JPS6042503A - Liquid fuel combustion device - Google Patents

Abstract

PURPOSE:To prevent liquid fuel after extinguishment from dropping in an evaporating cylinder through a fuel injection nozzle, by a method wherein a heat shield pipe is installed to the inside of a blast pipe, a fuel injection nozzle is located to the interior thereof, and a flow rate of the air for combustion flowing between the blast pipe and the heat shield pipe is increased over a flow rate of the air for combustion within the heat shield pipe. CONSTITUTION:An evaporating cylinder 1 is heated by making electrical connection to a heater 2 for applying the heat, and with a blast fan 5 driven, the air for combustion is fed in the evaporating cylinder 1 through a blast pipe 4. The fuel, in turn, is injected in the evaporating cylinder 1 through a fuel injection nozzle 6 to produce air-fuel premixture which forms a combustion flame in a combustion part 7. In which case, the air for combustion fed into the evaporating cylinder 1 does not flow as much through a heat shield pipe 8, and flows mainly between the blast pipe 4 and the heat shield pipe 8. Since there is a high flow of the air for combustion in the vicinity of a connection between the blast pipe 4 and the evaporating cylinder 1, this causes increasing of a cooling effect, and permits substantial control of an increase in the temperature of the fuel injection nozzle 6 during extinguishment. As a result, a rise in temperature exercises the influence upon the liquid fuel remaining in the nozzle to expand the liquid fuel, resulting in prevention of dropping of the liquid fuel into the evaporating cylinder.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a combustion device for vaporization premix combustion using petroleum as fuel, which is applied to household heaters and the like.

Structure of a conventional example and its problems A conventional liquid fuel combustion apparatus of this type is structured as shown in FIG. That is, a heater 2 is installed in the circumferential direction of the ventral surface of the bottomed vaporizing cylinder 1, and a mixing plate 3 having a constricted shape is installed on the open surface. Furthermore, a blower pipe 4 is connected to a part of the vaporizer tube 1, and combustion air is sent into the vaporizer tube 1 through a blower fan 5, and a fuel injection nozzle 6 is passed through the blower tube 4 and into the vaporizer tube 1. I'm looking forward to it.

The fuel is vaporized and mixed with combustion air in the vaporizer cylinder 1,
It is supplied to the upper combustion section 7 and burned.

In this configuration, during steady combustion, the vaporizer cylinder 1 becomes extremely high temperature due to the influence of heat conduction from the heater 2 which is at a high temperature and the combustion section 7 which is at a high temperature due to the combustion flame. . For this reason, the temperature of the fuel injection nozzle 6, which is cooled by combustion air during steady combustion, rapidly rises due to the influence of the vaporizer cylinder 1, etc., which is at a high temperature during extinguishing.

Therefore, the liquid fuel remaining in the nozzle/I/6 at the time of extinguishing expanded due to the influence of the temperature rise, and was pushed out through the nozzle 6 and dripped into the vaporizer cylinder 1 shortly after the extinguishment. This dripped liquid fuel is vaporized in the vaporization cylinder 1, and released from the combustion section 7 as unburned gas, that is, a toxic gas containing hydrocarbon gas, carbon oxide, aldehydes, etc., and is accompanied by an extremely strong odor. There was a problem that it leaked out from the combustion equipment.

SUMMARY OF THE INVENTION The present invention solves these conventional problems and aims to prevent liquid fuel from dripping from the fuel injection nozzle into the vaporization cylinder after extinguishing the fire.

Structure of the Invention In order to achieve this object, the present invention provides a heat shield pipe inside the blast pipe joined to the vaporization cylinder, a fuel injection nozzle inside the heat shield pipe, and a space between the blast pipe and the heat shield pipe. The flow rate of combustion air flowing through the heat shield tube is made larger than the flow rate of combustion air flowing inside the heat shield tube.

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

Reference numeral 1 denotes a bottomed vaporizing cylinder, in which a heater 2 is installed in the circumferential direction of the ventral surface, and a mixing plate 3 having a diaphragm shape is installed in the open surface. Further, a blower pipe 4 is connected to a part of the vaporizer tube 1, and combustion air is sent into the vaporizer tube 1 from the blower fan 5, and a fuel injection nozzle 6 is passed through the blower tube 4 into the vaporizer tube 1. I'm so tired. The fuel is vaporized and mixed with the combustion air (arrow) in the vaporization tube 1, and the second combustion section 7
Supplied with pan-combustion. At this time, a heat shield pipe 8 is provided inside the blast pipe 4, and a fuel injection nozzle 6 is installed in the heat shield pipe 8.
is located 'C'. Also, the combustion air inlet 8a of the heat shield tube 8
% or outflow "18b" is made small so that the flow rate of combustion air inside the heat shield tube 8 is small.

With this configuration, the vaporization cylinder 1 is heated by supplying electricity to the heater 2 in the vaporization cylinder 1. Thereafter, combustion air is introduced into the vaporization cylinder 1 by driving the blower fan 5 provided with the blower pipe 4 fully valved. Subsequently, fuel is injected into the carburetor cylinder 1 from the fuel injection nozzle 6. The fuel becomes vaporized gas due to the influence of temperature on the wall surface of the vaporization cylinder 1, and -
It passes through the constriction part of the mixing plate 3 arranged at the top part and flows out to the combustion part 7. At this time, the fuel vapor gas is mixed with combustion air to form a combustion flame in the combustion section 7 as a premixture. At this time, the combustion air supplied into the vaporization cylinder 1 from the blast pipe 4 does not flow much into the heat shield tube 8, but mainly flows between the blast pipe 4 and the heat shield pipe 8.

As a result, in the vicinity of the joint between the blower pipe 4 and the vaporizing cylinder 1, the cooling effect is very strong due to the large flow of combustion air, and it is possible to significantly suppress the temperature rise of the fuel injection nozzle 6 during extinguishing. can.

In other words, due to the temperature drop caused by the combustion air near the joint between the blower pipe 4 and the vaporizer tube 1, the conduction of heat to the fuel injection nozzle 6 is reduced, and the heat conduction suppressing effect due to the heat absorption of the heat shield tube 8 is also fully exerted. can. In addition, a small 11'X flow of air very well suppresses the temperature rise of things in the atmosphere of the flow, so the temperature rise during steady combustion of fuel injection no./l/6 is negligible. There is no rest. Furthermore, when extinguishing a fire, by using a post burn for several minutes, the temperature in the vicinity of the joint between the blower pipe 4 and the vaporizing tube 1 decreases significantly after extinguishing the fire, so that the heat conduction suppressing effect of the heat shield pipe 8 becomes even greater.
No increase in temperature of the fuel injection nozzle 6 is observed.

Effects of the Invention According to the uninvented liquid fuel combustion device, a heat shielding tube is provided inside the blast pipe joined to the vaporizing tube, a fuel injection nozzle is provided inside the heat shielding tube, and a space between the blast tube and the heat shielding tube is provided. By making the flow rate of the combustion air smaller than the flow rate of the combustion air flowing inside the heat shield pipe, the fuel injection nozzle bump 1 degree after extinguishing the fire is -Iy/.

By suppressing this, the liquid fuel remaining in this nozzle expands under the influence of temperature and no longer drips into the vaporizer cylinder. As a result, as in the conventional case, after the fire is extinguished, the dropped liquid fuel is vaporized in the vaporization cylinder, and unburned gas, that is, hydrocarbon gas, is released from the combustion section.
It is possible to reliably prevent toxic scum containing carbon oxides, aldehydes, etc. from flowing out of the combustion device with an extremely strong odor, and the structure is also simple.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing a conventional liquid fuel combustion AA system, Figure 2
The figure is a sectional view showing a liquid fuel combustion device according to an embodiment of the present invention. 1... Carburizer cylinder, 4... Air pipe, 6...
...Fuel injection nozzle, 8...m Heat tube* Fig. 1q Fig. 2

Claims (1)

[Claims] A blower pipe equipped with a combustion air supply means and a fuel supply means is connected to the bottom or side surface of a bottomed vaporizing cylinder that is heated by a heater, and a heat shield pipe is provided inside the blower pipe. A fuel injection nozzle is provided as a fuel supply means on the inside of the cylinder, and the fuel injection nozzle is inserted into the vaporization cylinder. liquid fuel combustion equipment.