JPH03158608A - Burner - Google Patents

Abstract

PURPOSE:To prevent the blowoff of the burning flame above the end section of a flame hole and deterioration in the exhaust gas characteristics by providing a flow straightening board which has a plurality of through-holes below the end section of the flame hole through a gap. CONSTITUTION:In the upper section of a mixing chamber 34 a multi-hole type flame holes 38 which are divided by a plurality of secondary air blowout chambers 37 is provided, and flow straightening boards 42 are provided below both ends of the flame hole 38 through a gap 41, and part of the board 42 is provided with a plurality of through-holes 43. Now, when the mixture of the vaporization gas that is carried out from a carburetor 8 and the carrier air from a carrier air channel 33 becomes insufficient because of the variability in the performances, etc., of a blower 31 and a fuel supply pump 27, and a change in the ambient temperature and so on, and when a low density mixture gas ascends along the inner wall of the mixing chamber 34, it receives resistance by the flow straightening board 42 and the mixing is again promoted. At the same time since the flow rate of the mixture gas falls further as it gets nearer to the end section of the flame hole 38 by the through-holes 43, the combustion flame 17 adheres to the flame hole 38 tightly, raising the temperature of the flame hole 38 and making it possible to stabilize the flame holding. As a result the combustion flame 17 does not develop blowoff with excessive air and it is possible to prevent the deterioration in the exhaust gas characteristics such as the generation of carbon monoxide and irritating odor.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a combustion device used in household water heaters and the like.

BACKGROUND OF THE INVENTION Conventionally, this type of combustion apparatus has had a structure as shown in FIG.

That is, 1 is a heater, 2 is a vaporizer cylinder, 3 is a vaporizer cylinder lid, 4
is a flame hole plate, 5 is a flame hole net, 6 is a flame hole cap, 7 is a rotor, 8 is a swinging plate, 9 is a mixing blade, IO is a fuel supply pipe, 11 is a heat insulator, 12 is a combustion fan, 13 is a motor ,
14 is a fuel supply pump, 15 is an oil receiving tank, and 16 is a vaporization surface.

When the heater 1 is energized and the temperature of the vaporizer tube 2 rises to a predetermined temperature, the motor 13 is driven, and the rotor 7, swing plate 8, mixing blade IU9, and combustion fan 12 rotate.

On the other hand, fuel is supplied to the oil receiving tank 1 by the fuel supply pump 14.
The fuel is pumped up from the rotor 7 through the fuel supply pipe 10.
Due to the centrifugal force of the rotor 7 and the swinging plate 8, which rotate while being supplied to the top, the water is uniformly scattered from the outer circumference of the swinging plate 8 and is atomized. The atomized fuel is vaporized on the vaporization surface 16 of the inner wall of the heated vaporization cylinder 2, and is mixed with combustion air supplied by the combustion fan 12.
It becomes a mixture.

The air-fuel mixture is mixed more uniformly by the rotating mixing vane 9, and is ejected from the flame hole net 5 through the vaporizing tube cover 3 and flame hole plate 4, and is ignited by an igniter (not shown) to be combusted.

Thereafter, the upper outer periphery of the vaporizer tube 2 and the upper surface of the vaporizer tube lid 3 receive the heat of the combustion flame 17 and transfer it to the vaporizer surface 1G to promote vaporization, so that the heater is de-energized.

Problems to be Solved by the Invention However, with such a structure, there is a problem that due to variations in the combustion fan 12 and the fuel supply pump 14, when combustion reaches an excess air state, the combustion flame 17 is blown away, deteriorating the exhaust gas characteristics. there were.

That is, when the air-fuel mixture has excess air, the combustion flame 17 is cooled by the excess air, resulting in poor combustion and failure to hold the flame. In particular, the end of the flame hole plate 4 in contact with the vaporizer tube II3 was cooled considerably, and the combustion flame 17 was easily blown away.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to maintain flame stability of the combustion flame stably and to prevent deterioration of exhaust gas characteristics even if combustion becomes excessively airy due to variations in performance of combustion fans and fuel supply pumps.

Means for Solving the Problems and In order to achieve the above object, the present invention provides a current plate having a plurality of through holes below the end of the flame hole with a gap therebetween.

Operation The combustion apparatus of the present invention, with the above configuration, prevents the combustion flame on the end of the flame hole from being blown away, thereby preventing deterioration of exhaust gas characteristics.

EXAMPLE Hereinafter, an example of the present invention will be described based on the accompanying drawings.

In FIGS. 1 and 2, IS is a carburetor with a built-in heater 19, and the upper part of this carburetor 18 has an air-fuel mixture outlet 20.
is provided, and a vaporizing air supply 21 is provided below it. Through this vaporizing air inlet 21, the vaporizer 1
A cutting plate 22 using a flat disc and a conical rotor 23 are provided within the rotor 8 . The swinging plate 22 and rotor 23 are
A motor shaft 24 and a motor 25 are connected. Rotor 2
One end of a fuel supply pipe 26 is placed close to the lower side of the fuel supply pipe 3 with a gap therebetween, and the other end is connected to a fuel supply pump 27 . Further, a carburetor cover 29 is provided around the carburetor 18 via a heat insulating material 2B. A mixture outlet 20 and a vaporizing air inlet 21 are provided to penetrate through the heat insulating material 28 and the vaporizer cover 29. A primary air chamber 30 is provided around the carburetor cover 29, and this primary air chamber 30 is connected to an air passage 32 communicating with a blower 31.

It is separated from the carburetor 18 through a conveying air passage 33 that is provided with a gap above the air-fuel mixture outlet 20 of the carburetor 1B and the surrounding carburetor cover 29 and communicated with the primary air chamber 30. A mixing chamber 34 is provided. A mixture port 35 is provided at the bottom of the mixing chamber 34 at a position facing the mixture outlet 20 of the carburetor 18 . A plate-shaped mixing plate 36 is provided in the mixing chamber 34 above the air-fuel mixture inlet 35 . A plurality of secondary air jetting passages 3 are provided in the upper part of the mixing chamber 34.
A porous flame hole 38 made of a punched plate or the like divided by 7 is provided. The upper ends of the secondary air jetting passage 37 and the flame hole 38 are connected in a substantially planar manner. The secondary air jetting passage 37 is provided in a configuration that does not communicate with the mixing chamber 34, and is communicated with a secondary air passage 39 that is provided around the mixing chamber 34 and communicates with the primary air chamber and the conveying air passage 33. There is. A plurality of secondary air jet holes 40 are provided at the upper part of the secondary air jet passage 37 . Further, a current plate 42 is provided below both ends of the flame hole 38 with a gap 41 in between, and a plurality of through holes 43 are provided in a part of the current plate 42. This through hole 43 is a through hole 4 provided on the side of the secondary air passage 39.
3, the opening diameter is gradually made smaller. 44 is a combustion flame.

Next, the operation of the configuration of this embodiment will be explained. First, by operating the fuel supply pump 27, fuel is supplied to the rotor 23 through the fuel supply pipe 26, and as the motor 25 rotates, the fuel rises along the conical side surface of the rotating rotor 23 via the motor shaft 24. It is atomized and scattered from the shaker plate 22, and is vaporized on the side wall heated by the heater 19 of the vaporizer 18. This vaporized gas is carried out from the air-fuel mixture outlet 20 when vaporizing air flows in from the air passage 32 from the vaporizing air port 21 of the carburetor 18 . Most of the air passes through the air passage 32 from the blower l131 and is divided into conveying air and secondary air. The air for conveyance flows from the conveyance air passage 33 into the mixture inlet 35 of the mixing chamber 34 together with the vaporized gas carried out from the mixture outlet 20 of the carburetor 18, and is mixed by the mixing plate 36 with the air for conveyance and the vaporized gas. The mixing of the
The secondary air 45 flows upward around the mixing chamber 34 and is ignited by an igniter (not shown) to cause combustion.
Flows from the secondary air passage 39 into the secondary air jetting passage 38,
The secondary air is ejected from the secondary air ejection hole 40, enveloping the combustion flame 44 formed in the flame hole 38, shortening the flame length, and promoting high-load combustion.

At this time, the mixing of the vaporized gas carried out from the air-fuel mixture outlet 20 of the carburetor 18 and the conveying air flowing in from the conveying air passage 33 may cause variations in the performance of the air blower @ 31 and the fuel supply pump 27, etc. Due to a state of excess air caused by a change in air temperature, etc., the air becomes insufficient and a lean air-fuel mixture rises along the inner wall of the mixing chamber 34. However, the baffle plate 42 encounters resistance and mixing is promoted again, and the through holes 43 weaken the flow velocity of the air-fuel mixture toward the ends of the flame hole 38, so that the combustion flame 17 does not come into close contact with the flame hole 38. , flame hole 38
The temperature can also be raised to further stabilize flame holding.

As a result, even if there is an excess of air, the combustion flame 17 remains stable and does not blow off, making it possible to prevent deterioration of exhaust gas characteristics such as the generation of carbon oxides and irritating odors. In addition, since the stable combustion range can be expanded, the accuracy of the combustion fan 31 and fuel supply pump 27 can be relaxed.
Management can be made into a container.

Effects of the Invention As described above, the present invention provides a baffle plate having a plurality of through holes below the end of the flame hole with a gap therebetween, so that the combustion device is prevented from being in an excessive air condition due to variations in the blower, etc. Even when the combustion flame is heated, the flame stability of the combustion flame on the end of the flame hole is improved, the combustion flame is prevented from being blown away, and the deterioration of the exhaust gas characteristics is prevented.

[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 a side sectional view of the same combustion device, and FIG. 3 is a sectional view of a conventional combustion device. 34...Mixing chamber, 37...Secondary air jetting passage, 38...Flame hole, 39...Secondary air passage, 30...・Secondary air outlet, 41...
... Gap, 42 ... Current plate, 43 ...
...Through hole.

Claims (1)

[Claims] A mixing chamber is provided above the fuel vaporization means via a primary air passage, a porous flame hole is provided above the mixing chamber, and the flame hole is divided into a plurality of pieces. ,
and a plurality of secondary air jetting passages that do not communicate with the mixing chamber, a plurality of secondary air jetting holes provided at the upper end of the secondary air jetting passages, and a plurality of secondary air jetting holes provided around the mixing chamber,
A combustion device comprising a secondary air passage communicating with an end of the secondary air jetting passage, and a baffle plate having a plurality of through holes provided below the end of the flame hole with a gap therebetween.