JP2002295829A - Combustion equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive compact combustion equipment with a simplified construction that has both of firing and flame detection functions. SOLUTION: A combustion apparatus incorporates a firing circuit 24 and a flame detection circuit 25 on an electrode rod 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion apparatus applied to heating equipment such as a heating furnace and a heat treatment furnace.

[0002]

2. Description of the Related Art Conventionally, a combustion apparatus applied to a heating facility is:
As shown in FIG. 11, a fuel supply unit 2 provided on the upstream side with a flange 1 interposed therebetween, and a combustion gas generation unit 3 provided on the downstream side
It is configured to have:

The fuel supply unit 2 includes a main fuel nozzle 6 at a tip end on the side facing the combustion gas generation unit 3 in a tubular fuel supply casing 5 arranged at the center of a box-shaped air chamber 4. And a concentrically formed air passage 8 on the outside thereof.

The fuel supply section 2 is disposed concentrically outside the fuel supply casing 5, has an air guide path 10 provided with a swirler 9 on the inlet side, and has an air chamber 4 formed in a box shape. Air port 11 for guiding air from outside
It has.

On the other hand, a combustion gas generator 3 includes a flame detector 14 extending from the combustion casing 12 toward the main fuel nozzle 6 of the combustion chamber 13, and a pilot fuel nozzle arranged to face the flame detector 14. 15 is provided.

In the combustion device having such a configuration, the fuel supplied from the fuel guide pipe 7 is guided to the main fuel nozzle 6 together with the air from the air passage 8 and from the air port 11 of the air chamber 4. The swirler 9 mixes with the swirling air supplied through the air guide path 10 and burns in the combustion chamber 13 with the fire of the pilot fuel nozzle 15,
Generates combustion gas.

After the fuel from the main fuel nozzle 6 is ignited, the fuel supply from the pilot fuel nozzle 15 is normally stopped, and the main fuel nozzle 6 is singly burned.

At this time, the flame detector 14 detects the flame. When the flame has been misfired, an alarm or the like is transmitted. As the flame detector 14, at least one of an optical system such as an ultravision, a frame rod for detecting an ion current in the flame, and the like is used.

[0009]

The conventional combustion apparatus requires a pilot fuel nozzle 15 and a flame detector 14 because of the necessity of securing the type of fire in the main fuel nozzle 6 and monitoring the presence or absence of flame misfire. And had

However, recently, as the combustion apparatus has become more compact and smaller, the pilot fuel nozzle 1
5 and the flame detector 14 are limited in securing space. In particular, when using the pilot fuel nozzle 15 as a fire source for igniting the main fuel nozzle 6, a compact pilot fuel nozzle 15 that fits in a narrow space is required. Further, a simple and low-cost combustion device is desired.

The present invention has been made in light of such background art, and has as its object to provide a compact, low-cost combustion apparatus which has both ignition and flame detection, and has a simple structure. I do.

[0012]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have made intensive studies and as a result, extended the electrode rod connected to the ignition plug, and extended the tip of the extended electrode rod. By arranging the electrode rod close to the combustion chamber, the inventors came to invent that one electrode rod can be used for both fire type (ignition) and flame detection.

That is, in the combustion apparatus according to the present invention, as described in claim 1, the electrode rod of the ignition plug is housed in the casing, and the spark of the electrode rod burns a mixture of fuel and air. In the apparatus, an ignition circuit and a flame detection circuit are connected to the electrode rod.

[0014] The combustion apparatus according to the present invention is characterized by claim 2.
As described in the above, in the combustion device that accommodates the electrode rod of the ignition plug in the casing and burns a mixture of fuel and air with the spark of the electrode rod, the ignition circuit and the flame detection circuit connected to the electrode rod A switching relay and a switch, wherein when the switch is turned off, the switching relay is switched to the flame detection circuit side, and when the switch is turned on, the switching relay is switched to the ignition circuit side.

[0015] The combustion apparatus according to the present invention is characterized by claim 3.
As described above, the switching relay is a vacuum relay.

Further, the combustion apparatus according to the present invention is characterized in claim 4.
As described in the above, the ignition circuit includes a timer circuit in which the switching relay operates on the ignition circuit side with a time delay.

Further, the combustion apparatus according to the present invention is characterized in that
As described above, the timer circuit is provided between the transformer of the ignition circuit and the power supply.

Further, the combustion apparatus according to the present invention is characterized in claim 6.
As described in the above, the flame detection circuit includes a timer circuit in which a switching relay operates on the flame detection circuit side with a time delay.

Further, the combustion apparatus according to the present invention is characterized by claim 7.
As described above, the timer circuit is provided between the flame detector of the flame detection circuit and the switching relay.

Further, the combustion apparatus according to the present invention is characterized in claim 8.
As described in the above, in the combustion device that accommodates the electrode rod of the ignition plug in the casing and burns a mixture of fuel and air with the spark of the electrode rod, the ignition circuit and the flame detection circuit connected to the electrode rod , A switching relay and a switch, wherein the switch is turned from ON to OFF,
A flame detector for providing a close signal to a solenoid valve provided on the fuel port side of the casing when the misfire of the air-fuel mixture is detected is incorporated in the flame detection circuit.

[0021] The combustion apparatus according to the present invention is characterized by claim 9.
As described in (1), the electrode rod has a configuration in which the tip is formed in a bent portion and the distance to the inner wall surface of the casing to be accommodated is shortened.

Further, the combustion apparatus according to the present invention is characterized in claim 1.
As described in No. 0, the casing is provided with a projecting piece on its inner wall surface to reduce the distance from the electrode rod.

[0023] The combustion apparatus according to the present invention is characterized in claim 1.
As described in 1, in a combustion apparatus provided with a main fuel nozzle on the head side of the combustion chamber, and a flame detector and a pilot fuel nozzle in the combustion chamber in a direction intersecting the main fuel nozzle, The fuel nozzle has a passage along the axial direction of the nozzle.

[0024] The combustion apparatus according to the present invention is characterized in claim 1.
As described in 2, the combustion apparatus includes a main fuel nozzle on the head side of the combustion chamber, and a flame detector and a pilot fuel nozzle in the combustion chamber in a direction intersecting the main fuel nozzle. An electrode rod is incorporated in the fuel nozzle, and the electrode rod is also used as a flame detector for the main fuel nozzle.

[0025] The combustion apparatus according to the present invention is characterized in claim 1.
As described in 3, in a combustion device in which an electrode rod of an ignition plug is housed in a casing and a mixture of fuel and air is burned by a spark of the electrode rod, an ignition circuit and a flame detection circuit are provided on the electrode rod. A DC / AC converter is provided in the ignition circuit and the flame detection circuit in addition to the connection.

[0026]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a combustion apparatus according to an embodiment of the present invention.

FIG. 1 is a conceptual diagram showing a first embodiment of a combustion apparatus according to the present invention.

The combustion device according to the present embodiment is capable of performing both ignition of fuel and detection of flame, and has an integral structure in which an ignition plug 16 and a burner 17 are combined.

The burner section 17 is provided with a fuel port 19 and an air port 20 in a cylindrical casing 18 and a premixed gas passage 21.
And an electrode rod 23 disposed at the center of the premixed gas passage 21, having one end connected to the terminal 22 and the other end extending long toward the combustion chamber 32.

On the other hand, the ignition plug 16 includes an ignition circuit 24 and a flame detection circuit 25.

The ignition circuit 24 includes a switch 26, a transformer 27, and a power supply 28. The flame detection circuit 25
Is provided with a switch 29, a flame detector 30, and a power supply 31. The flame detector 30 and the transformer 27 of the ignition circuit 24 are electrically connected to the terminal 22 of the electrode bar 23.

In the combustion apparatus having such a configuration, fuel is supplied to the fuel port 19 of the casing 18, air is supplied to the air port 20, and the premixed gas passage 2 is provided.
The premixed gas merged in 1 flows toward the combustion chamber 32. At that time, when the switch 26 is turned on, the ignition circuit 24 causes a high voltage to flow from the transformer 27 to the electrode rod 23 via the ignition plug 26, thereby generating a spark from the electrode rod 23, igniting the premixed gas, and generating a flame. Generate.

When a flame is generated, the switch 26 of the ignition circuit 24 is turned off, and the switch 29 of the flame detection circuit 25 is turned off.
Is turned on. Then, the flame detector 30 of the flame detection circuit 25 detects the ion current via the electrode rod 23 and detects the flame. At this time, if a fire has occurred, the electrode rod 23 is detected as having lost light because the electrode rod 23 cannot detect the flame.

As described above, in the present embodiment, the casing 1
8, the ignition circuit 24 and the flame detection circuit 25 are incorporated in one electrode rod 23, and different functions of ignition of the premixed gas and detection of the flame are performed. Since the configuration is such that one electrode rod 23 can also be used, a simple and compact structure and a low-cost combustion device can be realized.

FIG. 2 is a conceptual diagram showing a second embodiment of the combustion apparatus according to the present invention. The same parts as those of the first embodiment are denoted by the same reference numerals.

The combustion device according to the present embodiment has an ignition circuit 2
A switching relay 33 is provided so that the circuit 4 and the flame detection circuit 25 can be switched freely. The other components are the same as the components of the first embodiment, and the description is omitted.

Now, the electrode rod 23 is sparked and the combustion chamber 3
When igniting the premixed gas of No. 2, switch 34 is turned on.
Then, the switching relay 33 moves the contact 35 from the contact A to the contact B. When the switch 34 is turned off, the switching relay 33 returns the contact 35 from the contact B to the contact A, and causes the flame detector 30 to detect the flame of the premixed gas in the combustion chamber 32 via the electrode rod 23. In addition, the switching relay 33 is configured such that a high current flows when the premixed gas is ignited, and the flame detector 30 considers breakage due to the induced current, etc.
For example, a high current vacuum relay is used.

As described above, in the present embodiment, the ignition circuit 24
And the flame detection circuit 25 can be switched freely and the switching relay 33 is provided, so that the switching operation between the ignition of the premixed gas and the flame detection can be easily performed.

FIG. 3 is a conceptual diagram showing a third embodiment of the combustion apparatus according to the present invention. The same components as those of the first embodiment are denoted by the same reference numerals.

The combustion apparatus according to the present embodiment includes a combustion chamber 32
When the premixed gas is ignited by turning on the switch 34,
The ignition circuit 2 prevents the induced current from flowing from the transformer 27 of the ignition circuit 24 to the flame detection circuit 25 transiently.
4 is provided with a timer circuit 36 for delaying the flow of current to 4.

As described above, in the present embodiment, the ignition circuit 24
Since the current flowing through the ignition circuit 24 is transiently delayed by the timer circuit 36 when the premixed gas in the combustion chamber 32 is ignited, a transiently induced current flows through the flame detection circuit 25. Therefore, the flame detection circuit 25 can be reliably protected.

In the present embodiment, when switching from the flame detection circuit 25 to the ignition circuit 24, a timer circuit 36 is provided in the ignition circuit 24 to delay the ignition of the premixed gas in the combustion chamber 32, and the induced current transiently changes. Although it is prevented from flowing to the flame detection circuit 25, the present invention is not limited to this example. For example, as shown in FIG.
When switching from the ignition circuit 24 to the flame detection circuit 25, the flow of current may be transiently delayed to protect the flame detection circuit 25 from induced current.

FIG. 5 is a conceptual diagram showing a fifth embodiment of the combustion apparatus according to the present invention. The same components as those of the first embodiment are denoted by the same reference numerals.

The combustion device according to this embodiment has a fuel port 19
An electromagnetic valve 41 is provided on the inlet side of the valve. When the contact 35 of the switching relay 33 is turned on to the contact A and the flame detector 30 of the flame detection circuit 25 detects misfire of the combustion chamber 32, the detection signal E The electromagnetic valve 41 is provided to the valve 41 to close the valve.

As described above, in the present embodiment, the solenoid valve 41 is provided on the inlet side of the fuel port 19, the flame detector 30 detects a misfire, and a detection signal is given to the solenoid valve 41 to close the valve. The unit 17 can perform safe and stable operation.

FIG. 6 is a conceptual diagram showing a sixth embodiment of the combustion apparatus according to the present invention. The same components as those of the first embodiment are denoted by the same reference numerals.

In the combustion device according to the present embodiment, the tip of the electrode rod 23 housed in the casing 18 is formed in a bent portion 37, and the distance L from the inner wall surface 38 of the casing 18 is shortened.

Conventionally, if the distance L between the tip of the electrode rod 23 and the inner wall surface 38 of the casing 18 is long, the flame of the premixed gas in the combustion chamber 32 cannot be detected accurately, and the Despite the fact that the gas was ignited, it was sometimes mistakenly detected as if it had been a misfire, which caused an accident.

As a result of repeating the experiment, the inventors have found that if the distance L between the electrode rod 23 and the inner wall surface 38 of the casing 18 is L ≦ 8 mm, the flame of the premixed gas can be reliably detected. Was.

In the present embodiment, taking such a point into consideration, a bent portion 37 is provided at the tip of the electrode rod 23 such that the distance L between the electrode rod 23 and the inner wall surface 38 of the casing 18 falls within the range of L ≦ 8 mm. It is formed.

Therefore, according to the present embodiment, since the bent portion 37 for shortening the distance L between the electrode rod 23 and the inner wall surface 38 of the casing 18 is formed at the tip, a safe and stable operation can be performed on the burner 17. Can be done.

In this embodiment, in order to reliably detect the flame of the premixed gas, the bent portion 37
The distance L from the inner wall surface 38 of the casing 18 is reduced. However, the present invention is not limited to this example. For example, as shown in FIG.
May be provided to shorten the distance L from the tip of the electrode bar 23.

FIG. 8 is a conceptual diagram showing an eighth embodiment of the combustion apparatus according to the present invention. In addition, the code added in the figure is
In the case of the same components as the conventional components shown in FIG. 11, the same reference numerals are used.

In the combustion apparatus according to this embodiment, when the main fuel nozzle 6 is ignited and the pilot fuel nozzle 15 is stopped, the temperature of the pilot fuel nozzle 15 rises due to the flame of the main fuel nozzle 6 and the burnout accident occurs. In consideration of the possibility of occurrence, a passage 40 for supplying a cooling medium to the stopped pilot fuel nozzle 15 is provided.

As described above, in this embodiment, the passage 40 is provided along the axial direction of the pilot fuel nozzle 15, and the cooling medium flows through the passage 40 to stop the pilot fuel nozzle 1.
5 is cooled, so that it is possible to reliably prevent the pilot fuel nozzle 15 from burning due to the flame from the main fuel nozzle 6.

FIG. 9 is a conceptual diagram showing a ninth embodiment of the combustion apparatus according to the present invention. In addition, the code added in the figure is
In the case of the same components as the conventional components shown in FIG. 11, the same reference numerals are used.

In the combustion apparatus according to the present embodiment, similarly to the eighth embodiment, a passage 40 is provided along the axial direction of the pilot fuel nozzle 15, and a cooling medium is caused to flow through the passage 40 so that the main fuel nozzle 6 In addition to preventing the pilot fuel nozzle 15 from burning out due to the flame, the pilot fuel nozzle 15 is provided with the electrode rod 23 shown in FIG.

As described above, in this embodiment, the passage 40 is provided in the pilot fuel nozzle 15 and the electrode rod 23
And the configuration is such that the ignition of the premixed gas and the detection of the flame of the main fuel nozzle 6 can be performed with one electrode rod 23.
The simplification of the structure can be further improved in combination with the prevention of the occurrence of burnout of the pilot fuel nozzle 15.

FIG. 10 shows a tenth embodiment of the combustion apparatus according to the present invention.
It is a key map showing an embodiment. The same components as those of the third embodiment are denoted by the same reference numerals, and only different components will be described.

The combustion apparatus according to the present embodiment has a DC / AC converter 42 in the ignition circuit 24 and the flame detection circuit 25 so that the DC power supply can be used when the power supplies are distributed.

Generally, both the ignition circuit 24 and the flame detection circuit 25 use an AC power supply. However, recently, with the practical use of fuel cells, each building and the like is increasing the number of distributed power sources.

In this embodiment, attention has been paid to such a point. A DC / AC converter 42 is provided in the ignition circuit 24 and the flame detection circuit 25, and in the case of a distributed power supply, a DC power supply is sufficiently used. It is made possible.

Therefore, according to the present embodiment, it is possible to quickly cope with the progress of the fuel cell.

[0064]

As described above, the combustion apparatus according to the present invention is provided with a means capable of satisfying different functions of ignition and flame detection with one electrode rod, so that the structure is simple and compact. Thus, a low-cost burner can be realized.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing a first embodiment of a combustion device according to the present invention.

FIG. 2 is a conceptual diagram showing a second embodiment of the combustion device according to the present invention.

FIG. 3 is a conceptual diagram showing a third embodiment of the combustion device according to the present invention.

FIG. 4 is a conceptual diagram showing a fourth embodiment of the combustion device according to the present invention.

FIG. 5 is a conceptual diagram showing a fifth embodiment of the combustion device according to the present invention.

FIG. 6 is a conceptual diagram showing a sixth embodiment of the combustion device according to the present invention.

FIG. 7 is a conceptual diagram showing a seventh embodiment of the combustion device according to the present invention.

FIG. 8 is a conceptual diagram showing an eighth embodiment of the combustion device according to the present invention.

FIG. 9 is a conceptual diagram showing a ninth embodiment of a combustion device according to the present invention.

FIG. 10 is a conceptual diagram showing a tenth embodiment of the combustion device according to the present invention.

FIG. 11 is a conceptual diagram showing a conventional combustion device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Flange 2 Fuel supply part 3 Combustion gas generation part 4 Air chamber 5 Fuel supply casing 6 Main fuel nozzle 7 Fuel guide tube 8 Air passage 9 Swirler 10 Air guide path 11 Air port 12 Combustion casing 13 Combustion chamber 14 Flame detector Reference Signs List 15 pilot fuel nozzle 16 ignition plug 17 burner part 18 casing 19 fuel port 20 air port 21 premixed gas passage 22 terminal 23 electrode rod 24 ignition circuit 25 flame detection circuit 26 switch 27 transformer 28 power supply 29 switch 30 flame detector 31 power supply 32 Combustion chamber 33 Switching relay 34 Switch 35 Contactor 36 Timer circuit 37 Bending portion 38 Inner wall surface 39 Projection piece 40 Passage 41 Solenoid valve 42 DC / AC converter

Claims (13)

[Claims] 1. A combustion device in which an electrode rod of an ignition plug is accommodated in a casing and a mixture of fuel and air is burned by a spark of the electrode rod, wherein an ignition circuit and a flame detection circuit are connected to the electrode rod. A combustion device characterized by the above-mentioned. 2. A combustion device in which an electrode rod of an ignition plug is housed in a casing and a mixture of fuel and air is burned by a spark of the electrode rod, wherein an ignition circuit and a flame detection circuit connected to the electrode rod include: Combustion characterized by comprising a switching relay and a switch, wherein when the switch is turned off, the switching relay switches to the flame detection circuit side, and when the switch is turned on, the switching relay switches to the ignition circuit side. apparatus. 3. The combustion device according to claim 2, wherein the switching relay is a vacuum relay. 4. The combustion device according to claim 1, wherein the ignition circuit includes a timer circuit in which a switching relay operates on the ignition circuit side with a time delay. 5. The combustion device according to claim 4, wherein the timer circuit is provided between the transformer of the ignition circuit and the power supply. 6. The combustion apparatus according to claim 1, wherein the flame detection circuit includes a timer circuit in which a switching relay operates on the flame detection circuit side with a time delay. 7. The combustion apparatus according to claim 6, wherein the timer circuit is provided between the flame detector of the flame detection circuit and the switching relay. 8. A combustion device in which an electrode rod of an ignition plug is housed in a casing and a mixture of fuel and air is burned by a spark of the electrode rod, wherein an ignition circuit and a flame detection circuit connected to the electrode rod include: A switching relay and a switch, wherein when the switch is turned off from on and the misfire of the air-fuel mixture is detected, a flame detector that gives a close signal to a solenoid valve provided on a fuel port side of the casing is used for the flame detection. A combustion device characterized by being incorporated in a circuit. 9. The electrode rod has a tip formed in a bent portion,
7. The combustion device according to claim 1, wherein the distance to the inner wall surface of the casing to be accommodated is reduced. 10. The combustion device according to claim 1, wherein the casing is provided with a projecting piece on an inner wall surface thereof to reduce a distance from the electrode rod. 11. A combustion apparatus comprising: a main fuel nozzle on a head side of a combustion chamber; and a flame detector and a pilot fuel nozzle in the combustion chamber in a direction intersecting the main fuel nozzle. A combustion device provided with a passage along a nozzle axial direction. 12. A combustion apparatus comprising: a main fuel nozzle on a head side of a combustion chamber; and a flame detector and a pilot fuel nozzle in the combustion chamber in a direction intersecting the main fuel nozzle. A combustion apparatus characterized in that an electrode rod is combined with the electrode rod, and the electrode rod is also used as a flame detector for the main fuel nozzle. 13. A combustion device for accommodating an electrode rod of an ignition plug in a casing and burning a mixture of fuel and air with a spark of the electrode rod, wherein an ignition circuit and a flame detection circuit are connected to the electrode rod. A combustion apparatus, wherein a DC / AC converter is provided in the ignition circuit and the flame detection circuit.