JPH0136004B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a combustion device mainly used in household heating equipment and the like.

Structure of a conventional example and its problems A general example of a conventional combustion device is shown in FIG.
In FIG. 1, 1 is a vaporized body, which is preheated by an electric heater 2. 3 is a mixing plate, 4 is a flame hole body having a large number of slits, and 5 is a flame in premix combustion. 6 is an outer cylinder, 7 is a primary air blast pipe, 8 is a pipe, and 9 is a fuel pump. 10 is a secondary air blower pipe, and 11 is a blower. Reference numeral 12 denotes a cylinder that guides the exhaust gas to the top, and a purification catalyst 13 having a large number of small holes 14 is installed at the top end of the cylinder.

In this type of combustion device, the fuel discharged from the pipe 8 hits the side wall of the vaporizer 1 facing the pipe 8, flows to the bottom, and is vaporized there.
During steady combustion, the vaporized body 1 is heated by heat conduction from the flame hole body 4 to the vaporized body 1 and a part of the flame 5 is applied to the upper end of the vaporized body 1, and the electricity to the electric heater 2 is reduced as much as possible. I'm trying to reduce it.

However, as can be seen from FIG. 1, it is necessary to receive heat from the flame 5 and the flame hole body 4 at the tip of the vaporizer 1, and to conduct this heat to the bottom via the side wall.
The tip of the vaporized body 1 is caused by a time delay in heat conduction from the top to the bottom of the vaporized body 1, cooling of the bottom of the vaporized body 1 by liquid fuel and primary air, and heat radiation from the outer surface of the vaporized body 1. There is no choice but to create a large temperature difference at the bottom. These factors tend to cause deformation and material deterioration due to non-uniform expansion. Furthermore, although the bottom part vaporizes most of the liquid fuel, the temperature of the vaporized body 1 is the lowest, making it impossible to obtain a stable vaporization state and generating a large amount of tar. Furthermore, in order to maintain the temperature at the bottom of the vaporized body 1 at a constant temperature, it is necessary to control the supply of electricity to the electric heater 2, which results in a large amount of power consumption, which also poses a problem in economical efficiency during use.

Purpose of the Invention The present invention aims to solve such conventional problems, and aims to effectively heat the bottom wall of the vaporizer, which contributes most to the vaporization of liquid fuel, with combustion exhaust gas, thereby stabilizing the gasification process without generating tar. The purpose is to achieve high vaporization and power saving, and also to improve durability by keeping the entire vaporized body at a uniform temperature.

Structure of the Invention In order to achieve this object, the present invention forms an exhaust gas passage so that the exhaust gas from the combustion section flows in contact with the side wall and the bottom wall of the vaporizer, and the exhaust gas passage faces the bottom wall of the vaporizer. A discharge port for the gas passage is provided, and a radiator heated by the exhaust gas is installed here. Thereby, the heat necessary for vaporization can be effectively fed back to the bottom through heat exchange from the combustion exhaust gas and radiation conduction from the radiator. Furthermore, the entire vaporized body can be maintained at a uniform temperature optimal for vaporization, and exhaust gas can also be purified by supporting a platinum catalyst or the like on the radiator.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

Reference numeral 15 denotes a cylindrical vaporizer with a bottom, which is preheated by an electric heater 16 . 17 is the bottom wall of the vaporizer 15, and 18 is a mixing plate.

Reference numeral 19 denotes an outer cylinder, and a discharge port 20 for exhaust gas is provided at the lower part. 21 indicates an exhaust gas passage. 2
2 is a blower pipe, and 23 is a blower. 24 is a pipe, and 25 is a pump for supplying liquid fuel. 26
A combustion body 28 made of a wire mesh or the like is located outside the flow regulating body having a large number of small holes 27, and one end of the combustion body 28 is connected to the upper end of the vaporization body 15. 29
is an outer plate made of heat-resistant glass or the like and placed on the outer cylinder 19. 30 is a cap. 31
3 is a radiator having a ventilation hole 32, and 33 is a holding fitting.

The operation in the above configuration will be explained.

First, the electric heater 16 is energized, and the vaporized body 15 is
Preheat to 300℃. Next, the blower 23 and the pump 25
When energized, combustion air and fuel necessary for complete combustion are supplied into the vaporizer 15, and the fuel vaporizes to become a premixed gas with air. This premixed gas enters the rectifier 26 from the center of the mixing plate 18, and enters the small hole 27.
It is ejected onto the outer surface of the combustion body 28, where it is ignited and combusted. The combustion flame is formed in a thin layer on the outer surface of the combustion body 28, and combustion is completed here, and the combustion body 28 itself becomes red-hot to about 850° C. and radiates radiant heat through the outer plate 29. On the other hand, the combustion exhaust gas travels between the combustion body 28 and the outer plate 29, between the side wall of the vaporization body 15 and the outer cylinder 19, and then passes through the passage 21 provided below the bottom wall of the vaporization body 15 to the discharge port 20. It is discharged through a radiator 31 installed in the section.

In the process of combustion exhaust gas flowing, vaporized body 15
The electric heater 16 receives sufficient heat on the side walls and bottom of the
Even if the electricity is cut off, the fuel can be continuously vaporized only by the feedback of combustion heat. In particular, the bottom of the vaporizer 15 is intensively heated by exhaust gas and radiant heat from the radiator 31 and can maintain a high temperature, so that stable vaporization and tar generation can be suppressed.

Effects of the Invention The present invention provides the following effects by forming an exhaust gas passage below the bottom of the vaporizer, providing an exhaust gas discharge port at a position facing the bottom wall, and installing a radiator here. have an effect.

(1) The bottom wall of the vaporizer, which vaporizes most of the fuel, is heated in a concentrated manner by the combustion exhaust gas and radiant heat from the radiant, which becomes red-hot to constantly maintain the high temperature state optimal for vaporization. This increases the vaporization rate, provides a stable vaporization state without vaporization pulsation, and greatly suppresses the generation of tar.

(2) During steady combustion, the bottom wall of the vaporized body is heated in a concentrated manner, and heat is received from all of the outer surface of the body, so the vaporized body itself can be maintained at a high and uniform temperature. Therefore, there is no local overheating, no deformation due to non-uniform thermal expansion, and durability is improved.

(3) Conventionally, it took time for heat to be conducted from the heat receiving part to the wall surface where the fuel is vaporized, but in the present invention, the exhaust gas reaches the fixed part of the vaporized material immediately after combustion starts, and heats it. Power to the electric heater can also be turned off immediately, resulting in power savings and stable vaporization.

(4) By supporting a catalyst such as platinum on the radiator, CO, HC, etc. in the exhaust gas can be purified, resulting in a cleaner combustion device. In particular, after extinguishing the fire, the radiant body is heated by the radiant heat from the bottom wall of the vaporized body, making it possible to extend the purification time.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing a conventional combustion apparatus, and FIG. 2 is a side sectional view of a combustion apparatus according to an embodiment of the present invention. 15... vaporized body, 17... bottom wall, 21... passage, 31... radiator.

Claims (1)

[Claims] 1. A combustion section is connected to a bottomed cylindrical vaporizer that is preheated by an electric heater, and communicates with the exhaust gas outflow side of the combustion section, so that the exhaust gas flows from the side wall to the bottom wall of the vaporizer. A combustion device in which a gas passage is formed, a discharge port of the gas passage is provided opposite to the bottom wall of a vaporizer, and a radiator heated by exhaust gas is provided at the discharge port.