JPH0712953B2 - Method for manufacturing base material for optical fiber - Google Patents
Method for manufacturing base material for optical fiberInfo
- Publication number
- JPH0712953B2 JPH0712953B2 JP18697286A JP18697286A JPH0712953B2 JP H0712953 B2 JPH0712953 B2 JP H0712953B2 JP 18697286 A JP18697286 A JP 18697286A JP 18697286 A JP18697286 A JP 18697286A JP H0712953 B2 JPH0712953 B2 JP H0712953B2
- Authority
- JP
- Japan
- Prior art keywords
- burner
- outer diameter
- protective tube
- base material
- flame
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Landscapes
- Light Guides In General And Applications Therefor (AREA)
- Glass Melting And Manufacturing (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は光フアイバ用母材の製造方法に関するものであ
る。TECHNICAL FIELD The present invention relates to a method for producing a base material for optical fibers.
一般に火炎加水分解反応を用いた光フアイバ用母材の製
造においては、バーナから燃焼ガス、ガラス原料等を噴
出し、酸水素火炎中において上記ガラス原料の加水分解
反応により生じたガラス微粒子を回転する出発材または
心棒の外周上に堆積させる方法が用いられる。この方法
で母材を作るにはバーナの寸法、原料、燃焼ガスの流
量、バーナと母材堆積面との間隔を最適に設定しなけれ
ばならない。Generally, in the production of optical fiber preforms using flame hydrolysis reaction, combustion gas, glass raw materials, etc. are jetted from a burner to rotate glass fine particles generated by the hydrolysis reaction of the above glass raw materials in an oxyhydrogen flame. A method of depositing on the outer circumference of the starting material or mandrel is used. In order to produce the base metal by this method, it is necessary to optimally set the size of the burner, the raw material, the flow rate of the combustion gas, and the distance between the burner and the base metal deposition surface.
ここでいう最適とは、ガラス微粒子の堆積効率〔堆積速
度（g/分）／原料投入量（SiO2換算量）（g/分）〕が最
良で、かつプロセスの安定度が高く、再現性良く多孔質
母材を製造できることである。なお、堆積速度＝１分間
当りのSiO2堆積量（ｇ）である。Optimum here means that the deposition efficiency of glass particles [deposition rate (g / min) / feeding amount of raw material (SiO 2 conversion amount) (g / min)] is the best, process stability is high, and reproducibility is high. That is, the porous base material can be manufactured well. Note that the deposition rate is the SiO 2 deposition amount (g) per minute.
〔発明が解決しようとする問題点〕 従来のこの種の製造方法は、原料流量を多くしていくと
得られる多孔質母材が大型化していく傾向がある。しか
し、母材の大きさに対してバーナが形成する火炎が小さ
いと多孔質母材がその形状を維持できなく割れてしまう
という問題がある。逆にバーナの火炎を径方向に広げて
しまうと炎中のガラス微粒子が拡散して、堆積効率が低
下するという問題も起つてくる。[Problems to be Solved by the Invention] In the conventional manufacturing method of this type, the porous base material obtained tends to increase in size as the raw material flow rate increases. However, if the flame formed by the burner is smaller than the size of the base material, the porous base material cannot maintain its shape and is cracked. On the contrary, if the flame of the burner is expanded in the radial direction, the fine glass particles in the flame will diffuse and the deposition efficiency will decrease.
本発明は上記のいずれの問題も解決して高品質な大型母
材を堆積効率良く安定に製造できる新規な方法を意図し
たものである。The present invention is intended to solve any of the problems described above and to provide a novel method capable of stably producing a high-quality large-sized base material with high deposition efficiency.
本発明はバーナの火炎の径方向の広がり量を制御するこ
とにより、上記問題点を解決しようとするものであり、
気体のガラス原料を燃焼バーナから火炎中に噴出させて
火炎加水分解し、これにより生成するガラス微粒子を回
転する出発材又は心棒の外周に堆積させて回転軸方向に
助長させ多孔質ガラス母材を製造する方法において、上
記バーナの外周にバーナの火炎を保護する保護管を２重
に設け、内部保護管の外径はバーナ外径より大きく且つ
外部保護管の外径は該内部保護管の外径より大きく、該
２重の保護管の長さをそれぞれ調節することにより火炎
中のガラス微粒子の拡散を制御しつつ行うことを特徴と
する光フアイバ用母材の製造方法である。The present invention is intended to solve the above problems by controlling the amount of spread of the flame of the burner in the radial direction,
Gaseous glass raw material is jetted into the flame from the combustion burner to undergo flame hydrolysis, and the glass particles produced by this are deposited on the outer periphery of the rotating starting material or mandrel and promoted in the rotational axis direction to form the porous glass base material. In the manufacturing method, a protective tube for protecting flames of the burner is double provided on the outer circumference of the burner, the outer diameter of the inner protective tube is larger than the outer diameter of the burner, and the outer diameter of the outer protective tube is outside of the inner protective tube. A method for producing a base material for optical fibers, which is performed while controlling the diffusion of glass particles in a flame by adjusting the lengths of the double protective tubes each having a diameter larger than the diameter.
以下、本発明を図を参照して具体的に説明する。第１図
は本発明に用いるバーナの一例を示す図であつて、多重
管バーナ１の外周に内部保護管２を設け、さらにその外
周に外部保護管３を設けて、それぞれの管の火炎方向の
長さを調節することにより行う。この内部保護管２の外
径は、バーナ１の外径よりも大きく、外部保護管３の外
径は、内部保護管２の外径よりも大きい。Hereinafter, the present invention will be specifically described with reference to the drawings. FIG. 1 is a view showing an example of a burner used in the present invention, in which an inner protective tube 2 is provided on the outer circumference of a multi-tube burner 1, and an outer protective tube 3 is further provided on the outer circumference thereof, so that the flame direction of each tube This is done by adjusting the length of. The outer diameter of the inner protective tube 2 is larger than the outer diameter of the burner 1, and the outer diameter of the outer protective tube 3 is larger than the outer diameter of the inner protective tube 2.
本発明の基本的な作用を説明する。内部保護管２はバー
ナからの火炎の径方向の広がりを抑制するためのもの
で、火炎中のガラス微粒子の拡散を抑え、収束性を保つ
働きをする。外部保護管３は、母材近傍での火炎を径方
向に広げることにより、母材表面を広範囲にわたつて加
熱するようにする働きがある。この２つの保護管２及び
３の働きを組み合わせることにより、堆積効率を高く保
ち、大型母材を安定に製造することができる。The basic operation of the present invention will be described. The internal protective tube 2 is for suppressing the spread of the flame from the burner in the radial direction, and has a function of suppressing the diffusion of the glass particles in the flame and maintaining the convergence. The external protective tube 3 has a function of spreading the flame in the vicinity of the base material in the radial direction to heat the base material surface over a wide range. By combining the functions of these two protective tubes 2 and 3, the deposition efficiency can be kept high and a large preform can be manufactured stably.
さらに、２重の保護管２及び３の長さをそれぞれ独立に
調節することにより、バーナ寸法、原料、燃料ガス流量
に応じて、最良な条件が得られるようにすることができ
る。この２重の保護管の長さをいろいろ変えた場合の母
材製造に与える影響を調べた結果を以下に示す。Further, by independently adjusting the lengths of the double protection tubes 2 and 3, it is possible to obtain the best condition depending on the burner size, the raw material, and the fuel gas flow rate. The results of investigating the influence on the base material production when various lengths of the double protective tube are changed are shown below.
第１図に示したような２重の保護管を設けた４重管バー
ナにおいて、中心の第１ポートの原料SiCl4を2l/分、２
ポートにH26l/分を、第３ポートにAr2l/分を、第４ポー
トにO210l/分を送り込み、多孔質母材を製造した。な
お、このバーナ１の外径は30mm、内部保護管２の径は40
mm、長さl1mm、外部保護管３の径は50mm、長さl2mmであ
る。In a quadruple burner equipped with a double protection tube as shown in Fig. 1, 2 l / min of raw material SiCl 4 in the first port at the center, 2
H 2 6 l / min was fed into the port, Ar 2 l / min was fed into the third port, and O 2 10 l / min was fed into the fourth port to manufacture a porous base material. The burner 1 has an outer diameter of 30 mm and the inner protective tube 2 has a diameter of 40 mm.
mm, the length l 1 mm, the outer protective tube 3 has a diameter of 50 mm and a length l 2 mm.
第２図（Ａ）及び（Ｂ）は、前記の条件において内部保
護管の長さl1を50mmに固定して、外部保護管長l2を変え
た時の母材外径と堆積効率を示したものである。外部保
護管は20mmの時、堆積効率が最良となることが分る。2 (A) and 2 (B) show the outer diameter of the base metal and the deposition efficiency when the length l 1 of the inner protective tube was fixed to 50 mm and the outer protective tube length l 2 was changed under the above conditions. It is a thing. It can be seen that the deposition efficiency is best when the outer protection tube is 20 mm.
第３図（Ａ）及び（Ｂ）は、l1とl2の和を70mmに固定し
て、l2を変えた時の堆積効率と母材外径とを示したもの
であり、l2が30mmの時、堆積効率が最良となることが分
る。また内部保護管のみ（l1＝70mm、l2＝0mm）の場合
は大型母材が形成できず、堆積効率が悪い。逆に、外部
保護管のみ（l2＝70mm）の場合は、母材は大型になる
が、堆積効率は悪い。これは、前者は火炎が広がらない
ためであり、後者はガラス微粒子が拡散してしまうため
である。しかも、内部保護管のみの場合は、保護管先端
の内側にガラス微粒子が付着しやすいが、外部保護管は
外径が大きく、これを取りつけることにより、ガラス微
粒子の付着を防げる。これにより、母材製造の安定性お
よび品質の安定性を長期保つことができる。Figure 3 (A) and (B), to fix the sum of l 1 and l 2 to 70 mm, it is limited to showing the deposition efficiency and preform outer diameter when varying l 2, l 2 It can be seen that the deposition efficiency is best when is 30 mm. Also, in the case of only the internal protective tube (l 1 = 70 mm, l 2 = 0 mm), a large base material cannot be formed and the deposition efficiency is poor. On the contrary, when only the external protection tube (l 2 = 70 mm) is used, the base material becomes large, but the deposition efficiency is poor. This is because the flame does not spread in the former, and the glass fine particles diffuse in the latter. Moreover, in the case of only the inner protective tube, the glass particles are likely to adhere to the inside of the tip of the protective tube, but the outer protective tube has a large outer diameter, and by attaching this, the adhesion of the glass particles can be prevented. This makes it possible to maintain the stability of the base material production and the stability of the quality for a long period of time.
本発明において保護管の外径は、重要な製造プロセス変
量である。内部保護管径r2は、火炎の広がりを抑制する
という主目的のため、バーナ外径r1に比べてそれほど大
きくすることはできない。通常、１〜1.5倍が好まし
い。それに対し、外部保護管は、火炎を広げ、大型母材
表面を広範囲に渡つて加熱することが主目的のため、バ
ーナ外径の1.2〜2.2倍が好ましい。In the present invention, the outer diameter of the protective tube is an important manufacturing process variable. The inner protection tube diameter r 2 cannot be made so large as compared with the burner outer diameter r 1 for the main purpose of suppressing the spread of flame. Usually, 1 to 1.5 times is preferable. On the other hand, the external protection tube is preferably 1.2 to 2.2 times the outer diameter of the burner because the main purpose is to spread the flame and heat the surface of the large base material over a wide range.
以上のように、火炎の保護管を２重にし、それぞれの長
さを調節することにより、最良の製造条件を維持するこ
とができる。As described above, the best manufacturing conditions can be maintained by making the flame protection tube double and adjusting the length of each tube.
第１図において、燃焼バーナの第１ポートに原料SiCl4
を2l/分、第２ポートにH2を6l/分を、第３ポートにArを
2l/分、第４ポートにO210l/分を送り込み多孔質母材を
製造した。In Fig. 1, the raw material SiCl 4 was added to the first port of the combustion burner.
2 l / min, H 2 at port 2 6 l / min, Ar at port 3
2 l / min and O 2 10 l / min were sent to the 4th port to manufacture a porous base material.
このバーナの外径は30mmでその先端に外径40mmの内部保
護管のみを50mmの長さにして設けた。この時の母材外径
は135mmで堆積効率は57％であつた。The outer diameter of this burner was 30 mm, and only the internal protective tube with an outer diameter of 40 mm was provided at the tip with a length of 50 mm. At this time, the outer diameter of the base material was 135 mm and the deposition efficiency was 57%.
この内部保護管の先端にさらに50mmの外部保護管を20mm
長さに取りつけたところ、得られた母材の外径は152mm
と大型化し、堆積効率は67％と約1.2倍大きくなつた。
この結果から本発明が母材外径を大型化し、かつ堆積効
率も向上できることが明らかである。An additional 50 mm external protection tube is added to the tip of this internal protection tube by 20 mm.
When attached to the length, the outer diameter of the obtained base material is 152 mm
And the deposition efficiency was 67%, 1.2 times larger.
From this result, it is clear that the present invention can increase the outer diameter of the base material and improve the deposition efficiency.
以上説明したように、本発明は燃焼バーナの先端に保護
管を２重に設け、さらにその長さをそれぞれ調節するこ
とにより、多孔質母材を最良の堆積効率で、しかも、高
品質の大型の母材を安定に製造できる。As described above, according to the present invention, the protection tube is provided in double at the tip of the combustion burner, and the lengths of the protection tubes are adjusted respectively, so that the porous base material has the best deposition efficiency and is of high quality and large size. The base material can be stably manufactured.
第１図は本発明に用いる２重保護管を設けた燃焼バーナ
の説明図、 第２図（Ａ）及び（Ｂ）はそれぞれ外部保護管の長さl2
（mm）のみを変化させたときの堆積効率及び母材外径の
変化を示すグラフである。 第３図（Ａ）及び（Ｂ）はそれぞれ外部保護管長と内部
保護管長の和を一定にして外部保護管長を変化させたと
きの堆積効率及び母材外径の変化を示すグラフである。FIG. 1 is an explanatory view of a combustion burner provided with a double protection tube used in the present invention, and FIGS. 2 (A) and 2 (B) are respectively the length l 2 of the outer protection tube.
6 is a graph showing changes in deposition efficiency and base material outer diameter when only (mm) is changed. FIGS. 3 (A) and 3 (B) are graphs showing changes in the deposition efficiency and the outer diameter of the base material when the outer protective tube length is changed while keeping the sum of the outer protective tube length and the inner protective tube length constant.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 昭60−137839（ＪＰ，Ａ) 特開 昭60−239340（ＪＰ，Ａ) 特公 昭59−19892（ＪＰ，Ｂ２) ─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP 60-137839 (JP, A) JP 60-239340 (JP, A) JP 59-19892 (JP, B2)
Claims (1)
に噴出させて火炎加水分解し、これにより生成するガラ
ス微粒子を回転する出発材又は心棒の外周に堆積させて
回転軸方向に成長させ多孔質ガラス母材を製造する方法
において、上記バーナの外周にバーナの火炎を保護する
保護管を２重に設け、内部保護管の外径はバーナ外径よ
り大きく且つ外部保護管の外径は該内部保護管の外径よ
り大きく、該２重の保護管の長さをそれぞれ調節するこ
とにより火炎中のガラス微粒子の拡散を制御しつつ行う
ことを特徴とする光フアイバ用母材の製造方法。1. A gaseous glass raw material is jetted from a combustion burner into a flame to undergo flame hydrolysis, and glass fine particles produced thereby are deposited on the outer periphery of a rotating starting material or a mandrel to grow in the rotational axis direction to form a porous structure. In the method for producing a high quality glass preform, a protective tube for protecting the flame of the burner is double provided on the outer periphery of the burner, the outer diameter of the inner protective tube is larger than the outer diameter of the burner, and the outer diameter of the outer protective tube is larger than the outer diameter of the burner. A method for producing a base material for optical fibers, which is larger than the outer diameter of the inner protective tube and is controlled while controlling the diffusion of the glass particles in the flame by adjusting the lengths of the double protective tubes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18697286A JPH0712953B2 (en) | 1986-08-11 | 1986-08-11 | Method for manufacturing base material for optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18697286A JPH0712953B2 (en) | 1986-08-11 | 1986-08-11 | Method for manufacturing base material for optical fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6379055A JPS6379055A (en) | 1988-04-09 |
| JPH0712953B2 true JPH0712953B2 (en) | 1995-02-15 |
Family
ID=16197947
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18697286A Expired - Lifetime JPH0712953B2 (en) | 1986-08-11 | 1986-08-11 | Method for manufacturing base material for optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0712953B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0558661A (en) * | 1991-08-27 | 1993-03-09 | Fujikura Ltd | Production of parent material for optical fiber |
| JP6979915B2 (en) * | 2018-03-29 | 2021-12-15 | 古河電気工業株式会社 | Optical fiber porous base material manufacturing equipment and optical fiber porous base material manufacturing method |
-
1986
- 1986-08-11 JP JP18697286A patent/JPH0712953B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6379055A (en) | 1988-04-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR880001607B1 (en) | Preparation for making of glass fiber preform | |
| JP4498917B2 (en) | Method for producing glass rod | |
| US20140083140A1 (en) | Method of manufacturing porous glass deposition body for optical fiber | |
| JPH0712953B2 (en) | Method for manufacturing base material for optical fiber | |
| JP2612941B2 (en) | Method for producing porous optical fiber preform | |
| JP4742429B2 (en) | Method for producing glass particulate deposit | |
| JP3133392B2 (en) | Manufacturing method of soot base material for optical fiber | |
| JPS59174538A (en) | Manufacture of base material for optical fiber | |
| JP2000327341A (en) | Multiple pipe burner for producing porous glass base material and method and device for producing porous glass base material by use of the same | |
| JPS6044258B2 (en) | synthesis torch | |
| JPH03112820A (en) | Production of porous glass preform | |
| JP3137849B2 (en) | Manufacturing method of preform for dispersion shifted optical fiber | |
| JPS6259063B2 (en) | ||
| JPH0777968B2 (en) | Optical fiber preform base material manufacturing method | |
| JP4398114B2 (en) | Manufacturing method of glass base material for optical fiber with less unevenness | |
| JP3003173B2 (en) | Method for producing glass particle deposit | |
| JPH05319849A (en) | Production of silica porous preform | |
| JPS60260433A (en) | Manufacture of base material for optical fiber | |
| JP2004026610A (en) | Method for manufacturing porous preform for optical fiber | |
| JPS63107825A (en) | Production of synthetic quartz tube | |
| JP2000143275A (en) | Production of glass preform for optical fiber | |
| JPS63123828A (en) | Production of porous preform for optical fiber | |
| JP3758598B2 (en) | Method and apparatus for manufacturing porous glass base material | |
| JPS63285129A (en) | Production of optical fiber preform | |
| JPH09301719A (en) | Focusing multiple burner for synthesis of glass fine particle |