JPS6082709A - Infrared ray burner - Google Patents

Abstract

PURPOSE:To improve radiation efficiency and a rapid head effect, by a method wherein a plurality of projections are provided on the surface of a burner plate formed by a heat- resistant ceramic, a plurality of burner ports are formed on the outer periphery thereof, and an irregular size burner port, having a large size at the top (gas injection nozzle), is formed in the approximately central part of the projection. CONSTITUTION:An air-fuel mixture, mixed with a primary air in a mixing chamber 14, flows through burner ports 10 and an irregular size burner port 11 in a burner plate 7, and is burnt on the surface. The air-fuel mixture through the burner ports 10 prevents the occurrence of a lift by virtue of the heat insulating effect of a V-groove part M, and heats a slanted part into red hot state. The air-fuel flowing in through the upper stream side of the burner port 11, formed in the about central part of a projection 8, i.e., the small size burner port is decreased in a velocity of gas flow at the enlarged part, and prevents the occurrence of lift. Further, the projection 8 is thin in a thickness wall and low in a heat capacity, and this ensures uniformly heating-to-red hot state and a high surface temperature and provides high radiation. The burner plate 7 is made of heat-resistant ceramic consisting of mainly alumina and silica and has a number of feed burner ports formed in the total area thereof, and this prevents the occurrence of backfire even when a surface temperature is maintained at a high value.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an infrared burner with improved radiation efficiency.

Structure of the conventional example and its problems As shown in FIGS. 1 and 2, the conventional infrared burner of this type has a plurality of V-grooves that intersect with each other in the horizontal and vertical directions on the surface of the burner plate 10. There is a plate configuration in which a plurality of flame holes are formed at the bottom of the outer periphery of the protrusion 2. The ejected gas from the nozzles 3 and 2 is ejected into the mixing tube, and the primary air necessary for combustion is sucked in and mixed into the mixing chamber 4. burner play 1・
It burns on the surface of the flame hole 5 of No. 1 (near the exit "J") and mainly makes the protrusion 2 red-hot. No. 6 indicates a filler material.

In this configuration, since the flame hole 5 is provided only at the bottom of the outer periphery of the protrusion 2, the heat of the protrusion 2 is indirectly heated by the combustion heat of the flame hole 5 at the bottom of the outer periphery, so that the red-hot temperature is low. High radiation cannot be obtained. In addition, if the flame hole is provided in the center of the protrusion 2, the gas passage resistance increases, the amount of ejected gas decreases, and the degree of redness decreases.For city gas systems, the diameter of the flame hole is reduced to about 1 to prevent backfire. Since it requires a small diameter of .0 mm, it is easy to lift due to changes in excess air ratio (m value), and as a result, the degree of redness decreases rapidly, making it difficult to obtain high radiation efficiency. .

In addition, as an infrared burner, there is a known infrared burner, such as a metallic burner that burns combustion gas on the surface of a metal wire gauze (Schbank burner plate 1-1) in which flame holes are provided in a ceramic plate, thereby making the wire gauze red-hot.

3) Shebunk burner plates have the disadvantage that they tend to crack due to heating and cooling of the plates, which shortens their service life. Furthermore, since the thermal conductivity of the ceramic plate itself is relatively high, if the temperature of the combustion surface exceeds 900°C, the temperature on the back side of the plate, especially near the flame hole, will rise, igniting the air-fuel mixture and creating the risk of backfire. . Therefore, although a combustion surface temperature of 900°C or higher is desired from the perspective of radiation efficiency, it is not possible to keep the combustion surface temperature below 900°C from the viewpoint of the life of the ceramic plate and the safety of the burner. The current situation is that Metallic burners have the characteristics of a short rise time after ignition until reaching red-hot temperature, and are easy to process.However, because they have low corrosion resistance at high temperatures, it is necessary to raise the temperature of the combustion surface to increase radiation efficiency. What you expect is actually impossible.

OBJECT OF THE INVENTION The present invention solves such conventional problems. Gases with markedly different combustion properties are combusted well, the combustion surface accelerates red heat, and a high combustion surface temperature is obtained. The purpose is to provide an effective infrared burner.

Structure of the Invention The present invention comprises a plurality of protrusions on the surface of the burner plate,
A plurality of flame holes are provided on the outer periphery of the protrusion, and flame holes of different diameters are provided approximately in the center of the protrusion, with the upper part (gas outlet) having a larger diameter.

With this configuration, the combustion heat in the flame holes on the outer periphery of the protrusion and the combustion promotion in the central part of the protrusion promote stable red-hot formation of the protrusion even with gas types with different combustion speeds, and promote high red-hot glow. The temperature can be maintained.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to FIGS. 3 and 4. In Figures 3 and 4, 7 is alumina A 12
03, burner plate mainly composed of silica 5102, 8
A plurality of quadrangular pyramid-shaped protrusions are provided on the surface of the burner plate 7, and are composed of a plurality of V grooves M that intersect with each other in the horizontal and vertical directions, and a flat portion 9 is formed on the upper surface. 10 is a flame hole provided at the bottom of the outer periphery of the protrusion 8, and the inner diameter is 1°0 to 1.1 m.
A plurality of small holes of m are bored at a pitch of 5 pages. 11 is a flame hole with different diameters, and one side (Ganu ejection side) has a large diameter (1.3 to 2.0 mm).
), its upstream side has the same diameter as the flame hole 10, and the protrusion 8
It is located approximately in the center of the 12 is a nozzle, 13 is a mixing tube, 14 is a mixing chamber, and 15 is a filler.

In the above configuration, the gas ejected from the nozzle 12 is ejected into the mixing tube 13, and the air-fuel mixture sufficiently mixed with the primary air in the mixing chamber 14 passes through the flame port 10 of the burner plate 7 and the flame hole 11 of different diameter. As a result, combustion occurs on the surface (near the outlet) of the flame port 10.11.

At this time, complete combustion occurs due to the supply of secondary air, and the plate surface, especially the 11th protrusion, becomes red hot.

That is, the air-fuel mixture from the flame port 10 burns near the outlet of the flame hole 10, preventing lift due to the heat retention effect of the V-groove M portion, and causing the sloped portion of the V-groove M portion to become red hot.

Since the flame holes 10 are provided at the bottom of the outer periphery of the protrusion 11 with appropriate gaps, there is no interference between the flames, and a stable supply of secondary air is obtained, further promoting complete combustion.

Furthermore, an enlarged 6 bevel 7 is provided at the exit portion provided approximately in the center of the protrusion 11.
Since the flame holes 11 with different diameters are provided, the flame holes 11
The gas flow velocity of the air-fuel mixture flowing in from the upstream side of the flame hole, that is, the small-diameter flame hole, decreases at the enlarged portion, and the gas ejection speed at the outlet of the flame hole 11 becomes weaker, thereby completely preventing the lift. Stable flame stability can be ensured near the outlet. As a result, the vicinity of the flat part 9 of the protrusion 8 becomes red-hot intensively.

Furthermore, since the protrusion 8 is penetrated with an enlarged diameter, the wall thickness is thin, and the heat capacity is small.
The red heat of the protrusion 8 is further promoted by the concentrated heating at the emerging part of the flame hole 11, resulting in uniform red heat and high surface temperature (for example, 950°C).
A high-radiation infrared burner that ensures high radiation (~1050°G) can be obtained.

The burner plate of the present invention is formed into a plate shape using a ceramic structure made of a composite of heat-resistant medium ramic fibers mainly composed of alumina A 1203 and silica 5i02, and has a thermal conductivity of 0.1 Kcal/m-h'. As a plate smaller than C, we have provided as many holes as possible with a total diameter of 1.0 to 1 mm for supplying the air-fuel mixture throughout the plate, so even when the surface temperature is maintained at a high temperature of 9507 to 1050°C. Also conventional
: Sea urchin will not cause backfire. Furthermore, the protrusion 8
Combined with the concentrated heating, the red heat rise time can be greatly shortened (for example, about 30 seconds to reach 750° C.), and an infrared burner with high heating speed can be provided.

Effects of the Invention As described above, the present invention includes a plurality of protrusions on the surface of the burner plate, a plurality of flame holes at the bottom of the outer periphery of the protrusions, and an exit hole with a diameter approximately at the center of the protrusions. Since the flame holes with large diameters and different diameters are provided, (1) the surface temperature of the plate can be maintained at a high temperature (for example, 950 to 1050° C.), and an infrared burner having high radiation efficiency can be provided.

2 The red heat rise time becomes faster due to the concentrated heating of the protrusion.

(a) An infrared burner can be provided that prevents backfire and lift and can handle reburned gas types with different properties.

[Brief explanation of drawings]

Figure 1 is a sectional view showing a conventional infrared burner, Figure 2a,
FIG. 3 is a sectional view showing an embodiment of the infrared burner of the present invention, and FIGS. 4a and 4 b are a sectional view and a plan view of the same essential part. 7...Burner plate, 8...-Protrusion,
10... Flame hole, 11... Flame hole of different diameter. Name of agent: Patent attorney Toshio Nakao et al. Famous confectionery 1
Figure 2 (of) 2 Figure 3 3 Figure 4 (a,) (b)

Claims (1)

[Claims] The burner plate is formed of heat-resistant ceramic mainly composed of alumina and silica, and has a plurality of protrusions on the surface of the burner plate, a plurality of flame holes provided at the bottom of the outer periphery of the protrusions, and An infrared burner with flame holes of different diameters, one with a larger diameter, approximately in the center.