JPS5912221A - Burner device - Google Patents

Abstract

PURPOSE:To provide stable combustion, by a method wherein a primary burner port part having a plurality of primary burner ports is covered with a container forming a primary combustion chamber, and a single secondary burner port with narrow width at the opposite ends thereof is provided in the container. CONSTITUTION:Gas fuel jetted through a nozzle 1 and entering through an inlet part 3 of the mixing tube of a burner 2 sucks as a primary air the air therearound by jet thereof, the air is mixed therewith in a mixing tube 4 to produce a combustible gas, and flame is produced by a plurality of primary burner ports 5. A single secondary burner port 6 with narrow width at the opposite ends thereof and a container 8 forming a primary combustion chamber 7 are constituted so as to cover the primary burner port 5 and the whole burner 2. A combustible gas in the mixing tube 4, being apt to be short of the air, flows in the primary burner port 5 to form a primary flame, but a unburnt gas finally makes contact with a secondary air above the secondary burner port to form a secondary flame brought to a perfect flame state.

Description

[Detailed Description of the Invention] Industrial Field of Application The present invention is suitable for household combustion appliances and has low NO! The present invention also relates to the field of combustion in which stable combustion is achieved even when atmospheric oxygen concentration is reduced.

Conventional configuration and its problems Most conventional household combustion appliances use Bunsen burners, so their NOx value is 100 to 150 ppm.
Therefore, it is desired to reduce NOx in indoor open appliances.

Low atmospheric pressure full-primary burners such as schbank burners have been put into practical use, but they have drawbacks such as high production costs, difficulty in achieving TDR, and a large projected area of the combustion part. Therefore, its use was limited to stoves, etc.

On the other hand, as shown in Japanese Patent Application No. 55-74810 shown in Fig. 3, a burner device has been proposed that divides the Bunsen burner into primary combustion and secondary combustion to reduce NOx. When burned, both ends of the secondary combustion flame tend to lift, particularly when the atmospheric oxygen concentration decreases, which tends to worsen combustion.

Purpose of the Invention The present invention improves the drawbacks of the conventional example.1 It provides a burner device that achieves low NOx, is capable of varying the combustion amount over a wide range, and can provide stable combustion even when the atmospheric oxygen concentration decreases. It is something.

Composition of the Invention The present invention divides the combustion flame of a Bunsen burner into primary combustion and secondary combustion by providing a primary combustion chamber, and achieves low NOx by lowering the flame temperature. By shortening the width of both ends of the single secondary flame port provided in the combustion chamber, stable combustion can be achieved even when the atmospheric oxygen concentration decreases, even during low-load combustion with a reduced combustion amount. .

DESCRIPTION OF EMBODIMENTS FIG. 1 is a perspective view showing the configuration of an embodiment of the present invention, and FIG. 2 shows Go/GO2 and NOx characteristics when the atmospheric oxygen concentration is reduced.

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. Gaseous fuel is ejected from a nozzle 1, enters a mixing pipe inlet 3 of a burner 2, and the jet sucks atmospheric air from the surroundings as primary air. At this time, the primary air amount is adjusted by using a damper or the like to adjust the diameter of the mixing tube inlet 3 so that the excess air ratio m is 0.6 to 0.9. The gaseous fuel and air are mixed in the mixing tube 4 to become a flammable gas and form a flame on the plurality of primary flame ports 5.

The secondary burner port 6 is a single burner port, but the width of both ends thereof is set to be shorter than that of the center portion. The burner device of the present invention is constructed by covering the primary flame port 5 or the entire burner 4 with the container 8 having the secondary flame port 6 set in this way and forming a primary combustion chamber.

In the above configuration, the reburnable gas in the mixing tube is in an air-deficient atmosphere, and in this state flows into the primary flame port to form a primary flame. The lack of air cannot be recovered because the primary flame port is covered by the primary combustion chamber, and the gas comes into contact with the secondary air cut off above the secondary flame port, where a secondary flame is formed. Become. In this way, the flame is separated into a primary flame and a secondary flame, and a stable flame is maintained at both flame openings.

Curves A and B in Figure 2 show the G O/G O□ characteristics when the amount of combustion is large (high load) and when the Inusamurai's waiting period is small (low load), respectively, and curves a and b are respectively when the amount of combustion is large. (high load), small (
This shows the NOx characteristics at low load.

Further, curves A', B', a', and b' show the characteristics corresponding to the above in the case of a conventional single rectangular secondary flame port of the same width.

When the atmospheric oxygen concentration decreases, the NOX characteristics are almost the same, but the reason why the CO/CO2 characteristics of the present invention are better is because the widths of both ends of the secondary flame mouth are shorter. This is because it prevents lift from occurring.

In addition, the above effect is remarkable when the combustion amount is small (low load).
This is natural from the fact that in the conventional example, both ends are easier to lift.

Furthermore, the reason why the NOx characteristics at low combustion rates are superior to the conventional example is that a small amount of secondary air flows into the primary combustion chamber from the secondary flame port, lowering the temperature of the primary flame. This point has also been improved in the present invention.

As a result, according to the burner device of this embodiment, the maximum temperature and average temperature of the flame are lower than the flame temperature of the conventional burner device, and this is caused by the decrease in flame temperature and the decrease in the 02 concentration at the maximum temperature. can control the generation of nitrogen oxides.

Furthermore, the CO/CO2 characteristics have been improved when the atmospheric oxygen level is lowered, and the effect is particularly great during low-load combustion, making it possible to significantly increase the TDR compared to conventional examples.

6 ＼ Incidentally, in this embodiment, we have described a configuration in which auxiliary air is frequently inserted into the primary combustion chamber, but even if the amount of primary air suction is reduced and the auxiliary air is supplied to the primary combustion chamber by that amount, the The same effect can be obtained.

Furthermore, although the primary combustion chamber has been described as covering the primary flame port, it goes without saying that it may cover the burner body excluding the suction port.

Effects of the Invention As described above, according to the burner device of the present invention, a plurality of primary flame ports or the entire burner are covered by a container forming a primary combustion chamber, and the width of both ends of the container is made shorter than the center portion. By providing a single secondary flame port, the structure can be simplified, the flame temperature can be lowered, and nitrogen oxides can be reduced.

Furthermore, with the above configuration, CO when the atmospheric oxygen concentration decreases.
The /CO2 characteristics are improved, especially the characteristics at low loads, and the TDR can be increased.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of page 7 showing an embodiment of the burner device of the present invention, and FIG. 2 is a co/
3 is a characteristic diagram showing a comparison of NOx characteristics with a conventional example. FIG. 3 is a perspective view showing the conventional example. 2...burner, 6...1 flame port, 6...
...2 flame ports, end...primary combustion chamber, 8...
··container. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Illustration θ:)10:)

Claims (1)

[Claims] A single flame port portion or a burner body having a plurality of single flame ports is covered with a container forming a primary combustion chamber, and a single two flame ports are provided in the container, and the width of both ends of the two flame ports is A burner device in which the center part is shorter than the center part.