JPH0241494Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field] The present invention relates to a pilot burner.

[Prior Art] Conventionally, when configuring a pilot burner, as shown in FIGS. 7 and 8, one end side opening is a flame port 13.
A head member 2 has a combustion air supply passage 15 and a fuel gas supply passage 16 connected to the other end of a tubular body 14, and has a plurality of small-diameter air-fuel mixture jet holes 21a.
1 was housed in the tubular body 14 in a position that crossed the internal flow path of the tubular body 14 near the burner port 13 so as to enhance the flame holding effect (references cannot be provided).

[Problems to be solved by the invention] However, although the stability of combustion can be improved to some extent by the flame-holding effect of the head member, the fuel gas supply path connecting the fuel gas and combustion air to the tubular body and the combustion Since the fuel gas and combustion air are mixed by simply supplying the air from the air supply path into the inside of the tubular body, the miscibility of the fuel gas and combustion air is low, and for this reason, there is still insufficient fuel gas and combustion air. There was a problem that combustion stability could not be achieved.

By the way, in the case of main burners, various methods have been developed to improve the mixing properties of fuel gas and combustion air as well as the flame holding effect and combustion stability, but compared to main burners, Because of its small diameter structure, it is difficult to apply the various measures used in the main burner to the pilot burner, which inherently needs to be configured with a fairly small diameter. It's becoming a hindrance.

An object of the present invention is to improve the combustion stability of a pilot burner through a rational and simple improvement commensurate with the small diameter configuration of the pilot burner.

[Means for solving the problem] The characteristic configuration of the pilot burner according to the present invention is as follows:
A combustion air supply path is connected to the other end of the tubular body with one end opening as a flame port, and a fuel gas jet pipe connected to the fuel gas supply path is connected to the inside of the tubular body. The ejecting port of the fuel gas ejecting pipe is located near the inner circumferential surface of the tubular body, and the ejected fuel gas is directed toward the flame port in a spiral flow along the inner circumferential surface of the tubular body. The reason is that it is arranged in the direction in which it was supplied, and its functions and effects are as follows.

[Effect] In other words, when the fuel gas is ejected from the fuel gas ejection pipe in such a way that it is supplied toward the flame port with a spiral flow along the inner circumferential surface of the tubular body, the flame holding effect is achieved due to the spiral flow action. Combustion air that has been raised and supplied to the inside of the tubular body and the jetted fuel gas are sufficiently mixed as a result of the spiral flow.

In addition, by arranging the ejection port of the fuel gas ejection pipe near the inner circumferential surface of the tubular body, the spiral flow of fuel gas along the inner circumferential surface of the tubular body is caused to flow along the inner circumferential surface of the tubular body as the fuel gas is ejected. Effectively occurs in a guided state,
Thereby, the above-mentioned flame stabilization effect and improvement in mixability due to the spiral flow effect can be effectively achieved.

On the other hand, in terms of structure, the improvement consists in simply arranging the ejection port side portion of the fuel gas ejection pipe inside the tubular body so that the ejection port of the fuel gas ejection pipe is located near the inner circumferential surface of the tubular body in a predetermined direction. Therefore, improvements can be easily made even to small-diameter tubular bodies.

[Effect of the invention] As a result of the above, the flame holding effect of the combustion flame and the mixability of the fuel gas and the combustion air are both high, so it is possible to create a pilot burner with extremely excellent combustion stability, and as a result, The reliability of the pilot burner's original functions, such as the ignition function for the main burner and the flame holding function for the main burner, has been greatly improved.

In addition, since the structure is simple and improved to match the pilot burner, which inherently needs to be constructed with a small diameter, it is advantageous in terms of manufacturing and manufacturing costs.

Furthermore, in conventional pilot burners in which the head member is installed inside the tubular body in such a manner that it crosses the internal flow path, the ignition spark rod, combustion flame detector, etc. must be exposed to the flame opening from outside the tubular body. However, in the case of the pilot burner according to the present invention, there is only a fuel gas jet pipe inside the tubular body, so the ignition spark rod, combustion flame detector, etc. can be connected to the flame opening through the inside of the tubular body. This also allows for the pilot burner to be placed directly in front of the pilot burner if necessary, which also has the advantage of making the overall configuration of the pilot burner more compact.

[Example] Next, an example of the present invention will be described based on the drawings.

Fig. 4 shows a high-speed burner used for various purposes.A cylindrical burner casing 2 with a main flame port 1 formed at its tip is fitted with a conical combustion tube 3 whose large-diameter opening is the main flame port. A gas nozzle 5 is installed so as to face the main flame port 1 in the direction of the cylinder axis of the combustion tube 3, and the gas nozzle 5 is installed so that the fuel gas from the fuel gas supply path 4 is directed toward the main flame port 1 in the direction of the cylinder axis of the combustion tube 3. It is provided so as to be connected to the opening.

A large number of air holes 8 are provided for blowing the combustion air supplied from the combustion air supply path 7 into the burner casing 2 from the outer periphery of the combustion tube 3 into the inside.
The fuel gas ejected from the gas nozzle 5 and the combustion air blown from the multiple air holes 8 are mixed and combusted inside the combustion tube 3, and the combustion occurs. The flame is ejected from the main flame port 1 at high speed.

9 in the figure is an annular member attached to the inner circumferential surface of the combustion tube 3 for flame stabilization. Lift of the combustion flame is suppressed by creating a negative pressure region near the side of the main flame port 1.

Further, reference numeral 10 denotes a baffle plate for evenly distributing combustion air around the outer circumference of the combustion tube 3.

Large diameter side opening of combustion tube 3 and burner casing 2
A cooling device is provided between the combustion tube 3 and the combustion tube 3 so that a part of the combustion air supplied to the outer periphery of the combustion tube 3 is jetted toward the main flame port 1 side as cooling air along the inner peripheral surface of the burner casing 2. The cooling effect of the annular air passage 11 suppresses overheating of the large-diameter opening of the combustion cylinder and the main flame opening of the burner casing.
This is designed to prevent burnout due to overheating. Note that the cooling air ejected from the cooling annular air passage 11 has a cooling effect and is finally consumed as combustion air.

In this high-speed burner, pilot burner 1
2 is integrally installed in the gas nozzle 5, and as a main body component of the pilot burner 12, a tubular body 14 having one end opening as a flame port 13 for the pilot flame is arranged concentrically with the gas nozzle 5. Further, the flame port 13 is installed inside the gas nozzle 5 such that it faces the main flame port 1 and is located at the fuel gas ejection port of the gas nozzle 5.

In other words, the pilot burner 12 is connected to the gas nozzle 5.
By installing the pilot burner 12 inside the combustion tube 3, the pilot burner 12 can be prevented from causing a drift in the flow of the main flame air-fuel mixture inside the combustion tube 3, thereby making it possible to form a good main flame without any deviation. It's like this.

Further, by integrally incorporating the pilot burner 12 into the gas nozzle 5, the overall structure of the high-speed burner is simplified and the ignitability of the high-speed burner is improved.

Regarding the specific structure of the pilot burner 12,
As shown in FIGS. 1 to 3, the above-mentioned tubular body 1 has an opening at one end as a flame port 13 for a pilot flame.
A combustion air supply path 15 for a pilot flame that supplies combustion air into the inside of the tubular body is connected to the other end side of the fuel gas supply path 1 for the pilot flame.
6, the fuel gas ejection pipe 17 connected to the tubular body 14
The flame outlet 13 is extended inside the flame outlet 13 .

Then, the ejection port 17a of the fuel gas ejection pipe 17
is arranged near the inner circumferential surface of the tubular body 14 in such a direction that the fuel gas ejected therefrom is supplied toward the flame port 13 in a spiral flow along the inner circumferential surface of the tubular body 14. Along with the ejection, a spiral flow is effectively generated using the inner circumferential surface of the tubular body 14 as a guide.

In other words, the spiral flow that accompanies the jetting of the fuel gas produces a high flame-holding effect on the pilot flame, and also improves the mixing properties of the combustion air supplied inside the tubular body and the jetted fuel gas, thereby increasing the flame stability of the pilot flame. , the combustion stability of the pilot burner 12 is improved.

In order to arrange the ejection port 17a of the fuel gas ejection pipe 17 near the inner circumferential surface of the tubular body 14 so that the above-mentioned spiral flow occurs, the ejection port side portion 17A of the fuel gas ejection pipe 17 is formed into a substantially L-shape. In the L-shaped shape, the angle α formed by the distal straight tube portion corresponding to the side of the jet nozzle and the proximal side tube portion corresponding to the other side is approximately 95° to 120°. do.

In the fuel gas ejection pipe 17, the proximal pipe portion in the L-shape and the proximal extension portion 17B connected thereto are connected to the pipe axis P of the tubular body 14.
The L
The straight pipe portion on the distal end side of the letter-shaped shape is arranged in a direction away from the radial direction of the tubular body 14 when viewed in the direction of the tube axis P of the tubular body 14, and the fuel gas ejection pipe 1
The tip end cut forming the ejection port 17a of the fuel gas ejection pipe 17 is formed in a direction substantially perpendicular to the tube axis of the fuel gas ejection pipe 17, and one side of the circumference of the tip cut is formed in the tubular body 14.
It is in contact with the inner peripheral surface of.

That is, by causing the jetted fuel gas to collide with the inner circumferential surface of the tubular body 14 in a direction different from the radial direction of the tubular body 14 immediately after being ejected from the jet port 17a, the inner circumferential surface of the tubular body 14 is caused to act as a guide. A spiral flow component force is applied to the ejected fuel gas in a direction along the inner circumferential surface of the tubular body.

In addition, the fuel gas ejection pipe 17, in which the cut end is simply orthogonal to the pipe axis and the ejection port side portion 17A is simply bent into an L-shape, is simply installed inside the tubular body 14 while appropriately arranging it. By having an extremely simple structure, the pilot burner 12 can be manufactured easily.

In the figure, 18 is an ignition spark rod, and 19 is an optical flame detector, but the structure of the pilot burner 12 is such that there is no member inside the tubular body 14 that crosses it, as described above. Utilizing this, the ignition spark rod 18 and the optical flame detector 19 are made to face the flame port 13 through the inside of the tubular body 14.
The overall structure of the pilot burner has been made more compact.

[Another example] Next, another embodiment of the present invention will be described.

The inner periphery of the tubular body 14 is oriented so that the jet nozzle 17a of the fuel gas jet pipe 17 is supplied to the flame port 13 in a spiral flow along the inner periphery of the tubular body 14. As shown in FIGS. 5 and 6, the proximal tube portion 17B of the fuel gas ejection tube 17 is extended close to the inner circumferential surface of the tubular body 14, and The ejection port side portion 17A of the fuel gas ejection pipe 17 may be bent into a spiral shape along the inner peripheral surface of the tubular body 14, and the specific shape and structure of the fuel gas ejection pipe 17 can be improved in various ways. be.

The pilot burner according to the present invention can be installed in main burners of various uses and types. Further, the specific structure attached to the main burner can be modified in various ways.

[Brief explanation of the drawing]

1 to 4 show embodiments of the present invention,
Figure 1 is a vertical cross-sectional view, Figure 2 is a - in Figure 1.
FIG. 3 is a cross-sectional view taken along the - line in FIG. 1, and FIG. 4 is a vertical cross-sectional view of the high-speed burner. FIGS. 5 and 6 are a longitudinal sectional view and a transverse sectional view showing another embodiment of the present invention. 7 and 8 are a longitudinal sectional view and a transverse sectional view showing a conventional example. 13... Flame port, 14... Tubular body, 15... Combustion air supply path, 16... Fuel gas supply path, 17...
...Fuel gas ejection pipe, 17A...Ejection port side part, 1
7a... spout.

Claims (1)

[Scope of Claim for Utility Model Registration] A combustion air supply passage 15 is connected to the other end of a tubular body 14 whose opening at one end is a flame port 13, and a fuel gas jet pipe 17 connected to a fuel gas supply passage 16.
, its spout side portion 17A is connected to the tubular body 1.
4, the ejection port 17a of the fuel gas ejection pipe 17 is located near the inner circumferential surface of the tubular body 14, and the ejected fuel gas spirals along the inner circumferential surface of the tubular body 14. The flame outlet 1 with flow
The pilot burner is arranged in such a way that it is fed towards the 3rd direction. The spout side portion 17 of the fuel gas jet pipe 17
In A, the tip end cut is made almost perpendicular to the tube axis, and the tube shape is formed into an almost L-shape bent near the spout 17a, and the bend L
The proximal end side of the letter-shaped shape is the tube axis P of the tubular body 14.
A pilot burner according to claim 1, wherein the pilot burner is arranged eccentrically and substantially parallel to the pilot burner.