JPS6131808A - Liquid fuel combustion equipment - Google Patents

Abstract

PURPOSE:To maintain a constant level of combustion load at a flame hole and stabilize the flame by a method wherein another combustion section is provided in downstream of the flame generated in a combustion section, thereby switching the flame area in correspondence with a varible fuel combustion volume. CONSTITUTION:The combustion sections 16a and 16b are arranged closely together and in the downstream of the combustion gas discharged from the combustion section 16a the combustion section 16b is provided. When supplying electricity to a heater 4 of carbureter 1, driving blower 7, and driving a fuel pump 9, the vaporized fuel gas is mixed with fresh air for combustion, and flows out through a metal screen covering the surfaces around the combustion section 16a, 16b, thereafter said gas is ignited by an ignitor in a combustion space 18 positioned between an outer casing 19 and combustion sections, and forms the combustion flame on the surface of the metal screen. When the combustion volume is greater an open/close valve 12 is opened and requied volume of fuel and air equivalent to the combustion volume are supplied to evaporation chambers to burn over the whole area of metal screens covering the section 16a, 16b, 3a, 3b. When the combustion volume is smaller, the valve 12 is closed, the fuel is supplied from the vaporizer 3 only to the combustion section 16a.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a liquid fuel combustion device that evaporates liquid fuel and burns gas premixed with air at a flame nozzle.

Conventional structure and its problems Conventionally, this type of liquid fuel combustion device has a heater embedded in the lower part of the vaporizer, and a ventilation passage connected to the blower on the side wall of the vaporizer and a fuel capillary with a nozzle-shaped tip. It is possible to connect it to a fuel pump.

A combustion section having a flame port is connected to the vaporizer. Fuel is supplied from the tank by the combustion pump to the vaporizer through the fuel tube, where it is gasified on the high-temperature wall, mixed with air, and combusted at the flame port of the combustion section.

In this combustion state, the outflow speed of the fuel gas flowing out from the flame port and the combustion speed are balanced at the flame port, and the flame surface is stably held and combustion is sustained. The amount of combustion was controlled by adjusting the blower and fuel pump to increase or decrease the amount of air and fuel flow in response to fluctuations in the heating and other loads. However, since the area of the flame opening in the combustion section is constant, if the combustion amount exceeds a certain level, the flame will lift, producing gas, Co, and odor, and if the combustion amount falls below a certain level, the flame surface will become pale. Because the temperature in the center did not become high enough, a portion of the flame front disappeared, producing gas, CO, and odor. Furthermore, when the ratio of fuel and air changed, in addition to the gas, CO, and odor, the flame approached the flame nozzle and the flame nozzle overheated, causing thermal deformation. As a result, the variable range of combustion amount that can maintain good combustion is limited, and the method of separately providing multiple burners with different combustion amounts is difficult to use due to the timing of combustion switching and the odor generated when igniting and extinguishing.

OBJECTS OF THE INVENTION It is an object of the present invention to widen the variable range of combustion amount by keeping the flame port load constant.

Structure of the Invention The present invention provides a plurality of partitioned vaporization chambers, each of which is provided with a combustion section in communication with the other, and these combustion sections are provided in contact with each other, and another combustion section is arranged in the wake of the flame generated in at least one combustion section. By arranging the flame openings in such positions, it is possible to change the flame opening area according to the increase or decrease in the amount of combustion with good flame propagation, and to stabilize the flame by keeping the flame opening load constant.

Description of examples Hereinafter, an explanation will be given based on one embodiment of the present invention.

In the figure, a bottomed vaporizer 1 is separated into two vaporization chambers 3a and 3b by a partition wall 2, a heater 4 is embedded in the circumferential direction of the side surface, and a mixing plate with a constriction shape is provided on the open surface. 5a and 5b are installed. Furthermore, the wall of the vaporizer 1 is provided with a ventilation passage 6a.

Fuel capillaries 8a and 8b whose tips constitute nozzles together with an air supply means comprising a blower 7 via 6b
The fuel thin tube 8a faces the vaporization chambers 3a and 3b through the ventilation passages 6a and 6b, respectively.

The other end of 8b is connected to a fuel tank 10 via a fuel pump 9 to constitute fuel supply means. Ventilation passage 6b
A constriction part 11 is provided in the middle, and the end thereof is connected to the ventilation passage 6a. A passage opening/closing valve 12 is provided in the middle of the fuel thin tube 8b, and the end thereof is a fuel thin tube.

8a, thereby forming a means for controlling air and fuel. The upper part of the vaporizer 1 has a rectifying cylinder 14a formed in a cylindrical shape and having a large number of pores 13 along the circumferential direction;
14b, and this rectifier cylinder 14a.

Combustion sections 16a and 16b made of wire mesh are provided around the combustion chamber 14b through a rectification space 15a and tab, and the upper end of the combustion section 1611.16)) is closed by a closing plate 17. A closing plate 17 is placed around the combustion parts 16a and 16b.
The outer cylinder 19 is passed through the combustion space 18 whose one end is closed by
The other end of this outer cylinder 19 is covered with a support cylinder 20, and the combustion gas forms a passage through which the combustion gas flows to the outside through a jet port 21 provided in this support cylinder 20. The rectifying tube 14 is separated into two parts by a partition tube 22, and the combustion section 16 is separated from the vaporization chambers 3a and 3b.
a and 16b, the combustion part 16a and the combustion part 16b are provided in contact with each other, and the combustion part 16b is provided in the wake of combustion gas discharged from the combustion part 1[3a.

Next, the operation will be explained. By energizing the heater 4 in the vaporizer 1, the vaporization chamber 3a is created.

3b is heated and the temperature rises. After this, the ventilation passages 6a, 6
Combustion air is introduced into the vaporization chambers 3a and 3b by driving the blower 7 provided through the air blower 7b. Subsequently, the fuel pump 9 is driven to draw fuel from the fuel tank 10, and the fuel is jetted into the vaporization chambers 3a, 3b from the tip nozzles of the fuel thin tubes 8a, 8b. The spouted fuel becomes granular and collides with the walls of the vaporization chambers 3a and 3b, absorbing the heat from the high-temperature walls and becomes vaporized gas.
.

5b and flows to the rectifier tubes 14a, 14b. At this time, the vaporized fuel gas is mixed with combustion air, flows out as a premixture from around the combustion parts 16a and 16b arranged with wire mesh, and is transferred to the outer cylinder 19 and the combustion parts 16a and 1.
6b is ignited by an igniter (not shown) in the combustion space 18, and a combustion flame is formed on the surface of the wire mesh (combustion parts 1ea, 16b). The combustion air sent from the blower 7 is controlled by the throttle section 11 to a ratio corresponding to the combustion sections 16a and jab. Further, the on-off valve 12 controls the flow resistance to control the distribution of the fuel supplied by the fuel pump 9 to the combustion parts 16a and 16b, and controls the supply of fuel to the combustion part 16b to 0N-O.
Performs FF control.

Therefore, fuel and air can be individually controlled and supplied to the combustion sections 16a and jab. That is, when the amount of combustion is large, the on-off valve 12 is opened. Fuel pump supplies fuel and air according to the amount of combustion9. Each vaporization chamber 3a is opened by the blower 7.
, 3b, and the vaporized fuel gas is supplied to the mixing cylinders 5a, 5.
b, rectifier cylinder 14a.

14b and burns in the combustion section 16a and the entire wire mesh of IQb. When the amount of combustion is small, the on-off valve 12 is closed and fuel is supplied only to the combustion section 16a from the vaporization chamber 3a. The amount of fuel and air supplied to the combustion section 16a is the same as when the combustion amount is large, and the flame is formed only in the upper part of the combustion section.

Therefore, when the amount of combustion is large, the area of the flame port made up of the combustion part is large, and when the amount of combustion is small, the area of the flame port is small.

That is, the flame outlet load becomes a constant value, and the outflow velocity can be stably maintained at a rate corresponding to the combustion rate. For this reason, the flame does not cause lifting due to an increase in the outflow speed, and
Due to the slow outflow speed, there will be no flame pulsation or dislocated flames. In addition, since the burner area can be set large or small depending on the amount of combustion, there is tolerance for changes in the fuel-air ratio caused by changes in fuel and air, and the burner area can be adjusted without causing gas odor. No deformation due to red heat occurs. By changing the ratio of the combustion parts, the combustion amount can be significantly reduced while maintaining good combustion. For example, if the ratio of the combustion parts tea and tab is 1:3, and the large combustion amount is set to 4,000 kcaf/h, even if the small combustion amount with the on-off valve 12 closed is set to 1, OOOkca4//h, The flame port load is the same value, the flame formed on the wire mesh is the same, and the TDR is 1/4, which allows the combustion amount to be varied significantly. The combustion parts 16a and 16b are provided in contact with each other, and the combustion part 1 is placed in the wake of the flame generated in the combustion part 16&.
6b, the combustion part 16b has good flame propagation and is easily ignited by the ignition from the combustion part 16a, and since the entire combustion part 16b is covered with the flame of the combustion part 16a, the combustion part 16b is easily ignited. The gas generated when 16b is turned on and off is combusted and does not flow out to the outside.

Effects of the Invention According to the present invention, a combustion section is provided in communication with each of the plurality of vaporization chambers, and the combustion sections are provided in contact with each other, and a combustion occurs in at least one combustion section.

By placing another combustion part in the wake of the flame,
Even when the combustion amount is variable, stable combustion can be maintained without changing the burner load or causing odor from unused gas, making it possible to greatly adjust the combustion amount, making it comfortable and energy-saving. Since the flame port load can be set, stable combustion can be obtained, and therefore a low NOx burner can be realized in which the flame port load is set small and the flame temperature is low.

[Brief explanation of the drawing]

The figure is a sectional view showing one embodiment of the present invention. 1... vaporizer, 3a, 3b... vaporization chamber, 7
...Blower, 9-...Fuel pump, 11...
・Aperture part, 12...Opening/closing valve, lea, 16b...
...Combustion part.

Claims (1)

[Claims] A carburetor partitioned into a plurality of vaporization chambers, a means for supplying fuel and air to each of the vaporization chambers, and a means for controlling this supply are installed, and the combustion sections are connected to each other, and the combustion sections are provided in contact with each other, A liquid fuel combustion device in which at least one combustion section has another combustion section located in the wake of a flame generated in the combustion section.