JPH0733471A - Method for drawing optical fiber - Google Patents
Method for drawing optical fiberInfo
- Publication number
- JPH0733471A JPH0733471A JP18164993A JP18164993A JPH0733471A JP H0733471 A JPH0733471 A JP H0733471A JP 18164993 A JP18164993 A JP 18164993A JP 18164993 A JP18164993 A JP 18164993A JP H0733471 A JPH0733471 A JP H0733471A
- Authority
- JP
- Japan
- Prior art keywords
- optical fiber
- cap
- glass preform
- glass
- furnace
- 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.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
- C03B37/01—Manufacture of glass fibres or filaments
- C03B37/02—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor
- C03B37/025—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor from reheated softened tubes, rods, fibres or filaments, e.g. drawing fibres from preforms
- C03B37/027—Fibres composed of different sorts of glass, e.g. glass optical fibres
- C03B37/02736—Means for supporting, rotating or feeding the tubes, rods, fibres or filaments to be drawn, e.g. fibre draw towers, preform alignment, butt-joining preforms or dummy parts during feeding
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は、光ファイバの線引き方
法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber drawing method.
【0002】[0002]
【従来技術】光ファイバ用ガラス母材から光ファイバを
線引きする方法としては、図3に示すような線引き装置
を用いておこなわれることが一般的であった。まず、別
工程にて製造された光ファイバ用ガラス母材1を保持部
材2にて垂直に保持する。次いで、前記光ファイバ用ガ
ラス母材1を前記保持部材2によって所定の速度で下降
させ、加熱線引き炉3内にその下端から導入する。ま
た、加熱線引き炉3は、上蓋部4、炉心管5および下蓋
部6からなり、炉心管5の外側には電気ヒータなどの加
熱源7を具備している。また、前記炉心管5内には、内
部雰囲気の清浄化、外部雰囲気の吸引防止などを目的と
して不活性ガス、具体的にはArガスなどが不活性ガス
供給口8から供給されている。そして、この加熱線引き
炉3内において前記光ファイバ用ガラス母材1はその下
端から上端へと徐々に加熱溶融されつつ、図示しない下
方のキャプスタンにより引き取られることによって線引
きされ、光ファイバ9となる。2. Description of the Related Art As a method for drawing an optical fiber from a glass preform for an optical fiber, it has been general to use a drawing device as shown in FIG. First, the glass base material 1 for an optical fiber manufactured in another process is vertically held by the holding member 2. Next, the glass preform 1 for optical fibers is lowered at a predetermined speed by the holding member 2 and introduced into the heating wire drawing furnace 3 from its lower end. The heating wire drawing furnace 3 is composed of an upper lid part 4, a core tube 5 and a lower lid part 6, and a heating source 7 such as an electric heater is provided outside the core tube 5. In addition, an inert gas, specifically, Ar gas or the like is supplied from the inert gas supply port 8 into the core tube 5 for the purpose of cleaning the internal atmosphere and preventing suction of the external atmosphere. Then, in the heating drawing furnace 3, the glass preform 1 for optical fiber is gradually heated and melted from its lower end to its upper end and drawn by a lower capstan (not shown) to be drawn into an optical fiber 9. .
【0003】しかしながら、前述した線引き装置を用い
る方法では、前記光ファイバ用ガラス母材1の残りが少
なくなると、線引きによって得られる光ファイバ9の外
径変動が大きくなってしまった。この原因は、前記光フ
ァイバ用ガラス母材1の上端部分がテーパ形状であるた
めに前記上蓋部4の内径と光ファイバ用ガラス母材1の
外径との差が該光ファイバ用ガラス母材1の外径が定常
状態である部分よりも大きくなってしまうことに関係が
あった。具体的には、前記上蓋部4と前記光ファイバ用
ガラス母材1との隙間aが大きくなってしまい、前記炉
心管5内に流れる不活性ガスが外部へと流れやすくな
り、結果として該炉心管5内の不活性ガスの流れに変化
が生じ、線引きされて得られる光ファイバ9に大きな外
径変動を生じさせる原因となっていた。However, in the method using the above-mentioned drawing apparatus, when the remaining amount of the optical fiber glass preform 1 is reduced, the outer diameter variation of the optical fiber 9 obtained by drawing becomes large. This is because the upper end portion of the glass preform 1 for optical fiber has a tapered shape, and therefore the difference between the inner diameter of the upper lid 4 and the outer diameter of the glass preform 1 for optical fiber is the glass preform for optical fiber. It was related to the fact that the outer diameter of 1 became larger than the portion in the steady state. Specifically, the gap a between the upper lid 4 and the glass preform 1 for optical fiber becomes large, and the inert gas flowing in the core tube 5 easily flows to the outside, resulting in the core. The flow of the inert gas in the tube 5 is changed, which causes a large fluctuation of the outer diameter of the optical fiber 9 obtained by drawing.
【0004】この問題を解決すべく、従来は、図2
(b)に示すような石英ガラス製のキャップ10を図2
(a)に示すように光ファイバ用ガラス母材1の上端部
分に被せ、見かけ上外径が一定になるようにして光ファ
イバの線引きをおこなっていた。このキャップ10を用
いることによって、該光ファイバ用ガラス母材1の外径
が定常状態である部分に比べて前記上蓋部4と前記光フ
ァイバ用ガラス母材1との隙間aは大きくならず、前記
炉心管5内の不活性ガスの流れが不安定になることはな
くなった。そのため、線引きされる光ファイバ9にも大
きな外径変動は見られなかった。In order to solve this problem, the conventional method shown in FIG.
The cap 10 made of quartz glass as shown in FIG.
As shown in (a), an optical fiber was drawn by covering the upper end portion of the optical fiber glass preform 1 so that the outer diameter was apparently constant. By using this cap 10, the gap a between the upper lid portion 4 and the optical fiber glass preform 1 does not become larger than the portion where the outer diameter of the optical fiber glass preform 1 is in a steady state, The flow of the inert gas in the core tube 5 is no longer unstable. Therefore, no large outer diameter fluctuation was observed in the drawn optical fiber 9.
【0005】[0005]
【発明が解決しようとする課題】ところが、前述した従
来の方法では光ファイバ用ガラス母材とキャップが加熱
線引き炉内に導入された際に、その熱によって加熱融着
してしまうという新たな問題がおこった。したがって、
キャップを光ファイバ用ガラス母材から切り離すことが
出来ず、該キャップの再利用ができなかった。また、従
来の方法では、線引き途中からキャップが邪魔になっ
て、光ファイバ用ガラス母材としての品質は悪くなくて
も線引きすることができずに廃棄している部分があっ
た。However, in the above-mentioned conventional method, when the glass base material for an optical fiber and the cap are introduced into the heating wire drawing furnace, they are heated and fused by the heat, which is a new problem. Happened. Therefore,
The cap could not be separated from the glass preform for optical fiber, and the cap could not be reused. Further, in the conventional method, the cap interferes during the drawing process, and even if the quality of the glass preform for optical fiber is not bad, it cannot be drawn and is discarded.
【0006】しかしながら、近年の技術の進歩により製
造される光ファイバ用ガラス母材が大型化されているこ
とにともなって、この廃棄している部分も非常に多くな
ってきている。これらの理由により、経済的なコストを
低減することは難しかった。そこで、ガラスキャップの
再利用を可能とし、かつ光ファイバ用ガラス母材を有効
に線引きすることができ、結果として経済的コストを低
減することができる光ファイバの線引き方法を開発する
ことが緊急の課題とされていた。However, as the glass base material for optical fibers manufactured by the recent technological advances has been increased in size, the number of the discarded parts has also become very large. For these reasons, it was difficult to reduce the economic cost. Therefore, it is urgent to develop an optical fiber drawing method that enables reuse of a glass cap, can effectively draw an optical fiber glass preform, and can reduce economic cost as a result. It was an issue.
【0007】[0007]
【課題を解決するための手段】本発明は、不活性ガスの
流れを乱すことなく、光ファイバ用ガラス母材とキャッ
プとが融着せず、かつ光ファイバ用ガラス母材を有効に
線引きすることができる光ファイバの線引き方法を提供
することを目的とする。前述した目的を達成すべく、本
発明は光ファイバ用ガラス母材の上端にキャップを被せ
て光ファイバを線引きする方法において、前記光ファイ
バ用ガラス母材と前記キャップとの間に隙間調節部材を
設けることを特徴とする。DISCLOSURE OF THE INVENTION According to the present invention, an optical fiber glass preform is not fused with a cap without disturbing the flow of an inert gas, and an optical fiber glass preform is effectively drawn. It is an object of the present invention to provide a method for drawing an optical fiber that enables In order to achieve the above-mentioned object, the present invention is a method for drawing an optical fiber by covering an upper end of an optical fiber glass preform with a cap, wherein a gap adjusting member is provided between the optical fiber glass preform and the cap. It is characterized in that it is provided.
【0008】[0008]
【作用】本発明のように、光ファイバ用ガラス母材とキ
ャップとの間に隙間調節部材を設置すれば、前記光ファ
イバ用ガラス母材と前記キャップとが直接接触しないの
で、両者が加熱線引き炉内で融着されることがなくな
る。このため、キャップの再利用が可能となった。さら
に従来よりも、キャップの下端が上方に移動したので、
線引き途中でキャップが邪魔となって品質的に有効であ
る部分が線引きできない、ということもなくなった。し
たがって、より有効に光ファイバ用ガラス母材を線引き
することができる。If a gap adjusting member is installed between the optical fiber glass preform and the cap as in the present invention, the optical fiber glass preform and the cap do not come into direct contact with each other. It will not be fused in the furnace. Therefore, the cap can be reused. Furthermore, since the lower end of the cap has moved upward compared to the past,
There is no longer a problem that the cap is an obstacle during the drawing process and the part that is qualitatively effective cannot be drawn. Therefore, the glass preform for optical fibers can be more effectively drawn.
【0009】[0009]
【実施例】以下、本発明の実施例を図面を参照して詳細
に説明する。実施例1としては、図1のような線引き装
置を用いて光ファイバ用ガラス母材1を線引きして光フ
ァイバ9を製造した。すなわち、図1(b)に示すよう
な石英ガラス製のキャップ10および石英ガラス製の隙
間調節部材11を図1(a)に示すように光ファイバ用
ガラス母材1に付けた後、保持部材2にて垂直に保持さ
せた。ところでこの隙間調節部材11は中心に前記光フ
ァイバ用ガラス母材1の支持棒が貫通する貫通口20を
有し、上端にキャップ10の上端内面に接するフランジ
21を具備する筒状体形状を有している。そしてこれの
高さを適宜選択して前記光ファイバ用ガラス母材1と前
記キャップ10との間の隙間bの量を調節する。次い
で、前記保持部材2によって光ファイバ用ガラス母材1
を下降させ、加熱線引き炉3内にその下端から導入し
た。加熱線引き炉3は、上蓋部4、炉心管5および下蓋
部6からなり、炉心管5の外側には加熱源7、具体的に
は電気ヒータを具備していた。また、炉心管5内には、
内部雰囲気の清浄化、外部雰囲気の吸引防止などを目的
として不活性ガス、具体的にはArガスが不活性ガス供
給口8から供給されていた。Embodiments of the present invention will now be described in detail with reference to the drawings. As Example 1, an optical fiber 9 was manufactured by drawing the optical fiber glass preform 1 using a drawing apparatus as shown in FIG. That is, after attaching the cap 10 made of quartz glass and the gap adjusting member 11 made of quartz glass as shown in FIG. 1B to the glass preform 1 for optical fiber as shown in FIG. It was held vertically at 2. By the way, the gap adjusting member 11 has a tubular body shape having a through hole 20 through which the support rod of the optical fiber glass preform 1 penetrates in the center and a flange 21 in contact with the inner surface of the upper end of the cap 10 at the upper end. is doing. Then, the height thereof is appropriately selected to adjust the amount of the gap b between the optical fiber glass preform 1 and the cap 10. Then, the glass base material 1 for optical fiber is held by the holding member 2.
Was lowered and introduced into the heating wire drawing furnace 3 from its lower end. The heating wire drawing furnace 3 was composed of an upper lid part 4, a furnace core tube 5 and a lower lid part 6, and a heating source 7, specifically, an electric heater was provided outside the furnace core tube 5. In the core tube 5,
An inert gas, specifically, Ar gas was supplied from the inert gas supply port 8 for the purpose of cleaning the internal atmosphere and preventing suction of the external atmosphere.
【0010】前述した線引き装置にて光ファイバ用ガラ
ス母材1から光ファイバ9を線引きした結果、該光ファ
イバ9には外径変動は殆ど見られなかった。また、光フ
ァイバ用ガラス母材1とキャップ10との間に隙間bを
設けたので、線引き中に前記キャップ10が邪魔になる
こともなく、品質的に適切である部分はすべて線引きす
ることができた。さらに、光ファイバ用ガラス母材1と
キャップ10とは接触していないので両者が融着されて
しまうこともなかった。したがって、線引き終了後に切
り離したキャップを別途再利用することができた。As a result of drawing the optical fiber 9 from the glass base material 1 for an optical fiber with the above-described drawing device, almost no change in outer diameter was observed in the optical fiber 9. Further, since the gap b is provided between the optical fiber glass preform 1 and the cap 10, the cap 10 does not get in the way during drawing, and it is possible to draw all the parts of suitable quality. did it. Further, since the optical fiber glass base material 1 and the cap 10 are not in contact with each other, neither of them is fused. Therefore, the cap separated after the drawing was able to be reused separately.
【0011】なお、キャップ10と光ファイバ用ガラス
母材1との隙間bは、上蓋部4の厚さcよりも小さくし
た。これは、前記隙間bが前記上蓋部4の厚さcより大
きいと、前記上蓋部4付近を前記隙間が通過する際に、
前記上蓋部4と前記光ファイバ用ガラス母材1との隙間
の大きさが変化して、炉心管5内の不活性ガスの流れか
たが不安定となり、結果として線引きした光ファイバに
外径変動が生じ易いからである。The gap b between the cap 10 and the optical fiber glass base material 1 is smaller than the thickness c of the upper lid 4. This is because when the gap b is larger than the thickness c of the upper lid portion 4, when the gap passes near the upper lid portion 4,
The size of the gap between the upper lid portion 4 and the optical fiber glass preform 1 changes, and the flow of the inert gas in the core tube 5 becomes unstable, and as a result, the drawn optical fiber has an outer diameter. This is because fluctuation easily occurs.
【0012】以下、本発明の比較例を説明する。比較例
としては、図2のような線引き装置を用いて光ファイバ
用ガラス母材1を線引きして光ファイバ9を製造した。
すなわち、光ファイバ用ガラス母材1に石英ガラス製の
キャップ10を付けた後、保持部材2にて垂直に保持し
た。次いで、該光ファイバ用ガラス母材1を前記保持部
材2によって下降させ、加熱線引き炉3内にその下端か
ら導入した。また、該加熱線引き炉3は、上蓋部4、炉
心管5および下蓋部6からなり、該炉心管5の外側には
加熱源7、具体的には電気ヒータを具備している。ま
た、該炉心管5内には、内部雰囲気の清浄化、外部雰囲
気の吸引防止などを目的として不活性ガス、具体的には
Arガスが不活性ガス供給口8から供給されていた。A comparative example of the present invention will be described below. As a comparative example, an optical fiber 9 was manufactured by drawing the optical fiber glass preform 1 using a drawing apparatus as shown in FIG.
That is, after the silica glass cap 10 was attached to the optical fiber glass base material 1, it was held vertically by the holding member 2. Then, the glass preform 1 for optical fibers was lowered by the holding member 2 and introduced into the heating wire drawing furnace 3 from the lower end thereof. The heating wire drawing furnace 3 is composed of an upper lid portion 4, a furnace core tube 5 and a lower lid portion 6, and a heating source 7, specifically, an electric heater is provided outside the furnace core tube 5. In addition, an inert gas, specifically, an Ar gas was supplied from the inert gas supply port 8 into the furnace core tube 5 for the purpose of cleaning the internal atmosphere and preventing suction of the external atmosphere.
【0013】前述した装置を用い、かつ種々の線引き条
件はすべて実施例と同様にして光ファイバ9を製造し
た。その結果、得られた光ファイバ9の外径変動値は、
実施例で得られた光ファイバと比べても遜色がなかっ
た。しかしながら、線引き中にキャップ10が邪魔にな
って品質的に適切であっても線引きできない部分があっ
た。また前記キャップ10と光ファイバ用ガラス母材1
とが加熱線引き炉3内で融着されてしまい、両者を切り
離すことができなかったので、前記キャップ10を再利
用することができなかった。An optical fiber 9 was manufactured using the above-mentioned apparatus and under the same drawing conditions as in Example 1. As a result, the obtained outer diameter variation value of the optical fiber 9 is
It was comparable to the optical fibers obtained in the examples. However, there was a portion where the cap 10 was an obstacle during drawing and could not be drawn even if the quality was appropriate. Further, the cap 10 and the glass base material 1 for optical fiber
And 10 were fused in the heating wire drawing furnace 3 and could not be separated from each other, so that the cap 10 could not be reused.
【0014】ところで、本実施例ではキャップおよび隙
間調節部材として、石英ガラス製のものを使用したが、
これはアルミナやジルコニアなどのセラミックス製でも
よいし、モリブデンなどの高融点金属でもよい。また、
キャップと隙間調節部材を一体化したものを使用して光
ファイバ用ガラス母材を線引きしてもよいことは明らか
である。By the way, in this embodiment, the cap and the gap adjusting member are made of quartz glass.
This may be made of ceramics such as alumina or zirconia, or may be a refractory metal such as molybdenum. Also,
It is obvious that the glass preform for optical fibers may be drawn using an integrated cap and gap adjusting member.
【0015】[0015]
【発明の効果】本発明によれば、光ファイバ用ガラス母
材を無駄なく線引きし、経済的なコストを低減すること
が可能な光ファイバの線引き方法が提供される。According to the present invention, there is provided an optical fiber drawing method capable of drawing an optical fiber glass preform without waste and reducing the economical cost.
【図1】図1(a)は、本発明に係わる光ファイバの線
引き装置の一例である。図1(b)は、本発明に係わる
キャップおよび隙間調節部材である。FIG. 1A is an example of an optical fiber drawing apparatus according to the present invention. FIG. 1B shows a cap and a gap adjusting member according to the present invention.
【図2】図2(a)は、比較例で用いた光ファイバの線
引き装置である。図2(b)は、比較例で用いたキャッ
プである。FIG. 2A is an optical fiber drawing device used in a comparative example. FIG. 2B shows the cap used in the comparative example.
【図3】図3は、従来の光ファイバの線引き装置であ
る。FIG. 3 is a drawing apparatus of a conventional optical fiber.
1…光ファイバ用ガラス母材 2…保持部材 3…加熱線引き炉 4…上蓋部 5…炉心管 6…下蓋部 7…加熱源 8…不活性ガス供給口 9…光ファイバ 10…キャップ 11…隙間調節部材 20…貫通口 21…フランジ DESCRIPTION OF SYMBOLS 1 ... Glass base material for optical fibers 2 ... Holding member 3 ... Heating wire drawing furnace 4 ... Upper lid part 5 ... Reactor core tube 6 ... Lower lid part 7 ... Heating source 8 ... Inert gas supply port 9 ... Optical fiber 10 ... Cap 11 ... Gap adjusting member 20 ... Through hole 21 ... Flange
Claims (1)
プを被せて光ファイバを線引きする方法において、前記
光ファイバ用ガラス母材と前記キャップとの間に隙間調
節部材を設けることを特徴とする光ファイバの線引き方
法。1. A method of drawing an optical fiber by covering an upper end of an optical fiber glass preform with a cap, wherein a gap adjusting member is provided between the optical fiber glass preform and the cap. Optical fiber drawing method.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP18164993A JPH0733471A (en) | 1993-07-22 | 1993-07-22 | Method for drawing optical fiber |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP18164993A JPH0733471A (en) | 1993-07-22 | 1993-07-22 | Method for drawing optical fiber |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH0733471A true JPH0733471A (en) | 1995-02-03 |
Family
ID=16104440
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP18164993A Pending JPH0733471A (en) | 1993-07-22 | 1993-07-22 | Method for drawing optical fiber |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0733471A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1655271A2 (en) * | 1997-06-19 | 2006-05-10 | Shin-Etsu Chemical Company, Ltd. | Method and apparatus for drawing a class ingot |
JP2015074600A (en) * | 2013-10-11 | 2015-04-20 | 住友電気工業株式会社 | Method of manufacturing optical fiber |
WO2018101228A1 (en) * | 2016-11-30 | 2018-06-07 | 住友電気工業株式会社 | Seal structure for optical fiber wire drawing oven and optical fiber production method |
US20220315473A1 (en) * | 2021-04-06 | 2022-10-06 | Corning Incorporated | Optical fiber draw furnace system and method |
-
1993
- 1993-07-22 JP JP18164993A patent/JPH0733471A/en active Pending
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
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EP1655271A2 (en) * | 1997-06-19 | 2006-05-10 | Shin-Etsu Chemical Company, Ltd. | Method and apparatus for drawing a class ingot |
EP1655271A3 (en) * | 1997-06-19 | 2006-06-07 | Shin-Etsu Chemical Company, Ltd. | Method and apparatus for drawing a class ingot |
JP2015074600A (en) * | 2013-10-11 | 2015-04-20 | 住友電気工業株式会社 | Method of manufacturing optical fiber |
CN104556677A (en) * | 2013-10-11 | 2015-04-29 | 住友电气工业株式会社 | Manufacturing method of fiber |
WO2018101228A1 (en) * | 2016-11-30 | 2018-06-07 | 住友電気工業株式会社 | Seal structure for optical fiber wire drawing oven and optical fiber production method |
CN110035980A (en) * | 2016-11-30 | 2019-07-19 | 住友电气工业株式会社 | The manufacturing method of the seal construction of optical fiber fiber drawing furnace, optical fiber |
KR20190086475A (en) * | 2016-11-30 | 2019-07-22 | 스미토모 덴키 고교 가부시키가이샤 | Seal structure of wire drawing furnace for optical fiber, manufacturing method of optical fiber |
RU2745625C2 (en) * | 2016-11-30 | 2021-03-29 | Сумитомо Электрик Индастриз, Лтд. | Sealing device for an extracting optical fiber oven and a method for obtaining optical fiber |
CN110035980B (en) * | 2016-11-30 | 2021-08-24 | 住友电气工业株式会社 | Sealing structure of optical fiber drawing furnace and method for manufacturing optical fiber |
US20220315473A1 (en) * | 2021-04-06 | 2022-10-06 | Corning Incorporated | Optical fiber draw furnace system and method |
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