JPH0421094B2 - - Google Patents
Info
- Publication number
- JPH0421094B2 JPH0421094B2 JP60146002A JP14600285A JPH0421094B2 JP H0421094 B2 JPH0421094 B2 JP H0421094B2 JP 60146002 A JP60146002 A JP 60146002A JP 14600285 A JP14600285 A JP 14600285A JP H0421094 B2 JPH0421094 B2 JP H0421094B2
- Authority
- JP
- Japan
- Prior art keywords
- air
- fuel ratio
- flame
- current
- rod sensor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000000446 fuel Substances 0.000 claims description 48
- 238000002485 combustion reaction Methods 0.000 claims description 21
- 238000001514 detection method Methods 0.000 claims description 20
- 238000005259 measurement Methods 0.000 claims description 9
- 238000010586 diagram Methods 0.000 description 6
- 239000000203 mixture Substances 0.000 description 4
- 239000000567 combustion gas Substances 0.000 description 3
- 206010021143 Hypoxia Diseases 0.000 description 1
- 230000005856 abnormality Effects 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23N—REGULATING OR CONTROLLING COMBUSTION
- F23N5/00—Systems for controlling combustion
- F23N5/02—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium
- F23N5/12—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium using ionisation-sensitive elements, i.e. flame rods
- F23N5/123—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium using ionisation-sensitive elements, i.e. flame rods using electronic means
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23N—REGULATING OR CONTROLLING COMBUSTION
- F23N1/00—Regulating fuel supply
- F23N1/02—Regulating fuel supply conjointly with air supply
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23N—REGULATING OR CONTROLLING COMBUSTION
- F23N2225/00—Measuring
- F23N2225/26—Measuring humidity
- F23N2225/30—Measuring humidity measuring lambda
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23N—REGULATING OR CONTROLLING COMBUSTION
- F23N2229/00—Flame sensors
- F23N2229/16—Flame sensors using two or more of the same types of flame sensor
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23N—REGULATING OR CONTROLLING COMBUSTION
- F23N5/00—Systems for controlling combustion
- F23N5/003—Systems for controlling combustion using detectors sensitive to combustion gas properties
- F23N5/006—Systems for controlling combustion using detectors sensitive to combustion gas properties the detector being sensitive to oxygen
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Control Of Combustion (AREA)
Description
【発明の詳細な説明】
産業上の利用分野
本発明はガス、石油等燃焼機器の燃焼を制御す
る燃焼制御装置に関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a combustion control device for controlling combustion of gas, oil, etc. combustion equipment.
従来の技術
従来の燃焼制御装置は第５図に示すように、燃
焼用混合気体の流出するバーナ１と、このバーナ
１から形成される炎の外炎に触れる位置に設置し
たフレームロツド２とを電源３と電流計４とを直
列に接続した回路に組込んだ構成であり、バーナ
１から流出する燃焼用混合気体が着火して炎を形
成するのであるが、この炎に電導性がある為、前
記電流計４の回路が形成されて、この回路に電流
が流れる。この電流の大きさは炎内のイオン濃
度、即ち燃料と空気との混合比（以後、空燃比と
記す）によつて決定されるのであるから電流計４
の電流値により空燃比を知ることができる。この
電流の大きさに応じてバーナ１に供給される燃焼
用混合気体の空燃比を調整する調整装置５を設け
て空燃比が一定になるように構成したものであ
る。（例えば、特公昭46−36947号公報）
発明が解決しようとする問題点
しかしながら、炎イオン電流と空燃比の関係は
第６図に示す様に空燃比Ｐ＝Poでイオン電流Ifは
ピーク値If＝Ifoとなり、１対１の関数にならな
いことが知られており、上記の様な従来の構成で
は、If＝If1のときにＰ＝P1なのかＰ＝P2なのか
判別できないために誤つた調整を行なう可能性が
あるという問題点を有していた。BACKGROUND TECHNOLOGY As shown in FIG. 5, a conventional combustion control device connects a burner 1 from which a combustion gas mixture flows out and a flame rod 2 installed in a position where it touches the outer flame of the flame formed from this burner 1. 3 and an ammeter 4 are connected in series, and the combustion gas mixture flowing out from the burner 1 ignites to form a flame, but since this flame has electrical conductivity, A circuit for the ammeter 4 is formed, and a current flows through this circuit. The magnitude of this current is determined by the ion concentration in the flame, that is, the mixture ratio of fuel and air (hereinafter referred to as air-fuel ratio), so the ammeter 4
The air-fuel ratio can be determined by the current value. An adjustment device 5 is provided to adjust the air-fuel ratio of the combustion gas mixture supplied to the burner 1 in accordance with the magnitude of this current, so that the air-fuel ratio is kept constant. (For example, Japanese Patent Publication No. 46-36947) Problems to be Solved by the Invention However, the relationship between the flame ion current and the air-fuel ratio is as shown in FIG. 6, where the air-fuel ratio P=Po and the ion current If is the peak value If = Ifo, and it is known that it is not a one-to-one function. In the conventional configuration as above, when If = If 1 , it is not possible to determine whether P = P 1 or P = P 2 . This has the problem that there is a possibility of making incorrect adjustments.
問題点を解決するための手段
上記問題点を解決するために本発明の燃焼制御
装置は、一対の電極で構成され燃焼火炎中のイオ
ン電流対空燃比特性が異なる箇所に挿入された主
フレームロツドセンサと、副フレームロツドセン
サと、前記各フレームロツドセンサの電極間に電
圧を印加する電源と、前記各フレームロツドセン
サと直列に接続された炎電流検出抵抗と、前記各
検出抵抗に流れる電流により空燃比を検出する空
燃比検出回路を有し、前記空燃比検出回路は主フ
レームロツドセンサの電流値を計測する電流値計
測回路と、副フレームロツドセンサの電流値と規
定の電流値を比較する比較回路を設け、前記空燃
比検出回路の出力により燃焼を制御する制御器を
有する構成としたものである。Means for Solving the Problems In order to solve the above problems, the combustion control device of the present invention has a main flame rod that is composed of a pair of electrodes and is inserted into a combustion flame at a location where the ionic current vs. air-fuel ratio characteristics are different. a sensor, an auxiliary flame rod sensor, a power source for applying a voltage between the electrodes of each of the flame rod sensors, a flame current detection resistor connected in series with each of the flame rod sensors, and a flame current detection resistor connected to each of the flame rod sensors in series; It has an air-fuel ratio detection circuit that detects the air-fuel ratio based on a flowing current, and the air-fuel ratio detection circuit includes a current value measurement circuit that measures the current value of the main frame rod sensor, and a current value measurement circuit that measures the current value of the sub frame rod sensor. A comparison circuit for comparing current values is provided, and a controller is provided for controlling combustion based on the output of the air-fuel ratio detection circuit.
作 用
本発明は上記した構成によつて、電流計測回路
の出力と比較回路の出力とにより誤りのない空燃
比を検出し、燃焼を制御するという作用を有す
る。Effects The present invention has the effect of detecting a correct air-fuel ratio based on the output of the current measurement circuit and the output of the comparison circuit and controlling combustion by using the above-described configuration.
実施例
以下、本発明の実施例を添付図面にもとづいて
説明する。なお、実施例の説明にあたつては第５
図と同一部分には便宜上同一符号を付した。第１
図において１はバーナで、このバーナ１から形成
される火炎に２本のフレームロツド２ａと２ｂが
挿入され、一方の電極をバーナ、他方の電極をフ
レームロツドとした主フレームロツドセンサ６ａ
と副フレームロツドセンサ６ｂを構成している。
３は電源でここでは直流電源を使用している。７
ａ，７ｂは炎電流検出用抵抗であり、８は空燃比
検出回路である。空燃比検出回路８は電流値計測
回路９と比較回路１０とで構成されている。主フ
レームロツドセンサ６ａと炎電流検出用抵抗７ａ
の接続点の電位は電流値計測回路９に、副フレー
ムロツドセンサ６ｂと炎電流検出用抵抗７ｂの接
続点の電位は比較回路１０に入力する。電流値計
測回路９は２個の演算増幅器１１，１２と抵抗１
３，１４で構成され、演算増幅器１１はボルテー
ジフオロア回路を構成し、主フレームロツドセン
サ６ａを流れる炎電流Ifaに比例した出力電力に
変換される。演算増幅器１２と抵抗１３，１４は
反転増幅回路を構成し、抵抗１５，１６，１７に
より分圧された基準電位に対して反転増幅してい
る。比較回路１０は演算増幅器１８と比較器１９
と抵抗２０，２１で構成され、演算増幅器１８は
ボルテージフオロア回路を構成し、副フレームロ
ツドセンサ６ｂを流れる炎電流Ifbに比例した出
力電圧に変換され、抵抗１５，１６，１７により
分圧された規定の電位と比較器１９により比較さ
れる。２２は制御器で停止装置２３と空燃比調整
装置２４より構成され、停止装置２３は比較回路
１０の出力信号に応じ機器の動作を停止し、空燃
比調整装置２４は電流値計測回路９の出力信号に
応じ空燃比を調整するものである。火炎中でフレ
ームロツドの挿入箇所によりイオン電流対空燃比
特性を変えることが可能であることは知られてお
り、主フレームロツドセンサ６ａと副フレームロ
ツドセンサ６ｂのイオン電流対空燃比特性を第２
図に示す。イオン電流Ifa，Ifbがピークとなる空
燃比はそれぞれＰ＝Pa，Ｐ＝Pbと違つた点にな
る。電流値計測回路９の出力電圧V9の特性は第
３図に示す様にイオン電流Ifaに比例したものと
なる。又、抵抗１５，１６，１７の値で比較器１
９の正側入力電圧を調整することにより比較回路
１０の出力電圧V10の特性は第３図に示す様にV9
がピーク値となる空燃比Ｐ＝PaでV10の出力が変
化する様に設定することが可能である。第３図で
空燃比Ｐ＝Pcで燃焼するように空燃比を調整し
て制御したいときは、空燃比調整装置２４には電
流値計測回路９の出力電圧V9が入力し、V9＝
V9cとなるように空燃比を調整する。又、空燃比
調整装置２４がV9＝V9cとなるように空燃比を調
整したために空燃比Ｐ＝Pdとなつてしまうこと
を防止するために停止装置２３には比較回路１０
の出力電圧V10が入力し、V10＝V10dのときには
機器の動作を停止する。以上により誤りのない空
燃比制御が可能になる。Embodiments Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. In addition, when explaining the example, please refer to the fifth
For convenience, the same parts as those in the figure are given the same reference numerals. 1st
In the figure, 1 is a burner, and two flame rods 2a and 2b are inserted into the flame formed from this burner 1, and the main flame rod sensor 6a has one electrode as a burner and the other electrode as a flame rod.
This constitutes the sub-frame rod sensor 6b.
3 is a power supply, and a DC power supply is used here. 7
Reference numerals a and 7b are resistances for detecting flame current, and reference numeral 8 is an air-fuel ratio detection circuit. The air-fuel ratio detection circuit 8 includes a current value measurement circuit 9 and a comparison circuit 10. Main flame rod sensor 6a and flame current detection resistor 7a
The potential at the connection point between the auxiliary flame rod sensor 6b and the flame current detection resistor 7b is input to the comparison circuit 10. The current value measurement circuit 9 includes two operational amplifiers 11 and 12 and a resistor 1.
The operational amplifier 11 constitutes a voltage follower circuit, and is converted into an output power proportional to the flame current Ifa flowing through the main flame rod sensor 6a. The operational amplifier 12 and the resistors 13 and 14 constitute an inverting amplifier circuit, and the reference potential divided by the resistors 15, 16, and 17 is inverted and amplified. The comparison circuit 10 includes an operational amplifier 18 and a comparator 19
The operational amplifier 18 constitutes a voltage follower circuit, and is converted into an output voltage proportional to the flame current Ifb flowing through the sub-flame rod sensor 6b. The comparator 19 compares the potential with the specified potential. Reference numeral 22 denotes a controller, which is composed of a stop device 23 and an air-fuel ratio adjusting device 24. The stopping device 23 stops the operation of the equipment according to the output signal of the comparator circuit 10, and the air-fuel ratio adjusting device 24 controls the output of the current value measuring circuit 9. The air-fuel ratio is adjusted according to the signal. It is known that the ion current vs. air-fuel ratio characteristics can be changed depending on the insertion point of the flame rod in a flame, and the ion current vs. air-fuel ratio characteristics of the main flame rod sensor 6a and the auxiliary flame rod sensor 6b can be changed as follows.
As shown in the figure. The air-fuel ratios at which the ion currents Ifa and Ifb reach their peaks are at different points, P=Pa and P=Pb, respectively. The characteristics of the output voltage V9 of the current value measuring circuit 9 are proportional to the ionic current Ifa, as shown in FIG. Also, the comparator 1 is
By adjusting the positive input voltage of the comparator circuit 10, the characteristics of the output voltage V10 of the comparator circuit 10 are changed to V9 as shown in FIG.
It is possible to set the output of V 10 to change at an air-fuel ratio P=Pa at which the peak value is reached. When it is desired to adjust and control the air-fuel ratio so that combustion occurs at the air-fuel ratio P=Pc in FIG. 3, the output voltage V 9 of the current value measurement circuit 9 is input to the air-fuel ratio adjustment device 24, and V 9 =
Adjust the air-fuel ratio so that V 9 c. In addition, in order to prevent the air-fuel ratio from becoming P=Pd because the air-fuel ratio adjusting device 24 has adjusted the air-fuel ratio so that V 9 =V 9 c, a comparison circuit 10 is provided in the stopping device 23.
When the output voltage V 10 of V 10 is input and V 10 = V 10 d, the device stops operating. The above enables error-free air-fuel ratio control.
次に本発明の別の実施例を第４図に示す。前記
実施例と相違する点は電源３に交流電源を使用し
ている点である。炎電流検出用抵抗７ａ，７ｂの
両端の電圧はコンデンサ２５ａ，２５ｂと抵抗２
６，２７でそれぞれなる積分回路で、整流作用に
より発生した直流分のみが積分され、積分回路の
出力電位が空燃比検出回路８に入力し、以下前記
実施例と同様の動作で誤りのない空燃比制御が可
能になる。以上の実施例では空燃比検出回路を演
算増幅器、比較器、抵抗を使用してアナログ的に
構成しているが、Ａ／Ｄ変換回路によりデイジタ
ル値に変換してマイクロコンピユータ等のプログ
ラムで構成してもよい。又、主フレームロツドセ
ンサが副フレームロツドセンサをパイロツトバー
ナ等別バーナの火炎に挿入しても実現可能であ
る。 Next, another embodiment of the present invention is shown in FIG. The difference from the previous embodiment is that an AC power source is used as the power source 3. The voltage across the flame current detection resistors 7a and 7b is determined by the capacitors 25a and 25b and the resistor 2.
Only the DC component generated by the rectification is integrated in the respective integrating circuits 6 and 27, and the output potential of the integrating circuit is input to the air-fuel ratio detection circuit 8. Fuel ratio control becomes possible. In the above embodiment, the air-fuel ratio detection circuit is configured in an analog manner using an operational amplifier, a comparator, and a resistor, but it can be converted into a digital value by an A/D conversion circuit and configured by a program on a microcomputer, etc. It's okay. It is also possible to implement the main flame rod sensor by inserting a sub flame rod sensor into the flame of a separate burner such as a pilot burner.
発明の効果
以上のように本発明の燃焼制御装置によれば次
の効果が得られる。Effects of the Invention As described above, the combustion control device of the present invention provides the following effects.
(1) 副フレームロツドセンサの電流値により空燃
比の範囲を絞り、主フレームロツドセンサの電
流値により空燃比を検出し燃焼制御を行なうの
で信頼性の高い制御を行なうことが可能であ
る。(1) The air-fuel ratio range is narrowed down based on the current value of the auxiliary flame rod sensor, and the air-fuel ratio is detected and combustion controlled using the current value of the main flame rod sensor, making it possible to perform highly reliable control. .
(2) 主フレームロツドセンサのイオン電流により
空燃比を検出し燃焼制御を行ない、副フレーム
ロツドセンサにより、酸欠、失火等燃焼異常を
検出する構成としているので機能を分割したこ
とにより、安全性の高い高度な燃焼制御を実現
できる。(2) The ion current of the main flame rod sensor detects the air-fuel ratio and performs combustion control, and the sub flame rod sensor detects combustion abnormalities such as oxygen deficiency and misfire, so by dividing the functions, It is possible to achieve highly safe and advanced combustion control.
第１図は本発明の一実施例を示す燃焼制御装置
の回路図、第２図はイオン電流の空燃比特性図、
第３図は空燃比検出回路出力電圧の空燃比特性
図、第４図は本発明の他の実施例を示す燃焼制御
装置の回路図、第５図は従来例の燃焼制御装置の
システム図、第６図はイオン電流の空燃比特性
図。
３……電源、６ａ……主フレームロツドセン
サ、６ｂ……副フレームロツドセンサ、７ａ，７
ｂ……炎電流検出抵抗、８……空燃比検出回路、
９……電流値計測回路、１０……比較回路、２２
……制御器。
FIG. 1 is a circuit diagram of a combustion control device showing an embodiment of the present invention, FIG. 2 is an air-fuel ratio characteristic diagram of ion current,
FIG. 3 is an air-fuel ratio characteristic diagram of the air-fuel ratio detection circuit output voltage, FIG. 4 is a circuit diagram of a combustion control device showing another embodiment of the present invention, and FIG. 5 is a system diagram of a conventional combustion control device. Figure 6 is an air-fuel ratio characteristic diagram of ion current. 3...Power supply, 6a...Main frame rod sensor, 6b...Sub frame rod sensor, 7a, 7
b...Flame current detection resistor, 8...Air-fuel ratio detection circuit,
9... Current value measurement circuit, 10... Comparison circuit, 22
...Controller.
Claims (1)
流対空燃比特性が異なる箇所に挿入された主フレ
ームロツドセンサと、副フレームロツドセンサ
と、前記各フレームロツドセンサの電極間に電圧
を印加する電源と、前記各フレームロツドセンサ
と直列に接続された炎電流検出抵抗と、前記各検
出抵抗に流れる電流により空燃比を検出する空燃
比検出回路を有し、前記空燃比検出回路は主フレ
ームロツドセンサの電流値を計測する電流値計測
回路と、副フレームロツドセンサの電流値と規定
の電流値を比較する比較回路を設け、前記空燃比
検出回路の出力により燃焼を制御する制御器を有
する燃焼制御装置。 ２ 制御器は比較回路の出力により機器の動作を
停止する停止装置と、電流計測回路の出力に応じ
空燃比を調整する空燃比調整装置を有する構成の
特許請求の範囲第１項記載の燃焼制御装置。[Scope of Claims] 1. A main flame rod sensor, a sub flame rod sensor, and a sub flame rod sensor, each of which is composed of a pair of electrodes and inserted at locations with different ionic current vs. air-fuel ratio characteristics in a combustion flame. The flame rod sensor has a power source for applying a voltage between the electrodes, a flame current detection resistor connected in series with each of the flame rod sensors, and an air-fuel ratio detection circuit that detects the air-fuel ratio based on the current flowing through each of the detection resistors. The air-fuel ratio detection circuit includes a current value measurement circuit that measures the current value of the main frame rod sensor, and a comparison circuit that compares the current value of the auxiliary frame rod sensor with a specified current value, and the output of the air-fuel ratio detection circuit A combustion control device that has a controller that controls combustion. 2. Combustion control according to claim 1, wherein the controller has a stop device that stops the operation of the equipment based on the output of the comparison circuit, and an air-fuel ratio adjustment device that adjusts the air-fuel ratio according to the output of the current measurement circuit. Device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60146002A JPS629118A (en) | 1985-07-03 | 1985-07-03 | Combustion control device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60146002A JPS629118A (en) | 1985-07-03 | 1985-07-03 | Combustion control device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS629118A JPS629118A (en) | 1987-01-17 |
| JPH0421094B2 true JPH0421094B2 (en) | 1992-04-08 |
Family
ID=15397877
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60146002A Granted JPS629118A (en) | 1985-07-03 | 1985-07-03 | Combustion control device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS629118A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1996033373A1 (en) * | 1995-04-19 | 1996-10-24 | Bowin Technology Pty. Limited | Heating appliance |
| FR2805029B1 (en) * | 2000-02-15 | 2002-07-19 | Brandt Cooking | GAS BURNER CONTROL DEVICE |
| ITAN20020038A1 (en) * | 2002-08-05 | 2004-02-06 | Merloni Termosanitari Spa Ora Ariston Thermo Spa | LAMBDA VIRTUAL SENSOR COMBUSTION CONTROL SYSTEM. |
-
1985
- 1985-07-03 JP JP60146002A patent/JPS629118A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS629118A (en) | 1987-01-17 |
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