JPS6333610B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid fuel combustion device that uses fuel atomized by ultrasonic waves, and more particularly to a liquid fuel combustion device that allows combustion amount to be controlled over a wide range.

Conventionally, the amount of combustion in this type of combustion device was controlled by controlling the input to an ultrasonic vibrator attached to the bottom of the atomization tank and correspondingly adjusting the amount of primary air. . However, this method has the disadvantage that the control mechanism becomes complicated and expensive. It is also conceivable to control the rotation speed of the blower motor in order to control the amount of primary air continuously or stepwise, but such a control means is expensive and therefore difficult to adopt.

Furthermore, the flame in conventional combustion devices that burn atomized fuel is usually a diffusion flame, but since the diffusion flame is difficult to mix with air, the completion of complete combustion is delayed and the flame tends to be long and red. As a result, the shape (height) of the combustion chamber becomes high, which poses a problem in that the degree of freedom in designing the combustion device is reduced. Red flames also have the disadvantage of producing large amounts of nitrogen oxides due to their high temperatures.

This invention was made to solve the above-mentioned problems, and it is possible to easily control the combustion amount over a wide range with a relatively simple configuration, and also to suppress the height of the flame and reduce the height of the combustion chamber. It is an object of the present invention to provide a liquid fuel combustion device that can generate less nitrogen oxides.

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, numeral 1 is an atomized fuel generator equipped with a plurality of ultrasonic vibrators 3 at the bottom of an atomization tank 2. A fixed amount of fuel is supplied. The ultrasonic transducer 3 is connected to the output end of the ultrasonic oscillator 6, thereby supplying ultrasonic energy.

7 is a blower, whose air passage is branched into two,
One side is connected to the atomization tank 2 via the primary air supply pipe 8.
and the other to the combustor 10 via the secondary air supply pipe 9.
The guide paths 11 are connected to each other. A valve mechanism 12 is provided in the middle of the primary air supply pipe 8, which is a particularly important component in the present invention. In addition, the atomization tank 2 is connected to the combustor 1 by the atomization fuel supply pipe 13.
0 combustion chamber 14. In the figure, 15 is the combustor outer box, 16 is the combustion tube, 17 is the convection fan, 1
8 indicates a flame.

Next, details of the combustor 2 will be explained with reference to FIG.
FIG. 2 is an enlarged view of FIG. 1 taken along the - line section and viewed in the direction of the arrow. A combustor inner case 19 is provided inside the combustor outer case 15 so as to form the aforementioned secondary air guide path 11 . The atomized fuel supply pipe 13 is provided at the center of the bottom plate 20 of the combustor inner box 19 so as to divide the bottom plate 20 into two, and a heating bottom plate 21 having a protruding shape of the combustion chamber 14 is provided above the supply pipe 13.
is provided to constitute a heater, and a guide plate 22 following this forms an atomized fuel guide path 23. The guide path 23 is configured to form a closed circuit with the combustion chamber 14 via a pair of porous combustion plates 24. The pair of porous combustion plates 24 are linear and symmetrically arranged to generate split flames.

The supply pipe 13 has a plurality of atomized fuel discharge holes 2.
5 is provided, and the atomized fuel discharged from the discharge hole 25 is heated by the heating bottom plate 21 at the top, passes through the guide path 23, and reaches the porous combustion plate 24. Further, secondary air necessary for combustion is supplied from the secondary air supply pipe 9 provided at the bottom of the combustor outer case 15 to the guide path 11 formed by the combustor outer case 15 and the combustor inner case 19. A part of the secondary air passes through the branch guide path 26 to the first air chamber 27a provided at the bottom of the porous combustion plate 24, and another part of the secondary air goes to the second air chamber 27a provided at the bottom of the porous combustion plate 24. The air is guided to a second air chamber 27b provided at the upper part of the porous combustion plate 24 through a hole 28 provided at the end of the secondary air guide path 11.

The combustion chamber 14 is formed by part of the wall surfaces of the first air chamber 27a and the second air chamber 27b. In addition, a plurality of first air circulation holes 29 from the first air chamber 27a, a plurality of first air circulation holes 29 from the first air chamber 27a, and a plurality of first air circulation holes 29 from the first air chamber 27a, the second air chamber 27b
A second air circulation hole 30 is provided from each side to constitute a secondary air supply means. These first and second air circulation holes 29 and 30 are designed to distribute secondary air in the same direction as the atomized fuel discharged from the porous combustion plate 24 (in the horizontal direction in FIG. 2). In the case of the first air circulation hole 29, the upper horizontal wall surface of the first air chamber 27a is provided, and in the case of the second air circulation hole 30, the inclined wall surface of the lower side wall of the second air chamber 27b is provided so as to prevent the air from being discharged. Each is provided. By doing so, secondary air is supplied to the divided flames generated from the pair of porous combustion plates 24 from both sides of each flame.

In FIG. 2, reference numeral 31 denotes a combustor lid forming the upper wall of the second air chamber 27b. A flame port 32 is formed in the center of the combustor lid, and the above-mentioned combustion tube 16 is provided on the upper part of this lid.

Next, the operation of this combustion device will be explained. A fixed amount of liquid fuel from the fuel tank 4 is supplied to the atomized fuel generator 1 via the oil level regulator 5, and is atomized by the action of a plurality of ultrasonic vibrators.

This atomized fuel is supplied from the blower 7 to the primary air supply pipe 8
The primary air sent through the atomized fuel supply pipe 13 enters the combustion chamber 14 through the atomized fuel discharge hole 25.
It is discharged toward the heating bottom plate 21 at the bottom. The atomized fuel is rectified by this bottom plate 21 and flows through the guide path 23.
is supplied to the combustion chamber 14 via the porous combustion plate 24.
The light is ignited by a spark plug (not shown).

The ignited flame receives lower secondary air supplied from the blower 7 through the secondary air supply pipe 9, the guide path 11, the branch guide path 26, the first air chamber 27a, and the first air circulation hole 29, and the guide passage 11, second air chamber 27
(b) The upper secondary air supplied through the second air circulation hole 30 is mixed with the upper secondary air, and sufficient combustion is carried out.

After combustion starts, part of the combustion heat is recovered and the protruding heating bottom plate 21 becomes high temperature, so the atomized fuel discharge hole 2
The atomized fuel discharged from the combustion chamber 5 is heated to a sufficiently high temperature in this region and is led to the combustion chamber 14 without fear of condensation.

In this combustion apparatus, the thermal power of the combustion chamber 10 is controlled by adjusting the amount of primary air supplied to the atomized fuel generator 1 using a valve mechanism 12 provided in the primary air supply pipe 8. That is, since the amount of atomized fuel supplied from the atomized fuel generator 1 to the combustor 10 is proportional to the amount of this primary air, the valve mechanism 12
By controlling the amount of primary air, the amount of combustion can be controlled continuously or in stages.

Further, the extinguishing of the combustion device can be automatically performed by stopping the supply of ultrasonic energy to the ultrasonic vibrator 3 and stopping the generation of atomized fuel in the atomized fuel generating device 1.

In this combustion device, the atomized fuel is heated to a heater such as a heating bottom plate and is supplied in a state where it is difficult to condense, so there is no time delay when extinguishing a fire, and instant fire extinguishment is possible. Since stable atomized fuel can always be supplied to the combustion chamber, stable combustion can be performed. In particular, in this invention, a pair of linear porous combustion plates are arranged symmetrically to form split flames, and secondary air is supplied to the split flames from both sides of each flame. Therefore, the supply of secondary air is sufficient and complete combustion is achieved quickly, so that the split flame can be made into a short blue flame.

Therefore, it is possible to reduce the shape (height) of the combustion chamber, and the degree of freedom in design can be improved.

Furthermore, since the blue flame has a low temperature, the generation of nitrogen oxides can be reduced, making it possible to use a sanitary combustion device.

The mounting position of the valve mechanism, which is a feature of this invention, is as follows:
It is also possible to install it in the atomized fuel supply pipe between the atomized fuel generator and the combustor, but if this is done, the condensed atomized fuel will adhere to the inside of the valve mechanism, making it impossible to supply a stable atomized fuel. In addition, there is a risk that liquefied fuel may leak from the valve mechanism to the outside. Therefore, it is appropriate to provide it between the blower and the atomized fuel generator as in the present invention.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of the present invention, and FIG. 2 is an enlarged view of FIG. 1 taken along the line ``-'' and viewed in the direction of the arrow. 1...Atomized fuel generator, 2...Atomization tank, 3...
...Ultrasonic vibrator, 4...Fuel tank, 5...Oil level regulator, 6...Ultrasonic oscillator, 7...Blower, 8
...Primary air supply pipe, 9...Secondary air supply pipe, 1
0... Combustor, 11... Guide path, 12... Valve mechanism, 13... Atomized fuel supply pipe, 14... Combustion chamber,
15... Fuel container outer box, 16... Combustion cylinder, 17...
Convection fan, 18...Flame, 19...Combustor inner box, 20...Bottom plate, 21...Heating bottom plate, 22...
...Guide plate, 23...Guide path, 24...Porous combustion plate, 25...Discharge hole, 26...Branch guide path, 27
a...First air chamber, 27b...Second air chamber, 28
... hole, 29 ... first air circulation hole, 30 ... second air circulation hole, 31 ... combustor lid, 32 ... flame port.

Claims (1)

[Claims] 1. An atomized fuel generator that atomizes the liquid fuel stored at the bottom of the atomization tank by ultrasonic vibration, and 1. a combustion chamber supplied through a pair of porous combustion plates; a blower for supplying primary air into the atomized fuel generator and secondary air within the combustion chamber; the blower and the mist; a valve mechanism for controlling primary air provided in the middle of a primary air supply pipe connecting between the fuel generating devices;
A liquid fuel combustion apparatus comprising: secondary air supply means for supplying secondary air from both sides of each flame from the blower to the divided flames generated from the pair of porous combustion plates.