JPS6131764B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid fuel combustion device in which air is applied to a vaporization element impregnated with liquid fuel, and an amount of liquid fuel corresponding to the amount of air is vaporized and burned from the vaporization element. The purpose is to achieve good combustion with less generation of yellow flame, soot, etc.

An example of this will be explained below with reference to the drawings.
Reference numeral 1 denotes a long linear fuel supply unit built into the lower part of the heat exchange case 2, which is made of aluminum die-casting with good thermal conductivity, and whose upper peripheral edge 3 is fitted into the wall of the heat exchange case. It is fixed in an airtight state.

An oil chamber 4 with an open upper surface is integrally formed approximately in the center of the fuel supply body 1, and an oil reservoir chamber 6 communicating through a slit hole 5 is integrally formed on the side of the oil chamber. be. As shown in FIG. 3, this oil reservoir chamber 6 is divided into three chambers 8, 9, and 10 by a partition wall, and the fuel flows from the fuel pipe 11 connected through the heat exchanger wall as indicated by the arrows a, b. The excess fuel flows into the oil chamber 4 as shown in FIG. 3C, and at the same time, the excess fuel overcomes the weir 13 that keeps the oil level constant and flows out into the return pipe 14 to the fuel tank (not shown). Reference numeral 15 denotes a vaporizing wick inserted into the oil chamber 4 of the fuel supply body 1, which sucks up liquid fuel accumulated in the oil chamber 4 by capillary action and contains it in a liquid phase. There is. This vaporizing core 15 is made of petalite (alumina approx.
A mixture of 50% by weight, 100% by weight of silica, 10% by weight of Cobalon, 10% by weight of starch, 3% by weight of barium oxide, and 12% by weight of polyvinyl alcohol is molded and baked at approximately 1250℃. After firing, it consists of 100% by weight of petalite (about 50% by weight of alumina, about 50% by weight of silica) and 3% by weight of barium oxide, and the other components are fired to create the vent.

Further, this vaporizing wick 15 has a U-shaped notch 15a formed at the top face facing an ignition heater, which will be described later. Reference numeral 16 denotes a holder for holding the vaporizing wick 15, which covers the lower outer surface of the vaporizing wick 15 as shown in FIG.
7 is suspended by being engaged with recesses 18 provided on both side opening edges of the oil chamber 4. As a result, a fuel passage gap t is formed between the bottom of the vaporizing wick and the bottom of the oil chamber, and the fuel from the slit hole 5 spreads over the entire area of the vaporizing wick 15 through this gap t. Note that this fuel is drawn up into the vaporizing wick 15 through an opening 19 provided on the lower surface of the holder 16.

20 is a burner housing that forms a mixing chamber/combustion chamber 21 surrounding the upper part of the vaporizing wick 15 and a main combustion chamber 22, and is located on both sides of an outer chamber plate 22 which is bent into a substantially U-shaped cross section as shown in FIG. A side wall plate 23 is fixed to the surface, and an inner wall plate 24 is fixed to the inside and upper surface of the side wall plate 23 to form a hollow box shape. The burner housing 20 has primary air holes 2 in both combustion chamber walls communicating with a hollow part 26.
7, 27a, and a large number of secondary air holes 28 are formed, and air is supplied from these air holes 27, 27a, 28 to vaporize the fuel in the vaporization wick 19 facing into the mixing chamber/combustion chamber 21. It is designed to let it burn. Among these air holes, primary air holes 27, 2
7a, especially the first stage air hole 27,
The flame formed from this collides with the side surface of the vaporizing wick 15, and the flame spreads from side to side to form a belt-like pitch, for example, about 6 mm. The air holes 27a in the second stage are formed at appropriate intervals, for example, at a ratio of one to two air holes 27 in the first stage, for the purpose of stabilizing the flame from the first stage. 27a are formed on the same line. Furthermore, among the two air holes 27, 27a, the left and right air holes in the first stage are opposed to each other, and those in the second stage are shifted in position in a staggered arrangement. Further, at least one of the left and right air holes 27 of the first stage is set to be located opposite to the notch 15a provided in the vaporizing wick 15.
On the other hand, the burner casing 20 has an opening 30 facing the mixing chamber/combustion chamber 21 on the bottom surface of its outer wall plate, and the upper surface of the fuel supply section body 1 is arranged such that the opening 30 faces and matches the oil chamber 4 of the fuel supply section body 1. It is mounted and fixed on.
Four air holes 33 are formed in the bottom surface of the hollow portion 26 of the burner housing 20.
3 matches the four air holes 34 provided on the upper surface of the fuel supply unit body 1, and air is obtained from an air supply pipe 35 with an air amount variable damper 35a connected to the lower part of the heat exchanger. ing.

Reference numeral 37 designates a heater guide that extends through the side of one of the hollow portions 26 of the burner housing 20, into which an ignition heater 38 that projects above the notch 15a of the vaporizing wick 15 is fitted so as to be freely insertable and removable. Reference numeral 40 denotes a flame stabilizing plate attached to the left and right walls in the longitudinal direction of the mixing chamber/combustion chamber 21 so as to face each other. It is bent downward at an inclination angle of about 40 degrees from a position slightly above 27a and is inclined 40b. This downwardly bent piece 40b has a notch 41a in a portion facing the second stage primary air hole 27a, and a protruding portion 41 is provided in the portion facing the first stage primary air hole 27.
It is listed as b. Further, an opening 42a for escape of the heater is formed in the flame holding plate 40 on the side from which the ignition heater 38 projects, and an opening 42b facing this opening 42a is formed in the other flame holding plate 40. Note that consideration is given so that no primary air hole 27 exists in the combustion chamber wall facing this opening 42b.

Reference numeral 44 denotes a flame regulating plate fixed to the upper surface of the burner housing 20, and an opening 45 facing the upper opening edge of the main combustion chamber 22 is formed approximately in the center. This opening 45 is formed smaller than the upper opening of the main combustion chamber 22, and is set such that its opening edge protrudes inward over the entire circumference.

In the above configuration, the liquid fuel supplied to the oil reservoir chamber 6 enters the oil chamber 4 through the slit hole 5 and is sucked up into the vaporizing wick 15 by capillary action. The air supplied from the air supply pipe 35 is supplied to the air hole 3.
The primary and secondary air holes 27, which enter the hollow part 26 of the burner housing 20 through the combustion chamber walls 3 and 34
Each combustion chamber 21, according to the cross-sectional area ratio of 27a, 28
22. At this time, the air from the primary air hole 27 hits the surface of the vaporizing wick 15.
evaporates the fuel contained in it and mixes it with it.
Therefore, when the ignition heater 38 is energized to make the element 38' red-hot, the heat ignites and starts combustion. The amount of vaporization increases due to this heat of combustion, and a part of it is burned by the primary air from the primary air holes 27 and 27a, or most of it rises as it is and is supplied from the secondary air hole 28. secondary air is obtained, resulting in green combustion.

Here, the size of the above combustion flame is the primary air hole 2.
It is determined by the amount of air supplied from 7 and 27a. In other words, the air supplied near the vaporizing wick mixes with the vaporized fuel from the vaporizing wick 15 to create a mixed gas in the flammable range, but the larger the amount of air supplied, the smaller the amount of mixed gas in the flammable range. It will become less. Therefore, the size of the combustion flame is proportional to the amount of air supplied. The amount of vaporized fuel vaporized from the vaporization wick 15 is proportional to the size of the combustion flame (the amount of heat). Therefore, in this combustion device, if the amount of air to be supplied is changed, the amount of combustion will change accordingly. The amount of air and the amount of fuel always maintain a substantially constant relationship (the air-fuel ratio is substantially constant), resulting in good combustion.

In addition, in this combustion device, since the number of primary air holes 27 and 27a in the first and second stages is increased, the amount of vaporized fuel from the vaporizing wick 15 is inevitably increased, and the atmospheric temperature in the primary flame formation area is high. becomes. In addition, the temperature of the second-stage primary air holes 27a becomes particularly high because the flames formed in the air holes 27a come into contact with each other. For this reason, the vaporized fuel rising from the first-stage primary air hole 27 without being completely burned is thermally decomposed between the primary air holes 27a, which tends to generate yellow flame, soot, and the like. In other words, when the amount of combustion is increased, yellow flame, soot, etc. are more likely to be generated. However, in this combustion apparatus, the protruding part 41b of the flame stabilizing plate 40, which is in a relatively low temperature state due to contact with the air from the second stage primary air hole 27a, is located in the high temperature part and lowers the temperature of this part. Become. Therefore, even though the combustion amount is high, good combustion can be expected with less generation of yellow flame, soot, etc. In addition, the protruding portion 41b of the flame stabilizing plate 40 diffuses the mixed gas of vaporized fuel and air rising from the vaporizing wick 15, which has the advantage of improving the combustion state. In addition, the combustion width is widened due to the diffusion effect of the protrusion 41b, and the combustion state during extinguishing becomes stable and good. Also, the edge of the notch 40b of this flame stabilizing plate 40 is connected to the primary air hole 2 of the second stage.
7a, the flame formed in the primary air hole 27a protrudes inwardly and upwardly from the edge, and during extinguishing, the combustion flame sinks and the vaporizing wick 15 becomes red hot. If you restart the operation while dry firing is in progress, the primary air hole 27
There is also the advantage that the flame formed in a is smoothly transferred to the secondary air hole 28 portion, and there is no explosion phenomenon caused by delayed flame transfer, thereby improving safety.

As described above, according to the present invention, not only the combustion is stabilized due to the presence of the flame-holding plate, but also the generation of soot, yellow flame, etc. can be reduced by the protrusion provided on the flame-holding plate. Even if it is a high combustion type, the combustion state will be very good, and the effect is great.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a liquid fuel combustion device according to an embodiment of the present invention, FIG. 2 is a side view with a side thereof partially cut away, and FIG. 3 is a plan view with the same portion cut away. , Figure 4 is a perspective view, Figure 5 is A of Figure 2.
-A' line sectional view, Figure 6 is a plan view taken along B-B' line in Figure 2, Figure 7a is a C-O-
A cross-sectional plan view taken along the O'-C' line, Figure 7b is D in Figure 6.
It is a cross-sectional plan view taken along the line -O-O'-D'. 15... Vaporization wick, 27, 27a... Primary air hole, 38... Ignition heater.

Claims (1)

[Claims] 1. A heat-resistant porous vaporization wick containing liquid fuel in a liquid phase, a plurality of rows of air holes that supply air near the vaporization wick, and a vaporization wick arranged near the vaporization wick to prevent vaporization from the vaporization wick. It is equipped with an ignition heater that ignites the fuel and a flame-holding plate that holds the flame formed by the ignition of the ignition heater, and among the plurality of air holes, the air holes in the air hole row closest to the flame-holding plate are the other air holes. The number of air holes is smaller than the number of air holes in the air hole row, and the flame stabilizing plate is provided with protrusions located correspondingly between the air holes in the air hole row.