JP3708145B2

JP3708145B2 - Burner equipment

Info

Publication number: JP3708145B2
Application number: JP24272894A
Authority: JP
Inventors: 豊白井; 正一原; 直樹石倉; 好文守屋
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 1994-10-06
Filing date: 1994-10-06
Publication date: 2005-10-19
Anticipated expiration: 2020-10-19
Also published as: JPH08110013A

Description

【０００１】
【産業上の利用分野】
本発明は、家庭用燃焼機器に適した低ＮＯｘ化燃焼技術に関するものである。
【０００２】
【従来の技術】
従来、この種の装置は、図４の特公昭６２−３９３２９号公報のように、ブンゼンバーナ１１の上面に部分的に開口する一次炎孔１２を有し、二次炎孔１４を設けた一次燃焼室壁１３にて覆った構成であった。この構成により最大燃焼時の火炎は、一次炎孔１２上に一次炎１５が、二次炎孔１４上に二次炎１６が形成される。また，最小燃焼時は一次炎孔１２上の一次炎１５の直ぐ外側で、二次炎孔１４での二次炎１６の形成ができなくて、一次燃焼室壁内の一次炎１５の直ぐ外側に二次炎１６ａが形成されていた。
【０００３】
【発明が解決しようとする課題】
しかしながら、この種の二段燃焼において通常一次炎孔１２および二次炎孔１４の負荷は最大燃焼量に適した値で設計する。このため最大燃焼では各炎孔１２，１４での保炎による完全な２段燃焼が形成できる。一方、燃焼量を絞ると二次炎孔１４上の負荷が低くなりすぎるために、二次炎１６が二次炎孔１４上で形成されにくく２段燃焼にならず、一次炎孔１２上で一次炎１５の外に二次炎１６ａが一体的にできる通常の予混合火炎となり燃焼排気ガス中のＮＯｘ濃度は増加する。即ち燃焼量が減ると二段燃焼が行われず、低ＮＯｘ燃焼が実現できなくなるという課題があった。また雰囲気中の酸素濃度が低下した条件では一次炎がリフトしやすくなるという課題があった。
【０００４】
【課題を解決するための手段】
上記課題を解決するために、本発明のバーナー装置によれば、一次炎孔を持つブンゼンバーナを備え、このブンゼンバーナを収納してブンゼンバーナの一次炎孔より上部の空間を燃焼室とし、燃焼室上部を開口して高燃焼時用の二次炎孔を備え、前記燃焼室内に前記ブンゼンバーナの一次炎孔を覆うと共に一次火炎の熱をバーナ本体に熱伝導するための補助燃焼室固定部を設けた補助燃焼室を、補助燃焼室上部には、開口した弱時燃焼用の補助燃焼室炎孔を、さらに二次炎孔上部には補炎体を備えたものである。
【０００５】
燃焼室内火炎に対して、燃焼室壁に外気と連通した空気孔を設け、かつ補助燃焼室側壁にも燃焼室内空気と連通した補助空気孔を備えたものである。
【０００６】
補助燃焼室炎孔の炎孔形状及び、二次炎孔の炎孔形状は、燃焼火炎の分布形状に対応した開口形状を設定し、かつ補助燃焼室炎孔負荷は一次炎孔負荷より小さく、かつ二次炎孔負荷と同等もしくは大きくなるようにしたものである。
【０００７】
【作用】
上記構成によって次の作用となる。
【０００８】
燃焼量が多いときは二次炎は二次炎孔上に形成され二段燃焼となる。また、燃焼量が少ない時は二次炎は補助燃焼室炎孔上に形成され、二次炎の位置は変わってもやはり二段燃焼となる。そして、補炎体へ火炎が接触することにより還元炎となる。また補助燃焼室内の一次炎は補助燃焼室壁からの熱反射で一次炎温度を上げ安定した二段燃焼が実現でき、全燃焼範囲において良好な低ＮＯｘ燃焼が可能となる。また、補助燃焼室の下部に設けた一次火炎の熱をバーナ本体に熱伝導するための補助燃焼室固定部を一次炎孔近傍のバーナ本体に密着して固定することにより、バーナ本体が加熱され、バーナ本体内の燃料ガスが膨張して一次炎孔よりのガスの噴出スピードは上昇するため、一次空気面積は、前記一次炎孔よりのガスの噴出スピード上昇により吸い込み度合いが増すため、一次空気面積の低減が図れ、高燃焼時の空気過剰を抑えて燃焼性能をより向上できる。
【０００９】
低酸素濃度状態及び一次空気量の不足時状態では一次炎が燃焼量に依らずリフトしやすいため、燃焼室壁に外気と連通する空気孔を設けることにより、低酸素濃度状態及び一次空気量の不足時は空気孔より燃焼用空気を取り入れて一次炎の安定化が図れる。また補助燃焼室壁に燃焼室内と連通する補助空気孔を設けることにより、低酸素濃度状態及び一次空気量の不足時は、補助空気孔より燃焼室内の燃焼用空気を取り入れて一次炎の安定化が図れる。
【００１０】
弱燃焼時の一次炎分布に対応した補助燃焼室炎孔形状とし、かつ補助燃焼室炎孔負荷は一次炎孔負荷より小さくすることにより、一次炎孔より噴出されるガスの噴出速度が抑えられて一次炎孔上に一次炎が形成し、補助燃焼室炎孔上に二次炎の二段燃焼形成ができて補炎効果を高める。また、高燃焼時の一次炎分布に対応した二次炎孔形状とし、かつ二次炎孔負荷は補助燃焼室炎孔負荷と同等または小さくすることにより、一次炎孔上で一次炎が形成されて二次炎孔上で二次炎が形成され二段燃焼が形成される。前記炎孔形状と炎孔負荷を設定することにより、燃焼量に応じて二段燃焼が形成され、良好な低ＮＯｘ燃焼が可能となる。
【００１１】
【実施例】
以下、本発明の実施例を図面に基づいて説明する。図１は温風暖房器の断面図である。図において、１はバーナ本体であり、２の一次炎孔を有する。一次炎孔２はバーナ１の上面もしくは側面にもあり一次炎孔形状はスリットを長くしたもの、あるいは、丸孔とする構成でもよい。また一次炎孔２の開口を金網にて覆う構成としてもよい。３は補助燃焼室であり、バーナ１の上部を収納する。燃焼室４は燃焼ガイドＡ６と燃焼ガイドＢ７と燃焼ガイドＣ８にて覆われており燃焼室４の上部には補炎体のコイル３２が取り付けられている。燃焼時はモーターの駆動にて羽根１０が回転し、羽根ガイド１７に沿ってバーナ１にて加熱された温風が流れる。バーナ１にて加熱された熱気は羽根１０により吸引される。
【００１２】
バーナ１の燃焼に必要な空気は、燃焼ガイドＢ７と燃焼ガイドＣ８の右側の隙間を通過して燃焼用空気となる。また、燃焼ガイドＣ８と燃焼ガイドＡ６の間を通過した空気は、バーナ１にて加熱された熱気と混合され温風となり、羽根１０の吸引力にて羽根ガイド１７に沿って流れる。燃焼ガイドＤ１８はバーナ１にて加熱された熱気の通路のガイドである。燃焼室ユニット２４は外装箱２５で覆われており、羽根ガイド１７に沿って流れてきた温風は外装箱２５に備えられた温風吹き出し口２６より吹き出される。次に燃焼室４と、補助燃焼室３とバーナ１の構成について、図２，図３を基に説明する。図において、補助燃焼室３は上面に補助燃焼室炎孔５を備えておりバーナ１の一次炎孔２の近傍部２９（破線で囲った箇所）を覆うように構成されている。補助燃焼室３の下部の補助燃焼室固定部２８はバーナ１の一次炎孔２の近傍部２９に一次炎孔２を覆わないように密着固定されている。固定補助燃焼室３は一次炎１９の輻射熱によって加熱されているため補助燃焼室固定部２８も熱伝導にて加熱昇温されている。一次炎孔２の近傍部２９も一次炎１９で直接加熱されており、補助燃焼室固定部２８の熱伝導を加えて近傍部２９の加熱はバーナ１全体に伝熱され、バーナ１全体の温度が上昇することにより、バーナ１内の燃料ガスが加熱膨脹する。
【００１３】
バーナ１内の燃料ガスが膨脹して比重が軽くなると、外部の空気との比重差が増えて一次炎孔２からのガスの噴出スピードが上昇する。ガスの噴出スピードの上昇によりバーナ入口３０からの一次空気の吸い込み量が増加する。つまり、一次炎孔２から燃料ガスを噴出させる力としてのドラフトが大きくなり補助燃焼室３を取付けないときよりもバーナ入口３０からの一次空気の吸引量が増加する。一次炎１９は全燃焼範囲において形成されるので、このドラフトの増大は全ての燃焼状態で期待できる。従って、バーナ入口３０でのダンパー等による吸入空気量の調節は締め加減が必要となる。
【００１４】
ところで、従来から低燃焼時はどうしても空気吸入量の率が高燃焼時に比べて増加するため、高燃焼時での空気過剰率を少し減らす設計配慮によって、低燃焼時の空気過剰気味な状態を十分とは言えないまでもカバーしていた。しかし、この補助燃焼室３を取り付ければ上記したドラフトの増大が期待でき、高燃焼時における低燃焼性能良化のための余分な、燃焼性能を敢えて低下させねばならない過剰空気率を減らし、より良好な高燃焼性能が得られる。更に、補助燃焼室３の付加は、中間燃焼性能も改善できる。つまり、補助燃焼室３は前記高燃焼時の間にある全ての中間的な燃焼時において、一次炎１９の放射熱が補助燃焼室３を加熱して蓄熱する。そして蓄熱した補助燃焼室３は補助燃焼室固定部２８を介してバーナ１を加熱すると共に、一部の放射熱を反射して一次炎１９を昇温する。つまり、一次炎１９は火炎温度が上昇して火炎形成性能としての補炎性能が強くなり、一次炎１９の燃焼性能が向上して二次炎１２完結後の燃焼性能を高めることができる。
【００１５】
次に、補助燃焼室炎孔５の形状はバーナ１の弱燃焼時の火炎分布に対応しており弱燃焼時火炎はバーナ先端部の火炎が大きくバーナ根元側火炎が小さいため火炎分布に対応して補助燃焼室炎孔先端部３４ａを広く補助燃焼室炎孔根元部３４ｂを狭くしている。但しバーナ火炎分布の形状により補助炎孔先端部寸法及び補助炎孔根元部寸法は設定される。
【００１６】
さらに二次炎孔２０の形状もバーナ１の高燃焼時の火炎分布に対応しており高燃焼時火炎はバーナ先端部の火炎が大きくバーナ根元側の火炎が小さいため火炎分布に対応して二次炎孔先端部３５ａを広く二次炎孔根元部３５ｂを狭くしている。但しバーナ火炎分布の形状により二次炎孔先端部寸法及び形状、二次炎孔根元部寸法及び形状は設定される。
【００１７】
また、バーナ１の炎孔長手方向寸法１２に対して補助燃焼室炎孔５の開口長手方向寸法１３の方が長く、かつ二次炎孔２０の開口長手方向寸法１４の方がより長く設定されている。
【００１８】
さらに補助燃焼室炎孔負荷（補助燃焼室３での燃焼量の炎孔面積２２比）は一次炎孔２の一次炎孔負荷より小さくなっており、二次炎孔２０の二次炎孔負荷（二次炎孔２２で燃焼する燃焼量の炎孔面積２３比）は前記補助炎孔負荷２２と同等もしくは大きく形成されている。燃焼室４内に設けられた補助燃焼室３の高さ位置Ｌ１についてはバーナ１の最大燃焼量と最小燃焼量による燃焼範囲に応じて設定される。
【００１９】
上記のように構成されたバーナ装置での燃焼量が多い場合は、一次炎孔２上に一次炎１９を、そして二次炎孔２０上に二次炎１２を形成し、完全な二段分離火炎となる。また燃焼量が少ないときは、一次炎１９は一次炎孔２上に、そして二次炎１２ａは補助燃焼室炎孔５上に形成され、ここでも完全な二段分離火炎となる。このため燃焼量の全域で完全な二段分離火炎が実現でき、かつ燃焼室の上部に補炎体のコイル３２を設置することにより二次炎がコイルに接触し還元作用により安定した低ＮＯｘ燃焼が実現できる。コイル３２の長手方向寸法１５は、二次炎孔２０の長手方向寸法１４より長く設定されている。
【００２０】
一方、一次空気不足あるいは雰囲気中の酸素濃度が低下した条件下では、一次炎１９がリフトしやすくなる。実際、外装箱２５の後方に備えたフィルター付き空気吸入口が長時間の使用によってホコリ詰まりしてくると、ファン１０による吸入空気量が低下してバーナ入口３０からバーナ１へ吸入できる燃焼用の一次空気量も減ってくる。このようにして一次空気不足が発生すると、燃焼用の酸素不足で二次炎孔２０に到達した未然の混合気体は、燃焼用空気を求めて二次炎孔２０から周囲に散らばって早く燃焼を完結しようとする。この現象は燃焼に十分な酸素供給できる、いわゆる補炎作用と全く逆作用と言えて、従ってリフト現象が発生する。
【００２１】
また、密閉した室内での長時間燃焼によって、新鮮な空気との攪散による、酸素供給のない使用例では、どうしても空気中の酸素含有率は低下して、つまり酸素濃度が下がることになる。このときも、上述の一次空気不足と類似して燃焼はリフト気味になって行き、ＣＯガスやＮＯｘ等の有害ガスの発生率が増える。このような場合は、燃焼室４の空気孔２７が、外気と連通しており、かつ、補助燃焼室の補助空気孔３３が燃焼室内燃焼空気と連通しているため、一次炎１９の燃焼が不安定化しようとしても燃焼用空気の流入が図れる。
【００２２】
空気孔２７及び補助空気孔３３は正常時には二次炎１２に対する若干の一次空気の供給と、二次炎１２ａに対しては若干の二次空気供給の作用を持っている。そして上述のような酸素供給量が不足する場合では、緊急空気供給孔として作用してある限度の低酸素濃度になるまで、燃焼性能の悪化度合いを緩和できる。つまり正常時には全くその作用を期待する必要がない程度に作用するが、低酸素濃度のときに作用が期待できるような開口面積で済ますことができ、また正常時の作用をもっと積極的に持たせても良い。
【００２３】
【発明の効果】
以上のように本発明のバーナ装置によれば、次の効果が得られる。
【００２４】
（１）請求項１では、バーナ本体を二次炎孔を有する箱体で覆い、さらにバーナ本体の一次炎孔を補助炎孔を有する補助燃焼室にて伝熱可能に覆うことにより、補助燃焼室の補助燃焼室炎孔が一次炎孔上の一次炎の保炎性を高めるため、排気ガス中のＣＯも低くでき全燃焼範囲に及んで安定した二段燃焼が実現できる。また補助燃焼室からの伝熱等によってバーナ本体の温度が上昇するためバーナ本体内のガスの温度が上昇しガスの噴出速度が早まるため、一次空気面積の減少も図れ、高燃焼側での過剰空気率を抑えてかつ補炎体のコイルを取り付けることにより二次炎がコイルに接触し還元作用にて低ＮＯｘ燃焼が可能となる。
【００２５】
（２）請求項２では、外気と連通している燃焼室壁に空気孔を設けさらに補助燃焼室側壁に補助空気孔を設けることにより、一次空気不足時及び、雰囲気中の酸素濃度低下等に対して燃焼用の補助空気の流入が図れ、火炎を安定化することができ燃焼検知用センサーの取り付け容易化も図れる。
【００２６】
（３）請求項３では、燃焼量が少ない時は、補助燃焼室炎孔が一次炎孔上の一次炎の補炎性を高め、燃焼量が多い時は二次炎孔が一次炎孔上の一次炎の補炎性を高めるため、排気ガス中のＣＯも低減できる。
【図面の簡単な説明】
【図１】本発明の一実施例におけるバーナ装置の縦断面図
【図２】（イ）同バーナ装置のバーナの外観側面図
（ロ）同バーナのＡ−Ａ線断面図
（ハ）同バーナの上面図
【図３】同バーナ装置の燃焼室の燃焼状態を示す縦断面図
【図４】従来のバーナ装置の燃焼室の縦断面図
【符号の説明】
１バーナ本体
２一次炎孔
３補助燃焼室
４燃焼室
５補助燃焼室炎孔
１２二次炎
１９一次炎
２０二次炎孔
２７燃焼室空気孔
３２補炎体
３３補助空気孔[0001]
[Industrial application fields]
The present invention relates to a low NOx combustion technology suitable for household combustion equipment.
[0002]
[Prior art]
Conventionally, this type of apparatus has a primary flame hole 12 partially opened on the upper surface of the Bunsen burner 11 and a secondary flame hole 14 as shown in Japanese Patent Publication No. 62-39329 in FIG. The configuration was covered with the combustion chamber wall 13. With this configuration, the flame at the maximum combustion forms a primary flame 15 on the primary flame hole 12 and a secondary flame 16 on the secondary flame hole 14. Further, at the time of the minimum combustion, the secondary flame 16 cannot be formed in the secondary flame hole 14 just outside the primary flame 15 on the primary flame hole 12, and the primary flame 15 inside the primary combustion chamber wall is just outside. The secondary flame 16a was formed.
[0003]
[Problems to be solved by the invention]
However, in this type of two-stage combustion, the loads on the primary flame holes 12 and the secondary flame holes 14 are usually designed with values suitable for the maximum combustion amount. Therefore, in the maximum combustion, complete two-stage combustion can be formed by holding the flames in the flame holes 12 and 14. On the other hand, if the amount of combustion is reduced, the load on the secondary flame hole 14 becomes too low, so that the secondary flame 16 is not easily formed on the secondary flame hole 14 and does not become two-stage combustion, but on the primary flame hole 12. A normal premixed flame in which the secondary flame 16a is integrally formed outside the primary flame 15 becomes a NOx concentration in the combustion exhaust gas. That is, when the combustion amount is reduced, there is a problem that the two-stage combustion is not performed and the low NOx combustion cannot be realized. Further, there is a problem that the primary flame is easily lifted under a condition where the oxygen concentration in the atmosphere is lowered.
[0004]
[Means for Solving the Problems]
In order to solve the above problems, according to the burner apparatus of the present invention, it comprises a Bunsen burner having a primary burner ports, and the upper part of the space and the combustion chamber from the primary burner ports of Bunsen burner accommodates the Bunsen burner, combustion Auxiliary combustion chamber fixing part for opening the chamber upper part and providing a secondary flame hole for high combustion, covering the primary flame hole of the Bunsen burner in the combustion chamber and conducting heat of the primary flame to the burner body The auxiliary combustion chamber is provided with an open auxiliary combustion chamber flame hole for weak combustion at the upper portion of the auxiliary combustion chamber, and a flame retardant at the upper portion of the secondary flame hole.
[0005]
The combustion chamber flame is provided with an air hole communicating with the outside air on the combustion chamber wall, and an auxiliary air hole communicating with the combustion chamber air is also provided on the side wall of the auxiliary combustion chamber.
[0006]
The flame shape of the auxiliary combustion chamber flame hole and the flame hole shape of the secondary flame hole set an opening shape corresponding to the distribution shape of the combustion flame, and the auxiliary combustion chamber flame load is smaller than the primary flame hole load, And it is made equal to or larger than the secondary flame hole load.
[0007]
[Action]
With the above configuration, the following action is obtained.
[0008]
When the amount of combustion is large, the secondary flame is formed on the secondary flame hole and becomes two-stage combustion. When the amount of combustion is small, the secondary flame is formed on the auxiliary combustion chamber flame hole, and even if the position of the secondary flame changes, the secondary combustion is still performed. And it becomes a reducing flame when a flame contacts a flame retardant. In addition, the primary flame in the auxiliary combustion chamber can achieve stable two-stage combustion by raising the temperature of the primary flame by heat reflection from the wall of the auxiliary combustion chamber, and good low NOx combustion is possible in the entire combustion range. In addition, the burner body is heated by fixing the auxiliary combustion chamber fixing portion provided in the lower part of the auxiliary combustion chamber in close contact with the burner body in the vicinity of the primary flame hole for conducting heat of the primary flame to the burner body. Since the fuel gas in the burner body expands and the gas ejection speed from the primary flame hole increases, the primary air area increases the degree of suction by increasing the gas ejection speed from the primary flame hole. The area can be reduced, and the combustion performance can be further improved by suppressing excess air during high combustion.
[0009]
In the low oxygen concentration state and when the primary air amount is insufficient, the primary flame is likely to lift regardless of the combustion amount.Therefore, by providing an air hole communicating with the outside air on the combustion chamber wall, the low oxygen concentration state and the primary air amount are reduced. When there is a shortage, the combustion flame can be taken in through the air holes to stabilize the primary flame. In addition, by providing an auxiliary air hole communicating with the combustion chamber on the auxiliary combustion chamber wall, when the oxygen concentration is low and the amount of primary air is insufficient, the combustion air in the combustion chamber is introduced from the auxiliary air hole to stabilize the primary flame. Can be planned.
[0010]
By making the auxiliary combustion chamber flame hole shape corresponding to the primary flame distribution during weak combustion and making the auxiliary combustion chamber flame hole load smaller than the primary flame hole load, the gas injection speed from the primary flame hole can be suppressed. As a result, a primary flame is formed on the primary flame hole, and a secondary flame is formed on the auxiliary combustion chamber flame hole, thereby enhancing the supplementary flame effect. In addition, by forming a secondary flame shape corresponding to the primary flame distribution during high combustion and making the secondary flame hole load equal to or smaller than the auxiliary combustion chamber flame hole load, a primary flame is formed on the primary flame hole. As a result, a secondary flame is formed on the secondary flame hole and a two-stage combustion is formed. By setting the flame hole shape and the flame hole load, two-stage combustion is formed according to the combustion amount, and good low NOx combustion becomes possible.
[0011]
【Example】
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of a hot air heater. In the figure, 1 is a burner body, and has 2 primary flame holes. The primary flame hole 2 is also on the upper surface or side surface of the burner 1, and the primary flame hole shape may be a long slit or a round hole. The opening of the primary flame hole 2 may be covered with a wire mesh. Reference numeral 3 denotes an auxiliary combustion chamber that houses the upper portion of the burner 1. The combustion chamber 4 is covered with a combustion guide A6, a combustion guide B7, and a combustion guide C8. During combustion, the blades 10 are rotated by driving the motor, and warm air heated by the burner 1 flows along the blade guides 17. Hot air heated by the burner 1 is sucked by the blades 10.
[0012]
The air necessary for the combustion of the burner 1 passes through the gap on the right side of the combustion guide B7 and the combustion guide C8 and becomes combustion air. Further, the air that has passed between the combustion guide C8 and the combustion guide A6 is mixed with hot air heated by the burner 1 to become warm air, and flows along the blade guide 17 by the suction force of the blade 10. The combustion guide D18 is a guide for the passage of hot air heated by the burner 1. The combustion chamber unit 24 is covered with an outer box 25, and the hot air flowing along the blade guide 17 is blown out from a hot air outlet 26 provided in the outer box 25. Next, the structure of the combustion chamber 4, the auxiliary combustion chamber 3, and the burner 1 is demonstrated based on FIG. 2, FIG. In the drawing, the auxiliary combustion chamber 3 is provided with an auxiliary combustion chamber flame hole 5 on the upper surface, and is configured to cover a vicinity 29 (a portion surrounded by a broken line) of the primary flame hole 2 of the burner 1. The auxiliary combustion chamber fixing portion 28 at the lower portion of the auxiliary combustion chamber 3 is closely fixed to the vicinity 29 of the primary flame hole 2 of the burner 1 so as not to cover the primary flame hole 2. Since the fixed auxiliary combustion chamber 3 is heated by the radiant heat of the primary flame 19, the auxiliary combustion chamber fixing portion 28 is also heated and heated by heat conduction. The vicinity 29 of the primary flame hole 2 is also directly heated by the primary flame 19, the heat conduction of the auxiliary combustion chamber fixing part 28 is applied, and the heating of the vicinity 29 is transferred to the entire burner 1, so that the temperature of the entire burner 1 is increased. Rises, the fuel gas in the burner 1 is heated and expanded.
[0013]
When the fuel gas in the burner 1 expands and the specific gravity becomes lighter, the specific gravity difference from the outside air increases, and the gas ejection speed from the primary flame hole 2 increases. The amount of primary air sucked from the burner inlet 30 increases as the gas ejection speed increases. That is, the draft as a force for ejecting the fuel gas from the primary flame hole 2 is increased, and the amount of primary air sucked from the burner inlet 30 is increased as compared with the case where the auxiliary combustion chamber 3 is not attached. Since the primary flame 19 is formed in the entire combustion range, this increase in draft can be expected in all combustion states. Therefore, adjustment of the amount of intake air by a damper or the like at the burner inlet 30 needs to be adjusted.
[0014]
By the way, since the rate of air intake volume will inevitably increase compared to that during high combustion during low combustion, design considerations that slightly reduce the excess air ratio during high combustion will ensure that there is a sufficient excess of air during low combustion. I couldn't say that. However, if this auxiliary combustion chamber 3 is installed, the above-mentioned draft can be expected to increase, reducing the excess air ratio that has to deliberately lower the combustion performance at the time of high combustion, and improving the combustion performance. High combustion performance. Furthermore, the addition of the auxiliary combustion chamber 3 can also improve the intermediate combustion performance. That is, in the auxiliary combustion chamber 3, the radiant heat of the primary flame 19 heats and stores the auxiliary combustion chamber 3 during all intermediate combustion during the high combustion. The stored auxiliary combustion chamber 3 heats the burner 1 through the auxiliary combustion chamber fixing portion 28 and reflects a part of the radiant heat to raise the temperature of the primary flame 19. That is, the flame temperature of the primary flame 19 rises and the flame-compensating performance as the flame forming performance becomes stronger, the combustion performance of the primary flame 19 is improved, and the combustion performance after the completion of the secondary flame 12 can be enhanced.
[0015]
Next, the shape of the auxiliary combustion chamber flame hole 5 corresponds to the flame distribution at the time of weak combustion of the burner 1, and the flame at the time of weak combustion corresponds to the flame distribution because the flame at the tip of the burner is large and the flame at the root side of the burner is small. Thus, the auxiliary combustion chamber flame hole tip 34a is widened and the auxiliary combustion chamber flame hole root 34b is narrowed. However, the auxiliary flame hole tip size and the auxiliary flame hole root size are set according to the shape of the burner flame distribution.
[0016]
Further, the shape of the secondary flame hole 20 also corresponds to the flame distribution at the time of high combustion of the burner 1, and the flame at the time of high combustion corresponds to the flame distribution because the flame at the tip of the burner is large and the flame at the burner root side is small. The secondary flame hole tip 35a is widened and the secondary flame hole root 35b is narrowed. However, the secondary flame hole tip size and shape, and the secondary flame hole root size and shape are set according to the shape of the burner flame distribution.
[0017]
Further, the opening longitudinal dimension 13 of the auxiliary combustion chamber flame hole 5 is set longer than the flame hole longitudinal dimension 12 of the burner 1, and the opening longitudinal dimension 14 of the secondary flame hole 20 is set longer. ing.
[0018]
Further, the auxiliary combustion chamber flame load (combustion amount flame ratio 22 in the auxiliary combustion chamber 3) is smaller than the primary flame load of the primary flame hole 2, and the secondary flame hole load of the secondary flame hole 20 is smaller. The ratio of the combustion area burned in the secondary flame hole 22 is 23 or larger than the auxiliary flame hole load 22. The height position L1 of the auxiliary combustion chamber 3 provided in the combustion chamber 4 is set according to the combustion range of the burner 1 with the maximum combustion amount and the minimum combustion amount.
[0019]
When the amount of combustion in the burner device configured as described above is large, the primary flame 19 is formed on the primary flame hole 2 and the secondary flame 12 is formed on the secondary flame hole 20, and complete two-stage separation is performed. It becomes a flame. When the amount of combustion is small, the primary flame 19 is formed on the primary flame hole 2 and the secondary flame 12a is formed on the auxiliary combustion chamber flame hole 5, which again becomes a complete two-stage separated flame. For this reason, a complete two-stage separated flame can be realized over the entire combustion amount, and a low-flame NOx combustion in which the secondary flame comes into contact with the coil and is stabilized by the reduction action by installing the auxiliary flame coil 32 in the upper part of the combustion chamber. Can be realized. The longitudinal dimension 15 of the coil 32 is set longer than the longitudinal dimension 14 of the secondary flame hole 20.
[0020]
On the other hand, the primary flame 19 is likely to lift under conditions where the primary air is insufficient or the oxygen concentration in the atmosphere is reduced. In fact, if the air inlet with a filter provided behind the outer box 25 becomes clogged with dust over a long period of time, the amount of air taken in by the fan 10 decreases, and the combustion air can be sucked into the burner 1 from the burner inlet 30. The primary air volume will also decrease. When the primary air shortage occurs in this way, the gas mixture that has reached the secondary flame hole 20 due to the lack of oxygen for combustion is scattered around the secondary flame hole 20 in search of the combustion air and burned quickly. Try to complete. This phenomenon can be said to be completely opposite to the so-called inflaming action that can supply oxygen sufficient for combustion, and therefore a lift phenomenon occurs.
[0021]
In addition, due to long-term combustion in a sealed room, in an example of use without oxygen supply due to disturbance with fresh air, the oxygen content in the air inevitably decreases, that is, the oxygen concentration decreases. Also at this time, the combustion becomes lifted like the primary air shortage described above, and the generation rate of harmful gases such as CO gas and NOx increases. In such a case, since the air hole 27 of the combustion chamber 4 communicates with the outside air, and the auxiliary air hole 33 of the auxiliary combustion chamber communicates with the combustion air in the combustion chamber, the combustion of the primary flame 19 is prevented. Even when trying to destabilize, inflow of combustion air can be achieved.
[0022]
The air hole 27 and the auxiliary air hole 33 have a function of supplying a little primary air to the secondary flame 12 and a little secondary air supply to the secondary flame 12a in a normal state. When the oxygen supply amount is insufficient as described above, the degree of deterioration in combustion performance can be reduced until the oxygen concentration reaches a certain low oxygen concentration acting as an emergency air supply hole. In other words, it works to the extent that it is not necessary to expect its effect at normal times, but it can be done with an opening area that can be expected to work at low oxygen concentrations, and it will have a more active effect at normal times. May be.
[0023]
【The invention's effect】
As described above, according to the burner device of the present invention, the following effects can be obtained.
[0024]
(1) In claim 1, the burner body is covered with a box having a secondary flame hole, and the primary flame hole of the burner body is covered in an auxiliary combustion chamber having an auxiliary flame hole so that heat can be transferred, thereby performing auxiliary combustion. Since the auxiliary combustion chamber flame hole of the chamber enhances the flame holding property of the primary flame on the primary flame hole, CO in the exhaust gas can be lowered, and stable two-stage combustion can be realized over the entire combustion range. Also, because the temperature of the burner body rises due to heat transfer from the auxiliary combustion chamber, etc., the temperature of the gas in the burner body rises and the gas ejection speed increases, so the primary air area can be reduced and excessive on the high combustion side The secondary flame comes into contact with the coil by attaching the coil of the flame retardant while suppressing the air ratio, and low NOx combustion is possible by the reduction action.
[0025]
(2) In claim 2, by providing an air hole in the combustion chamber wall communicating with the outside air and further providing an auxiliary air hole in the side wall of the auxiliary combustion chamber, when the primary air is insufficient, the oxygen concentration in the atmosphere is reduced, etc. On the other hand, inflow of auxiliary air for combustion can be achieved, the flame can be stabilized, and the attachment of the sensor for detecting combustion can be facilitated.
[0026]
(3) In claim 3, when the combustion amount is small, the auxiliary combustion chamber flame hole enhances the flame resistance of the primary flame on the primary flame hole, and when the combustion amount is large, the secondary flame hole is on the primary flame hole. CO in exhaust gas can also be reduced in order to improve the flame resistance of the primary flame.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a burner device according to an embodiment of the present invention. FIG. 2A is a side view of the burner of the burner device. FIG. 1B is a sectional view taken along line AA of the burner. Fig. 3 is a longitudinal sectional view showing a combustion state of a combustion chamber of the burner device. Fig. 4 is a longitudinal sectional view of a combustion chamber of a conventional burner device.
DESCRIPTION OF SYMBOLS 1 Burner body 2 Primary flame hole 3 Auxiliary combustion chamber 4 Combustion chamber 5 Auxiliary combustion chamber flame hole 12 Secondary flame 19 Primary flame 20 Secondary flame hole 27 Combustion chamber air hole 32 Auxiliary body 33 Auxiliary air hole

Claims

A Bunsen burner having a primary flame hole, a combustion chamber in which the Bunsen burner is accommodated and provided in a space above the primary flame hole, and a secondary for high combustion provided by opening the upper part of the combustion chamber An auxiliary combustion chamber provided with a flame hole, an auxiliary combustion chamber fixing portion for covering the primary flame hole of the Bunsen burner provided in the combustion chamber and conducting heat of the primary flame to the burner body, and the auxiliary combustion chamber A burner device provided with an auxiliary combustion chamber flame hole opened at the top of the auxiliary combustion chamber for use in weak combustion, and a flame retardant at the upper part of the secondary flame hole.

The burner device according to claim 1, further comprising an air hole provided in a side wall of the combustion chamber and communicated with outside air, and an auxiliary air hole provided in a wall surface of the auxiliary combustion chamber and communicated with air in the combustion chamber.

A Bunsen burner having a primary flame hole, a combustion chamber in which the Bunsen burner is accommodated and provided in a space above the primary flame hole, and a secondary for high combustion provided by opening the upper part of the combustion chamber An auxiliary combustion chamber provided with a flame hole, an auxiliary combustion chamber fixing portion for covering the primary flame hole of the Bunsen burner provided in the combustion chamber and conducting heat of the primary flame to the burner body, and the auxiliary combustion chamber An auxiliary combustion chamber flame hole opened at the top of the auxiliary combustion chamber for weak combustion, the opening of the secondary flame hole has a shape corresponding to the flame distribution at the time of high combustion of the Bunsen burner , the auxiliary combustion chamber flame hole is A burner device having a shape corresponding to the flame distribution of the Bunsen burner during weak combustion, and the load of the auxiliary combustion chamber flame hole being smaller than the load of the primary flame hole and equal to or larger than the load of the secondary flame hole .