JPH05340511A - Combustion apparatus of warm air heater - Google Patents

Abstract

(57) [Summary] [Purpose] For example, regarding a hot-air heater such as an oil fan heater, the purpose is to ensure the stability of combustion even if the difference in calorific value between strong combustion and weak combustion is large. [Structure] A partition plate 14 is provided at an outer peripheral position of a burner flame hole 16 in a combustion section, and a combustion enclosure 5 is provided in a combustion chamber 3 and a burner box 4.
The secondary air introduction part 34 and the baffle plate 18 for guiding the secondary air introduced from the secondary air introduction part 34 to the combustion chamber 3 on the rear surface of the combustion chamber 3 below the center of the combustion chamber 3 are in contact with the combustion flame 21. The discharge portion 20 of the secondary air from the baffle plate 18 in the combustion chamber 3 provided in the combustion chamber 3 is located above the secondary flame height at the time of minimum combustion, and the discharge portion 20 is not provided. , The discharge part 2 is located below the secondary flame height at the time of maximum combustion.
Secondary air from 0 is provided at a position substantially orthogonal to the combustion flame 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion device used in a petroleum vaporization type hot air heater such as an oil fan heater, and more specifically, it has a large difference in calorific value between strong combustion and weak combustion. The present invention relates to a combustion device capable of ensuring combustion stability.

[0002]

2. Description of the Related Art Conventional combustion equipment (hereinafter referred to as conventional equipment)
Will be described with reference to FIGS. 7, 8, 9, and 10. FIG. 7 is a partially cutaway front sectional view of the conventional apparatus, FIG. 8 is a front sectional view of a main portion of a burner portion of the conventional apparatus, and FIGS. 9 and 10 are side sectional views schematically showing the conventional apparatus. First, the structure of the combustion section of the conventional device will be described with reference to FIGS. The vaporized fuel 11 obtained by previously heating and vaporizing the liquid fuel is injected from the nozzle 8 of the vaporizer 7 into the burner 13, and the required amount of the primary air 10 for combustion is also naturally sucked into the burner due to the ejector effect of this fuel gas injection. And after being mixed inside it
It burns in the burner flame hole portion 16. Burner 13 is combustion chamber 3
And a combustion enclosure 5 formed by the burner box 4.

The secondary air for combustion is supplied from the lower hole 41 of the burner box 4, and the combustion exhaust gas above the burner 13 is discharged to the outside of the combustion chamber 3 by the draft effect by the air blow of the convection blower 9 attached to the main body of the equipment. After being mixed with the indoor air taken in by the convection blower 9, the air is discharged from the louver 6 into the room. As shown in FIG. 10, the secondary air for combustion may be supplied not only from the lower hole 41 of the burner box 4 but also from an opening 32 opened to the combustion chamber 3.

[0004]

In recent years, warm air heaters have tended to reduce the amount of weak heat generation in order to obtain a large difference in the amount of heat generation during strong combustion and during weak combustion, particularly in order to pursue comfort. In such a case, it is important to control the pressure difference between the inside and the upper portion of the burner 13 and the flow velocity at the burner flame hole 16 in order to secure the stability of combustion in the weak combustion. In the structures of FIGS. 9 and 10, these factors are affected by the amount of air blown by the convection blower 9, the amount of primary air for combustion 10, the amount of secondary air, etc., but both strong combustion and weak combustion produce combustion exhaust gas. characteristics (i.e. CO / C0 ₂ regulation value), combustion in addition to satisfy the stability, in particular hot air temperature during weak combustion, the temperature rise of each part, problems there are adjustment of the amount of each of such backfire, etc. Is really tough.

Further, the odor of combustion exhaust gas becomes a problem as the amount of weak heat generation is reduced. This is due to instability of combustion and combustion vaporized gas drifting inside the equipment flowing into the combustion chamber 3. In FIGS. 9 and 10, the secondary air for combustion is the air inside the equipment at the bottom of the burner box. The cold secondary air 42 is taken in from the hole 41 and cools the burner 13, and a small amount of fuel vaporized gas from the burner box lower hole 41 (evaporation from the refueling tank 12, the auxiliary tank 15 and the like in FIG. 7). Since the fuel mist) also comes into contact with the combustion flame, it is not preferable in terms of odor.

Therefore, in FIG. 10, the secondary air for combustion is taken in exclusively from the combustion chamber opening 32 when the lower burner box hole 41 is closed. The required amount of primary air and secondary air for combustion varies greatly depending on the amount of heat generated. In the case of the Bunsen system, the primary air amount is adjusted by naturally sucking the required amount according to the heat generation amount by the ejector effect of the combustion gas injection, and in the case of the combustion pressure system, controlling the rotation speed of the combustion blower.

As described above, it is very difficult to balance the amount of secondary air according to each heat value. A blower dedicated to the secondary air may be used, or the opening / closing degree of the secondary air holes may be mechanically adjusted, but the mechanism is complicated and it is not suitable as a household heater due to cost and the like. If the primary air is sufficient, the amount of secondary air may be unnecessary or may be small, but in this case,
When primary air becomes insufficient due to oxygen deficiency and the like, and combustion of red fire occurs, the generation of carbon monoxide (CO) significantly increases. Also, if the secondary air is added too much, the flame during weak combustion will be cooled too much and combustion failure will occur, causing odor and depending on the extent carbon monoxide (CO)
The occurrence of is also increased.

For example, the required secondary air amount at the time of strong combustion differs greatly from that at the time of strong combustion such that it is good at the time of weak combustion but bad at the time of strong combustion. Carbon oxide (CO) generation increases. In particular, a large amount of dust adheres to the fan guard of the convection blower,
Assuming that the wind suction performance has deteriorated, two sheets of gauze are laminated and attached to the fan guard of the convection blower, and if the amount of air blown by the convection blower is artificially reduced, carbon monoxide generation increases. "Incomplete combustion prevention device test" according to JIS standard, so-called oxygen deficiency digestion test (hereinafter referred to as oxygen deficiency digestion test), that is, when combusted in a closed room, oxygen deficiency due to the combustion is sensed, and a safety device is used as a combustion device. Table 2 shows the measurement data when digested. The JIS standard requires CO / CO _{2 to} be 5/1000 or less.

[0009]

[Table 2]

In Table 2, for both specifications A and B, the burner box lower hole 41 is completely shielded, and the secondary air is taken in only through the combustion chamber opening 32. Specification A: 5-φ8 hole on the back of the combustion chamber (100m height of hole center position from the bottom of the combustion chamber)
m) 5-φ8 hole (Hole center position height from bottom of combustion chamber 70m
m) Furthermore, there is a 5-φ5.2 hole on the front of the combustion chamber (hole center height 12m from the bottom of the combustion chamber.
m) Specification B: 5-φ8 hole on the back of the combustion chamber (100m height of hole center position from the bottom of the combustion chamber)
m) Strong combustion ・ ・ ・ 3000kcal / h Strong combustion A ・ ・ ・ ・ 3000kcal / h (two gauze layers are attached to the fan guard of the convection fan to reduce the secondary air intentionally) Weak Combustion: 500 kcal / h According to Table 2, CO / C0 ₂ is large at strong combustion A according to JIS
Does not meet the standard. Therefore, the present invention has been made in view of the above circumstances, and even if the difference in the calorific value between the strong combustion and the weak combustion is large, the stability of the combustion is ensured and the warm air heater having the structure capable of generating and supplying the combustion odor is provided. Is to provide.

[0011]

In order to achieve the above-mentioned object, the present invention provides a combustion plate containing a combustion device and surrounding a combustion flame with a partition plate at an outer peripheral position of the burner flame hole, and an outer periphery of the burner flame hole. That is, the combustion enclosure is divided at the position. Further, an air guide plate that takes in the air from the convection blower as the secondary air for combustion is provided in the combustion chamber. Furthermore, the secondary air introduction part of the baffle plate is located above the burner burner hole position of the combustion part and below the center of the combustion chamber, and its discharge part is higher than the height of the secondary flame at the time of minimum combustion. It is located above and below the secondary flame height at the time of maximum combustion when there is no wind emission part. Further, the opening serving as the secondary air discharge portion of the baffle plate is provided at a position where the wind is discharged in a direction substantially orthogonal to the combustion flame. The baffle plate is in contact with the combustion flame in the combustion chamber.

[0012]

By partitioning the combustion chamber by the burner flame hole portion, the pressure difference between the inside and the upper portion of the burner and the burner flame hole portion flow velocity can be made higher than before, and the combustion state can be stabilized. Further, even if there is a slight vaporization gas leak from the burner or fuel vapor drifting in the equipment, it is possible to prevent these from flowing into the combustion chamber, which leads to reduction of combustion odor. Further, since a wind guide plate is provided on the back surface of the combustion chamber to introduce the air from the convection blower as secondary air, a sufficient amount of secondary air can be secured even in the case of strong combustion. In the case of weak combustion, the secondary flame is low and is below the position of the secondary air discharge portion of the baffle plate, so that the secondary air discharge is not affected. Weak combustion is 500
In the case of kcal / h, secondary air is almost unnecessary. Therefore, the secondary air can be taken in with good balance in both strong and weak combustion. In addition, secondary air is vigorously ejected from the openings of the baffle plate, is mixed perpendicularly with the combustion flame at the time of strong combustion, and the secondary air is sufficiently supplied. Then, since the combustion flame in the combustion chamber is in contact with the baffle plate, the baffle plate is heated by the flame and the secondary air introduced from the convection blower is heated and then supplied as secondary air. Cooling is suppressed, combustion stability is improved, and generation of carbon monoxide CO and nitrogen dioxide NO ₂ is also suppressed.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A detailed description will be given below of embodiments embodying the present invention with reference to the accompanying drawings. It should be noted that the following examples are specific examples and do not limit the technical scope of the present invention. The same components as those in the conventional technique are designated by the same reference numerals. 1 is a side sectional view showing a schematic structure of an oil fan heater according to a first embodiment of the present invention, and FIG. 2 is a view taken along the line H-H 'in FIG. Liquid fuel is preheated and vaporized fuel 11 and primary air for combustion 1
0 is sent into the burner 13, mixed inside, and burned in the burner flame hole portion 16 (see FIGS. 7 and 8). The combustion enclosure 5 is formed by the combustion chamber 3 and the burner box 4, and is divided vertically by the partition plate 14 at the burner flame hole position.

As the secondary air 17 for combustion, the wind from the convection blower 9 is introduced from the opening 34 on the back surface of the combustion chamber 3, and the baffle plate 18 is provided.
Is introduced into the combustion flame. The combustion exhaust gas is discharged to the outside of the combustion chamber 3 through the opening 31 in the upper part of the combustion chamber 3 due to the draft effect of the air blow of the convection blower 9 attached to the device body, and mixed with the indoor air taken in by the convection blower 9. The warm air is discharged from the rear louver 6 into the room.
As a result of partitioning by the partition plate 14 at the burner flame hole position, the secondary air does not flow around the burner flame hole portion, so that turbulence of the flame is suppressed and combustion stability is increased. Further, the flow velocity of the mixed gas of the vaporized fuel and the primary air in the burner flame hole portion increases, and the combustion speed increases. The result of measuring the ion current of the combustion flame as an index of combustion stability is shown in FIG.

In FIG. 6, the measured values a and b at the time of weak combustion in the structure of the embodiment of the present invention shown in FIG. 1 and the structure of the conventional example shown in FIG. 9 are compared. It can be seen that in (a), the fluctuation of the ion current is small and the combustion is stable. Also, when the odor of warm air blown out from the louver portion is compared in the sensory test of the monitor, the result of the structure a of the present invention is better than that of the conventional structure b. It is considered that this is because the delicate flow of the kerosene vaporized gas floating in the equipment was suppressed and the stable combustion led to the reduction of odor. Combustion chamber 3 for secondary air 17
The secondary air introduction part 34 on the back surface of the combustion chamber has a height of 10 to 50 mm, though it is introduced only to the back surface of the combustion chamber.
The width is about 50 to 150 mm, which is several steps larger than the conventional secondary air intake hole, and the secondary air can be sufficiently taken in. However, the size of the secondary air introducing portion 34 is the amount of heat generation,
It depends on conditions such as the size of the burner 13, and the above is an example.

Further, the secondary air introducing portion 34 is located in the lower part of the combustion chamber 3, and since this position corresponds to the peripheral portion of the propeller fan of the convection blower 9, a sufficient air volume can be secured. The taken-in secondary air 17 rises along the baffle plate 18 and is discharged into the combustion chamber 3 from the secondary air discharge portion 19 which is an upper opening, and is mixed with the combustion flame. Here, the combustion flame 22 (indicated by a broken line in FIG. 1) at the time of weak combustion is lower than the opening 19 of the baffle plate 18 and is not affected by the combustion flame 22 so that the flame is not burned and stable combustion is achieved. Is obtained.

Further, as is clear from FIG. 1, the baffle plate 18
Has a taper shape, and comes into contact with the combustion flame and is heated. When passing through the heated air guide plate 18, the secondary air 17 is heated, the rapid cooling of the combustion flame by the secondary air is suppressed, the stability of combustion is improved, and carbon monoxide CO, nitrogen dioxide NO ₂
The occurrence of is also suppressed.

FIG. 3 is a side sectional view showing a schematic structure of an oil fan heater according to a second embodiment of the present invention. The secondary air discharge portion of the baffle plate 18 of the first embodiment shown in FIG. The opening 19 is closed and an opening 20 is provided on the side surface of the baffle plate 18. 4 and 5 are views taken along the line KK 'in FIG. 3, showing an embodiment of the secondary air discharge portion opening 20 on the side surface of the baffle plate.

In the case of the second embodiment, as in the case of the first embodiment, the secondary air 17 is taken in through the secondary air inlet 34 on the back surface of the combustion chamber 3 and rises along the baffle plate 18. Then, it is discharged into the combustion chamber 3 through the opening 20 located in the upper part of the front surface of the baffle plate and mixed with the combustion flame. Here, the positional relationship between the secondary air inlet and the combustion flame at the time of strong combustion and weak combustion of the discharge opening is the same as in the case of the first embodiment described above.

In this second embodiment, the secondary air is the air guide plate 1.
8 is vigorously ejected from the discharge openings 20 and mixed with the combustion flame 21 at the time of strong combustion at right angles. At this time, something like a secondary air wall 23 is formed on the upper part of the combustion flame,
Secondary combustion will occur at this position. Therefore, even if the primary air becomes insufficient, such as when the combustion air is deficient in oxygen, resulting in red-fire combustion, and conventionally, even when the generation of carbon monoxide CO increases, the secondary air is sufficiently supplied and the secondary combustion is performed. The generation of carbon monoxide CO is suppressed. The above-mentioned “wall of secondary air 2
Due to the presence of 3 ″, the red fire oxidizes and burns here to become a normal, almost transparent secondary flame. Furthermore, since the secondary air is sufficiently supplied, it has the effect of lowering the temperature of the combustion flame, and the nitrogen oxide N
O _X of the product is reduced. In the case of weak combustion, the position of the secondary air discharge opening 20 is above the position of the combustion flame 22 as in the first embodiment, and there is almost no effect of the secondary air.

In the case of the embodiment of FIG. 5, unlike the case of FIG. 4, the secondary air discharge opening 20 of the baffle plate 18 has a slit shape, but even in this case, the same effect as in FIG. 4 can be obtained. ..
Table 1 shows the measurement data of the oxygen deficiency digestion test based on the first and second examples of the present invention.

[0022]

[Table 1]

Here, in both the first and second embodiments, there is a partition plate 14 in the burner box and the combustion chamber, and the secondary air is taken in through the baffle plate 18 from the opening 34 on the rear surface of the combustion chamber. ☆ Strong combustion ・ ・ ・ 3000kcal / h ☆ Strong combustion A ・ ・ ・ 3000kcal / h (This is the one that intentionally reduces the secondary air by sticking two pieces of gauze on the fan guard of the convection blower. (Assuming a case where a large amount of dust adheres to the fan guard and wind suction performance deteriorates.) ☆ Weak combustion ・ ・ ・ 500 kcal / h According to Table 1, CO / CO ₂ is JIS standard 5/1000.
In addition to satisfying the following requirements, the measurement data of the conventional device is greatly improved from Table 2. (Strong combustion A)

[0024]

As described above, the present invention is good even if the partition plate is provided at the outer peripheral position of the burner flame hole in the combustion chamber to further stabilize the combustion state and to reduce the calorific value during weak combustion more than ever before. Combustion can be reduced and odor can be reduced during combustion, which can further improve comfort as a heater. In addition, by installing a baffle plate in the combustion chamber to take in the secondary air from the convection blower, there is almost no effect in the case of weak combustion, and a sufficient amount of secondary air is taken in in the case of strong combustion. You can This generation of carbon monoxide CO suppressed from, yet there is provided a high kerosene fan heater valuable that achieves also stable effect of suppressing the generation of nitrogen oxides NO _X with the combustion can be obtained.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a schematic structure of an oil fan heater according to a first embodiment of the present invention.

FIG. 2 is a view taken along the line H-H 'in FIG.

FIG. 3 is a side sectional view showing a schematic structure of an oil fan heater according to a second embodiment of the present invention.

FIG. 4 is a view taken along the line KK ′ of FIG.

5 is a K of FIG. 3 showing a secondary air discharge opening different from that of FIG. 4;
-K 'arrow view.

FIG. 6 shows fluctuation measurement data of ion current during weak combustion according to the present invention.

FIG. 7 is a partially cutaway front sectional view of a conventional oil fan heater.

FIG. 8 is a front sectional view of a main portion of a burner portion of a conventional device.

FIG. 9 is a side sectional view showing a schematic structure of a conventional device.

FIG. 10 is a side sectional view showing a schematic structure of another conventional device.

[Explanation of symbols]

 3 Combustion Chamber 4 Burner Box 5 Combustion Enclosure 6 Louver 7 Vaporizer 8 Nozzle 9 Convection Blower 10 Combustion Primary Air 11 Vaporized Fuel 12 Refueling Tank 13 Burner 14 Partition Plate 15 Auxiliary Tank 16 Burner Flame Hole 17 Combustion Secondary Air 18 Baffle plate 19 Secondary air discharge part 20 Secondary air discharge part (opening on side surface of baffle plate) 21 Combustion flame at the time of strong combustion 22 Combustion flame at the time of weak combustion 23 Wall of secondary air 34 Secondary air introduction Department

Claims (5)

[Claims] 1. A warm air heater having a combustion enclosure including a combustion chamber enclosing a combustion flame from a burner flame hole and a burner box enclosing the burner, wherein the combustion enclosure is located at an outer peripheral position of the burner flame hole. A partitioning plate for partitioning the combustion chamber from the burner box is provided in the combustion device of the warm air heater. 2. A warm air heater having a combustion enclosure including a combustion chamber enclosing a combustion flame from a burner burner hole and a burner box enclosing the burner, wherein convection is performed as secondary air for combustion in the combustion chamber. A combustion device for a warm air heater, which is provided with a baffle plate that takes in air from a blower. 3. The secondary air introduction part of the baffle plate is located above the burner burner hole position in the combustion part and below the center of the combustion chamber, and the secondary air discharge part is the secondary air discharge part during minimum combustion. The combustion of the warm air heater according to claim 2, wherein the combustion is located above the height of the flame and below the height of the secondary flame at the time of maximum combustion when there is no secondary air discharge portion. apparatus. 4. The warm air heating according to claim 2, wherein the opening serving as the secondary air discharge portion of the baffle plate is located at a position where the air is discharged in a direction substantially orthogonal to the combustion flame. Machine combustion equipment. 5. The combustion device for a warm air heater according to claim 2, wherein the baffle plate contacts the combustion flame.