JPS61289215A - Combustion device - Google Patents

Abstract

PURPOSE:To prevent flame from lifting at the flame port part of a combustion device when the combustion rate is large and, in addition, prevent the temperature of a wire netting from excessively rising when the combustion rate is small by a structure wherein a plurality of portions protruding toward the inner surface side onto the burning surface of a burner head and, in addition, a large number of small holes are perforated in the portions and, at the same time, the wire netting is provided on the outer surface side of the burner head so as to closely contact with the burner head. CONSTITUTION:A burner head 1 has a plurality of protruding portions 1' formed in the direction toward the inside of the burner head and is equipped with a plurality of small holes 2 perforated on respective said portions and with a wire netting 3 installed in closely contact with its outside. When the combustion rate is large, a large amount of premixed gas is jetted through the small holes 2 and the jetting speed of the gas is also faster. However, because the pressure of said gas decreases in small chambers 3' and consequently the speed of gas jetted through the openings of the wire netting 3 is lowered, the flames formed at the openings of the wire netting 3 do not lift from the wire netting 3 and the stable state of the flames is obtained. Even when the combustion rate is small or the jetting rate of premixed gas is small, its jetting speed through the small holes 3 is comparatively faster, and consequently no danger of backfiring into the burner head 1 occurs.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a burner for combustion equipment.

2. Description of the Related Art Conventionally, this type of combustion apparatus has a burner head 1 with a flame hole 2 as shown in FIG. 2 and a wire mesh 3 on the inner surface of the burner head 1, as shown in FIG. There is a structure in which a burner head 1 is provided with a flame hole 2 and a wire mesh 3 is provided on the outer surface of the burner head 1. (For example, Japanese Utility Model Application Publication No. 58-122817, Japanese Utility Model Application Publication No. 59-18121) Problems to be Solved by the Invention However, in the above configuration, one combustor has a wide range of combustion amount from large to small combustion amount. When adjusting the combustion amount within the range, it is necessary to suppress the injection speed of the premixed gas that is ejected from the flame hole 2 or the opening of the wire mesh 3 to below the combustion speed of the premixed gas when the combustion amount is large (injection When the speed is greater than the burning speed, the flame leaves the flame hole,
In severe cases, misfires occur) A large flame hole area is required to obtain an appropriate ejection velocity. - At the time of gal combustion, the combustion amount is reduced for the same flame opening area, so the ejection speed of the premixed gas decreases, flames are formed on the surface of the wire mesh 3, the temperature of the wire mesh 3 rises, and the material is damaged due to high temperature. There was a problem in that deterioration and deformation occurred due to alteration, making it difficult to maintain stable combustion.

Means for Solving the Problems In order to solve the above problems, the combustion device of the present invention provides a combustion surface of a burner head with a plurality of protrusions facing the inner surface, and the protrusions have small porous holes. In addition, a wire mesh is provided in close contact with the outer surface of the burner head.

Function According to the above configuration, the premixed gas ejected from the small hole of the burner head at the time of a large combustion amount is decelerated in the small chamber formed by the gap between the small hole and the wire mesh, and the flame is emitted using the opening of the wire mesh as the flame port. Since the ejection speed of the flame port is reduced in order to form the burner head, even when the ejection speed of the premixed gas ejected from the small holes of the burner head is high, it is possible to prevent the flame from leaving the flame port. - When the amount of gal combustion is reached, the ejection speed of the premixed gas decreases, flames are formed on the surface of the wire gauze, and the temperature of the wire gauze increases. Due to the structure, the heat contained in the wire mesh is transferred to the burner head by thermal conduction, and the temperature of the wire mesh is lowered by being cooled by the premixed gas passing through the inner surface of the burner head, which prevents deformation of the wire mesh and material deterioration due to high temperatures. This makes it possible to provide a combustion device in which the amount of combustion can be adjusted over a wide range without causing problems.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

In FIG. 1, a burner head 1 has a plurality of protrusions 1 formed inwardly. Reference numeral 2 designates a plurality of small holes drilled in the protruding portion 1, and reference numeral 3 designates a wire mesh closely attached to the outside of the burner head. A burner cap 4 covers the upper end of the wire mesh 2 and closes the upper end opening of the burner head 1. Reference numeral 5 denotes a vaporizing cylinder made of an aluminum die-cast molded product into which a heating heater 6 is cast, the upper end flange portion 7 of which covers the lower end of the wire mesh 3, and the burner head 1 is placed thereon. 8
1 is a gas passage constricted at the bottom of the burner head 1, 9 is a fuel nozzle, and 10 is a combustion air discharge port.

In the above configuration, the fuel supplied from the fuel nozzle 9 is heated and vaporized on the surface of the vaporization tube 5 heated by the heating heater 6, becoming gaseous, and mixed with the air supplied from the air discharge port 10, resulting in a premixed gas. The gas is then supplied to the internal space of the burner head 1 through the gas passage 8. The premixed gas receives heat from the inner wall surface of the burner head 1, is ejected from the small hole 2 into the small chamber 3' formed by the gap between the burner head 1 and the wire mesh 3, is depressurized, is ejected from the opening of the wire mesh 3, and is combusted. form a flame. When the combustion amount is large, the amount of premixed gas ejected from the small hole 2 is large and the ejection speed is high, but as mentioned above, the pressure is reduced in the small chamber 3 and the speed of ejection from the opening of the wire mesh 3 decreases. The flame formed at the opening of the wire mesh 3 does not separate from the wire mesh 3, and a stable state can be obtained.

When the combustion amount is 1 gal, the amount of premixed gas ejected is small, so the ejection speed is slower than when the combustion amount is large, and the combustion occurs very close to the surface of the wire mesh 3, so the temperature of the wire mesh 3 tends to rise. In addition, if the temperature of the premixed gas passing through the small chamber 3 rises due to the rise in the temperature of the wire mesh 3, and the ejection speed from the small holes 2 of the burner head 1 becomes slower than the combustion speed, there is a risk that the flame will backfire inside the burner head. be.

According to the configuration of the present invention, even in the case of a large combustion amount, the premixed gas is depressurized in the small chamber 3 and the ejection speed is reduced, so that the area of the small hole 2 is reduced in order to form a flame at the opening of the wire mesh 3. Even if the ejection speed is higher than the combustion speed, stable combustion can be achieved without the flame separating from the flame nozzle. The ejection speed is relatively fast, and there is no risk of backfire into the burner head 1, and further into the burner.

The surface of the door other than the protruding part 1 is in close contact with the wire mesh 3, and the heat received by the wire mesh 3 from the flame during small combustion is conducted to the burner head 1, where it is cooled by the premixed gas whose temperature is lower than the surface of the burner head 1. Therefore, the temperature of the wire mesh 3 is also difficult to rise.

If the wire mesh 3 is fixed to the burner head 1 by spot welding or the like, heat conduction can be further improved and a rise in temperature of the wire mesh 3 can be suppressed.

As described in detail, the combustion apparatus of the present invention (1) can prevent the flame from leaving the flame opening when the combustion volume is large, and prevent the temperature of the wire gauze from rising excessively when the combustion volume is small; As a result, there is no risk of backfire and the combustion amount can be adjusted over a wide range.

(2) The temperature of the wire mesh and burner head is low, resulting in stable combustion over a long period of time with little material deterioration or deformation due to high temperatures.

The following effects can be obtained.

[Brief explanation of drawings]

FIG. 1...Burner head, 1...Protrusion, 2...
...Small hole, 3 ...Wire mesh. Name of agent: Patent attorney Toshio Nakao (1 person)
Bar Tahe Ndo I'... Protrusion 1st Fig. 2... Small Jshi 3.
・Wire mesh 3′..., l・ Emperor

Claims (1)

[Scope of Claims] A combustion device in which a plurality of protrusions are provided on the inner surface of a burner head, a plurality of small holes are bored in the protrusions, and a wire mesh is closely attached to the outer surface of the burner head.