JP2618498B2 - Optical fiber manufacturing method - Google Patents
Optical fiber manufacturing methodInfo
- Publication number
- JP2618498B2 JP2618498B2 JP26596089A JP26596089A JP2618498B2 JP 2618498 B2 JP2618498 B2 JP 2618498B2 JP 26596089 A JP26596089 A JP 26596089A JP 26596089 A JP26596089 A JP 26596089A JP 2618498 B2 JP2618498 B2 JP 2618498B2
- Authority
- JP
- Japan
- Prior art keywords
- optical fiber
- fiber preform
- seal lid
- support rod
- lid
- 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
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
- C03B37/029—Furnaces therefor
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2205/00—Fibre drawing or extruding details
- C03B2205/60—Optical fibre draw furnaces
- C03B2205/80—Means for sealing the preform entry or upper end of the furnace
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)
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明は、光ファイバの製造方法に関するものであ
る。The present invention relates to a method for manufacturing an optical fiber.
［従来の技術］ 第３図は、従来の光ファイバ製造装置の一例を示した
ものである。該光ファイバ製造装置は、線引き炉１と、
該線引き炉１内で加熱されて光ファイバ２が線引きされ
る光ファイバ母材３と、光ファイバ２の外径を測定する
外径測定器４とを備えて構成されている。線引き炉１
は、炉体５を有し、該炉体５内には炉心管６が貫通支持
され、炉体５内で炉心管６の外周にはヒータ７が配置さ
れ、炉心管６の上端は上部シール８でシールされ、下端
は下部シール９でシールされている。炉心管６内には、
上部シール８の光ファイバ母材挿入口10から光ファイバ
母材３が挿入されている。炉心管６の上部ガス注入口11
と下部ガス注入口12から該炉心管６内にシールガスとし
てArガスの如き不活性ガスが注入され、該炉心管６内へ
の外部の空気の流入を抑制するようになっている。ま
た、炉体５の中部ガス注入口13から該炉体５内へシール
ガスとしてArガスの如き不活性ガスが注入され、カーボ
ン等よりなるヒータ７を保護するようになっている。[Prior Art] FIG. 3 shows an example of a conventional optical fiber manufacturing apparatus. The optical fiber manufacturing apparatus comprises: a drawing furnace 1;
An optical fiber preform 3 that is heated in the drawing furnace 1 to draw an optical fiber 2 and an outer diameter measuring device 4 that measures the outer diameter of the optical fiber 2 are provided. Drawing furnace 1
Has a furnace body 5, a furnace tube 6 is supported in the furnace body 5, a heater 7 is arranged on the outer periphery of the furnace tube 6 in the furnace body 5, and an upper end of the furnace tube 6 is sealed with an upper seal. The lower end is sealed with a lower seal 9. In the core tube 6,
The optical fiber preform 3 is inserted from the optical fiber preform insertion port 10 of the upper seal 8. Upper gas inlet 11 of core tube 6
Then, an inert gas such as Ar gas is injected as a seal gas into the furnace core tube 6 from the lower gas inlet 12 to suppress the inflow of external air into the furnace core tube 6. Further, an inert gas such as Ar gas is injected as a seal gas into the furnace body 5 from the central gas inlet 13 of the furnace body 5 so as to protect the heater 7 made of carbon or the like.
従来は、このような装置のヒータ７で光ファイバ母材
３を加熱し、該光ファイバ母材３の下部から光ファイバ
２の製造を行っていた。Conventionally, the optical fiber preform 3 is heated by the heater 7 of such an apparatus, and the optical fiber 2 is manufactured from below the optical fiber preform 3.
このようにして光ファイバ２の製造を行った場合、従
来の光ファイバ母材３のサイズは外径20〜35mm程度であ
り、線引き終りに近づいたとき、上部シール８とヒータ
７の最高温部即ちヒータ７の約半分の高さの位置Ａとの
間の寸法l1の長さの部分で光ファイバ母材３が引き残さ
れることになる。これは、約４図に示すように、光ファ
イバ母材３の上端に付いているサポート棒14が外径15〜
20mmと、光ファイバ母材３より細いため、光ファイバ母
材３が線引きにつれて下降してその上端部も炉心管６内
に入り、光ファイバ母材挿入口10を該サポート棒14が貫
通する状態になったとき、光ファイバ母材挿入口10とサ
ポート棒14との間のクリアランスが大きくなり過ぎ、シ
ール性が不十分になって、空気が炉心管６内へ侵入し、
炉を損傷するなどのトラブルを発生するためである。When the optical fiber 2 is manufactured in this manner, the conventional optical fiber preform 3 has an outer diameter of about 20 to 35 mm. that is, that the optical fiber preform 3 is left off at length of the dimension l 1 between approximately half the height of the position a of the heater 7. This is because the support rod 14 attached to the upper end of the optical fiber preform 3 has an outer diameter of 15 to
Since the optical fiber preform 3 is 20 mm, which is thinner than the optical fiber preform 3, the optical fiber preform 3 descends as it is drawn, the upper end also enters the furnace tube 6, and the support rod 14 passes through the optical fiber preform insertion port 10. , The clearance between the optical fiber preform insertion hole 10 and the support rod 14 becomes too large, the sealing performance becomes insufficient, and air enters the furnace core tube 6,
This is to cause troubles such as damaging the furnace.
サポート棒14を光ファイバ母材３と同径にして光ファ
イバ母材挿入口10との間のクリアランスを小さくするこ
とも考えられるが、コスト高になって経済性が悪く、ま
た重くなって取扱い性能が悪く、且つ全長が長くなって
危険であり、実施されていない。It is conceivable to reduce the clearance between the support rod 14 and the optical fiber preform insertion port 10 by making the diameter of the support rod 14 the same as that of the optical fiber preform 3, but the cost increases and the economical efficiency deteriorates. Poor performance, long overall length and dangerous, not implemented.
これを防止するため、第５図に示すように、光ファイ
バ母材３の上端に線引き炉１の引き残り寸法l1に相当す
る長さのダミー石英棒15を付けることもある。In order to prevent this, as shown in FIG. 5, a dummy quartz rod 15 having a length corresponding to the remaining length l 1 of the drawing furnace 1 may be attached to the upper end of the optical fiber preform 3.
［発明が解決しようとする課題］ しかしながら、近年、光ファイバ母材３のサイズは外
径45〜70mmの大径になってきており、第５図に示すダミ
ー付け法では、ダミー石英棒15の形成に、大量の酸素及
び水素と時間を要する問題点がある。例えば、バーナ２
本（H2＝150／分、O2＝75／分）で約６時間かか
る。また、ダミー付け法では、光ファイバ母材３の全体
重量が重くなり、ハンドリングが危険となる問題点があ
る。[Problems to be Solved by the Invention] However, in recent years, the size of the optical fiber preform 3 has been increasing to a large diameter of 45 to 70 mm, and in the dummy attaching method shown in FIG. There is a problem that formation requires a large amount of oxygen and hydrogen and time. For example, burner 2
It takes about 6 hours for a book (H 2 = 150 / min, O 2 = 75 / min). Further, the dummy attaching method has a problem that the entire weight of the optical fiber preform 3 becomes heavy and handling becomes dangerous.
本発明の目的は、経済的に且つ危険作業を回避して、
引き残しをほとんどなくすことができる光ファイバの製
造方法を提供することにある。The object of the present invention is to avoid economical and dangerous work,
An object of the present invention is to provide a method for manufacturing an optical fiber that can hardly leave behind.
［課題を解決するための手段］ 上記の目的を達成するための本発明の手段を説明する
と、本発明は線引き炉で光ファイバ母材を加熱しつつ線
引きして光ファイバを製造する光ファイバの製造方法に
おいて、円筒状で内径が前記光ファイバ母材より大きく
且つ上端には蓋部が設けられ該蓋部には前記光ファイバ
母材のサポート棒の外径より大きいサポート棒貫通兼ガ
ス流出口があけられている上部シール蓋と、円盤状で外
径が前記上部シール蓋の内径より小さく且つ中央に前記
サポート棒の外径より大きいサポート棒貫通兼ガス流出
口と該サポート棒貫通兼ガス流出口の周囲に開口されて
いる放射状ガス流出口とがあけられている下部シール蓋
とを、前記上部シール蓋の蓋部の下に前記下部シール蓋
を重ねた状態で、前記線引き炉の上方の前記光ファイバ
母材の上端部に被せて線引きを行うことを特徴とする。Means for Solving the Problems To explain the means of the present invention for achieving the above object, the present invention relates to an optical fiber for producing an optical fiber by drawing an optical fiber preform while heating the optical fiber preform in a drawing furnace. In the manufacturing method, a support rod penetrating and gas outlet having a cylindrical shape and an inner diameter larger than the optical fiber preform and having a lid provided at an upper end thereof is larger than an outer diameter of the support rod of the optical fiber preform. An upper seal lid which is opened, a disk-shaped support rod penetration and gas outlet, and a support rod penetration and gas flow which are smaller than the inner diameter of the upper seal lid and larger than the outer diameter of the support rod in the center. A radial gas outlet that is open around the outlet and a lower seal lid that is open, with the lower seal lid superimposed below the lid of the upper seal lid, and above the drawing furnace. Said It is characterized in that it is drawn over the upper end of the optical fiber preform.
［作用］ このように線引き炉の上部に突出した光ファイバ母材
の上端部に下部シール蓋と上部シール蓋を被せて線引き
すると、線引き炉の進行につれてサポート棒が光ファイ
バ母材挿入口を貫通する状態になったとき、上部シール
蓋が線引き炉の上に乗って該光ファイバ母材挿入口を塞
ぎ、代りに炉心管内のシールガスを下部シール蓋と上部
シール蓋の各サポート棒貫通兼ガス流出穴から流出させ
る。特に、円筒状の上部シール蓋と円盤状の下部シール
蓋とを用い、該下部シール蓋を上部シール蓋の蓋部の下
に重ねて使用すると、上部シール蓋が炉体の上に乗った
とき、該上部シール蓋の上部では蓋部のサポート棒貫通
兼ガス流出口が光ファイバ母材の上端テーパ部で塞が
れ、下部では炉体上部で塞がれ、一瞬該上部シール蓋内
が密閉状態になって炉内のシールガスの流れが変わるの
を、下部シール蓋のサポート棒貫通兼ガス流出口の周囲
の放射状ガス流出口が防ぐことになる。[Operation] When the lower seal lid and the upper seal lid are put on the upper end of the optical fiber preform protruding from the upper part of the drawing furnace as described above, the support rod penetrates the optical fiber preform insertion port as the drawing furnace proceeds. The upper seal lid rides on the drawing furnace to close the optical fiber preform insertion port, and instead, the sealing gas in the furnace tube passes through the support rods of the lower seal lid and the upper seal lid. Drain from outflow hole. In particular, when a cylindrical upper seal lid and a disc-shaped lower seal lid are used, and the lower seal lid is used under the lid of the upper seal lid, when the upper seal lid rides on the furnace body, In the upper part of the upper seal lid, the support rod penetration and gas outlet of the lid part are closed by the upper end taper part of the optical fiber preform, and in the lower part, the upper part of the furnace body is closed, and the inside of the upper seal lid is momentarily sealed. The radial gas outlet around the support rod penetration of the lower seal lid and the gas outlet prevents the flow of the seal gas in the furnace from changing to the state.
［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。Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
第１図及び第２図は、本発明の方法を実施する光ファ
イバ製造装置の一実施例を示したものである。本実施例
では、線引き炉１の上方に突出した光ファイバ母材３の
上端部に、上部シール蓋16と下部シール蓋17とを被せて
いる。上部シール蓋16は、円筒状で内径が光ファイバ母
材３より大きく且つ上端には蓋部16aが設けられ、該蓋
部16aには光ファイバ母材３のサポート棒14の外径より
大きいサポート棒貫通兼ガス流出口16bがあけられた構
造になっている。該上部シール蓋16の長さ（高さ）は、
光ファイバ母材３の上端テーパ部の軸心方向長さと同じ
か或いは約10〜50mm長めがよい。下部シール蓋17は、円
盤状で外径が上部シール蓋16の内径より小さく且つ中央
にサポート棒の外径より大きいサポート棒貫通兼ガス流
出口17aと、該サポート棒貫通兼ガス流出口17aの周囲に
開口されている放射状ガス流出口17bとがあけられた構
造になっていて、上部シール蓋16の蓋部16aの下に重ね
て使用される。FIG. 1 and FIG. 2 show an embodiment of an optical fiber manufacturing apparatus for carrying out the method of the present invention. In the present embodiment, an upper seal lid 16 and a lower seal lid 17 are placed on the upper end of the optical fiber preform 3 projecting above the drawing furnace 1. The upper seal lid 16 is cylindrical and has an inner diameter larger than that of the optical fiber preform 3 and is provided with a lid 16a at the upper end, and the lid 16a has a support larger than the outer diameter of the support rod 14 of the optical fiber preform 3. It has a structure in which a rod penetration and gas outlet 16b is opened. The length (height) of the upper seal lid 16 is
It is preferable that the length be the same as the axial center length of the upper end tapered portion of the optical fiber preform 3, or be longer by about 10 to 50 mm. The lower seal lid 17 has a disk-shaped outer diameter smaller than the inner diameter of the upper seal lid 16 and a centrally larger support rod penetration and gas outlet 17a larger than the outer diameter of the support rod, and a support rod penetration and gas outlet 17a. It has a structure in which a radial gas outlet 17b that is open to the periphery is opened, and is used under the lid 16a of the upper seal lid 16 so as to overlap.
このように光ファイバ母材３の上端部に上部シール蓋
16と下部シール蓋17とを被せて線引きを行うと、線引き
の進行につれてサポート棒14が光ファイバ母材挿入口10
を貫通する状態になったとき、上部シール蓋16が線引き
炉１の上に乗って光ファイバ母材挿入口10を塞ぎ、該光
ファイバ母材挿入口10からの空気の侵入を阻止できるよ
うになる。この状態で上部シール蓋16と下部シール蓋17
との各サポート棒貫通兼ガス流出口16b,17aのサポート
棒14との間のクリアランスは、適度な大きさであり、こ
れらサポート棒貫通兼ガス流出口16b,17aが炉心管６内
のシールガスの流出口となる。As described above, the upper seal lid is provided on the upper end of the optical fiber preform 3.
When the wire is drawn with the lower cover 16 and the lower seal lid 17 covered, the support rod 14 is moved into the optical fiber preform insertion port 10 as the drawing progresses.
The upper seal lid 16 rides on the drawing furnace 1 to close the optical fiber preform insertion port 10 so that air can be prevented from entering from the optical fiber preform insertion port 10. Become. In this state, the upper seal lid 16 and the lower seal lid 17
The clearance between each support rod penetrating and gas outlet 16b, 17a and the support rod 14 is moderate, and these support rod penetrating and gas outlets 16b, 17a are used for sealing gas in the core tube 6. Outlet.
従って、光ファイバ母材挿入口10からの空気の侵入を
防止しつつ、光ファイバ母材３の上部の線引きを行うこ
とができ、引き残りをほとんどなくすことができる。ま
た、上部シール蓋16の蓋部16aの下に下部シール蓋17を
重ねているので、上部シール蓋16が炉体５の上に乗った
とき、該上部シール蓋16の上部では蓋部16aのサポート
棒貫通兼ガス流出口16bが光ファイバ母材３の上端テー
パ部3aで塞がれ、下部では炉体５の上部の上部シール部
８で塞がれ、一瞬該上部シール蓋16内が密閉状態になっ
て炉心管６内のシールガスの流れが変わるのを、下部シ
ール蓋17のサポート棒貫通兼ガス流出口17aの周囲に設
けられた放射状ガス流出口17bによって防ぐことにな
る。Therefore, it is possible to draw the upper portion of the optical fiber preform 3 while preventing the intrusion of air from the optical fiber preform insertion port 10, and it is possible to almost eliminate the undrawn portion. In addition, since the lower seal lid 17 is placed under the lid 16a of the upper seal lid 16, when the upper seal lid 16 rides on the furnace body 5, the lid 16a The support rod penetration and gas outlet 16b is closed by the upper end taper portion 3a of the optical fiber preform 3, and the lower portion is closed by the upper seal portion 8 on the upper part of the furnace body 5, and the inside of the upper seal lid 16 is momentarily sealed. A change in the flow of the seal gas in the core tube 6 due to the state is prevented by the radial gas outlet 17b provided around the support rod penetration and gas outlet 17a of the lower seal lid 17.
前述した上部シール蓋16のサポート防貫通兼ガス流出
口16bとサポート棒14との間のクリアランスの断面積及
び下部シール蓋17の放射状ガス流出口17bの総断面積
は、光ファイバ母材挿入口10と光ファイバ母材３との間
のクリアランスの断面積にそれぞれ等しいことが好まし
い。The cross-sectional area of the clearance between the support anti-penetration / gas outlet 16b of the upper seal lid 16 and the support rod 14 and the total cross-sectional area of the radial gas outlet 17b of the lower seal lid 17 are the optical fiber preform insertion port. It is preferable that the cross-sectional area of the clearance between the optical fiber preform 3 and the optical fiber preform 3 is equal to each other.
なお、下部シール蓋17は１枚に限られず複数枚にして
もよい。The number of the lower seal lid 17 is not limited to one, but may be plural.
［発明の効果］ 以上説明したように本発明に係る光ファイバの製造方
法では、線引き炉の上部に突出した光ファイバ母材の上
端部に上部シール蓋と下部シール蓋を被せて線引きする
ので、線引きの進行につれてサポート棒が光ファイバ母
材挿入口を貫通する状態になったとき、上部シール蓋が
線引き炉の上に乗って該光ファイバ母材挿入口を塞ぎ、
代りに炉心管内のシールガスを該上部シール蓋と下部シ
ール蓋の各サポート棒貫通兼ガス流出口と下部シール蓋
の放射状ガス流出口とから流出させることができる。従
って、このようにして線引きを行うと、光ファイバ母材
の引き残りをほとんどなくして、経済的に線引きするこ
とができる。また、上部シール蓋の蓋部の下に下部シー
ル蓋を重ねているので、上部シール蓋が炉体の上に乗っ
たとき、該上部シール蓋の上部では蓋部のサポート棒貫
通兼ガス流出口が光ファイバ母材の上端テーパ部で塞が
れ、下部では炉体の上部の上部シール部で塞がれ、一瞬
該上部シール蓋内が密閉状態になって炉心管内のシール
ガスの流れが変わるのを、下部シール蓋のサポート棒貫
通兼ガス流出口の周囲に設けられた放射状ガス流出口で
防ぐことができる。かつまた、上部シール蓋は中空で軽
量であり、下部シールは円盤状で軽量なので、ハンドリ
ングが容易となり、且つ製作コストも安く、しかも繰り
返し利用でき、経済的に実施できる利点がある。[Effects of the Invention] As described above, in the method for manufacturing an optical fiber according to the present invention, since the upper seal lid and the lower seal lid are placed on the upper end of the optical fiber preform protruding from the upper part of the drawing furnace, drawing is performed. When the support rod penetrates the optical fiber preform insertion port as the drawing progresses, the upper seal lid rides on the drawing furnace and closes the optical fiber preform insertion port,
Instead, the seal gas in the core tube can be discharged from the support rod penetration and gas outlet of the upper seal lid and the lower seal lid and the radial gas outlet of the lower seal lid. Therefore, when the drawing is performed in this way, the drawing of the optical fiber preform is almost eliminated, and the drawing can be performed economically. In addition, since the lower seal lid is superimposed below the lid of the upper seal lid, when the upper seal lid rides on the furnace body, the support rod of the lid penetrates the gas outlet at the top of the upper seal lid. Is closed by the upper end taper portion of the optical fiber preform, and the lower portion is closed by the upper seal portion at the upper part of the furnace body, the inside of the upper seal lid is momentarily sealed, and the flow of the seal gas in the furnace tube changes. This can be prevented by a radial gas outlet provided around the support rod penetration and gas outlet of the lower seal lid. Further, since the upper seal lid is hollow and lightweight, and the lower seal is disc-shaped and lightweight, there is an advantage that the handling is easy, the production cost is low, and it can be repeatedly used and can be implemented economically.
第１図は本発明の方法を実施する光ファイバ製造装置の
一実施例における第２図のＡ−Ａ線の箇所での要部縦断
面図、第２図は本発明で用いる下部シール蓋の一例を示
す平面図、第３図は従来の光ファイバ製造装置の縦断面
図、第４図及び第５図は従来の光ファイバ母材の２種の
例を示す側面図である。 １……線引き炉、２……光ファイバ、３……光ファイバ
母材、５……炉体、６……炉心管、７……ヒータ、８…
…上部シール、９……下部シール、10……光ファイバ母
材挿入口、11……上部ガス注入口、12……下部ガス注入
口、13……中部ガス注入口、14……サポート棒、15……
ダミー石英棒、16……上部シール蓋、16a……蓋部、16b
……サポート棒貫通兼ガス流出口、17……下部シール
蓋、17a……サポート棒貫通兼ガス流出口、17b……放射
状ガス流出口。FIG. 1 is a longitudinal sectional view of an essential part taken along line AA of FIG. 2 in one embodiment of an optical fiber manufacturing apparatus for carrying out the method of the present invention, and FIG. FIG. 3 is a plan view showing one example, FIG. 3 is a longitudinal sectional view of a conventional optical fiber manufacturing apparatus, and FIGS. 4 and 5 are side views showing two examples of a conventional optical fiber preform. DESCRIPTION OF SYMBOLS 1 ... Drawing furnace, 2 ... Optical fiber, 3 ... Optical fiber preform, 5 ... Furnace body, 6 ... Furnace tube, 7 ... Heater, 8 ...
... upper seal, 9 ... lower seal, 10 ... optical fiber preform insertion port, 11 ... upper gas inlet, 12 ... lower gas inlet, 13 ... middle gas inlet, 14 ... support rod, 15 ……
Dummy quartz rod, 16 ... top seal lid, 16a ... lid, 16b
... Support rod penetration and gas outlet, 17 ... Lower seal lid, 17a ... Support rod penetration and gas outlet, 17b ... Radial gas outlet.
Claims (1)
引きして光ファイバを製造する光ファイバの製造方法に
おいて、円筒状で内径が前記光ファイバ母材より大きく
且つ上端には蓋部が設けられ該蓋部には前記光ファイバ
母材のサポート棒の外径より大きいサポート棒貫通兼ガ
ス流出口があけられている上部シール蓋と、円盤状で外
径が前記上部シール蓋の内径より小さく且つ中央に前記
サポート棒の外径より大きいサポート棒貫通兼ガス流出
口と該サポート棒貫通兼ガス流出口の周囲に開口されて
いる放射状ガス流出口とがあけられている下部シール蓋
とを、前記上部シール蓋の蓋部の下に前記下部シール蓋
を重ねた状態で、前記線引き炉の上方の前記光ファイバ
母材の上端部に被せて線引きを行うことを特徴とする光
ファイバの製造方法。1. An optical fiber manufacturing method for manufacturing an optical fiber by drawing an optical fiber preform while heating the optical fiber preform in a drawing furnace, the method comprising the steps of: An upper seal lid provided with a support rod penetrating and gas outlet larger than the outer diameter of the support rod of the optical fiber preform is provided on the lid, and a disk-shaped outer diameter is larger than the inner diameter of the upper seal lid. A lower seal lid having a small and centrally opened support rod penetration and gas outlet which is larger than the outer diameter of the support rod and a radial gas outlet opened around the support rod penetration and gas outlet; Producing the optical fiber, wherein the lower seal lid is superimposed below the lid of the upper seal lid, and the upper end of the optical fiber preform above the drawing furnace is drawn to perform drawing. One .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26596089A JP2618498B2 (en) | 1989-10-12 | 1989-10-12 | Optical fiber manufacturing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26596089A JP2618498B2 (en) | 1989-10-12 | 1989-10-12 | Optical fiber manufacturing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03126635A JPH03126635A (en) | 1991-05-29 |
| JP2618498B2 true JP2618498B2 (en) | 1997-06-11 |
Family
ID=17424446
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP26596089A Expired - Lifetime JP2618498B2 (en) | 1989-10-12 | 1989-10-12 | Optical fiber manufacturing method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2618498B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6381990B1 (en) * | 1999-02-26 | 2002-05-07 | Corning Incorporated | Draw furnace sealing assembly and method |
-
1989
- 1989-10-12 JP JP26596089A patent/JP2618498B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH03126635A (en) | 1991-05-29 |
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