JP6849288B2

JP6849288B2 - Burner

Info

Publication number: JP6849288B2
Application number: JP2017046339A
Authority: JP
Inventors: 秀人蓬莱; 昌宏神尾; 雄司今田; 裕樹北野; 佳孝姫路
Original assignee: 日工株式会社
Priority date: 2017-03-10
Filing date: 2017-03-10
Publication date: 2021-03-24
Anticipated expiration: 2037-03-10
Also published as: JP2018151097A

Description

本発明は、液体燃料用の圧力噴霧バーナに関し、特にアスファルトプラントの骨材加熱用のドライヤ等に使用するバーナに関する。 The present invention relates to a pressure spray burner for liquid fuel, and more particularly to a burner used for a dryer for heating aggregate in an asphalt plant.

近年、アスファルト混合物を製造するにあたっては資源の有効活用という観点から、新規骨材に対して道路工事等に伴って発生するアスファルト舗装廃材（以下「廃材」という）を所定割合で混入して製造する場合も多く、その混入率としては約７０〜８０％程度もの高い割合のものもある。廃材を前記のように高い割合にて混入したアスファルト混合物を製造する場合、相対的にアスファルト混合物中に占める新規骨材量は減ることとなり、それに応じて新規骨材加熱用ドライヤのバーナ燃焼量は廃材の混入を行わない通常運転時の燃焼量よりも大幅に絞る必要があるため、前記新規骨材加熱用ドライヤのバーナには、ターンダウン比（最大燃焼量に対する最小燃焼量の比）の大きいもの（例えば１：８程度）が求められることも少なくない。 In recent years, from the viewpoint of effective utilization of resources in the production of asphalt mixture, asphalt pavement waste material (hereinafter referred to as "waste material") generated by road construction etc. is mixed with new aggregate in a predetermined ratio. In many cases, the mixing rate is as high as about 70 to 80%. When producing an asphalt mixture in which waste materials are mixed in a high proportion as described above, the amount of new aggregate in the asphalt mixture is relatively reduced, and the amount of burner burned by the new aggregate heating dryer is correspondingly reduced. Since it is necessary to reduce the amount of combustion in normal operation without mixing waste materials, the burner of the new aggregate heating dryer has a large turndown ratio (ratio of minimum combustion amount to maximum combustion amount). Things (for example, about 1: 8) are often required.

ただし、このような高ターンダウン比のバーナにおいては、最小燃焼量付近にて燃焼を行うと燃焼用空気量が通常時よりも極端に少なくなるため、燃焼用空気の流速低下を来し、場合によっては燃料油と燃焼用空気とを十分に撹拌混合できずに安定した火炎の形成が困難になる懸念がある。 However, in a burner with such a high turndown ratio, if combustion is performed near the minimum combustion amount, the amount of combustion air will be extremely smaller than in normal times, resulting in a decrease in the flow velocity of the combustion air. In some cases, the fuel oil and the combustion air cannot be sufficiently stirred and mixed, and there is a concern that it becomes difficult to form a stable flame.

これに対し、例えば、特許文献１（特開平９−３１０８１３号公報）や、特許文献２（特開２００９−４１８１６号公報）には、バーナ本体を二重筒構造として環状の二次空気用流路を設け、この環状の二次空気用流路には通過する二次空気量を調整する流量調整ダンパーを備え、バーナ燃焼量に応じて前記流量調整ダンパーを開閉制御するようにしたバーナが記載されている。前記バーナによれば、燃焼用空気量の少なくなる低燃焼時においても、前記二次空気用流路を絞ることにより、燃料噴射ノズル周囲を通過する燃焼用空気（一次空気）の流速低下を抑えられ、燃料油と燃焼用空気との撹拌混合性能を落とさずに安定した火炎の形成を可能としている。 On the other hand, for example, in Patent Document 1 (Japanese Patent Laid-Open No. 9-310813) and Patent Document 2 (Japanese Patent Laid-Open No. 2009-41816), the burner body has a double cylinder structure and an annular secondary air flow rate. A burner is described in which a path is provided and a flow rate adjusting damper for adjusting the amount of secondary air passing through the annular secondary air flow path is provided, and the flow rate adjusting damper is opened and closed according to the amount of burner combustion. Has been done. According to the burner, even during low combustion when the amount of combustion air is small, by narrowing the flow path for the secondary air, it is possible to suppress a decrease in the flow velocity of the combustion air (primary air) passing around the fuel injection nozzle. Therefore, it is possible to form a stable flame without deteriorating the stirring and mixing performance of the fuel oil and the combustion air.

特開平９−３１０８１３号公報Japanese Unexamined Patent Publication No. 9-310813 特開２００９−４１８１６号公報JP-A-2009-41816

しかしながら、前記従来のバーナにあっては、二次空気用流路を環状構造としているため、該流路を開閉する流量調整ダンパーは環状の前記流路に沿って所定間隔にて複数配設していると共に、各ダンパー同士を、例えばリンク機構等にて連結し、各ダンパーを同調させながら開閉制御するようにしており、構造的にやや複雑で製造コストやメンテナンス面において幾分不利なものとなっている。 However, in the conventional burner, since the secondary air flow path has an annular structure, a plurality of flow rate adjusting dampers for opening and closing the flow path are arranged at predetermined intervals along the annular flow path. At the same time, each damper is connected to each other by, for example, a link mechanism, and the opening and closing control is performed while synchronizing each damper, which is structurally a little complicated and somewhat disadvantageous in terms of manufacturing cost and maintenance. It has become.

本発明は上記の点に鑑み、比較的簡易な構成ながら安定した火炎形成の可能な高ターンダウン比のバーナを提供することを課題とする。 In view of the above points, it is an object of the present invention to provide a burner having a high turndown ratio capable of forming a stable flame while having a relatively simple configuration.

本発明に係る請求項１記載のバーナでは、単筒構造のバーナ本体の先端開口部に中空で略截頭円錐形状の胴部を有するスロートの小径部側を接続し、前記バーナ本体の内径と略同径で環状の保炎板と、該保炎板の後方に位置する燃料噴射ノズルとをバーナ本体の長手方向に沿って一体的に進退自在に備えると共に、前記バーナ本体内の静圧を検出する静圧センサを備え、該静圧センサにて検出する静圧値を任意の設定値に調整可能なように前記保炎板を前記スロート胴部の範囲内で進退させて二次空気の流路である保炎板外縁部とスロート胴部内周壁との隙間間隔を調整する静圧／保炎板調整制御器を備えたバーナであって、前記静圧／保炎板調整制御器には前記保炎板外縁部側の二次空気の流路を絞らずとも安定燃焼を可能とする略最低限度での燃焼量時の静圧値である所定静圧値を設定し、前記静圧センサにて検出する静圧値が前記所定静圧値以上のときには前記保炎板を前記スロート胴部の大径部側である最前部に位置させて進退動作を行わない一方、前記静圧センサにて検出する静圧値が前記所定静圧値を下回れば該所定静圧値に維持されるように前記保炎板を進退させて保炎板外縁部とスロート胴部内周壁との隙間間隔を調整することを特徴としている。 In the burner according to claim 1 according to the present invention, the small diameter side of the throat having a hollow and substantially cone-shaped body is connected to the tip opening of the burner body having a single cylinder structure, and the inner diameter of the burner body is combined with the inner diameter of the burner body. An annular flame holding plate having substantially the same diameter and a fuel injection nozzle located behind the flame holding plate are integrally provided along the longitudinal direction of the burner body so as to be integrally movable and retractable, and the static pressure inside the burner body is provided. A static pressure sensor for detecting is provided, and the flame holding plate is moved back and forth within the range of the throat body so that the static pressure value detected by the static pressure sensor can be adjusted to an arbitrary set value. A burner equipped with a static pressure / flame retaining plate adjustment controller that adjusts the gap between the outer edge of the flame retaining plate, which is a flow path, and the inner peripheral wall of the throat body. set the predetermined static pressure value is a static pressure during combustion of a substantially minimum to enable stable combustion even with drip flow paths of secondary air in the flame stabilizing plate outer portion, said static When the static pressure value detected by the pressure sensor is equal to or higher than the predetermined static pressure value, the flame holding plate is positioned at the frontmost portion on the large diameter side of the throat body portion to perform the advancing / retreating operation, while the static pressure is not performed. If the static pressure value detected by the sensor falls below the predetermined static pressure value, the flame retaining plate is advanced and retracted so that the predetermined static pressure value is maintained, and the gap between the outer edge of the flame retaining plate and the inner peripheral wall of the throat body is maintained. It is characterized by adjusting.

また、請求項２記載のバーナでは、前記燃料噴射ノズルに燃料を供給する燃料供給配管の流量検出用の流量センサと、前記バーナ本体に燃焼用空気を供給する送風機の送風量検出用の風量センサと、前記送風機の送風量を調整する送風量調整手段と、前記流量センサにて検出する流量に対して所定空気比に相当する設定送風量と前記風量センサにて検出する実際の送風量との差値量に基づいて前記送風量調整手段を介して送風機の送風量を調整する燃料／送風量調整制御器とを備えたことを特徴としている。 Further, in the burner according to claim 2 , a flow rate sensor for detecting the flow rate of the fuel supply pipe that supplies fuel to the fuel injection nozzle and an air volume sensor for detecting the amount of air blown by a blower that supplies combustion air to the burner body. When the blowing amount adjusting means for adjusting the blowing rate of the blower, and the actual air volume that detected by the air volume sensor and setting air volume corresponding to a predetermined air ratio to the flow amount detected by the flow sensor It is characterized by being provided with a fuel / air flow rate adjusting controller that adjusts the air flow rate of the blower via the air flow rate adjusting means based on the difference value amount of the above.

本発明に係る請求項１記載のバーナによれば、バーナ本体の先端開口部に略截頭円錐形状の胴部を有するスロートの小径部側を接続し、前記バーナ本体の内径と略同径の保炎板と、燃料噴射ノズルとをバーナ本体の長手方向に沿って一体的に進退自在に備えると共に、前記バーナ本体内の静圧を検出する静圧センサを備え、該静圧センサにて検出する静圧値を任意の設定値に調整可能なように前記保炎板を進退させて二次空気の流路である保炎板外縁部とスロート胴部内周壁との隙間間隔を調整する静圧／保炎板調整制御器を備えたバーナであって、前記静圧／保炎板調整制御器には前記保炎板外縁部側の二次空気の流路を絞らずとも安定燃焼を可能とする略最低限度での燃焼量時の静圧値である所定静圧値を設定し、前記静圧センサにて検出する静圧値が前記所定静圧値以上のときには前記保炎板を前記スロート胴部の大径部側である最前部に位置させて進退動作を行わない一方、前記静圧センサにて検出する静圧値が前記所定静圧値を下回れば該所定静圧値に維持されるように前記保炎板を進退させて保炎板外縁部とスロート胴部内周壁との隙間間隔を調整するので、燃焼用空気量の少なくなる低燃焼領域においても、保炎板を進退させて保炎板外縁部側の二次空気の流路を絞ってバーナ本体内の静圧値を所定静圧値に維持することにより、バーナ本体内から燃料噴射ノズル周囲を通過して噴射される燃焼用空気の噴射流速も略一定に保て、比較的簡易な構成ながら安定した火炎形成が可能となる。 According to the burner according to claim 1 according to the present invention, the small diameter side of the throat having a body having a substantially head cone shape is connected to the tip opening of the burner body, and the diameter is substantially the same as the inner diameter of the burner body. A flame holding plate and a fuel injection nozzle are integrally provided along the longitudinal direction of the burner body so as to be integrally movable back and forth, and a static pressure sensor for detecting the static pressure inside the burner body is provided and detected by the static pressure sensor. The static pressure is adjusted by advancing and retreating the flame holding plate so that the static pressure value can be adjusted to an arbitrary set value to adjust the gap between the outer edge of the flame holding plate, which is the flow path of the secondary air, and the inner peripheral wall of the throat body. / a burner having a flame stabilizing plate adjusting controller, the stable combustion even with said static pressure / flame holding plate adjusting controller drip the flow path of the secondary air in the flame stabilizing plate outer side A predetermined static pressure value, which is a static pressure value at the time of combustion amount at a substantially minimum possible limit, is set, and when the static pressure value detected by the static pressure sensor is equal to or higher than the predetermined static pressure value, the flame holding plate is used. If the static pressure value detected by the static pressure sensor is lower than the predetermined static pressure value, the static pressure value is reached to the predetermined static pressure value while the throat body is positioned at the frontmost portion on the large diameter side and does not move forward or backward. Since the gap between the outer edge of the flame-retaining plate and the inner peripheral wall of the throat body is adjusted by advancing and retreating the flame-retaining plate so as to be maintained, the flame-retaining plate is advanced and retreated even in a low combustion region where the amount of combustion air is small. By narrowing the flow path of the secondary air on the outer edge side of the flame holding plate and maintaining the static pressure value in the burner body at the predetermined static pressure value, the flame is injected from the inside of the burner body through the vicinity of the fuel injection nozzle. The injection flow velocity of the combustion air can be kept substantially constant, and stable flame formation is possible with a relatively simple configuration.

また、前記所定静圧値として、例えば保炎板外縁部側の二次空気の流路を絞らずとも安定した火炎形成が可能な最低限度付近での燃焼量時の静圧値を設定しておけば、火炎形成の不安定となる低燃焼領域の範囲内に限定して保炎板を進退させることができ、それによって保炎板の進退する調整しろをより有効に活用できて微調整が可能となり、安定した火炎形成が可能となる。 Moreover, as the pre-Symbol predetermined static pressure, for example without narrowed flow paths of secondary air flame stabilizing plate outer side to set the static pressure at the combustion amount in the vicinity of a stable minimum possible flame formation If this is done, the flame holding plate can be advanced and retreated only within the range of the low combustion region where the flame formation becomes unstable, so that the adjustment margin for advancing and retreating the flame retaining plate can be used more effectively and finely adjusted. Is possible, and stable flame formation is possible.

また、請求項２記載のバーナによれば、前記燃料噴射ノズルに燃料を供給する燃料供給配管の流量検出用の流量センサと、前記バーナ本体に燃焼用空気を供給する送風機の送風量検出用の風量センサと、前記送風機の送風量を調整する送風量調整手段と、前記流量センサにて検出する流量に対して所定空気比に相当する設定送風量と前記風量センサにて検出する実際の送風量との差値量に基づいて送風機の送風量を調整する燃料／送風量調整制御器とを備えたので、保炎板外縁部とスロート胴部内周壁との隙間間隔が狭まる方向に調整される際に伴う空気抵抗の増加から、送風機より設定送風量通りにバーナ本体に送風できず、実際に供給される送風量が燃料供給量に対して所定空気比に満たない状態となった場合でも、その不足分相当の空気量を補うように逐次送風機の送風量を調整できて安定した火炎形成が可能となる。 Further , according to the burner according to claim 2 , a flow rate sensor for detecting the flow rate of the fuel supply pipe that supplies fuel to the fuel injection nozzle and a blower for detecting the amount of air blown by the blower that supplies combustion air to the burner body. and air flow sensor, the air blowing amount adjusting means for adjusting the blowing rate of the blower, feeding the actual detection set air volume and at the air volume sensor corresponding to a predetermined air ratio to the flow amount detected by the flow sensor Since it is equipped with a fuel / air flow rate adjustment controller that adjusts the air flow rate of the blower based on the difference value from the air volume, it is adjusted in the direction of narrowing the gap between the outer edge of the flame holding plate and the inner peripheral wall of the throat body. Even if the air resistance cannot be blown from the blower to the burner body according to the set air flow rate due to the increase in air resistance, and the air flow rate actually supplied is less than the specified air ratio with respect to the fuel supply amount. The amount of air blown by the blower can be adjusted sequentially so as to make up for the amount of air corresponding to the shortage, and stable flame formation becomes possible.

本発明に係るバーナの一実施例を示す概略説明図である。It is a schematic explanatory drawing which shows one Example of the burner which concerns on this invention. 最大燃焼量時の保炎板の位置を示す断面図である。It is sectional drawing which shows the position of the flame holding plate at the time of the maximum combustion amount. 最小燃焼量時の保炎板の位置を示す断面図である。It is sectional drawing which shows the position of the flame holding plate at the time of the minimum combustion amount.

本発明に係るバーナにあっては、単筒構造のバーナ本体と、燃焼用空気供給用の送風機とを送風ダクトにて連結する。前記バーナ本体の先端開口部には内径が漸次拡開するテーパ構造となるように、中空で略截頭円錐形状の胴部を有するスロートの小径部側を接続する。また、前記バーナ本体の内径と略同径でかつ環状の保炎板と、該保炎板の後方（バーナ本体側）に所定間隔を置いて配置し、Ａ重油等の液体燃料を噴射する燃料噴射ノズルとをバーナ本体の長手方向に沿って一体的に進退自在に備える。 In the burner according to the present invention, the burner body having a single cylinder structure and the blower for supplying combustion air are connected by a blower duct. The small diameter side of the throat having a hollow and substantially conical body is connected to the tip opening of the burner body so as to have a tapered structure in which the inner diameter gradually expands. Further, a fuel having a diameter substantially the same as the inner diameter of the burner main body and an annular flame holding plate and a fuel for injecting liquid fuel such as A heavy oil are arranged at a predetermined distance behind the flame holding plate (on the burner main body side). The injection nozzle is integrally provided along the longitudinal direction of the burner body so as to be able to move forward and backward.

なお、前記保炎板と燃料噴射ノズルとを一体的に進退させる進退手段としては適宜の手段を採用し得るが、例えば、燃料供給管と戻り管とを内蔵した中空状のロッド部材をバーナ本体の長手方向に沿って進退自在に支持し、該ロッド部材の先端部に燃料噴射ノズルと保炎板とを取り付ける一方、基端部側にロッド部材を進退動作させるステッピングモータ等の駆動モータを具備したものなどを好適に採用することができる。 As an advancing / retreating means for integrally advancing / retreating the flame holding plate and the fuel injection nozzle, an appropriate means can be adopted. For example, a hollow rod member incorporating a fuel supply pipe and a return pipe is used as a burner main body. A fuel injection nozzle and a flame retaining plate are attached to the tip of the rod member, and a drive motor such as a stepping motor for moving the rod member forward and backward is provided on the base end side. And the like can be preferably adopted.

また、前記バーナ本体内の静圧を検出する静圧センサと、該静圧センサにて検出する静圧値が所定値に維持されるように前記保炎板を前記スロート胴部の範囲内において進退させて二次空気の流路である保炎板外縁部とスロート胴部内周壁との隙間間隔を調整する静圧／保炎板調整制御器とを備える。 Further, the static pressure sensor that detects the static pressure in the burner body and the flame holding plate within the range of the throat body so that the static pressure value detected by the static pressure sensor is maintained at a predetermined value. It is provided with a static pressure / flame retaining plate adjustment controller that advances and retreats to adjust the gap between the outer edge of the flame retaining plate, which is the flow path of secondary air, and the inner peripheral wall of the throat body.

なお、前記スロートの全長に対するスロート胴部の長さは適宜決定するとよいが、例えば、スロート胴部の長さを長くとるように形成すれば、保炎板外縁部とテーパ構造のスロート胴部内周壁との隙間間隔の調整しろを多く確保できるようになり微調整が可能となる。 The length of the throat body with respect to the total length of the throat may be appropriately determined. For example, if the length of the throat body is formed to be long, the outer edge of the flame-retaining plate and the inner peripheral wall of the throat body having a tapered structure are formed. It becomes possible to secure a large amount of adjustment margin for the gap between the and, and fine adjustment becomes possible.

また、好ましくは、前記静圧／保炎板調整制御器に少なくとも安定燃焼を可能とする所定静圧値を予め設定しておき、前記静圧センサにて検出する静圧値が前記所定静圧値を下回れば、該所定静圧値に維持されるように前記保炎板を進退させて前記保炎板外縁部とスロート胴部内周壁との隙間間隔を調整する制御としてもよい。このような制御とすることにより、前記所定静圧値として、例えば安定した火炎形成が可能な最低燃焼量時の静圧値を設定しておけば、十分に安定した火炎形成が可能な高燃焼領域から中間燃焼領域付近にかけては保炎板の進退動作は行わない一方、火炎形成が不安定となる低燃焼領域の範囲内に限定して保炎板の進退動作を行うこととなり、保炎板の進退する調整しろをより有効に生かせて微調整が可能なものとなる。 Further, preferably, a predetermined static pressure value that enables stable combustion is set in advance in the static pressure / flame holding plate adjustment controller, and the static pressure value detected by the static pressure sensor is the predetermined static pressure. If the value is lower than the value, the flame holding plate may be advanced and retreated so as to maintain the predetermined static pressure value, and the clearance between the outer edge of the flame holding plate and the inner peripheral wall of the throat body may be adjusted. With such control, if the static pressure value at the minimum combustion amount that enables stable flame formation is set as the predetermined static pressure value, high combustion that enables sufficiently stable flame formation is possible. While the flame-retaining plate does not move forward and backward from the region to the vicinity of the intermediate combustion region, the flame-retaining plate moves back and forth only within the range of the low combustion region where flame formation becomes unstable. It becomes possible to make fine adjustments by making more effective use of the adjustment margin for advancing and retreating.

また、好ましくは、前記燃料噴射ノズルに燃料を供給する燃料供給配管の流量検出用の流量センサと、前記送風機の送風量検出用の風量センサと、前記送風機の送風量を調整する、例えばインバータ式の送風機等の送風量調整手段と、前記流量センサにて検出する燃料供給量に対して所定空気比に相当する設定送風量と前記風量センサにて検出する実際の送風量との差値量に基づいて前記送風量調整手段を介して送風機の送風量を調整する燃料／送風量調整制御器を備えるようにしてもよい。 Further, preferably, the flow rate sensor for detecting the flow rate of the fuel supply pipe that supplies fuel to the fuel injection nozzle, the air volume sensor for detecting the air flow rate of the blower, and the air flow rate of the blower are adjusted, for example, an inverter type. The difference between the air volume adjusting means such as the blower and the set air volume corresponding to the predetermined air ratio to the fuel supply amount detected by the flow rate sensor and the actual air volume detected by the air volume sensor. Based on this, a fuel / air flow rate adjusting controller that adjusts the air flow rate of the blower via the air flow rate adjusting means may be provided.

このようにすれば、保炎板外縁部とスロート胴部内周壁との隙間間隔が狭まる方向へ調整される際に伴う空気抵抗の増加から、送風機にて設定送風量通りにバーナ本体に送風できず、実際に供給される送風量が所定空気比に満たない状態となった場合でも、その不足分相当の空気量を補えるように逐次送風機の送風量を補正できて安定した火炎形成が可能となる。 In this way, due to the increase in air resistance that accompanies the adjustment in the direction of narrowing the gap between the outer edge of the flame holding plate and the inner peripheral wall of the throat body, it is not possible to blow air to the burner body according to the set air volume with the blower. Even if the amount of air actually supplied is less than the predetermined air ratio, the amount of air blown by the blower can be corrected sequentially so as to compensate for the shortage, and stable flame formation becomes possible. ..

そして、上記構成のバーナの運転時には、先ず、前記静圧／保炎板調整制御器に所定の静圧値（例えば、最大燃焼量時の静圧値）を設定する。そして、例えば、バーナ燃焼量を高〜中間燃焼領域より低燃焼領域に下げるとそれに応じて送風機からの送風量と共にバーナ本体内の静圧は低下するが、それを前記静圧センサが検出すると前記保炎板を後退させる。前記スロート胴部の内径は後方（バーナ本体側）に向けて漸次縮径するテーパ構造としているため、保炎板の後退に伴って保炎板外縁部とスロート胴部内周壁との隙間間隔は徐々に狭まって静圧は上昇していき、予め設定した前記所定値に維持されることとなる。 Then, when operating the burner having the above configuration, first, a predetermined static pressure value (for example, a static pressure value at the maximum combustion amount) is set in the static pressure / flame holding plate adjustment controller. Then, for example, when the burner combustion amount is lowered from the high to intermediate combustion region to the low combustion region, the static pressure in the burner body decreases with the amount of air blown from the blower, but when the static pressure sensor detects it, the static pressure sensor is described. Retract the flame retaining plate. Since the inner diameter of the throat body has a tapered structure that gradually shrinks toward the rear (burner body side), the gap between the outer edge of the flame retaining plate and the inner peripheral wall of the throat body gradually decreases as the flame retaining plate retracts. The static pressure gradually increases, and is maintained at the predetermined value set in advance.

これによって、燃焼用空気量の極端に少なくなる最小燃焼量付近にあっても、バーナ本体から噴射される燃焼用空気の噴射流速を高〜中間燃焼量時と同等程度に維持でき、燃料油と燃焼用空気との撹拌混合性を落とさずに安定した火炎形成が可能となる。 As a result, the injection flow velocity of the combustion air injected from the burner body can be maintained at the same level as that at the time of high to intermediate combustion amount even in the vicinity of the minimum combustion amount where the amount of combustion air is extremely small, and the fuel oil and Stable flame formation is possible without deteriorating the agitation mixture with the combustion air.

このように、バーナ本体の先端開口部に中空で略截頭円錐形状の胴部を有するスロートの小径部側を接続する一方、バーナ本体の内径と略同径の保炎板を前記スロート胴部の範囲内において進退自在に備えると共に、バーナ本体内の静圧値が略一定に維持されるように前記保炎板を進退させて保炎板外縁部とスロート胴部内周壁との隙間間隔を調整する構成としたので、比較的簡易な構成でありながら低燃焼領域で燃焼した場合でもバーナ本体からの燃焼用空気の噴射流速も略一定に保て、高ターンダウン比のバーナであっても最大燃焼領域から最小燃焼領域に亘って安定した燃焼状態を維持できる。 In this way, the small diameter side of the throat having a hollow and substantially cone-shaped body is connected to the tip opening of the burner body, while the flame holding plate having a diameter substantially the same as the inner diameter of the burner body is connected to the throat body. The flame retaining plate is advanced and retracted so that the static pressure value in the burner body is maintained substantially constant, and the gap between the outer edge of the flame retaining plate and the inner peripheral wall of the throat body is adjusted. Even if the burner has a relatively simple configuration, the injection flow velocity of the combustion air from the burner body can be kept substantially constant even when burning in a low combustion region, and even a burner with a high turndown ratio can be used at the maximum. A stable combustion state can be maintained from the combustion region to the minimum combustion region.

以下、本発明の一実施例を図面に基づいて説明する。 Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

図中の１は、例えば、アスファルトプラントの骨材加熱用ドライヤに設置される本発明の高ターンダウン比のバーナであって、単筒構造のバーナ本体２と、燃焼用空気供給用の送風機３とを送風ダクト４にて連結している。前記バーナ本体２の先端開口部には内径が漸次拡開するテーパ構造となるように、中空で略截頭円錐形状の胴部５ａを有するスロート５の小径部側を接続している。また、バーナ本体２の略中心部（円筒軸芯部）には、燃料供給管と戻り管（図示せず）とを内蔵した中空のロッド部材６を貫挿していると共に、該ロッド部材６をその上下から複数のガイドローラ７にて挟持し、図１中の太線矢印にて示すように、バーナ本体２の長手方向に沿って進退自在に支持している。 Reference numeral 1 in the figure is, for example, a burner having a high turndown ratio of the present invention installed in an aggregate heating dryer of an asphalt plant, which is a single-cylinder burner main body 2 and a blower 3 for supplying combustion air. Is connected by a ventilation duct 4. The tip opening of the burner body 2 is connected to the small diameter side of the throat 5 having a hollow and substantially conical body portion 5a so as to have a tapered structure in which the inner diameter gradually expands. Further, a hollow rod member 6 containing a fuel supply pipe and a return pipe (not shown) is inserted into the substantially central portion (cylindrical shaft core portion) of the burner main body 2, and the rod member 6 is inserted. It is sandwiched by a plurality of guide rollers 7 from above and below, and is supported so as to be able to advance and retreat along the longitudinal direction of the burner main body 2 as shown by the thick arrow in FIG.

前記ロッド部材６の先端部には燃料噴射ノズル８と、該燃料噴射ノズル８の前方に取り付け金具９を介して所定間隔を置いて配置し、バーナ本体２の内径と略同径でかつ環状の保炎板１０とを固着している。なお、前記燃料噴射ノズル８と保炎板１０との間隔は、油噴霧角等を考慮しつつ、燃焼試験等を通じて適当な火炎形状が形成されるように適宜決定するとよい。 A fuel injection nozzle 8 is arranged at the tip of the rod member 6 at a predetermined distance in front of the fuel injection nozzle 8 via a mounting bracket 9, and has substantially the same diameter as the inner diameter of the burner main body 2 and is annular. The flame holding plate 10 is fixed. The distance between the fuel injection nozzle 8 and the flame holding plate 10 may be appropriately determined so that an appropriate flame shape is formed through a combustion test or the like while considering the oil spray angle or the like.

一方、バーナ本体２の後端部を貫通して後方へ突出させたロッド基端部１１には、ロッド部材６内の燃料供給管と戻り管とにそれぞれ接続させるように燃料供給配管１２と燃料戻り配管１３とを連結していると共に、前記ロッド部材６をバーナ本体２の長手方向に沿って進退動作させる進退手段１４を備えている。 On the other hand, the rod base end portion 11 that penetrates the rear end portion of the burner main body 2 and protrudes rearward is connected to the fuel supply pipe 12 and the fuel so as to be connected to the fuel supply pipe and the return pipe in the rod member 6, respectively. In addition to connecting the return pipe 13, the rod member 6 is provided with advancing / retreating means 14 for advancing / retreating the rod member 6 along the longitudinal direction of the burner main body 2.

前記進退手段１４は適宜の構成を採用し得るが、例えば、図１に示すように、バーナ本体２の後端部より後方へ延設した支持体１５と、該支持体１５と平行に軸支したスクリュ軸１６と、該スクリュ軸１６を回転駆動させるステッピングモータ１７等から構成したものを好適に採用できる。図中の１８は、前記ロッド基端部１１とスクリュ軸１６とを連結する連結片であって、該連結片１８の連結部内面側には前記スクリュ軸１６のスクリュ溝と螺合する溝部（図示せず）を刻設しており、前記ステッピングモータ１７にてスクリュ軸１６を正・逆回転させることで連結片１８を介して前記ロッド部材６をバーナ本体２長手方向に沿って所定位置へ進退可能としている。 The advancing / retreating means 14 may adopt an appropriate configuration. For example, as shown in FIG. 1, a support 15 extending rearward from the rear end portion of the burner main body 2 and a shaft support parallel to the support 15. A screw shaft 16 formed of the screw shaft 16 and a stepping motor 17 or the like for rotationally driving the screw shaft 16 can be preferably adopted. Reference numeral 18 in the drawing is a connecting piece for connecting the rod base end portion 11 and the screw shaft 16, and a groove portion (screw groove) screwed with the screw groove of the screw shaft 16 is provided on the inner surface side of the connecting portion of the connecting piece 18. (Not shown) is engraved, and the screw shaft 16 is rotated forward and reverse by the stepping motor 17, so that the rod member 6 is moved to a predetermined position along the longitudinal direction of the burner body 2 via the connecting piece 18. It is possible to move forward and backward.

また、図中の１９は、前記ロッド部材６の貫通するバーナ本体２基端部の貫通孔（図示せず）の隙間からバーナ本体２内部の高圧の燃焼用空気の噴出を防止する気密用のシール部材であって、本実施例においては、ロッド部材６の進退動作を妨げないように、例えば伸縮自在な蛇腹構造としている。 Further, 19 in the drawing is for airtightness to prevent high-pressure combustion air inside the burner main body 2 from being ejected from a gap (not shown) at the end of two burner main bodies through which the rod member 6 penetrates. It is a seal member, and in this embodiment, it has, for example, a stretchable bellows structure so as not to interfere with the advancing / retreating operation of the rod member 6.

図中の２０はバーナ本体２内の静圧を検出する静圧センサ、２１は静圧／保炎板調整制御器であって、該静圧／保炎板調整制御器２１では前記静圧センサ２０にて検出する静圧値を逐次取り込み、取り込んだ静圧値が所定値、例えば最大燃焼量時における静圧値（例えば、約３００ｍｍＡｑ）に維持されるように前記進退手段１４を介してロッド部材６先端部の保炎板１０をスロート胴部５ａの範囲内において進退させ、二次空気の流路である保炎板外縁部１０ａとスロート胴部５ａ内周壁との隙間Ａの間隔を調整するようにしている。 In the figure, 20 is a static pressure sensor that detects the static pressure in the burner main body 2, 21 is a static pressure / flame holding plate adjustment controller, and the static pressure / flame holding plate adjustment controller 21 is the static pressure sensor. The static pressure value detected in 20 is sequentially taken in, and the rod is maintained through the advancing / retreating means 14 so that the taken static pressure value is maintained at a predetermined value, for example, the static pressure value at the maximum combustion amount (for example, about 300 mmAq). The flame-retaining plate 10 at the tip of the member 6 is advanced and retracted within the range of the throat body 5a, and the distance between the gap A between the flame-retaining plate outer edge 10a, which is the secondary air flow path, and the inner peripheral wall of the throat body 5a is adjusted. I try to do it.

なお、前記静圧／保炎板調整制御器２１に少なくとも安定燃焼を可能とする所定静圧値を予め設定しておき、前記静圧センサ２０にて検出する静圧値が前記所定静圧値を下回れば、該所定静圧値に復帰、維持されるように前記保炎板１０を進退させ、二次空気の流路である保炎板外縁部１０ａとスロート胴部５ａ内周壁との隙間Ａ間隔を調整する制御とすることもできる。前記制御を採用することにより、前記所定静圧値として、例えば、燃焼試験等を通じて知見される、保炎板外縁部１０ａ側の二次空気の流路を絞らずとも安定した火炎形成が可能な最低限度付近での燃焼量時の静圧値（例えば、約２００ｍｍＡｑ）を設定しておけば、十分に安定した火炎形成が可能な高燃焼領域から中間燃焼領域付近にかけては保炎板１０の進退動作は行われなくなる一方、火炎形成が不安定となる低燃焼領域の範囲内に限って保炎板１０の進退動作が行われることとなり、保炎板１０の調整しろをより有効に生かせて微調整が可能となる。 A predetermined static pressure value that enables stable combustion is set in advance in the static pressure / flame holding plate adjustment controller 21, and the static pressure value detected by the static pressure sensor 20 is the predetermined static pressure value. If it falls below the above value, the flame holding plate 10 is advanced and retreated so as to return to and maintain the predetermined static pressure value, and the gap between the outer edge portion 10a of the flame retaining plate, which is the flow path of the secondary air, and the inner peripheral wall of the throat body 5a. It can also be controlled to adjust the A interval. By adopting the above control, it is possible to form a stable flame as the predetermined static pressure value without narrowing the flow path of the secondary air on the outer edge portion 10a side of the flame holding plate, which is found through, for example, a combustion test. If the static pressure value (for example, about 200 mmAq) at the time of combustion amount near the minimum limit is set, the flame holding plate 10 advances and retreats from the high combustion region where sufficiently stable flame formation is possible to the vicinity of the intermediate combustion region. While the operation is no longer performed, the flame holding plate 10 is moved forward and backward only within the range of the low combustion region where the flame formation becomes unstable, and the adjustment margin of the flame holding plate 10 is used more effectively to make a slight adjustment. Adjustment is possible.

また、前記ロッド部材６にＡ重油や灯油等の燃料油を供給する燃料供給配管１２はその途中に燃料供給ポンプ２２及び流量センサ２３を介在させて他端部を燃油タンク２４に連結している一方、併設した燃料戻り配管１３はその途中に流量調整弁２５を介在させて他端部を前記燃料供給ポンプ２２上流側の燃料供給配管１２に連結しており、コントロールモータ２６にて前記流量調整弁２５の開度を調整して燃料油の戻り量を調整することにより、ロッド部材６先端部の燃料噴射ノズル８からの燃料油の噴射速度をあまり変動させることなく噴射量のみを調整可能としている。 Further, the fuel supply pipe 12 for supplying fuel oil such as heavy oil A or kerosene to the rod member 6 has a fuel supply pump 22 and a flow sensor 23 interposed therebetween, and the other end thereof is connected to the fuel tank 24. On the other hand, the adjacent fuel return pipe 13 has a flow rate adjusting valve 25 interposed in the middle thereof, and the other end thereof is connected to the fuel supply pipe 12 on the upstream side of the fuel supply pump 22, and the flow rate is adjusted by the control motor 26. By adjusting the opening degree of the valve 25 to adjust the return amount of the fuel oil, it is possible to adjust only the injection amount without changing the injection speed of the fuel oil from the fuel injection nozzle 8 at the tip of the rod member 6 so much. There is.

また、前記送風機３の吸気口２７には略直管構造の吸気管２８を接続し、該吸気管２８の途中には送風量検出用の風量センサ２９を備えると共に、送風機３の駆動モータ３０には送風量調整手段である回転数制御用のインバータ３１を備えており、該インバータ３１にて前記駆動モータ３０の回転数を調整することにより、送風量調整用ダンパー等を要することなくバーナ燃焼量に見合った送風量をバーナ本体２に供給可能としている。 Further, an intake pipe 28 having a substantially straight pipe structure is connected to the intake port 27 of the blower 3, and an air volume sensor 29 for detecting the air volume is provided in the middle of the intake pipe 28, and the drive motor 30 of the blower 3 is provided. Is equipped with an inverter 31 for controlling the number of revolutions, which is a means for adjusting the amount of air blown, and by adjusting the number of revolutions of the drive motor 30 with the inverter 31, the amount of burner combustion without the need for a damper for adjusting the amount of air blown. It is possible to supply the amount of air blown to the burner main body 2 in accordance with the above.

図中の３２は燃料／送風量調整制御器であって、該燃料／送風量調整制御器３２では前記流量調整弁２５にて調整して前記流量センサ２３にて検出する燃料供給量を逐次取り込み、この取り込んだ燃料供給量に対して予め設定した所定空気比（例えば約１．２程度）に相当する設定送風量を算出し、この算出した設定送風量と前記風量センサ２９にて検出する実際の送風量との差値量に基づき、前記インバータ３１を介して送風機３から供給する送風量を調整すると好ましい。 Reference numeral 32 denotes a fuel / air volume adjusting controller, and the fuel / air volume adjusting controller 32 sequentially captures the fuel supply amount detected by the flow rate sensor 23 after being adjusted by the flow rate adjusting valve 25. , The set air flow rate corresponding to a predetermined air ratio (for example, about 1.2) set in advance with respect to the taken-in fuel supply amount is calculated, and the calculated set air flow rate and the actual air volume sensor 29 detect. It is preferable to adjust the amount of air supplied from the blower 3 via the inverter 31 based on the amount of difference from the amount of air blown.

こうすることにより、保炎板外縁部１０ａとスロート胴部５ａ内周壁との隙間Ａの間隔が狭まる方向へ調整される際に伴う空気抵抗の増加から、送風機３にて設定送風量通りに送風できず、実際の送風量が所定空気比に満たない状態となった場合でも、その不足分の空気量を補えるように逐次送風機３の送風量を修正でき、送風量不足による燃焼不良や失火等の不具合を未然に防止できて安定した火炎形成が可能となる。 By doing so, the air resistance increases when the distance between the gap A between the outer edge portion 10a of the flame holding plate and the inner peripheral wall of the throat body 5a is narrowed, so that the blower 3 blows air according to the set air volume. Even if the actual air volume is less than the predetermined air ratio, the air volume of the blower 3 can be corrected so as to compensate for the shortage of air, resulting in poor combustion or misfire due to insufficient air volume. It is possible to prevent the troubles of the above and to form a stable flame.

そして、上記構成のバーナ１運転時には、例えば、バーナ燃焼量を増加するとそれに応じて送風機３からの送風量と共にバーナ本体２内部の静圧は高くなるが、それを静圧センサ２０が検出すると、前記静圧／保炎板調整制御器２１は前記進退手段１４のステッピングモータ１７を介してロッド部材６先端部の保炎板１０を、図２中の太線矢印にて示すように（図中の左方向に）前進させる。 Then, during the operation of the burner 1 having the above configuration, for example, when the burner combustion amount is increased, the static pressure inside the burner main body 2 increases with the amount of air blown from the blower 3, but when the static pressure sensor 20 detects it, The static pressure / flame retaining plate adjustment controller 21 communicates the flame retaining plate 10 at the tip of the rod member 6 via the stepping motor 17 of the advancing / retreating means 14 as shown by a thick arrow in FIG. 2 (in the figure). Move forward (to the left).

前記スロート胴部５ａの内径は、前方（図中の左方向）に向けて漸次拡開する略テーパ構造としているため、保炎板１０の前進動作に伴って保炎板外縁部１０ａとスロート胴部５ａ内周壁との隙間Ａの間隔は徐々に広がっていき、それと共にバーナ本体２内の静圧は低下していく。そして、前記静圧が所定値（例えば、約３００ｍｍＡｑ）に復帰すれば、その位置で保炎板１０を停止させる。 Since the inner diameter of the throat body 5a has a substantially tapered structure that gradually expands toward the front (leftward in the drawing), the flame holding plate outer edge 10a and the throat body are formed as the flame retaining plate 10 moves forward. The distance between the gap A and the inner peripheral wall of the portion 5a gradually widens, and at the same time, the static pressure inside the burner main body 2 decreases. Then, when the static pressure returns to a predetermined value (for example, about 300 mmAq), the flame holding plate 10 is stopped at that position.

このとき、バーナ火炎の形成される保炎板１０前方側には、図２に示すように、燃料噴射ノズル８周囲を通過して保炎板１０中心開口部Ｂへ抜け出る燃焼用空気（一次空気）と共に、保炎板外縁部１０ａとスロート胴部５ａ内周壁との隙間Ａを通過する二次空気とが供給され、安定した火炎形成が可能となる。 At this time, as shown in FIG. 2, on the front side of the flame holding plate 10 on which the burner flame is formed, combustion air (primary air) that passes around the fuel injection nozzle 8 and escapes to the central opening B of the flame holding plate 10. ), And the secondary air passing through the gap A between the outer edge portion 10a of the flame holding plate and the inner peripheral wall of the throat body portion 5a is supplied, and stable flame formation becomes possible.

一方、バーナ燃焼量を減少するとそれに応じて送風機３からの送風量と共にバーナ本体２内部の静圧は低下するが、それを静圧センサ２０が検出すると、前記静圧／保炎板調整制御器２１は前記進退手段１４のステッピングモータ１７を介してロッド部材６先端部の保炎板１０を、図３中の太線矢印にて示すように（図中の右方向に）後退させる。 On the other hand, when the amount of burner combustion is reduced, the static pressure inside the burner main body 2 decreases accordingly with the amount of air blown from the blower 3, but when the static pressure sensor 20 detects it, the static pressure / flame holding plate adjustment controller 21 retracts the flame holding plate 10 at the tip of the rod member 6 via the stepping motor 17 of the advancing / retreating means 14 (to the right in the drawing) as shown by the thick arrow in FIG.

そして、保炎板１０の後退動作に伴って保炎板外縁部１０ａとスロート胴部５ａ内周壁との隙間Ａの間隔は徐々に狭まっていき、それと共にバーナ本体２内の静圧は上昇していく。そして、前記静圧が所定値に復帰すれば、その位置で保炎板１０を停止させる。 Then, as the flame retaining plate 10 retracts, the distance between the gap A between the flame retaining plate outer edge portion 10a and the inner peripheral wall of the throat body 5a gradually narrows, and at the same time, the static pressure inside the burner body 2 increases. To go. Then, when the static pressure returns to a predetermined value, the flame holding plate 10 is stopped at that position.

なお、バーナ燃焼量を最小燃焼量付近まで絞った場合であれば、図３に示すように、前記保炎板１０はバーナ本体２内に収まる位置まで後退することになる。このとき、保炎板外縁部１０ａとスロート胴部５ａ内周壁とはほぼ隙間なく密接した状態、即ち二次空気の流路である隙間Ａはほぼ閉鎖状態にあり、その結果、保炎板１０前方側には、専ら燃料噴射ノズル８周囲を通過して保炎板１０中心開口部Ｂへ抜け出る流路に限定されることとなり、バーナ本体２内の静圧値は前記同様所定値に復帰、維持される。 When the burner combustion amount is reduced to the vicinity of the minimum combustion amount, as shown in FIG. 3, the flame holding plate 10 is retracted to a position where it can be accommodated in the burner main body 2. At this time, the outer edge portion 10a of the flame holding plate and the inner peripheral wall of the throat body 5a are in close contact with each other with almost no gap, that is, the gap A which is the flow path of the secondary air is almost closed, and as a result, the flame holding plate 10 On the front side, the flow path is limited to the flow path that passes around the fuel injection nozzle 8 and exits to the central opening B of the flame holding plate 10, and the static pressure value in the burner body 2 returns to the predetermined value as described above. Be maintained.

これによって、高ターンダウン比のバーナにおいては、燃焼用空気量が最大燃焼量時と比較して極端に少なくなる最小燃焼量付近にあっても、バーナ本体２から噴射される燃焼用空気の噴射流速を高〜中間燃焼量時と同等程度に維持でき、燃料油と燃焼用空気との撹拌混合性を落とすことなく良好に燃焼させることが可能となる。 As a result, in a burner with a high turndown ratio, even if the amount of combustion air is near the minimum combustion amount, which is extremely smaller than that at the time of the maximum combustion amount, the combustion air injected from the burner main body 2 is injected. The flow velocity can be maintained at the same level as that at the time of high to intermediate combustion amount, and good combustion can be performed without deteriorating the stirring mixture of the fuel oil and the combustion air.

なお、前記保炎板１０と燃料噴射ノズル８とは、両者の間隔を維持しながら一体的に進退する構成としているため、例えバーナ燃焼量に応じて保炎板１０の位置を進退させたとしても、油噴霧角や火炎形状等への影響を最小限に抑えることができる。 Since the flame holding plate 10 and the fuel injection nozzle 8 are configured to move forward and backward integrally while maintaining the distance between them, it is assumed that the position of the flame holding plate 10 is moved forward and backward according to the amount of burner combustion. However, the influence on the oil spray angle, flame shape, etc. can be minimized.

本発明は、液体燃料用の圧力噴霧式のバーナに対して広く利用できる。 The present invention can be widely used for pressure spray burners for liquid fuels.

１…バーナ２…バーナ本体
３…送風機４…送風ダクト
５…スロート５ａ…スロート胴部
６…ロッド部材８…燃料噴射ノズル
１０…保炎板１０ａ…保炎板外縁部
１２…燃料供給配管１３…燃料戻り配管
１４…進退手段２０…静圧センサ
２１…静圧／保炎板調整制御器２３…流量センサ
２９…風量センサ３１…インバータ（送風量調整手段）
３２…燃料／送風量調整制御器 1 ... Burner 2 ... Burner body 3 ... Blower 4 ... Blower duct 5 ... Throat 5a ... Throat body 6 ... Rod member 8 ... Fuel injection nozzle 10 ... Flame retaining plate 10a ... Flame retaining plate outer edge 12 ... Fuel supply piping 13 ... Fuel return pipe 14 ... Advancing / retreating means 20 ... Static pressure sensor 21 ... Static pressure / flame retaining plate adjustment controller 23 ... Flow sensor 29 ... Air volume sensor 31 ... Inverter (air flow volume adjusting means)
32 ... Fuel / air volume adjustment controller

Claims

単筒構造のバーナ本体の先端開口部に中空で略截頭円錐形状の胴部を有するスロートの小径部側を接続し、前記バーナ本体の内径と略同径で環状の保炎板と、該保炎板の後方に位置する燃料噴射ノズルとをバーナ本体の長手方向に沿って一体的に進退自在に備えると共に、前記バーナ本体内の静圧を検出する静圧センサを備え、該静圧センサにて検出する静圧値を任意の設定値に調整可能なように前記保炎板を前記スロート胴部の範囲内で進退させて二次空気の流路である保炎板外縁部とスロート胴部内周壁との隙間間隔を調整する静圧／保炎板調整制御器を備えたバーナであって、前記静圧／保炎板調整制御器には前記保炎板外縁部側の二次空気の流路を絞らずとも安定燃焼を可能とする略最低限度での燃焼量時の静圧値である所定静圧値を設定し、前記静圧センサにて検出する静圧値が前記所定静圧値以上のときには前記保炎板を前記スロート胴部の大径部側である最前部に位置させて進退動作を行わない一方、前記静圧センサにて検出する静圧値が前記所定静圧値を下回れば該所定静圧値に維持されるように前記保炎板を進退させて保炎板外縁部とスロート胴部内周壁との隙間間隔を調整することを特徴とするバーナ。 The small diameter side of the throat having a hollow and substantially conical body is connected to the tip opening of the burner body having a single cylinder structure, and an annular flame holding plate having a diameter substantially the same as the inner diameter of the burner body and the flame holding plate. A fuel injection nozzle located behind the flame holding plate is integrally provided so as to be able to move forward and backward along the longitudinal direction of the burner body, and a static pressure sensor for detecting the static pressure inside the burner body is provided. The flame holding plate is moved back and forth within the range of the throat body so that the static pressure value detected in the above can be adjusted to an arbitrary set value. It is a burner provided with a static pressure / flame retaining plate adjustment controller that adjusts the gap between the inner peripheral wall of the portion, and the static pressure / flame retaining plate adjustment controller is provided with the secondary air on the outer edge side of the flame retaining plate. set the predetermined static pressure value is a static pressure during combustion of a substantially minimum to enable stable combustion even with drip flow path, the static pressure value detected by the static pressure sensor is predetermined When the static pressure value is equal to or higher than the static pressure value, the flame holding plate is positioned at the foremost portion on the large diameter side of the throat body to not advance or retreat, while the static pressure value detected by the static pressure sensor is the predetermined static pressure value. A burner characterized in that the flame holding plate is advanced and retracted so that the flame holding plate is maintained at a predetermined static pressure value when the pressure value falls below the pressure value, and the gap between the outer edge of the flame holding plate and the inner peripheral wall of the throat body is adjusted.

前記燃料噴射ノズルに燃料を供給する燃料供給配管の流量検出用の流量センサと、前記バーナ本体に燃焼用空気を供給する送風機の送風量検出用の風量センサと、前記送風機の送風量を調整する送風量調整手段と、前記流量センサにて検出する流量に対して所定空気比に相当する設定送風量と前記風量センサにて検出する実際の送風量との差値量に基づいて前記送風量調整手段を介して送風機の送風量を調整する燃料／送風量調整制御器とを備えたことを特徴とする請求項１記載のバーナ。 The flow rate sensor for detecting the flow rate of the fuel supply pipe that supplies fuel to the fuel injection nozzle, the air volume sensor for detecting the air flow rate of the blower that supplies combustion air to the burner body, and the air flow rate of the blower are adjusted. The air flow rate adjustment means and the air flow rate adjustment based on the difference value between the set air flow rate corresponding to the predetermined air ratio with respect to the flow rate detected by the flow rate sensor and the actual air flow rate detected by the air volume sensor. The burner according to claim 1, further comprising a fuel / air flow rate adjusting controller for adjusting the air flow rate of the blower via means.