JPS6113131B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for sucking up liquid fuel through a vaporizing wick,
This liquid fuel combustion device vaporizes and burns this fuel, and is designed to prevent abnormal combustion even if it is re-ignited immediately after extinguishing the fire.

First, an example of a liquid fuel combustion device that sucks up liquid fuel through a vaporization wick, vaporizes the fuel, and burns it will be explained with reference to FIG. 1. 1 is the lower body of the combustion device, which has a hollow shape. An oil chamber 2 is recessed in the center of the upper surface. 3 is a ventilation passage that supplies air to the hollow part 3 of the lower body 1;
Air conditioning means 4 such as a damper is provided. Reference numeral 5 denotes a fuel passage that supplies liquid fuel to the oil chamber 2 of the lower front main body 1, and a constant liquid level A is always maintained by a constant liquid level device or by returning excess fuel to a tank (not shown). The fuel supply is controlled by a fuel control means 6 such as a pump or an on-off valve provided in the middle of the fuel passage 5.
Reference numeral 7 denotes a vaporizing wick that is removably fitted into the oil chamber 2 of the lower body 1, and is made of a heat-resistant porous material such as porous ceramic, and is connected to the oil chamber wall by a holder (not shown) or the like. They are maintained so that a gap t is formed between them through which the liquid fuel circulates. Reference numeral 8 denotes an upper body covered over the lower body 1 so as to surround the upper part of the vaporizing wick 7, and an air chamber to which air is supplied through vent holes 9 and 10 is provided on the outer periphery of the combustion chamber wall surrounding the upper part of the vaporizing wick. 11 is formed. A primary air hole 12 is formed in the combustion chamber wall of the upper body 8 in a portion facing the vaporizing core, and a secondary air hole 13 is formed above the primary air hole 12. 14 is a flame holding plate, and 15 is an ignition heater.

In the above configuration, in this combustion device, first, the vaporizing wick 7 sucks up the liquid fuel in the oil chamber 2, and then air supplied from the primary air hole 12 is obtained, a part of which is vaporized, and the ignition heater 15 The vaporized fuel is mixed with the air from the primary air hole 12 to form a mixed gas in the combustible range, which obtains the heat of the ignition heater 15 and ignites. Then, the vaporized fuel that could not be completely combusted with only the primary air from the primary air hole 12 obtains secondary air from the secondary air hole 13 and is completely combusted. In addition, in the combustion device shown here, the primary air hole 12
By changing the amount of primary air supplied from the vaporizer wick, the gas phase pressure near the vaporizer core changes, and the pressure balance with the liquid phase pressure of the liquid fuel in the vaporizer wick is disrupted, resulting in an increase in the amount of vaporized fuel, that is, the amount of fuel available for combustion. The amount of fuel consumed changes, causing the amount of combustion to fluctuate. That is, simply changing the amount of air changes the amount of combustion, which has the advantage of keeping the mixture ratio of air and fuel (air-fuel ratio) constant at all times, resulting in stable combustion.

By the way, in a combustion device using such a vaporizing wick 7, the liquid fuel turns into tar and clogs the hole of the vaporizing wick 7, similar to the wick of an oil stove.
If used for a long period of time, there is a risk that the initial characteristics may no longer be obtained. Therefore, in such a combustion device, when extinguishing a fire, only the liquid fuel is stopped and combustion air is continued to be supplied to completely burn out the fuel contained in the vaporizing wick 7, and also to burn out the tarred material. It is necessary to perform grilling. In this case, the temperature of the vaporizing wick 7 after extinguishing becomes extremely high.
When liquid fuel is supplied for re-ignition, the vaporizing wick 7
All of the liquid fuel sucked up vaporizes at once, resulting in excess fuel and abnormal combustion such as standing flames and explosive combustion. This is because if the heat capacity of the vaporizing wick 7 is made extremely small, it will be cooled down to a low temperature immediately after the fire is extinguished, so temporary vaporization will not occur, and the above-mentioned problems such as standing flames can be solved, but in practice It's impossible.

Therefore, in the present invention, the vaporizing wick 7 is actively cooled, and as shown in an example of the control circuit in FIG. Although not shown in the figure, the ventilation passage (provided in a part of the ventilation passage 3) is driven. That is, in FIG. 2, 16 is an operation switch, and 17 is a blower fan, which is directly connected to the operation switch 16 together with fuel control means 6 such as a pump. The ignition heater 15 is connected to the operation switch 1 via a delay switch 18 that is turned on after a certain period of time has passed after the operation switch 16 is turned on.
It is connected to 6. Therefore, the operation switch 16
When turned on, the blower fan 17 rotates before the ignition heater 15 generates heat, and the vaporizing wick 7 is cooled by air from the primary air hole 12. In this embodiment, as the blowing fan 17 rotates, the fuel control means 6 is also energized and opened, and liquid fuel is supplied to the vaporizing wick 7. Therefore, the vaporizing wick 7 is cooled by this liquid fuel as well as the air mentioned above, and since this liquid fuel permeates into the inside of the vaporizing wick 7, the cooling effect is large and it only takes a very short time. The temperature will drop in time. When the temperature reaches this low temperature, the delay switch 18 is turned on and the ignition heater 15 generates heat.
Ignition combustion will begin as described above. Therefore, all of the liquid fuel will not temporarily vaporize and burn during this ignition.

Note that 19 in Fig. 2 indicates the ignition heater 1 after the ignition operation.
Auxiliary delay switch 2, which closes a little later than delay switch 18, is a relay for cutting off power to 5.
The delay switch 20 is connected to the operation switch 16 via the ignition heater circuit 20, and is activated when the delay switch 20 is turned on to open the relay switch 21 of the ignition heater circuit. Further, 22 is a thermoswitch that is turned ON by directly or indirectly sensing the combustion heat of the vaporizing wick 7, and is ON until the liquid fuel contained in the vaporizing wick 7 is completely burned after the operation switch 16 is turned off. Then, the blower fan 17 continues to rotate, making dry firing possible. In other words, it is a dry-fire switch. In this case, if the fuel control means 6 remains open, dry firing will not be possible, so the fuel control means 6 is turned on together with the operation switch 16.
It is connected to turn off.

As explained above, according to the present invention, good combustion can be maintained over a long period of time by dry-firing the vaporizing wick, and safe re-ignition without explosion etc. is also possible after this dry-burning. . In addition, the vaporizing wick after dry firing is cooled not only by air from the blower but also by fuel from the fuel control means, so the vaporizing wick is rapidly cooled and the waiting time for relighting is short and convenient. The effect is great, such as becoming a valuable person.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the structure of a liquid fuel combustion device according to an embodiment of the present invention, and FIG. 2 is an electric circuit diagram thereof. 6... Fuel control means, 7... Vaporizing wick, 15...
Ignition source, 16... Operation switch, 17... Air blowing means (air fan), 18... Delay switch, 22
...Air-baked switch.

Claims (1)

[Claims] 1. A heat-resistant porous vaporizing wick that sucks up and vaporizes liquid fuel, a fuel control means that controls fuel supply to the vaporizing wick, a blowing means that supplies air near the vaporizing wick, and the vaporizing wick. and an ignition source for igniting the vaporized fuel from the air blower, the blowing means is connected in series to an operation switch and a dry firing switch connected in parallel thereto, and the ignition source is connected to the operation switch via a delay switch, and The fuel control means for controlling the fuel supply to the vaporizing wick is a liquid fuel combustion device connected to be turned on and off together with an operation switch.