JP2000314509A - Burner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce NOx by providing a main burner port component made of a compact material, having a main burner port for forming a main flame by ejecting the residual part of mixture gas to a holding flame and improving flame formation for an object to be heated, thereby enhancing heat efficiency and furthermore increasing the air ratio. SOLUTION: A disc-like main burner port component 14 is tightened to the upper side of an annular casing 9 in a burner 100 and provided with a plurality of main burner ports 13 at fixed intervals in the circumferential direction, while being inclined to the upper part radially outward. Furthermore, a ring-like member 15 made of a felt-like metal fiber board and forming a flame-holding plane 18 is provided on the outside of the main burner port component 14. Consequently, total primary air type combustion, where variable range of combustion is enlarged and generation of NOx is suppressed by setting a higher air ration, can be realized. Furthermore, heat efficiency can be enhanced because the flame can be shaped according to an object to be heated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a burner apparatus in which a mixture of fuel gas and combustion air in a burner casing is ejected to perform all-primary air combustion.

[0002]

2. Description of the Related Art Heretofore, a burner apparatus for performing all-primary pneumatic combustion has a combustion surface made of a felt-like metal fiber plate or a porous ceramics plate, or a main flame hole formed by piercing a flame hole therethrough. Are known. In these burner devices, the flame is formed in a plane on the combustion surface, and it is difficult to form the flame obliquely upward so as to enclose a pan such as a stove in order to improve thermal efficiency. Further, in such a burner apparatus which performs all-primary air combustion, since the combustion is homogeneous, the range of the air ratio for stable combustion is narrow, and the air ratio is further increased to achieve a low NO.
It was difficult to achieve x conversion.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and in a burner apparatus for performing all-primary pneumatic combustion, it is possible to improve the thermal efficiency by improving the state of formation of a flame on an object to be heated. , Further increase the air ratio to lower NO
The purpose is to achieve x conversion.

[0004]

In order to achieve this object, a burner device according to the present invention is characterized in that a mixture of fuel gas and combustion air in a burner casing is provided. What is claimed is: 1. A burner device which ejects and performs all-primary pneumatic combustion, having a flame-extinguishing surface for ejecting a part of the air-fuel mixture to form a supplementary flame, and having a large number of holes communicating between the front and back surfaces. A main flame hole component member made of a dense material having a main flame hole for forming a main flame by ejecting the remainder of the air-fuel mixture to the supplement flame is provided.
That is, the air-fuel mixture seeping out from the flame-supplying surface from the flame-supplying surface member made of a porous plate material having a large number of holes communicating between the front and back surfaces forms supplementary flame with a stable combustion state. By injecting the air-fuel mixture from the main flame hole into the auxiliary flame, the main flame is always ignited by the auxiliary flame, and a stable all-primary pneumatic combustion can be realized. And a burner device that realizes low NOx combustion by setting the air ratio high. Further, since the main flame hole constituting member and the supplementary flame surface member are provided separately, for example, according to the shape of the object to be heated, the diameter of the main flame hole, the number, the ejection direction, etc., only the main flame hole constituting member Can be freely changed simply by changing.

[0005] In such a burner device, claim 2
As described in the above, it is preferable that the supplementary flame surface member is provided to be held by the main flame hole constituting member, with a simple configuration, the main flame hole constituting member can be freely selected,
Further, by providing a supplementary flame surface member on the side of the main flame hole constituting member, it is possible to constitute an all-primary pneumatic burner device which promotes the supplementary flame action.

Further, in such a burner device, the angle of the jetting direction of the main flame hole is within a range of 15 ° to 60 ° with respect to the supplementary flame surface. Preferably, there is. In this way, by setting the angle between the ejection direction of the main flame hole and the supplementary flame surface, the ignition state of the main flame by the supplementary flame becomes good, and the variable range of the combustion amount is further expanded. Set the air ratio high to reduce NO
All primary air combustion of x combustion can be realized. For example, it is possible to realize a burner device that changes the combustion amount within a range of 1.5 kW to 6 kW, and realize low NOx combustion in which the air ratio is set to, for example, about 1.4.

[0007] In such a burner device, the main flame hole constituting member and the supplementary flame surface member are preferably constructed as follows. That is, as described in claim 4, the main flame hole constituting member is a disk-shaped member having a plurality of the main flame holes in the circumferential direction, and the supplementary flame surface member is formed of the main flame hole. It is a member having a ring-shaped auxiliary flame surface on the radial outside of the hole constituting member. With this configuration, the main flame formed by the air-fuel mixture ejected from the main flame hole spreads outward upward and below the object to be heated, for example,
The flame wraps around the lower part of the object to be heated, and the thermal efficiency can be improved. Furthermore, since the auxiliary flame surface of the auxiliary flame surface member is configured so as to be below the main flame, it is possible to form the auxiliary flame that can ignite the main flame in a good state, and achieve an air ratio and It is possible to realize the all-primary pneumatic combustion in which the range of the combustion amount is further expanded, and to form a flame having a shape capable of favorably heating a heating object such as a pan.

Further, in such a burner device, it is possible to provide a cover member for refracting a jetting direction of the main flame hole to the side of the supplementary flame surface. That is, the air-fuel mixture ejected from the main flame is ignited by approaching the auxiliary flame surface by refracting the air-fuel mixture ejected from the main flame in the direction approaching the supplementary flame surface by the cover member. It becomes the main flame that goes around the member. Furthermore, when this burner device is used for a stove or the like, a cover member extending in a ring shape around the loading portion of the object to be heated in order to prevent the spill from a pan or the like from entering the main flame hole. Is provided so as to cover the upper part of the outlet of the main flame hole, and it is possible to prevent the blowout from the pan from directly hanging on the main flame hole to extinguish the flame, but this cover member is The air-fuel mixture ejected from the flame hole is refracted so as to approach the supplementary flame surface, so that the ignition state of the main flame by the supplementary flame can be improved, and the all primary air combustion that expands the range of the combustion amount and the air ratio is further improved. Can be realized.

Further, in the conventional burner device, as described in claim 6, it is preferable that the flaring surface member is made of a felt-like metal fiber plate or a porous ceramic. The air-fuel mixture oozing from the flame-supplying surface member burns when approaching the flame-supplying surface because of its low velocity. For that purpose, the material used as a flame-supply surface member is
It is necessary to consider heat resistance, and as the flame-supplying surface member in the present invention, it is made of a felt-like metal fiber plate or a porous ceramic which is excellent in heat resistance and can exude a mixture forming the flame-supplying. Can be used.

In order to supply a mixture for performing all-primary pneumatic combustion, these burners can be configured as follows. That is, as described in claim 7, a fuel nozzle for ejecting the fuel gas is provided, and a part of the combustion air is used by utilizing kinetic energy of the fuel gas ejected from the fuel nozzle. An ejector section for supplying the air; and an axial fan for supplying the remainder of the combustion air. In all primary pneumatic combustion,
All of the combustion air required for combustion is supplied as primary air, and the fuel gas and the primary air are mixed and burned.
In the burner device of the present invention, an inexpensive and small axial fan is used, a part of the combustion air is supplied by the axial fan, and the remaining combustion air, the so-called insufficient combustion air, is ejected by the ejector unit. It can be configured to be attracted by the ejection of the fuel gas in.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A configuration example of a burner device according to the present invention will be described with reference to FIG. Burner device 10 shown in FIG.
Numeral 0 denotes a burner device used for a rice cooker, which supplies all the combustion air A required for combustion as primary air, mixes it with fuel gas G, and jets out the mixture M to the combustion surface 17. Then, all primary pneumatic combustion is performed. Further, an axial fan 4 for supplying combustion air A to the gas flow path 6 side.
The axial fan 4 rotates and stops on the basis of an output signal from the control device 20. Although the axial flow fan is inexpensive and small, it is difficult to supply all of the combustion air A to the gas flow path due to the low static pressure. What has the blowing capacity of about 1/2 with respect to quantity is used. Therefore, the burner device 100 of the present invention includes the ejector portion 3 at a downstream portion of the axial fan 4 in order to supplement the blowing ability of the axial fan 4. The ejector portion 3 forms a flow path in which the position of the ejection port 2 of the fuel nozzle 1 is narrowed, and the ejection power of the combustion gas G ejected from the ejection port 2 to the gas passage 6 side causes the combustion air to be discharged. A can be attracted to the gas flow path 6 side. Result, axial fan 4
By means of the wind force and the attraction force at the ejector portion 3, all of the combustion air A required for combustion can be supplied to the gas flow path 6 side. Therefore, according to the supply state of the fuel gas G and the combustion air A, the air-fuel mixture M flows through the gas passage 6 and is supplied to the annular passage 10 formed by the annular casing 9.

Further, the burner device 100 is provided with a flow control valve 8 for adjusting the amount of fuel gas G to be injected in order to change the amount of combustion, and the opening of the flow control valve 8 is controlled by the control device 20. Can be set. That is, although the amount of air blown by the axial fan 4 is constant,
The amount of combustion air induced by the ejection of the fuel gas G changes in proportion to the ejection amount of the fuel gas G. As a result, even if the ejection amount of the fuel gas G is changed to change the combustion amount, the supply amount of the combustion air A can be changed and supplied according to the change, and the combustion amount can be changed. All primary air combustion can be realized.

Next, a description will be given of a configuration relating to a state of formation of a flame of all primary air combustion, which is a characteristic configuration of the present invention. The disc-shaped main flame hole forming member 14 is fastened to the upper side of the annular casing 9 of the burner device 100 of the present invention, and the main flame hole forming member 14 has a plurality of main flame holes arranged at equal intervals in the circumferential direction. 1
3 is provided with its upper part inclined outward in the radial direction. Further, a ring-shaped flame-supply surface member 15 made of a felt-like metal fiber plate that forms a flame-supplement surface 18 outside the main flame hole constituting member 14 is provided. With this configuration, a part of the air-fuel mixture M in the annular flow path 10 is formed in the main flame hole forming member 14 through the main flame opening 11 formed in the upper part of the annular casing 9. From the main flame hole 13 to the combustion surface 17 to form a main flame F and burn. Further, the annular flow path 10
The remainder of the air-fuel mixture M permeates out through the flame-supply opening 12 formed in the upper part of the annular casing 9 into the flame-supply surface 18 on the upper surface of the flame-supply surface member 15 to form a flame-supply F ′. Burn. By this, the supplementary flame F 'can always ignite the main flame F, and by this supplementary flame action, the variable range of the combustion amount is large and the all-primary pneumatic combustion in which the air ratio is set higher is realized. For example, even when the heating target is brought close to the combustion surface, the amount of combustion is set to 1500 to 4000 kcal.
/ H, and the air ratio can be set to about 1.3. In this case, a burner device in which the NOx concentration is suppressed to about 60 ppm and the thermal efficiency is improved can be configured. Further, the flame generated by the all-primary air combustion is a short flame, and can be satisfactorily heated even when an object to be heated is brought close to the burner device, which is advantageous in reducing the size of the device. Further, since the main flame F has a shape that spreads upward so as to enclose the object to be heated, for example,
A high-efficiency burner device having improved thermal efficiency to about 53% can be configured.

[Other Embodiments] (A) In the above embodiment, the configuration in which the amount of air blown by the axial fan 4 during the all-primary air combustion is constant has been described. Is configured to be controllable by the control device 20, and the fuel gas G
When changing the amount of combustion air, the amount of the combustion air A supplied by the axial fan 4 may also be changed. Further, all of the combustion air A can be supplied by a combustion fan, and the burner device of the present invention does not limit the supply state of the air-fuel mixture for performing all-primary air combustion.

(B) In the above embodiment, the burner device according to the present invention is described as a burner device used for a rice cooker. As shown in FIG. 2, a cover member 21 can be provided in which the upper portion of the main flame hole 13 of the main flame hole constituting member 14 is extended outward. It is possible to prevent extinction by preventing the main flame hole 13 from being caught. In this case, the air-fuel mixture ejected from the main flame port 13 is brought closer to the supplementary flame surface 18 side by this cover member, and the supplementary flame action is improved.

(C) Further, when the burner device of the present invention is used for a water heater using a heat exchanger as a heat-exchange object, for example, the main flame hole of the main flame hole constituting member is replaced with the shape of the heat exchanger. It can be formed in a shape according to the state, and can be configured to heat the heat exchanger satisfactorily.

Thus, in the burner device according to the present invention, it is possible to realize the all-primary pneumatic combustion in which the variable range of the combustion amount is expanded and the NOx is suppressed by setting the air ratio high. . Further, since the shape of the flame can be formed according to the object to be heated, the thermal efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an outline of a burner device according to the present invention.

FIG. 2 is a cross-sectional view showing another embodiment of the burner device according to the present invention.

[Explanation of symbols]

 Reference Signs List 6 mixture gas flow path 9 casing 13 main flame hole 14 main flame hole constituent member 15 supplementary flame surface member 18 supplementary flame surface 21 cover member 100 burner device A combustion gas G fuel gas M mixture F main flame F 'flame

Claims (7)

[Claims] 1. A burner device for injecting a mixture of fuel gas and combustion air in a burner casing to perform all-primary air combustion, wherein a part of the mixture is ejected to form a supplementary flame. A main flame that has a flame surface and is made of a porous plate material and has a large number of holes communicating between the front and back surfaces. A burner device including a main flame hole constituent member made of a dense material having a flame hole. 2. The burner apparatus according to claim 1, wherein the supplementary flame surface member is provided while being held by the main flame hole constituting member. 3. The burner device according to claim 1, wherein the angle of the ejection direction of the main flame hole is in a range of 15 ° to 60 ° with respect to the supplementary flame surface. 4. The main flame hole forming member is a disk-shaped member having a plurality of the main flame holes in a circumferential direction, and the supplementary flame surface member is disposed radially outward of the main flame hole forming member. The burner device according to any one of claims 1 to 3, wherein the burner device is a member having a ring-shaped supplementary flame surface. 5. The burner device according to claim 1, further comprising a cover member for refracting the ejection direction of the main flame hole toward the supplementary flame surface. 6. The burner device according to claim 1, wherein the supplementary flame surface member is made of a felt-like metal fiber plate or a porous ceramic. 7. An ejector section, comprising: a fuel nozzle for ejecting the fuel gas; and an ejector section for supplying a part of the combustion air by using kinetic energy of the fuel gas ejected from the fuel nozzle. The burner device according to any one of claims 1 to 6, further comprising an axial fan that supplies the remainder of the combustion air.