JP3156731B2 - Quartz glass burner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a quartz glass processing burner used for processing large pipes and the like.
The present invention relates to a quartz glass burner combining an internal mixing type and an external mixing type.

[0002]

2. Description of the Related Art Conventionally, metal burners have been mainly used in the forming, heat-treating and melting steps of quartz glass.

However, when a metal burner is used, a high-temperature gas flame ejected from the tip of the burner and metal vapor and metal oxide released from the metal adhere to the surface of the quartz glass to be processed, and the quartz is burned. This is a factor that lowers the purity of glass, and is a problem in semiconductor manufacturing that requires high-purity quartz glass.

For this reason, a method of processing using a quartz glass burner has recently been developed.
0, JP-A-64-14510, JP-A-64-14
-28239, JP-A-64-67519,
JP-A-63-49139, JP-A-63-4914.
No. 0 and Japanese Utility Model Application Laid-Open No. 63-49143 disclose a quartz glass burner.

The quartz glass burners disclosed in these publications are broadly classified into an external mixing type and an internal mixing type, and also have a concentric tube structure, a multi-branch tube structure, or a multi-branch tube central double tube structure. The formula is shown.

[0006] Among them, the external mixing type concentric pipe structure type comprises a plurality of pipes having different cross-sectional diameters arranged concentrically, and a flammable gas and a combustion supporting gas are introduced into the pipes, respectively. External mixing is performed while the two gases are jetted from the side outlet.

Further, the external mixing type multi-branch pipe structure type has an outer cylinder having a blow-out port whose diameter is enlarged and which allows a combustible gas to pass therethrough, and a pipe line which passes a combustible gas inserted in the outer cylinder. Has,
The structure has a structure in which the combustible gas pipe is bulged along the blow-side enlarged diameter portion of the outer cylinder, and a number of branch pipes extend from the end side of the bulged portion toward the blow-out port side.

[0008] The external mixing type multi-branch pipe center double structure type is as follows:
A double pipe through which a combustible gas and a combustible gas are led out is inserted at the center of the outlet.

Further, in the internal mixing concentric tube structural type, a combustion gas flowing through the two quartz glass pipes is mixed with an aspirator at a tip end of a second quartz glass pipe inserted into the first quartz glass pipe. An internal mixing means for injecting is provided.

In the internal mixing multi-branch pipe structure type, a mixed gas pipe is provided along an outlet shaft, and a large number of branch pipes are provided at the swelling portion of the combustion-supporting gas pipe from the end side at the outlet side. And a communication portion that communicates the flammable gas passage with the air outlet on the outer peripheral side and the inner peripheral side of the bulging portion.

[0011]

However, in the concentric tube type of the external mixing type, as the diameter of the outlet increases, the mixing of oxygen gas ejected from the inner tube and hydrogen gas ejected from the outer tube increases. There is a disadvantage that it becomes insufficient and a strong heat cannot be obtained.

In addition, it is difficult to obtain a flame flow having an even flame distribution with the externally-mixed multi-branch pipe structural type. Has only an auxiliary role to correct
Because of the external mixing method, there is a drawback that it is difficult to obtain a strong flame flow that can cut a large quartz glass member as a workpiece.

Furthermore, the internal mixing concentric tube structure type is good for processing small articles or narrow areas, but large articles have a weak flame and do not have sufficient heating power during processing. The multi-branch pipe structure also has a multi-branch pipe structure to form a large-diameter combustion gas injection port, so the burner itself becomes complicated and large, and as the number of branch pipes increases, the inner pipe increases. It is difficult to adjust the amount of gas ejected from a large number of branch pipes located on the front side only by adjusting the source pressure of the pipe, and the burner is formed by thermal processing means such as welding the branch pipe to the gas pipeline. In this case, there are disadvantages that the number of processing steps is increased and that accuracy and reproducibility are problematic.

As described above, each quartz glass burner has a concentric circular structure in which pipes are combined in shape, or a structure in which a thin tube through which a combustion supporting gas is passed is welded into the pipe.
Each of the burners had a weak flame, and the burners themselves were large, resulting in poor workability.

An object of the present invention is to provide a quartz glass burner which eliminates these drawbacks, stably obtains a large heating power while being small, and further contains no impurities.

[0016]

Accordingly, the present inventor has conducted intensive studies in order to solve the above-mentioned object, and as a result, a method of mixing combustion gas in a burner (internal mixing type) and a method of discharging gas from a burner are described. If a structure combining the later mixing method (external mixing type) is provided, and a gas chamber is provided, and the ejection port is formed as a slit method, the burner itself becomes stable, evenly distributed without increasing the size and complexity of the burner itself. The inventors have found that a quartz glass burner capable of obtaining a large-diameter thermal power can be provided, and completed the present invention.

That is, according to the present invention, an internal mixed gas in which a combustible gas introduction pipe and a flammable gas introduction pipe are connected to an internal mixing chamber and mixed by a mixing means, and further a flammable gas chamber having a gas chamber provided near a jet port. This is a quartz glass burner obtained by adjusting and mixing a reactive gas introducing pipe and a flammable gas introducing pipe with a slit provided at an ejection port.

The quartz glass burner of the present invention comprises an internal mixed gas obtained by mixing a flammable gas and a flammable gas in the burner, and a separately provided flammable gas and a flammable gas. Mixing is performed.

Further, the gas ejection portion of the burner is provided with the mixed gas ejection nozzle at the center portion, and sequentially forms a combustible gas ejection slit and a combustible gas ejection disk as concentric circles extending outward from the center portion. It is configured as a plurality of slits provided, a combustible gas ejection slit.

Hereinafter, the present invention will be described more specifically with reference to the drawings. FIG. 1 is a cutaway sectional view showing one embodiment of a quartz glass burner of the present invention, and FIGS.
5 and 6 are sectional views of respective positions shown in FIG.
8 shows a flow path near the jetting portion of the combustible gas for external mixing, and FIG. 8 shows a flow channel near the jetting portion of the combustible gas for external mixing.

The burner made of quartz glass of the present invention comprises a combustible gas introduction pipe 2 and a combustible gas introduction pipe 1 for internal mixing, and a combustible gas introduction pipe 3 and a combustible gas introduction pipe for external mixing. 4, the respective gases are mixed in the internal mixing chamber 10 and reach the jet port 14 through the mixed gas pipe 25, and the flammable gas introduction pipe 4 for the external mixing is (17,18,19,2)
1) Further, the combustion supporting gas introducing pipe 3 for external mixing is branched into two (15, 16), and these are formed concentrically around the mixed gas pipe to form an injection port.

The mixed gas pipe 25 is located at the center of the burner, and has a tapered shape narrowing toward the jet port through the internal mixing chamber 10, thereby preventing flashback due to a difference in flow velocity. be able to. Further, the flammable gas introduction pipe 1 is connected to the internal mixing chamber 10, and the flammable gas flows therein. The supporting gas passage (2, 2 ′) extended from the supporting gas introducing pipe 2 and narrowed in three stages to increase the flow velocity.
2 '') causes the combustion supporting gas nozzle 9 to eject the combustion supporting gas into the internal mixing chamber 10 and is mixed with the combustible gas flowing into the internal mixing chamber.

Next, the flammable gas introduced from the flammable gas introduction pipe 4 as the external mixing gas is supplied to the internal mixing chamber 1.
0 is connected to a ring-shaped gas branch pipe 7 which is located perpendicular to the internal mixing chamber 10 and is branched into four concentric circles of the mixed gas pipe 25 from the branch pipe (17, 18, 1).
9, 21). Next, the respective branch lines 17, 18, 1
The inner cylinder 23 passes through the gas chamber 8 at the tip of
And a slit 12 provided on a concentric circle immediately above the mixed gas ejection nozzle (see FIG. 7).

Further, the slits 11 and 12 are provided with an inclination of several degrees in the coaxial direction of the burner center line, and the angle is adjusted so that the ejected gas is gathered at the center.

As described above, the gas flow is stabilized by branching the flammable gas introduction pipe into four by the ring-shaped gas branch pipe 7, and the flammable gas for external mixing is formed in a concentric circle of the mixed gas ejection nozzle 14. By jetting at two locations near the center and near the outer circumference, even when mixed with other gases, the gas balance is improved, leading to a stable supply of combustible gas, and a stable thermal power can be obtained as a whole. .

The supporting gas introduced from the supporting gas introducing pipe 3 for external mixing is branched into two by the gas branch pipe 5 in front of the ring-shaped combustible gas branch pipe 7 for external mixing (1).
5, 16), with the mixed gas line 25 as the center, it is positioned as a combustible gas line on the same concentric circle as the 4-branch tube of the combustible gas. Then, similarly to the combustible gas pipe, a gas chamber is provided at the tip and a perforated plate provided at the tip, that is, a circular slit 13 having a plurality of conducting holes in a disk body.
Squirted by. At this time, the combustion supporting gas slit 13
Is provided with an inclination of several degrees in the coaxial direction of the burner center line, and the angle is adjusted so that the ejected gas is collected at the center (see FIG. 8). Further, the slit 13 can be manufactured so as to be detachably attached to the tip of the burner.

As described above, the external mixing combustible gas injection port is not constituted by a multi-branched pipe structure such as a thin tube or the like, but is constituted by a plurality of circular slits provided in a disk body, whereby the perforated plate slit portion can be precisely formed. Machining can be performed with high accuracy and the burner manufacturing operation can be made more efficient.

Further, since a chamber is provided at the tip of the flammable gas pipe for external mixing and the flammable gas pipe, the amount of gas ejected can be made uniform with strong heating power.

The mixed gas line 25, the flammable gas lines 17, 18, 19, 21 and the combustible gas lines 15, 16
Are housed in the outer cylinder 24 at the tip end, and adjust the focusing and mixing of the gas by adjusting the respective slit angles. Further, the gas ejection portion of the burner includes the mixed gas ejection nozzle 14 at the center, a concentric circle extending outward from the center, and a combustible gas ejection slit 12, a combustible gas ejection slit 13, a combustible gas ejection. The slit 11 is used to make the flammable gas concentration at the center of the burner uniform, and further to make the mixing as a whole uniform and to obtain a stable strong heating power.

[0030]

According to the present invention, the external mixing type and the internal mixing type are combined, and a gas reservoir chamber is provided for each of the flammable gas and the supporting gas for external mixing, so that a small-sized high-power Thus, the amount of the ejected gas can be made uniform.

Further, the gas lines for the flammable gas and the supporting gas for the external mixing and the internal mixing are configured as separate lines, respectively.
The flammable gas for external mixing is divided into four branches, the flammable gas for external mixing is divided into two branches, and the flammable gas for external mixing is provided at two places near the center and the outer periphery of the concentric circle of the mixed gas ejection nozzle. The gas balance is improved, and a strong firepower corresponding to a large workpiece can be obtained with a stable and uniform flame distribution.

Further, a gas mixing chamber for internal mixing is provided,
By forming the internal mixing combustible gas pipe with a tapered structure between the outlet and the three-stage diameter of the internal combustion supporting gas pipe, internal mixing is uniform and flashback due to a difference in flow velocity can be prevented.

In addition, since the external mixing combustible gas injection port is formed in a plurality of circular slits provided in the disk,
The slit can be machined with high precision, and the burner manufacturing operation can be made more efficient. Further, by adopting a structure in which each slit is appropriately inclined, adjustment is easy, and uniform mixing and efficiency can be achieved.

With the configuration of the present invention, the burner itself can be reduced in size, high in firepower, light in weight, and work efficiency can be improved, and a stable quartz glass product with less impurities can be manufactured.

[Brief description of the drawings]

FIG. 1 is a cutaway sectional view showing one embodiment of a quartz glass burner of the present invention.

FIG. 2 is a sectional view taken along line D-D 'of FIG.

FIG. 3 is a sectional view taken along the line C-C ′ in FIG. 1;

FIG. 4 is a sectional view taken along the line B-B 'of FIG.

FIG. 5 is a sectional view taken along line E-E ′ of FIG. 1;

FIG. 6 is a sectional view taken along line A-A ′ of FIG. 1;

FIG. 7 is a flow path near a flammable gas jetting portion for external mixing.

FIG. 8 is a flow path in the vicinity of a spouting portion of the external mixing combustible gas.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 flammable gas introduction pipe for internal mixing 2 flammable gas introduction pipe for internal mixing 3 flammable gas introduction pipe for external mixing 4 flammable gas introduction pipe for external mixing 5 flammable gas branch pipe 6 flammable gas Chamber 7 Combustible gas branch pipe 8 Combustible gas chamber 9 Combustible gas nozzle 10 Internal mixing chamber 11 Combustible gas ejection slit 12 Combustible gas ejection slit 13 Combustible gas ejection slit 14 Mixed gas ejection nozzle 15 16 Flammable gas passage 17 18 19 21 flammable gas passage 22 reinforcing material 23 inner cylinder 24 outer cylinder 25 mixed gas pipeline 26 flammable gas slit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F23D 14/48-14/58 C03B 20/00 C03C 3/06

Claims (6)

(57) [Claims] 1. An internal mixed gas in which a combustible gas introduction pipe and a flammable gas introduction pipe are connected to an internal mixing chamber and mixed by a mixing means, a combustible gas introduction pipe provided with a gas chamber near an ejection port, and A quartz glass burner made by mixing and mixing a flammable gas introduction pipe with a slit provided at the ejection port. 2. An internal mixed gas in which a combustible gas introducing pipe and a flammable gas introducing pipe are connected to an internal mixing chamber and mixed by mixing means, and a combustible gas pipe extending from the combustible gas introducing pipe. Is branched into four, and the supporting gas line extending from the supporting gas introducing pipe is branched into two, and a chamber is provided in each of the branched gas lines, and the chamber is provided concentrically around the mixed gas line. A quartz glass burner having a slit outlet and mixing three types of gases. 3. An internal mixing flammable gas introduction pipe leading to an internal mixing chamber is reduced in diameter in three stages, and a flammable gas is ejected from a nozzle at the leading end of the introduction pipe and flows into the internal mixing chamber. 3. The quartz glass burner according to claim 1, further comprising a tapered mixed gas pipe which is connected to an internal mixing chamber and narrows toward a jet port. 4. The spout of the combustible gas for external mixing is a slit provided near the center and the outer periphery of a concentric circle centered on the spout of the mixed gas. The quartz glass burner according to claim 1 or 2, comprising a slit having a plurality of conduction holes in a disk body. 5. A gas ejection portion of a burner includes a combustible gas ejection slit, a combustible gas ejection circular slit, a combustible gas ejection circular slit, and a concentric circle extending outward from the center portion. 3. The burner made of quartz glass according to claim 1, wherein the burner is formed as a jet slit. 6. The respective gases are introduced from a flammable gas introduction pipe and a flammable gas introduction pipe for internal mixing, and a flammable gas introduction pipe and a flammable gas introduction pipe for external mixing. The internal mixing flammable gas introduction pipe leading to the chamber is reduced in diameter in three stages, and the nozzle at the tip of the internal mixing flammable gas introduction pipe ejects the combustion supporting gas and flows into the internal mixing chamber. The mixed gas is mixed with the flammable gas, and the mixed gas is injected through a tapered mixed gas pipe that is connected to the internal mixing chamber and narrows toward the ejection port. The gas pipeline has four branches, and the combustion-supporting gas pipeline extending from the combustion-supporting gas introduction pipe has two branches. Each of the branched gas pipelines is provided with a chamber. The gas outlet is in a concentric circle centered on the mixed gas outlet. The slits provided in the vicinity of the center and the outer periphery, and the ejection port of the external supporting combustible gas is composed of a slit having a plurality of conducting holes in the disk, and the gas ejection portion of the burner is located at the center. The mixed gas ejection nozzle,
A burner made of quartz glass comprising a combustible gas jetting slit, a combustible gas jetting circular slit, and a combustible gas jetting slit sequentially arranged as concentric circles extending outward from the center.