JP3133636B2 - Liquid fuel combustion device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid fuel combustion apparatus, and more particularly, to the generation of tar at the bottom of a vaporization chamber by suppressing the stagnation of the liquid fuel at the bottom of the vaporization chamber and performing stable combustion. The present invention relates to a vaporization type liquid fuel combustion device used for a petroleum fan heater or the like in which gas accumulation is suppressed.

[0002]

2. Description of the Related Art Generally, in this type of liquid fuel combustion apparatus, liquid fuel ejected and supplied by a fuel nozzle is vaporized inside, and the vaporized gas and combustion air are premixed and supplied to a combustion section. Equipped with a vaporizer.

FIG. 3 shows an example of a conventional liquid fuel combustion apparatus.

FIG. 3A is an explanatory view for explaining the entire structure of a conventional liquid fuel combustion apparatus, and FIG.
FIG. 2 is an explanatory plan view illustrating a conventional liquid fuel combustion apparatus in an enlarged manner with a cross section taken along line AA.

[0005] In FIG. 3, reference numeral 1 denotes a bottomed cylindrical vaporizer having an open top, and a heater 3 made of a sheathed heater is embedded in an upper portion of a peripheral wall 2 of the vaporizer 1. 4
Is an elbow-type primary air pipe through which primary air for combustion flows,
One end of the primary air pipe 4 is connected to a blower 6 via a communication pipe 5. Reference numeral 7 denotes a fuel supply pipe through which a liquid fuel (kerosene) flows. One end of the fuel supply pipe 7 is connected to a fuel tank 9 via a pump 8 such as an electromagnetic pump.
The other end of the fuel supply pipe 7 is connected to the base end of a fuel nozzle 11 whose front end faces the vaporization chamber 10 inside the vaporizer 1, and the liquid fuel flows from the front end of the fuel nozzle 11 to the vaporization chamber 10. Is supplied. The fuel tank 9 is provided with a detachable cartridge tank 12.

Reference numeral 13 denotes an aperture plate disposed at an upper opening in the vaporizer 1. A burner head 14 is fitted and mounted on the upper opening of the vaporizer 1 above the aperture plate 13. A wire mesh 15 is provided on the inner and outer surfaces of the peripheral wall of the burner head 14, and a large number of flame holes 16 are formed. Reference numeral 17 denotes a flame holding plate provided at the upper end of the vaporizer 1;
5 is a baffle board.

Reference numeral 18 denotes a bottomed cylindrical burner case provided on the outer periphery of the carburetor 1 and surrounding the carburetor 1. In the burner case 18, air is supplied from the blower 6 through a secondary air pipe 19. Sent in. Further, the distal end outlet 19A of the secondary air pipe 19 penetrates the peripheral wall of the burner case 18 and faces the inside of the burner case 18, and the inside of the burner case 18 faces the outlet 19A. Is provided with a baffle plate 20.

Next, the vaporizer 1 will be described in detail.
This vaporizer 1 is made of aluminum die-cast,
An air nozzle portion 22 for supplying combustion air having a horizontal air passage 21 through which the fuel nozzle 11 is inserted coaxially is formed on the peripheral wall 2 by integral molding.

Reference numeral 23 in FIG. 3 denotes an ignition electrode for igniting a mixed gas of vaporized gas and air ejected from the flame hole 16;
Reference numeral 24 denotes a flame rod for detecting the ignited flame F and detecting the oxygen concentration.

In the above configuration, when the vaporizer 1 rises to a predetermined temperature by energizing the heater 3, the blower 6 and the pump 8 operate, and the liquid fuel from the fuel nozzle 11 and the primary air pipe 4 Primary air for combustion is supplied into the vaporization chamber 10 through the air nozzle section 22. At this time,
The combustion air is ejected from the air nozzle section 22 into the vaporization chamber 10, and the liquid fuel ejected from the fuel nozzle 11 is brought into particulate form and brought into contact with the vaporization surface of the vaporization chamber 10. The vaporized gas of the liquid fuel vaporized in contact with the vaporized surface is mixed with the primary air for combustion, and the mixed gas enters the burner head 14 through the passage of the throttle plate 13 and is ejected from the flame hole 16. The jetted gas mixture is ignited by the spark discharge of the ignition electrode 23 to form a flame F and start combustion.

[0011]

However, in the above-mentioned conventional structure, the diameter of the fuel particles ejected from the fuel nozzle 11 does not become small, and the collision surface of the ejected fuel is indicated by the arrow (1) in FIG. a, the fuel ejected from the fuel nozzle 11 comes into contact with the vaporizing surface of the vaporizing chamber 10 and vaporizes when the fuel flow rate is large as in the case of strong combustion, but some of the fuel at the collision surface Without being completely vaporized, it flows down to the vaporization chamber bottom 26. For this reason, there is a problem in that a time delay of vaporization occurs, resulting in unstable combustion, and the generation and accumulation of tar at the vaporization chamber bottom 26.

When the fuel flow rate is small as in the case of weak combustion, the flow rate of combustion air becomes small, and the fuel nozzle 11
The fuel ejected from the fuel is hardly atomized, which causes a time delay of vaporization, resulting in unstable combustion and the same problems as in strong combustion.

Further, there is a problem that odor is generated at the time of starting combustion or at the time of stopping combustion due to a time delay of vaporization of the liquid fuel flowing down to the vaporization chamber bottom 26.

The present invention has been made in view of the above-mentioned circumstances, and in a wide range of combustion conditions from strong combustion to weak combustion, unstable combustion is eliminated, and stable combustion is performed. It is an object of the present invention to provide a liquid fuel combustion device that suppresses generation and accumulation of odor and suppresses generation of odor at the time of starting or stopping combustion.

[0015]

The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that a second air nozzle portion different from a swirling flow generated by combustion air ejected from an air nozzle portion in a vaporization chamber. The inventors have found that the above problem can be solved by generating a swirling flow of air ejected from the bottom along the bottom of the vaporization chamber, and have accomplished the present invention.

According to the first aspect of the present invention, the fuel nozzle and the liquid fuel jetted and supplied by the fuel nozzle are internally vaporized, and the vaporized gas and the combustion air are premixed and supplied to the combustion section. A liquid fuel combustion device comprising: a vaporizer that performs combustion, a first air nozzle unit for supplying combustion air provided on a peripheral wall of the vaporizer, and a blower that supplies combustion air to the first air nozzle unit. A liquid fuel combustion apparatus characterized in that a second air nozzle portion is provided on a peripheral wall of a vaporizer between an air nozzle and a bottom of a vaporization chamber to generate a swirling flow of air along a bottom of the vaporization chamber.

According to a second aspect of the present invention, in the liquid fuel combustion apparatus according to the first aspect, the secondary air is divided into a second air and a second air.
It is characterized in that it is supplied to the air nozzle section.

According to a third aspect of the present invention, in the liquid fuel combustion device according to the first or second aspect, air from an air supply device such as an air pump or a fan is supplied to the second air nozzle portion. Features.

According to a fourth aspect of the present invention, in the liquid fuel combustion apparatus according to any one of the first to third aspects, the direction of the swirling flow of the combustion air ejected from the first air nozzle and the second direction are determined.
It is characterized in that the direction of the swirling flow of the air ejected from the air nozzle portion is reversed.

According to a fifth aspect of the present invention, in the liquid fuel combustion apparatus according to the first to fourth aspects, a plurality of second air nozzles are provided.

[0021]

According to the present invention, the swirling flow of air ejected from the second air nozzle portion can be achieved even if part of the fuel ejected from the fuel nozzle cannot be completely vaporized on the collision surface and flows down to the bottom of the vaporization chamber. Exists along the bottom of the vaporization chamber, so that vaporization is promoted and the liquid fuel does not stay at the bottom of the vaporization chamber.

Since the second air nozzle portion is provided at a position lower than the first air nozzle portion and higher than the bottom of the vaporization chamber, a lower portion of the swirling flow of the combustion air ejected from the first air nozzle portion is provided. In addition, a swirling flow of air ejected from the second air nozzle portion is generated along the bottom of the vaporization chamber.

Since these swirling flows diffuse the liquid fuel ejected and supplied from the fuel nozzle, the collision surface of the liquid fuel becomes wide. Further, since these swirling flows mix the vaporized liquid fuel and air, the mixing of both is promoted.

As described above, the vaporized surface of the liquid fuel can be made large, and the liquid fuel flowing down to the bottom of the vaporization chamber is promoted to be vaporized, so that all the liquid fuel ejected from the fuel nozzle is vaporized instantaneously. Unstable combustion due to the vaporization time delay as shown in the example is eliminated, and stable combustion can be performed. This eliminates the problem of tar generation or accumulation at the bottom of the vaporization chamber.

Further, the odor at the time of starting combustion or at the time of stopping combustion, which is generated due to a time delay of vaporization of the liquid fuel, is suppressed.

The mounting position of the second air nozzle portion, the ratio of the cross-sectional area of the outlet of the second air nozzle portion to the cross-sectional area of the first air nozzle portion, the amount and speed of air blown out of the second air nozzle portion, or the blowout There are no particular restrictions on the various combustion-related conditions, such as the swirling direction of the swirling flow of the air ejected from the second air nozzle portion, such as the angle at which the liquid fuel is vaporized, and the liquid fuel vaporized surface can be large, and the liquid fuel that has flowed down to the bottom of the vaporization chamber. Is appropriately determined so that the liquid fuel ejected from the fuel nozzle can be instantaneously vaporized and stable combustion can be performed.

The amount of air ejected from the second air nozzle portion is, for example, an amount capable of promoting the vaporization of the liquid fuel flowing at least to the bottom of the carburetor, and the mounting position of the second air nozzle portion is as low as possible. Preferably it is near the bottom.

The air ejected from the first air nozzle and the second
Since the fuel nozzle is cooled by the air ejected from the air nozzle part and its temperature is lowered, tarring of the fuel remaining in the fuel nozzle and clogging of the tip part can be prevented.

By diverting the primary air and supplying it from the second air nozzle, the above-mentioned conditions can be easily set, and the present invention can be easily and economically performed without largely changing the conventional apparatus. Can be implemented.

By supplying air from an air supply device such as an air pump or a fan from the second air nozzle portion,
Various conditions such as the amount, speed, and angle of air can be easily controlled to an optimum range, and the present invention can be easily and economically implemented without largely changing a conventional device.

By reversing the direction of the swirling flow of the combustion air ejected from the first air nozzle portion and the direction of the swirling flow of the air ejected from the second air nozzle portion, the liquid fuel ejected and supplied from the fuel nozzle is provided. Can be further diffused, the collision surface of the liquid fuel can be widened, and the mixing of the vaporized liquid fuel and the air can be further promoted.

By providing a plurality of second air nozzles, diffusion of liquid fuel and mixing of vaporized liquid fuel and air can be further promoted.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the contents of the present invention will be described more specifically with reference to FIGS. 1 and 2, but the present invention is not limited to these contents.

FIG. 1 is an explanatory view showing a main part of a liquid fuel combustion apparatus according to a first embodiment of the present invention. (1) in FIG.
FIG. 1 is an explanatory view illustrating the overall configuration of a liquid fuel combustion device of the present invention of a type in which a vaporizer 1 and a blower 6 are integrated, and FIG. 1 (2) is a liquid fuel combustion device of the present invention. FIG. 4 is an explanatory plan view illustrating a cross section taken along line BB of FIG.

1 is a vaporizer, 2 is a peripheral wall of the vaporizer 1,
Reference numeral 4a denotes an air hole through which primary air for combustion and secondary air flow. One end of the air hole 4a communicates with the blower 6.
30 is an air filter. The first air nozzle portion 22a and the second air nozzle portion 27 provided on the peripheral wall 2 of the vaporizer 1 are provided substantially facing each other, and a part of the air flowing from the air hole 4a is supplied to the first air nozzle portion 22a. And a part of the air that has flowed in from the air hole 4a is diverted and jetted from the second air nozzle portion 27 into the vaporization chamber 10. Part of the air flowing from the air holes 4a rises through the air holes 4b and becomes secondary air.

The first air nozzle portion 22a is provided at the bottom 26 of the vaporization chamber.
The fuel nozzle 11 is provided so that the center thereof is located at a position H above the fuel nozzle, and the fuel nozzle 11 is coaxially inserted therethrough. The second air nozzle portion 27 is provided so that its center is located at a position h above the vaporization chamber bottom portion 26.

Since H is set to be larger than h, the second air nozzle portion 27 is provided at a position lower than the first air nozzle portion 22a and higher than the bottom portion 26 of the vaporization chamber, and is used for combustion discharged from the first air nozzle portion 22a. A swirling flow (arrow 28) of the air ejected from the second air nozzle portion 27 is formed below the swirling flow of air (arrow 29). The swirling directions of the swirling flow 29 and the swirling flow 28 are the same in this case.

Reference numeral 13 denotes an aperture plate. A burner head 14 is fitted and mounted on the upper opening of the vaporizer 1 above the aperture plate 13. A wire mesh 15 is provided on the inner and outer surfaces of the peripheral wall of the burner head 14, and a large number of flame holes 16 are formed. Reference numeral 17 denotes a flame holding plate provided at the upper end of the vaporizer 1, and 25 denotes a baffle plate.

In the above configuration, when the vaporizer 1 rises to a predetermined temperature by energizing the heater 3, the blower 6 and the pump 8 operate, and the liquid fuel is ejected and supplied from the tip of the fuel nozzle 11 to the vaporization chamber 10. At the same time, air is supplied from the first air nozzle portion 22 a into the vaporization chamber 10, and at the same time, air is ejected from the air into the vaporization chamber 10 from the second air nozzle portion 27.

The liquid fuel ejected from the tip of the fuel nozzle 11 into the vaporization chamber 10 is diffused by the air ejected from the first air nozzle portion 22a, and is diffused by the second air nozzle portion 2a.
The liquid fuel is diffused by the air ejected from 7, so that the collision surface of the liquid fuel becomes large and comes into contact with the vaporization surface of the vaporization chamber 10.

The air ejected from the first air nozzle portion 22a and the air ejected from the second air nozzle portion 27 mix the vaporized liquid fuel with the air, so that the mixing is promoted.

Even if a part of the fuel ejected from the fuel nozzle 11 cannot be completely vaporized on the collision surface and flows down to the vaporization chamber bottom 26,
Since the swirling flow 28 of the air ejected from the second air nozzle portion 27 exists along the vaporization chamber bottom 26, vaporization is promoted, and the liquid fuel does not stay in the vaporization chamber bottom 26.

The liquid fuel has a large vaporized surface, and a part of the liquid fuel cannot be completely vaporized on the collision surface. Even if the liquid fuel flows down to the vaporization chamber bottom 26, the vaporization is promoted, so that the liquid jetted from the fuel nozzle 11 is discharged. All the fuel is instantaneously vaporized, and the vaporized gas is mixed with the primary air for combustion.
The burner head 14 enters the burner head 14 through the passage and is ejected from the flame hole 16 to perform stable combustion.

As described above, the vaporized surface of the liquid fuel can be made large, and all the liquid fuel ejected from the fuel nozzle can be vaporized instantaneously and stable combustion can be performed. Odor at the start of combustion or at the time of stoppage of combustion is suppressed, and the problem of tar generation or accumulation in the vaporization chamber bottom 26 is eliminated.

The fuel nozzle 11 is cooled by the air ejected from the first air nozzle portion 22a and the air ejected from the second air nozzle portion 27, so that the temperature of the fuel nozzle decreases,
Tarring of the fuel remaining in the fuel nozzle 11 and clogging of the tip can be prevented.

FIG. 2 is an enlarged plan view illustrating a part of a carburetor of a liquid fuel combustion apparatus according to a second embodiment of the present invention in an enlarged manner.

The same reference numerals as those in FIG. 1 denote the same components. A first air nozzle portion 22b is provided on the peripheral wall 2 of the vaporizer 1 and a plurality of second air nozzle portions 22b.
Air nozzle portions 27a and 27b are provided. Part of the air that has flowed in from the air hole 4a (not shown) blows out from the first air nozzle portion 22b into the vaporization chamber 10, and part of the air that has flowed in from the air hole 4a (not shown) is diverted to the second air nozzle portion 27a and The gas is ejected from 27b into the vaporization chamber 10.

The second air nozzles 27a and 27b are provided at a position lower than the first air nozzle 22b and higher than the bottom 26 of the vaporization chamber. And the first air nozzle unit 2
A swirling flow (arrows 29b and 29c) of the air ejected from the second air nozzle portions 27b and 27a is formed below the swirling flow of the air ejected from the 2b (arrow 29a).

The liquid fuel ejected from the tip of the fuel nozzle 11 into the vaporization chamber 10 is diffused by the air ejected from the first air nozzle portion 22b and is diffused by the second air nozzle portion 2b.
The liquid fuel is diffused by the air ejected from 7a and 27b, so that the collision surface of the liquid fuel becomes larger and comes into contact with the vaporization surface of the vaporization chamber 10.

The gas ejected from the first air nozzle portion 22b and the air ejected from the second air nozzle portions 27a and 27b mix the vaporized liquid fuel with the air, so that the mixing is further promoted.

Even if part of the fuel ejected from the fuel nozzle 11 cannot be completely vaporized at the collision surface and flows down to the vaporization chamber bottom 26 (not shown), the swirling flow 29c of the air ejected from the second air nozzles 27a and 27b And 29b are present along the vaporization chamber bottom 26 (not shown), so that vaporization is promoted,
The liquid fuel does not stay in the vaporization chamber bottom 26 (not shown).

The liquid fuel has a large vaporizing surface, and a part of the liquid fuel cannot be completely vaporized on the collision surface. Even if the liquid fuel flows down to the vaporization chamber bottom 26 (not shown), the vaporization is promoted, so that the fuel nozzle 11 All of the ejected liquid fuel is instantaneously vaporized, and the vaporized gas is mixed with air. This mixed gas enters the burner head 14 (not shown) through the passage of the throttle plate 13 (not shown), and passes through the flame hole 16 (not shown). Spouting and stable combustion can be performed.

As described above, the vaporized surface of the liquid fuel can be made large, and all of the liquid fuel ejected from the fuel nozzle can be vaporized instantaneously and stable combustion can be performed. The odor generated at the start of combustion and at the time of combustion stoppage is further suppressed, and the vaporization chamber bottom 2 (not shown)
The problem of tar generation and accumulation is eliminated.

The fuel nozzle 11 is cooled by the air ejected from the first air nozzle portion 22b and the air ejected from the second air nozzle portions 27a and 27b, so that the temperature of the fuel nozzle decreases and remains in the fuel nozzle 11. Fuel tarring and clogging of the tip can be prevented.

[0055]

As described above, the present invention is constructed as described above, and therefore, in a wide range of combustion from a strong combustion to a small fuel flow rate, for example, part of the fuel ejected from the fuel nozzle cannot be completely vaporized on the collision surface. Even if the fuel flows down to the bottom of the vaporization chamber, vaporization is promoted by the swirling flow of air ejected from the second air nozzle generated along the bottom of the vaporization chamber, and the liquid fuel does not stay at the bottom of the vaporization chamber.

Since the liquid fuel jetted and supplied from the fuel nozzle is diffused by the swirling flow of the air jetted from the first and second air nozzles, the collision surface of the liquid fuel becomes wide and
Since these swirling flows mix the vaporized liquid fuel and air, the mixing is promoted.

As described above, the vaporized surface of the liquid fuel can be made large, and the liquid fuel flowing down to the bottom of the vaporizing chamber is promoted to be vaporized, so that all the liquid fuel ejected from the fuel nozzle is vaporized instantaneously. Unstable combustion due to the vaporization time delay as shown in the example is eliminated, and stable combustion can be performed. Further, the odor at the time of starting combustion or at the time of stopping combustion, which is generated due to the time delay of vaporization of the liquid fuel, is suppressed, and the problem of tar generation or accumulation at the bottom of the vaporization chamber is eliminated.

The fuel nozzle is cooled by the air from the first and second air nozzles which are supplied into the vaporization chamber and the temperature thereof is reduced. Therefore, the fuel remaining in the fuel nozzle is tarred and the tip is clogged. Can be prevented.

By diverting the primary air and supplying it from the second air nozzle, it is easy to set various combustion-related conditions and easily and economically without greatly changing the conventional apparatus. Can be implemented.

By supplying air from an air supply device such as an air pump or a fan from the second air nozzle portion,
Various conditions relating to combustion can be easily controlled to an optimum range, and the present invention can be easily and economically implemented without largely changing a conventional apparatus.

By reversing the direction of the swirling flow of the combustion air ejected from the first air nozzle portion and the direction of the swirling flow of the air ejected from the second air nozzle portion, the liquid fuel ejected and supplied from the fuel nozzle is provided. Can be further diffused, the collision surface of the liquid fuel can be widened, and the mixing of the vaporized liquid fuel and the air can be further promoted.

By providing a plurality of second air nozzles, diffusion of liquid fuel and mixing of vaporized liquid fuel and air can be further promoted.

The liquid fuel combustion apparatus of the present invention has a simple structure, is economical, and has a large effect, and therefore has high industrial utility value.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part of a liquid fuel combustion apparatus showing one embodiment of the present invention.

FIG. 2 is an explanatory plan view illustrating a part of a carburetor of a liquid fuel combustion apparatus according to another embodiment of the present invention by enlarging the cross section in section.

FIG. 3 is an overall configuration diagram of a conventional liquid fuel combustion device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vaporizer 2 Perimeter wall 3 Heater 4 Primary air pipe 4a, 4b Air hole 5 Connecting pipe 6 Blower 7 Liquid fuel supply pipe 8 Pump 9 Fuel tank 10 Vaporization chamber 11 Fuel nozzle 12 Cartridge tank 13 Throttle plate 14 Burner head 15 Wire net 16 Flame hole 17 Flame holding plate 18 Burner case 19 Secondary air pipe 20 Baffle plate 21 Air passage 22 Air nozzle portion 22a, 22b First air nozzle portion 23 Ignition electrode 24 Frame rod 25 Baffle plate 26 Evaporation chamber bottom 27, 27a, 27b 2nd air nozzle part 28, 29, 29a, 29b, 29c Swirling flow 30 Air filter

Continuation of front page (56) References JP-A-5-44911 (JP, A) JP-A-4-332305 (JP, A) JP-A-4-316905 (JP, A) JP-A-4-116316 (JP) JP-A-62-258905 (JP, A) JP-A-2-45319 (JP, U) JP-A-48-95223 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB Name) F23D 11/10 F23D 11/40-11/44

Claims (5)

(57) [Claims] 1. A fuel nozzle, a vaporizer for internally vaporizing liquid fuel ejected and supplied by the fuel nozzle, and premixing the vaporized gas and combustion air to supply the mixture to a combustion section; A first air supply for combustion air provided on the peripheral wall
In a liquid fuel combustion device including an air nozzle unit and a blower for feeding combustion air to the first air nozzle unit,
A liquid fuel combustion device, comprising: a second air nozzle portion provided on a peripheral wall of a vaporizer between an air nozzle portion and a bottom portion of a vaporization chamber to generate a swirling flow of air along a bottom portion of the vaporization chamber. 2. The liquid fuel combustion apparatus according to claim 1, wherein the primary air is divided and supplied to the second air nozzle. 3. The liquid fuel combustion device according to claim 1, wherein air from an air supply device such as an air pump or a fan is supplied to the second air nozzle portion. 4. The method according to claim 1, wherein the direction of the swirling flow of the combustion air ejected from the first air nozzle portion and the direction of the swirling flow of the air ejected from the second air nozzle portion are reversed. Item 4. The liquid fuel combustion device according to Item 3. 5. The liquid fuel combustion apparatus according to claim 1, wherein a plurality of second air nozzles are provided.