JP2002323261A - Combustion equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide combustion equipment, in which generation of NOx can be suppressed without impairing workability in assembling. SOLUTION: A combustion chamber body and a burner box are secured with screws, etc., to prevent a gap from being formed between the burner box and the combustion chamber and a secondary air from flowing into the base flame part from the gap. The front wall of a heat-shield plate is divided from a heat-shielding plate, so that workability in screwing will not be impaired.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion device such as a fan heater and, more particularly, to a structure of a combustion chamber for reducing NOx.

[0002]

2. Description of the Related Art Conventionally, as a combustion apparatus of this type, FIGS.
The following are known. In FIG.
Is a table, 22 is a blower, 23 is a mixing tube 24 and a flame hole 25
26, a burner box containing a burner 23; 27, an ignition device; 28, a combustion chamber formed integrally with a combustion chamber body 29 and a heat shield plate 30;
A secondary air introduction hole 31 for introducing air from the blower 22 into the inside of the combustion chamber is provided on the back surface of 9. Then, the burner box 26 is placed on the mounting table 21, and the combustion chamber 28 is placed on the burner box 26. As shown in FIG. It is designed to be hooked and fixed.

In the above-described configuration, when the operation is started, the liquid fuel is heated and vaporized by a vaporizer (not shown) to become a vaporized gas, and is discharged into the mixing pipe 24. At this time, the surrounding air is also drawn into the mixing tube 24 as primary air. Also, as shown by the black arrow in FIG.
As the 2 rotates, the air introduced into the apparatus is also pushed into the mixing pipe 24 as primary air, mixed with the above-mentioned vaporized gas to form a mixed gas, ignited by the ignition device 27 and burned in the flame hole 25. .

Further, air from the blower 22 is supplied from a secondary air introduction hole 31 provided on the back of the combustion chamber main body 29 to the combustion chamber 2.
8 and is supplied to the flame as secondary air for combustion. The amount of secondary air is adjusted according to the number of holes in the flame hole portion 25 and the position of the secondary air introduction hole 31 to reduce NOx.

[0005]

However, since the combustion chamber body and the burner box only indirectly adhere to each other by hooking the flange to the upper plate of the burner box as described above, for example, the mounting table is bent. When the combustion chamber is deformed, a slight gap may be formed between the combustion chamber main body and the burner box. And
From the gap, air from the blower flows into the burner hole of the burner as secondary air. Then, there is a problem that the combustion reaction is violently performed in the vicinity of the burner hole portion of the burner into which the secondary air has flowed. Was.

Therefore, as a method for reducing NOx, it is conceivable to fix the combustion chamber body and the burner box from the inside with screws or the like so that no gap is formed.
However, in order to screw on the combustion chamber after placing it on the burner box, the hand holding the screwdriver must be put into the combustion chamber, but the front part of the combustion chamber heat shield is located above the combustion chamber. , The space for entering the hand is narrow, and it is expected that screwing will be quite difficult and workability will deteriorate.

The secondary air for combustion is introduced into the combustion chamber through a secondary air intake hole provided on the back of the main body of the combustion chamber, and the air sent by the rotation of the blower is taken as it is. Supplying flame. As a result, the secondary air also flows into the flame hole of the burner, and N
Not only is it difficult to suppress Ox, but there is also a problem that secondary air cannot be obtained evenly with respect to the flame, and the fire foot extends.

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a combustion apparatus capable of suppressing generation of NOx without impairing workability during assembly.

[0009]

In order to achieve the above object, the present invention provides a burner for burning liquid fuel, a burner box containing the burner, a combustion chamber mounted on the burner box, The combustion chamber has a blower that sends secondary air for combustion into the combustion chamber, and the combustion chamber is formed by integrally forming a heat shield plate with a heat shield plate and attaching a heat shield plate front wall to the heat shield plate, The combustion chamber main body is fixed to the burner box with screws or the like, and relates to a combustion apparatus.

The combustion apparatus according to claim 1, further comprising an air volume adjusting fitting for guiding air from a blower into the combustion chamber on a back surface of the combustion chamber main body.

[0011]

According to the above construction, the combustion chamber main body and the burner box are firmly fixed by screws or the like. Therefore, even when the mounting table is slightly bent or the combustion chamber is deformed, the combustion chamber main body and the burner box are not fixed. Since there is no gap between the burner boxes, the secondary air does not flow into the flame hole of the burner, and the generation of NOx can be suppressed.

Further, by providing the air volume adjusting metal fitting on the back surface of the combustion chamber main body, a sufficient amount of secondary air can be supplied near the front end of the flame, so that the NOx can be further reduced.

[0013]

1 to 3 show an embodiment of the present invention.
It is explained based on. In FIG. 1, 1 is a table, 2 is a blower, 3 is a hot air passage for mixing combustion gas generated by combustion with air from the blower 2 to generate hot air, and 4 is a blower for discharging hot air to the outside. An outlet 5 is a burner comprising a mixing tube 6 and a flame hole 7, 8 is a burner box containing the burner 5, 9
Reference numeral 10 denotes an ignition device, and 10 denotes a combustion chamber including a combustion chamber main body 11, a heat shield plate 12, and a heat shield plate front wall 13.

As shown in FIG. 2, a secondary air introduction hole 14 for introducing air from the blower 2 into the combustion chamber 10 and an air volume adjusting fitting 15 are provided on the back of the combustion chamber main body 11. The air volume adjustment fitting 15 has a shape having an air intake at a position corresponding to the rotation direction of the blower 2 so that a large amount of dynamic pressure air from the blower 2 can be taken into the combustion chamber. It is attached so that it covers.

As shown in FIG. 3, the combustion chamber main body 11 and the heat shield plate 12 are formed integrally, and this integrally formed product is placed on the burner box 8 and the combustion chamber main body 11 is placed at several places from the inside. It is configured to be fixed to the burner box 8 by screwing. And the heat shield plate front wall 1
Numeral 3 is attached to the heat shield plate 12 after fixing the combustion chamber main body 11 and the burner box 8.

Here, in the conventional structure, the heat shield plate front wall 1
3 was integrated with the heat shield plate 12, so that when viewed from the front of the combustion chamber 10, the heat shield plate front wall 13 covered the space inside the combustion chamber 10 from above. Therefore, the combustion chamber body 1
In order to screw the burner box 1 and the burner box 8 from the inside, a hand must be inserted through a slight gap between the heat shield plate front wall 13 and the burner box. The inside becomes hard to see. Therefore, if the heat shield plate front wall 13 and the heat shield plate 12 are divided so that the heat shield plate front wall 13 can be attached later, the one that covers the inside of the combustion chamber 10 when viewed from the front may be used. As a result, a sufficient working space for screwing the combustion chamber body 11 to the burner box 8 can be secured,
Workability is greatly improved.

Next, the operation of the above configuration will be described. When the operation is started, the liquid fuel is heated and vaporized by a vaporizer (not shown) to become a vaporized gas, and is ejected from the nozzle into the mixing pipe 6. When the vaporized gas is ejected, the surrounding air is drawn into the mixing pipe 6 as primary air by the ejection power. The air introduced into the apparatus by the rotation of the blower 2 is also pushed as primary air from the lower part of the burner box 8 into the mixing pipe 6 as shown by the black arrow in FIG. The mixture is mixed to form a mixed gas, which is ignited by the ignition device 9 and starts burning in the flame hole 7.

Further, the air from the blower 2 is supplied to the combustion chamber 1 through a secondary air introduction hole 14 provided on the back of the combustion chamber main body 11.
It also flows into the inside of the cylinder and is supplied to the flame as secondary air. At this time, the air from the blower 2 is supplied with an air volume adjusting bracket 15 provided so as to cover the secondary air introduction hole 14.
, The air is rectified so as to flow at substantially right angles to the flame, and the secondary air does not flow into the flame hole 7 of the burner 5 and a sufficient amount is supplied to the vicinity of the flame front end. It is possible to reduce NOx while maintaining a good combustion state, and shorten the flame.

The combustion gas generated by the combustion is mixed with the air from the blower 2 while passing through the hot air passage 3, becomes hot air, and is discharged from the outlet 4.

In addition, the table 1 may be bent or the combustion chamber 10 may be deformed by heat with long-term use. If the burner box 8 and the combustion chamber main body 11 are not firmly fixed, a gap is formed between the burner box 8 and the combustion chamber main body 11 due to the deformation of the mounting table 1 and the combustion chamber 10. Secondary air flows into the flame hole 7. However, since the burner box 8 and the combustion chamber main body 11 are firmly fixed with screws in the combustion apparatus of the present invention, even if the mounting table 1 and the combustion chamber 10 are slightly deformed, the burner box 8 and the combustion chamber main body 11 are not fixed. Since no gap is generated between the burners 5, the secondary air from the blower 2 can be prevented from flowing into the flame hole 7 of the burner 5.
The generation of NOx is suppressed.

FIG. 4 is a graph showing measured values of NOx emitted from the conventional and the present invention. As can be seen from this graph, the combustion apparatus of the present invention can reduce the emission by about 20% as compared with the conventional apparatus.

[0022]

As described above, in the combustion apparatus according to the present invention, the combustion chamber main body is fixed to the burner box with screws or the like. Therefore, even if the mounting table is bent or the combustion chamber is deformed, the combustion chamber is not damaged. Since no gap is formed between the burner and the burner box, it is possible to prevent the secondary air from flowing into the flame hole of the burner from here, thereby suppressing the generation of NOx. Further, since the front wall of the heat shield plate is configured to be attached later, it is possible to secure a wide working space for screwing, and does not impair workability.

In the second aspect of the present invention, the secondary air from the blower is rectified so as to be substantially at right angles to the flame by the air volume adjusting bracket provided on the back surface of the combustion chamber main body. Can be prevented from flowing into the flame hole of the burner, and a sufficient amount of secondary air can be supplied near the front end of the flame, so that NOx can be further reduced.

[Brief description of the drawings]

FIG. 1 is a combustion apparatus according to an embodiment of the present invention.

FIG. 2 is a rear perspective view of the combustion chamber according to the embodiment of the present invention.

FIG. 3 is a detailed view of a combustion chamber portion according to the embodiment of the present invention.

FIG. 4 is a graph showing NOx emissions in the present invention and a conventional combustion device.

FIG. 5 is a conventional combustion device.

FIG. 6 is a detailed view of a combustion chamber portion of a conventional combustion device.

[Description of Signs] 5 burner 8 burner box 10 combustion chamber 2 blower 11 combustion chamber main body 12 heat shield plate 13 heat shield plate front wall 15 air volume adjustment bracket

Claims (2)

[Claims] 1. A burner for burning liquid fuel, a burner box for storing the burner, a combustion chamber mounted on the burner box, and a blower for sending secondary air for combustion into the combustion chamber. The combustion chamber is formed by integrally forming a heat shield plate with a combustion chamber body and attaching a heat shield plate front wall to the heat shield plate, and the combustion chamber body is fixed to the burner box by screws or the like. A combustion device characterized by the following. 2. The combustion apparatus according to claim 1, further comprising an air volume adjusting metal member for guiding air from a blower into the combustion chamber on a back surface of the combustion chamber body.