JPH0875118A - Liquid fuel combustion apparatus - Google Patents

Abstract

PURPOSE: To prevent back fire from being produced while uniformizing a flame by providing many small holes in a top surface part and an annular flat plane part of a topped cylinder part in a protruded mixing and rectifying cylinder having the topped cylinder part at the center and the annular flat plane part on the lower outer periphery. CONSTITUTION: Mixed gas from a vaporization cylinder 10 flows into a protruded mixing and rectifying cylinder 33 disposed in a burner head 29 through a drawing passage 25A of a drawing part 25. Part of the mixed gas flowing into the mixing and rectifying cylinder 33 flows to a lower stage flame hole 30 through many small holes 36, 37 provided in an annular flat plane part 35 and is jetted from each lower flame hole 30 for combustion, and remaining mixed gas rises in the topped cylinder part 34 and flows to the upper stage flame hole 30 through many small holes 36, 37 provided in a top surface part 34A and is further jetted from each upper stage flame hole 30 for combustion. Since the mixed gas uniformized by passing through many small holes 36, 37 flows through each upper stage flame hole 30 and each lower stage flame hole 30, a stabilized and uniformized flame over the entire periphery of the burner head 29 is formed on each flame hole 30.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a petroleum vaporization type liquid fuel combustion apparatus mainly used for oil fan heaters and the like.

[0002]

2. Description of the Related Art A conventional liquid fuel combustion apparatus of this type is shown in FIG.
As shown in FIG. 4, a vaporization electric heater 1 is embedded in the peripheral wall portion, and a bottomed cylindrical vaporization cylinder 4 provided with an air inlet 2 and a fuel nozzle 3 in a part of the peripheral wall portion, and the vaporization cylinder 4 A plurality of flame holes 5 attached to the upper opening of the
5 is divided into upper and lower stages and provided on the peripheral wall 6A, and a cylindrical burner head 6 and the mixed gas vaporized and premixed in the vaporization cylinder 4 are guided into the burner head 6 through a throttle passage 7A provided in the central portion. And a diaphragm plate 7, and
The bottom wall 6B of the burner head 6 placed on the top has a plurality of ventilation holes 8 for guiding the mixed gas passing through the throttle passage 7A of the throttle plate 7 into the burner head 7.

[0003]

In the liquid fuel combustion apparatus having such a structure, the liquid fuel such as kerosene ejected from the fuel nozzle 3 is heated to a high temperature by the vaporization electric heater 1 or combustion heat. In contact with the inner wall surface of the vaporizing cylinder 4, the vaporized gas is premixed in the vaporizing cylinder 4 with the primary air sent into the vaporizing cylinder 4 from the air inlet 2, and this mixed gas is drawn. After flowing into the burner head 6 through the throttle passage 7A and the vent holes 8 in the bottom wall 6B of the burner head 6, the gas is ejected from each flame hole 5 and burns.

By the way, in the liquid fuel combustion apparatus in which the air introduction port 2 is provided in a part of the peripheral wall portion of the vaporization cylinder 4, the air introduction port 2 is used.
The air sent from the inside into the vaporization cylinder 4 swirls along the inner wall surface of the vaporization cylinder 4 and mixes with the vaporized gas, and
When it reaches a place apart from the air inlet 2, it flows toward the throttle passage 7A of the throttle plate 7 from there, and the throttle passage 7A
Pass through. Here, the amount of air of the mixed gas flowing into the throttle passage 8A tends to be larger on the side facing the air introduction port 2 and smaller on the air introduction port 2 side, as indicated by arrows a and b in FIG. Flame hole 5 on the side facing the air inlet 2
From this, a mixed gas with an excessive amount of air that is easy to lift is likely to be ejected, and a mixed gas with an insufficient amount of air that is likely to cause red fire is likely to be ejected from the flame holes 5 on the air introduction port 2 side. As described above, if the flames formed in the burner head flame holes are non-uniform, combustion noise increases and the amount of CO generated increases. Therefore, in the conventional liquid fuel combustion apparatus, as shown in FIG. 7, a large number of vent holes 8, 8 are formed in the bottom wall 6B of the burner head 6 to stabilize and equalize the flame. Further, in a burner head having a throttle passage formed in the bottom wall thereof (for example, Japanese Utility Model Laid-Open No. 61-9230), a pressure equalizing plate having a large number of small holes formed in the lower portion of the burner head is formed so as to cover the throttle passage. The above problems were solved by providing them.

Further, in recent years, the flame holes through which the mixed gas is ejected are small holes of about 3 to 5 mm, and the flame holes are divided into a plurality of upper and lower stages on the peripheral wall of the burner head, so that a large combustion amount can be obtained. The mainstream is one that solves the problems of lifting phenomenon and heat damage to the perforated wire mesh over a wide range from combustion to weak combustion where the combustion amount is extremely small, enabling combustion control in a wide range. In the liquid fuel combustion device having such a configuration, the maximum combustion amount is about 4000
When using a high calorie type of about Kcal / h, it is necessary to increase the flame hole area more than that of a low calorie type of maximum calorific value of about 2500 Kcal / h. The height of the burner head must be increased, and the space inside the burner head becomes wider. Therefore, when the combustion power is reduced by weakening the combustion power, stagnation of the mixed gas occurs near the upper center in the burner head,
There was a concern that a flashback would occur due to this stagnation.
In order to prevent the occurrence of such flashback, it can be solved by incorporating various built-in objects in the burner head, but in that case, the internal structure of the burner head becomes complicated, the number of parts and the number of work steps increase, The cost will be greatly increased.

The present invention has been made in view of the above-mentioned circumstances, and it is possible to reliably prevent the occurrence of a flashback while ensuring the uniformity of the flames formed in the respective flame holes, and moreover, to prevent the occurrence of flashback. It is an object of the present invention to provide a liquid fuel combustion device that does not complicate the structure.

[0007]

According to a first aspect of the present invention, there is provided a vaporization cylinder having an air inlet and a fuel nozzle in a peripheral wall portion, and a flame hole attached to an upper portion of the vaporization cylinder for ejecting a mixed gas. A cylindrical burner head divided into a plurality of upper and lower stages and provided on the peripheral wall, a throttle portion for guiding the mixed gas in the vaporization cylinder into the burner head through a throttle passage provided in the central portion, and the throttle passage of this throttle portion are covered. Is installed in the burner head,
A mixed convex rectifying cylinder having a heavenly cylindrical portion in the central portion and an annular flat surface portion on the lower outer periphery is provided, and the rectifying cylindrical cylinder portion has a top surface portion and an annular flat surface portion, respectively. This is a configuration in which a large number of small holes are provided in the.

According to the second aspect of the present invention, the vaporizing cylinder having the air inlet and the fuel nozzle provided in the peripheral wall portion, and the flame hole, which is mounted on the upper part of the vaporizing cylinder and ejects the mixed gas, are divided into a plurality of upper and lower stages. A cylindrical burner head provided on the peripheral wall, a throttle portion that guides the mixed gas in the vaporization cylinder into the burner head through a throttle passage provided in the central part, and a burner head inside the burner head so as to cover the throttle passage of this throttle portion. And a substantially convex mixing rectifying cylinder having a heavenly cylindrical portion in the central portion and an annular flat surface portion on the lower outer periphery, and the mixing rectifying cylinder includes a ceiling surface portion of the heavenly cylindrical portion and an annular flat surface. A large number of small holes are provided in each of the parts, and the height of the top surface part of the heavenly tubular part is set to be substantially the same as or higher than the uppermost flame hole row of the burner head, and , The height of the annular flat surface is lower than the bottom row of burner heads. It is set Configurations.

[0009]

With this structure, the mixed gas from the vaporizing cylinder passes through the throttle passage of the throttle portion and flows into the substantially convex mixing rectifying cylinder arranged in the burner head. Then, a part of the mixed gas that has flowed into the mixing rectifying cylinder flows toward the lower flame holes through a large number of small holes provided in the annular flat surface portion,
The remaining mixed gas is ejected from each flame hole in the lower stage and burned.
Ascends in the heavenly tubular portion, flows toward the upper flame holes through a large number of small holes provided in the top surface thereof, and ejects from each upper flame hole to burn. Here, since the mixed gas that has been homogenized by passing through a large number of small holes flows in each upper flame hole and each lower flame hole, each flame hole is stable over the entire circumference of the burner head. A uniform flame is formed.

Further, a substantially convex mixing rectifying cylinder is arranged in the burner head, and a large number of small holes for passing the mixed gas are provided on the top surface of the heavenly cylindrical portion of the mixing rectifying cylinder. Even when the height is set to be relatively high, there is no stagnation of the mixed gas in the burner head, and it is possible to prevent flashback even if the combustion amount is adjusted to an extremely small amount of combustion.

Further, the flame can be made uniform and the occurrence of flashback can be prevented and the internal structure of the burner head can be prevented from becoming complicated only by incorporating the one-component mixing and straightening cylinder in the burner head.

According to another aspect of the liquid fuel combustion apparatus of the present invention, the height of the top surface portion of the eccentric cylinder portion of the mixing rectifying cylinder is
It is set to be approximately the same as or higher than the uppermost row of flame holes in the burner head, and the height of the annular flat surface is set lower than the lowermost row of flame holes in the burner head. Not only can the mixed gas be made to flow smoothly into the flame holes in the bottommost row of flame holes through the small holes provided in the flat section, but the burner that has been heated to a high temperature by burning the top surface section of the heavenly cylindrical section It can be brought close to the top plate of the head,
It is possible to raise the temperature of the mixed gas whose temperature has dropped when rising in the heavenly cylindrical portion so that the mixed gas is not liquefied inside the burner head.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings of FIGS. In the figure, 10 is a bottomed cylindrical vaporization cylinder made of aluminum die-cast with an open top. The vaporization cylinder 10 is made of an Al-Mn-based aluminum alloy having excellent heat resistance. An air introduction port 11 opened in a tangential direction of the peripheral wall portion is provided in a part of the peripheral wall portion of 10. 12 is an electric heater for vaporization such as a sheath heater embedded in the upper part of the peripheral wall of the vaporization cylinder 10, and 13 is a primary air cylinder whose one end is connected to the air introduction port 11 of the vaporization cylinder 10. The other end is connected to a casing 17 of a blower 16 having a supply fan 15 driven by a motor 14 built therein.

Reference numeral 18 is a bottomed cylindrical burner case provided on the outer periphery of the vaporization cylinder 10, and 19 is a secondary air pipe for feeding secondary combustion air into the space X between the burner case 18 and the vaporization cylinder 10. The secondary air pipe 19 is connected to the casing 17 of the blower 16 like the primary air cylinder 13. Two
Reference numeral 0 denotes an injection needle-shaped fuel nozzle arranged concentrically with the air introduction port 11 and the one end of the primary air cylinder 13, and this fuel nozzle 20 has its tip ejection port 20A inside the vaporization cylinder 10. Vaporize liquid fuel such as kerosene facing
The other end is a fuel tank 23 through a fuel supply pipe 21 and a fuel pump 22 such as an electromagnetic pump.
It communicates with the inside. Reference numeral 24 is a detachable cartridge tank for supplying liquid fuel to the fuel tank 23.

Reference numeral 25 denotes an aluminum die-cast diaphragm plate fitted and mounted in the upper opening of the vaporizing cylinder 10. This diaphragm plate 25 is made of an Al--Mn-based aluminum alloy having excellent heat resistance like the vaporizing cylinder 10. This diaphragm plate 25 is made
A cylindrical portion 26 that forms the throttle passage 25A is integrally formed in the central portion of the above, and an annular convex portion 27 is integrally raised on the upper surface side of the outer peripheral portion. 28 is a diaphragm plate 25
It is a disc-shaped baffle placed just below the cylindrical portion 26 of
There is a space from the cylindrical portion 26.

Reference numeral 29 denotes a ceiling-shaped cylindrical burner head mounted on the upper portion of the vaporization cylinder 10.
Is a top plate part 29 made by drawing a heat-resistant stainless steel plate.
A and the peripheral wall portion 29B are integrally molded, and the peripheral wall portion 29B has a large number of flame holes 30, 3 for ejecting a mixed gas.
0 is provided. In addition, the plurality of flame holes 30, 30
6, is provided on the peripheral wall portion 29B of the burner head 29 by being divided into upper and lower three stages, and the flame holes 30, 30 of each flame hole row a, b, c are It is formed by a small round hole having a diameter of about 5 mm. Reference numeral 31 denotes one ignition flame hole formed at a position lower than the flame holes 30 of the lower flame hole array c, and this ignition flame hole 31 is formed as a round hole smaller than each of the flame holes 30. . Reference numerals 32 and 32 denote flame hole wire nets provided in close contact with both inner and outer surfaces of the peripheral wall portion 29A of the burner head 29.

Reference numeral 33 denotes a mixed rectifying cylinder arranged in the burner head 29 so as to cover the throttle passage 25A of the diaphragm plate 25 from above. This mixed rectifying cylinder 33 is drawn from the side surface by drawing a heat-resistant stainless steel plate. It is formed in a substantially convex shape when viewed. The mixing rectifying plate 33 has a top surface portion 34A of the dome-shaped cylindrical portion 34 provided in the central portion thereof and an annular flat surface portion 35 provided on the outer periphery of the lower portion, each having a diameter of about 2 mm.
A large number of small holes 36, 36, 37, 37 set in the above are provided, and the peripheral wall portion 34B of the heavenly cylindrical portion 34 is a non-perforated wall.

The heavenly cylindrical portion 34 of the mixing rectifying cylinder 33 is
The diameter is made larger than the diameter of the throttle passage 25A of the diaphragm plate 25,
The height of the top surface portion 34A is set to be substantially the same as the upper flame hole row a of the burner head 29, and the height of the annular flat surface portion 35 is set to be lower than that of the lower flame hole row c of the burner head 29. The throttle plate 25, the burner head 29, and the mixing rectification cylinder 33 are fixed to the vaporization cylinder 10 by a plurality of mounting screws 38.

Reference numeral 39 denotes a combustion ring arranged on the outer circumference of the burner head 29. The combustion ring 39 is made of heat-resistant stainless steel plate and is mounted on the upper end of the vaporization cylinder 10 with screws (not shown). It's stopped. The annular wall 39A of the combustion ring 39 facing the peripheral wall 29A of the burner head 29 is provided with a plurality of vertical slits 40 at a predetermined interval in the circumferential direction. Reference numeral 41 is a flame rod for detecting the presence or absence of the flame F and oxygen concentration, and 42 is an ignition rod, and the tip discharge portion of the ignition rod 42 is opposed to the ignition flame hole 31.
Reference numeral 43 is a combustion cylinder.

In the above structure, the vaporization electric heater 1
When the vaporization cylinder 10 rises above the vaporizable temperature of the liquid fuel by energizing 2, the blower 16 and the fuel pump 22 are operated, liquid fuel is discharged from the fuel nozzle 20 via the fuel supply pipe 21, and the primary air cylinder Air inlet 11 through 13
Primary air for combustion is supplied into the vaporization cylinder 10 from each.

Here, the fuel supplied into the vaporizing cylinder 10 is vaporized by coming into contact with the inner wall surface of the vaporizing cylinder 10, and this vaporized gas is mixed with primary air to form a mixed gas, which is a throttle plate. The mixing rectifying cylinder 3 through the throttle passage 25A of 25
Inflow into 3. A part of the mixed gas flowing into the mixing rectifying cylinder 33 is a large number of small holes 37 of the annular flat surface portion 35,
37 through the lower stage flame hole array c and middle flame hole array d
Flowing toward the flame holes 30 of the above, and ejected from each of these flame holes 30 and 30, and the rest rises in the heavenly cylindrical portion 34, and mixing is promoted in the heavenly cylindrical portion 34 while the top surface portion 34A Toward the top surface portion 34A, a large number of small holes 36, 3
Pass 6. The mixed gas that has passed through the small holes 36, 36 flows along the lower surface of the top plate portion 29A of the burner head 29 to the flame holes 30 of the upper flame hole row a and the flame holes 30 of the middle flame hole row b. Face each other and eject from the flame holes 30. Thus, the mixed gas ejected from each flame hole 30 is ignited by the spark of the ignition rod 42, forms a flame F, and starts combustion.

A burner case 18 is provided through a secondary air pipe 19.
The secondary air sent into the inner space X rises in the space X, flows near the outer periphery of the combustion ring 39, is supplied to the flame F, and promotes secondary combustion. After that, the heat of flame F
When the temperature of the vaporization part of the vaporization cylinder 10 is maintained at the vaporizable temperature of the liquid fuel by the heat recovered by the vaporization cylinder 10 via the combustion ring 39 or directly, the vaporization electric heater 12 Power is stopped, but combustion continues.

According to this embodiment, a substantially convex mixing rectifying cylinder 33 is arranged in the burner head 29 so as to cover the throttle passage 25A of the diaphragm plate 25, and the mixing rectifying plate 33 is provided at the central portion thereof. A large number of small holes 3 each having a diameter of about 2 mm are formed in the top surface portion 34A of the erected cylindrical portion 34 and the annular flat surface portion 35 of the lower outer periphery.
Since 6, 36, 37, 37 are provided, each flame hole 30, 30 of each flame hole array a, b, c provided in the peripheral wall portion 29B of the burner head 29 by being divided into three upper and lower stages, Top part 34
A and a large number of small holes 36, 36, 37, 3 of the annular flat surface portion 35.
Since the homogenized mixed gas flows by passing through 7, a stable and uniform flame F is formed on the entire circumference of the burner head 29 over a wide range from strong combustion to weak combustion, and combustion noise can be suppressed, Generation of CO can be suppressed.

The mixing rectifying cylinder 33 arranged in the burner head 29 has a substantially convex shape in a side view, and the mixing rectifying cylinder 33 is formed.
Top surface portion 34A of the heavenly cylindrical portion 34 provided in the central portion of the
By providing a large number of small holes 36 through which the mixed gas is passed, even when the height of the burner head 29 is increased to a high calorie type having a maximum combustion amount of about 4000 Kcal / h, a large number of top surface portions 34A are provided. The small holes 36 allow the mixed gas to flow near the lower surface of the top plate 29A of the burner head 29. As a result, there is no stagnation of the mixed gas in the burner head 29, and the combustion amount is reduced. 700 Kc
Even if the combustion is adjusted to a very low combustion rate of al / h, it is possible to prevent flashback, and the combustion control range is about 4000 Kcal.
It can be in a wide range from / h to about 700 Kcal / h. Further, the flame can be made uniform and the occurrence of flashback can be prevented only by incorporating the mixing and rectifying cylinder 33, which is one component, in the burner head 29.
The internal structure of is not complicated and the cost increase can be suppressed.

In addition, the mixing rectifying cylinder 33 includes a heavenly cylindrical portion 34.
Since the height of the top surface portion 34A of the burner head 29 is set to be substantially the same as that of the upper flame hole row a of the burner head 29, and the height of the annular flat portion 35 is set to be lower than that of the lower flame hole row c of the burner head 29, The mixed gas can be smoothly flowed to each flame hole 30 of the lower flame hole row c and the middle flame hole row b through the small holes 37 provided in the annular flat surface portion 35, and of course, the heavenly cylindrical portion 34.
Can be brought close to the top plate portion 29A of the burner head 29 that is heated to a high temperature by combustion, and the temperature of the mixed gas whose temperature has dropped when rising in the sky cylinder portion 34 is It is possible to raise again by the top surface portion 34A of the top tube portion 34 and the top plate portion 29A of the burner head 29, so that there is no concern that the mixed gas will be liquefied inside the burner head 29 or the mixing rectifying cylinder 33, and the burner Accumulation of tar inside the head 29 can be suppressed.

In the above embodiment, the mixing rectifying cylinder 3 is used.
Although the height of the top surface portion 34A of the heavenly cylindrical portion 34 in 3 is substantially the same as that of the upper flame hole row a of the burner head 29, it may be set higher than that of the upper flame hole row a.

[0027]

As described above, according to the liquid fuel combustion apparatus of the present invention, the burner head ejects a uniform gas mixture by passing through a large number of small holes from each flame hole to burn the burner. Not only can a stable and uniform flame be formed over the entire circumference of the head and good combustion with less combustion noise can be performed, but even if it is a high calorie type, it is possible to backfire with one mixing rectifier built into the burner head. Can be reliably prevented, the internal structure of the burner head is not complicated, the structure is simple, and a stable combustion state from strong combustion to weak combustion can be obtained.

In the liquid fuel combustion apparatus according to the second aspect, it is possible to prevent the mixed gas from being liquefied inside the burner head or the mixing rectifying cylinder, and to suppress the accumulation of tar inside the burner head.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of a liquid fuel combustion apparatus showing an embodiment of the present invention.

FIG. 2 is likewise an enlarged cross-sectional view of a main part.

FIG. 3 is a sectional view showing an overall configuration of the liquid fuel combustion apparatus, similarly.

FIG. 4 is a plan view of the mixing rectifying cylinder.

FIG. 5 is a half sectional side view of the mixing rectification cylinder.

FIG. 6 is a half sectional side view of the same burner head.

FIG. 7 is a cross-sectional view of a main part of a conventional example.

[Explanation of symbols]

 10 Vaporizing Cylinder 11 Air Inlet Port 20 Fuel Nozzle 25 Throttle Plate (Throttle Portion) 25A Throttle Passage 29 Burner Head 29B Peripheral Wall Part (Peripheral Wall) of Burner Head 30 Flame Hole 33 Mixing Rectifying Tube 34 Helicopter Cylinder 34A Top Surface 35 Ring Flat surface 36 Small hole 37 Small hole

Claims (2)

[Claims] 1. A vaporization cylinder provided with an air inlet and a fuel nozzle on a peripheral wall portion, and a cylinder provided on the peripheral wall, which is attached to an upper portion of the vaporization cylinder and has flame holes for ejecting a mixed gas divided into a plurality of upper and lower stages. -Shaped burner head, a throttle portion that guides the mixed gas in the vaporization cylinder into the burner head through a throttle passage provided in the central portion, and a throttle portion provided in the burner head so as to cover the throttle passage of the throttle portion A substantially convex mixing rectifying cylinder having a heavenly cylindrical portion and an annular flat surface portion on the lower outer periphery is provided, and the mixing rectifying cylinder has a large number of top surface portions and annular planar portions of the heavenly cylindrical portion. A liquid fuel combustion apparatus characterized in that a small hole is provided. 2. A vaporization cylinder having an air inlet and a fuel nozzle on the peripheral wall, and a cylinder provided on the peripheral wall, which is attached to the upper part of the vaporization cylinder and in which flame holes for ejecting a mixed gas are divided into upper and lower stages. -Shaped burner head, a throttle portion that guides the mixed gas in the vaporization cylinder into the burner head through a throttle passage provided in the central portion, and a throttle portion provided in the burner head so as to cover the throttle passage of the throttle portion A substantially convex mixing rectifying cylinder having a heavenly cylindrical portion and an annular flat surface portion on the lower outer periphery is provided, and the mixing rectifying cylinder has a large number of top surface portions and annular planar portions of the heavenly cylindrical portion. Small holes are provided, and the height of the top surface portion of the heavenly cylindrical portion is set to be substantially the same as or higher than the topmost flame hole row of the burner head, and the height of the annular flat surface portion is set. Is lower than the bottom row of burner heads. Liquid fuel combustion equipment to collect.