JPH0529805B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a combustor used in a heater or the like.

Conventional technology In general, this type of combustor vaporizes liquid fuel supplied from a nozzle in a vaporization cylinder, mixes it with combustion air supplied from an air supply pipe, and vaporizes a premixed gas of this air and fuel. Burning was performed by ejecting fuel from a burner head 1 at the top of the cylinder as shown in Figure 4, a vertically elongated main flame port 2 provided on the peripheral wall, and an auxiliary flame port 3 having a round hole.

Problems to be Solved by the Invention However, when the main flame port 2 of the combustor performs combustion with a minute combustion amount, the stability of the flame formed in the main flame port 2 and the fixation of the flame to the main flame port (hereinafter referred to as Due to the preheating of the auxiliary flame port 3, which is provided to improve the flame holding power (this is called flame holding power), there is a risk that the external porous tube 4 at the bottom of the main flame port may become particularly hot. It heated up abnormally, raising concerns about its durability.

In addition, since the main flame port 2 is vertically long, the flame becomes elongated and elongated, and it tends to lift easily, especially under conditions of excess air, causing the flame rod's flame current to drop suddenly and combustion to stop, etc.
The burn width was extremely narrow. This means that if the flame current value that stops combustion is set lower than before, the combustion width can be kept wide.
Due to poor flame stability, lowering the flame current setting would lead to combustion noise due to lifting combustion, carbon monoxide due to incomplete combustion, odor, etc., and could not be used in practice.

The present invention has been made in view of the above points, and aims to provide a highly reliable combustor that maintains a wide combustion width while improving durability.

Means for Solving the Problems In order to achieve the above object, the present invention provides a perforated cylinder on the inner periphery of the circumferential wall of a burner body and a rectifying cylinder closely attached to the perforated cylinder, and the rectifying cylinder has a vertically elongated main flame opening through a round hole. The lower part is a non-porous part and the part facing the vertically elongated upper part is a porous part with the border between the auxiliary flame ports as a boundary.

Effects With the above-described configuration, the present invention allows gas to be uniformly dispersed by the porous portion of the rectifying tube and directed toward the main flame port, and the gas path to the auxiliary flame port is lengthened, so that the gas flow velocity toward the auxiliary flame port is significantly reduced. Therefore, the auxiliary flame port becomes small, the thermal influence on the main flame port is reduced, and the temperature rise of the porous tube located at the main flame port can be significantly reduced.

In addition, because the gas is evenly distributed, the flame at the main flame port is well-balanced in the vertical direction, resulting in excellent stability and an extremely strong flame-holding ability that is difficult to lift. .

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. Reference numeral 11 denotes a bottomed cylindrical vaporizing/mixing cylinder, and a fuel supply nozzle 12 is installed at an eccentric position on a part of its peripheral wall. and an air supply pipe 13 for supplying combustion air. 14 is a heater embedded in the vaporizing/mixing cylinder 11; 15 is a burner body covering the upper opening of the vaporizing/mixing cylinder 11;
It has a narrow part 16 at the bottom that projects inward. Reference numeral 17 indicates a vertically elongated main flame port formed on the peripheral wall of the burner body 15, 17a indicates a circular auxiliary flame port formed at the bottom between the main flame ports 17, and 18 indicates a wire mesh, etc. attached to the inside and outside of the peripheral wall of the burner body 15. Burner body 1 is assembled by spot welding 18a between each flame hole using a multi-hole cylinder.
It is fixed at 5. Reference numeral 19 denotes a rectifying tube arranged so as to be in close contact with the internal porous tube 18 in the burner body peripheral wall;
This straightening tube 19 has a boundary between the vertically long main flame port 17 and the circular auxiliary flame port 17a, and its lower part is the non-porous part 1.
9a, the upper part facing the main flame port 17 is a porous part 19c having a plurality of small holes 19b. 2
0 is a pressure equalizing plate provided in the burner body 15, 2
1 is a double burner cap covered in the upper opening of the burner body 15, and 22 is a double burner cap 2.
1 is a nut for fixing it, 23 is a flame rod provided opposite to one of the main flame ports 17, and 24 is a burner case surrounding the vaporizing/mixing cylinder 11. The perforated cylinder 18 installed on the outer periphery of the side wall of the burner body 15 is supported in close contact with the burner body 15, with its lower end covered by the flange 11a of the vaporizer cylinder 11 and its upper end covered by the bent edge 21a of the burner cap 21. It is becoming more and more common.

In the above configuration, the fuel injected into the vaporization/mixing cylinder 11 by a pump or the like is transferred to the sheathed heater 1
Vaporizing/mixing cylinder 1 heated to high temperature by 4
1, and is vaporized and mixed using a blower etc.
It is premixed with the combustion air sent into the interior. This premixed vaporized gas flows into the burner body 15 through the narrow part 16 of the burner body 15 and the small holes 20a of the pressure equalizing plate 20 while swirling in the vaporizing/mixing cylinder 11, and flows into the main flame port 17 on the outer peripheral wall and the auxiliary flame. It is ejected from the mouth 17a. Then, when ignited with an appropriate ignition means, combustion starts and a flame is formed that is almost in close contact with the outer porous tube 18 around the main flame port 17 and the auxiliary flame port 17a.

Here, the flame formed at the main flame port 17 is
As shown in the figure, due to the presence of the rectifying tube 19, the mixed gas heading toward the main flame port 17 is uniformly dispersed in the porous portion 19c, resulting in excellent vertically balanced stability and lifting. It has a very strong flame-holding ability. In addition, auxiliary flame outlet 1
Since the mixed gas path up to 7a is much longer and narrower than before, as shown by arrow A in Figure 3, the flow velocity of the mixed gas toward the auxiliary flame port 17a is significantly reduced, and the auxiliary flame is small. As a result, the thermal influence on the main burner port 17 decreases, and the main burner port 17
The temperature rise in the porous cylinder located at the bottom can be significantly reduced.

Therefore, even if the ratio of fuel and air changes slightly, lift combustion will no longer occur, and problems such as flapping noise and carbon monoxide generation due to lift combustion will be eliminated, and the conventional lift combustion will not occur. Since the combustion range is stable up to a certain point, the combustion width can be further widened as a result.

Furthermore, as mentioned above, since the flame formed at the main flame port 17 is highly flame-holding and stable, the detection output of the flame rod 23 is naturally stable. Detection is also accurate with little variation. Moreover, at the time of ignition, the premixed gas ejected from each main flame port 17 is uniformly dispersed, so that the ignition progresses quickly.

Effects of the Invention As is clear from the above description of the embodiments, according to the present invention, the temperature of the porous body can be significantly lowered while maintaining a wide combustion range, and stable combustion performance is guaranteed under long-term use. It has great effects, such as being highly reliable and having a simple configuration, it can be provided at low cost.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of essential parts of a combustor according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of the entire combustor, FIG. FIG. 3 is a cross-sectional view showing a state of flame formation. 11...Mixing section, 15...Burna body, 17
... Flame hole, 18 ... Porous tube, 19 ... Rectifier tube, 1
9a... non-porous part, 19c... porous part.

Claims (1)

[Claims] 1. A mixing section that mixes air and fuel, and the mixed gas from the mixing section is combusted through a plurality of vertically elongated main flame ports provided on its outer peripheral wall and a circular auxiliary flame port provided at the bottom between the main flame ports. It is equipped with a burner body and a perforated cylinder arranged on the inner and outer peripheries of the peripheral wall of the burner body, and a rectifying cylinder that is in close contact with the perforated cylinder is arranged on the inner periphery of the perforated cylinder on the inner periphery of the peripheral wall of the burner body, and the rectifying cylinder is vertically elongated. A combustor with a non-porous part at the bottom and a porous part at the upper part facing the vertically elongated main flame port, with the boundary between the main flame port and the round auxiliary flame port.