JP2003240351A - Combustion device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a combustion device wherein the production of NOx is suppressed without impairing the workability in assembling. <P>SOLUTION: A combustion chamber body is secured on a burner box top plate with screws to prevent a gap from being made between the combustion chamber body and the burner box top plate, and a secondary air from entering the base flame portion of the burner through the gap. The angle of the screws fastening the combustion chamber body flange on the burner box top plate end is inclined relative to the vertical line in order to allow screwing work to be carried out through an air intake, thus improving the workability in screwing. <P>COPYRIGHT: (C)2003,JPO

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, there is a combustion apparatus of this type as shown in FIG. In FIG. 5, 51 is a main body case, 52 is an air intake port provided on the back surface of the main body case, 5
3 is an air outlet, 54 is an air intake 52 to the main body case 51
An air blower for taking in air, 55 is a stand, 56 is a burner including a mixing tube 57 and a flame hole portion 58, 59 is a burner box that houses the burner 56, 60 is an igniter, 61 is a combustion chamber main body 62 and a combustion chamber shield. The combustion chamber is formed by integrally forming a heat plate 63, and a secondary air introduction hole 64 for introducing air from the blower 54 into the combustion chamber body 62 is provided on the back surface of the combustion chamber body 62.

The burner box 5 is placed on the stand 55.
9 on which the combustion chamber body 62 and the combustion chamber heat shield plate 63 are placed.
The combustion chamber 61 composed of the above is mounted, and the flange portion 65 of the combustion chamber main body 62 is inserted into the fitting portion 67 of the burner box upper plate 66 as shown in FIG. It is designed to be fixed.

In the above-described structure, when the operation is started, the liquid fuel is heated and vaporized by a vaporizer (not shown) to become vaporized gas, which is jetted into the mixing pipe 57. At this time, ambient air is also drawn into the mixing pipe 57 as primary air. In addition, as shown by the black arrow in FIG.
The air introduced into the device by the rotation of 4 is also pushed into the mixing pipe 57 as primary air, mixes with the above-mentioned vaporized gas to form a mixed gas, and is ignited by the ignition device 60 and burned in the flame hole portion 58. .

Further, the air from the blower 54 flows into the combustion chamber main body 62 through the secondary air introduction hole 64 provided on the back surface of the combustion chamber main body 62, and is supplied to the flame as secondary air for combustion. Has become. Then, the amount of secondary air is adjusted depending on the number of holes in the flame hole portion 58, the position of the secondary air introduction hole 64, etc. to reduce the NOx.

[0006]

However, as described above, the combustion chamber body and the burner box are only indirectly contacted by inserting the flange portion of the combustion chamber body into the fitting portion of the burner box upper plate. Therefore, for example, when the table is bent or the combustion chamber is deformed, a slight gap may occur between the combustion chamber body and the burner box upper plate. Then, the air from the blower flows into the flame hole portion of the burner through the gap as secondary air. Then, the combustion reaction becomes vigorous in the vicinity of the flame hole of the burner into which the secondary air flows, and as a result, there is a problem that a high flame temperature portion is generated and a large amount of NOx is generated. It was

Therefore, as a method for reducing NOx, it is conceivable to fix the combustion chamber body and the burner box upper plate from the inside with screws or the like to prevent a gap from occurring, as shown in FIG. However, in order to screw the combustion chamber body and the burner box upper plate after placing the combustion chamber on the burner box, a hand with a screwdriver must be put inside the combustion chamber body, but Since the front part of the hot plate covers the upper part of the combustion chamber main body, the space for putting in a hand is narrowed, and it is expected that screwing will be considerably difficult and workability will be deteriorated.

The secondary air for combustion has a structure to be introduced into the main body of the combustion chamber through a secondary air intake hole provided on the rear surface of the main body of the combustion chamber. It is taken as it is and supplied to the flame. Therefore, not only is it difficult to suppress NOx because the secondary air also flows into the burner's flame hole, it is not possible to obtain the secondary air evenly with respect to the flame, and there is also the problem that the flame foot extends. there were.

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

[0010]

In order to achieve the above object, the present invention provides a burner having a burner box upper plate for accommodating a burner and an air intake provided on the back surface of a main body case for taking in outside air by a blower. Combustion chamber body that covers the flame of the burner and discharges combustion exhaust gas upward, combustion combustion gas that covers the combustion chamber body, mixes the combustion exhaust gas and air from the blower, and guides it as hot air to the outlet on the front of the main body case In a combustion device including a chamber heat shield plate, a screwing portion is provided on the air intake side in order to fix a flange portion formed on a lower rear portion of the combustion chamber body and an end surface portion of the burner box upper plate. At the same time, the screw mounting angle of the screw fixing portion is inclined toward the air intake side with respect to the vertical direction, and the combustion chamber body and the burner box are fixed by screwing from the air intake side. Those relating to the combustion apparatus, characterized by.

Further, the present invention relates to the combustion apparatus according to claim 1, further comprising an air flow rate adjusting metal fitting for guiding the air from the blower into the combustion chamber body on the back surface of the combustion chamber body.

Further, the present invention relates to the combustion apparatus according to claim 1 or 2, wherein the tip of the end face portion of the burner box upper plate is folded back toward the combustion chamber body.

According to the configuration of the present invention, the combustion chamber body and the burner box upper plate are firmly fixed by screws or the like, and even if the stand is slightly bent or the combustion chamber is deformed, Since there is no gap between the upper plates of the burner box, secondary air does not flow into the burner flame holes, and NOx generation can be suppressed. Further, since the combustion chamber body and the burner box can be screwed from the air intake side, the screwing workability is improved.

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

Further, since the tip of the end face of the burner box upper plate is folded back toward the combustion chamber body to increase the rigidity of the end face of the burner box upper plate, deformation of the screwed portion can be prevented and flatness can be secured. In addition, since the flange portion of the combustion chamber body is wrapped around, it is possible to reliably prevent secondary air from flowing into the combustion chamber body from the gap of the burner box upper plate.

[0015]

Embodiments of the present invention will be described below with reference to FIGS.
I will explain based on. In FIG. 1, 1 is a body case, 2
Is an air inlet provided on the back surface of the main body case 3, 3 is a blower outlet for discharging hot air to the outside, 4 is a blower for taking air into the main body case 1 from the air intake 2, 5 is a stand, and 6 is for combustion. A hot air passage for mixing the generated combustion exhaust gas and the air from the blower 4 to form hot air into the air outlet 3, 7 is a burner composed of a mixing tube 8 and a flame hole 9, and 10 is a burner accommodating the burner 7. Box, 11 is burner box top plate, 12
Is an ignition device, 13 is a combustion chamber body 14 and a combustion chamber heat shield plate 15.
Is a combustion chamber consisting of.

Further, as shown in FIG. 2, a secondary air introducing hole 16 and an air volume adjusting metal fitting 17 for introducing the air from the blower 4 into the combustion chamber body 14 are provided on the back surface of the combustion chamber body 14. . The air volume adjusting fitting 17 has a shape having an air intake port at a position corresponding to the rotation direction of the blower 4 so that a large amount of dynamic pressure air from the blower 4 can be taken into the combustion chamber main body 14, and the secondary air is provided. It is attached so as to cover the introduction hole 16.

Further, the combustion chamber body 14 and the combustion chamber heat shield plate 15
Are integrally formed, and as shown in FIG.
4 is placed on the burner box upper plate 11, and the combustion chamber body 14
It is configured to be fixed with a screw 21 at a screw-fastening portion 20 composed of a flange portion 18 at the lower part of the back surface and an end surface portion 19 of the burner box upper plate 11. Further screwed part 2
The mounting angle of the screw 21 of 0 is inclined toward the air intake port 2 side by a constant angle (θ) with respect to the vertical direction.

Here, the reason why the screw 21 of the screw fixing portion 20 is inclined at a constant angle (θ) toward the air intake 2 side is that when the flange portion 18 and the end surface portion 19 are fixed with the screw 21 from the vertical direction. In this case, since the combustion chamber heat shield plate 15 and the air volume adjusting metal fitting 17 interfere with the workability of fixing the screw 21, the screw 21 can be directly fixed by the driver 22 from the air intake 2 side as shown in FIG. Therefore, the workability of fastening the screw 21 is improved step by step. Although the angle of inclination (θ) varies depending on the position of the screwing portion 20, the position of the air intake 2, etc., the angle is not limited as long as the screw 22 can be directly screwed by the driver 22.

Further, as shown in FIG. 3, the tip of the end surface portion 19 of the burner box upper plate 11 is folded back toward the combustion chamber main body side to increase the rigidity of the end surface portion, so that the screwing portion is prevented from being deformed and flat. And the combustion chamber body 14
Since the flange portion 18 of the combustion chamber body 1 is wrapped around the flange portion 18,
It can be surely prevented from flowing into 4.

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 vaporized gas, which is ejected from the nozzle into the mixing pipe 8. When the vaporized gas is ejected, the ambient air is drawn into the mixing tube 8 as primary air by the ejection force. In addition, the air introduced into the main body case 1 by the rotation of the blower 4 is also shown by the black arrow in FIG.
From the lower part of the burner box 10 is pushed into the mixing tube 8 as primary air, and these primary air is mixed with the above-mentioned vaporized gas to form a mixed gas, which is ignited by the ignition device 12 and starts combustion in the flame hole 9.

Further, the air from the blower 4 also flows into the combustion chamber main body 14 through the secondary air introduction hole 17 provided on the back surface of the combustion chamber main body 14 and is supplied to the flame as secondary air. ing. At this time, the air from the blower 4 hits the air volume adjusting fitting 16 provided so as to cover the secondary air introducing hole 16, and is rectified so as to flow into the flame at a substantially right angle. Since a sufficient amount is supplied to the vicinity of the flame tip without flowing into the flame hole 9 of the burner 7, it is possible to maintain a good combustion state, reduce NOx, and shorten the flame.

The combustion exhaust gas generated by combustion is
While passing through the warm air passage 6, the air is mixed with the air from the blower 4 to become warm air, which is discharged from the air outlet 3.

In addition, the table 5 may be bent or the combustion chamber 13 may be deformed by heat with long-term use. In such a case, if the burner box 10 and the combustion chamber main body 14 are not firmly fixed, a gap is generated between the burner box upper plate 11 and the combustion chamber main body 14 due to the deformation of the mounting table 5 and the combustion chamber 13, Secondary air flows into the flame hole portion 9 of the burner 7 through this gap. However, the combustion apparatus of the present invention is configured so that the burner box upper plate 11 and the combustion chamber body 14 are
Since it is firmly fixed with screws, no gap is created between the burner box upper plate 11 and the combustion chamber body 14 even if the stand 5 and the combustion chamber 13 are slightly deformed. The secondary air of the burner 7 has a flame hole 9
It is possible to prevent this from flowing into the air, and to suppress the generation of NOx.

[0024]

As described above, in the combustion apparatus of the present invention, the combustion chamber body is fixed to the burner box upper plate with screws, so that even if the table is bent or the combustion chamber is deformed, Since there is no gap between the chamber and the burner box upper plate, it is possible to prevent secondary air from flowing into the flame hole portion of the burner from here and suppress the generation of NOx. In addition, the screw mounting angle between the combustion chamber body and the upper part of the burner box is inclined by a certain angle with respect to the vertical direction and screwed from the air intake, so workability when screwing is improved. Can be greatly improved.

Further, in the second aspect of the invention, the secondary air from the blower is rectified by the air flow rate adjusting metal fitting provided on the back surface of the combustion chamber main body so as to be substantially perpendicular to the flame, and then the secondary air is introduced. Since it is introduced, secondary air can be prevented from flowing into the flame hole of the burner, and a sufficient amount of secondary air can be supplied near the tip of the flame.
Will be reduced.

Further, in the invention according to claim 3,
Since the tip of the end face of the burner box top plate is folded back inward to increase the rigidity of the end face of the burner box top plate,
The flatness is secured by preventing deformation of the screw fastening part, and the flange part of the combustion chamber body is wrapped, so it is possible to ensure that secondary air flows into the combustion chamber body from the gap of the burner box upper plate. Can be prevented and NOx
Is reduced.

[Brief description of drawings]

FIG. 1 is a combustion device 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 sectional view of a combustion chamber main body and a screw fastening portion of a burner box according to an embodiment of the present invention.

FIG. 4 is an explanatory diagram illustrating a screwing operation for the combustion chamber body and the burner box according to the embodiment of this invention.

FIG. 5 is a conventional combustion device.

FIG. 6 is an explanatory diagram illustrating a mounting state of a combustion chamber and a burner box in a conventional combustion device.

FIG. 7 is an explanatory diagram illustrating a screwed state of a combustion chamber and a burner box in a conventional combustion device.

[Explanation of symbols]

1 body case 2 Air intake 3 outlet 4 blower 7 burners 10 burner box 11 Burner box upper plate 14 Combustion chamber body 15 Combustion chamber heat shield 18 Flange 19 End face 20 Screw stop 21 screws

Claims (3)

[Claims] 1. An air intake provided on the back of a main body case for taking in outside air with a blower, a burner box having a burner box upper plate for accommodating a burner, a burner flame is covered, and combustion exhaust gas is discharged upward. In a combustion device comprising a combustion chamber main body, a combustion chamber heat shield plate that covers the combustion chamber main body, mixes combustion exhaust gas and air from the blower, and guides it as hot air to a blowout port on the front surface of the main body case, A screw fastening portion is provided on the air intake side to fix the flange portion formed on the lower rear portion of the main body and the end surface portion of the burner box upper plate, and the screw mounting angle of the screw fastening portion is set to the vertical direction. The combustion chamber body and the burner box are fixed by screwing them from the air intake side. 2. The combustion apparatus according to claim 1, further comprising an air flow rate adjusting metal member provided on a rear surface of the combustion chamber body for guiding air from the blower into the combustion chamber body. 3. The burner box upper plate has a tip end portion of an end face portion folded back toward the combustion chamber main body.
Alternatively, the combustion device according to claim 2.