JPH04254432A - Method and device for drawing optical fiber - Google Patents
Method and device for drawing optical fiberInfo
- Publication number
- JPH04254432A JPH04254432A JP1648491A JP1648491A JPH04254432A JP H04254432 A JPH04254432 A JP H04254432A JP 1648491 A JP1648491 A JP 1648491A JP 1648491 A JP1648491 A JP 1648491A JP H04254432 A JPH04254432 A JP H04254432A
- Authority
- JP
- Japan
- Prior art keywords
- optical fiber
- furnace body
- pressure
- furnace
- carbon heater
- 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
- 239000013307 optical fiber Substances 0.000 title claims abstract description 54
- 238000000034 method Methods 0.000 title claims description 12
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 37
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 30
- 238000012681 fiber drawing Methods 0.000 claims abstract description 17
- 238000007789 sealing Methods 0.000 claims abstract description 7
- 238000010438 heat treatment Methods 0.000 claims description 3
- 239000000835 fiber Substances 0.000 claims description 2
- 239000000498 cooling water Substances 0.000 abstract description 5
- 239000011810 insulating material Substances 0.000 abstract description 5
- 239000000463 material Substances 0.000 abstract description 4
- 239000007789 gas Substances 0.000 description 17
- 230000000694 effects Effects 0.000 description 2
- 238000010926 purge Methods 0.000 description 2
- 238000012216 screening Methods 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 239000012774 insulation material Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
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
-
- 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
- C03B2205/62—Heating means for drawing
- C03B2205/63—Ohmic resistance heaters, e.g. carbon or graphite resistance heaters
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は、炉体内に挿入した光フ
ァイバ母材の下部をカーボンヒータで加熱し、該光ファ
イバ母材の加熱溶融部分から光ファイバを線引きする光
ファイバの線引き方法及び装置に関するものである。[Industrial Application Field] The present invention relates to an optical fiber drawing method in which the lower part of an optical fiber preform inserted into a furnace is heated with a carbon heater, and an optical fiber is drawn from the heated and melted portion of the optical fiber preform. It is related to the device.
【０００２】0002
【従来の技術】従来の光ファイバの線引き装置は、図２
に示すように、ＳＵＳ等の金属製の炉体１内の中心にカ
ーボン製の炉心管２が配置され、該炉心管１の外周の炉
体１内にカーボンヒータ３が配置され、該カーボンヒー
タ３の周囲の炉体１内にカーボン製の断熱材４が配置さ
れ、炉体１内で炉心管２と断熱材４の下にはカーボン製
のベース５が配置された構造となっていた。炉体１は二
重構造になっていて、冷却水入口６から冷却水を供給し
、該炉体１を冷却した冷却水を冷却水出口７から排出す
ることにより炉体１の冷却を行っていた。炉体１の上部
には、シールガス入口８ａが設けられ、ここからＮ２
，Ａｒ，Ｈｅ等の不活性ガスをシールガスとして炉体１
内に供給するようになっている。炉体１の下部には、シ
ールガス出口８ｂが設けられている。炉体１内に入った
シールガスは、カーボンヒータ３や断熱材４の間等を伝
わってベース５の下側に回り込み、アッパーフローとな
って炉心管２の下部から上部へ上昇するようになってい
る。[Prior Art] A conventional optical fiber drawing device is shown in FIG.
As shown in the figure, a carbon furnace core tube 2 is placed at the center of a metal furnace body 1 such as SUS, and a carbon heater 3 is placed inside the furnace body 1 on the outer periphery of the furnace core tube 1. A carbon heat insulating material 4 is disposed in the furnace body 1 around the furnace body 3, and a carbon base 5 is disposed within the furnace body 1 under the furnace core tube 2 and the heat insulating material 4. The furnace body 1 has a double structure, and the furnace body 1 is cooled by supplying cooling water from a cooling water inlet 6 and discharging the cooling water that has cooled the furnace body 1 from a cooling water outlet 7. Ta. A seal gas inlet 8a is provided in the upper part of the furnace body 1, and N2 is supplied from here.
, Ar, He, etc. as a seal gas in the furnace body 1.
It is designed to be supplied internally. A seal gas outlet 8b is provided at the bottom of the furnace body 1. The seal gas that has entered the furnace body 1 travels between the carbon heater 3 and the heat insulating material 4, wraps around the bottom of the base 5, becomes an upper flow, and rises from the bottom of the furnace tube 2 to the top. ing.
【０００３】炉心管２内には光ファイバ母材９が挿入さ
れ、カーボンヒータ３で加熱される該光ファイバ母材９
の下部から光ファイバ１０が線引きされる。[0003] An optical fiber preform 9 is inserted into the reactor core tube 2, and the optical fiber preform 9 is heated by a carbon heater 3.
An optical fiber 10 is drawn from the bottom of the .
【０００４】この場合、カーボンヒータ３は、通常２０
００〜 ２３００℃位に加熱される。該カーボンヒータ
３の通電前に炉体１内の空気をパージするため、約５〜
６ｈｒシールガスを該炉体１内に供給する。該シールガ
スの供給量は、炉体１のサイズにもよるが、一例を示せ
ば３０〜５０ ｌ／分である。In this case, the carbon heater 3 usually has 20
It is heated to about 00 to 2300℃. In order to purge the air inside the furnace body 1 before energizing the carbon heater 3, approximately
6 hours of seal gas is supplied into the furnace body 1. The supply amount of the seal gas depends on the size of the furnace body 1, but for example, it is 30 to 50 l/min.
【０００５】[0005]
【発明が解決しようとする課題】このように、シールガ
スを一定時間、一定量炉体１内に供給してもカーボンヒ
ータ３は多孔質構造なので、その孔内にある酸素との置
換は十分とはいいがたい。また、該カーボンヒータ３の
表面に物理的に吸着している水分もあり、これらを完全
に除去することは困難である。[Problems to be Solved by the Invention] As described above, even if a certain amount of sealing gas is supplied into the furnace body 1 for a certain period of time, since the carbon heater 3 has a porous structure, the replacement with oxygen in the pores is sufficient. It's hard to say. In addition, some moisture is physically adsorbed on the surface of the carbon heater 3, and it is difficult to completely remove this moisture.
【０００６】このような状態から、カーボンヒータ３に
通電し、昇温を開始すると、これら水分，空気がカーボ
ンと反応し、カーボン部品を損傷することになる。一応
、カーボンヒータ３と断熱材４が存在する部分と炉心管
２の内側との間は仕切られているが、一部のシールガス
がカーボンヒータ３側から炉心管２の内側へ流れ込む。
この時、カーボンの損傷屑や微粉が炉心管２内に流れ込
み、滞留する。If the carbon heater 3 is energized to start raising the temperature in such a state, the moisture and air will react with the carbon and damage the carbon parts. Although the portion where the carbon heater 3 and the heat insulating material 4 are present and the inside of the furnace tube 2 are partitioned off, some seal gas flows into the inside of the furnace tube 2 from the carbon heater 3 side. At this time, damaged carbon debris and fine powder flow into the core tube 2 and remain there.
【０００７】これらの微粒子群が光ファイバ母材９から
線引きした光ファイバ１０の表面に付着し、該光ファイ
バ１０の強度不足の一因となっている。[0007] These fine particles adhere to the surface of the optical fiber 10 drawn from the optical fiber preform 9, contributing to the lack of strength of the optical fiber 10.
【０００８】本発明の目的は、炉体内のカーボン部品に
残留した空気を十分に除去することができる光ファイバ
の線引き方法及び装置を提供することにある。[0008] An object of the present invention is to provide an optical fiber drawing method and apparatus that can sufficiently remove air remaining in carbon parts within a furnace body.
【０００９】[0009]
【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、次の通りである。[Means for Solving the Problems] The means of the present invention for achieving the above object will be explained as follows.
【００１０】請求項１に記載の発明は、炉体内の中心に
炉心管が配置され、前記炉心管の外周の前記炉体内にカ
ーボンヒータが配置された光ファイバ線引き炉を用い、
前記炉体内に挿入した光ファイバ母材の下部を前記カー
ボンヒータで加熱し、前記光ファイバ母材の加熱溶融部
分から光ファイバを線引きする光ファイバの線引き方法
において、前記炉体内を減圧した後、該炉体内にシール
ガスを供給した状態で前記カーボンヒータを加熱し、前
記光ファイバの線引きを開始することを特徴とする。[0010] The invention according to claim 1 uses an optical fiber drawing furnace in which a core tube is disposed at the center of the furnace body, and a carbon heater is disposed within the furnace body at the outer periphery of the core tube,
In an optical fiber drawing method in which a lower part of an optical fiber preform inserted into the furnace body is heated by the carbon heater and an optical fiber is drawn from the heated and melted portion of the optical fiber preform, after reducing the pressure inside the furnace body, The method is characterized in that drawing of the optical fiber is started by heating the carbon heater while supplying seal gas into the furnace body.
【００１１】請求項２に記載の発明は、炉体内の中心に
炉心管が配置され、前記炉心管の外周の前記炉体内にカ
ーボンヒータが配置され、前記炉体内に挿入された光フ
ァイバ母材の下部を前記カーボンヒータで加熱し、前記
光ファイバ母材の加熱溶融部分から光ファイバを線引き
する光ファイバの線引き装置において、前記炉体にはそ
の内部の減圧をする減圧装置が接続されていることを特
徴とする。[0011] In the invention as set forth in claim 2, a furnace core tube is disposed at the center of the furnace body, a carbon heater is disposed inside the furnace body on the outer periphery of the furnace core tube, and an optical fiber preform inserted into the furnace body. In an optical fiber drawing device that heats a lower part of the furnace body with the carbon heater and draws an optical fiber from the heated and melted portion of the optical fiber base material, a pressure reducing device that reduces the pressure inside the furnace body is connected to the furnace body. It is characterized by
【００１２】0012
【作用】請求項１に示すように、炉体内を減圧すると、
炉体内のカーボン部品内に残留した空気を十分に取除く
ことができる。[Operation] As shown in claim 1, when the pressure inside the furnace body is reduced,
Air remaining in the carbon parts inside the furnace body can be sufficiently removed.
【００１３】請求項２に示すように、炉体にその内部の
減圧をする減圧装置を接続しておくと、炉体内の減圧作
業を容易に行うことができる。[0013] As shown in claim 2, when a pressure reducing device for reducing the pressure inside the furnace body is connected to the furnace body, the pressure reduction operation inside the furnace body can be easily performed.
【００１４】[0014]
【実施例】以下、本発明の実施例を図１を参照して詳細
に説明する。なお、前述した図２と対応する部分には、
同一符号を付けて示している。Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to FIG. In addition, in the part corresponding to the above-mentioned FIG. 2,
They are shown with the same reference numerals.
【００１５】図示のように、本実施例の光ファイバの線
引き装置においては、炉体１に吸引パイプ１１を介して
真空ポンプ１２と圧力計１３とが接続されている。該真
空ポンプ１２には、コントローラ１４が接続されている
。これら吸引パイプ１１，真空ポンプ１２，圧力計１３
，コントローラ１４により、炉体１内を減圧をする減圧
装置１５が構成されている。As shown in the figure, in the optical fiber drawing apparatus of this embodiment, a vacuum pump 12 and a pressure gauge 13 are connected to a furnace body 1 via a suction pipe 11. A controller 14 is connected to the vacuum pump 12. These suction pipe 11, vacuum pump 12, pressure gauge 13
, controller 14 constitute a pressure reducing device 15 that reduces the pressure inside the furnace body 1.
【００１６】次に、このような減圧装置１５を用いた本
実施例の光ファイバの線引き方法について説明する。Next, a method of drawing an optical fiber according to this embodiment using such a pressure reducing device 15 will be explained.
【００１７】（１）真空ポンプ１２を作動させ、炉体１
内を−７６０ ｍｍＨ２ Ｏに減圧する。(1) Operate the vacuum pump 12 and remove the furnace body 1.
The inside pressure is reduced to -760 mmH2O.
【００１８】（２）真空引きを停止し、炉体１内にＡｒ
ガスよりなるシールガスを注入する。
（３）真空ポンプ１２を作動させ、炉体１内を−７６０
ｍｍＨ２ Ｏに減圧する。(2) Stop evacuation and fill Ar in the furnace body 1.
Inject seal gas consisting of gas. (3) Operate the vacuum pump 12 to reduce the inside of the furnace body 1 to -760
Vacuum to mmH2O.
【００１９】（４）真空引きを停止し、炉体１内にＡｒ
ガスよりなるシールガスを注入する。以上の操作を設定
回数繰り返す。このような操作は、図示しない自動弁の
開閉により行う。また、減圧の際には、光ファイバ母材
９や光ファイバ１０の出入り口に栓をする。(4) Stop evacuation and fill Ar in the furnace body 1.
Inject seal gas consisting of gas. Repeat the above operation a set number of times. Such operations are performed by opening and closing an automatic valve (not shown). Furthermore, when reducing the pressure, the entrances and exits of the optical fiber preform 9 and the optical fiber 10 are plugged.
【００２０】このようにすることで、昇温前の炉体１内
の空気の除去を完全なものとすることができる。この結
果、昇温前の約５〜６ｈｒにわたるパージ時間が不要に
なった。当然、使用ガス量も格段に低減できた。また、
カーボン部品の損傷も低減でき、特にカーボンヒータ３
の寿命が１０日間から約４０日に伸びた。更に、光ファ
イバ１０の強度も、平均スクリーニング長（スクリーニ
ング荷重１Ｋｇ）が約２５Ｋｍから約３５Ｋｇへ伸びた
（各々の総線引き長は ４００Ｋｍずつ）。[0020] By doing so, the air in the furnace body 1 before the temperature rise can be completely removed. As a result, approximately 5-6 hr of purge time was not required before heating. Naturally, the amount of gas used was also significantly reduced. Also,
Damage to carbon parts can also be reduced, especially carbon heater 3.
The lifespan of the human body has increased from 10 days to about 40 days. Furthermore, the strength of the optical fiber 10 has been increased from about 25 Km to about 35 Kg in average screening length (screening load 1 Kg) (total drawing length of each fiber is 400 Km).
【００２１】以上のように本発明の線引き方法によれば
、ランニングコスト及び光ファイバ品質の両方で優れた
効果を得られることを確認することができた。As described above, it has been confirmed that the drawing method of the present invention provides excellent effects in terms of both running costs and optical fiber quality.
【００２２】[0022]
【発明の効果】以上説明したように本発明に係る光ファ
イバの線引き方法及び装置によれば、次のような優れた
効果を得ることができる。As explained above, according to the optical fiber drawing method and apparatus according to the present invention, the following excellent effects can be obtained.
【００２３】請求項１に記載の光ファイバの線引き方法
においては、炉体内を減圧した後、該炉体内にシールガ
スを供給した状態でカーボンヒータを加熱し、光ファイ
バの線引きを開始するので、炉体内の減圧により、該炉
体内のカーボン部品内に残留した空気を十分に取除くこ
とができる。従って、本発明の光ファイバの線引き方法
によれば、炉体内のカーボン部品の損傷を防止すること
ができる。In the optical fiber drawing method according to claim 1, after reducing the pressure inside the furnace, the carbon heater is heated while sealing gas is supplied into the furnace, and drawing of the optical fiber is started. By reducing the pressure inside the furnace body, the air remaining in the carbon parts within the furnace body can be sufficiently removed. Therefore, according to the optical fiber drawing method of the present invention, damage to the carbon parts in the furnace can be prevented.
【００２４】請求項２に記載の光ファイバの線引き装置
においては、炉体にその内部の減圧をする減圧装置を接
続したので、炉体内の減圧作業を容易に行うことができ
る。In the optical fiber drawing apparatus according to the second aspect of the present invention, since a pressure reducing device for reducing the pressure inside the furnace body is connected to the furnace body, the pressure reduction operation inside the furnace body can be easily performed.
【図１】本発明に係る光ファイバの線引き装置の一実施
例を示す縦断面図である。FIG. 1 is a longitudinal sectional view showing an embodiment of an optical fiber drawing apparatus according to the present invention.
【図２】従来の光ファイバの線引き装置の一実施例を示
す縦断面図である。FIG. 2 is a longitudinal sectional view showing an embodiment of a conventional optical fiber drawing apparatus.
１ 炉体 ２ 炉心管 ３ カーボンヒータ ４ 断熱材 ５ ベース ８ａ シールガス入口 ８ｂ シールガス出口 ９ 光ファイバ母材 １０ 光ファイバ １１ 吸引パイプ １２ 真空ポンプ １３ 圧力計 １４ コントローラ １５ 減圧装置 1 Furnace body 2 Furnace core tube 3 Carbon heater 4 Insulation material 5 Base 8a Seal gas inlet 8b Seal gas outlet 9 Optical fiber base material 10 Optical fiber 11 Suction pipe 12 Vacuum pump 13 Pressure gauge 14 Controller 15 Pressure reduction device
Claims (2)
記炉心管の外周の前記炉体内にカーボンヒータが配置さ
れた光ファイバ線引き炉を用い、前記炉体内に挿入した
光ファイバ母材の下部を前記カーボンヒータで加熱し、
前記光ファイバ母材の加熱溶融部分から光ファイバを線
引きする光ファイバの線引き方法において、前記炉体内
を減圧した後、該炉体内にシールガスを供給した状態で
前記カーボンヒータを加熱し、前記光ファイバの線引き
を開始することを特徴とする光ファイバの線引き方法。1. Using an optical fiber drawing furnace in which a core tube is disposed at the center of the furnace body, and a carbon heater is disposed inside the furnace body on the outer periphery of the core tube, an optical fiber preform inserted into the furnace body is drawn. heating the lower part with the carbon heater,
In the optical fiber drawing method of drawing an optical fiber from a heated and melted portion of the optical fiber preform, after reducing the pressure inside the furnace body, the carbon heater is heated while sealing gas is supplied into the furnace body, and the 1. A method for drawing an optical fiber, comprising starting drawing of the fiber.
記炉心管の外周の前記炉体内にカーボンヒータが配置さ
れ、前記炉体内に挿入された光ファイバ母材の下部を前
記カーボンヒータで加熱し、前記光ファイバ母材の加熱
溶融部分から光ファイバを線引きする光ファイバの線引
き装置において、前記炉体にはその内部の減圧をする減
圧装置が接続されていることを特徴とする光ファイバの
線引き装置。2. A furnace tube is disposed at the center of the furnace body, a carbon heater is disposed inside the furnace body at the outer periphery of the furnace tube, and the lower part of the optical fiber preform inserted into the furnace body is heated by the carbon heater. An optical fiber drawing device that heats and draws an optical fiber from a heated and molten portion of the optical fiber preform, characterized in that the furnace body is connected to a pressure reducing device that reduces the pressure inside the furnace body. line drawing device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1648491A JPH04254432A (en) | 1991-02-07 | 1991-02-07 | Method and device for drawing optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1648491A JPH04254432A (en) | 1991-02-07 | 1991-02-07 | Method and device for drawing optical fiber |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04254432A true JPH04254432A (en) | 1992-09-09 |
Family
ID=11917562
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1648491A Pending JPH04254432A (en) | 1991-02-07 | 1991-02-07 | Method and device for drawing optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04254432A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102775058A (en) * | 2012-07-09 | 2012-11-14 | 西安思翰光电科技有限公司 | High-precision resistance type heating furnace for medium-low-temperature optical fiber drawing tower |
| TWI393851B (en) * | 2008-05-16 | 2013-04-21 | Zhen Ding Technology Co Ltd | Vaccum oven |
| CN103771697A (en) * | 2012-10-22 | 2014-05-07 | 浙江富通光纤技术有限公司 | Sintering method and apparatus for large-size optical fiber preform loose body |
| CN104503509A (en) * | 2014-12-04 | 2015-04-08 | 中天科技光纤有限公司 | Induction furnace water temperature constant automatic control system and method |
-
1991
- 1991-02-07 JP JP1648491A patent/JPH04254432A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI393851B (en) * | 2008-05-16 | 2013-04-21 | Zhen Ding Technology Co Ltd | Vaccum oven |
| CN102775058A (en) * | 2012-07-09 | 2012-11-14 | 西安思翰光电科技有限公司 | High-precision resistance type heating furnace for medium-low-temperature optical fiber drawing tower |
| CN103771697A (en) * | 2012-10-22 | 2014-05-07 | 浙江富通光纤技术有限公司 | Sintering method and apparatus for large-size optical fiber preform loose body |
| CN104503509A (en) * | 2014-12-04 | 2015-04-08 | 中天科技光纤有限公司 | Induction furnace water temperature constant automatic control system and method |
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