JPH0216097Y2 - - Google Patents

Description

[Detailed explanation of the invention] [Purpose of the invention] (Industrial field of application) This invention relates to a primary premixed gas burner for domestic water heaters. This invention relates to an all-primary premixed gas burner for a domestic hot water heater, which is capable of uniformly sending mixed gas to the entire combustion flame face plate, eliminates the outflow of combustion gas, etc. to the outside, and reduces costs. .

[Prior Art] As a conventional all-primary premixing type gas burner, for example, there is a gas instantaneous water heater proposed in Japanese Utility Model Application Publication No. 146250/1983.

This gas instantaneous water heater is constructed so that all the air necessary for combustion is mixed in advance when the fuel gas is sent to the burner using a so-called Shirotzkov fan, which is a type of centrifugal blower.

(Problems to be solved by the invention) <Problems with the conventional technology> However, in this gas instantaneous water heater, the fan case of the centrifugal blower and the burner case that covers the burner etc. are separate pieces. The pressure equalizing part cover of the pressure equalizing part that sufficiently mixes fuel gas and air and uniformly disperses it to the burner, the burner cover, and the fan case are all separate parts. Most of the types are formed by These separate cases are connected and hermetically sealed via a flange joint, or by welding or adhesion.

Further, as shown in FIGS. 4 and 5, in the centrifugal blower 31 itself, the case that covers the fan 35 rotated by the motor 34 is made up of multiple members such as a fan case 32, a fan cover 33, etc. It is formed by joining press-formed products by screwing, caulking, spot welding, etc.

Therefore, in order to prevent the mixed gas of air and fuel gas or combustion gas from leaking outside, it is necessary to insert packing at each joint, or to seal the entire surface by welding or gluing as described above. gender must be ensured. As a result, manufacturing costs increase significantly. On the other hand, when trying to shorten the distance from the fuel gas supply nozzle to the combustion flame face plate in order to downsize the water heater, the mixing of air and fuel gas becomes more difficult. The stability and uniformity of the flame cannot be maintained. In particular, in the case of all-primary premixed gas burners, the entire amount of air required for combustion is mixed in beforehand when the fuel gas is supplied, so even if the space between the flame port and the heat exchanger is small, However, if a sufficient space is not secured for the pressure equalization section, it will not be possible to achieve a sufficient mixing state and to uniformly send the mixed gas to the combustion flame face plate, which is a big problem in terms of miniaturization. It's summery. In addition, since the mixed gas of air and fuel gas sent out by the centrifugal blower has a high positive pressure, it is necessary to ensure that the burner case is sufficiently sealed, but as mentioned above, if there are many connecting parts, Another problem was that there were many accidents caused by gas leaks.

Furthermore, when packing is interposed in the connecting portion, heat conduction is inhibited at the connecting portion since the packing itself has almost no excellent thermal conductivity. As a result, the packing is severely damaged and has poor durability, which necessitates the use of expensive packing with excellent heat resistance, which leads to a problem of increased costs.

<Technical Issues> Therefore, in view of the above-mentioned problems, this invention aims at simplicity and miniaturization, and also allows the mixed gas of air and fuel gas to be sent uniformly to the entire combustion flame face plate. Moreover, it was devised to eliminate the seams of the case that covers the whole to eliminate the outflow of combustion gas and the like to the outside, and to reduce costs.

[Structure of the invention] (Means for solving the problem) This invention consists of a centrifugal blower, a gas supply nozzle arranged in the air intake part of the centrifugal blower, and air and fuel sent out from the air outlet of the centrifugal blower. A centrifugal blower is used in the all-primary premixed gas burner for domestic water heaters, which consists of a pressure equalization section that further agitates and disperses the mixed gas and equalizes the pressure, and a combustion flame face plate that burns the mixed gas from the pressure equalization section. The rotating shaft of the fan is arranged so that its axis intersects the combustion flame face plate at a substantially right angle, and a burner case that covers the entire gas burner is formed almost integrally,
The burner case around the fan of the centrifugal blower,
The gas supply nozzle is formed in a roughly tangled shape that widens toward the combustion flame face plate, and is arranged so as to blow out the fuel gas into the air flow from the air intake part, and the gas supply nozzle is arranged so as to blow out the fuel gas into the air flow from the air intake part. The above-mentioned problem is solved by locating the negative pressure part of the fan of the centrifugal blower within the introduction opening for the mixed gas.

(Function) In the all-primary premixed gas burner for a domestic water heater according to this invention, the rotating shaft of the fan of the centrifugal blower is arranged so that its axis intersects the combustion flame face plate at a substantially right angle, A pressure equalizing section prevents the mixture of air and fuel gas, which is sucked into the combustion flame face plate by a fan of a centrifugal blower and sent out approximately parallel to the combustion flame face plate, from becoming non-uniform. Do it like this.

Then, a burner case that covers the entire gas burner is formed almost integrally, and the fan is positioned within the introduction opening for a mixed gas of air and fuel gas in the burner case, and the gas is sent out in the centrifugal direction by the fan. The mixed gas is fed to the combustion flame face plate by its high positive pressure and burned in a state where the entire burner case is integrated, no outflow to the outside is eliminated, and heat dissipation is excellent.

In addition, the burner case surrounding the fan of the centrifugal blower is formed into a roughly bulging shape that widens toward the combustion flame face plate, so that the burner case is drawn in by the fan of the centrifugal blower and the combustion flame is drawn in by the fan of the centrifugal blower. The flow of air sent out approximately parallel to the mouth face plate collides with the approximately rump-shaped part, spreads over a wide range, and is sent to the combustion flame face face plate while being stirred. Further, the gas supply nozzle is disposed so as to blow out the fuel gas into the air flow from the air intake section, and mixes the fuel gas and air while ensuring a sufficient amount of air.

(Embodiments) Hereinafter, embodiments of this invention will be described with reference to the drawings.

That is, the reference numeral 1 shown in the figure is an all-primary premixing type gas burner in a domestic water heater;
A centrifugal blower 2, a gas supply nozzle 4 arranged in an air intake part 3 of the centrifugal blower 2, and a mixed gas of air and fuel gas sent out from the centrifugal blower 2 are distributed at equal pressure by a porous dispersion plate 5. It consists of a pressure equalization section 6 and a combustion flame face plate 7 that burns the fuel gas from the pressure equalization section 6, and these are arranged in order from the bottom to the top. Covered by case 8.

The burner case 8 has a substantially tupular shape in which at least a portion around the fan 10 of the centrifugal blower 2 expands toward the combustion flame face plate 7. That is, a narrowed portion 9 is integrally formed so as to narrow toward the lower air intake portion 3, and this portion is used as an introduction opening for a mixed gas of air and fuel gas. Only the fan 10 of the centrifugal blower 2 is located within the narrowed portion 9, and the motor 11 is located outside the burner case 8. In other words, a negative pressure section is located within this narrowed portion 9. Moreover, Juan 10
The axis of the rotating shaft 12 is arranged to be perpendicular to the combustion flame face plate 7, that is, to intersect at an angle of 90 degrees. In this case, the air intake part 3 is located between the fan 10 of the centrifugal blower 2 and the motor 11, and for example, the area from the opening of the narrowed part 9 to the motor 11 side is covered with a cover, and an appropriate opening is made there. It is provided as an air intake part 3. In this case, the cover may be integrated with the motor case instead of being separate.

In addition, the code|symbol 14 in a figure is an ignition heater, and 15 is a heat exchanger.

The gas burner 1 formed in this manner has the axis of the rotating shaft 12 of the fan 10 perpendicular to the combustion flame face plate 7, so that the flow of the mixed gas of air and fuel gas sent out by the fan 10 is improved. so that it is approximately parallel to the combustion flame port face plate 7.

Since the burner case 8 is narrowed downward, the mixed gas sent out substantially parallel to the combustion flame face plate 7 collides with the inclined inner wall 13 of the burner case 8 and moves toward the combustion flame face plate 7. flows to In this case, compared to sending the mixed gas directly toward the combustion flame face plate 7, the mixed gas is spread and uniformly dispersed over the entire combustion flame face plate 7. Therefore, the pressure equalizing section 6
Even if the number of porous dispersion plates 5 is small, the pressure equalization section 6
It fulfills the role of In fact, the number of porous dispersion plates 5 can be reduced by several pieces compared to the conventional all-primary premix type gas burner. Moreover,
By locating the fan 10 within the narrowed portion 9, a negative pressure portion exists within the narrowed portion 9, so that no gas leaks from the air intake portion 3.

In addition, the burner case 8 having such a shape can be easily manufactured in one piece by forming it by drawing, etc. If it is formed in one piece, even if a high positive pressure is applied, the mixed gas will not be able to escape from the outside. There is no need to worry about it leaking.
Furthermore, the burner case 8 itself is also heated due to the high heat generated by combustion in the combustion flame face plate 7, but in this case as well, since the burner case 8 is integrally formed, heat conduction due to packing is reduced. Since there is no interference and heat is dissipated throughout, there is no localized high temperature. Further, since it is integrated, there is no need for packing, so there is no need to consider damage to the packing caused by high heat, and it can be formed at low cost.

Furthermore, since a spiral snail-shaped case unlike a conventional gas instantaneous water heater is not required, the structure of the centrifugal blower 2 is also greatly simplified and miniaturized.
The introduction opening for the mixed gas can also be made large.

Note that the axis of the fan 10 and the combustion outlet face plate 7
Although the same effect can be achieved even if the intersection angle is not 90 degrees as described above, it is preferable to make it as close to 90 degrees as possible. However, in some cases, even if the axes of 7 and 10 are parallel, the burner case 8
If the structure of is changed appropriately, the same effects as described above can be obtained.

On the other hand, if the burner case 8 is box-shaped without a narrowed part, for example, as shown in FIG. 21 is attached to the opening of the lower surface of the burner case 8 through a connecting flange 22 with a packing 24 interposed therebetween, so that the burner case 8 is almost integrated. Then, the fan 1 of the centrifugal blower 2 is placed in the narrowed portion 23 on the small diameter opening side, as described above.
Even if only 0 is located, the same effect as described above is achieved.

In this case, the packing 24 includes a heat generating portion,
In other words, since it is used at a position that is least affected by heat relative to the flame opening, there is no need for expensive packing with particularly excellent heat resistance. Further, even in response to high internal positive pressure, the pressure builds up on the end face of the packing, and the width direction becomes the sealing pressure direction, so that a sufficiently sealed state can be maintained.

[Effects of the invention] This invention configured as described above has two centrifugal blowers.
The gas supply nozzle 4 arranged in the air intake part 3 of the centrifugal blower 2 and the fan 10 of the centrifugal blower 2 stir and disperse the mixed gas of air and fuel gas that is sent out from the blowing outlet. In an all-primary premixed gas burner for a household water heater, which is composed of a pressure equalizing section 6 that equalizes the pressure and a combustion flame face plate 7 that burns the fuel gas from the pressure equalizing section 6, the rotation of the fan 10 of the centrifugal blower 2 The shaft 12 is arranged so that its axis is substantially perpendicular to the combustion flame face plate 7, and the burner case 8 that covers the entire gas burner 1 is formed almost integrally, and the fan 1 of the centrifugal blower 2
The burner case 8 around the burner case 8 is formed into a roughly tuppy shape that widens toward the combustion flame face plate 7, and the gas supply nozzle 4 blows out fuel gas into the air flow from the air intake part 3. The fan 10 of the centrifugal blower 2 is placed in the inlet opening of the burner case 8 for introducing a mixed gas of air and fuel gas.
By locating the negative pressure section, the flow of the mixed gas of air and fuel gas sent out by the fan 10 is brought into a state at an appropriate angle with respect to the combustion flame face plate 7. The mixed gas thus sent out at an appropriate angle with respect to the combustion flame face plate 7 flows in the direction of the combustion flame face plate 7 due to the high positive pressure generated by the centrifugal blower 2 . In this way, the mixed gas can be uniformly dispersed throughout the combustion flame face plate 7, as compared with the case where the conventional Shiritzko fan is directly sent to the combustion flame face plate 7. Therefore, the porous dispersion plate 5 of the pressure equalization section 6
The number of sheets can be reduced compared to the conventional one, which makes it possible to reduce the size accordingly and contribute greatly to cost reduction.

Further, the burner case 8 having such a shape can be easily manufactured in one piece by forming it by drawing or the like. If they are formed almost integrally, there is no fear that the mixed gas will leak to the outside even under high positive pressure. Then, a fan 10 is inserted into the narrowed part 9.
There is no gas leakage from the air intake part 3 because the negative pressure part is located there.

Furthermore, the burner case 8 itself is also heated due to the high heat generated by combustion in the combustion flame face plate 7, but in this case as well, since the burner case 8 is integrally formed, heat conduction due to packing is reduced. Since there is no interference and heat is dissipated throughout, there is no localized high temperature. Further, since it is integrated, there is no need for packing, so there is no need to consider damage to the packing caused by high heat, and it can be formed at low cost.

In addition, the burner case 8 surrounding the fan 10 of the centrifugal blower 2 is formed into a substantially tupular shape that expands toward the combustion flame face plate 7, so that the burner case 8 surrounding the fan 10 of the centrifugal blower 2 can be The flow of air that is sucked in and sent out approximately parallel to the combustion flame face plate 7 is spread over a wide area by colliding with the roughly rasp-shaped part, stirring while stirring the combustion flame face plate 7. so you can send it to
Since a stirring effect can also be obtained in that part, it is possible to stir the air and fuel gas so that the mixture as a whole becomes very good. Further, the gas supply nozzle 4 is arranged so as to blow out the fuel gas into the air flow from the air intake part 3, so that the fuel gas and air can be mixed while ensuring a sufficient amount of air. It is.

As a result, since the air and fuel gas are mixed to some extent (close enough) before reaching the pressure equalization section 6, the number of porous dispersion plates 5 in the pressure equalization section 6 can be further reduced compared to the conventional one. Because you can
The configuration is simple, sufficient stirring is achieved, and the pressure is uniform, making it possible to provide a mixed gas that is optimal for combustion conditions.

As described above, this invention does not require a spiral snail-shaped case compared to the conventional one using a so-called Sirotskov fan, so the structure of the all-primary premixing gas burner can be simplified. It is possible to reduce the size of the air and fuel gas mixture and to uniformly send the mixture of air and fuel gas to the entire combustion flame face plate in a sufficiently stirred state.
In addition, it is possible to eliminate the outflow of fuel gas and the like to the outside, and to achieve practical beneficial effects such as being able to reduce costs.

[Brief explanation of the drawing]

The drawings show an embodiment of this invention; Fig. 1 is a front sectional view of the main part, Fig. 2 is a side sectional view of the main part, Fig. 3 is a front sectional view of the main part of another embodiment, and Fig. 4 is a front sectional view of the main part. is a front view of a conventional centrifugal blower, and FIG. 5 is a side sectional view of the same. 1...Gas burner, 2...Centrifugal blower, 3...
...Air intake part, 4...Gas supply nozzle, 5...Porous distribution plate, 6...Pressure equalization part, 7...Combustion flame face plate, 8...Burner case, 9...Narrowed part, 1
0... Fan, 11... Motor, 12... Rotating shaft, 13... Inclined inner wall, 21... Diffusion fixture, 2
2... Connecting flange, 23... Narrowed portion, 24
...Packing, 31...Centrifugal blower, 32...
Fan case, 33... Fan cover, 34...
Motor, 35... Juan.

Claims (1)

[Scope of utility model registration request] A centrifugal blower, a gas supply nozzle disposed in the air intake part of the centrifugal blower, a pressure equalization part that further stirs, disperses and equalizes the pressure of the mixed gas of air and fuel gas sent out from the blowing outlet of the centrifugal blower, and a pressure equalization part. In an all-primary premixed gas burner for a domestic water heater, which consists of a combustion flame face plate that burns mixed gas from The burner case, which is arranged at right angles and covers the entire gas burner, is formed almost integrally, and the burner case around the fan of the centrifugal blower is arranged in a roughly lattice shape that expands toward the combustion flame face plate. The gas supply nozzle is arranged to blow out the fuel gas into the air flow from the air intake, and the fan of the centrifugal blower is arranged within the inlet opening for the mixture of air and fuel gas in the burner case. An all-primary premixed gas burner for a domestic water heater, characterized in that a negative pressure section is located.