JPH04193732A - Production of optical fiber base material - Google Patents
Production of optical fiber base materialInfo
- Publication number
- JPH04193732A JPH04193732A JP32163690A JP32163690A JPH04193732A JP H04193732 A JPH04193732 A JP H04193732A JP 32163690 A JP32163690 A JP 32163690A JP 32163690 A JP32163690 A JP 32163690A JP H04193732 A JPH04193732 A JP H04193732A
- Authority
- JP
- Japan
- Prior art keywords
- optical fiber
- base material
- temp
- fiber base
- leading
- 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.)
- Granted
Links
- 239000013307 optical fiber Substances 0.000 title claims abstract description 34
- 238000004519 manufacturing process Methods 0.000 title claims description 9
- 239000000463 material Substances 0.000 title abstract description 21
- 238000000034 method Methods 0.000 claims description 19
- 238000010438 heat treatment Methods 0.000 claims description 4
- 230000000694 effects Effects 0.000 description 5
- 239000011521 glass Substances 0.000 description 5
- 238000000926 separation method Methods 0.000 description 5
- 238000005491 wire drawing Methods 0.000 description 3
- 230000002411 adverse Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000000428 dust Substances 0.000 description 2
- 238000007524 flame polishing Methods 0.000 description 2
- 239000010453 quartz Substances 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 206010047571 Visual impairment Diseases 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 208000029257 vision disease Diseases 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
- 230000004393 visual impairment Effects 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
- C03B37/012—Manufacture of preforms for drawing fibres or filaments
- C03B37/014—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD]
- C03B37/01466—Means for changing or stabilising the diameter or form of tubes or rods
-
- 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
- C03B37/012—Manufacture of preforms for drawing fibres or filaments
- C03B37/01205—Manufacture of preforms for drawing fibres or filaments starting from tubes, rods, fibres or filaments
- C03B37/01225—Means for changing or stabilising the shape, e.g. diameter, of tubes or rods in general, e.g. collapsing
- C03B37/0124—Means for reducing the diameter of rods or tubes by drawing, e.g. for preform draw-down
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
Abstract
Description
本発明は、光ファイバ母材を線引き工程に送る前に行う
前処理において、切離時の張力を一定値にして制御する
光ファイバ母材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 preform in which the tension at the time of cutting is controlled to a constant value during pretreatment performed before the optical fiber preform is sent to a drawing process.
従来、光ファイバの製造にあったでは、先ず、始めに光
ファイバ母材を作り、この母材を線引きし、細線化（フ
ァイバ化）して製造している。
この線引きに際しては、その前処理として、■ＡＤ法や
外付は法などにより得られる光ファイバ母材の一端を、
切離し、口出し加工し、火炎研磨など行う必要があり、
従来、例えば第２図に示した如き装置により行っている
。
例えば縦型のガラス製旋盤１の上下部のフレーム２．３
間に各チャック４．５を介して、光ファイバ母材（石英
ロンド）６を把持させ、当該光ファイバ母材６を回転さ
せつつ、旋盤１例のトラバース機構８により上下動され
る酸水素バーナ７から、火炎を吹き付け、光ファイバ母
材６の下端付近を加熱して先端を切り離し、口出し加工
を行っている。
実際には、光ファイバ母材６の下端が加熱により軟化し
たところで、例えば上記旋盤１の下部フレーム３を矢印
入方向に押し下げて切り・離し、同時に線引き装置にセ
ットできるように細い先端形状に口出し加工している。
従来、この切り離しの下部フレーム３の移動は、人力に
よっていた。つまり、作業者が、切り離しのタイミング
を見て、操作ハンドルを回転させ、ギヤなどを介して、
下部フレーム３を移動させていた。Conventionally, in the production of optical fibers, an optical fiber preform is first produced, and this preform is drawn and thinned (fiberized). When drawing this wire, as a pretreatment, one end of the optical fiber base material obtained by the AD method or the external method is
It is necessary to perform cutting, cutting, flame polishing, etc.
Conventionally, this has been carried out using an apparatus as shown in FIG. 2, for example. For example, the upper and lower frames 2.3 of a vertical glass lathe 1
An oxyhydrogen burner is moved up and down by a traverse mechanism 8 of an example of a lathe, while an optical fiber base material (quartz rond) 6 is gripped through each chuck 4.5 in between, and the optical fiber base material 6 is rotated. From step 7, flame is blown to heat the vicinity of the lower end of the optical fiber preform 6, and the tip is cut off to perform a lead-out process. In reality, once the lower end of the optical fiber preform 6 has been softened by heating, the lower frame 3 of the lathe 1 is pressed down in the direction of the arrow to cut it and separate it, and at the same time, the tip is drawn into a thin tip shape so that it can be set in a wire drawing device. It is being processed. Conventionally, this separation of the lower frame 3 has been carried out manually. In other words, the operator sees the timing of separation, rotates the operating handle, and uses gears etc.
The lower frame 3 was being moved.
ところが、このように切り離しの下部フレーム３の移動
を人力に頼る場合、作業者には、下部フレーム３が最適
スピードで移動するよう細心の注意が必要とされる。
特に、作業者が、母材の表面色や形状などを見て切り離
しのタイミングを判断しながら、操作ハンドルを回転さ
せ、その張力が大き過ぎないようにするには、大きな負
担が掛かる。
例えば、下部フレーム３の移動速度が大き過ぎると、光
ファイバ母材の下部切離部が破損したり、母材上部に大
きな力が加わって、ダミーガラスが割れたり、あるいは
上部チャック２から抜は落ちたりする恐れがあった。
また、切離時の下部フレーム３の移動が一定に行われな
いと、切り離した後の先端形状にバラツキが生じ、線引
き装置にセットする際に必要な良好なｌ］出しが得られ
ないという問題が生しる。
このハラツギは、同一作業者が行っても、その発生はあ
る程度避けられないか、作業者が異なると、個人差が大
きく影響して、さらに顕著となる傾向がある。
また、この作業を、さらに困難にさせるものとて、この
作業環境は、酸水素バーナマの近傍で、しかも、高温、
高輝度を伴う環境であるごとも挙げられる。この目視作
業の場合、視覚への悪影響も懸念される。
本発明は、このような従来の実情に鑑みてなされたもの
である。However, when moving the lower frame 3 for separation depends on human power, the operator must be extremely careful to move the lower frame 3 at the optimum speed. In particular, it is a heavy burden for the operator to rotate the operating handle while judging the timing of separation by looking at the surface color and shape of the base material, and to ensure that the tension is not too large. For example, if the moving speed of the lower frame 3 is too high, the lower part of the optical fiber base material may be damaged, the dummy glass may break due to a large force being applied to the upper part of the base material, or the dummy glass may not be pulled out from the upper chuck 2. There was a risk of falling. Additionally, if the movement of the lower frame 3 during cutting is not constant, there will be variations in the shape of the tip after cutting, and there is a problem in that good l] required when setting it in the wire drawing device cannot be obtained. is born. Even if the same worker performs this problem, its occurrence is unavoidable to some extent, or if the worker is different, it tends to become more noticeable due to individual differences. What makes this work even more difficult is that the work environment is close to an oxyhydrogen burnama, and there is a high temperature.
Another example is the environment with high brightness. In the case of this visual work, there is also concern that it may have an adverse effect on vision. The present invention has been made in view of such conventional circumstances.
か＼る本発明の特徴とする点は、線引き工程前の光ファ
イバ母材の両端を把持して、該光ファイバ母材の下端付
近をバーナの火炎で加熱して切り離し、口出し加工を行
う工程において、前記光ファイバ母材の切離時の張力を
ある一定値に制御する光ファイバ母材の製造方法にある
。The feature of the present invention is the step of gripping both ends of the optical fiber preform before the drawing process, heating the vicinity of the lower end of the optical fiber preform with the flame of a burner, and cutting it off to perform the drawing process. In the present invention, there is provided a method for manufacturing an optical fiber preform in which the tension at the time of cutting the optical fiber preform is controlled to a certain constant value.
この方法では、切離時の張力をある一定値に制御するた
め、常に母材の切り離しがスムーズに行われ、一定形状
の先端形状、すなわち口出しが得られる。In this method, the tension at the time of cutting is controlled to a certain constant value, so that the base material is always separated smoothly and a constant shape of the tip, that is, a tip is obtained.
第１図は本発明に係る光ファイバ母材の製造方法の一実
施例を示したものである。
同図の装置系も、−に述した第２図の装置系とほぼ同様
であるが、本装置系では、光ファイバ母材の切離時の張
力をある一定値に制御する、下部フレーム３の移動機構
１０が設けである。
この移動機構１０の構成としては、特に限定されないが
、例えば２個のコロ２１，２１間に張設されたヘルｌ−
（チェーンも可）２２に下部フレーム３を固着する一方
、下方のコロ２２に駆動モーフ２３を連繋させてなる。
したがって、この駆動モータ２３を駆動させれば、常に
一定の張力（例えば、１．５〜２．０Ｋｇ／ｃｍ２程度
の張力）をもって、下部フレーム３を移動させることが
できる。
一方、好ましい例として、本装置系には、光ファイバ母
材（石英ロンド）６の表面温度を検出する温度センサＩ
Ｉを設け、これを外部のコント１コーラ（コンピュータ
などを含む制御部）１２と接続すると共に、このコンＩ
・ローラ１２には、ＣＲＴ、液晶テスプレなどのモニタ
１３を接続し、また、このコントローラ１２からは、上
記移動機構１０と、トラバース機構８、酸水素バーナ７
の制御信号が出力されるようになっている。
上記温度センサ１１としては、例えば温度センサ内蔵の
小型ＴＶカメラなどが使用でき、このカメラにより、切
り離そうとする光ファイバ母材６の表面画像を写し出す
と同時に、その表面温度も測定検出することができる。
しかして、本発明では、上記カメラによる、画像情報と
温度情報を外部のコントローラ１２に入力し、予め当該
コントローラ１２に設定しておいた切離し最適温度との
比較を行い、実測温度が一致したとき、最適タイミング
で移動機構】Ｏを駆動させ、下部フレーム３を一定の張
力により下降６一
させて光ファイバ母材６の下端を切り離し、その後、光
ファイバ母材６下端の口出し加工を行い、これが完了し
たら、トラバース機構８により酸水素バーナ７を所定の
位置に退避させる。
これにより、切り離しはスムーズに行われ、良好な口出
し形状がバラツキなく得られる。
また、上記コントローラ１２に接続されたモニタ１３に
より、作業者も、直接光ファイバ母材６表面の加熱状態
を見ることができる。
なお、上記実施例では、下部フレーム３の移動機構１０
をコントローラ１２により制御した例であったが、本発
明は、これに限定されず、単なる移動機構１０の駆動モ
ータ２３を正逆転させるスイッチのみでＩＩＪ ？卸す
ることもできる。
また、上記温度センサ内蔵のカメラでは、温度検出の他
に、母材表面に付着した塵埃の検出も可能であり、この
塵埃の検出により火炎研磨を行うことができる。さらに
、温度センサを撮像機構（カメラ）のない放射温度計と
し、その設置位置も光ファイバ母材の下端（例えば下部
フレーム３の下方）としたりすることも可能である。
さらに、上記実施例では、縦型のガラス製旋盤１を使用
した場合であったが、本発明は、これに限定されず、横
型のガラス製旋盤を用いる場合にも応用できること、も
ちろんである。FIG. 1 shows an embodiment of the method for manufacturing an optical fiber preform according to the present invention. The device system in the same figure is also almost the same as the device system in FIG. A moving mechanism 10 is provided. The configuration of this moving mechanism 10 is not particularly limited, but for example, a helmet stretched between two rollers 21, 21,
(A chain is also possible) The lower frame 3 is fixed to the lower frame 22, and the drive morph 23 is connected to the lower roller 22. Therefore, by driving the drive motor 23, the lower frame 3 can be moved with constant tension (for example, tension of about 1.5 to 2.0 kg/cm2). On the other hand, as a preferable example, this device system includes a temperature sensor I that detects the surface temperature of the optical fiber base material (quartz rond) 6.
This controller is connected to an external controller (control unit including a computer, etc.) 12, and this controller
- A monitor 13 such as a CRT or liquid crystal screen is connected to the roller 12, and from this controller 12, the above-mentioned moving mechanism 10, traverse mechanism 8, and oxyhydrogen burner 7 are connected.
control signals are output. As the temperature sensor 11, for example, a small TV camera with a built-in temperature sensor can be used, and this camera can capture a surface image of the optical fiber preform 6 to be cut, and at the same time measure and detect the surface temperature. I can do it. Therefore, in the present invention, the image information and temperature information from the camera are input to the external controller 12, and compared with the optimum disconnection temperature set in advance in the controller 12, and when the actual measured temperature matches, , the moving mechanism] O is driven at the optimum timing, the lower frame 3 is lowered 6 with a constant tension, the lower end of the optical fiber base material 6 is cut off, and then the lower end of the optical fiber base material 6 is cut out. Once completed, the oxyhydrogen burner 7 is retracted to a predetermined position by the traverse mechanism 8. Thereby, the cutting is performed smoothly and a good opening shape can be obtained without variation. Further, the operator can also directly observe the heating state of the surface of the optical fiber preform 6 through the monitor 13 connected to the controller 12. In addition, in the above embodiment, the moving mechanism 10 of the lower frame 3
In this example, IIJ? is controlled by the controller 12, but the present invention is not limited to this. IIJ? It can also be sold wholesale. In addition to temperature detection, the camera with a built-in temperature sensor can also detect dust attached to the surface of the base material, and flame polishing can be performed by detecting this dust. Furthermore, it is also possible to use a radiation thermometer without an imaging mechanism (camera) as the temperature sensor, and to install the temperature sensor at the lower end of the optical fiber base material (for example, below the lower frame 3). Further, in the above embodiment, a vertical glass lathe 1 was used, but the present invention is not limited thereto, and it goes without saying that it can also be applied to a horizontal glass lathe.
以上の説明から明らかなように本発明に係る光ファイバ
母材の製造方法によれば、次のような優れた効果が得ら
れる。
（１）、線引き工程前の前処理において、電動式の下部
フレームの移動機構を設け、母材の切離時の張力をある
一定値に制御するため、スムーズな切り離しが自動的に
行われる。したがって、作業者の負担が大幅に軽減され
、もちろん最適タイミングの判断は不要となり、また、
視覚への悪影響、視覚障害などの問題は根本的に解決さ
れる。
（２）、また、下部フレームの移動機構と共に、光ファ
イバ母材の表面温度を検出する温度センサを併設すれば
、この温度情報により、外部のコントローラを介して、
トラバース機構の移動、酸水素バーナの火炎制御、下部
フレームの移動機構の各制御が行われるため、各工程の
自動化が可能となり、大幅な省力化が図れる。
（３）、もちろん、これらの自動化により、作業環境の
改善も図ることができる。As is clear from the above description, according to the method for manufacturing an optical fiber preform according to the present invention, the following excellent effects can be obtained. (1) In the pretreatment before the wire drawing process, an electric lower frame moving mechanism is provided to control the tension at a certain value when cutting the base material, so that smooth separation is automatically performed. Therefore, the burden on the operator is greatly reduced, and of course there is no need to judge the optimal timing.
Problems such as adverse effects on vision and visual impairment will be fundamentally resolved. (2) Also, if a temperature sensor that detects the surface temperature of the optical fiber base material is installed together with the movement mechanism of the lower frame, this temperature information can be used to
Since the movement of the traverse mechanism, the flame control of the oxyhydrogen burner, and the movement mechanism of the lower frame are controlled, each process can be automated, resulting in significant labor savings. (3) Of course, by automating these processes, it is possible to improve the working environment.
第１図は本発明に係る光ファイバ母材の製造方法を実施
するための装置系の一例を示した概略説明図、第２図は
従来の光ファイバ母材の製造方法を実施するだめの装置
系を示した概略説明図である。
図中、
１・・・・旋盤、
３・・・・下部フレーム、
６・・・・光ファイバ母材、
７・・・・酸水素バーナ、
８・・・・トラバース機構、
１０・・・移動機構、
１１・・・温度センサ、
１２・・・コントローラ、
１３・・・モニタ、
２３・・・駆動モータ、
特許出願人 藤倉電線株式会社FIG. 1 is a schematic explanatory diagram showing an example of an apparatus system for implementing the method for manufacturing an optical fiber preform according to the present invention, and FIG. 2 is an apparatus for implementing the conventional method for manufacturing an optical fiber preform. It is a schematic explanatory diagram showing a system. In the figure, 1... lathe, 3... lower frame, 6... optical fiber base material, 7... oxyhydrogen burner, 8... traverse mechanism, 10... movement Mechanism, 11...Temperature sensor, 12...Controller, 13...Monitor, 23...Drive motor, Patent applicant: Fujikura Electric Cable Co., Ltd.
Claims (1)
ファイバ母材の下端付近をバーナの火炎で加熱して切り
離し、口出し加工を行う工程において、前記光ファイバ
母材の切離時の張力をある一定値に制御することを特徴
とする光ファイバ母材の製造方法。In the process of gripping both ends of the optical fiber preform before the drawing process, heating the vicinity of the lower end of the optical fiber preform with a burner flame to cut it, and performing a lead-out process, when cutting the optical fiber preform, A method for manufacturing an optical fiber preform, characterized by controlling tension to a certain constant value.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2321636A JP2598339B2 (en) | 1990-11-26 | 1990-11-26 | Manufacturing method of optical fiber preform |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2321636A JP2598339B2 (en) | 1990-11-26 | 1990-11-26 | Manufacturing method of optical fiber preform |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04193732A true JPH04193732A (en) | 1992-07-13 |
| JP2598339B2 JP2598339B2 (en) | 1997-04-09 |
Family
ID=18134718
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2321636A Expired - Fee Related JP2598339B2 (en) | 1990-11-26 | 1990-11-26 | Manufacturing method of optical fiber preform |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2598339B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000059838A1 (en) * | 1999-03-30 | 2000-10-12 | Corning Incorporated | Method and apparatus for the thermal treatment of an object such as an optical fiber preform |
| US6314765B1 (en) | 1998-10-06 | 2001-11-13 | Alcatel | Method and apparatus for controlling the shape and position of a deformable object |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3683195A1 (en) * | 2019-01-15 | 2020-07-22 | Heraeus Quartz North America LLC | Automated large outside diameter preform tipping process |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60136431A (en) * | 1983-12-24 | 1985-07-19 | Matsushita Electric Ind Co Ltd | Answer back transmitter of distribution line carrier |
| JPS63151640A (en) * | 1986-12-13 | 1988-06-24 | Hitachi Cable Ltd | Apparatus for drawing glass rod |
-
1990
- 1990-11-26 JP JP2321636A patent/JP2598339B2/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60136431A (en) * | 1983-12-24 | 1985-07-19 | Matsushita Electric Ind Co Ltd | Answer back transmitter of distribution line carrier |
| JPS63151640A (en) * | 1986-12-13 | 1988-06-24 | Hitachi Cable Ltd | Apparatus for drawing glass rod |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6314765B1 (en) | 1998-10-06 | 2001-11-13 | Alcatel | Method and apparatus for controlling the shape and position of a deformable object |
| WO2000059838A1 (en) * | 1999-03-30 | 2000-10-12 | Corning Incorporated | Method and apparatus for the thermal treatment of an object such as an optical fiber preform |
| JP2002541045A (en) * | 1999-03-30 | 2002-12-03 | コーニング インコーポレイティッド | Method and apparatus for heat treatment of objects such as optical fiber preforms |
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|---|---|
| JP2598339B2 (en) | 1997-04-09 |
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