JPH041247B2 - - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Field of Industrial Application) This invention relates to a Bunsen gas burner,
The Bunsen method is adopted, in which a part of the air required for combustion is forcibly taken in as primary air when fuel gas is supplied by a blower, and secondary air is sent out from near the flame opening for combustion. The supply ratio is linked with valve control to maintain an appropriate ratio and ensure stable combustion against pressure changes caused by external factors such as gusts of wind. The present invention relates to a Bunsen type gas burner which allows a large down ratio (referred to as down ratio), and proportionally controls secondary air to shorten the flame and reduce combustion noise.

(Prior art) Conventional Bunsen gas burners are of a type in which primary air is sucked in under negative pressure by feeding fuel gas, and secondary air is naturally taken in from the atmosphere.
Two systems have been proposed, one in which the primary air and the secondary air are forcibly taken in by a blower, in particular a centrifugal blower.

Recently, gas burners of the latter type have been attracting attention as they can be miniaturized.

To adjust the primary air amount and fuel gas amount in this type of gas burner, a two-system control method is adopted in which the primary air amount and fuel gas amount are controlled separately. The amount of primary air can be controlled by appropriately changing the rotational speed of the centrifugal blower or by throttling the air intake port of the centrifugal blower, and the amount of fuel gas can be controlled by controlling the gas delivery valve. This is done by opening and closing as appropriate.

Recently, many systems have been equipped with electronic control circuits for automatic control, and are operated to maintain an appropriate ratio of primary air and fuel gas at all times.

On the other hand, in the case of secondary air, the air delivery path from the centrifugal blower is branched to form one path for primary air and the other for secondary air. It is sent out as secondary air.

Further, a gas burner has been proposed in Japanese Utility Model Application Publication No. 58-37018, which has a structure in which the amount of secondary air is adjusted while keeping the ratio of the mixed gas of primary air and fuel gas constant.

Furthermore, in Japanese Patent Application Laid-Open No. 58-110914, a plurality of structures for supplying secondary air are provided on both sides of the flame hole to ensure a sufficient supply of secondary air and shorten the flame. A high-load combustor that achieves this has been proposed.

(Problems to be Solved by the Invention) <Problems with the Prior Art> However, in the case of the gas burner, during maximum combustion, that is, during high-load combustion, the rotation of the centrifugal blower is increased to increase the amount of air. When the amount of gas supplied is increased accordingly, or when the amount of mixed gas supplied is decreased, that is, when low-load combustion is desired, the rotation of the centrifugal blower is slowed down, or vice versa. The amount of air was reduced by throttling the air intake of the centrifugal blower, and the amount of gas supplied was reduced accordingly.

Therefore, there is no problem during high-load combustion, but
During low-load combustion, the rotation of the centrifugal blower is slowed down or the air intake port of the centrifugal blower is throttled, so the gas delivery pressure at the centrifugal blower is low.

Then, if there is a pressure change due to an external factor, such as a gust of wind blowing into the exhaust port, if the gas delivery pressure at the centrifugal blower is low, the gust of wind will blow the combustion air. As a result, the fire may be extinguished, CO may be generated, or the flame back phenomenon may occur, and reliable combustion cannot be ensured due to the influence of external wind.

Therefore, in order to prevent the fire from going out, it is necessary to ensure at least enough pressure on the side of the blast to counteract the gust of wind, and to always apply that pressure to the mixed gas of primary air and fuel gas. Must not be. In this case, it is necessary to ensure a certain level of gas delivery pressure at the centrifugal blower, so the rotation of the centrifugal blower cannot be slowed down or the air intake port cannot be narrowed too much. Therefore, it becomes impossible to reduce the amount of mixed gas supplied too much.

As a result, there was a problem that the turndown ratio could not be increased.

Furthermore, combustion noise changes depending on the amount of secondary air when primary air and fuel gas are delivered at a predetermined ratio. In other words, combustion noise can be minimized by appropriately adjusting the ratio of primary air to secondary air to make it appropriate depending on the combustion state. However, in the aforementioned two-system control type gas burner, the ratio of primary air to secondary air can be controlled proportionally by appropriately controlling the rotation speed of the centrifugal blower or appropriately narrowing the air intake port of the centrifugal blower. It is not possible to control the proportion of primary air and secondary air to be adjusted appropriately depending on the combustion state.

Therefore, it is impossible to appropriately set the ratio of primary air and secondary air that is optimal for suppressing combustion noise. The current situation was that it was unavoidable for this to occur.

On the other hand, in the case of the two-system control system, when performing electronic control as described above, separate electronic circuits are required to control the primary air and the fuel gas.

As a result, the electronic circuit becomes complicated, and the number of parts also increases, leading to a significant increase in cost.

Furthermore, although the gas burner proposed in Jitsukusho No. 58-37018 has an interlocking structure, the secondary air is only sent out from the side of the burner part. The problem is that the secondary air does not spread, and if you try to spread it, it is necessary to arrange secondary air outlets around each individual flame port, which makes the structure complicated. In addition, since the amounts of primary air and secondary air are regulated by the same control valve, the setting of the mixing ratio of fuel gas and primary air will affect the amount of secondary air supplied, so adjustment is difficult. This method is very difficult, and the structure of the disclosed control valve is also complicated, leading to problems that increase processing costs.

On the other hand, for this gas burner, JP-A-58-110914
Even if the configuration for supplying secondary air to the high-load combustor proposed in the publication is adopted, the amounts of primary air and secondary air are regulated by the same control valve, so the amount of fuel gas and Setting the mixing ratio with primary air affects the amount of secondary air supplied, making it very difficult to adjust, and the structure of the disclosed control valve is also complex, leading to increased processing costs, which has not yet been resolved. Nakatsuta.

<Technical Problem> Therefore, in view of the above-mentioned problems, the present invention has been made to improve the mixing ratio between the primary air amount and the fuel gas amount while minimizing the number of component parts in a Bunsen gas burner. The centrifugal blower must be able to maintain a stable and appropriate ratio, adjust the amount of secondary air appropriately, and resist the increased pressure caused by external factors so as not to be affected by external wind. By constantly ensuring gas delivery pressure, we achieve reliable combustion, shorten the flame, and achieve a large turndown ratio.
It was created with the goal of minimizing combustion noise.

[Structure of the invention]

(Means for solving the problem) This invention forcibly takes in a part of the air necessary for combustion using a blower as primary air when fuel gas is supplied, and also sends out secondary air from the vicinity of the flame opening to combust. In the Bunsen type gas burner, the flame ports are formed by opening holes in a flame port face plate having an appropriate thickness as a set of appropriately spaced holes, branching the air intake path from the blower, and connecting one side to the primary air. The secondary air outlet is placed on the upper surface of the burner face plate as a flow path for the burner, or is arranged parallel to the burner outlet so as to alternate with the set of burners, and the secondary air is blown out in a fan shape on the upper surface. A primary air volume control valve that is formed to communicate with a secondary air jet pipe provided with a jet hole, uses the other branched air intake passage from the blower as a secondary air passage, and adjusts the amount of primary air. and the fuel gas amount control valve are formed to operate in conjunction with each other while maintaining the supply ratio of primary air and fuel gas at an appropriate ratio, and
A secondary air amount control valve that adjusts the amount of secondary air is also formed to be interlocked to adjust the amount of secondary air to an appropriate amount, and the tapered portion at the tip of the primary air amount control valve enters and exits the fuel gas delivery hole. A flange is formed in the middle part of a needle-shaped fuel gas regulator that adjusts the amount of fuel gas by this, and this flange is connected to a mixed gas outlet through which a mixed gas of primary air and fuel gas passes. A mixed gas amount adjustment hole formed by narrowing the inner periphery of the passage is formed so that it can approach and separate as the tapered portion enters and exits the fuel gas delivery hole, and the amount of mixed gas is adjusted by the approach and separation. The above-mentioned problems are solved by forming the fuel gas regulator so that the amount of primary air can be adjusted by adjusting the amount of primary air, and by forming the fuel gas regulator so that it can be operated from the outside.

(Function) The Bunsen gas burner according to the present invention has the following features:
In Bunsen gas burners, a part of the air required for combustion is forcibly taken in as primary air when fuel gas is supplied by a blower, and secondary air is sent out from near the flame opening for combustion.The blower is rotated at a constant speed. air from the blower to the air intake passage while maintaining a constant pressure.

This air intake path is branched, and primary air is introduced from one of the branched air intake paths toward the flame outlet, and secondary air is introduced from the other air intake path toward the flame outlet.

At that time, the primary air amount control valve that adjusts the amount of primary air provided in the primary air feed path and the fuel gas amount adjustment body are operated while maintaining the supply ratio of primary air and fuel gas at an appropriate ratio. By interlocking, a mixed gas of air and fuel gas in an appropriate ratio is ejected from the flame port placed on the downstream side. At the same time,
The secondary air is also regulated to an appropriate amount by interlocking with the secondary air flow control valve installed in the secondary air feed path, and is ejected from the vicinity of the flame port, ensuring stable combustion and minimizing combustion noise. Find the appropriate amount of secondary air to be used and feed the secondary air at that ratio.

The amount of primary air can be adjusted by forming a flange in the middle of a needle-shaped fuel gas regulator whose tapered end moves in and out of the fuel gas delivery hole to adjust the amount of fuel gas. ,
The mixed gas amount adjustment hole is formed by narrowing the inner periphery of the passage to the mixed gas outlet through which the mixed gas of primary air and fuel gas passes.
As the tapered portion moves in and out of the fuel gas delivery hole, it is moved toward and away from the fuel gas delivery hole, and the amount of mixed gas is adjusted by the approach and separation, thereby adjusting the amount of primary air.

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

That is, the reference numeral 1 shown in the figure is a Bunsen type gas burner 1 used in a domestic water heater,
A centrifugal blower 2, a mixing section 4 disposed across the blower outlet 3 of the blower 2, which mixes primary air, which is a part of the air sent out from the centrifugal blower 2, and fuel gas; A gas combustion flame port 5 arranged on the downstream side and a secondary air supply unit that sends air other than primary air from the centrifugal blower 2 to the gas combustion flame port 5 as secondary air. 17.

As shown in FIG. 1, the centrifugal blower 2 includes a fan 8 consisting of a large number of curved blades that rotate around a drive shaft 7 by the drive rotational force of a motor 6, and a structure surrounding the fan 8. A so-called Sirotskov fan is made up of a snail-shaped casing 9, an air intake port 10 opened on the side of the fan 8 of the casing 9, and an air outlet 3 formed in the tangential direction forward of the fan 8 in the casing 9. I am using it.

The flame port 5 for gas combustion has a flame port 11 formed of a small hole.
A burner port face plate 12 having an appropriate thickness with a set of holes drilled at appropriate intervals, and a flame outlet face plate 12 that is placed on the upper surface of the burner face plate 12 between the set of burner ports 11 on this burner face face plate 12, or placed parallel to the vicinity. The secondary air ejection pipes 13 are arranged so as to be arranged alternately with a set of secondary air ejection pipes 13, and the secondary air ejection pipes 13 are, for example, elongated rectangular sections with one short side rounded. The rounded part is the top surface, and slit-shaped secondary air jet holes 1 are provided on the top surface at appropriate intervals in a direction perpendicular to the axis of the secondary air jet pipe 13.
4 is opened to blow out secondary air in a fan shape.

Then, the air intake passage 15 connected to the air outlet 3 of the centrifugal blower 2 is branched, and one side is a primary air passage 16 and the other side is a secondary air passage 17, as shown in FIGS. 2 to 4. , a primary air passage 16 is disposed in the center, and the secondary air passages 17 are appropriately divided on both sides thereof.

The mixing section 4 is arranged in this primary air passage 16 .

The mixing section 4 is formed so that one opening of a substantially cylindrical casing 21 is arranged opposite to the air outlet 3 of the centrifugal blower 2, and primary air can be introduced from the secondary air passage 15.

A substantially cylindrical mixed gas amount regulator 22 that is slidable in the axial direction is disposed within the casing 21 .
The mixed gas amount adjusting body 22 narrows the inner periphery of a passage in the casing 21 up to a mixed gas outlet 24 described later to form a mixed gas amount adjusting hole 23 .

On the other hand, a mixed gas outlet 24 is formed in the casing 21 to extend from an end opposite to the outlet 3 of the centrifugal blower 2 toward the gas combustion flame port 5, and the opposite end of the casing 21 is An actuating body 25 is provided for holding a fuel gas regulating body 28 (described later) in reciprocating motion in the axial direction of the casing 21.

And the centrifugal blower 2 in the casing 21
A fuel gas intake part 26 is provided near the end of the ventilation outlet 3 or at the ventilation outlet 3, and the fuel gas intake part 26 is arranged from the fuel gas intake part 26 on the central axis of the casing 21 and toward the downstream direction of the centrifugal blower 2. A cylindrical fuel gas delivery port 27 is formed.

Further, the fuel gas regulator 28 held by the operating body 25 has one end tapered and inserted into the fuel gas delivery port 27 .

On the other hand, in the fuel gas delivery port 27, a fuel gas delivery hole 29 whose inner peripheral diameter is narrowed to a small size and one tapered end of the fuel gas adjustment body 28 is inserted near the opening end thereof. , and the fuel gas is sent out from the gap between the fuel gas delivery hole 29 and the tapered portion at one end of the fuel gas adjustment body 28, and serves as a needle valve as a fuel gas amount adjustment valve. be.

As described above, the other end of the fuel gas regulator 28 is held by the actuator 25, and by pushing and pulling the actuator 25, the fuel gas regulator 28 is moved to the fuel gas delivery hole 29. For example, the operating body 25 can be used as a temperature sensing control device to automatically control the temperature sensing control device. By doing so, the gap between the fuel gas delivery hole 29 and the tapered portion at one end of the fuel gas adjustment body 28 expands or contracts, and serves as the needle valve to adjust the amount of fuel gas delivered. .

Moreover, a flange 30 is fixedly provided on the fuel gas regulator 28, and the flange 30 is located on the side of the mixed gas outlet 24 from the position of the mixed gas amount adjusting hole 23 of the mixed gas amount regulator 22. The gap between the flange 30 and the mixed gas amount adjusting hole 23 narrows as the flange 30 approaches the mixed gas amount adjusting hole 23 from the mixed gas outlet 24, so that the flow rate by the valve is reduced. It is designed to be able to be adjusted and to function as a mixed gas amount regulating valve.

By doing so, the flow rate adjustment using the mixed gas amount adjustment hole 23 and the flange 30 is as follows.
Since the fuel gas supply amount is controlled by the needle valve formed by the fuel gas regulator 28 and the fuel gas delivery hole 29, the amount of primary air is also controlled as a result. This means that it also worked. Furthermore, since the fuel gas regulator 28 and the flange 30 are integrated, the amount of primary air and the amount of fuel gas can be controlled in conjunction with each other.

Note that the flange 30 is connected to the mixed gas amount adjustment hole 2.
If the gas burner 3 is movable to a position where it is closed, for example, in a water heater using this gas burner 1, when cold water is passed through a heat exchanger (not shown) without being combusted, the internal Even if water vapor condenses on the heat exchanger or the like, the flange 30 prevents air from flowing into the centrifugal blower 2, so that condensation can be minimized.

On the other hand, an outer cylinder 31 is provided from the flange 30 toward the fuel gas delivery port 27, and this outer cylinder 31 is fitted onto the fuel gas delivery port 27 with a slight gap. In this case, the outer cylinder 31 has a flange 30
A small cylindrical body is fitted externally to the fuel gas regulating body 28 without a gap up to the vicinity of the tapered part of the fuel gas regulating body 28, and a large cylinder with an inner diameter is fitted externally to the fuel gas delivery port 27 with a step near the tapered part. Form in the body. Further, in this outer cylinder 31, for example, a suitable number of gas ejection holes 32 are bored in the circumferential direction near the step portion of the large cylinder body, and are formed so as to eject the fuel gas laterally.

Further, the mixed gas amount regulator 22 is configured to reciprocate in the axial direction of the casing 21.

The flow rate adjustment of the primary air and fuel gas by the mixing part 4 formed in this way is as follows.

That is, when primary air branched from the centrifugal blower 2 is sent toward the operating body 25 and fuel gas is supplied from the fuel gas delivery port 27 at the same time, the fuel gas flows from the gas jet hole 32 of the outer cylinder 31 into the mixed gas amount regulator 22. is ejected and mixed with the air.

At that point, move the mixed gas amount adjusting body 22 appropriately in advance to align the flange 30 and the mixed gas amount adjusting hole 23.
The amount of primary air flowing to the mixed gas outlet 24 is set by adjusting the gap between the primary air and the fuel gas so as to have an appropriate mixing ratio with the ejected fuel gas.

Thereafter, by pushing and pulling the fuel gas regulator 28, the gap between the tapered part at the tip of the fuel gas regulator 28 and the fuel gas delivery hole 29 and the gap between the mixed gas amount adjusting hole 23 and the flange of the mixed gas amount adjusting body 22 are adjusted. 30
and the gap between the two at the same time. In this way, even if the amount of mixed gas increases or decreases, it is possible to always maintain an appropriate ratio of air and fuel gas while supplying the mixture.

As a result, by only pushing and pulling the fuel gas regulator 28 as a single actuator, it is possible to increase or decrease the amount of mixed gas while keeping the ratio between the primary air amount and the fuel gas amount always at an appropriate ratio. It is easy to perform and does not require conventional complicated electronic circuits, which simplifies the structure and reduces costs.

On the other hand, as described above, the secondary air is formed to flow into two secondary air passages 17 branched on both sides of the central primary air passage 16, respectively.
This secondary air supply path 17 includes a secondary air amount control valve 4.
1 is provided.

As shown in FIG. 4, this secondary air amount control valve 41 is made of a plate material bent so that the planar shape becomes a U-shape, and the plate portions correspond to both open sides of this U-shape. A slide valve 42 is formed to appropriately adjust the cross section of the secondary air passage 17 through which the secondary air passes.

The slide valve 42 has a facing interval that is approximately the same as the spacing between the two secondary air passages 17, and is arranged so as to slide in almost contact with the side wall of the secondary air passage 17. ing.

Moreover, the middle portion of the U-shape of the secondary air amount adjusting valve 41 is connected to the outer cylinder 31.

Its connection structure is as follows.

That is, a primary air passage 43 is opened approximately in the center of the intermediate portion of the secondary air amount control valve 41, a connecting cylinder 44 is disposed at the center of the primary air passage 43, and a connecting cylinder 44 is arranged radially from the periphery of the primary air passage 43. Support piece 4 arranged
5 holds the connecting cylinder 44 within the primary air passage 43. By externally fitting and fixing this connecting cylinder 44 to the outer cylinder 31, the secondary air amount regulating valve 41
It connects to Anu.

Then, the secondary air amount adjustment valve 41 and the fuel gas adjustment body 28 are connected via the outer cylinder 31, and the secondary air amount adjustment valve 41 is linked to the fuel gas adjustment body 28.
1 to reciprocate, thereby causing the secondary air passage 17 to
The secondary air passage cross section of the fuel gas is changed so that the amount of secondary air delivered can be adjusted in conjunction with the adjustment of the primary air and fuel gas. Note that the interlocking form of the fuel gas regulator 28 and the secondary air amount regulating valve 41 is not limited to the structure described above, and may be of any type.

The secondary air sent to the secondary air passage 17 in this way enters the secondary air chamber 47 from the secondary air outlet 46 and from the secondary air chamber 47 to the secondary air outlet 5 of the gas combustion flame port 5. The secondary air enters the secondary air jetting pipe 13 and is sent out from the secondary air jetting hole 14. Then, the secondary air is ejected in a fan shape from the secondary air outlet 14, acts on the inner flame 48 formed by combustion of the mixed gas ejected from the flame port 11 of the flame port face plate 12, and acts on the outer flame 48.
9, which means complete combustion.

Also, for mixed gas of primary air and fuel gas,
The mixed gas is sent from the mixed gas outlet 24 to the gas combustion flame port 5 and ejected from the flame port 11 .

The reference numeral 50 in the figure is a mixer plate disposed between the mixed gas outlet 24 and the gas combustion flame port 5, which disperses the mixed gas appropriately while stirring and mixing it, and sends it to the gas combustion flame port 5. 51 is a distribution plate for uniformly sending secondary air to each secondary air jetting pipe 13.

Then, while the centrifugal blower 2 is kept rotating at a constant rate, the flow rates of the primary air, secondary air, and fuel gas are linked depending on the width of the gap between the fuel gas delivery hole 29 of the fuel gas regulator 28 and the flange 30. Therefore, even during minimum combustion, the gas delivery pressure in the centrifugal blower 2 is maintained at a sufficient pressure to counter the increase in outside air pressure due to gusts of wind, etc. Since it is less susceptible to the influence of external wind, etc., the turndown ratio can be increased accordingly. In other words, if you secure a certain amount of gas delivery pressure at the centrifugal blower 2, even if the gas tries to flow backwards due to wind from the outside, the backflow will be suppressed by the delivery pressure at the centrifugal blower 2. , which will no longer have a negative effect on combustion.

Furthermore, combustion noise changes depending on the amount of secondary air when primary air and fuel gas are delivered at a predetermined ratio. Therefore, by taking into account the appropriate ratio of primary air and fuel gas, the amount of secondary air is designed to minimize combustion noise and CO generation, and to increase the turndown ratio. ,
The secondary air amount control valve 41 and the fuel gas control body 28 are used to appropriately set the amount to the optimum amount to achieve a short flame.
By appropriately setting the fixed position and performing proportional control, it is possible to reliably suppress and reduce the combustion noise.

It goes without saying that the Bunsen type gas burner according to the present invention is not limited to the structure of the embodiment described above.

〔Effect of the invention〕

This invention configured as described above employs a Bunsen method in which a part of the air necessary for combustion is forcibly taken in as primary air by the blower 2 when fuel gas is supplied, and secondary air is sent out from the vicinity of the flame nozzle 11 for combustion. In the gas burner, the air intake path 15 from the blower 2 is branched, one of which is used as the primary air feeding path 16, and the other is used as the secondary air feeding path 17, and the primary air is used to adjust the amount of primary air. The amount control valve and the fuel gas amount control valve are formed to work together while maintaining the supply ratio of primary air and fuel gas at an appropriate ratio, and a secondary air amount control valve 41 that adjusts the amount of secondary air is also provided. By forming the secondary air so as to be interlocked to adjust the appropriate amount, the fuel gas amount adjustment valve or the primary air amount adjustment valve can be used to supply primary air and fuel gas at an appropriate ratio in advance. If adjusted, the primary air amount adjustment valve and the fuel gas amount adjustment valve can be linked while maintaining the supply ratio of primary air and fuel gas at an appropriate ratio, so that the primary A mixed gas of air and fuel gas can be sent and combusted at a desired flow rate.

Therefore, the supply ratio between the amount of primary air and the amount of fuel gas is always an appropriate ratio even if the amount increases or decreases, and stable combustion can be ensured. Moreover, since the conventional electronic circuits, etc., which are complex, are not required, the structure is simplified, which leads to cost reduction and miniaturization.

At that time, the secondary air can also be adjusted in conjunction with the secondary air amount control valve 41, so that the optimum amount of secondary air necessary for combustion of the mixed gas is delivered to the flame port 1.
Since it can be sent out from the vicinity of 1, a stable flame can be obtained.

Since the amount of primary air and the amount of fuel gas are each adjusted by the valve mechanism, and the secondary air is adjusted by the secondary air amount adjustment valve 41, the centrifugal blower 2 is rotated at a constant speed. In particular, a flange 30 may be attached to the intermediate portion of the needle-shaped fuel gas regulator 28 that adjusts the amount of fuel gas by the tapered portion of the tip of the primary air amount regulating valve going in and out of the fuel gas delivery hole 29. The flange 30 is formed by narrowing the inner periphery of the flange 30 to the passage up to the mixed gas outlet 24 through which the mixed gas of primary air and fuel gas passes. The hole 23 is formed so as to be able to approach and separate as the tapered portion enters and exits the fuel gas delivery hole 29, and by adjusting the amount of mixed gas by the approach and separation, the amount of primary air can be adjusted as a result. However, since the fuel gas regulator is configured to be operable from the outside, it has excellent operability, and the amount of primary air and secondary air is not regulated by the same regulating valve. This solves the problem that setting the mixing ratio of fuel gas and primary air affects the amount of secondary air supplied and is very difficult to adjust, and the structure is simple and processing costs can be reduced.

In other words, since the amount of primary air is adjusted as the amount of mixed gas, the gas delivery pressure of the centrifugal blower 2 is maintained at a relatively high pressure, so even during minimum combustion, external pressure caused by gusts of wind etc. The combustion air is no longer suppressed, and the fire is extinguished, or the generation of CO or the flame back phenomenon is eliminated. The minute turndown ratio can be increased.

The mixed gas, which is backed up and mixed at an appropriate ratio by ensuring a constant pressure with the centrifugal blower 2, is blown out at the gas combustion flame port 5 because an appropriate amount of secondary air is also blown out. It can be burned in a stable state.

Further, combustion noise can also be minimized because the amount of secondary air can be controlled proportionally, taking into consideration the appropriate ratio of primary air and fuel gas, as described above.

As explained above, according to the present invention, in a Bunsen gas burner, the number of component parts can be kept to a minimum while the mixing ratio between the primary air amount and the fuel gas amount can always be maintained at an appropriate ratio. , the secondary air can also be adjusted to the appropriate amount, and the blower's delivery pressure is set to a level that can counteract the increase in pressure caused by external factors, achieving reliable combustion and reducing turndown. It has various advantages such as being able to obtain a large ratio and minimizing combustion noise, so it can reduce the cost of water heating equipment and achieve quiet combustion, while also being able to handle all types of hot water heating in the home. It has a great effect.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a front sectional view, FIG. 2 is a sectional view along the - arrow line in FIG. 1, FIG. 3 is a side sectional view, and FIG. 4 is a primary air passage. FIG. 3 is a cutaway perspective view of main parts showing the arrangement of a secondary air feed path and a secondary air amount control valve. 1...Gas burner, 2...Centrifugal blower, 3...
...Blower outlet, 4...Mixing section, 5...Gas combustion flame port, 6...Motor, 7...Drive shaft, 8...Fan, 9...Casing, 10...Air intake port,
11...flame port, 12...flame port face plate, 13...secondary air jet pipe, 14...secondary air jet hole, 15...
Air intake path, 16... Primary air feed path, 17... Secondary air feed path, 21... Casing, 22... Mixed gas amount adjustment body, 23... Mixed gas amount adjustment hole, 24
...Mixed gas outlet, 25... Working body, 26...
Fuel gas intake part, 27...Fuel gas delivery port, 2
8...Fuel gas regulator, 29..., fuel gas delivery hole, 30...flange, 31...outer cylinder, 32...
Gas blowout hole, 41...Secondary air amount control valve, 42...
...Slide valve, 43...Primary air passage, 44...
Connection tube, 45... Support piece, 46... Secondary air outlet, 47... Secondary air chamber, 48... Inner flame, 49...
...external inflammation.

Claims (1)

[Claims] 1. In a Bunsen gas burner, in which a part of the air required for combustion is forcibly taken in as primary air when fuel gas is supplied by a blower, and secondary air is sent out from the vicinity of the flame port for combustion, the flame port is The holes are formed by opening holes in a thick burner face plate at appropriate intervals, branching the air intake path from the blower, and placing one of the holes on the upper surface of the burner face plate as a passage for the primary air. Alternatively, they are arranged parallel to each other in the vicinity, alternately with a set of flame ports, and communicated with a secondary air jetting pipe provided with a secondary air jetting hole on the top surface so that secondary air can be jetted out in a fan shape. A primary air amount control valve and a fuel gas amount control valve are formed so that the air intake path from the blower branches off and the other side is used as a secondary air delivery path to adjust the amount of primary air.
The primary air and fuel gas supply ratio is configured to operate in conjunction with each other while maintaining the supply ratio at an appropriate ratio, and the secondary air amount control valve that adjusts the amount of secondary air is also configured to operate in conjunction to adjust the amount of secondary air to an appropriate amount. The primary air amount regulating valve has a flange formed in the middle part of a needle-shaped fuel gas regulating body whose tapered end enters and exits the fuel gas delivery hole to regulate the amount of fuel gas. to the fuel gas delivery hole, which is formed by narrowing the inner periphery of the passage to the mixed gas delivery port through which the mixed gas of primary air and fuel gas passes. The fuel gas regulator is formed so as to be able to approach and separate as the tapered portion moves in and out, and by adjusting the amount of mixed gas by the approach and separation, the amount of primary air can be adjusted as a result, and the fuel gas regulator is connected from the outside. A Bunsen gas burner characterized by being operable by the following operations.