JPH0468531B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention is a burner for industrial/commercial use or household use that has a wide variable range of combustion heat (hereinafter referred to as TDR), and also has a wide variable range of combustion heat (hereinafter referred to as TDR), and also has an air-to-fuel ratio (hereinafter referred to as excess air). It concerns a large burner.

Conventional technology Conventionally, burners that utilize partial premixed sintering have been used as burners for industrial/commercial use or household heat sources, in which a premixed mixture of fuel and air is ignited above the flame hole. A premixed flame is formed, and secondary air is supplied from around the premixed flame to form a diffusion flame. This type includes the Bunsen burner, which is widely used.

Recently, in order to increase the TDR, a premixed counterflow burner has been proposed in which the premixed flames face each other and the flame is stabilized at the flame collision area.

Problem to be Solved by the Invention A burner that performs partial premix sintering, which forms a diffusion flame around a premixed flame, suddenly burns when the amount of heat sintered is small or when the excess air ratio of the premixed mixture approaches 1. Temperature rises and flashbacks often occur. If the amount of premixed air is increased to increase the excess air ratio, or if the amount of fuel is increased to increase the fuel flow rate, the flame will rise from the flame hole, making the flame unstable and preventing gas from flowing out. Ejection or blow-off often occurred. in this way,
The variable range of TDR and excess air ratio was small, which caused practical inconvenience.

On the other hand, a premixed counterflow flame burner, in which the premixed flames face each other and the flame is stabilized at the flame collision area, has the advantage of widening the variable range of TDR and excess air ratio, but the temperature of the wall of the combustion chamber becomes high. However, the durability of the heating chamber was poor and backfires easily occurred.

The present invention aims to solve the above problems.

Means for Solving the Problems The present invention relates to a premixed counterflow flame type burner, which has a wide TDR and a wide range of variable air excess ratio, and has a low burner temperature, so it has excellent durability. It can provide a good burner without backfire. The heat-burning chamber is divided into a primary heat-burning chamber that forms a premixed counterflow flame and a secondary heat-burning chamber that forms a diffusion flame. The heat-burning chamber is composed of heat-burning chamber walls, corresponding to the primary heat-burning chamber and the secondary heat-burning chamber,
It constitutes a primary heating chamber wall and a secondary heating chamber wall.

Further, in the present invention, a large number of flame holes are provided in the wall of the primary heating chamber forming the heating chamber. The flame holes are opposed to each other and are located at one end of a fuel supply passage provided in the wall of the primary heating chamber. The fuel supply path is provided outside the thermal firing chamber. The wall of the primary heating chamber is composed of a flat plate with a bent part, and the bent part is provided on the outside of the heating chamber to serve as a heat dissipation fin. Further, the heating chamber is configured with a plurality of flat plates using the bent portion as a connecting portion, and
After the secondary air cools the outer wall and radiation fins of the primary heating chamber, it flows into the secondary heating chamber.

Effect: When the excess air ratio is large and the amount of heat sintered is large,
The premixed flames are opposed to each other and burn out stably in the opposing parts, so the flame base does not blow away even if it moves away from the flame hole. In particular, the premixed flame formed in the flame hole near the exit of the heating chamber is heated by the high temperature exhaust gas generated by the premixed flame formed on the flame hole remote from the exit of the heating chamber. Because it heats gas, it has good flame stability and completely burns out the gas. Furthermore, since the flame is dispersed, even if the volume of the baking chamber is small, the baking can be done stably. In addition, by flowing secondary air through heat-burning chamber fins provided on the outer wall of the primary heat-burning chamber, the wall of the primary heat-burning chamber is cooled, thereby lowering the temperature of the burner and increasing the durability of the burner.

In addition, by arranging the opposing flame holes on the same axis,
A countercurrent flame is formed in the center of the heating chamber to prevent the burner temperature from rising. Furthermore, by serving as both a connection part and a heat dissipation fin, the temperature of the connection part is lowered and the durability of the burner is increased. Further, after the walls of the primary firing chamber are cooled by the secondary air, the high-temperature secondary air is used for firing the secondary flame. The secondary flame easily burns out completely.

Embodiment FIG. 1 is a partial cross-sectional configuration diagram of an embodiment of the present invention. 1 is the burner body, 2 is a thermal burning chamber, 3 is a primary thermal burning chamber, 4 is a secondary thermal burning chamber, 5 is a flame hole, 6 is a burner header, 7 is a secondary air hole, 8 is a fuel supply path, 9 is a Fuel branch pipe, 10 is a bent part, 11 is a header flange, 12 is a burner cover, 13 is a cooling passage, 14
is a secondary air passage, 15 is a bottom plate, 16 is a counterflow flame, 17 is a secondary flame, 18 is a premixture, 19 is a secondary air, 20 is a heating chamber wall, 21 is a primary heating chamber wall,
22 is a secondary heating chamber wall, 23 is an outer wall, 24 is an inner wall, 2
5 is an outlet of the heating chamber.

FIG. 2 is a cross-sectional configuration diagram of an embodiment of the present invention viewed from another direction. 26 slit-shaped flame holes. 2
7 is a partition plate, 28 is a fuel header, and 29 is a secondary air header.

FIG. 3 is a partial sectional view of FIG. 2. 31 is a connecting part fin. The heating chamber 2 consists of a primary heating chamber 3 and a secondary heating chamber 4, and the primary heating chamber wall 20 constituting the primary heating chamber 2 has several header flanges 11 lined up and facing each other. The bottom of the primary heating chamber 3 is formed by a rectangular bottom plate 15. At this time, a large number of flame holes 5 are provided in the wall 20 of the primary heating chamber. Heat-burning chamber outlet 2 of primary heat-burning chamber 3
In the five directions, secondary air holes 7 are arranged facing each other in the same way as the flame holes 5. A premixture 18 that is a mixture of fuel and primary air is supplied to a large number of fuel branch pipes 9 that constitute the burner header 6 .

The burner header 6 consists of a fuel branch pipe 9, a number of fuel supply passages 8, and a header flange 11. The burner flange 11 is made of a flat plate and has a bent part 10,
It is arranged so as to face the outside of the baking chamber 2. One end of the fuel supply path 8 becomes the flame hole 5, and the other end becomes the fuel branch pipe 9.
is connected to. A large number of secondary air holes 7 are provided in opposing secondary heating chamber walls 22, and are provided in large numbers facing a part of the burner cover 12.

In this embodiment, the burner header 6 is manufactured by pressing a stainless steel sheet metal. However, the fuel branch pipe 9, the fuel supply path 8, the primary thermal combustion chamber wall 21, etc. may be processed separately and connected by a connection method such as welding.

The secondary air passage 14 is an area surrounded by the burner cover 12 of the burner header 6, through which secondary air 19 flows. Each fuel branch pipe 9 has a large number of fuel supply channels 8.
has been established.

The fuel and the primary air are mixed to form a premixture 18, which passes through the fuel header 28, is supplied to the fuel branch pipe 9 connected thereto, passes through the fuel supply passage 8, and is sent from the flame hole 5 to the primary sintering chamber 3. gush. On the other hand, the secondary air 19 passes through the secondary air header 29 and is supplied to the cooling passage 13 communicating therewith. During firing, the primary firing chamber wall 20 and the fuel supply path 8 are cooled, and the fuel is supplied from the secondary air hole 7 to the secondary firing chamber 3 while increasing the temperature. Note that the cooling passage 13 forms a part of the secondary air passage 14. The secondary air passage 14 consists of a burner header 6 and a burner cover 12.

When the premixture 18 ejected from the flame hole 5 is ignited, a counterflow flame 16 is formed. Since the counterflow flame 15 often burns away from the flame hole 5 when the excess air ratio is large or the amount of heat sintered is large, a part of the premixture is discharged from near the flame hole 5 as it is. However, there are a plurality of flame holes 5 toward the heating chamber outlet 25.
are lined up, the premixed mixture 18 is completely scorched by the flame near the sintering chamber outlet 25. In addition,
When the excess air ratio of the premixture 18 is 1 or less, a secondary flame 17 is formed by the secondary air 19 supplied from the secondary air hole 7, and the pre-mixed gas is completely burned.

The feature of this embodiment is that in the burner where the premixed counterflow flame is formed, the outer wall 23 of the primary heating chamber wall 21 is cooled to prevent the temperature of the primary heating chamber wall 21 from rising.
The purpose is to improve the durability of the burner and prevent backfire, and the details will be described with reference to Figures 1 and 3. The high temperature sintering gas flows in the direction of the sintering chamber outlet 25 due to the counterflow flame 16 formed in the primary sintering chamber 3 . At that time, high temperature sintering gas and counterflow flame 1
The temperature of the primary heating chamber wall 21 increases due to the radiant heat 6. At this time, in order to prevent a temperature rise, the outer wall 23 of the primary heating chamber wall 21 serves as a cooling surface through which secondary air flows. A heating chamber fin 31 is provided on the outer wall 23 of the primary heating chamber wall 21. The heating chamber fin 31 is located within the cooling passage 12 within the secondary air passage 13,
The secondary air 19 flowing through the cooling passage 13 cools down the temperature of the primary heating chamber wall 21. Since the counterflow flame 16 has a flame stability region in the opposite part of the flame, the temperature of the primary heating chamber wall 21 decreases,
Even if the flame near the flame base is cooled, flame stability is not adversely affected.

As shown in FIGS. 1 and 3, the heating chamber fins 31 connect a part of the header flange 11 to the cooling passage 1.
It is formed by bending it on three sides. Primary heating chamber wall 2
1 has a large temperature rise as it moves away from the flame hole 5, but if the heating chamber fins 31 are arranged in the center of adjacent flame holes as shown in FIGS. 1 and 3, the cooling effect is large. Also,
The heating chamber fins may be fixed to the cooling passage 13 side of the primary heating chamber wall 21 by welding or the like.

A second example will be described. The flame holes 26 provided in the opposing primary heating chamber walls 21 are arranged coaxially. At this time, when the flow rate of the fuel increases, that is, when the amount of heating heat is increased, the flames collide and are formed in the center of the heating chamber. The flame is highest near the tip, and that high part is located in the center of the baking chamber, so it
1. Prevents temperature rise.

A third example will be described. The bent portion 10 is configured as a connecting portion of the header flange 11, and the primary heating chamber 3
facing outward. At this time, when the temperature of the connecting portion increases, deformation and deterioration are likely to occur, but the bending portion 10 is cooled by the secondary air 7 to lower the temperature of the connecting portion.

A fourth example will be described. When the cooling passage 13 is configured to be surrounded by the primary heating chamber wall 21, the fuel branch pipe 9, and the fuel supply path 8, it is possible to flow the secondary air 19 along the outer wall 23 of the primary heating chamber wall 21. can be,
Although the primary heating chamber wall 21 can be effectively cooled, the secondary air also receives heat from the heating chamber fins 31 at this time. As a result, the temperature of the primary heating chamber wall 21 can be reduced.

Effects of the Invention The present invention aims to lower the temperature of the heating chamber wall and the fuel supply path, thereby ensuring the durability of the burner and preventing backfire.
In the first invention, temperature rise in the primary heating chamber wall can be prevented by providing heating chamber fins on the outer wall of the primary heating chamber wall.

[Brief explanation of drawings]

FIG. 1 is a partial cross-sectional configuration diagram of a burner according to an embodiment of the present invention, FIG. 2 is a different cross-sectional configuration diagram of the same burner,
FIG. 3 is an enlarged view of the same burner. 1... Burner body, 3... Primary heating chamber, 5...
Flame hole, 18...primary heating chamber wall, 31...heating chamber fin.

Claims (1)

[Scope of Claims] 1. A large number of flame holes are provided in a primary combustion chamber wall constituting a combustion chamber, and the primary combustion chamber walls are arranged to face each other,
A fuel supply passage is attached to an outer wall of the primary combustion chamber wall, one end of the fuel supply passage is the flame hole, the primary combustion chamber wall is composed of a flat plate having a bent part, and the bent part is placed outside the combustion chamber. A burner equipped with a heating chamber with the outer wall as a cooling surface and the bent part as a heat radiation fin. 2. The burner according to claim 1, wherein the flame holes provided in the opposing primary combustion chamber walls are located coaxially with each other. 3. The burner according to claim 1, wherein the combustion chamber is constructed of a plurality of flat plates with bent portions serving as connecting portions. 4. In claim 1, the combustion chamber is composed of a primary combustion chamber and a secondary combustion chamber, the secondary combustion chamber is composed of opposing secondary combustion chamber walls, and secondary air is supplied to the secondary combustion chamber walls. A burner characterized in that a large number of secondary air holes are provided, and the secondary air flows through the outer wall of the primary combustion chamber.