JPS59217633A - Apparatus for manufacturing optical fiber preform - Google Patents
Apparatus for manufacturing optical fiber preformInfo
- Publication number
- JPS59217633A JPS59217633A JP9031683A JP9031683A JPS59217633A JP S59217633 A JPS59217633 A JP S59217633A JP 9031683 A JP9031683 A JP 9031683A JP 9031683 A JP9031683 A JP 9031683A JP S59217633 A JPS59217633 A JP S59217633A
- Authority
- JP
- Japan
- Prior art keywords
- quartz tube
- tube
- control valve
- orifice
- orifice plate
- 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
- C03B37/012—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]
- C03B37/018—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] by glass deposition on a glass substrate, e.g. by inside-, modified-, plasma-, or plasma modified- chemical vapour deposition [ICVD, MCVD, PCVD, PMCVD], i.e. by thin layer coating on the inside or outside of a glass tube or on a glass rod
- C03B37/01846—Means for after-treatment or catching of worked reactant gases
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General 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)
- Glass Melting And Manufacturing (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
Abstract
Description
【発明の詳細な説明】 本発明は光フアイバ母材の製造装置に関する。[Detailed description of the invention] The present invention relates to an optical fiber preform manufacturing apparatus.
光フアイバ母材の代表的な製造方法として所謂内付けＣ
ＶＤ法が知られている。The so-called internal attachment C is a typical manufacturing method for optical fiber base material.
The VD method is known.
同方法は低損失の元ファイバを製造するとψう点て優れ
ているが、次のような欠点があった。Although this method is excellent in that it produces a low-loss original fiber, it has the following drawbacks.
即ち、石英管の内周面にガラス層を形成する際、間管は
例えば１４００〜１６００℃の高温に加熱されるため軟
化踵そパ自身の表面張力により次第に収縮することにな
り、やがてはその内面に均質なガラス層を形成すること
が困難になり、従って形成可能なガラス層の厚さが限ら
れてくると共に１本のプリフォームからｌｋｍ程度の光
ファイバしか得られず長尺の光ファイバを得ることがで
きなかった。That is, when forming a glass layer on the inner circumferential surface of the quartz tube, the inner tube is heated to a high temperature of, for example, 1,400 to 1,600 degrees Celsius, so it gradually contracts due to the surface tension of the softened heel itself. It becomes difficult to form a homogeneous glass layer on the inner surface, and therefore the thickness of the glass layer that can be formed is limited, and only an optical fiber of about 1 km can be obtained from one preform, resulting in a long optical fiber. I couldn't get it.
この傾向はガラス形成に特に高温を要する純石英ガラス
（Ｓ１０□）を形成する場合に著しく、またガラス形成
時に石英管が高温に加熱されるため、石英管断面に楕円
化などの変形が生じ易く、得られるプリフォーム、ひい
ては光ファイバはその断面の寸法精度が劣化するという
問題があった。This tendency is particularly noticeable when forming pure silica glass (S10□), which requires high temperatures for glass formation, and since the quartz tube is heated to a high temperature during glass formation, deformations such as ovalization are likely to occur in the cross section of the quartz tube. However, there is a problem in that the dimensional accuracy of the cross section of the resulting preform and, ultimately, the optical fiber deteriorates.
そこでこれに対処するため、ガラス形成時、石英管の内
圧を外圧よりも高く保持することにより石英管の径を一
定に制御することが既に提案されている。To deal with this, it has already been proposed to control the diameter of the quartz tube to a constant value by maintaining the internal pressure of the quartz tube higher than the external pressure during glass formation.
その具体的方法としては、石英管の収縮力に均衡する内
圧を発生させるため、間管の一方の端部たる排気口に絞
りを設け、この絞りを調節する、という方法が一般的で
ある。As a specific method, a common method is to provide a throttle at the exhaust port at one end of the quartz tube and adjust the throttle in order to generate an internal pressure that is balanced with the contraction force of the quartz tube.
この絞りの大きさは、石英管の大きさ及びガラス形成速
度、つまりガラス原料の送り量等により異なるが、直径
にして数謳程度である。The size of this aperture varies depending on the size of the quartz tube and the speed of glass formation, that is, the feed rate of glass raw materials, etc., but it is about a few degrees in diameter.
従ってこの絞りは、排気中に存在する多量のＳｉｏ２、
ＧｅＯ２等のガラス微粉によって直ちに閉塞されること
になり、所定の製造条件を維持することができなかった
。Therefore, this aperture restricts the large amount of Sio2 present in the exhaust gas,
It was immediately blocked by glass fine powder such as GeO2, making it impossible to maintain predetermined manufacturing conditions.
そこでかかる不都合を回避すべく、石英管に接続された
排気筒の端部に円錐状の栓を設け、この栓を駆動させる
ことにより排気口の大きさを調節するという方法が既に
提案されている。In order to avoid this inconvenience, a method has already been proposed in which a conical plug is provided at the end of the exhaust pipe connected to the quartz tube, and the size of the exhaust port is adjusted by driving this plug. .
しかしかかる方法において、栓の円錐面では、ガラス微
粉の付着、脱落が一様ではなく、シか１
、栓。微小ヶ移動−えよっ、も排気Ｄ（Ｄ断面積ヵ８
大きく変化するため、石英管の外径の測定値に応じて管
径を精密に制御することが困難であった０
′本発明は、石英管の端部と排気口との間にオリフィス
板を設けると共に同板上を摺動自在な調節弁によって同
板の開口面積を変化させることにより上記問題点を解決
しようというもので、これを図面に示す実施例を参照し
ながら説明すると、第１図に示すよって１石英管１は、
回転部２によって回転自在に保持されており、この石英
管１の一端は、配管系３を介してガラス原料供給部４に
接続されている。However, in this method, the adhesion and falling off of fine glass powder is not uniform on the conical surface of the stopper;
,plug. Minute movement - Wow, exhaust D (D cross section area 8
Because the diameter varies greatly, it is difficult to precisely control the diameter of the quartz tube according to the measured value of the outer diameter of the quartz tube. The above-mentioned problem is solved by changing the opening area of the plate with a control valve that is provided and slidable on the plate.This will be explained with reference to an embodiment shown in the drawings. As shown in , 1 quartz tube 1 is
The quartz tube 1 is rotatably held by a rotating section 2, and one end of the quartz tube 1 is connected to a frit supply section 4 via a piping system 3.
同供給部からは石英管１内に気相のガラス原料、例えば
酸素と共に四塩化硅素、四塩化ゲルマニウム等が導入さ
れるようになっている。From the supply section, glass raw materials in a vapor phase, such as silicon tetrachloride, germanium tetrachloride, etc., are introduced into the quartz tube 1 along with oxygen.
上記石英管１を加熱するための）く−ナによる加熱部６
Ｖｉ、石英管１の長手方向沿いに移動自在な移動台６に
載置されており、この移動台６にはさらに石英管１の外
径を測定する測定器７が載置されている。A heating section 6 using a heater (for heating the quartz tube 1)
Vi, the quartz tube 1 is placed on a movable table 6 that is movable along the longitudinal direction, and a measuring device 7 for measuring the outer diameter of the quartz tube 1 is further placed on the movable table 6.
上記加熱部５は配管系８を介して原料供給部４に連結さ
れており、同供給部から加熱部６に酸素が供給されるよ
うになっている。The heating section 5 is connected to the raw material supply section 4 via a piping system 8, and oxygen is supplied from the supply section to the heating section 6.
上記石英管１の他端には、その内圧を調節するための内
圧調節部９が連結されている。The other end of the quartz tube 1 is connected to an internal pressure adjusting section 9 for adjusting its internal pressure.
同調節部９は第２図に示すように、排気口１０を有する
密閉状の排気室１１を備えており、石英管１の他端は連
結パイプ１２を介して排気室１１に連結されている。As shown in FIG. 2, the adjustment section 9 includes a sealed exhaust chamber 11 having an exhaust port 10, and the other end of the quartz tube 1 is connected to the exhaust chamber 11 via a connecting pipe 12. .
同室１１は、オリフィス１３を有するオリフィス板１４
によって流入部１５と流出部１６とに仕切られており、
流入部１５には石英管１が連結されており、また流出部
１６には排気口１０が設けられている。The same chamber 11 has an orifice plate 14 having an orifice 13.
It is partitioned into an inflow part 15 and an outflow part 16 by
A quartz tube 1 is connected to the inflow section 15, and an exhaust port 10 is provided at the outflow section 16.
上記オリフィス板１４には、その表面上を摺動自在な調
節弁１７が設けられており、量弁は回転軸１８を中心に
回転自在となっている。The orifice plate 14 is provided with a control valve 17 that is slidable on its surface, and the quantity valve is rotatable about a rotation shaft 18.
上記オリフィス１３の開口面積は、この調節弁１７の回
転によって変化させられるようになっていればよく、従
ってオリフィス１３の形状は第３図に示すように湾曲状
の長孔に限られず、調節弁１７の回転によって開口面積
が変化する形状であれば任意に選択し得る。The opening area of the orifice 13 need only be changed by the rotation of the control valve 17. Therefore, the shape of the orifice 13 is not limited to a curved long hole as shown in FIG. Any shape can be selected as long as the opening area changes with the rotation of 17.
上記排気室１１には、さらにシリンダ１９が設ケラれて
おり、ピストンロッド２ｏの先端にはオリフィス１３の
断面形状を形どった掃除具２１が取り付けられており、
シリンダ１９作動時、掃除具２１はオリフィス１３を貫
通し、オリフィス１３を塞ぐガラス微粉を除去するよう
になっている。A cylinder 19 is further installed in the exhaust chamber 11, and a cleaning tool 21 having the cross-sectional shape of the orifice 13 is attached to the tip of the piston rod 2o.
When the cylinder 19 is activated, the cleaning tool 21 penetrates the orifice 13 and removes fine glass powder that blocks the orifice 13.
このシリンダ１９はシリンダ駆動部２２によって駆動さ
せられ、捷た上記回転軸１８は調節弁駆動部２３によっ
て駆動させられるようになっている。This cylinder 19 is driven by a cylinder drive section 22, and the twisted rotating shaft 18 is driven by a control valve drive section 23.
これら駆動部２２．２３は、制御部２４によって制御さ
れ、また調節弁駆動部２３は調節計２５からの制御信号
によっても制御されるようになっている。These drive units 22 and 23 are controlled by a control unit 24, and the control valve drive unit 23 is also controlled by a control signal from a controller 25.
上記回転部２には、リミットスイッチ２６ａ１２６ｂが
設置されており、同スイッチに移動台６が接触すること
により、移動台６の移動方向が検知される。A limit switch 26a126b is installed in the rotating section 2, and when the moving table 6 comes into contact with the switch, the moving direction of the moving table 6 is detected.
例えば移動台６の復工程Ａの開始は、移動台６のリミッ
トスイッチ２６ａへの接触によって検知されることにな
り、同スイッチからの検知信号は制御部２４に供給され
、制御部２４はさらに同信号を受けることＫよｐ１上記
駆動部２２．２３に後述の如き指令を与える。For example, the start of the return process A of the moving table 6 is detected by the contact of the moving table 6 with the limit switch 26a, and a detection signal from the switch is supplied to the control unit 24, which further controls the limit switch 26a. Receiving the signal Kyop1 gives commands as described below to the drive sections 22 and 23.
尚、第２図において、２７Ｖｉガラス微粉を捕捉するた
めの捕集器であって、流入部１６に設置されている。In addition, in FIG. 2, it is a collector for capturing 27Vi glass fine powder, and is installed in the inflow part 16.
ここで内圧調整部９の動作について述べると、石英管１
内でのガラス堆積時、即ち移動台６の往工程Ｂ時、調節
弁１７はオリフィス１３の一部を塞いでおり、このよう
な調節弁１７の位置は調節計２５からの制御信号によっ
て設定される。Now, to describe the operation of the internal pressure adjusting section 9, the quartz tube 1
During the glass deposition in the chamber, that is, during the forward step B of the moving table 6, the control valve 17 closes a part of the orifice 13, and the position of the control valve 17 is set by a control signal from the controller 25. Ru.
即ち、測定器７からの検出信号と石英管１の外径の設定
値とが調節計２５において比較され、これらに差がある
場合には、制御信号が調節弁駆動部２３に供給され、調
節弁１７は石英管１の外径が設定値に維持される位置に
回転移動する。That is, the detection signal from the measuring device 7 and the set value of the outer diameter of the quartz tube 1 are compared in the controller 25, and if there is a difference between them, a control signal is supplied to the control valve drive unit 23 to perform the adjustment. The valve 17 is rotated to a position where the outer diameter of the quartz tube 1 is maintained at the set value.
従ってオリフィス１３がガラス微粉によって閉塞された
場合には、さらに新たな開口部が形成されることになる
ため、ガラス堆積時にオリフィス１３が完全に閉塞され
るというようなことがない。Therefore, if the orifice 13 is blocked by fine glass powder, a new opening will be formed, so that the orifice 13 will not be completely blocked during glass deposition.
そして移動台６が往工程Ｂを終り、リミットスイッチ２
６ａに接触すると、同スイッチは動作し、制御部２４に
信号を供給する。Then, the moving table 6 completes the forward process B, and the limit switch 2
When the switch 6a is touched, the switch is activated and supplies a signal to the control unit 24.
この信号を受けて制御部２４は調節弁駆動部２３にオリ
フィス全開の指令を、またシリンダ駆動部２２にシリン
ダ１９の１往復の指令を与える。In response to this signal, the control section 24 gives a command to the control valve drive section 23 to fully open the orifice, and a command to the cylinder drive section 22 to move the cylinder 19 back and forth once.
この指令によって、ピストンロッド２０の掃除具２１は
オリフィス１３に付着したガラス微粉を突き落すことに
なる。In response to this command, the cleaning tool 21 of the piston rod 20 will push down the fine glass powder adhering to the orifice 13.
こうしてシリンダ１９の１往復が終ったならば、調節弁
１７を元の位置に戻し、再び調節弁駆動部２３を調節引
２６の制御下に服させる。When one reciprocation of the cylinder 19 is completed in this manner, the control valve 17 is returned to its original position, and the control valve drive section 23 is brought under the control of the control puller 26 again.
以°」二の動作によって、長尺のプリフォームを製造す
る場合でも、石英管の外径制御を行うことが可能である
が、さらにプリフォームの大型化を行う場合、石英管１
から排出されるガラス微粉をオリフィス１３に達する手
酌で捕集するようにしておけばより効果的である。By the following two operations, it is possible to control the outer diameter of the quartz tube even when manufacturing a long preform, but when making the preform even larger, it is possible to control the outer diameter of the quartz tube.
It will be more effective if the glass fine powder discharged from the glass powder is collected by a hand cup that reaches the orifice 13.
第２図の捕集器２７はこのために設けられており、捕集
器２７としては例えば、テラレット、ネットリング、ラ
シヒリング等の充填材を重ねた充填層が用いられる。The collector 27 shown in FIG. 2 is provided for this purpose, and as the collector 27, for example, a packed bed in which fillers such as terraret, net rings, and Raschig rings are stacked is used.
以上のように本発明においては、石英管の他端に排気口
を有する排気室を連結すると共にこの排気室内に石英管
と排気口とを連通させるオリフィス板を設け、さらにこ
のオリフィス板を摺動ずゐことによって開口部の面積を
変化させる調節弁を設けたので、ガラス微粉によって絞
りが小さくなり、或いは閉塞された場合には、調節弁に
よって覆われたオリフィスの残部をさらに開状態にすれ
ばよく、従って所定の製造条件が維持されることになる
。As described above, in the present invention, an exhaust chamber having an exhaust port is connected to the other end of the quartz tube, an orifice plate is provided in the exhaust chamber to communicate the quartz tube and the exhaust port, and the orifice plate is slidably connected to the exhaust chamber. Since a control valve is provided that changes the area of the orifice by changing the area of the orifice, if the orifice becomes smaller or blocked by fine glass powder, the rest of the orifice covered by the control valve can be further opened. Therefore, the predetermined manufacturing conditions will be maintained.
また、調節弁はオリフィス板を摺動自在であるため、開
口部の面積を微調整でき、従って石英管の外径制御が精
密に行えることになり、長尺のプリフォームの製造が可
能になると共にプリフォームの寸法精度の向上、純石英
ガラスの形成が可能になる。In addition, since the control valve can slide freely on the orifice plate, the area of the opening can be finely adjusted, making it possible to precisely control the outer diameter of the quartz tube, making it possible to manufacture long preforms. At the same time, it becomes possible to improve the dimensional accuracy of the preform and form pure silica glass.
第１図（は本発明に係る装置の略示図、第２図は同装置
の要部を示す略示図、第３図は第２図のＡ−Ａ線におけ
る矢視図である。
１・・・・・石英管
２・・・・・回転部
４・・・・・原料供給部
５・・・・・加熱部
１０・・・・・排気口
１１・・・・・排気室
１４拳・・・・オリフィス板
１７・・・・・調節弁
特許出願人
代理人 弁理士 井 藤 誠
第１図
１１
第３図FIG. 1 is a schematic diagram of the device according to the present invention, FIG. 2 is a schematic diagram showing the main parts of the device, and FIG. 3 is a view taken along the line A-A in FIG. 2. ... Quartz tube 2 ... Rotating section 4 ... Raw material supply section 5 ... Heating section 10 ... Exhaust port 11 ... Exhaust chamber 14 fist ... Orifice plate 17 ... Control valve Patent applicant representative Patent attorney Makoto Ito Figure 1 11 Figure 3
Claims (1)
管の一端からその内部に気相のガラス原料を供給する原
料供給部と、上記石英管を加熱する加熱部とを備えた光
フアイバ母材の製造装置において、上記石英管の他端に
排気口を有する排気室を連結すると共にこの排気室内に
上記石英管と排気口とを連通させるオリフィス板を設置
し、さらにこのオリフィス板を摺動することによってそ
の開口部の面積を変化させる調節弁を設けたことを特徴
とする光フアイバ母材の製造装置。(1) A light that includes a rotating part that rotatably holds a quartz tube, a raw material supply part that supplies a vapor phase glass raw material from one end of the quartz tube to the inside of the quartz tube, and a heating part that heats the quartz tube. In the fiber base material manufacturing device, an exhaust chamber having an exhaust port is connected to the other end of the quartz tube, and an orifice plate is installed in the exhaust chamber to communicate the quartz tube and the exhaust port, and the orifice plate is further connected to the exhaust chamber. An apparatus for manufacturing an optical fiber base material, characterized in that it is provided with a control valve that changes the area of its opening by sliding.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9031683A JPS59217633A (en) | 1983-05-23 | 1983-05-23 | Apparatus for manufacturing optical fiber preform |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9031683A JPS59217633A (en) | 1983-05-23 | 1983-05-23 | Apparatus for manufacturing optical fiber preform |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS59217633A true JPS59217633A (en) | 1984-12-07 |
Family
ID=13995120
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9031683A Pending JPS59217633A (en) | 1983-05-23 | 1983-05-23 | Apparatus for manufacturing optical fiber preform |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59217633A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100374352B1 (en) * | 2000-03-23 | 2003-03-04 | 삼성전자주식회사 | Pressure controlling system and method of gas in optical fiber preform manufacturing process |
| EP1300371A2 (en) * | 2001-10-03 | 2003-04-09 | Alcatel | Method and device for manufacturing an optical fibre preform by the modified chemical vapour deposition process |
| EP1719739A1 (en) * | 2004-02-27 | 2006-11-08 | Sumitomo Electric Industries, Ltd. | Method and device for producing optical fiber matrix |
| EP2947056A1 (en) * | 2014-05-22 | 2015-11-25 | Draka Comteq B.V. | A method and a device for manufacturing an optical preform by means of an internal vapour deposition process, as well as corresponding substrate tube assembly |
-
1983
- 1983-05-23 JP JP9031683A patent/JPS59217633A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100374352B1 (en) * | 2000-03-23 | 2003-03-04 | 삼성전자주식회사 | Pressure controlling system and method of gas in optical fiber preform manufacturing process |
| EP1300371A2 (en) * | 2001-10-03 | 2003-04-09 | Alcatel | Method and device for manufacturing an optical fibre preform by the modified chemical vapour deposition process |
| EP1300371A3 (en) * | 2001-10-03 | 2003-08-13 | Alcatel | Method and device for manufacturing an optical fibre preform by the modified chemical vapour deposition process |
| EP1719739A1 (en) * | 2004-02-27 | 2006-11-08 | Sumitomo Electric Industries, Ltd. | Method and device for producing optical fiber matrix |
| EP1719739A4 (en) * | 2004-02-27 | 2011-06-22 | Sumitomo Electric Industries | Method and device for producing optical fiber matrix |
| EP2947056A1 (en) * | 2014-05-22 | 2015-11-25 | Draka Comteq B.V. | A method and a device for manufacturing an optical preform by means of an internal vapour deposition process, as well as corresponding substrate tube assembly |
| US9463994B2 (en) * | 2014-05-22 | 2016-10-11 | Draka Comteq B.V. | Method and a device for manufacturing an optical preform by means of an internal vapour deposition process, as well as corresponding substrate tube assembly |
| US9828279B2 (en) | 2014-05-22 | 2017-11-28 | Draka Comteq B.V. | Method and device for manufacturing an optical preform by means of an internal vapour deposition process, and a corresponding substrate tube assembly |
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