JPH0820057B2 - Premixed gas burner - Google Patents

Description

TECHNICAL FIELD The present invention relates to a premixing type gas burner used in a gas water heater or the like.

[Conventional technology]

It is strongly desired to reduce the size of household gas water heaters in terms of improved installation, harmony with buildings, and effective use of dead space.

Conventionally, gas water heaters use Bunsen gas burners that are effective for air-fuel ratio controllability and flame stability, and various forms that promote secondary air diffusion to enable high-load combustion. Has been proposed.

In addition, the study of a high-load combustion system that uses a fully premixed gas burner that does not require the diffusion of secondary air has been attempted.

[Problems to be solved by the invention]

In order to make the gas water heater compact, it is necessary to downsize the combustion part, the combustion space, etc., which have a high volume ratio in the product.

However, when the Bunsen type gas burner is used, it is possible to reduce the combustion space to some extent as a short flame by promoting the diffusion of secondary air, but it is difficult to make the product significantly compact.

On the other hand, in the case of the all-premixed gas burner, it is not necessary to diffuse the secondary air, so that the flame can be shortened and the combustion space can be made smaller than in the case of the Bunsen type gas burner. However, increase the air ratio (ratio of the air-fuel air amount to the theoretical air amount) to maintain the balance between the ejection speed of the premixed gas from the flame mouth and the combustion speed and prevent the flame from blowing out. I can't. As a result, the combustion gas becomes hot and the concentration of environmental pollutants such as carbon monoxide (hereinafter CO) and nitrogen oxides (NOx) in the combustion gas becomes high, and the dew point due to low air ratio combustion As a result, the corrosive drain is likely to be generated at the time of heat exchange between the combustion gas and water due to the rise of the exhaust gas, so that there is a drawback that a drain treatment device is required. Also, in the case of a gas with a high combustion rate, flashback may occur depending on the conditions, and the size at which the premixed gas at the flame mouth ejects must be less than the extinction distance, which increases the pressure loss at the burner and There is a drawback that the fan that sends air becomes large. Further, there are various problems such that a device for premixing the fuel gas and the combustion air is required and the cost is increased.

An object of the present invention is to provide a premixed gas burner capable of high-load combustion without the above-mentioned drawbacks.

[Means for Solving Problems] and [Embodiment] The structure of the premixing gas burner according to the present invention will be described with reference to the embodiments shown in FIGS. 1 to 4.

1 is a plan view of a premixed gas burner of the present invention, FIG. 2 is a side view, FIG. 3 is a sectional view taken along line AA of FIG. 1, and FIG.
The drawing is a sectional view taken along line BB in FIG.

Basically, a burner plate 1 and a gas distribution pipe 4 having a gas inlet 2 at one end and the other end connected to the burner plate 1.
And an air supply means having an air inlet pipe 3 at one end and an air distribution pipe 5 connected to the burner plate 1 at the other end. Also, burner plate 1
Four groove portions 10 are formed at equal intervals on the upper surface of the. 8
8 are gas outlets provided at equal intervals in the central vertical direction of the bottom surface 10a of each groove 10, and 9 are air jets provided on both side surfaces 10b of the groove 10 corresponding to the positions of the gas ejection holes 8. It is the exit.

Reference numeral 6 is a gas supply passage formed in the lower portion of each groove portion 10 of the burner plate 1, and a gas ejection hole 8 is provided through a vertical branch hole 13.
, And one end of the opening is connected to a gas distribution pipe 4 having a gas inlet 2.

7 is a gas supply passage 6 at the bottom of the burner plate 1.
It is an air supply path that is provided between them, and is connected to the air ejection port 9 through a vertical branch hole 13 and a horizontal branch hole 11 or 12, and one end opening portion is connected to an air distribution pipe 5 having an air inlet 3. are doing.

[Action]

The present invention is configured as described above, and the fuel gas is guided to the gas inlet 2 and the burner plate 1 is provided in the gas distribution pipe 4.
The gas spouts 8 which are evenly distributed in the plurality of gas supply passages 6 formed in the inside of the burner plate 1, flow into the burner plate 1 through the gas supply passages 6 and pass through the vertical branch holes 13 and open to the bottom surface 10a of the groove 10.
Squirt out uniformly.

On the other hand, the combustion air is guided to the air inlet 3, is evenly dispersed in the plurality of air supply passages 7 formed in the burner plate 1 in the air distribution pipe 5, and flows into the burner plate 1 through the air supply passages 7. The air outlet 9 that opens from the vertical branch 13 to the horizontal branch 11 or 12 and opens on both side surfaces 10b of the groove 10
The gas flows out of the fuel gas in a direction orthogonal to the fuel gas, so that the mixing with the fuel gas is instantly completed. In this way, gas and air are supplied independently, so there is no need to secure a flame-extinguishing distance to prevent flashback without causing flashback during combustion, and it is possible to downsize the fan by reducing pressure loss. Become.

Also, even if the air ratio is increased, it does not blow off, so the combustion temperature, which strongly affects the production of CO, NOx, etc., can be easily adjusted by changing the amount of air, and it suppresses environmental pollutants. You can Further, since the fuel gas and the combustion air are instantaneously mixed in the groove portion 10 of the burner plate 1, high load combustion equal to or more than that of the all-premix burner can be obtained, and the burner plate 1 itself is a mixer. As a result, the mixer required in the case of the all-premix burner is not necessary.

The premixing type gas burner according to the present invention is not limited to gas, and can be applied to the case of vaporizing and burning liquid fuel such as kerosene.

〔The invention's effect〕

According to the premixed gas burner according to the present invention, CO while performing high-load combustion equal to or more than the premixed gas burner,
It is possible to easily reduce the generation of NOx and the like, and it is possible to downsize or omit the components that form the combustion device, which makes it possible to make the product compact and reduce the cost.

[Brief description of drawings]

1 is a plan view of a premixed gas burner of the present invention, FIG. 2 is a side view of FIG. 1, FIG. 3 is a sectional view taken along line AA of FIG. 1, and FIG. 4 is B- of FIG. It is a B sectional view. Explanation of symbols 1 ... Burner plate, 2 ... Gas inlet 3 ... Air inlet, 4 ... Gas distribution pipe 5 ... Air distribution pipe, 6 ... Gas supply passage 7 ... Air supply passage, 8 ... Gas Jet 9: Air jet 10, 10: Groove 10a: Bottom, 10b: Side 11, 12, 13 ... Branch hole

Claims (4)

[Claims] 1. A burner plate, and gas supply means and air supply means connected to the burner plate, wherein a plurality of groove portions are provided on the upper surface of the burner plate, and a large number of gas ejection ports are provided on the bottom surface of the groove portion. Further, the premixed gas burner is characterized in that a large number of air ejection ports are provided on the side surface of the groove. 2. The air jet outlets are formed on both side surfaces corresponding to the gas jet outlets provided at equal intervals in the vertical direction on the bottom surface of the groove portion. Premixed gas burner. 3. The gas supply means is connected to the gas ejection port through a plurality of branch holes formed in the burner plate through a plurality of gas supply passages from the gas distribution pipe. A premixed gas burner according to item 1. 4. An air supply means is connected to an air ejection port through a plurality of branch holes formed in a burner plate through a plurality of air supply passages from an air distribution pipe. A premixed gas burner as described in the item.