere, a trigonal prism, a cone, a trigonal pyramid, or a burring.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion device, for example, a device suitable as a combustion device incorporated in a water heater, a bath device or the like.

[0002]

2. Description of the Related Art Water heaters are widely used in ordinary households.
In recent years, hot water heaters mainly have a structure with a built-in blower. FIG. 23 is a cross-sectional view showing an internal configuration of a combustion device incorporated in a conventional water heater.

In a conventional combustion apparatus 100, a plurality of burner members 102 are built in a box body called a burner case 101, and a blower 1 is provided below the burner case 101.
03 is attached. That is, the burner case 101 is a rectangular box, and is a member in which the bottom plate portion and the side surface portions are covered with plates and the top surface side is open. An opening 104 is provided in the bottom plate portion of the burner case 101, and the blower port of the blower 103 is directly connected to the opening 104. Further, the opening on the upper surface side of the burner case 101 communicates with the heat exchange section 107, and the heat exchange section 107.
Is connected to the exhaust pipe 108 on the further downstream side.

Next, the flow paths of air and fuel in the conventional combustion device 100 will be described. In the conventional combustion device 100, air is supplied by the blower 103 provided in the lower part. Further, the fuel nozzle 106 is inserted into the fuel inlet 102a of the burner member 102, and the fuel is supplied from the fuel nozzle 106 into the burner member 102.

Regarding the flow of air, there are primary air that is premixed with the fuel and secondary air that is supplied to the fuel after the fuel is injected from the flame holes. Therefore, the air flow will be described separately for the primary air and the secondary air. That is, as described above, in the conventional combustion device 100, the air is supplied into the burner case 101 by the blower 103 provided below the burner case 101. A part of the supplied air flows along the lower surface of the partition plate 105 and enters the void portion 105a formed by the step portion of the partition plate 105. Then, it is entrained in the fuel gas flow injected from the fuel nozzle 106, and is discharged from the flame hole 102b of the burner member 102.

On the other hand, the secondary air enters the interior surrounded by the burner case 101 directly from a large number of ventilation holes (not shown) provided in the partition plate 105. And the burner member 10
It passes through the gap between the two and escapes to the flame hole 102b side. Then, the air is mixed with fuel inside the burner member 102,
A lean mixed gas is generated and discharged from the flame hole 102b.

The combustion gas that has generated a flame in the flame hole 102b rises upward in the burner case 101 and enters the heat exchange section 107. In the heat exchange section 107, the heat of the rising combustion gas is heat-exchanged with the hot water supply pipe 107b via the fins 107a, and the heat-exchanged combustion gas reaches the exhaust pipe 108 as exhaust gas.

The exhaust cylinder 108 is in the shape of a box whose lower and left sides are open, and is attached so as to cover the heat exchange section 107 from above. Then, the exhaust cylinder 108 discharges the exhaust gas rising from the heat exchange section 107 from the exhaust port 108a by deflecting the flow direction laterally. A draining member 109 for discharging rainwater entering through the exhaust port 108a is provided inside the exhaust pipe 108, and an exhaust top 110 is provided outside the exhaust port 108a.
Is attached.

[0009]

By the way, it is important that household water heaters and the like are often installed in a place facing a passageway in a condominium or in a space between houses, and have little noise. . Here, as one of the causes of noise generation, there is passing noise generated when the air flow (combustion gas flow) generated by the blower 103 passes through the air flow path. In other words, the combustion device 100 of the related art produces a loud noise due to the flow of air and is offensive to the ears.

In particular, the combustion apparatus shown in FIG. 23 has a structure in which the exhaust gas flowing into the exhaust stack 108 from below is deflected laterally and exhausted. For this reason, the flow of the exhaust gas is disturbed inside the exhaust stack 108, which causes large noise. In order to reduce the noise in the exhaust stack 108, as shown in FIG. 24, a structure in which a deflecting plate 111 that is curved according to the direction of deflection of exhaust gas is arranged inside the exhaust stack 108 has been developed. . However, even if such a deflecting plate 111 is provided, the effect of suppressing the disturbance of the flow of the exhaust gas is small and the noise is slightly reduced, so that effective measures have been desired. Therefore, the present invention focuses on the above-mentioned problems, and an object thereof is to develop a combustion device capable of reducing noise caused by the flow of exhaust gas (air) in the combustion device and performing silent operation.

[0011]

As a result of intensive studies by the present inventors in order to solve the above-mentioned problems, it has been found that there are roughly two types of noise caused by a blower. That is, one of the noises is the wind noise of the blades generated by the blower itself. Another noise is a passing sound (collision sound) generated when the blown air flow collides with an obstacle in the air flow passage or a portion that deflects the air flow passage when passing through the air flow passage. .

Further, when the noise propagation path was examined, it was found that the wind noise of the blades of the blower 103 leaked to the outside along the above-mentioned secondary air path.
As described above, in the conventional combustion device 100, the partition plate 105 is provided with a large number of ventilation holes, and the ventilation holes 107 are in direct communication with the gaps between the burner members 102. Therefore, in the structure of the prior art, since the ventilation hole of the partition plate 105 is provided in the opening direction of the blower port of the blower 103, and the gap between the burner members 102 communicates linearly, the blower port of the blower 103 is There is nothing to block the leaking sound. Therefore, the noise of the blower 103 directly leaks to the combustion section side, and the heat exchange section 107,
It leaks outside through the exhaust stack 108.

On the other hand, the passing sound generated when the blown air (exhaust gas) passes through the air passage is generated everywhere. Therefore, the present inventors have tried and conducted various measures as much as possible in order to reduce the passing sound of the blown air. As a result, it was discovered that providing a concave or convex shape on the wall surface of the air flow passage significantly reduces noise.

Claim 1 completed based on the above findings
The invention described in (1) has a blower, a combustion unit that injects fuel to generate a flame, and a combustion device that supplies air to the combustion unit from the blower to burn, and includes an exhaust pipe that discharges exhaust gas. Therefore, a part or all of the exhaust pipe is provided with a concave shape or a convex shape.

There are various types of exhaust tubes provided in the combustion apparatus, such as those that directly discharge the exhaust gas without deflecting the flowing direction of the exhaust gas, and those that deflect the flowing direction of the exhaust gas at a right angle. If the flow direction of the exhaust gas is not deflected inside the exhaust stack, the flow of the exhaust gas is less likely to be disturbed, and noise is less generated in the exhaust stack. However, in the case of deflecting the flow direction of exhaust gas inside the exhaust stack,
The flow of the exhaust gas is disturbed due to the deflection, a large eddy current is easily generated, and the concentration of the exhaust gas is apt to be deviated, which leads to an increase in flow path resistance and noise.

In the combustion apparatus of the present invention, the inner wall surface of the exhaust pipe is provided with a concave shape or a convex shape. As a result, the passing noise of exhaust gas is significantly reduced. When the inner wall of the exhaust pipe is provided with a concave or convex shape, the reason why the passing sound is reduced is that the bounce of the flowing exhaust gas is mitigated by the unevenness, and the generation of a large vortex is suppressed. That is, the exhaust gas flowing into the exhaust stack collides with the inner wall of the exhaust stack everywhere. When the inner wall of the exhaust pipe is provided with a concave or convex shape as in the present invention, the exhaust gas collides with the unevenness to generate a small vortex. As a result, the rebound caused by the collision between the exhaust gas and the inner wall is alleviated, the generation of a large vortex is suppressed, and the exhaust gas flows along the inner wall of the exhaust pipe. Therefore, it is considered that noise accompanying the flow of exhaust gas is reduced. The concave shape or the convex shape can be provided at an appropriate portion of the inner wall of the exhaust pipe, but it is particularly effective to provide it at a portion where the flow of exhaust gas is easily disturbed, such as a portion where the flow path is deflected.

Here, the concave shape or the convex shape of the air flow path (exhaust gas flow path) referred to in the present invention means a shape in which only a concave portion is arranged in the flow path or a shape in which only a convex portion (protrusion) is arranged. Alternatively, it includes a shape in which concave portions and convex portions are mixed and arranged. Further, in the concave shape or the convex shape referred to in the present invention,
It also includes a concave shape or a convex shape generated by providing an opening (small hole) in the air flow path (exhaust gas flow path), or a shape in which a mesh member or punching metal is attached to the flow path.

According to a second aspect of the present invention, in the exhaust stack,
A deflecting member for deflecting the flow direction of the exhaust gas is provided, and a part or all of the deflecting member is provided with a concave shape or a convex shape. In the case where the flow direction of the exhaust gas is deflected inside the exhaust pipe, the flow of the exhaust gas is disturbed at the deflected portion. According to the present invention, since the deflecting member having the concave shape or the convex shape is provided, the exhaust gas flows along the deflecting member for the reason described above. As a result, generation of a large vortex is suppressed, and the passing noise of exhaust gas can be reduced. The concave shape or the convex shape can be provided at an appropriate portion of the deflecting member,
Particularly, it is preferable to dispose the deflecting member at a portion where the flow of the exhaust gas is easily disturbed.

According to a third aspect of the present invention, in the exhaust stack,
A deflecting member that deflects the flow direction of the exhaust gas is provided, and an opening is provided in a part or all of the deflecting member. According to the present invention, by providing the deflection member with the opening, the exhaust gas moves to the portion where the pressure of the exhaust gas decreases via the opening. As a result, the pressure of the exhaust gas is made uniform, the generation of a large vortex is suppressed, and the exhaust gas flows along the deflection member. This reduces the generation of noise.

According to a fourth aspect of the present invention, in the exhaust stack,
A draining member for discharging rainwater entering through the exhaust port is provided, and a part or all of the draining member is provided with a concave shape or a convex shape. The draining member is provided inside the exhaust pipe, discharges rainwater that has entered through the exhaust port to the outside, and is formed of a plate body inclined downward to the exhaust port side. Generally, the combustion device is installed outdoors,
Since the exhaust stack is exposed to wind and rain, the draining member is an essential component. However, when the draining member is arranged inside the exhaust stack, the smooth flow of the exhaust gas is obstructed, the exhaust gas collides with the draining member, and local turbulence of the flow is apt to occur, which increases the flow path resistance and noise. Lead to an outbreak.

According to the present invention, by providing the draining member with the concave shape or the convex shape, generation of a large vortex is suppressed in the vicinity of the draining member, and the exhaust gas flows along the draining member, for the reason described above. . Thereby, the passing noise of exhaust gas can be reduced. The concave shape or the convex shape can be provided at an appropriate portion of the draining member, but it is effective to provide it at a portion where the flow of exhaust gas is easily disturbed by disposing the draining member.

According to a fifth aspect of the present invention, in the exhaust stack,
A drainage deflecting member is provided for deflecting the outflow direction of the outflowing exhaust gas while discharging rainwater entering through the exhaust port, and a configuration in which a part or all of the drainage deflecting member is provided with a concave shape or a convex shape It is said that. According to the present invention, the number of members can be reduced by adopting the draining deflecting member having both the function of the deflecting member and the function of the draining member. Further, when the draining deflecting member is provided, the flow passage resistance is increased and the noise is generated. However, by providing the draining deflecting member with the concave shape or the convex shape, the passing sound of the exhaust gas can be reduced for the reason described above. it can. The concave shape or the convex shape can be provided at an appropriate portion of the drainage deflecting member, but it is particularly preferable to provide it at a portion where the flow of exhaust gas is easily disturbed by disposing the drainage deflecting member.

According to a sixth aspect of the present invention, in the exhaust stack,
An lining member is provided along at least part or all of the inner wall surface that deflects the flow direction of the exhaust gas, and a concave shape or a convex shape is provided on part or all of the lining member. There is. As described above, in the portion that deflects the flow direction of the exhaust gas, the flow of the exhaust gas is disturbed and a large vortex is generated, or the concentration of the exhaust gas is apt to be biased, which may increase the flow path resistance or generate noise. Connect

According to the present invention, since the lining member is provided on the inner wall surface for deflecting the flow direction of the exhaust gas, the noise generated inside is doubly shielded by the lining member and the exhaust pipe.
Noise leaking to the outside is reduced. Further, by providing the lining member with the concave shape or the convex shape, it is possible to further reduce the passing noise of the exhaust gas for the reason described above. The concave shape or the convex shape can be provided at an appropriate portion of the lining member, but it is particularly effective to provide it at a portion where the flow of the exhaust gas is disturbed and a large eddy current is easily generated.

The present invention according to claim 7 has a structure in which a soundproof material is attached between the inner wall of the exhaust pipe and the lining member. According to the present invention, the soundproof material suppresses the leakage of the passing sound generated by the flow of the exhaust gas to the outside.
As the soundproof material, a sound insulating material that shields noise, a sound absorbing material that absorbs noise, or the like can be preferably used.

According to the present invention as set forth in claim 8, the exhaust pipe has a box shape in which the lower surface is open and one side is opened as an exhaust port, and is a flat plate-shaped deflecting member or draining member or draining deflecting member. Is arranged substantially horizontally by shielding a part of the lower surface adjacent to the exhaust port, and the exhaust gas flows into the exhaust tube from the unshielded portion of the lower surface of the exhaust tube, And is discharged from the exhaust port.

According to the present invention, a part of the lower surface of the exhaust pipe adjacent to the exhaust port is shielded by either the deflecting member, the draining member or the draining deflecting member. Therefore, the exhaust gas is
It does not flow directly from the lower surface of the exhaust pipe adjacent to the exhaust port to the exhaust port. Therefore, it flows into the exhaust pipe from the unshielded portion of the lower surface of the exhaust pipe, flows laterally inside the exhaust pipe, and reaches the exhaust port. As a result, the flow path length of the exhaust gas in the exhaust stack is equivalently increased as compared with the case where the deflecting member or the like is not provided, and the noise silencing property is improved.

Further, in the present invention according to claim 9, the concave shape or the convex shape has a cylindrical shape, a hemispherical shape, a triangular prism shape, a conical shape,
It is configured to have either a triangular pyramid shape or a burring shape. According to the experiments by the present inventors, the concave shape or the convex shape has the above-mentioned cylindrical shape, hemispherical shape, triangular prism shape, conical shape,
The triangular pyramid shape and burring shape have a high noise prevention effect,
And it was easy to make. In addition, the concave shape or the convex shape referred to in the present invention includes the concave shape or the convex shape generated by the opening by punching.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a combustion apparatus according to an embodiment of the present invention. FIG. 2 is a perspective view of a combustion section of the combustion device of FIG. FIG. 3 is a front view and a plan view of a partition plate used in the combustion apparatus of FIG. FIG. 4 is a perspective view of a burner member used in the combustion apparatus of this embodiment. Figure 5
FIG. 5 is an exploded perspective view of the burner member of FIG. 4. FIG. 6 is an explanatory view showing the flow of fuel gas on the side of the fresh gas flow path in the burner member of FIG. FIG. 7 is an explanatory diagram showing the flow of fuel gas on the rich gas passage side in the burner member of FIG.

In FIG. 1, reference numeral 1 indicates a combustion apparatus of the present invention. The combustion apparatus 1 of the present invention is specifically built in a water heater, and is roughly divided into a blower unit 2, a burner case unit 3, a heat exchange unit 4, and an exhaust unit (exhaust pipe) 5. .

The blower section 2 will be described in order from the lower side.
It is a blower 8 such as a sirocco fan or a turbo fan, and has a structure in which internal blades 11 are rotated by rotation of a motor 10. The blower 8 has an air supply port 12 in the axial direction of the blade 11 and a blower port 13 in the tangential direction of the blade 11.
The blower port 13 of the blower 8 is directly attached to the air introduction port 32 of the burner case 15 described later.

The burner case portion 3 has a box-shaped burner case 15, and a plurality of burner members 35 are incorporated therein. Further, when the burner case portion 3 is functionally subdivided, it is divided into an air flow passage portion 17, a fuel / air mixing portion 18, and a combustion portion 19. In other words, burner case 15
Is a rectangular box, and is a member in which the bottom plate portion 20 and the side surface portion 21 are covered with a plate, and the upper surface side is open. In the present embodiment, the bottom plate portion 20 functions as the first flow path forming wall, and hence this member is hereinafter referred to as the first flow path forming wall 20.

As shown in the figure, the first flow path forming wall 20 is provided with an inwardly projecting protrusion 28 on one surface, and the surface has an uneven shape. The protrusion 28 is hemispherical and has a diameter of 2 to
The height is about 8 mm and the height is 3 mm or less. The protrusion 28 is provided by pressing a plate that constitutes the burner case 15 to make it concave. Further, according to the experiments by the present inventors, in the case of adopting the embodiment of FIGS.
It was confirmed that the effect is great when the height of the protrusion 28 is about 1.2 mm. An air inlet 32 is provided at a position near the end of the first flow path forming wall 20. The air inlet 32 is a square opening.

A partition plate 22 is provided inside the burner case 15. The partition plate 22 is shown in FIGS.
As shown in FIG. More specifically, the partition plate 22 has a flat surface portion 23, and an end portion thereof is vertically raised to provide a first vertical wall portion 26. Further, the end portion of the first vertical wall portion 26 is bent in the horizontal direction, and the end portion thereof is vertically raised to provide a second vertical wall portion 29, and the step portion 25 is formed by these. .

Since the flat surface portion 23 of the partition plate 22 functions as a second flow path forming wall, this member is hereinafter referred to as a second flow path forming wall 23. The second flow path forming wall 23 is also provided with a protrusion 30 protruding outward, and the surface thereof has an uneven shape. The shape of the protrusion 30 is the same as that of the protrusion 28 of the first flow path forming wall 20 described above, and is hemispherical with a diameter of 2
~ 8 mm, its height is 3 mm or less,
A more desirable height is about 1.2 mm. Protrusion 30
Is provided by pressing the plate that constitutes the burner case 15 to make it concave.

On the first vertical wall portion 26 of the step portion 25 of the partition plate 22, there is provided an elongated air intake 31. The partition plate 22 divides the interior of the burner case 15 into two stages, and the second flow path forming wall (flat surface portion) 23 of the partition plate 22 is positioned parallel to the first flow path forming wall 20 of the burner case 15. . Therefore, a gap is formed between the first flow path forming wall 20 and the second flow path forming wall 23. Then, the void functions as the in-box air flow path 33. The second vertical wall portion 29 of the partition plate 22 contacts a part of the side wall of the burner case 15. Therefore, a gap 34 is formed in the step portion of the partition plate 22.

The burner member 35 is placed on the partition plate 22.
Are arranged side by side. Here, the burner member 35 includes a burner body 36 and a flame hole member 37. As shown in FIG. 5, the burner body 36 is made by stacking four metal plate bodies, and air or fuel gas flow paths are formed between the plate bodies. In other words, the burner main body 36 is the main constituent body 4 in which the two central plate bodies are combined.
2 and auxiliary components 44 on both sides thereof.

Explaining the external appearance of the burner member 35, there are two upper and lower openings 38, 39 at the lower end. And the opening at the upper part thereof is a gas introduction port 38 through which the fuel gas is introduced together with air. On the other hand, the lower opening 39 is an air introduction port into which only air is introduced.

The burner member 35 used in this embodiment is
It is a burner of the rich and lean combustion type, and a lean fuel gas is emitted from the flame hole member 37, and a high-concentration combustion gas is emitted from the periphery thereof. That is, inside the burner member 35, there are two systems of fuel gas flow paths. More specifically, there is a flow path inside the main constituent body 42 in the center and a flow path constituted by the side surfaces of the main constituent body 42 and the auxiliary constituent bodies 44 on both sides. Most of the fuel gas introduced from the gas inlet 38 is discharged to the outside from the flame hole member 37 via the path shown in FIG. During this time, the fuel gas is mixed with the air introduced from the air inlet 39 and is diluted.

On the other hand, the rest of the fuel gas introduced from the gas inlet 38 is discharged from the periphery of the flame hole member 37 via the path shown in FIG.

The burner member 35 is the partition plate 22.
Are arranged side by side on top of each other, and a fuel / air mixing unit 18 is configured. Further, the gas introduction port 38 and the air introduction port 39 of the burner member 35 coincide with the air intake port 31 of the partition plate 22. A fuel nozzle 41 is provided near the gas inlet 38 of the burner member 35.

That is, the burner case portion 3 employed in the combustion apparatus 1 is provided with the fuel / air mixing portion 18 above the partition plate 22 as described above, and the fuel / air mixing portion 18 separates the fuel and air from each other. Pre-mixed. Further, the first flow passage forming wall 20 is provided with an air introduction port 32 for introducing the air blown from the blower 8, and further the fuel / air mixing portion 18 and the first flow passage forming wall 2 are provided.
The second flow path forming wall 23 is provided between 0, and the in-box air flow path 3 is formed by the first flow path forming wall 20 and the second flow path forming wall 23.
3 is formed. An air intake 31 for introducing air into the fuel / air mixing portion 18 is provided at a position near the end of the burner case 15. An air inlet 32 for introducing air from the blower 8 and an air inlet 31 for introducing air to the fuel / air mixing portion 18 are located close to both ends of the burner case 15.

Next, the heat exchange section 4 will be described. The heat exchange section 4 is a rectangular cylinder through which combustion gas passes. The cylindrical body of the heat exchange section 4 and the burner case 15 are in communication with each other. Inside the heat exchange section 4, a large number of fins 40a are vertically arranged at predetermined intervals, and a bent hot water supply pipe 40b is attached so as to penetrate the fins 40a. Then, when the combustion gas rises, the heat of the combustion gas is heat-exchanged with the hot water supply pipe 40b via the fins 40a, and the heat-exchanged combustion gas flows downstream as exhaust gas.

An exhaust stack 5 is provided on the downstream side of the heat exchange section 4. The exhaust pipe 5 discharges the exhaust gas rising from the heat exchange section 4 by laterally deflecting the flow direction thereof, and has a box shape with an open left side. The exhaust cylinder 5 is configured to include an exhaust outer cylinder 43, an inner lining member 46, a draining deflection member 48, and the like.

Here, the detailed structure of the exhaust pipe 5 will be described with reference to the assembly process drawing and the member drawings. FIG. 8 is a perspective view showing a first assembling step of the exhaust stack of the combustion apparatus shown in FIG. FIG. 9 is a perspective view showing the second assembling process of the exhaust stack. FIG. 10 is a perspective view of the lining member. FIG. 11 is a perspective view of the drain deflector. FIG. 12 is a perspective view showing a third assembly process of the exhaust stack. FIG. 13 is a perspective view showing the appearance of the assembled exhaust stack. FIG. 14 is a cross-sectional view of the exhaust stack shown in FIG. FIG. 15A is an explanatory view schematically showing the structure of the combustion section of FIG. 2, FIG. 15B is an enlarged view in a circle of FIG. 15A, and FIG. 15C is related to a comparative example. It is an enlarged view of a circle. In the following description, the up / down, left / right, and front / rear directions are based on the state in which the exhaust stack 5 is attached to the combustion device 1 as shown in FIG.

In the first assembling process of the exhaust pipe 5, as shown in FIG. 8, the soundproof material 47 is inserted into the exhaust outer pipe 43. The exhaust outer cylinder 43 is made by press molding of a metal plate or a die casting method, and has a top surface portion 43a and side surface portions 43b, 4b.
It has 3b and 43c, and the lower part and the left side of the drawing are opened. The left open portion functions as the exhaust port 45. The top surface portion 43a is slightly inclined downward near the exhaust port 45, and the open end of the top surface portion 43a is bent upward to form a flange portion 43e. Further, the lower edges of the side surface portion 43b and the side surface portion 43c are once bent outward and then bent downward again to form a flange portion 43d. Further, two cylindrical locking projections 43f for positioning and fixing an inner lining member 46, which will be described later, are provided on the inner surfaces of the side surfaces 43b, 43b of the exhaust outer cylinder 43, which face each other. In the first assembling step, as shown in FIG. 8, a soundproof material (sound absorbing material) 47 made of glass wool or the like is inserted into the exhaust outer cylinder 43. The soundproof material 47 is provided in the exhaust port 4
It is bent and inserted along the surface portion extending from the top surface portion 43a near the 5 side to the side surface portion 43c.

In the second assembling process of the exhaust pipe 5, as shown in FIG. 9, the lining member 46 is attached to the exhaust outer pipe 43 in which the soundproof material 47 is inserted. The lining member 46 is shown in FIG.
As shown in FIG. 10, it is made by punching and bending a thin metal plate by a press method, and has a shape along the top surface portion 43a and the side surface portion 43c of the exhaust outer cylinder 43. That is, the lining member 46 has a planar upper surface portion 46a, a side surface portion 46b, and a flange portion 46d, and along the top surface portion 43a and the side surface portion 43c of the exhaust pipe 5,
The upper surface portion 46a and the side surface portion 46b are slightly bent. Further, a part of both front and rear edges of the upper surface portion 46a is bent downward to form a pair of bent portions 46e, 46e, and a lower edge of the side surface portion 46c is bent rightward (outward). It is bent to form a flange portion 46c.

Here, the bent portion 46e has bent curved surfaces 46f and 46f formed by bending the front and rear side edges of the upper surface portion 46a so as to hang down.
The lower edges of f and 46f are bent in the front-rear direction (outside) to form flange portions 46g and 46g. Also, the curved surface 4
Part of the left and right side edges of 6f and 46f is once bent in the front-rear direction (outside) and then in the left-right direction (exhaust port 45 side) to form bent portions 46i and 46k having an L-shaped cross section. Is forming. Engaging portions 46j and 46m, which are cut out in a semicircular shape, are provided at the tips of the bent portions 46i and 46k. Also,
The folding curved surfaces 46f, 46f are provided with fitting portions 46h, 46h that are cut out with a predetermined width from the left side edge toward the right side. The fitting portions 46h, 46h will be described later in detail.
The drain deflector 48 is fitted.

Further, a large number of projections (convex shapes) 46p and small holes 46q (concave shapes) are mixedly provided on a part of the upper surface portion 46a and the side surface portion 46b of the lining member 46. The shape of the hemispherical projection 46p is the same as that of the projections 28 and 30 provided on the first flow path forming wall 20 and the second flow path forming wall 23 of FIG. That is, the diameter of the protrusion 46p is about 2 to 8 mm, and the height thereof is 3 mm or less. The most recommended height of the protrusion 46p is about 1.2 mm. The diameter of the small holes 46q is about 5 to 10 mm.

In the second assembling step, as shown in FIG. 9, the bent portions 46e of the lining member 46 are pressed so as to be close to each other, while the sound proof member 47 is pressed by the lining member 46 to exhaust the air. Insert into the outer cylinder 43. And the lining member 4
6 engage the engaging portions 46j and 46m with the locking projection 4 of the exhaust outer cylinder 43.
The pressure is released while aligned with 3f. As a result, the lining member 46 is fixed to the exhaust outer cylinder 43 while being positioned. In the state where the lining member 46 is fixed to the exhaust outer cylinder 43, the soundproofing material 4 is inserted through the small holes 46q of the lining member 46.
Part of 7 is exposed. In this embodiment, after the inner lining member 46 is positioned and fixed to the exhaust outer cylinder 43, the flange portions 46c and 46g of the inner lining member 46 and the flange portion 43d of the exhaust outer cylinder 43 are spot welded at appropriate intervals. (See spot weld S in FIG. 12).

In the third assembly step, as shown in FIG.
The draining deflecting member 48 is fitted into the lining member 46 fixed to the exhaust outer cylinder 43. As shown in FIG. 11, the draining deflecting member 48 is formed by folding back a thin metal plate. That is, the lower deflecting flat portion 48a and the upper draining portion 48b are connected to each other at the folded portion to be integrally formed, and the folded portion is curved to form the deflecting portion 48c. The deflecting portion 48c has a large radius, and in the present embodiment, in addition to having a function of positioning the draining deflecting member 48, a step near the portion prevents rainwater from entering. Deflection plane part 48
The lower surface of a has a substantially hemispherical protrusion 4 protruding downward.
Many 8e are arranged. The shape of the protrusion 48e is
It has the same shape as the projection 46p provided on the lining member 46, the diameter of the hemisphere is about 2 to 8 mm, and its height is 3 mm.
It is the following. The most recommended height of the protrusion 48e is 1.2.
It is about mm. Further, the left side edge of the deflection plane portion 48a is bent downward to form a flange portion 48d, and the front and rear side edges of the deflection plane portion 48a are bent upward to form a reinforcing portion 48f. ing.

In the third assembly process, as shown in FIG.
The deflecting portion 48c of the draining deflecting member 48 is press fitted into the fitting portion 46h of the lining member 46. The deflecting portion 48c of the draining deflecting member 48 has elasticity because the thin metal plate is curved.
Therefore, the deflection portion 48c fitted in the fitting portion 46h is slightly elastically deformed and is sandwiched by the fitting portion 46h. As a result, the draining deflecting member 48 is positioned and fixed to the lining member 46.

When the third assembling step is completed, the exhaust stack 5 is completed as shown in FIG. Assembled exhaust stack 5
Is the flange portion 46d of the lining member 46 and the draining deflecting member 4
No. 8 flange portion 48d and the flange portion 48d are flush with each other, and the exhaust port 45 is formed between the flange portion 46d and the flange portion 48d. The exhaust top 64 shown in FIG. 1 is attached and fixed to the flange portion 46d of the lining member 46 and the flange portion 48d of the draining deflecting member 48. As a result, the drainage deflecting member 48 is firmly positioned and fixed on the exhaust port 45 side without moving vertically.

FIG. 14 is a sectional view showing the exhaust pipe 5 assembled in this manner.
The same components as those in No. 3 are designated by the same reference numerals. As can be seen from the figure, the draining deflecting member 48 of the exhaust stack 5 has a double structure and has a substantially triangular wing shape. In addition, the deflection unit 48
c has a large radius. Further, the draining deflecting member 48 of the exhaust stack 5 is fixed in a state in which it is slightly inclined downward toward the exhaust port 45 side. As a result, the rainwater entering from the exhaust port 45 flows leftward along the water drainage portion 48b and is discharged to the outside. The draining deflecting member 48 has a gentle slope from the exhaust port 45 to the draining portion 48b, but has a large step portion 48f at a position from the draining portion 48b to the deflecting portion 48c. Therefore, the rainwater that has entered from the exhaust port 45 is dammed by the step portion 48f, the step portion 48f functions as a rainwater stopper, and does not enter the heat exchange unit 4 or the like.

Next, the operation of the combustion apparatus 1 of this embodiment will be described. In the combustion device 1 of the present embodiment, as shown in FIG. 1, water is passed through the heat exchanger 40, the blower 8 is started, and further fuel gas is discharged from the fuel nozzle 41, and the flame hole member 37 of the burner member 35 and The fuel gas emitted from the surroundings is ignited. Here, in the combustion device 1 of the present embodiment, the flow of air from the heat exchange section 4 through the exhaust stack 5 to the exhaust port 45 is important. However, in the combustion device 1 of the present embodiment, a structure that suppresses noise is also applied to the air flow path from the blower 8 to the heat exchange unit 4, and thus the detailed description will be given below step by step.

In other words, in the combustion apparatus 1 of this embodiment, the air blown by the air blower 8 is introduced into the burner case 15 through the air inlet 32. Then, the air flow hits the second flow path forming wall 23, changes its direction to the horizontal direction, and flows through the in-box air flow path 33. Here, the projection 2 is formed on the first flow passage forming wall 20 and the second flow passage forming wall 23 that form the in-box air flow passage 33.
Since it is the uneven shape in which 8 and 30 are provided, a minute vortex is generated, and the first flow path forming wall 20 and the second flow path forming wall 23 are formed.
The flow is difficult to separate from the surface. As a result, the air flow is rectified and the noise generated is reduced.

In other words, when the protrusions 28 and 30 do not exist, the air blower 8 blows the first flow passage forming wall 20 and bounces off the second flow passage forming wall 23 as shown in FIG. 15C. Further, the blast is applied to the second flow path forming wall 23
Bounced by. When the protrusions 28 and 30 do not exist in this manner, it is considered that the blown air is in a violent turbulent state and flows downstream, resulting in a large amount of noise. On the other hand, in this embodiment, small vortices are generated by the protrusions 28 and 30 as shown in FIG. 16, and the rebound from the wall surface is suppressed as shown in FIG. 15B. Therefore, noise is reduced.

The air flowing through the in-box air flow path 33 reaches the void portion 34 at the end and enters the fuel / air mixing portion 18 from the elongated air intake 31 provided in the partition plate 22. In the combustion device 1 of the present embodiment, the burner member 35
Is a burner of a rich-lean burn type, and the fuel gas discharged from the flame hole member 37 is mixed with air exceeding the theoretical air amount. Therefore, in this embodiment, all the air used for combustion is supplied from the air intake port 31 to the fuel / air mixing unit 1.
Introduced in 8.

In other words, in the present embodiment, the air enters the burner member 35 in the fuel / air mixing portion 18 via the elongated air intake 31. More specifically, the gas enters the gas inlet 38 and the air inlet 39 of the burner member 35, is mixed with the fuel gas, and is discharged from the flame hole member 37 and its surroundings. Then, the fuel gas burns, and the heat exchange section 4
To reach the exhaust stack 5 as exhaust gas.

Exhaust gas flows into the exhaust stack 5 from below in a substantially vertical upward direction. Therefore, as shown by the arrow in FIG. 14, the inflowing exhaust gas collides with the deflecting flat surface portion 48 a of the water draining deflecting member 48 and concentrates on the right side of the exhaust pipe 5. Then, while being deflected by the side surface portion 46 b of the lining member 46, the upper surface portion 46
It flows to the left along a and is discharged from the exhaust port 45.
Further, in the present embodiment, since the deflecting portion 48c has a large radius, in the exhaust pipe 5, the bending angle of the portion where the exhaust gas flow path is sharply bent becomes gentle, and the turbulence of the wind is reduced to reduce the turbulence of the portion. The generated sound is reduced. Further, in this embodiment, since the deflection portion 48c has a large radius, the exhaust port 4
The turbulence of the exhaust gas guided to the No. 5 side is also small, and the generated sound is further reduced. Further, in this embodiment, when the exhaust gas flows into the exhaust stack 5, as described above, the exhaust gas collides with the deflecting flat surface portion 48a of the draining deflecting member 48. However, since the deflection plane portion 48a is provided with the convex protrusion 48e, the protrusion 2 is formed on the first flow path forming wall 20 shown in FIG.
Similar to the case where 8 is provided, rebound is suppressed, large vortices are not generated, and noise is reduced.

The exhaust gas flowing into the exhaust pipe 5 along the draining deflecting member 48 collides with the lining member 46 and flows while being deflected. However, as described above, the protrusion 46p having a convex shape is also formed on the side surface portion 46b and the upper surface portion 46a of the lining member 46.
Is provided. As a result, rebound is suppressed and noise generation is reduced. Further, as shown in FIG. 10, the lining member 46 is provided with a large number of small holes 46q, and a part of the noise generated in the exhaust pipe 5 is transmitted through the small holes 46q through a soundproof material (sound absorbing material). ) Is absorbed. This further reduces noise. Further, in the exhaust pipe 5 of the present embodiment, as shown in FIGS. 1 and 14, by disposing the draining deflecting member 48 inside the exhaust pipe 5, the drain pipe 5 is moved from the left side of the heat exchange portion 4 to the exhaust pipe 5. The exhaust gas that has flowed in is not directly exhausted from the exhaust port 45. In other words, the exhaust gas flow path length until the exhaust gas flowing into the exhaust pipe 5 reaches the exhaust port 45 is equivalently increased, whereby the soundproof effect is further improved. Further, in the present embodiment, the drainage deflecting member 4
Reference numeral 8 denotes a deflecting flat surface portion 48a on the lower surface side and a draining portion 48 on the upper surface side
Since it has a double structure of b, there is also an effect that noise of the blower part 2 and the like is hard to escape to the upper side.

The inventors of the present invention made a prototype of the combustion apparatus 1 of the above-described embodiment and a combustion apparatus having no protrusion, and compared the noises of the two. As a result, an average noise reduction of 1 dB was observed in the range of 100 Hz to 2000 Hz. confirmed. here,
When the combustion device 1 is prototyped, the lining member 46, the drainage deflecting member 48, the first flow path forming wall 20, and the second flow path forming wall 2
The hemispherical projection (convex shape) provided in 3 has a diameter of 2 to 8 mm.
And the height were variously changed within a range of 3 mm or less.
As a result, it was confirmed that the noise suppressing effect is high when the protrusion has a diameter of 2 to 8 mm and the protrusion has a height of about 1.2 mm.

In the embodiments described above, the hemispherical shape is shown as the shape of the protrusion, but the present invention is not limited to this shape and any other shape can be adopted. In addition to the above-mentioned hemispherical shape, the recommended shape of the projection is a burring-shaped projection 55 as shown in FIG. However, in the burring shape, the air leaks from the central hole 52 and the noise of the blower 8 escapes to the combustion section 19 side, so the back plate 5 for closing the hole 52.
It is desirable to provide 3.

Further, a triangular columnar projection 56 as shown in FIG. 18 is also recommended. Although the triangular column-shaped projection 56 is somewhat difficult to process, it has a high function of generating a small vortex and has a high effect of reducing noise.

Further, as shown in FIG.
Also has a high function of generating a small vortex and is highly effective in reducing noise.

In all of the above constructions, the member forming the air flow path is provided with a concave shape or a convex shape, but another member may be attached to the surface of the air flow path to form the unevenness. Recommended. For example, a mesh or a punching metal may be attached to the surface of the air flow path to form irregularities on the surface of the air flow path. In addition, when the flow velocity of air (exhaust gas) is faster, it is confirmed that the effect of reducing noise is high by processing the inner surface of the air flow passage (exhaust flow passage) with a rough shape like sand paper. Was done.

In the above-described embodiment, the drainage deflecting member 48 is provided.
Is a thin metal plate folded back to form a deflection plane portion 48a on the lower surface side,
Although the inside has a double structure having the drainage portion 48b on the upper surface side and the inside is hollow, the inside may have a solid structure. That is, it may be formed into a substantially triangular shape by using metal, resin, ceramic or the like. Further, the combustion device 1 of the above embodiment
In the above, the exhaust cylinder 5 is configured to include the exhaust outer cylinder 43, the lining member 46, and the draining deflecting member 48, but the present invention is not limited to such a structure. Figure 20 ~
FIG. 22 shows a modified embodiment of the exhaust stack 5.

FIG. 20 (a) is a sectional view showing an exhaust pipe 5 of a modified embodiment of the present invention, and FIG. 20 (b) is an enlarged view of the inside of a circle of FIG. 20 (a). In the present embodiment, the exhaust pipe 5 is configured to include the exhaust outer pipe 43, the draining member 60, and the deflecting member 61, and has a simplified structure in which the lining member is not provided. In this example, the deflecting member 61 has a shape in which a metal flat plate is curved in a substantially U shape, and a protrusion (convex shape) 6 is formed on a part of the outer surface of the curved portion.
Many 1a are arranged. The protrusion 61a is similar to the protrusion 48e of the draining deflecting member 48 shown in FIG. The draining member 60 has a simplified structure in which the draining portion 48b of the draining deflecting member 48 shown in FIG. 11 is removed and the projection 48e of the deflecting flat portion 48a is removed.

In this embodiment, the deflecting section 6 of the draining member 60 is used.
Deflection members 61 are arranged at a predetermined interval so as to enclose 0a. In this configuration, the exhaust gas flowing near the deflecting member 61 collides with the protrusion 61a to generate a small vortex, and the generation of a large vortex is suppressed. As a result, the exhaust gas is suppressed from being separated from the deflection member 61, and the generation of noise is reduced.

FIG. 21 (a) is a sectional view showing an exhaust pipe 5 according to another modified embodiment of the present invention, and FIG. 21 (b) is (a).
It is an enlarged view of a circle. In the present embodiment, the exhaust cylinder 5 is configured to include the exhaust outer cylinder 43, the draining member 60, and the deflecting member 62. In this example, the deflecting member 62 has a shape similar to that of the deflecting member 61 shown in FIG. 20, but instead of the protrusion, an opening 62a is provided at the center of the curved portion of the deflecting member 62. The draining member 60 has the same structure as that shown in FIG.

According to the present embodiment, the exhaust gas moves through the opening 62a of the deflecting member 62 (see the arrow in FIG. 21 (b)), so that the exhaust gas flows to the portion where the pressure of the exhaust gas decreases. be able to. Thereby, the pressure of the exhaust gas is made uniform, the generation of a large vortex is suppressed, and the exhaust gas flows along the deflection member 62, so that the generation of noise can be effectively suppressed. That is, it is possible to suppress the generation of vortices and suppress noise by supplying exhaust gas to a portion having a low pressure.

FIG. 22 (a) is a sectional view showing an exhaust pipe 5 of still another modified embodiment of the present invention, and FIG. 22 (b) is an enlarged view of a circle in (a). In the present embodiment, the exhaust stack 5
Is an extremely simplified structure composed of the exhaust outer cylinder 43 and the draining member 63. In this example, the draining member 63 is shown in FIG.
Although the shape is similar to that shown by 0, the deflection portion 63a
A large number of protrusions 63b are arranged on the bottom. This protrusion 63b
Is similar to the protrusion 61a of the deflecting member 61 shown in FIG.

According to the present embodiment, the exhaust gas flowing in the vicinity of the deflecting portion 63a of the draining member 63 collides with the protrusion 63b to generate a small vortex, which suppresses the generation of a large vortex. As a result, the exhaust gas is suppressed from being separated from the deflecting portion 63a, and the generation of noise is reduced.

[0074]

According to the present invention described in claim 1, the exhaust pipe has a simple structure in which a concave shape or a convex shape is provided,
It is possible to provide a combustion device that can suppress the generation of a large vortex of exhaust gas, effectively suppress noise, and improve quietness. According to the present invention as set forth in claim 2 or 3, due to the simple structure in which the deflection member having the concave shape, the convex shape or the opening is arranged inside the exhaust pipe, the generation of noise accompanying the flow of the exhaust gas is effective. Can be suppressed. Claim 4
According to the present invention described in (1) above, noise due to the flow of exhaust gas can be effectively suppressed by a simple structure in which a draining member having a concave shape or a convex shape is arranged inside the exhaust pipe. According to the fifth aspect of the present invention, by integrating the draining member and the deflecting member, it is possible to reduce the number of members and effectively suppress noise accompanying the flow of exhaust gas. According to the present invention as set forth in claim 6, the generation of noise due to the flow of exhaust gas is effectively reduced by the simple structure in which the lining member having a concave shape or a convex shape is provided inside the exhaust stack. Can be made. According to the present invention described in claim 7, by providing the soundproof material, the noise generated inside the exhaust stack is suppressed from leaking to the outside, and the quietness is further improved. According to the present invention described in claim 8, it is possible to equivalently lengthen the flow path length of the exhaust gas, and it is possible to provide an exhaust stack with improved sound deadening. Further, according to the present invention described in claim 9, it is possible to adopt an uneven shape having a large noise reduction effect based on an experiment, which facilitates manufacturing.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a combustion device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional perspective view of a blower section and a burner case section of the combustion apparatus of FIG.

3A and 3B are a front view and a plan view of a partition plate used in the combustion apparatus of FIG.

FIG. 4 is a perspective view of a burner member used in the combustion apparatus of FIG.

5 is an exploded perspective view of the burner member shown in FIG.

6 is an explanatory view showing the flow of fuel gas on the side of the fresh gas flow path in the burner member shown in FIG.

FIG. 7 is an explanatory diagram showing the flow of fuel gas on the rich gas passage side in the burner member shown in FIG.

8 is a perspective view showing a first assembly process of an exhaust stack used in the combustion device shown in FIG. 1. FIG.

9 is a perspective view showing a second assembling step of the exhaust stack of the combustion apparatus shown in FIG.

10 is a perspective view showing an inner lining member used in the exhaust stack of the combustion apparatus shown in FIG.

11 is a perspective view showing a draining deflecting member used in the exhaust stack of the combustion apparatus shown in FIG.

12 is a perspective view showing a third assembling step of the exhaust stack of the combustion apparatus shown in FIG.

13 is a perspective view showing an external appearance of an exhaust stack of the combustion apparatus shown in FIG.

14 is a cross-sectional view showing the internal structure of the exhaust stack shown in FIG.

15A is an explanatory view schematically explaining the combustion structure of the combustion apparatus shown in FIG. 2, FIG. 15B is an enlarged view of a circle in FIG.
(C) is an enlarged view in a circle in the comparative example of (a).

16 is an explanatory diagram showing the flow of air in the uneven portion of the combustion device shown in FIG.

FIG. 17 is a diagram of a combustion apparatus according to a modified embodiment of the present invention.
It is an enlarged view corresponding to (b).

FIG. 18 is an explanatory view showing the air flow in the uneven portion of the combustion device according to another modified embodiment of the present invention.

FIG. 19 is an explanatory view showing the flow of air in the uneven portion of the combustion device according to still another modified embodiment of the present invention.

20A is a cross-sectional view showing the structure of an exhaust stack of a combustion apparatus according to another embodiment of the present invention, and FIG. 20B is an enlarged view of a circle in FIG. 20A.

FIG. 21 (a) is a sectional view showing the structure of an exhaust stack of a combustion apparatus according to still another embodiment of the present invention, and FIG. 21 (b) is (a).
It is an enlarged view of a circle.

22 (a) is a sectional view showing the structure of an exhaust stack of a combustion apparatus according to still another embodiment of the present invention, and FIG. 22 (b) is (a).
It is an enlarged view of a circle.

FIG. 23 is a cross-sectional view showing the structure of a combustion device incorporated in a conventional water heater.

FIG. 24 is a cross-sectional view showing the internal structure of an exhaust stack used in another conventional combustion apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Combustion device 3 Combustion part (burner case part) 5 Exhaust pipe 46 Lining member 46p, 48e, 61a, 63b Concave shape, convex shape (projection) 46q Concave shape, convex shape (opening) 48 Draining deflection member 61, 62 Deflection member 62a Opening (opening of deflecting member) 60, 63 Draining member 47 Soundproof material 55 Burring 56 Triangular prism 8 Blower

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yutaka Kawaguchi             93 Edo-cho, Chuo-ku, Kobe-shi, Hyogo Stock Association             Company Noritsu (72) Inventor Kei Hasegawa             93 Edo-cho, Chuo-ku, Kobe-shi, Hyogo Stock Association             Company Noritsu (72) Inventor Koji Shimomura             93 Edo-cho, Chuo-ku, Kobe-shi, Hyogo Stock Association             Company Noritsu F-term (reference) 3K070 AB01 AB13 AB18

Claims (9)

[Claims] 1. A combustion apparatus having a blower and a combustion section for injecting fuel to generate a flame, and for supplying air from the blower to the combustion section for combustion, including an exhaust stack for discharging exhaust gas. A combustion device, wherein a part or all of the exhaust stack is provided with a concave shape or a convex shape. 2. The exhaust stack is provided with a deflecting member for deflecting a flow direction of the exhaust gas, and a part or all of the deflecting member is provided with a concave shape or a convex shape. The combustion device according to Item 1. 3. The exhaust member is provided with a deflecting member for deflecting a flow direction of exhaust gas, and an opening is provided in a part or all of the deflecting member. Combustion device. 4. The drain pipe is provided with a draining member for draining rainwater entering through the exhaust port, and a part or all of the draining member is provided with a concave shape or a convex shape. The combustion apparatus according to any one of claims 1 to 3. 5. A drainage deflecting member for discharging rainwater entering through an exhaust port and deflecting a flow direction of exhaust gas is provided in the exhaust stack, and a part or all of the drainage deflecting member is provided. The combustion device according to claim 1, wherein a concave shape or a convex shape is provided in the. 6. The exhaust pipe is provided with a lining member along at least a part or the whole of an inner wall surface for deflecting the flow direction of the exhaust gas, and the lining member has a concave part or a whole. The combustion device according to any one of claims 1 to 5, wherein a shape or a convex shape is provided. 7. The combustion apparatus according to claim 6, wherein a soundproof material is attached between the inner wall of the exhaust stack and the lining member. 8. The exhaust pipe has a box shape with an open bottom surface and one side opening as an exhaust port, and one of a flat plate-shaped deflecting member, a water draining member, or a water draining deflecting member is used as the exhaust gas. The part of the lower surface that is close to the mouth is shielded and is arranged substantially horizontally, and the exhaust gas flows into the exhaust cylinder from the unshielded portion of the lower surface of the exhaust cylinder and flows laterally inside the exhaust cylinder. The combustion device according to claim 1, wherein the combustion device is discharged through an exhaust port. 9. The concave shape or the convex shape is any one of a cylindrical shape, a hemispherical shape, a triangular prism shape, a conical shape, a triangular pyramid shape, and a burring shape. The combustion apparatus according to item 1.