JPH0210338B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a liquid fuel combustion device that burns liquid fuel.

Conventional technology In recent years, household heating equipment that burns oil and uses its combustion heat has improved ease of use, comfort, indoor pollution, and
Due to the growing awareness of energy saving, etc., the fuel is gasified and burned inside the box case, rather than the open flame type heater that uses conventional lamp wicks etc. to make a wire mesh red hot and directly heats with the radiant heat. Hot-air fans that blow hot air using a convection fan installed in a room to heat the room are becoming mainstream. Furthermore, with regard to the latter type of hot-air type combustion appliances, there is a demand for an expanded range of variable combustion amount due to the above-mentioned heightened awareness, and various combustion methods have been developed and improved.

An example of the conventional combustion appliance mentioned above will be described below with reference to the drawings.

FIG. 3, FIG. 4, and FIG. 5 are an overall sectional view, an exploded view of a burner portion, and a plan view of a burner portion of a conventional combustion appliance.

In FIG. 3, reference numeral 1 denotes a combustion blower with a built-in fan and motor, and its outlet is connected to an air pipe 4 to a throat 3 attached to the side of the vaporizing cylinder 2. The air pipe 4 incorporates a solenoid valve 5 having a small hole valve. A bypass air passage 6 is provided between the electromagnetic valve 5 and the combustion blower 1, and the bypass air passage 6 is connected to a burner case 7 attached to cover the vaporization cylinder 2. Inside the throat 3, one side is opened into the vaporization cylinder 2, and the other side is connected to an oil tank receiver 9 via a pump 8.
It has a nozzle 10 that is open. 11 is an oil tank. The vaporization tube 2 is constructed by embedding a sheathed heater in the outer periphery of a cylindrical body with a bottom, and a vaporization tube lid 12 with an opening in the center is placed on top of the vaporization tube lid 12, and a cylindrical body with an open end and an opening on the side is placed on top of the vaporization tube lid 12. A pressure equalizing plate 17 having a plurality of small holes is provided inside the burner head 16 above the opening of the vaporizer cylinder lid 12, and these are connected by bolts provided on the vaporizer cylinder lid 12. It is installed. An earth plate 13 is attached to the outer periphery of the burner head 16, the lower part of which fits into the side surface of the vaporizer cylinder 2, and the upper part of which faces the opening of the burner head 16.
The upper surface of the burner case 7, which is provided to cover the vaporizing cylinder 2, is formed into a flat surface, and a flame rod 14 is attached to the flat surface. Frame rod 14
The frame rod 1 has an outer periphery made of an insulator 14a, a conductor 14b passing through the center part, one end bent to a position facing the opening 16a of the burner head 16, and the other end passing through the outside of the burner case 7.
The structure is such that a constant voltage is applied between the conductor 14b of No. 4 and the burner head 16.

The operation of the combustion appliance configured as described above will be explained below.

First, the fuel sent out by the pump 8 is transferred to the carburetor cylinder 2.
It is squirted inside. The inside of the vaporization cylinder 2 is heated to a high temperature by a sheathed heater, so the ejected fuel vaporizes and mixes with the air sent from the throat 3, and is heated to the opening of the vaporization cylinder lid 12 and the small part of the pressure equalization plate 17. through the hole and through the side opening 16 of the burner head 16.
It ejects from a. Opening 16 of burner head 16
When the ejected gas is ignited by an ignition means such as a discharge spark of an ignition electrode near point a, a flame 18 is formed at the side opening 16a of the burner head 16 as shown in FIG. On the other hand, the conductor 1 of the frame rod 14
When a constant voltage is applied between 4b and the burner head 16, a current flows through the flame when combustion is normal. Furthermore, if the amount of air sent from the throat 3 is varied in accordance with the amount of fuel sent out by the pump 6, the amount of combustion can be changed.

Problems to be Solved by the Invention However, with the above configuration, it is difficult to have a wide variable range of combustion amount. For example, if the balance between the amount of fuel sent from the pump 6 and the amount of air sent from the throat 3 is slightly disrupted due to assembly variations, dirt clogging, etc., defective combustion such as lift combustion will immediately occur. Furthermore, if the variable range of the combustion amount is increased, the amount of fuel sent from the pump 6 must be varied from large to small, and the amount of air sent from the throat 3 must also be varied from large to small, making the setting extremely difficult to balance. becomes.

Furthermore, when switching the combustion amount, the above-mentioned balance between the amounts of fuel and air is likely to collapse, and misfires, yellow flames, and abnormal combustion accompanied by soot are likely to occur, which necessitates the need for various countermeasures.

Also, in the flame state, the conductor 14 of the flame rod 14
A constant voltage is applied between B and the burner head 16, and the current value that flows is detected. However, the normal output is different depending on when the combustion amount is high and low, and since the current value is low, there is a difference between normal combustion and poor combustion. There have been problems in that it is difficult to make comparisons, and when variations are taken into consideration, settings are difficult and costly.

In view of the above-mentioned problems, the present invention expands the amount balance range of fuel and air and increases the amount of current detected in the flame state, thereby widening the variable range of combustion amount and providing a combustion appliance that is stable over time. It provides:

Means for Solving the Problems In order to solve the above problems, the combustion appliance of the present invention includes a burner body that covers the upper part of the vaporizing cylinder and has a plurality of pores in the side wall, and a burner body that is tightly attached to the outer periphery of the side wall and has a plurality of pores. A wire mesh-like flame-holding cylinder provided to cover the burner head also constitutes the burner head, and the burner body is made of a heat-resistant austenitic metal with a large thermal expansion, and the flame-holding cylinder is made of a heat-resistant ferrite metal with a small thermal expansion. It was formed.

Effects According to the present invention, the flame is formed on the outer periphery of the flame-holding tube in the form of a wire mesh, using the above-described configuration. Then, this combustion is carried out in a portion of the burner body corresponding to a plurality of pores with a high flame hole load, and in the remaining portion, combustion is carried out in close contact with the wire mesh with a low flame hole load.

In addition, the burner body is made of a heat-resistant austenitic metal with a large thermal expansion, and the flame-holding tube is made of a heat-resistant ferrite metal with a small thermal expansion, so the diameter of the burner body becomes larger than the diameter of the flame-holding tube at high temperatures. The flame-holding tube always comes into close contact with the burner body, and since ferritic metals have better thermal conductivity than heat-resistant austenitic metals, the heat in the flame-holding tube has a large heat capacity and always flows through it. It is absorbed by the burner body, which is cooled by the mixed vaporized gas, and does not reach extremely high temperatures.
Combustion under stable conditions can be obtained.

Embodiment A combustion appliance according to an embodiment of the present invention will be described below with reference to the drawings. The same parts as in the conventional example will be denoted by the same numbers, detailed explanations will be omitted, and only different parts will be explained.

In FIGS. 1 and 2, the burner head portion 16
1 is a burner body 161a made of austenitic stainless steel with a large thermal expansion, and a flame-holding wire mesh made of ferritic stainless steel with a small thermal expansion stretched over the outer peripheral surface of the burner body 161 so as to cover the pores 162 on the side walls of the burner body. Cylinder 161
It consists of b.

With the above-mentioned configuration, the flame is controlled by the wire-mesh-like flame-holding cylinder 1.
61b. Then, the combustion is carried out in the central part corresponding to the plurality of pores 162 of the burner body 161a, with a large amount of combustion with a high flame hole load, and in the remaining part (periphery of the pores) with a low combustion amount with a low flame hole load. Burning is carried out in close contact with the wire mesh. The former fuel with a high flame hole load has a high ejection speed of combustion vaporized gas and tends to burn away from the flame stabilizing tube 161b, but the latter fuel with a low flame hole load in the vicinity sticks closely to the flame stabilizing tube 161b. Therefore, it is easier to burn in close contact with the flame-holding cylinder 161b. Therefore, it is possible to reduce lift combustion in which the flame is separated from the flame hole and easily generate noise, odor, and carbon monoxide, and it is possible to widen the combustion width.

However, when the flame burns too closely to the wire-mesh-like flame-stabilizing tube 161b, the flame-stabilizing tube 161b itself becomes red-hot, the combustion speed increases, and the flame shortens and becomes too close to the flame-stabilizing tube 161b, causing the flame-stabilizing tube 161b itself to become red hot. This has the additive effect of further increasing the temperature of At this time, if the temperature of the flame-holding cylinder 161b itself becomes too high, the flame-holding cylinder 161b deteriorates and floats above the burner body 161a and breaks, or the wire diameter of the wire mesh becomes thinner. Once again, from burner body 161a, flame-holding cylinder 1
When 61b floats locally, that part becomes even hotter and becomes more red-hot, and it comes to rise gradually. In this way, if there is a gap between the burner body 161a and the flame-holding cylinder 161b for some reason, such as aging or assembly problems, that part will locally become red hot and become extremely hot, causing deformation. Otherwise, the wire mesh may be damaged, and the flame may be drawn into the burner head from that part, causing backfire combustion. However, in the present invention, the material of the burner body 161a is selected from about 30% of the material of the flame-holding cylinder 161b made of ferrite stainless steel with small thermal expansion.
Austenitic stainless steel with double thermal expansion is used. Therefore, at high temperatures, burna body 16
Since the diameter of 1a is larger than that of flame-holding tube 161b,
The flame-holding cylinder 161b always comes into close contact with the burner body 161a. When the flame-holding tube 161b is in close contact with the burner body 161a, the heat of the flame-holding tube 161b is easily conducted to the burner body.Furthermore, since ferrite metal has better thermal conductivity than heat-resistant austenitic metal, the flame-holding tube 161b is in close contact with the burner body 161a. The heat is absorbed by the burner body, which has a large heat capacity and is cooled by the premixed vaporized gas that constantly flows through it, and the flame-holding tube 161
The temperature of b itself does not become extremely high and is stable. Therefore, it is possible to prevent local deformation and abnormal red heat of the flame stabilizing cylinder 161b due to variations in configuration, aging, etc., and to obtain stable combustion over a long period of time. Incidentally, the flame-holding tube 161b may be made of a flat wire mesh stretched over the pores 162.

Effects of the Invention As described above, the present invention includes a burner head having a plurality of pores in the side wall and a burner body formed of a heat-resistant austenitic metal with large thermal expansion, and a burner body that is stretched to cover the pores in the side wall of the burner body. The flame-holding cylinder is made of a heat-resistant ferrite metal with low thermal expansion, which increases the variable range of combustion amount and provides stable combustion that is highly safe over time. It provides combustion appliances.

[Brief explanation of drawings]

Fig. 1 is a full vertical sectional view of a combustion appliance according to an embodiment of the present invention, Fig. 2 is an exploded perspective view of its burner section, Fig. 3 is an overall sectional view of a conventional combustion appliance, and Fig. 4 is the same. FIG. 5 is an exploded perspective view of the burner section, and FIG. 5 is a plan view of the burner. 2... Carburizer cylinder, 161... Burner head part, 1
61a...burner body, 161b...flame-holding tube,
162...Stomata.

Claims (1)

[Claims] 1. A vaporizer tube that vaporizes liquid fuel, premixes the vaporized gas and combustion air, and supplies the mixture to a combustion section, and a burner head section that is disposed in the vaporization tube and forms the combustion section, and the burner head section consists of a burner body having a plurality of pores in its side wall, and a flame-holding tube in the shape of a wire mesh that is closely attached to the outer periphery of the side wall of the burner body and covers the plurality of pores, and the burner body is made of a heat-resistant austenitic metal, The flame-holding cylinder is a liquid fuel combustion device made of heat-resistant ferrite metal.