JP2016048149A

JP2016048149A - Combustion apparatus

Info

Publication number: JP2016048149A
Application number: JP2014173485A
Authority: JP
Inventors: 卓史小代; Takuji Koshiro; 真伍杉岡; Shingo Sugioka
Original assignee: Rinnai Corp
Current assignee: Rinnai Corp
Priority date: 2014-08-28
Filing date: 2014-08-28
Publication date: 2016-04-07
Anticipated expiration: 2034-08-28
Also published as: JP6023133B2

Abstract

PROBLEM TO BE SOLVED: To reduce exhaust resistance and sufficiently reduce resonance noise in a combustion apparatus that includes a laterally long box-shaped exhaust duct 8 connected to an upper portion of a front surface of a combustion case with a built-in burner and in which a laterally long and narrow inflow port 81 having combustion exhaust gas made to flow in from the burner is formed on a rear surface portion of an exhaust duct and the combustion exhaust gas is discharged forwards from an outflow port 82 arranged at a center in the lateral direction of the front surface portion of the exhaust duct.SOLUTION: An exhaust duct 8 includes a laterally long cover 83 that has a U-shaped cross section and that includes a front plate portion 83a located on the front side of an inflow port 81 and upper and lower plate portions 83b, 83c extended rearwards from both upper and lower edges of the front plate portion and reaching upper and lower portions of the inflow port 81 of the rear surface portion of the exhaust duct 8. A large number of through holes 83d are formed on the upper and lower plate portions 83b, 83c of the cover 83, and preferably, a large number of through holes 83d are formed also in the front plate portion 83d.SELECTED DRAWING: Figure 3

Description

本発明は、バーナを内蔵する燃焼筐と、燃焼筐内に燃焼用空気を供給するファンと、燃焼筐の上部前面に接続された横方向に長手の箱形の排気ダクトとを備え、排気ダクトの後面部に、バーナの燃焼排ガスが流入する横方向に細長い形状の流入口が形成され、排気ダクトの前面部の横方向中央部に設けられた流出口から燃焼排ガスが前方に排出されるようにした燃焼装置に関する。 The present invention includes a combustion casing with a built-in burner, a fan for supplying combustion air into the combustion casing, and a box exhaust duct that is horizontally long and connected to the upper front surface of the combustion casing. A laterally elongated inflow port through which the burner flue gas flows in is formed on the rear surface portion, so that the flue gas is discharged forward from an outflow port provided in the lateral center of the front portion of the exhaust duct. The present invention relates to a combustion apparatus.

燃焼筐及び排気ダクトを備える燃焼装置では、ヘルムホルツ型の共鳴を生ずる。その共鳴周波数ｆは、燃焼筐の内容積をＶ、排気経路の最小断面積をＳ、排気経路の長さをＬ、音速をＣとして、
ｆ＝（Ｃ／２π）{Ｓ／（Ｖ・Ｌ）}^１／２…（１）
になる。そして、共鳴周波数がバーナの燃焼振動の周波数に近いと、共鳴による騒音を生ずる。従って、騒音を低減するには、共鳴周波数を燃焼振動周波数からずらすことが必要になる。 A combustion apparatus having a combustion housing and an exhaust duct produces Helmholtz-type resonance. The resonance frequency f is V, the internal volume of the combustion housing, S is the minimum cross-sectional area of the exhaust path, L is the length of the exhaust path, and C is the speed of sound.
f = (C / 2π) {S / (V · L)} ^1/2 (1)
become. When the resonance frequency is close to the combustion vibration frequency of the burner, noise due to resonance is generated. Therefore, to reduce noise, it is necessary to shift the resonance frequency from the combustion vibration frequency.

従来、上記の如く後面部に横方向に細長い形状の流入口が形成され、前面部の横方向中央部に流出口が設けられた排気ダクトを備える燃焼装置において、共鳴による騒音を低減するため、流入口の横方向中央部を覆う邪魔板を設けたものが知られている。このものでは、流入口の横方向中央部の燃焼排ガスが流入口の横方向両側部に迂回して排気ダクト内に流入してから、横方向中央部の流出口に流れることになる。これにより、上記（１）式のＬが大きくなると共にＳが小さくなり、共鳴周波数が燃焼振動周波数よりも小さくなって、共鳴による騒音が低減される。 Conventionally, in a combustion apparatus including an exhaust duct in which a laterally elongated inflow port is formed in the rear surface portion as described above and an outflow port is provided in the lateral center portion of the front surface portion, in order to reduce noise due to resonance, What provided the baffle plate which covers the horizontal center part of an inflow port is known. In this case, the combustion exhaust gas at the central portion in the lateral direction of the inflow port bypasses both lateral portions of the inflow port and flows into the exhaust duct, and then flows into the outlet port at the central portion in the lateral direction. As a result, L in the above equation (1) increases and S decreases, the resonance frequency becomes lower than the combustion vibration frequency, and noise due to resonance is reduced.

然し、このものでは、流入口の実質的な面積が邪魔板により狭められるため、排気抵抗が大きくなり、所要量の燃焼用空気を供給するのに必要なファンの回転数が高くなり、ファン騒音が大きくなってしまう。 However, in this case, since the substantial area of the inlet is narrowed by the baffle plate, the exhaust resistance is increased, the number of fan rotations required to supply the required amount of combustion air is increased, and the fan noise is increased. Will become bigger.

ところで、従来、後面部に円形の流入口が設けられると共に、横方向一方の端面に流出口が設けられた横長の排気ダクトを備える燃焼装置において、排気ダクト内を後側と前側の２つの排気通路部に仕切る仕切り板を設け、各排気通路部の横方向に直交する断面積は流入口の開口面積より小さくし、排気ダクトの横方向他方の端面を閉塞する端板部と仕切り板の横方向他方の端縁との間に後側と前側の排気通路部を連通する通気間隙を設けて、排気抵抗を増加させずに、共鳴周波数を小さくすることができるようにしたものが知られている（特許文献１参照）。 By the way, in a conventional combustion apparatus having a horizontally long exhaust duct having a circular inlet at the rear surface portion and an outlet at one end face in the lateral direction, the exhaust duct has two exhausts on the rear side and the front side. A partition plate for partitioning the passage portion is provided, the cross-sectional area perpendicular to the lateral direction of each exhaust passage portion is made smaller than the opening area of the inlet, and the end plate portion that blocks the other end surface in the lateral direction of the exhaust duct and the side of the partition plate It is known that a ventilation gap that communicates the rear and front exhaust passages between the other end in the direction is provided so that the resonance frequency can be reduced without increasing the exhaust resistance. (See Patent Document 1).

本願発明者は、この仕切り板の技術を利用し、後面部に横方向に細長い形状の流入口が形成され、前面部の横方向中央部に流出口が設けられた排気ダクトを備える燃焼装置において、排気ダクト内に、流入口の前方に位置する前板部と、前板部の上下両縁から後方にのびて排気ダクトの後面部の流入口の上方部分及び下方部分に達する上下の板部とを有する横方向に長手の断面コ字状のカバーを設けたものを創作した。 The inventor of the present application uses the partition plate technology, and in a combustion apparatus provided with an exhaust duct in which a laterally elongated inflow port is formed in the rear surface portion and an outflow port is provided in the laterally central portion of the front surface portion. A front plate portion located in front of the inlet in the exhaust duct, and upper and lower plate portions extending rearward from both upper and lower edges of the front plate portion to reach an upper portion and a lower portion of the inlet portion of the rear surface portion of the exhaust duct. And a cover provided with a cover having a U-shaped cross section in the transverse direction.

このものでは、カバーで覆われる流入口の部分から流入する燃焼排ガスがカバー内で横方向一方と他方とに分流して、カバーの横方向両端部から横方向中央部の流出口に向けて流れることになり、上記（１）式のＬが大きくなって、共鳴周波数が小さくなる。然し、これでは、排気抵抗を十分に減少できないことが判明した。 In this case, the combustion exhaust gas flowing in from the inlet portion covered by the cover is divided into one side and the other side in the cover, and flows from the both lateral ends of the cover toward the outlet in the lateral center. As a result, L in the above equation (1) increases and the resonance frequency decreases. However, it has been found that this cannot sufficiently reduce the exhaust resistance.

特開２０１２−１１２６３５号公報JP 2012-112635 A

本発明は、以上の点に鑑み、後面部に横方向に細長い形状の流入口が形成され、前面部の横方向中央部に流出口が設けられた排気ダクトを備える燃焼装置であって、排気抵抗を減少して、且つ、共鳴騒音を十分に低減できるようにしたものを提供することをその課題としている。 In view of the above, the present invention is a combustion apparatus including an exhaust duct in which a laterally elongated inflow port is formed in a rear surface portion, and an outflow port is provided in a laterally central portion of a front surface portion. It is an object of the present invention to provide a device that can reduce resistance and sufficiently reduce resonance noise.

上記課題を解決するために、本発明は、バーナを内蔵する燃焼筐と、燃焼筐内に燃焼用空気を供給するファンと、燃焼筐の前面上部に接続された横方向に長手の箱形の排気ダクトとを備え、排気ダクトの後面部に、バーナの燃焼排ガスが流入する横方向に細長い形状の流入口が形成され、排気ダクトの前面部の横方向中央部に設けられた流出口から燃焼排ガスが前方に排出されるようにした燃焼装置において、排気ダクト内に、流入口の前方に位置する前板部と、前板部の上下両縁から後方にのびて排気ダクトの後面部の流入口の上方部分及び下方部分に達する上下の板部とを有する横方向に長手の断面コ字状のカバーが設けられ、カバーの上下の板部に、多数の透孔が形成されることを特徴とする。 In order to solve the above-mentioned problems, the present invention has a combustion casing with a built-in burner, a fan for supplying combustion air into the combustion casing, and a horizontally long box connected to the upper front of the combustion casing. An exhaust duct is provided, and a laterally elongated inflow port through which the combustion exhaust gas of the burner flows is formed at the rear surface portion of the exhaust duct, and combustion is performed from an outlet provided in the lateral center of the front portion of the exhaust duct. In a combustion apparatus in which exhaust gas is discharged forward, the front plate portion positioned in front of the inlet and the flow of the rear surface portion of the exhaust duct extending rearward from the upper and lower edges of the front plate portion in the exhaust duct. A transversely U-shaped cross-sectional cover having upper and lower plate portions reaching an upper portion and a lower portion of the inlet is provided, and a large number of through holes are formed in the upper and lower plate portions of the cover. And

本発明によれば、上記の如く、カバーで覆われる流入口の部分から流入する燃焼排ガスがカバー内で横方向一方と他方とに分流して、カバーの横方向両端部から横方向中央部の流出口に向けて流れることになり、上記（１）式のＬが大きくなって、共鳴周波数が小さくなり、共鳴騒音を低減できる。また、カバー内から上下の板部に形成した多数の透孔を介して燃焼排ガスが流れるため、排気抵抗が減少する。更に、カバーの横方向両端部からの燃焼排ガスの左右方向の流れと、カバーの上下の板部の透孔からの燃焼排ガスの上下方向の流れとが流出口の手前で合流するため、排気経路の異なる４つの音波が合わさることになり、共鳴騒音を一層効果的に低減できる。 According to the present invention, as described above, the flue gas flowing in from the portion of the inlet covered with the cover is divided into one side and the other side in the cover, and from the lateral end portions of the cover to the lateral center portion. It flows toward the outlet, L in the above equation (1) increases, the resonance frequency decreases, and resonance noise can be reduced. Further, since the exhaust gas flows from the inside of the cover through a large number of through holes formed in the upper and lower plate portions, the exhaust resistance is reduced. Further, since the flow in the left-right direction of the combustion exhaust gas from both lateral ends of the cover and the flow in the vertical direction of the combustion exhaust gas from the through holes in the upper and lower plate portions of the cover merge before the outlet, the exhaust path The four sound waves having different values are combined, and the resonance noise can be more effectively reduced.

また、本発明においては、カバーの前板部にも多数の透孔が形成されることが望ましい。これによれば、排気抵抗を更に減少できると共に、燃焼ガスの上述した左右方向及び上下方向の流れに加えて前板部の透孔から燃焼ガスの流れが流出口の手前で合流して、排気経路の異なる５つの音波が合わさることになり、共鳴騒音の低減効果が更に向上する。 In the present invention, it is desirable that a large number of through holes are also formed in the front plate portion of the cover. According to this, the exhaust resistance can be further reduced, and in addition to the above-described horizontal and vertical flows of the combustion gas, the flow of the combustion gas is merged from the through hole of the front plate portion before the outlet, and the exhaust gas is exhausted. Five sound waves having different paths are combined, and the effect of reducing resonance noise is further improved.

また、カバーの横方向中心位置は、前記流入口の横方向中心位置から横方向一方にずれていることが望ましい。これによれば、カバーの横方向一端を経由して流出口に達する排気経路の長さとカバーの横方向他端を経由して流出口に達する排気経路の長さとが異なることになり、両排気経路からの周波数の異なる２つの音波が干渉し合って、共鳴しにくくなる。 Further, it is desirable that the lateral center position of the cover is shifted in one lateral direction from the lateral center position of the inlet. According to this, the length of the exhaust path reaching the outflow port via one end in the horizontal direction of the cover is different from the length of the exhaust path reaching the outflow port via the other horizontal end of the cover. Two sound waves having different frequencies from the path interfere with each other and hardly resonate.

本発明の実施形態の燃焼装置を示す正面図。The front view which shows the combustion apparatus of embodiment of this invention. 図１のＩＩ−ＩＩ線で切断した拡大断面図。The expanded sectional view cut | disconnected by the II-II line | wire of FIG. 実施形態の燃焼装置に設けられた排気ダクトの分解状態の斜視図。The perspective view of the decomposition | disassembly state of the exhaust duct provided in the combustion apparatus of embodiment. 図３の排気ダクトの組立状態の切断平面図。FIG. 4 is a cut plan view of the exhaust duct of FIG. 3 in an assembled state.

図１、図２を参照して、１は、本発明の実施形態の燃焼装置である給湯用熱源機の外装ハウジングを示している。外装ハウジング１は、前面を開放したハウジング本体１１と、ハウジング本体１１の前面を覆う前パネル１２とで構成されている。 1 and 2, reference numeral 1 denotes an outer housing of a hot water supply heat source machine that is a combustion apparatus according to an embodiment of the present invention. The exterior housing 1 includes a housing body 11 having a front surface opened and a front panel 12 that covers the front surface of the housing body 11.

外装ハウジング１内には、図２に示す如く、燃焼筐２が設けられている。燃焼筐２内の下部にはバーナ３が配置され、中間部には、吸熱フィン４１に通水パイプ４２を挿通した顕熱回収型の主熱交換器４が配置され、上部には、吸熱パイプ５１群で構成される潜熱回収型の副熱交換器５が配置されている。また、燃焼筐２内のバーナ３より下方の部分には、バーナ配置部に対し分布板６１で仕切られた給気室６が設けられている。給気室６にはファン７が接続されており、このファン７によって給気室６に空気が供給される。給気室６には、バーナ３の混合管部３１に臨むガスノズル３２が配置されている。そして、給気室６内の空気の一部が混合管部３１に燃焼用一次空気として供給されると共に、分布板６１に形成した多数の分布孔（図示せず）を介してバーナ配置部に燃焼用二次空気として供給されるようにしている。 A combustion housing 2 is provided in the outer housing 1 as shown in FIG. A burner 3 is disposed in the lower part of the combustion housing 2, a sensible heat recovery type main heat exchanger 4 in which a water passage pipe 42 is inserted into a heat absorption fin 41 is disposed in the middle part, and a heat absorption pipe is disposed in the upper part. A latent heat recovery type sub heat exchanger 5 composed of 51 groups is arranged. Further, an air supply chamber 6 partitioned by a distribution plate 61 with respect to the burner arrangement portion is provided in a portion below the burner 3 in the combustion housing 2. A fan 7 is connected to the air supply chamber 6, and air is supplied to the air supply chamber 6 by the fan 7. A gas nozzle 32 facing the mixing pipe portion 31 of the burner 3 is disposed in the air supply chamber 6. A part of the air in the air supply chamber 6 is supplied to the mixing pipe portion 31 as primary air for combustion, and is also supplied to the burner arrangement portion through a number of distribution holes (not shown) formed in the distribution plate 61. It is supplied as secondary air for combustion.

燃焼筐２の上部前面には、副熱交換器５を通過したバーナ３の燃焼排ガスが流入する横方向に長手の箱形の排気ダクト８が接続されている。図３、図４も参照して、排気ダクト８は、後面が開放されたダクト本体８ａと、ダクト本体８ａの後面を閉塞する、燃焼筐２の上部前面に固定されるベース板８ｂとで構成されている。排気ダクト８の後面部たるベース板８ｂには、燃焼排ガスが流入する横方向に細長い形状の流入口８１が形成され、外装ハウジング１の前パネル１２に形成した開口を通して前方に露出する排気ダクト８の前面部たるダクト本体８ａの前面の横方向中央部には、燃焼排ガスを前方に排出する筒状の流出口８２が設けられている。 Connected to the upper front surface of the combustion housing 2 is a box-shaped exhaust duct 8 that is long in the lateral direction and into which the combustion exhaust gas of the burner 3 that has passed through the auxiliary heat exchanger 5 flows. 3 and 4, the exhaust duct 8 includes a duct main body 8a whose rear surface is opened and a base plate 8b which is fixed to the upper front surface of the combustion housing 2 and closes the rear surface of the duct main body 8a. Has been. The base plate 8b, which is the rear surface portion of the exhaust duct 8, is formed with a laterally long inflow port 81 through which combustion exhaust gas flows, and is exposed forward through an opening formed in the front panel 12 of the exterior housing 1. A cylindrical outlet 82 for discharging the combustion exhaust gas forward is provided at the center in the lateral direction of the front surface of the duct main body 8a, which is the front surface portion.

また、排気ダクト８内には、流入口８１の前方に位置する前板部８３ａと、前板部８３ａの上縁から後方にのびてベース板８ｂの流入口８１の上方部分に達する上板部８３ｂと、前板部８３ａの下縁から後方にのびてベース板８ｂの流入口８１の下方部分に達する下板部８３ｃとを有する横方向に長手の断面コ字状のカバー８３が設けられている。カバー８３の上下の板部８３ｂ、８３ｃと前板部８３ａには多数の透孔８３ｄが形成されている。 Further, in the exhaust duct 8, a front plate portion 83a positioned in front of the inflow port 81, and an upper plate portion extending rearward from the upper edge of the front plate portion 83a and reaching the upper portion of the inflow port 81 of the base plate 8b. A cover 83 having a U-shaped cross section extending in the lateral direction is provided, including 83b and a lower plate portion 83c extending rearward from the lower edge of the front plate portion 83a and reaching a lower portion of the inlet 81 of the base plate 8b. Yes. A number of through holes 83d are formed in the upper and lower plate portions 83b and 83c and the front plate portion 83a of the cover 83.

以上の構成によれば、カバー８３で覆われる流入口８１の部分から流入する燃焼排ガスがカバー８３内で横方向一方と他方とに分流して、カバー８３の横方向両端部から横方向中央部の流出口８２に向けて流れることになる。そのため、上記（１）式のＬが大きくなって、共鳴周波数が小さくなる。 According to the above configuration, the combustion exhaust gas flowing in from the portion of the inflow port 81 covered with the cover 83 is divided into one side and the other side in the cover 83, and from the lateral end portions of the cover 83 to the lateral center portion. It will flow toward the outflow port 82. Therefore, L in the above equation (1) increases and the resonance frequency decreases.

また、カバー８３内から上下の板部８３ｂ、８３ｃ及び前板部８３ａに形成した多数の透孔８３ｄを介して燃焼排ガスが流れるため、排気抵抗が減少する。更に、カバー８３の横方向両端部からの燃焼排ガスの左右方向の流れと、カバー８３の上下の板部８３ｂ、８３ｃの透孔８３ｄからの燃焼排ガスの上下方向の流れと、カバー８３の前板部８３ａからの燃焼排ガスの流れとが流出口の手前で合流するため、排気経路の異なる５つの音波が合わさることになり、共鳴騒音を一層効果的に低減できる。 Further, the exhaust gas flows from the cover 83 through a large number of through holes 83d formed in the upper and lower plate portions 83b and 83c and the front plate portion 83a, so that the exhaust resistance is reduced. Further, the flow of combustion exhaust gas from both lateral ends of the cover 83 in the left-right direction, the flow of combustion exhaust gas from the upper and lower plate portions 83b and 83c of the cover 83 in the vertical direction, and the front plate of the cover 83 Since the flow of the combustion exhaust gas from the portion 83a merges in front of the outlet, five sound waves with different exhaust paths are combined, and resonance noise can be further effectively reduced.

尚、透孔８３ｄは、共鳴音の周波数である低周波を通しにくい直径１〜４ｍｍ程度の比較的小径のものにすることが望ましい。これによれば、音響的な効果を損なうことなく、排気抵抗を減少させることができる。 It is desirable that the through hole 83d has a relatively small diameter of about 1 to 4 mm, which is difficult to pass a low frequency that is a frequency of resonance sound. According to this, exhaust resistance can be reduced without impairing the acoustic effect.

また、本実施形態では、図４に明示する如く、カバー８３の横方向中心位置Ｏは、流入口８１の横方向中心位置Ｏ´から横方向一方（図４の左方）にずれている。これによれば、カバー８３の横方向一端を経由して流出口８２に達する排気経路の長さとカバー８３の横方向他端を経由して流出口８２に達する排気経路の長さとが異なることになり、両排気経路からの周波数の異なる２つの音波が干渉し合って、より一層共鳴しにくくなる。 Further, in the present embodiment, as clearly shown in FIG. 4, the lateral center position O of the cover 83 is shifted from the lateral center position O ′ of the inflow port 81 in one lateral direction (left side in FIG. 4). According to this, the length of the exhaust path reaching the outlet 82 via one end in the lateral direction of the cover 83 is different from the length of the exhaust path reaching the outlet 82 via the other lateral end of the cover 83. Thus, two sound waves having different frequencies from the two exhaust paths interfere with each other and become more difficult to resonate.

以上、本発明の実施形態について図面を参照して説明したが、本発明はこれに限定されない。例えば、上記実施形態では、カバー８３の前板部８３ａにも透孔８３ｄを形成しているが、前板部８３ａの透孔を省略しても、上記段落００１２で記述したように排気抵抗を減少させて、且つ、共鳴騒音を低減するという効果が得られる。また、上記実施形態は、顕熱回収型の主熱交換器４と潜熱回収型の副熱熱交換器５とを有する熱源機に本発明を適用したものであるが、副熱交換器５は省略してもよく、また、熱源機以外の他の燃焼装置にも同様に本発明を適用できる。 As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to this. For example, in the above embodiment, the through hole 83d is also formed in the front plate portion 83a of the cover 83, but even if the through hole of the front plate portion 83a is omitted, the exhaust resistance is reduced as described in the paragraph 0012 above. The effect of reducing the resonance noise can be obtained. In the above embodiment, the present invention is applied to a heat source apparatus having a sensible heat recovery type main heat exchanger 4 and a latent heat recovery type sub heat heat exchanger 5. It may be omitted, and the present invention can be similarly applied to other combustion apparatuses other than the heat source machine.

２…燃焼筐、３…バーナ、７…ファン、８…排気ダクト、８１…流入口、８２…流出口、８３…カバー、８３ａ…前板部、８３ｂ…上板部、８３ｃ…下板部、８３ｄ…透孔。 2 ... Combustion housing, 3 ... Burner, 7 ... Fan, 8 ... Exhaust duct, 81 ... Inlet, 82 ... Outlet, 83 ... Cover, 83a ... Front plate part, 83b ... Upper plate part, 83c ... Lower plate part, 83d ... through hole.

Claims

バーナを内蔵する燃焼筐と、燃焼筐内に燃焼用空気を供給するファンと、燃焼筐の上部前面に接続された横方向に長手の箱形の排気ダクトとを備え、排気ダクトの後面部に、バーナの燃焼排ガスが流入する横方向に細長い形状の流入口が形成され、排気ダクトの前面部の横方向中央部に設けられた流出口から燃焼排ガスが前方に排出されるようにした燃焼装置において、
排気ダクト内に、流入口の前方に位置する前板部と、前板部の上下両縁から後方にのびて排気ダクトの後面部の流入口の上方部分及び下方部分に達する上下の板部とを有する横方向に長手の断面コ字状のカバーが設けられ、カバーの上下の板部に、多数の透孔が形成されることを特徴とする燃焼装置。 Composed of a combustion housing with a burner, a fan for supplying combustion air into the combustion housing, and a box exhaust duct that is horizontally long and connected to the upper front surface of the combustion housing. Combustion apparatus in which an inflow port having a horizontally long shape into which combustion exhaust gas from a burner flows is formed, and combustion exhaust gas is discharged forward from an outlet provided in the center in the lateral direction of the front portion of the exhaust duct In
A front plate portion located in front of the inflow duct in the exhaust duct, and upper and lower plate portions extending rearward from both upper and lower edges of the front plate portion and reaching an upper portion and a lower portion of the rear portion of the exhaust duct. A combustion apparatus, wherein a cover having a U-shaped cross section in the transverse direction is provided in the lateral direction, and a large number of through holes are formed in upper and lower plate portions of the cover.

前記カバーの前板部にも多数の透孔が形成されることを特徴とする請求項１記載の燃焼装置。 The combustion apparatus according to claim 1, wherein a number of through holes are also formed in a front plate portion of the cover.

前記カバーの横方向中心位置は、前記流入口の横方向中心位置から横方向一方にずれていることを特徴とする請求項１又は２記載の燃焼装置。 The combustion apparatus according to claim 1 or 2, wherein a lateral center position of the cover is shifted in one lateral direction from a lateral center position of the inflow port.