JPH0610540B2 - Combustion control device - Google Patents
Combustion control deviceInfo
- Publication number
- JPH0610540B2 JPH0610540B2 JP60298424A JP29842485A JPH0610540B2 JP H0610540 B2 JPH0610540 B2 JP H0610540B2 JP 60298424 A JP60298424 A JP 60298424A JP 29842485 A JP29842485 A JP 29842485A JP H0610540 B2 JPH0610540 B2 JP H0610540B2
- Authority
- JP
- Japan
- Prior art keywords
- gas
- control valve
- fan motor
- proportional control
- burner
- 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 - Fee Related
Links
- 238000002485 combustion reaction Methods 0.000 title claims description 24
- 239000007789 gas Substances 0.000 description 39
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 12
- 230000007423 decrease Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 2
- 238000011144 upstream manufacturing Methods 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
Classifications
-
- 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
- F23N1/022—Regulating fuel supply conjointly with air supply using electronic means
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23N—REGULATING OR CONTROLLING COMBUSTION
- F23N2227/00—Ignition or checking
- F23N2227/20—Calibrating devices
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23N—REGULATING OR CONTROLLING COMBUSTION
- F23N2233/00—Ventilators
- F23N2233/06—Ventilators at the air intake
- F23N2233/08—Ventilators at the air intake with variable speed
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23N—REGULATING OR CONTROLLING COMBUSTION
- F23N2235/00—Valves, nozzles or pumps
- F23N2235/12—Fuel valves
- F23N2235/16—Fuel valves variable flow or proportional valves
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Regulation And Control Of Combustion (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は異なる種類のガスを使用する場合にも同一の電
磁式比例弁を用いることができるようにしたガス燃焼器
の燃焼制御装置に関する。Description: TECHNICAL FIELD The present invention relates to a combustion control device for a gas combustor in which the same electromagnetic proportional valve can be used even when different types of gas are used.
（従来の技術） 従来のこの種装置として、バーナの負荷温度と設定温度
との偏差に応じて電磁式比例制御弁の通電電流の大きさ
を制御すると共に、該通電電流をファンモータの駆動制
御回路に分岐し、一定の増加率で該通電電流の大きさに
比例してファンの風量を制御し、ガス量の増減に応じて
風量を増減するようにしたものが知られている。(Prior Art) As a conventional device of this type, the magnitude of the energizing current of the electromagnetic proportional control valve is controlled according to the deviation between the load temperature of the burner and the set temperature, and the energizing current is controlled to drive the fan motor. It is known to branch into a circuit and control the air volume of the fan in proportion to the magnitude of the energizing current at a constant increase rate to increase or decrease the air volume according to the increase or decrease of the gas volume.
ところで、現在使用されているガスは複数種類あり、こ
れらガス種毎に単位体積当たりの発熱量が異なる。上記
従来の湯沸器において、例えば低発熱量のガスである４
Ｃから高発熱量のガスである１３Ａに切り替える場合
に、湯沸器の出湯能力を一定にするためには比例制御弁
の通電電流の制御範囲を変更し比例制御弁の開度を４Ｃ
の場合より絞り込み、１３Ａの流量を全体に減少させな
ければならない。但し、このように比例制御弁の開度を
絞り込むとノズルにおける噴出圧力が低下するが、ノズ
ルからのガスの噴出量は噴出圧力の1/2乗に比例するこ
とが知られており、噴出出力が低い程ガス圧の変動が噴
出量に対して大きく影響する。高発熱量のガスは低発熱
量のガスよりも噴出量の変動がバーナにおける総発熱量
（燃焼量）に対して大きく影響するので、実際には４Ｃ
の場合より１３Ａの噴出圧力を高めて噴出量を安定さ
せ、その代わり４Ｃの場合より小径のノズルを用いて噴
出量自体は４Ｃの場合より少なくなるように調整してい
る。このように、ガス種を変更する場合にはガス種に応
じたノズルに変換する場合と交換しない場合とで通電電
流の制御範囲を広げるか狭めるかの違いはあるが、いず
れの場合にもガス種切替に伴って比例制御弁への通電電
流の制御範囲を変更する必要がある。By the way, there are a plurality of gases currently used, and the calorific value per unit volume is different for each of these gas species. In the above-mentioned conventional water heater, for example, a gas having a low heating value 4
When switching from C to 13A, which is a gas with a high calorific value, in order to make the hot water discharge capacity of the water heater constant, the control range of the energizing current of the proportional control valve is changed and the opening of the proportional control valve is changed to 4C.
It is necessary to reduce the flow rate of 13A as a whole by narrowing down the flow rate of 13A. However, if the opening of the proportional control valve is narrowed down in this way, the ejection pressure at the nozzle decreases, but it is known that the amount of gas ejected from the nozzle is proportional to the 1/2 power of the ejection pressure. The lower the value, the greater the fluctuation of the gas pressure has on the ejection amount. In the case of a gas with a high calorific value, the fluctuation of the ejection amount has a greater effect on the total calorific value (combustion amount) in the burner than with a gas with a low calorific value.
The jet pressure of 13 A is increased to stabilize the jet amount than in the case of, and instead, the jet amount itself is adjusted to be smaller than that of 4 C by using a nozzle having a smaller diameter than that of 4 C. In this way, when changing the gas type, there is a difference in whether the control range of the energizing current is widened or narrowed depending on whether the nozzle is changed according to the gas type or not. It is necessary to change the control range of the energizing current to the proportional control valve according to the species switching.
（発明が解決しようとする問題点） 一方、このようにガス種に応じて噴出量が増減されても
燃焼量が一定である限り燃焼に要する酸素量は変わらな
いが、上記従来の湯沸器では比例制御弁への通電電流に
比例するようにファンモータの回転数を制御しているの
で、比例制御弁への通電電流の範囲が変更されればそれ
に伴ってファンモータの回転数も変更され、燃焼量に対
して適正な燃焼用空気を供給できず不良燃焼を生じると
いう不具合が生じる。(Problems to be Solved by the Invention) On the other hand, even if the ejection amount is increased or decreased according to the gas type, the oxygen amount required for combustion does not change as long as the combustion amount is constant. Since the rotation speed of the fan motor is controlled so as to be proportional to the current supplied to the proportional control valve, if the range of the current supplied to the proportional control valve is changed, the rotation speed of the fan motor will be changed accordingly. However, there is a problem that an appropriate combustion air cannot be supplied with respect to the amount of combustion, resulting in defective combustion.
尚、このような場合に燃焼用空気の供給量を手動操作に
より調節するようにしたものが実開昭５８−１０７４４
７号公報により知られているが、比例制御弁に対する切
換操作の他に空気の供給量に対する調節操作も行わなけ
ればならず、この空気の供給量に対する手動操作を忘れ
た場合には不完全燃焼となり安全性に劣る。Incidentally, in such a case, the one in which the supply amount of combustion air is adjusted by a manual operation is the actual open-circuit sho 58-10744.
As is known from Japanese Patent Laid-Open No. 7-75, in addition to the switching operation for the proportional control valve, the adjustment operation for the air supply amount must be performed, and if the manual operation for the air supply amount is forgotten, incomplete combustion occurs. And is inferior in safety.
そこで本発明は上記問題点に鑑み、ガス種の変更に伴っ
て比例制御弁の通電電流の制御範囲を変更しても燃焼量
と燃焼用空気の供給量との関係は一定に維持して常に正
常燃焼をし得る燃焼制御装置を提供することを目的とす
る。Therefore, in view of the above problems, the present invention maintains a constant relationship between the combustion amount and the supply amount of combustion air even when the control range of the energizing current of the proportional control valve is changed with the change of the gas type. An object of the present invention is to provide a combustion control device capable of performing normal combustion.
（問題点を解決するための手段） 本発明は上記目的を達成するために、バーナへのガス供
給路に介設する電磁式比例制御弁と、該バーナに空気を
供給するファンモータとを備え、該ファンモータの回転
数を該比例制御弁の通電電流の大きさに応じて所定の増
加率で比例変化させるようにしたものにおいて、ガスの
種類に応じて該比例制御弁の通電電流の制御範囲を変化
させる切換手段と、切換手段の作動に連動して上記増加
率をガスの種類毎に予め設定された値に変化させガスの
種類のいかんにかかわらずファンモータの回転数の制御
範囲を一定にする制御手段とを設けたことを特徴とす
る。(Means for Solving Problems) In order to achieve the above object, the present invention includes an electromagnetic proportional control valve provided in a gas supply path to a burner and a fan motor for supplying air to the burner. Controlling the energizing current of the proportional control valve according to the type of gas, in which the number of revolutions of the fan motor is proportionally changed at a predetermined increase rate according to the magnitude of the energizing current of the proportional control valve. The switching means for changing the range and the increase rate in conjunction with the operation of the switching means are changed to a preset value for each type of gas to change the control range of the fan motor speed regardless of the type of gas. It is characterized in that a control means for making it constant is provided.
（作用） ガス種に応じて上記通電電流の制御範囲が変更される
と、これに連動して通電電流の制御範囲の変更の影響を
キャンセルするように上記増加率が自動的に変化する。
そのため、通電電流の制御範囲を変更した影響がファン
モータの回転数に影響せず、燃焼量と燃焼用空気の供給
量との関係は一定に維持される。(Operation) When the control range of the energization current is changed according to the gas type, the increase rate is automatically changed in association with this so as to cancel the influence of the change of the control range of the energization current.
Therefore, the influence of changing the control range of the energizing current does not affect the rotation speed of the fan motor, and the relationship between the combustion amount and the supply amount of combustion air is maintained constant.
（実施例） 次に本発明をガス給湯器に適用した場合の実施例を図面
に基づいて説明する。(Example) Next, an example when the present invention is applied to a gas water heater will be described with reference to the drawings.
第１図において、(1)は下部に通気孔(2)を備え、上部に
排気筒(3)を備えるガス給湯器本体であって、該本体(1)
内には、中間部に熱交換器(4)とこれを加熱する表面燃
焼式バーナ(5)とを備え、下部に該バーナ(5)へ燃焼用空
気を供給する直流のファンモータ(6)を備え、上部に前
記排気筒(3)に連なる排気口(7)を備える燃焼筐(8)を収
容し、該熱交換器(4)の上流側の給水管(9)から送られて
くる水を該熱交換器(4)内で温め、該熱交換器(4)の下流
側の出湯管(10)から湯が得られるようにすると共に燃焼
排気を排気筒(3)を介して外部へ放出するようにした。In FIG. 1, (1) is a gas water heater main body having a vent hole (2) in a lower portion and an exhaust pipe (3) in an upper portion, the main body (1)
Inside, a heat exchanger (4) and a surface combustion burner (5) for heating the heat exchanger (4) are provided in the middle part, and a DC fan motor (6) for supplying combustion air to the burner (5) is provided in the lower part. And a combustion casing (8) having an exhaust port (7) connected to the exhaust pipe (3) in the upper part is accommodated, and is sent from the water supply pipe (9) on the upstream side of the heat exchanger (4). The water is warmed in the heat exchanger (4) so that hot water can be obtained from the hot water outlet pipe (10) on the downstream side of the heat exchanger (4), and the combustion exhaust gas is externally supplied through the exhaust stack (3). To be released to.
図中、(11)はバーナ(5)に連なるガス供給路を示し、該
ガス供給路(11)には上流側の電磁式開閉弁(12)と下流側
の電磁式比例制御弁(13)とを介設した。In the figure, (11) shows a gas supply path connected to the burner (5), in the gas supply path (11) upstream solenoid valve (12) and downstream solenoid proportional control valve (13) And installed.
該バーナ(5)へのガス供給量の増減制御は第２図に示す
ように制御回路(14)内の従来と同様の構成を有する比例
制御回路(15)で行なうもので、前記出湯管(10)内の感温
素子(16)によって検出された実際の出湯温度と該比例制
御回路(15)内の設定温度との偏差に応じた信号により、
電磁式開閉弁(12)のコイルを通電若しくは通電停止させ
て開弁若しくは閉弁させると共に電磁式比例制御弁(13)
のコイルに流れる電流を例えばＬＰＧを使用する場合に
は第３図のＡ線に示すように略15乃至230mAの範囲で変
化させて開度を調節して行なう。As shown in FIG. 2, the increase / decrease control of the gas supply amount to the burner (5) is performed by a proportional control circuit (15) in the control circuit (14) having the same structure as the conventional one. By the signal according to the deviation between the actual hot water temperature detected by the temperature sensing element (16) in 10) and the set temperature in the proportional control circuit (15),
Energize or stop energizing the coil of the electromagnetic on-off valve (12) to open or close it, and also the electromagnetic proportional control valve (13)
When the LPG is used, for example, the current flowing in the coil is changed in the range of approximately 15 to 230 mA as shown by the line A in FIG. 3 to adjust the opening.
また、該バーナ(5)への空気供給量の増減制御は制御回
路(14)内の風量制御回路(17)で行なうもので、前記比例
制御回路(15)から電磁式比例制御弁(13)のコイルに送ら
れる電流と同じ電流を入力してこれに所定の増加率を乗
じて略12乃至37Vの間の電圧に変換し、その電圧を前記
ファンモータ(6)に印加して回転数を略500乃至5000rpm
の範囲で変化させて行なう。Further, the increase / decrease control of the air supply amount to the burner (5) is performed by the air flow control circuit (17) in the control circuit (14), and the proportional control circuit (15) causes an electromagnetic proportional control valve (13). The same current as the current sent to the coil is input, this is multiplied by a predetermined increase rate and converted into a voltage between approximately 12 to 37 V, and the voltage is applied to the fan motor (6) to change the rotation speed. About 500 to 5000 rpm
Change within the range of.
第２図中、(18)はファンモータ(6)のフィードバック回
路を示す。In FIG. 2, (18) shows a feedback circuit of the fan motor (6).
上記のようなガス供給量と空気供給量の制御において、
バーナ(5)に供給するガスの種類を例えば第３図に示す
ようにLPGから4Cに変えたときは、制御回路(14)内の切
換手段たるガス種切替回路(19)により比例制御回路(15)
内の調整抵抗(20)の値を変え、基準となる接続点の電位
を変えて、電磁式比例制御弁(13)のコイルに流す電流の
制御範囲を15乃至230mAから15乃至45mAに変化させると
共に、制御回路(14)内の制御手段たる比率変更回路(21)
により風量制御回路(17)内の図示しない切換スイッチを
切換え、基準となる接続点の電位を変えて、該コイルに
流す電流に対するファンモータ(6)の回転数の増加率を
増やして燃焼用空気の供給量には通電電流の制御範囲の
変更による影響が及ばないようにした。これにより、ガ
ス種を変えてもバーナ(5)の燃焼量の制御範囲ひいては
ガス給湯器により供給される湯の温度の制御範囲が変わ
らないようにした。In controlling the gas supply amount and air supply amount as described above,
When the type of gas supplied to the burner (5) is changed from LPG to 4C as shown in FIG. 3, for example, the proportional control circuit (19) is switched by the gas type switching circuit (19) which is the switching means in the control circuit (14). 15)
By changing the value of the adjusting resistor (20) inside, changing the potential of the reference connection point, the control range of the current flowing in the coil of the electromagnetic proportional control valve (13) is changed from 15 to 230mA to 15 to 45mA. Together with, the ratio changing circuit (21) which is the control means in the control circuit (14)
To change the changeover switch (not shown) in the air volume control circuit (17) to change the potential of the reference connection point to increase the rate of increase of the rotation speed of the fan motor (6) with respect to the current flowing in the coil, thereby increasing the combustion air. The supply amount of is not affected by changing the control range of the energizing current. As a result, even if the gas type is changed, the control range of the combustion amount of the burner (5), that is, the control range of the temperature of the hot water supplied by the gas water heater does not change.
尚、図示のものでは空気供給量がガス供給量に対して過
剰にならないようにファンモータ(6)の電圧の上限を37V
におさえた。In the case of the one shown in the figure, the upper limit of the voltage of the fan motor (6) is 37 V so that the air supply amount does not become excessive with respect to the gas supply amount.
It was suppressed.
尚、電磁式比例制御弁(13)の通電電流とファンモータ
(6)の回転数との関係を決定する際、低カロリーガスを
基準とすると調整が容易である。The energizing current of the electromagnetic proportional control valve (13) and the fan motor
When determining the relationship with the rotation speed of (6), it is easy to adjust if low-calorie gas is used as a reference.
（発明の効果） このように本発明によるときは、ガスの種類に応じて電
磁式比例制御弁の通電電流の制御範囲を変化させる切換
手段と、該比例制御弁の通電電流に対するファンモータ
の回転数の増加率を変化させる制御手段とを設けて、ガ
ス種に係わりなくバーナの燃焼量に見合った量の空気を
自動的に供給できるようにしたので、ガス種の変更に際
して比例制御弁に対する切換操作の他に空気供給量を手
動操作にて調節するようにした上記従来装置の場合にの
ように、該空気供給量に対する調節を忘れるおそれがな
く、したがって、空気供給量が不足してバーナの炎がリ
フトしたり、空気供給量が過剰となってバーナが爆発着
火したりする虞れがなくなる効果を有する。(Effect of the invention) As described above, according to the present invention, the switching means for changing the control range of the energization current of the electromagnetic proportional control valve according to the type of gas, and the rotation of the fan motor with respect to the energization current of the proportional control valve. By providing a control means for changing the rate of increase in the number, it is possible to automatically supply an amount of air commensurate with the combustion amount of the burner regardless of the gas type, so switching to the proportional control valve when changing the gas type As in the case of the above-mentioned conventional device in which the air supply amount is manually adjusted in addition to the operation, there is no risk of forgetting to adjust the air supply amount. This has the effect of eliminating the risk of flame lifting and excessive burnout of the burner due to excessive air supply.
第１図は本発明の実施の一例を示す説明線図、第２図は
その要部を示すブロック線図、第３図はガス種を変化さ
せたときの比例制御弁の通電電流とファンモータの回転
数との関係を示す特性線図である。 (5)……バーナ、(6)……ファンモータ (11)……ガス供給路、(13)……電磁式比例制御弁 (19)……ガス種切替回路（切換手段） (21)……比率変更回路（制御手段）FIG. 1 is an explanatory diagram showing an example of an embodiment of the present invention, FIG. 2 is a block diagram showing the main part thereof, and FIG. 3 is a current flowing through a proportional control valve and a fan motor when a gas type is changed. FIG. 4 is a characteristic diagram showing the relationship with the rotation speed of (5) ...... Burner, (6) ...... Fan motor (11) ...... Gas supply path, (13) ...... Electromagnetic proportional control valve (19) ...... Gas type switching circuit (switching means) (21) ... ... Ratio changing circuit (control means)
Claims (1)
例制御弁と、該バーナに空気を供給するファンモータと
を備え、該ファンモータの回転数を該比例制御弁の通電
電流の大きさに応じて所定の増加率で比例変化させるよ
うにしたものにおいて、ガスの種類に応じて該比例制御
弁の通電電流の制御範囲を変化させる切換手段と、切換
手段の作動に連動して上記増加率をガスの種類毎に予め
設定された値に変化させガスの種類のいかんにかかわら
ずファンモータの回転数の制御範囲を一定にする制御手
段とを設けたことを特徴とする燃焼制御装置。1. An electromagnetic proportional control valve provided in a gas supply path to a burner, and a fan motor for supplying air to the burner, wherein the rotation speed of the fan motor is controlled by the energizing current of the proportional control valve. In a configuration in which a proportional change is made at a predetermined increase rate according to the size, switching means for changing the control range of the energizing current of the proportional control valve according to the type of gas, and interlocking with the operation of the switching means Combustion control, characterized in that the increasing rate is changed to a preset value for each type of gas, and control means is provided for making the control range of the rotation speed of the fan motor constant regardless of the type of gas. apparatus.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60298424A JPH0610540B2 (en) | 1985-12-28 | 1985-12-28 | Combustion control device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60298424A JPH0610540B2 (en) | 1985-12-28 | 1985-12-28 | Combustion control device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62158918A JPS62158918A (en) | 1987-07-14 |
| JPH0610540B2 true JPH0610540B2 (en) | 1994-02-09 |
Family
ID=17859526
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60298424A Expired - Fee Related JPH0610540B2 (en) | 1985-12-28 | 1985-12-28 | Combustion control device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0610540B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0289914A (en) * | 1988-09-27 | 1990-03-29 | Rinnai Corp | Control device for forced draft type combustion device |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5183236A (en) * | 1975-01-18 | 1976-07-21 | Matsushita Electric Industrial Co Ltd | Nenshoseigyosochi |
| JPS59104020A (en) * | 1982-12-07 | 1984-06-15 | Matsushita Electric Ind Co Ltd | Gas type conversion device |
-
1985
- 1985-12-28 JP JP60298424A patent/JPH0610540B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62158918A (en) | 1987-07-14 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |