JPS599143Y2 - combustion device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a combustion device incorporated in a forced air supply/exhaust type gas hot air heater or the like.

The combustor part in conventional combustion devices of this type is circular or line-shaped. In the case of a circular combustor, the combustor has the advantage of being short, but has the disadvantage of being thick due to its diameter. In the case of a linear type, the combustor had the advantage of being small in thickness, but had the disadvantage of being long.

Therefore, hot air heaters etc. using these combustion devices,
There is a problem in that the dimensions in the thickness direction or the length direction become large, and the installation area is required accordingly.

The present invention was developed in view of the above-mentioned disadvantages of conventional combustion devices, and by configuring the combustor and combustion tube in a substantially elliptical shape, only the advantages of both circular burners and linear burners can be utilized. By placing the flame port disposed in the combustor close to the inner wall of the combustion tube, the flame comes into contact with the combustion tube, lowering the flame temperature and reducing nitrogen oxides (NOx). ) The present invention aims to provide a combustion device that reduces the amount of emissions generated.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

The drawing shows a combustion device (not shown) installed in the main body of a gas hot-air heater, for example, and 1 is a combustion tube made of a metal with high thermal conductivity, such as aluminum, and shaped like an ellipse. , 2 is an intermediate ring provided with support arms 3, 3 for supporting and fixing a combustor 6, which will be described later; 4 is a blower guide airtightly connected to the combustion cylinder 1 via the intermediate ring 2 and a sealing member (not shown); A blower (not shown) is housed and fixed therein.

Reference numeral 6 denotes a combustor housed in the combustion tube 1 and having a substantially elliptical shape.
It is cut out from the flame outlet plate 9 and the air guide plate 10.

More specifically, the combustor main body 7 has a substantially elliptical ring shape, and the center part, the main body 7, and the combustion tube 1
An inner secondary air passage 11 and an outer secondary air passage 12 are respectively formed for supplying secondary air to the gap between the inner and outer secondary air passages.

Reference numeral 13 denotes a substantially elliptical annular mixing chamber formed within the combustor main body 7, which is divided into two chambers and communicated through a communication hole 14.

15 is a fuel injection nozzle facing the mixing chamber 13; 16 is a primary air supply port opening into the mixing chamber 13; the nozzle 15 faces into the mixing chamber 13 from the center thereof.

Near the circumference of the uniform plate 8 fixed to the thermal combustor main body 7, a plurality of independent gas holes 8a are arranged at equal intervals at positions closer to the center from the outer periphery of the combustor main body 7. 8a are bored, and these gas holes 8a, 8a communicate with the mixing chamber 13.

The flame port plate 9 has an elliptical ring shape similar to the uniform plate 8, and the flame port plate 9 is located inwardly from the outer circumferential surface of the combustor main body so as to correspond to the gas holes 8a, 8a on the outside. It is opened on the outer circumferential surface, and inner secondary air passage grooves 9b, 9b, which will be described later, are provided on the inner side.

The flame port plate 9 has its flame ports 9a, 9a connected to the gas holes 8a, 8.
It is fixed to the uniform plate 8 in alignment with a.

The air guide plate 10 is fixed to the passage grooves 9b, 9b side of the flame outlet plate 9, and its peripheral edge is tapered as shown.

The air guide plate 10 can also have a flat plate shape as a whole depending on the combustion mode.

The operation of the combustion device described above is as follows.

That is, first, when the blower is rotated, air A passes through the inner secondary air passage 11 as shown by the solid arrow in the figure.
At the same time, the outer secondary air passage 12 around the combustor 6
The fuel is sent to the front of the combustion tube 1, that is, to the left in FIG.

In this state, when fuel is injected from the nozzle 15 into the mixing chamber 13 as indicated by the dotted line arrow in the figure, air is sucked from the primary air supply port 16 as indicated by the dotted line arrow in the figure due to the injection action at that time. Ru.

This air mixes with the fuel as primary air to form a mixture.

The mixture is stored in a mixing chamber 1 which is divided into two chambers via a communication hole 14.
The gas is sent to the other chamber of 3, and the gas holes 8a, 8 of the uniform plate 8
a, it is ejected from the flame ports 9a, 9a of the flame port plate 9 toward the outer circumference of the flame port plate 9, and is ignited by an appropriate ignition means (not shown) to generate a primary flame f1.

In normal combustion, primary flame f1 causes excess fuel combustion and its temperature is low, so compared to Bunsen combustion, the amount of nitrogen oxides (NOx) generated is small, but carbon monoxide (CO ) is occurring.

However, in this device, the air sent by the blower is used as the inner secondary air through the secondary air passage groove 9b of the flame port plate 9,
9b to the inner periphery of the primary flame f1, and as outer secondary air to the outer periphery of the primary flame f1 via the outer secondary air passage 12, so the primary flame f1 is completely and safely combusted. This causes a secondary flame f2.

In this case, since the combustor 6 and the combustion tube 1 are close to each other,
Both the primary flame f1 and the secondary flame f2 come into contact with the inner wall of the combustion tube 1, and the flame temperature is further lowered, so that the amount of nitrogen oxides generated is further reduced.

Incidentally, the flame ports 9a, 9a of the combustor 6 are arranged inward from the outer peripheral surface of the combustor main body 7, which constitutes the inner wall of the outer secondary air passage 12, so that the outer secondary air is Even if the amount increases or decreases considerably, the base of the primary flame f1 is not disturbed and therefore no blowout occurs.

As described above, the combustion device of the present invention includes a combustor that includes a mixing chamber that mixes fuel and primary air, and a burner port plate that has a plurality of burner ports that blows out the mixture from the mixing chamber. In a combustion device supported within a combustion tube, the combustor and the combustion tube are shaped approximately elliptically, a secondary air passage is formed between the combustor main body and the combustion tube, and the flame port is formed. The flame plate is located inward from the outer circumferential surface of the combustor main body and is provided on the outer circumferential surface of the flame plate so that the flame generated at the flame port comes into contact with the inner wall of the combustion cylinder, making the combustor shorter and thinner. The amount of nitrogen oxides generated can be significantly reduced, and even if the amount of secondary air supplied is excessive, the amount of unburnt gas generated can be simultaneously reduced while preventing the flame from blowing out. This makes it possible to reduce the thickness and size of a hot-air heater, etc., and to improve combustion performance.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of a combustion apparatus according to the present invention, and FIG. 2 is a sectional view taken along the line II--II in FIG. 1... Combustion cylinder, 6... Combustor, 9...
...flame port plate, 9a, 9a...flame port.

Claims (1)

[Scope of utility model registration request] In a combustion device in which a combustor is supported in a combustion cylinder, the combustor includes a mixing chamber for mixing fuel and primary air, and a flame plate having a plurality of flame ports for blowing out the mixture from the mixing chamber. The combustor and the combustion tube are shaped approximately elliptically, a secondary air passage is formed between the combustor body and the combustion tube, and the flame port is located inward from the outer peripheral surface of the combustor body. A combustion device characterized in that a flame plate is provided on the outer circumferential surface of the flame plate so that the flame generated at the flame port comes into contact with the inner wall of a combustion cylinder.