JPH06265113A - Liquid fuel combustion device - Google Patents

Abstract

PURPOSE:To provide a stable combustion flame under a weak combustion by a method wherein a mesh part of low heat transfer rate is arranged at a bottom part within a gasification cylinder, an independent cage is placed between the extremity end of a needle pipe and the mesh part and then the needle pipe and the mesh part are connected to the cage part. CONSTITUTION:A mesh part 28 is mounted at a bottom part of a gasification cylinder 1 to which liquid fuel drips. The mesh part 28 is made of material having a low heat transfer rate. An independent cage 29 is applied to connect the extremity end of the needle pipe 8 supplying liquid fuel and the mesh part 28 arranged between it and the bottom part of the gasification cylinder 1. This cage has a substantial L-shape to cause the liquid fuel to be flowed down to the bottom part of the gasification cylinder 1. With such an arrangement as above, it is possible to restrict pulsation of gasification at the weak combustion and to generate a stable combustion flame.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid fuel combustion apparatus in which liquid fuel is vaporized, mixed with combustion air and sent to a burner head where it is ignited and burned. The present invention relates to a liquid fuel combustion apparatus that sometimes suppresses vaporization pulsation of liquid fuel to generate stable combustion flames and maintains weak combustion.

[0002]

2. Description of the Related Art FIG. 5 is a vertical sectional view showing an example of the vicinity of a combustion section of a conventional liquid fuel combustion apparatus. Reference numeral 1 is a vaporization tube that vaporizes liquid fuel and mixes it with combustion air to produce a combustible gas mixture. Reference numeral 2 is an electric heater embedded in the side wall of the vaporization tube 1. Reference numeral 3 denotes a burner head which is placed on the upper portion of the vaporization cylinder 1 to form a combustion flame, 4 denotes a plurality of flame holes provided in the burner head 3, and 5 denotes a wire net tightly wound around the outer peripheral surface of the burner head 3. .

Reference numeral 6 is an annular flame holding ring provided around the burner head 3 to prevent the spread of the flame and to protect the combustion flame from disturbance. Reference numeral 7 is a nozzle portion for sending combustion air into the vaporization cylinder 1, and 8 is a needle pipe provided in the longitudinal direction of the central portion of the nozzle portion 7, for feeding liquid fuel into the vaporization cylinder 1. Reference numeral 9 denotes a throttle portion attached to the upper portion of the vaporization cylinder 1, and 10 denotes a mixing plate attached to the upper portion of the throttle portion 9 inside the burner head 3. Reference numerals 11 and 12 denote a primary combustion flame and a secondary combustion flame ignited by an ignition means (not shown) such as a discharge spark.

Next, the operation of the liquid fuel combustion apparatus configured as described above will be described. First, when a power switch (not shown) is turned on to energize the electric heater 2, the vaporization cylinder 1 is preheated to a temperature (about 250 ° C. to 300 ° C.) necessary for vaporizing the fuel. The temperature of the vaporizing cylinder 1 at this time is detected by a thermostat (not shown), and the power is turned on and off.
To be done. When the preheating is completed in this way, the combustion air is sent from the nozzle portion 7 into the vaporization cylinder 1, and the liquid fuel is extruded in a mist form from the needle pipe 8 by the blowing pressure of the combustion air. In this way, the fuel and the air have a predetermined ratio in the vaporization cylinder 1.

The fuel sent into the vaporization cylinder 1 is vaporized into the vaporization cylinder 1.
It is vaporized by the heat inside and mixes with combustion air to produce a combustible gas mixture. Then, it is sent to the burner head 3 through the narrowing portion 9 and the mixing plate 10, is rectified there, passes through the flame holes 4 and the wire mesh 5, is jetted at a predetermined jet pressure, and is ignited by an ignition means such as a discharge spark. Then, the primary combustion flame 11
And the secondary combustion flame 12.

In the conventional liquid fuel combustion apparatus configured as described above, the blowing pressure of the combustion air fed from the nozzle portion 7 into the vaporization cylinder 1 is weakened during weak combustion. For this reason,
Since the liquid fuel extruded from the needle pipe 8 is not atomized, it is not ejected in the form of mist and becomes an oil drop that drops to the bottom of the vaporization cylinder 1. Since the interval at which the liquid fuel is dropped is large and the bottom of the vaporization cylinder 1 is high in temperature, it vaporizes instantly and causes vaporization pulsation when dropped. Therefore, there is a problem that the combustion flame is not stable and a wide combustion width cannot be obtained.

FIG. 6 shows, for example, the Japanese Utility Model Laid-Open No. 55-153410.
7 is a longitudinal sectional view showing an example of the combustor disclosed in Japanese Patent Publication No.
FIG. 6 is a vertical sectional view showing another example of a combustor. As shown in the figure, kerosene 13 is atomized by a nozzle 14 and its particles 15
Is heated on the evaporation surfaces 17 (FIG. 6) and 18 (FIG. 7) of the vaporizer 16 to be vaporized and burned. The evaporation surfaces 17 and 18 are provided with grid-like grooves 19 (FIG. 6), or a metal net 20 having excellent heat resistance such as stainless steel.
(Fig. 7) is in close contact, so the particles 15 are
Since particles 15 do not fly over 7, 18 and bond growth between particles 15 is prevented and the evaporation area becomes large, particles 15
The stable flame 21
Is obtained.

However, in the above example, the particles 15 of the kerosene 13 atomized and scattered by the nozzle 14 evaporate on the evaporation surfaces 17, 1.
8 is to prevent the bond growth of the particles 15 when they drop to the top and boil, thus preventing the liquid fuel from dropping from the needle pipe at regular intervals and instantaneously vaporizing during weak combustion. This is not for solving the problem shown in FIG.

FIG. 8 is a longitudinal sectional view showing an example of the liquid fuel combustion apparatus disclosed in, for example, Japanese Utility Model Laid-Open No. 55-60011. As shown in the figure, this device has a plurality of linear metal members 23 fixed to the tip of the oil feed pipe 22, the other end of which is brought into contact with the bottom surface of the vaporization chamber 24, and the linear metal members 23 are arranged at appropriate intervals. It is arranged so that the fuel is uniformly supplied to the entire bottom surface 25 of the vaporization chamber. And blower 2
When 6 rotates and the combustion air is sent into the vaporization chamber 24, a fuel cutoff valve (not shown) is opened and the supply of liquid fuel from the transport pipe 22 is started. The vaporization of the liquid fuel is performed by the heating element 27 located on the bottom surface of the vaporization chamber 24.

[0010]

The above liquid fuel combustion apparatus (FIG. 8) is different from the liquid fuel combustion apparatus shown in FIG. 5 in its structure. That is, it is different from the configuration shown in FIG. 5 in which the liquid fuel in the needle pipe located in the nozzle portion is extruded in a mist state by the blowing pressure by the nozzle portion, and it naturally occurs from the configuration shown in FIG. The device of FIG. 8 does not solve the problem, that is, the problem that the liquid fuel does not eject in a mist state at the time of weak combustion and drops to cause vaporization pulsation.

The present invention has been made to solve the above problems, and it is possible to generate a stable combustion flame without causing vaporization pulsation even when the liquid fuel does not eject in a mist state during weak combustion. An object of the present invention is to obtain a liquid fuel combustion device capable of

[0012]

In the liquid fuel combustion apparatus according to the present invention, a mesh portion having a low thermal conductivity is provided at the bottom of the vaporization cylinder, and an independent portion is provided between the tip portion of the needle pipe and the mesh portion. A blind part is provided, and the needle pipe and the mesh part are connected by this blind part.

In the liquid fuel combustion apparatus according to the present invention, a mesh portion having a low thermal conductivity is provided at the bottom of the vaporization cylinder, and a blind portion integrally formed with the needle pipe is provided at the tip of the needle pipe. The needle pipe and the mesh part are connected by the blind part.

Further, in the liquid fuel combustion apparatus according to the present invention, a mesh portion having a low thermal conductivity is provided at the bottom of the vaporization cylinder, and the tip portion of the needle pipe is bent to form a blind portion. The needle pipe and the mesh portion are connected by.

Further, in the liquid fuel combustion apparatus according to the present invention, a mesh portion having a low thermal conductivity is provided at the bottom of the vaporizing cylinder, and the mesh portion is integrally formed between the tip portion of the needle pipe and the mesh portion. A blind part is provided, and the needle pipe and the mesh part are connected by this blind part.

[0016]

[Operation] At the time of weak combustion, the liquid fuel flows from the needle pipe through the blind part to the mesh part provided in the bottom part of the vaporization cylinder,
Here, the vapor pulsation is suppressed to gradually vaporize, and a stable combustion flame is generated.

[0017]

【Example】

Embodiment 1 FIG. 1 is a vertical sectional view showing a first embodiment of the present invention. The same parts as those in the conventional example of FIG. 5 are designated by the same reference numerals and the description thereof will be omitted. Reference numeral 28 denotes a mesh portion installed at the bottom of the vaporization cylinder 1 where the liquid fuel drops, and is made of a material having a low thermal conductivity. Reference numeral 29 denotes an independent blind portion that connects the tip portion of the needle pipe 8 for supplying the liquid fuel and the mesh portion 13 installed between the bottom portion of the vaporization cylinder 1 and has an approximately L shape, and is a liquid fuel. It is made to flow down to the bottom of the vaporization cylinder 1.

Next, the operation of the present invention constructed as above will be described. Since the combustion process of the liquid fuel combustion device is the same as that shown in the conventional example (FIG. 5), its description is omitted. When the liquid fuel becomes weakly burned when it is burned, the blowing pressure of the combustion air is weakened, and the liquid fuel may not be jetted from the needle pipe 8. At this time, since the needle pipe 8 and the mesh portion 28 are connected by the blind portion 29, the liquid fuel flows down to the mesh portion 28 through the blind portion 29. Since the mesh portion 28 has a lower thermal conductivity and a lower temperature than the bottom portion of the vaporization cylinder 1, the liquid fuel dropped on the mesh portion 28 is gradually vaporized with a delay in vaporization. Therefore, the first
According to the embodiment described above, the liquid fuel does not drip from the needle pipe 8 to the bottom of the vaporization cylinder 1 and does not vaporize instantly, so vaporization pulsation during weak combustion is suppressed, and a stable combustion flame is obtained. To generate.

Embodiment 2 FIG. 2 is a vertical sectional view showing a second embodiment of the present invention. Three
0 is the tip of the needle pipe 8 for supplying liquid fuel,
A blind part that connects between the mesh part 13 installed at the bottom of the vaporization cylinder 1 and is integrally molded with the needle pipe 8 so that the liquid fuel flows down to the bottom of the vaporization cylinder 1. According to the second embodiment, it is possible to suppress the vaporization pulsation during weak combustion to generate a stable combustion flame and reduce the number of parts to improve the assemblability.

Embodiment 3 FIG. 3 is a vertical sectional view showing a third embodiment of the present invention. 8
Reference numeral a denotes a blind portion in which the tip of the needle pipe 8 is bent and bent, and the tip is connected to the mesh portion 28 installed at the bottom of the vaporization tube 1 to allow liquid fuel to flow to the bottom of the vaporization tube 1. Let it flow down. According to the third embodiment, it is possible to suppress the vaporization pulsation during weak combustion to generate a stable combustion flame, reduce the number of parts, and improve the assemblability.

Embodiment 4 FIG. 4 is a vertical sectional view showing a fourth embodiment of the present invention. Two
Reference numeral 8a denotes a blind portion that connects the tip end portion of the needle pipe 8 that supplies the liquid fuel and the mesh portion 13 installed at the bottom portion of the vaporization cylinder 1, and is formed of a mesh, and is substantially integrally formed with the mesh portion 13 Liquid fuel vaporization cylinder 1 with S-shape
Let flow down to the bottom. According to the fourth embodiment, it is possible to suppress the vaporization pulsation during weak combustion to generate a stable combustion flame, reduce the number of parts, and improve the assemblability.

[0022]

As is apparent from the above description, the liquid fuel combustion apparatus according to the present invention comprises a needle pipe for feeding the liquid fuel, a mesh portion installed at the bottom of the inside of the vaporizing cylinder and vaporizing during weak combustion. Since they are connected by a blind, it is possible to suppress the vaporization pulsation during weak combustion and generate a stable combustion flame, and it is possible to obtain a wider combustion variable width than before. In addition, the number of parts can be reduced by integrally molding the needle pipe and the blind part (Fig. 2), the mesh part and the blind part (Fig. 4), or by forming the blind part (Fig. 3) by bending the needle pipe. It is possible to improve the assemblability and reduce the manufacturing cost.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a first embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view showing a second embodiment of the present invention.

FIG. 3 is a vertical sectional view showing a third embodiment of the present invention.

FIG. 4 is a vertical sectional view showing a fourth embodiment of the present invention.

FIG. 5 is a vertical sectional view showing an example of a conventional liquid fuel combustion apparatus.

FIG. 6 is a vertical sectional view showing an example of a conventional combustor.

FIG. 7 is a vertical cross-sectional view showing another example of a conventional combustor.

FIG. 8 is a vertical sectional view showing an example of a conventional liquid fuel combustion apparatus.

[Explanation of symbols]

 1 vaporization cylinder 3 burner head 7 nozzle 8 needle pipe 8a, 28a, 29, 30 blind part 28 mesh part

Claims (4)

[Claims] 1. A vaporization cylinder that vaporizes liquid fuel and mixes it with combustion air to produce a combustible gas mixture; a nozzle section for forcibly supplying combustion air into the vaporization cylinder; and a nozzle section provided in the nozzle section. A liquid fuel combustion apparatus comprising a needle pipe for feeding liquid fuel into the vaporization cylinder, and a burner head having a flame holding ring or the like for forming combustion flame on the upper portion of the vaporization cylinder, wherein a bottom portion in the vaporization cylinder In addition to providing a low thermal conductivity mesh portion in the, a separate blind portion is provided between the tip portion of the needle pipe and the mesh portion, the needle pipe and the mesh portion are connected by the blind portion. A liquid fuel combustion apparatus characterized by the following. 2. A vaporization cylinder that vaporizes liquid fuel and mixes it with combustion air to generate a combustible mixed gas, a nozzle section for forcibly supplying combustion air into the vaporization cylinder, and a nozzle section provided in the nozzle section. A liquid fuel combustion apparatus comprising a needle pipe for feeding liquid fuel into the vaporization cylinder, and a burner head having a flame holding ring or the like for forming combustion flame on the upper portion of the vaporization cylinder, wherein a bottom portion in the vaporization cylinder In addition to providing a low thermal conductivity mesh portion to the needle pipe, a needle portion integrally formed with the needle pipe is provided at the tip of the needle pipe, and the needle pipe and the mesh portion are connected by the blind portion. Fuel combustion device. 3. A vaporization cylinder that vaporizes liquid fuel and mixes it with combustion air to generate a combustible mixed gas, a nozzle section for forcibly supplying combustion air into the vaporization cylinder, and a nozzle section provided in the nozzle section. A liquid fuel combustion apparatus comprising a needle pipe for feeding liquid fuel into the vaporization cylinder, and a burner head having a flame holding ring or the like for forming combustion flame on the upper portion of the vaporization cylinder, wherein a bottom portion in the vaporization cylinder In addition to providing a mesh portion having a low thermal conductivity to, the tip portion of the needle pipe is bent to form a blind portion, and the needle pipe and the mesh portion are connected by the blind portion. Combustion device. 4. A vaporization cylinder that vaporizes liquid fuel and mixes it with combustion air to produce a combustible mixed gas, a nozzle section for forcibly supplying combustion air into the vaporization cylinder, and a nozzle section provided in the nozzle section. A liquid fuel combustion apparatus comprising a needle pipe for feeding liquid fuel into the vaporization cylinder, and a burner head having a flame holding ring or the like for forming combustion flame on the upper portion of the vaporization cylinder, wherein a bottom portion in the vaporization cylinder While providing a low thermal conductivity mesh portion in the, provided a blind portion integrally molded with the mesh portion between the tip portion of the needle pipe and the mesh portion, the needle pipe and the mesh portion by the blind portion. A liquid fuel combustion device characterized by being connected.