JPS63273706A - Combustion apparatus - Google Patents

Abstract

PURPOSE:To reduce soot and foul odor at the time of ignition and fire extinction by the reduction in the number of on-off operations of a fuel supply pump when a small amount of hot water is supplied by a method wherein a partition plate is placed in a vaporization cylinder and at the side of the cylinder under the plate, dense air-ports of which arrangement is more dense than that of the other air ports are installed. CONSTITUTION:In response to the reduction in the amount of fuel supply with a fuel supply pump 18, combustion air supplied from the air ports 5a of a vaporization cylinder 5 is reduced, however, the proper amount of air which is necessary for combustion is mainly supplied from dense air-ports 11 placed at the lower air passage 5d of the cylinder 5 and mixed air ports 5e. Rising air-fuel mixture collides with a large amount of air streams ejecting in the radius direction of the ports 11 placed above the passage 5d to burn quickly. The flame holding property at the ports 11 is improved and superior to that at the other ports 5a, 5e by the flame holding force between adjacent flames. Since the ports 11 are installed toward the upper part of an auxiliary combustion cylinder 12, the unburnt part of combustion gas ejecting from the inside of the cylinder 12 is completely burnt by combustion flames 21 formed at the ports 11.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a combustion device used in small household water heaters and the like.

2. Description of the Related Art As shown in FIG. 3, a conventional combustion device of this type has a carburetor 2 erected approximately in the middle of a combustion chamber 1, and a plurality of air cylinders provided on the side of the carburetor 2. A swirling flow is generated in the combustion chamber 1 by the hole 3, and the fuel is sent by a constant pressure of the fuel supply pump 6 from a fuel spray nozzle 5 facing into the combustion chamber 1 from a part of the outer peripheral wall 4 of the combustion chamber 1. The fuel is sprayed and ignited by the ignition device 7. The sprayed fuel 8 flows into an auxiliary combustion tube 10 provided around the vaporization tube 2 through an opening 9, evaporates while receiving heat from the flame 11, and mixes with air to sustain combustion. Ta.

3 Problems to be Solved by the Invention However, in the above configuration, the fuel spray nozzle 5
Since the fuel is sprayed at a constant pressure, the fuel supply pump 6 is turned on in order to reduce the amount of hot water supplied by the water heater in accordance with summer showers.

Since they are used repeatedly on and off, they have problems such as unstable combustion, generation of large amounts of soot and odor, and inability to obtain stable and appropriate water temperatures. The present invention solves such conventional problems by stabilizing the combustion flame when the amount of fuel supplied is reduced by lowering the pressure of the fuel supply pump, promoting combustion, and achieving good combustion. The purpose is to supply hot water at an appropriate temperature in a small amount.

Means for Solving the Problems In order to solve the above problems, the combustion apparatus of the present invention provides a partition plate in the vaporization cylinder, and arranges air holes on the side surface of the vaporization cylinder below the partition plate more densely than other air holes. A densely packed air hole is provided, and mixing air holes are provided sparsely below the densely packed air hole.

Effects of the present invention With the above-described configuration, when the amount of fuel supplied is reduced, air is jetted out intensively at a large rate from the dense air holes, so that a stable combustion flame can be formed, and unburned fuel can be removed. and expand the range of good combustion.
Regardless of the amount of combustion, it maintains good combustion and consistently provides hot water at an appropriate temperature.

Embodiments Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. In Fig. 1 and Fig. 2, 1 indicates the inner shell 2 and the outer shell 3.
A heat exchanger consisting of a combustion chamber 4 located below the inner shell 2.
is provided. A vaporizer cylinder 5 is installed approximately at the center of the bottom surface of the combustion chamber 4, and a plurality of air holes 5a are provided on the side surface of the combustion chamber 4. It is configured so that the swirled air inside the chamber 4 is blown out. In the middle of the inside of the vaporizer cylinder 5, there is a vaporizer cylinder 5.
A partition plate 5b is provided to partition the inside of the vaporizer cylinder 5 into upper and lower parts.
The interior is divided into an upper air chamber 5c and a lower air passage 5d, and from the partition plate 5b, an inner cylinder 6 extending downward and communicating with the upper air chambers 51 and 5c is provided. The vaporizing cylinder 5 is provided in a double configuration with the lower air passage 5d and the lower air passage 5d. Separate air passages 7 are communicated with the inner cylinder 6 and the lower air passage 5d, and an air distributor 8 is provided at the other end of the air passage 7. The air distributor 8 is provided with a ventilation passage 10 from a blower 9. Among the air holes 5a of the vaporization tube 5, dense air holes 11 are provided above the lower air passage 5d, and are arranged more densely than other air holes 5a, and whose opening direction is radial. Further, below the lower air passage 5d, there are provided mixing air holes 5e which are arranged more sparsely than the dense air holes 11 and whose opening direction is substantially tangential. Further, around the vaporizer cylinder 5, there is a vaporizer cylinder. A circumferential auxiliary combustion tube 12 with a shorter height than the auxiliary combustion tube 12 is provided, and a plurality of ventilation holes 12g are provided below the side surface of the auxiliary combustion tube 12, and approximately in the middle of the side surface, air from a fuel spray nozzle 13 is provided. An inlet 12b for the atomized fuel 14 is provided. The upper end of the auxiliary combustion tube 12 is installed lower than the height of the partition plate 5b in the carburetor tube 5, and is installed on the side surface of the lower air passage 5d, which is installed at a lower position than the partition plate 5b. A part of the dense air holes 5e is also provided at a position higher than the upper end of the auxiliary combustion tube 12. The fuel spray nozzle 13 is arranged in a glow tube 16 provided in a through hole 15 provided through the inner cylinder 2 and the outer cylinder 3, and has its tip facing into the combustion chamber 4. The fuel spray nozzle 13 is communicated with a fuel supply pump 18 via a fuel supply pipe 17. The fuel supply pump 18 is designed to be able to change the amount of fuel supplied by varying the fuel supply pressure. The blowchave 16 is also configured to allow air to flow into the air distributor 8 via an air passage 19. An igniter 20 is provided to ignite the fuel 14 sprayed by the fuel spray nozzle 13. 21 is a combustion flame. Further, 22 indicates a swirling air flow, and 23 indicates a high temperature combustion gas flow.

In the above configuration, when the fuel is pumped by the fuel supply pump 18, this fuel is injected in advance into the auxiliary combustion cylinder 12 and into the combustion chamber 4 from the air hole 5a of the carburetor cylinder 5 by the blower 7/machine 9. The atomized fuel 14 collides with and mixes with the swirling air, and is ignited by the igniter 20 by the spark discharge that was formed before the atomized fuel 14 was ejected. Thereafter, it receives radiant heat from the combustion flame 21, and a part of the high-temperature combustion gas descends between the auxiliary combustion tube 12 and the inner shell 2 like a combustion gas flow 23, and is recirculated through the vent hole 12a, thereby becoming atomized. The premixed fuel 14 is evaporated and mixed with swirled air, and the premixed mixture rises inside the auxiliary combustion tube 12 while swirling like a swirling air flow 22, and enters the air hole 5 of the vaporization tube 5.
A combustion flame 21 is formed at an appropriate position of a to continue combustion.

At this time, as the fuel supply amount is reduced by the fuel supply pump 18, the amount of air for combustion from the air hole 5a of the carburetor 5 is reduced, but the appropriate amount of air necessary for combustion is mainly supplied to the carburetor. The air is supplied from the dense air hole 11 and the mixing air hole 5e provided on the side surface of the lower air passage 5d of the vaporizer tube 5, and at the same time, the excess air is supplied from the air hole 5a provided on the side surface of the upper air chamber 5c of the vaporizer cylinder 5. An appropriate amount of air is allowed to flow into the combustion chamber 4.

In this way, the amount necessary for combustion is supplied from the lower air passage 5d side, but the sprayed fuel 14 is supplied from the lower air passage 5d side.
Swirling air flow 22 of the mixing air hole 5e provided below d
As a result, the air and the vapor of the fuel 14 are sufficiently mixed to form a uniform mixture.

Since the mixing air holes 5e are arranged sparsely, an appropriate amount of air for combustion is not yet supplied, so that a more effective air-fuel mixture can be formed while rising inside the auxiliary combustion cylinder 12. The rising air-fuel mixture collides with a large amount of air flow ejected in the radial direction of the dense air holes 11 provided above the lower air passage 5d, and can be combusted at some point. Since the dense air holes 11 are arranged more densely than the other air holes 5a and 5e, flame holding is improved by the flame holding power of adjacent flames, and the range of stable combustion can be expanded. In addition, dense air holes 1
1 is provided toward the upper end of the auxiliary combustion tube 12, so
Complete combustion can be achieved by the combustion flame 21 that forms the unburned remains of the combustion gas 23 ejected from the inside of the auxiliary combustion tube 12 in the dense air holes 11. In this way, even when the amount of fuel supplied is small, a stable combustion flame can be formed and good combustion can be performed, resulting in the effect that stable hot water supply at an appropriate temperature can always be obtained.

Effects of the Invention As described above, the combustion apparatus of the present invention provides the following effects.

(1) Since densely packed flames are provided above the lower air passage of the carburetor cylinder, which are denser than other air hole arrangements, a stable combustion flame is formed due to the flame holding power of adjacent flames, and inside the auxiliary combustion cylinder. This has the effect of completely combusting the unburned remains of the combustion gas that has risen, and expanding the range of good combustion.

? ) Since the mixed air is provided loosely below the lower air passage of the carburetor cylinder, it is possible to raise the air-fuel mixture while forming a uniform air-fuel mixture to the combustion flame that forms in the dense air holes without combusting the air-fuel mixture too early. There is an effect that it can be done.

(3) Even if the fuel supply is small, the amount of air ejected from the dense air holes is relatively large, so the combustion flame can always be formed near the top of the auxiliary cylinder, eliminating unburned remains and maintaining combustion characteristics. There is an effect that it can be done.

(b)) Even if the fuel supply is small, good combustion can be achieved, so there is an effect that stable hot water at an appropriate temperature can be supplied when a small amount of hot water is supplied for showering in the summer or the like.

(5) By reducing the number of times the fuel supply pump is turned on and off when a small amount of hot water is supplied, soot and odor during ignition and extinguishing can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of a combustion device according to an embodiment of the present invention, FIG. 2 is an enlarged sectional view of the same main part, and FIG. 3 is a sectional view of a conventional combustion device. 5... Vaporization cylinder, 5a/ Air hole, 5c - Upper air chamber, 5d... Lower air passage, 5e... Mixing air hole, 11 Dense air hole. Name of agent: Patent attorney Toshio Nakao and 1 other person5-
Vaporizer cylinder - 11 stomatal diagram 2

Claims (3)

[Claims] (1) A carburetor tube installed approximately at the center of the bottom surface of the combustion chamber and provided with numerous air holes on its side surface, and a spray inlet provided approximately concentrically around the carburetor tube, with a spray inlet located on a part of the side surface. , an auxiliary combustion cylinder provided with a plurality of recirculation holes, a partition plate provided inside the vaporization cylinder to partition it in the vertical direction, and an upper air chamber partitioned by the partition plate that communicates with the vaporization cylinder. An inner cylinder inserted into the cylinder, a lower air passage separated from the inner cylinder and provided around it, an air passage provided in communication with each of the inner cylinder and the lower air passage, and the vaporizer. A plurality of dense air holes are arranged more densely than other air holes on the side surface below the position of the partition plate in the cylinder, and a plurality of dense air holes are arranged sparsely below the dense air holes. Combustion device consisting of a mixing air hole. (2) The combustion device according to claim 1, wherein the dense air holes are provided with openings oriented in the radial direction. (3) The combustion device according to claim 1 or 2, wherein the mixing air hole is provided with its opening oriented in the tangential direction.