JPH0640738A - Method and device for drawing optical fiber preform - Google Patents
Method and device for drawing optical fiber preformInfo
- Publication number
- JPH0640738A JPH0640738A JP4193887A JP19388792A JPH0640738A JP H0640738 A JPH0640738 A JP H0640738A JP 4193887 A JP4193887 A JP 4193887A JP 19388792 A JP19388792 A JP 19388792A JP H0640738 A JPH0640738 A JP H0640738A
- Authority
- JP
- Japan
- Prior art keywords
- chuck
- stretching
- optical fiber
- fitting member
- base material
- 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
Landscapes
- Re-Forming, After-Treatment, Cutting And Transporting Of Glass Products (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
- Glass Melting And Manufacturing (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は光ファイバ用母材の延伸
方法及び延伸装置に関するもので、特に大型のガラス母
材も容易に延伸できる方法及び装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for drawing an optical fiber preform, and more particularly to a method and an apparatus for easily drawing a large glass preform.
【０００２】[0002]
【従来の技術】光ファイバの従来の製造方法を、例えば
気相軸付け法（Vapour-phase axial deposition metho
d, ＶＡＤ法と略す）で説明する。ＶＡＤ法は同心円状
多重管バーナにより酸水素火炎を形成し、この火炎中に
ガラス原料ガス、例えばＳｉＣｌ 4 ，ＳｉＨＣｌ3 等お
よび場合によってドーパント原料ガス例えばＧｅＣ
ｌ4 ，ＰＯＣｌ3 ，ＢＣｌ3 などを投入し、火炎加水分
解反応あいは酸化反応によりガラス微粒子を生成し、こ
のガラス微粒子を出発ロッドの先端あるいは外周にスス
付けし、、ガラス微粒子堆積体を合成し、その後これを
加熱炉にて透明化することにより、透明ガラスプリフォ
ームを得る方法である。次にこの方法を用いて光ファイ
バを具体的に作る方法を述べると、まず、上記方法を用
い、出発ロッド先端にドーパントを含むコアまたはコア
とその外周にクラッドの一部を有するコア母材を合成
し、ハロゲン系ガスで脱水した後、透明ガラス化する。
その後、この透明ガラスロッドの外周に更にクラッド用
ガラス微粒子堆積体を合成する。こうして得られたガラ
スロッドとガラス微粒子堆積体を再び、焼結炉で透明ガ
ラス化し、光ファイバ用プリフォームを得る。この後、
光ファイバ用プリフォームのガラス表面を火炎研磨した
後、電気炉あるいは酸水素バーナを用いて延伸し、所定
の太さのプリフォームロッドを作製する。このプリフォ
ームロッドを線引炉で紡糸することにより光ファイバが
得られる。ガラス微粒子堆積体を透明ガラス化して得た
プリフォームは、続く火炎研磨や延伸工程に付すため
に、当該プリフォームの先端にダミー棒が溶着等により
一体的に設けられた形状とし、該ダミー棒部分を把持し
て電気炉等の加熱炉にて溶融延伸している。2. Description of the Related Art A conventional method for manufacturing an optical fiber is described in, for example,
Vapor-phase axial deposition method
d, abbreviated as VAD method). VAD method is concentric
An oxyhydrogen flame is formed by the multi-tube burner, and in this flame
Glass source gas, eg SiCl Four, SiHCl3Etc.
And optionally a dopant source gas such as GeC
lFour, POCl3, BCl3Etc., add the flame water
During the decomposition reaction, glass particles are generated by the oxidation reaction,
Soot fine glass particles to the tip or outer circumference of the starting rod.
Attached, synthesize a glass particulate deposit, and then
By making it transparent in a heating furnace, transparent glass preform
Is a way to obtain a game. Then use this method to
To describe the concrete method of making a bar, first, use the above method.
A core or core containing dopant at the starting rod tip
And a core base material with a part of the clad around it
Then, after dehydration with a halogen-based gas, transparent glass is formed.
After that, for further cladding on the outer circumference of this transparent glass rod
A glass particle deposit is synthesized. Gala thus obtained
The sludge and the glass particle deposits are again transparentized in a sintering furnace.
Lathed to obtain a preform for optical fiber. After this,
The glass surface of the optical fiber preform was flame-polished
Then stretch using an electric furnace or oxyhydrogen burner
A preform rod having a thickness of is manufactured. This prefo
The optical fiber is produced by spinning the rod in the drawing furnace.
can get. Obtained by clear vitrification of glass particle deposits
The preform is for subsequent flame polishing and stretching processes
, A dummy rod is welded to the tip of the preform.
Hold the dummy rod part as an integrally provided shape
Melt drawing in a heating furnace such as an electric furnace.
【０００３】延伸工程の従来技術としては、例えば特公
昭６２−１６７２３６号公報に提案されているように、
図６において、鉛直方向に貫通した開口を有する加熱炉
（ガラス母材加熱炉）１１と、該ガラス母材加熱炉１１
の上方に設置され、且つ光ファイバ用母材（ガラス母
材）１の両端部に一体的に設けられた把持棒（ダミー
棒）１５，１６の一方１５を把持する上部チャック６
と、前記ガラス母材加熱炉１１の下方に設置され且つガ
ラス母材のもう一方の把持棒を把持する下部チャック７
からなる延伸装置で、該上下のチャック６，７で把持棒
１５，１６が把持された光ファイバ用母材１を該ガラス
母材加熱炉１１に通して加熱した状態で該上下のチャッ
クの一方を該ガラス母材加熱炉１１に対して相対的に近
づけるよう移動し、且つ他方のチャックを該ガラス母材
加熱炉１１に対して相対的に遠ざけるように移動するこ
とにより、ガラス母材１を延伸し、延伸母材１３とする
方法がある。As a conventional technique of the stretching process, for example, as proposed in Japanese Patent Publication No. 62-167236,
6, a heating furnace (glass base material heating furnace) 11 having an opening penetrating in the vertical direction, and the glass base material heating furnace 11
Upper chuck 6 for holding one of the holding rods (dummy rods) 15 and 16 installed above the optical fiber and integrally provided at both ends of the optical fiber preform (glass preform) 1.
And a lower chuck 7 installed below the glass base material heating furnace 11 for holding the other holding rod of the glass base material.
Of the upper and lower chucks 6 and 7 with the gripping rods 15 and 16 held by the upper and lower chucks 6 and 7 being heated through the glass base material heating furnace 11. By moving the chuck so as to be relatively close to the glass base material heating furnace 11 and the other chuck so as to be relatively away from the glass base material heating furnace 11. There is a method of drawing and forming the drawn base material 13.
【０００４】[0004]
【発明が解決しようとする課題】従来、この種の延伸方
法では、母材の上下に長尺のダミー棒を溶着一体化し、
該ダミー棒を加熱炉の上下に設けられたチャックで把持
することにより、光ファイバ用母材を延伸装置に固定し
ていた。従ってダミー棒を溶着一体化させた後は、その
全長が長くなり取扱いが容易ではなかった。また、ダミ
ー棒が長尺であるために延伸後の全長も長くなるため、
延伸装置も長くする必要があった。これに対し、ダミー
棒に嵌合部材を取り付け、該嵌合部材の部分をチャック
で把持すれれば、ダミー棒を短くすることができると考
えられる。しかし、嵌合部材で把持して延伸すると曲が
りやすい問題もある。本発明は、光フアイバ用母材に従
来の如く長尺のダミー棒を一体化せずに、しかも曲がり
なく延伸することを課題とするものであり、この課題を
解決することにより大型のプリフォームを高品質で高強
度に合成できる延伸方法及び装置を提供しようとするも
のである。Conventionally, in this type of stretching method, long dummy rods are welded and integrated above and below a base material,
The dummy rod was held by chucks provided above and below the heating furnace to fix the optical fiber preform to the drawing device. Therefore, after the dummy rods have been welded and integrated, the total length of the dummy rods becomes long and it is not easy to handle. Also, since the dummy rod is long, the total length after stretching is also long,
It was also necessary to lengthen the stretching device. On the other hand, if the fitting member is attached to the dummy rod and the portion of the fitting member is gripped by the chuck, the dummy rod can be shortened. However, there is also a problem in that when it is gripped by a fitting member and stretched, it tends to bend. SUMMARY OF THE INVENTION The present invention has an object to extend a long dummy rod into an optical fiber base material without integrating it as in the conventional case and to bend without bending. By solving this problem, a large preform is formed. The present invention is intended to provide a stretching method and device capable of synthesizing high quality and high strength.
【０００５】[0005]
【課題を解決するための手段】上記課題を解決する手段
として、本発明は光フアイバ用母材の両端に一体的に設
けられたダミー棒の各端部を各々嵌合する嵌合部材に固
定し、該嵌合部材を各々チャックで把持して加熱炉にて
加熱溶融することにより該光フアイバ用母材を鉛直方向
に延伸する方法において、延伸開始時は上部および下部
嵌合部材を各々上部および下部チャックで把持し、その
後に該上部または下部チャックを該上部または下部嵌合
部材から他の部分に掴み変える工程を有することを特徴
とする光ファイバ用母材の延伸方法を提供する。本発明
において特に好ましい実施態様として、上記延伸開始の
後に該上部または下部チャックを該上部または下部嵌合
部材から他の部分に掴み変える工程が、該加熱炉と該下
部チャックの間に設けられた独立に移動できる補助チャ
ックを併用して延伸し延伸を終了するものであることが
挙げられる。また、本発明は加熱炉及びその上下に設け
られた加熱炉の中心軸方向に独立して移動できる上部お
よび下部チャックからなる光ファイバ用母材の延伸装置
において、該加熱炉と該下部チャックとの間に、更に該
加熱炉の中心軸方向に独立して移動できる補助チャック
が設けられてなる光ファイバ用母材の延伸装置を提供す
る。本発明の延伸装置においては、上記下部チャックと
上記補助チャックとを同速度で移動させる手段を有して
なることが特に好ましい実施態様である。As a means for solving the above-mentioned problems, the present invention fixes each end of a dummy rod integrally provided at both ends of an optical fiber base material to a fitting member to be fitted therein. Then, in the method of vertically stretching the base material for optical fiber by gripping each of the fitting members with a chuck and heating and melting in a heating furnace, at the start of drawing, the upper and lower fitting members are respectively And a step of gripping with a lower chuck, and then gripping the upper or lower chuck from the upper or lower fitting member to another portion, and a method for stretching an optical fiber preform. In a particularly preferred embodiment of the present invention, a step of gripping the upper or lower chuck from the upper or lower fitting member to another portion after the start of stretching is provided between the heating furnace and the lower chuck. It may be mentioned that the auxiliary chuck that can be independently moved is used in combination and the drawing is completed. Further, the present invention is a drawing apparatus for an optical fiber preform comprising a heating furnace and upper and lower chucks that are independently movable in the central axis direction of the heating furnace provided above and below the heating furnace, and the heating furnace and the lower chuck. And an auxiliary chuck that can move independently in the central axis direction of the heating furnace between the two. In the stretching apparatus of the present invention, it is a particularly preferable embodiment that it has means for moving the lower chuck and the auxiliary chuck at the same speed.
【０００６】[0006]
【作用】本発明の方法によれば、光ファイバ用母材の延
伸において、ダミー棒の長さを短くすることができる。
すなわち、、例えば図１の（ｃ）部分に示すように、ダ
ミー棒の一部を嵌合部材４，６で代用することで、光フ
ァイバ用母材に溶着一体化すべきダミー棒を短くでき
る。ダミー棒は延伸前に溶着一体化してもよいが、短尺
であるために、光ファイバ用母材の形成前に溶着化して
おいても良い。すなわち、光ファイバ用母材はバーナよ
り形成される火炎中にガラス原料を投入し、火炎中での
火炎加水分解反応で生成されるガラス微粒子をガラスロ
ッドの外周に堆積させてから加熱透明化して得るのが一
般的である。従ってガラス微粒子を堆積させるガラスロ
ッドの両端にダミー棒を予め溶着一体化させておけば、
加熱透明化の後、直ちに延伸可能となる。プリフォーム
段階で改めてダミー棒を溶着する工程はプリフォームを
傷つけたり汚染したりする危険性があるが、このように
堆積前からダミー棒を溶着することでこの危険性を避け
ることができる。本発明は上記した光フアイバのコアを
含むガラスロッドに予めダミー棒を溶着しておいてガラ
ス微粒子堆積体を形成してゆく方法は勿論のこと、従来
のように焼結して得られた光フアイバ用プリフオームの
段階で新たにダミー棒を溶着して延伸する場合のいずれ
に適用しても有利である。そして、本発明によれば、延
伸開始後下部チャックを嵌合部材からダミー棒へ掴み変
えるために、延伸に必要な下部チャックの移動範囲を短
くすることができ、結果的に延伸装置の全長を短くする
ことが可能となる。すなわち、従来の延伸方法に較べ、
下部嵌合部材の長さに相当する分、下部チャックの移動
範囲を短くできる。According to the method of the present invention, the length of the dummy rod can be shortened when the optical fiber preform is stretched.
That is, for example, as shown in part (c) of FIG. 1, by substituting a part of the dummy rod with the fitting members 4 and 6, the dummy rod to be fused and integrated with the optical fiber preform can be shortened. The dummy rod may be welded and integrated before stretching, but since it is short, it may be welded before forming the optical fiber preform. That is, the optical fiber preform is prepared by charging the glass raw material into the flame formed by the burner, depositing the glass fine particles produced by the flame hydrolysis reaction in the flame on the outer periphery of the glass rod, and then heating and making it transparent. It is generally obtained. Therefore, if the dummy rods are previously welded and integrated at both ends of the glass rod on which the glass particles are deposited,
Immediately after heat-transparency, stretching is possible. Although the process of welding the dummy rods again in the preform stage has a risk of damaging or contaminating the preform, this risk can be avoided by welding the dummy rods before the deposition. The present invention is not limited to the method of forming a glass fine particle deposit by preliminarily welding a dummy rod to a glass rod containing the above-mentioned optical fiber core, and it is also possible to obtain a glass rod obtained by sintering as in the prior art. It is advantageous to be applied to any case where a dummy rod is newly welded and stretched at the stage of fiber preform. Further, according to the present invention, since the lower chuck is gripped and changed from the fitting member to the dummy rod after the stretching is started, the moving range of the lower chuck necessary for stretching can be shortened, and as a result, the total length of the stretching device can be reduced. It can be shortened. That is, compared to the conventional stretching method,
The moving range of the lower chuck can be shortened by the amount corresponding to the length of the lower fitting member.
【０００７】下部チャックの下部嵌合部材から下部ダミ
ー棒への掴み変えは、延伸開始後下部ダミー棒が加熱炉
外に出た後、補助チャックを下部チャックと同速度で移
動させながら、下部ダミー棒中央部付近を把持する。次
に下部チャックを開いて、下部嵌合部材を取り外す。そ
の後、下部チャックを上昇させるか、停止した状態で補
助チャックが下がってくるのを待つかして、下部チャッ
クを下部ダミー棒下端の位置に持ってくる。下部チャッ
クを補助チャックと同速度で移動させながら、下部チャ
ックで下部ダミー棒下端を把持し、次いで補助チャェク
を開いて移動を停止させる。その結果、これらの操作の
間、延伸は中断することなく進行し、下部チャックの下
部嵌合部材から下部ダミー棒への掴み変えが完了する。
これらの操作を可能にするため、補助チャックには下部
チャックと同速度で移動できる機能が必要である。To change the grip of the lower chuck from the lower fitting member to the lower dummy rod, after the lower dummy rod comes out of the heating furnace after the start of stretching, the auxiliary chuck is moved at the same speed as the lower chuck while the lower dummy is being moved. Hold near the center of the rod. Next, the lower chuck is opened and the lower fitting member is removed. After that, the lower chuck is moved to the position of the lower end of the lower dummy rod by raising the lower chuck or waiting for the auxiliary chuck to come down in a stopped state. While moving the lower chuck at the same speed as the auxiliary chuck, the lower chuck grips the lower end of the lower dummy rod, and then the auxiliary chuck is opened to stop the movement. As a result, during these operations, stretching proceeds uninterrupted, completing the regrabbing of the lower chuck from the lower mating member to the lower dummy bar.
In order to enable these operations, the auxiliary chuck needs to have the function of moving at the same speed as the lower chuck.
【０００８】更に、補助チャックを用いることで光ファ
イバ用母材の延伸が終了してからの掴み変えも可能とな
る。光ファイバ用母材の延伸中に下部チャックの掴み変
えを行なうことは、掴み変え前後で下部嵌合部材の中心
軸と下部ダミー母材の中心軸が僅かでもずれている場
合、延伸母材に曲がりの生じる可能性があるが、補助チ
ャックの併用でこれを防ぐことができる。Furthermore, by using the auxiliary chuck, it is possible to change the grip of the optical fiber preform after the stretching is completed. Changing the grip of the lower chuck during stretching of the optical fiber base material means that if the center axis of the lower fitting member and the center axis of the lower dummy base material are slightly misaligned before and after gripping change, Bending may occur, but this can be prevented by using an auxiliary chuck together.
【０００９】一方、光ファイバ用母材の延伸が終了した
後は、延伸母材を加熱炉外に出して取り出す工程が必要
となるが、そのために通常は、図６の（ｅ）部分に示す
ように延伸部端部を加熱して延伸細径化し、細径化され
た部分、すなわち細径部分１４を切断して延伸母材１３
を取り出す。本発明においても、図１の（ｇ）部分に示
すように細径化して細径部分１４を切断する。しかし、
延伸終了時には、延伸母材１３の重量を支えているのは
下部チャック７しかなく、そこで下部チャック７を開い
てしまうと、延伸母材１３を支えることができなくなっ
てしまい、延伸母材１３は加熱炉内の部分が軟化してい
るため徐々に落下する危険がある。このような問題に対
し、本発明の補助チャックの存在は、延伸母材を支える
ために用いることができるので非常に有利である。すな
わち、本発明では延伸ファイバ端部を加熱して延伸細径
化する直前に、図２の（ｉ）部分、図３の（ｇ）部分お
よび図４の（ｆ）部分に示すように、補助チャック８で
延伸母材１３を把持して、補助チャック８と下部チャッ
ク７の両方で延伸母材１３を固定し、両チャックを同速
度で下降させて延伸部端部を延伸細径化する。この延伸
細径化工程においても、延伸母材を下部チャックと補助
チャックの両方で支えることは、下部チャックでのみ延
伸母材を支える場合に較べ、より安全に延伸細径化でき
る。特に、細径部分を切断して延伸母材を取り出すと
き、下部チャックのみで延伸母材を支えている場合は、
延伸母材が長尺になればその下端を支えるるため、かな
り不安定となる場合もあるが、補助チャックでも延伸母
材を支えることで安全面でも有利となる。On the other hand, after the drawing of the optical fiber preform is completed, a step of taking out the drawn preform by taking it out of the heating furnace is necessary. For this reason, it is usually shown in part (e) of FIG. As described above, the end portion of the stretched portion is heated to reduce the stretched diameter, and the reduced diameter portion, that is, the reduced diameter portion 14 is cut to draw the stretched base material 13.
Take out. Also in the present invention, as shown in part (g) of FIG. 1, the diameter is reduced and the small diameter portion 14 is cut. But,
At the end of the stretching, only the lower chuck 7 supports the weight of the stretch base material 13. If the lower chuck 7 is opened there, the stretch base material 13 cannot be supported, and the stretch base material 13 is not supported. There is a danger of gradually falling due to softening inside the heating furnace. In response to such a problem, the existence of the auxiliary chuck of the present invention is very advantageous because it can be used to support the stretch base material. That is, in the present invention, immediately before heating the end portion of the stretched fiber to reduce the diameter of the stretched fiber, as shown in the portion (i) of FIG. 2, the portion (g) of FIG. 3 and the portion (f) of FIG. The stretching base material 13 is gripped by the chuck 8, the stretching base material 13 is fixed by both the auxiliary chuck 8 and the lower chuck 7, and both chucks are lowered at the same speed to reduce the diameter of the stretching portion end portion. Also in this stretching and thinning step, supporting the stretching base material by both the lower chuck and the auxiliary chuck can more safely reduce the stretching diameter than supporting the stretching base material only by the lower chuck. In particular, when taking out the stretched base material by cutting the small diameter part, if the stretched base material is supported only by the lower chuck,
If the stretched base material becomes long, it will support the lower end of the stretched base material, which may cause considerable instability. However, supporting the stretched base material by the auxiliary chuck is also advantageous in terms of safety.
【００１０】なお、本発明における嵌合部材へのダミー
棒の固定の方法を更に詳しく説明すると、例えば図５に
示すように嵌合部材の一端に設けられた嵌合用凹部にダ
ミー棒を挿入し、両者に設けられた貫通穴に円柱状の耐
熱ピンを挿入することで固定できる。このとき、嵌合部
材の内径とダミー棒の外径との差（クリアランス）は
０．２ｍｍから４ｍｍの範囲にあり、且つ嵌合部材に挿
入される部分のダミー棒の長さが５０〜１５０ｍｍであ
ることが好ましい。なお、延伸中、嵌合部材の熱による
変形を防ぐため嵌合部材の温度が１２００℃を超えない
よう、ダミー棒の長さを決めておくことが望ましい。嵌
合部材の内径とダミー棒の外径との差は少ない程嵌合部
材の中心軸とダミー棒の中心軸が一致するが、０．２ｍ
ｍ未満になると、嵌合部材とダミー棒の加工精度をかな
り良くしないと挿入できない。また４ｍｍを越えると嵌
合部材の中心軸とダミー棒の中心軸がズレてしまい、延
伸後の母材に曲がりが生じてしまう。The method of fixing the dummy rod to the fitting member according to the present invention will be described in more detail. For example, as shown in FIG. 5, the dummy rod is inserted into a fitting recess provided at one end of the fitting member. It can be fixed by inserting a cylindrical heat resistant pin into the through holes provided in both. At this time, the difference (clearance) between the inner diameter of the fitting member and the outer diameter of the dummy rod is in the range of 0.2 mm to 4 mm, and the length of the dummy rod inserted into the fitting member is 50 to 150 mm. Is preferred. During the stretching, it is desirable to determine the length of the dummy rod so that the temperature of the fitting member does not exceed 1200 ° C. in order to prevent the fitting member from being deformed by heat. The smaller the difference between the inner diameter of the fitting member and the outer diameter of the dummy rod, the closer the center axis of the fitting member and the center axis of the dummy rod will be.
If it is less than m, the fitting member and the dummy rod cannot be inserted unless the machining precision is considerably improved. Further, if it exceeds 4 mm, the central axis of the fitting member and the central axis of the dummy rod are deviated from each other, and the base material after stretching is bent.
【００１１】また、嵌合部材の中心軸とダミー棒の中心
軸を更に良く一致させる方法がある。すなわち、図５の
（ｂ）部分に示すように、嵌合部材にダミー棒を挿入
し、両者に設けられた貫通穴に耐熱性の円柱状のピンを
挿入した後、嵌合部材に予め取り付けておいた嵌合部材
の軸中心に向かうボルトを締めることにより、ダミー棒
を確実に固定する。該ボルトの数は２〜８個が望まし
い。ボルトを締めてダミー棒をしっかりと固定すること
により、延伸中においても、嵌合部材の中心軸とダミー
棒の中心軸が一致したままとなる。なお、ボルトの材質
はカーボン、アルミナ等が望ましい。There is also a method in which the central axis of the fitting member and the central axis of the dummy rod are made to match each other better. That is, as shown in the part (b) of FIG. 5, after inserting the dummy rod into the fitting member and inserting the heat-resistant cylindrical pin into the through hole provided in both, it is attached to the fitting member in advance. The dummy rod is securely fixed by tightening the bolts that have been set toward the axis center of the fitting member. The number of bolts is preferably 2-8. By tightly fixing the dummy rod by tightening the bolt, the central axis of the fitting member and the central axis of the dummy rod remain aligned even during the stretching. The material of the bolt is preferably carbon, alumina or the like.
【００１２】このようなボルトの使用は、特に下部ダミ
ー棒と下部嵌合部材との固定においては、一層有効であ
る。すなわち、下部ダミー棒と下部嵌合部材は延伸の初
期の段階ではお互いに引っ張りあっているため、それぞ
れの中心軸が一直線となりやすい。しかし、延伸が進行
するにつれて、光フアイバ用母材の上部が軟化するよう
になるため、軟化している部分より下の重量が全て下部
嵌合ぶさいにかかるようになり、その結果、下部嵌合部
材と下部ダミー棒はお互いに押し合うようになる。その
とき、下部嵌合部材に下部ダミー棒がしっかり固定さて
いないと、それぞれの中心軸がずれてしまいって、延伸
母材が曲がってしまうからである。The use of such a bolt is more effective particularly in fixing the lower dummy rod and the lower fitting member. That is, since the lower dummy rod and the lower fitting member pull each other in the initial stage of stretching, their central axes tend to be aligned. However, as the stretching progresses, the upper part of the optical fiber base material softens, so that all the weight below the softened part is applied to the lower fitting cover, resulting in the lower fitting. The mating member and the lower dummy bar are pressed against each other. At that time, if the lower dummy rod is not firmly fixed to the lower fitting member, the respective central axes are displaced and the stretched base material is bent.
【００１３】以上述べてきたように、嵌合部材を用いて
延伸をする場合、嵌合部材の内径とダミー棒の外径との
差やボルトを用いてしっかり固定することなどが重要で
あるため、嵌合部材は熱によって変形しないことが好ま
しい。嵌合部材の材質は不純物の混入を防ぐためにも光
フアイバ用母材と同じ石英ガラスが望ましい。従って嵌
合部材が変形しないため、前記のようにダミー棒の長さ
は嵌合部材が１２００℃以下となるように決めることが
望ましい。As described above, when the extension is performed using the fitting member, it is important that the difference between the inner diameter of the fitting member and the outer diameter of the dummy rod or the use of a bolt to firmly fix the member. It is preferable that the fitting member is not deformed by heat. It is desirable that the material of the fitting member is the same quartz glass as the optical fiber base material in order to prevent the entry of impurities. Therefore, since the fitting member does not deform, it is desirable that the length of the dummy rod is determined so that the fitting member has a temperature of 1200 ° C. or less as described above.
【００１４】本発明においてコア母材の両端に一体化す
るダミー棒としては、通常溶融法あるいは合成法で作ら
れた石英ガラスが用いられる。多少のドーパント、不純
物などが含有されていても良いが、粘度が極端に低いも
のでは、焼結、または延伸時熱変形してしまうので好ま
しくない。In the present invention, as the dummy rods integrated with both ends of the core base material, quartz glass produced by a melting method or a synthesizing method is usually used. Although some dopants, impurities, etc. may be contained, those having an extremely low viscosity are not preferable because they are thermally deformed during sintering or stretching.
【００１５】[0015]
【実施例】以下本発明を実施例により具体的に説明する
が、本発明はこれに限定されるものではない。 〔実施例１〕図１の（ａ）部分〜（ｇ）部分に示す手順
に従い、本発明により光ファイバ用母材を延伸した。加
熱炉１１の下開口部に下ぶた１０を取り付けておき、炉
内の不活性ガス噴出口から不活性ガスを供給して炉内に
充満させた状態で、ヒーター１２により所定温度まで炉
温を上昇させる。次に、上下端にダミー棒２，３が取り
付けられた光ファイバ用母材１を上部チャック６に取り
付けられた上部嵌合部材４の下端に取り付け、両者に設
けられた貫通穴にアルミナ製の円柱状ピン挿入すること
により、光ファイバ用母材１を固定した〔図１の（ａ）
部分〕。なお、光ファイバ用母材１は外径５５ｍｍ、長
さ４００ｍｍであった。加熱炉１１内に光ファイバ用母
材１を挿入し、加熱炉１１の下開口部の下ぶた１０を取
り外して該下開口部より炉外に下部ダミー棒３の端部を
出し〔図１の（ｂ）部分〕、下部嵌合部材５に挿入し、
上記と同様にアルミナ製円柱状ピンで固定した。なお、
下ぶた１０を取り外す際には、上部嵌合部材４に取り付
けられた上下動可能な気密板９が加熱炉１１の上開口部
を塞いでいるので、炉内は不活性ガスで充満させられた
ままとなっている〔図１の（ｃ）部分〕。光ファイバ用
母材１の下端部をヒーター１２の位置に併せて、下部嵌
合部材５を下部チャック７で把持し、上部チャック６を
毎分１０ｍｍ／分で下降すると共に下部チャック７を５
３ｍｍ／分で下降し延伸を開始した。図１の（ｄ）部分
に示すように、延伸が進行して下部ダミー棒３が加熱炉
１１の外に出てきたところで上部チャック６、下部チャ
ック７の移動を止め、延伸を中断した〔図１の（ｄ）部
分〕。下部チャック７を開いて、下部嵌合部材５を取り
外し、下部チャック７を上昇して、下部ダミー棒３の端
部に位置を併せて、下部チャック７で下部ダミー棒の３
端部を把持し、延伸を再開した〔図１の（ｅ）部分〕。
延伸が更に進行して光ファイバ用母材１の上端部がヒー
ター１２の位置に達したところで、延伸を終了した〔図
１の（ｆ）部分〕。次に下部チャック７のみを下降させ
て、延伸部端部を細径化した。その後、細径部分１４を
切断して、延伸母材１３を取り出した〔図１の（ｇ）部
分〕。以上の操作により、外径２４ｍｍ、長さ２１００
ｍｍの延伸母材が得られた。本実施例において、光ファ
イバ用母材に取り付けたダミー棒の長さは上下とも２０
０ｍｍであった。EXAMPLES The present invention will now be specifically described with reference to examples, but the present invention is not limited thereto. [Example 1] According to the present invention, a preform for an optical fiber was drawn according to the procedure shown in parts (a) to (g) of Fig. 1. The lower lid 10 is attached to the lower opening of the heating furnace 11, and an inert gas is supplied from an inert gas outlet in the furnace to fill the inside of the furnace with the heater 12 to raise the furnace temperature to a predetermined temperature. To raise. Next, the optical fiber preform 1 having the dummy rods 2 and 3 attached to the upper and lower ends thereof is attached to the lower end of the upper fitting member 4 attached to the upper chuck 6, and the through holes provided in both are made of alumina. The optical fiber preform 1 was fixed by inserting a cylindrical pin [(a) of FIG. 1].
part〕. The optical fiber preform 1 had an outer diameter of 55 mm and a length of 400 mm. The optical fiber preform 1 is inserted into the heating furnace 11, the lower lid 10 of the lower opening of the heating furnace 11 is removed, and the end of the lower dummy rod 3 is taken out of the furnace through the lower opening [Fig. (B) part], inserted into the lower fitting member 5,
In the same manner as above, it was fixed with a columnar pin made of alumina. In addition,
When the lower lid 10 is removed, the vertically movable airtight plate 9 attached to the upper fitting member 4 blocks the upper opening of the heating furnace 11, so that the inside of the furnace was filled with an inert gas. It remains as it is [part (c) of FIG. 1]. The lower end of the optical fiber preform 1 is aligned with the position of the heater 12, the lower fitting member 5 is gripped by the lower chuck 7, the upper chuck 6 is lowered at 10 mm / min, and the lower chuck 7 is moved by 5 mm.
It was lowered at 3 mm / min and the stretching was started. As shown in part (d) of FIG. 1, when the lower dummy bar 3 comes out of the heating furnace 11 as the stretching proceeds, the movement of the upper chuck 6 and the lower chuck 7 is stopped, and the stretching is stopped [Fig. 1 (d) part]. The lower chuck 7 is opened, the lower fitting member 5 is removed, the lower chuck 7 is raised, and the lower chuck 7 is aligned with the end portion of the lower dummy rod 3, and the lower chuck 7 moves the lower dummy rod 3 into position.
The end portion was gripped and the stretching was restarted [portion (e) in Fig. 1].
When the drawing further progressed and the upper end of the optical fiber preform 1 reached the position of the heater 12, the drawing was finished [(f) part in FIG. 1]. Next, only the lower chuck 7 was lowered to reduce the diameter of the end of the extending portion. After that, the narrow diameter portion 14 was cut, and the stretched base material 13 was taken out (portion (g) in FIG. 1). With the above operation, the outer diameter is 24 mm and the length is 2100.
A mm base material was obtained. In this embodiment, the length of the dummy rod attached to the optical fiber preform is 20
It was 0 mm.
【００１６】〔実施例２〕図２の（ａ）部分〜（ｉ）部
分に示す手順に従って本発明による光ファイバ用母材の
延伸を行った。図２の（ａ）部分に示すように、上下ダ
ミー棒２，３が取り付けられた光ファイバ用母材１を上
部チャック６に取り付けられた上部嵌合部材４に取り付
けた。なお、光ファイバ用母材１はコアおよびクラッド
を一部を有するガラスロッドの両端に長さ３００ｍｍの
ダミー棒を予め溶着一体化しておき、該ガラスロッドと
ダミー棒の外周部にガラス微粒子を堆積させ、合成した
ガラスロッド−ガラス微粒子堆積体の複合体を加熱炉に
て加熱し、透明ガラス化することにより作成した。ま
た、延伸装置には、加熱炉１１と下部チャック７の間に
補助チャック８を設置した。先ず、実施例１と同様にし
て下部嵌合部材５を下部ダミー棒３に取り付け、下部チ
ャック７で下部嵌合部材５を把持して、延伸を開始した
〔図２の（ｂ），（ｃ）部分〕。延伸が進行して、下部
ダミー棒３が加熱炉１１の下開口部より出て、補助チャ
ック８の位置に下部ダミー棒３の中央部付近が到達した
時点で、補助チャック８を下部チャック７と同速度で下
降させた〔図２の（ｄ）部分〕。このように補助チャッ
ク８を下部チャック８と同速度で下降しつつ、補助チャ
ック８で下部ダミー棒３の中央部付近を把持、すなわち
掴み変えた〔図２の（ｅ）部分〕。次に下部チャック７
を開いて下部嵌合部材５をはずし、下部チャック７を上
昇させて下部ダミー棒３の下部の位置に合わせ、延伸を
行っている補助チャック８と同速度で下降させながら、
下部ダミー棒３を把持した〔図２の（ｆ）部分〕。補助
チャック８を開いて、移動を停止した〔図２の（ｇ）部
分〕。次に図２の（ｈ）に示すように、光ファイバ用母
材１の上端部がヒーター１２の位置に到達した時点で上
部チャック６および下部チャック７を停止して、延伸を
終了した。図２の（ｉ）に示すように、補助チャック８
で延伸母材１３を把持し、下部チャック７および補助チ
ャック８の両方を同速度で下降して、延伸母材１３の上
端部を延伸細径化した。その後、細径部分１４を切断し
て延伸母材１３を取り出した。以上の操作により、外径
２４ｍｍ、長さ２１００ｍｍの延伸母材が得られた。Example 2 The optical fiber preform according to the present invention was drawn according to the procedure shown in parts (a) to (i) of FIG. As shown in part (a) of FIG. 2, the optical fiber preform 1 to which the upper and lower dummy rods 2 and 3 were attached was attached to the upper fitting member 4 attached to the upper chuck 6. In the optical fiber preform 1, a dummy rod having a length of 300 mm was previously welded and integrated at both ends of a glass rod having a core and a clad, and glass fine particles were deposited on the outer periphery of the glass rod and the dummy rod. Then, the composite of the synthesized glass rod-glass fine particle deposit was heated in a heating furnace to form a transparent glass. Further, an auxiliary chuck 8 was installed between the heating furnace 11 and the lower chuck 7 in the stretching device. First, the lower fitting member 5 was attached to the lower dummy rod 3 in the same manner as in Example 1, the lower fitting member 5 was held by the lower chuck 7, and the stretching was started [(b) and (c in FIG. 2). )part〕. When the extension progresses, the lower dummy rod 3 comes out of the lower opening of the heating furnace 11, and when the vicinity of the central portion of the lower dummy rod 3 reaches the position of the auxiliary chuck 8, the auxiliary chuck 8 is connected to the lower chuck 7. It was lowered at the same speed [portion (d) of FIG. 2]. In this way, while the auxiliary chuck 8 was descending at the same speed as the lower chuck 8, the auxiliary chuck 8 gripped, i.e., changed, the vicinity of the central portion of the lower dummy rod 3 (portion (e) in FIG. 2). Next, lower chuck 7
Open, remove the lower fitting member 5, raise the lower chuck 7 to align with the position of the lower portion of the lower dummy rod 3, and lower it at the same speed as the auxiliary chuck 8 that is stretching,
The lower dummy rod 3 was gripped [portion (f) in FIG. 2]. The auxiliary chuck 8 was opened and the movement was stopped [(g) part in FIG. 2]. Next, as shown in (h) of FIG. 2, when the upper end of the optical fiber preform 1 reaches the position of the heater 12, the upper chuck 6 and the lower chuck 7 are stopped and the stretching is completed. As shown in FIG. 2 (i), the auxiliary chuck 8
The drawn base material 13 was gripped by, and both the lower chuck 7 and the auxiliary chuck 8 were lowered at the same speed, and the upper end portion of the drawn base material 13 was drawn and thinned. Then, the thin diameter portion 14 was cut and the stretched base material 13 was taken out. By the above operation, a stretched base material having an outer diameter of 24 mm and a length of 2100 mm was obtained.
【００１７】〔実施例３〕３図の（ａ）部分〜（ｇ）部
分に示す手順で、本発明により光ファイバ用母材を延伸
した。図３の（ａ）部分〜（ｄ）部分に示すように、補
助チャック８が設置された延伸装置に実施例２と同様に
して光ファイバ用母材１を取り付け、延伸を開始した。
延伸中は下部チャック７で掴み変えることなくファイバ
用母材１の上端部がヒーター１２の位置に到達するまで
延伸した。その後、上部チャック６，下部チャック７の
下降を停止し、補助チャック８で延伸母材１３を把持し
た〔３図の（ｅ）部分〕。次に下部チャック７を開い
て、下部嵌合部材５を取り外し、下部チャック７を上昇
させて下部ダミー棒３の端部の位置に合わせ、下部ダミ
ー棒３を把持した〔図３の（ｆ）部分〕。この後、実施
例２と同様に光ファイバ用母材１の延伸残部分を細径化
し、該細径部分１４を切断して延伸母材１３を取り外し
た〔図３の（ｇ）部分〕。以上の操作により、外径２４
ｍｍ、長さ２１００ｍｍの延伸母材が得られた。Example 3 An optical fiber preform was drawn according to the present invention by the procedure shown in parts (a) to (g) of FIG. As shown in parts (a) to (d) of FIG. 3, the optical fiber preform 1 was attached to the drawing device provided with the auxiliary chuck 8 in the same manner as in Example 2, and the drawing was started.
During the stretching, the upper end of the fiber preform 1 was stretched until it reached the position of the heater 12 without being gripped by the lower chuck 7. Thereafter, the lowering of the upper chuck 6 and the lower chuck 7 was stopped, and the stretched base material 13 was held by the auxiliary chuck 8 [part (e) in FIG. 3]. Next, the lower chuck 7 is opened, the lower fitting member 5 is removed, the lower chuck 7 is lifted to align with the position of the end of the lower dummy rod 3, and the lower dummy rod 3 is gripped [(f) in FIG. 3]. part〕. After that, as in Example 2, the diameter of the unstretched portion of the optical fiber preform 1 was reduced, the thin diameter portion 14 was cut, and the stretched preform 13 was removed [portion (g) in FIG. 3]. With the above operation, the outer diameter is 24
A drawn base material having a length of 2 mm and a length of 2100 mm was obtained.
【００１８】実施例１，２，３において、外径５５ｍ
ｍ、長さ４００ｍｍの光ファイバ用母材を外径２４ｍ
ｍ、長さ２１００ｍｍの延伸母材に延伸する場合、ダミ
ー棒の長さは２００ｍｍ〜３００ｍｍ程度で設備高さは
４３００ｍｍ程度となる。図６に示した従来の延伸方法
および装置によれば、ダミー棒は上下とも１０００ｍｍ
程度必要になり、設備高さは４７００ｍｍ程度も必要と
なることに比較すると、本発明の効果は明らかである。In Examples 1, 2 and 3, the outer diameter is 55 m.
m, 400 mm long base material for optical fiber, outer diameter 24 m
In the case of drawing on a drawn base material having a length of m and a length of 2100 mm, the length of the dummy rod is about 200 mm to 300 mm and the equipment height is about 4300 mm. According to the conventional stretching method and apparatus shown in FIG.
The effect of the present invention is clear when compared with the fact that the equipment height is required to be about 4700 mm.
【００１９】〔実施例４〕長さ４００ｍｍ、外径６０ｍ
ｍの光ファイバ用母材の両端に、外径３０．０ｍｍ、長
さ３００ｍｍのダミー棒を溶着一体化した。ダミー棒を
溶着一体化した側と反対側の端部には軸方向と垂直に内
径４ｍｍの貫通穴を予め設けておいた。光ファイバ延伸
装置は図４（ａ）〜（ｆ）部分に示す構成を有し、光フ
ァイバ用母材１の固定は上部，下部ダミー棒２，３を各
々上部，下部嵌合部材６，７に挿入し、両者の貫通穴に
アルミナピンを挿入して固定した。さらに、下部ダミー
棒３は下部嵌合部材５に取り付けられた４本のカーボン
製ボルトで締めつけ固定した。 上部、下部嵌合部材
４，５のダミー棒挿入部分の内径は３０．５ｍｍ、また
上部，下部ダミー棒２，３の外径は各々３０．０ｍｍで
あった。上部ダミー棒２の上部嵌合部材４内に挿入され
た長さは６０ｍｍ、下部ダミー棒３の下部嵌合部材５内
に挿入された長さは１００ｍｍであった。下部嵌合部材
５を固定した後、上部チャック６を上昇させて光ファイ
バ用母材１の下端をヒーター１２の位置に合わせ、下部
チャック７で下部嵌合部材５を把持した（図４の（ｃ）
部分）。ヒーター温度１９５０℃とし、光ファイバ用母
材１が充分に加熱された後、上部チャック６を速度１０
ｍｍ／分で下降し、同時に下部チャック７を速度５４ｍ
ｍ／分で下降させた（図４の（ｄ）部分）。上部チャッ
ク６を３００ｍｍ下降させた時点で延伸を終了した（図
４の（ｅ）部分）。このとき、補助チャック８を用い
て、延伸母材１３を図４の（ｅ）部分に示すように把持
した。次に、補助チャック８と下部チャック７を同速度
で下降させることにより、延伸部上端を図４の（ｆ）に
示すように延伸、細径化し、該細径部分１４を切断する
ことにより延伸母材１３を上部ダミー棒２から分離し
た。なお、延伸工程中での嵌合部材の最高温度は１００
０℃であった。曲がり等なく延伸できた。[Embodiment 4] Length 400 mm, outer diameter 60 m
A dummy rod having an outer diameter of 30.0 mm and a length of 300 mm was welded and integrated to both ends of the base material for optical fiber of m. A through hole having an inner diameter of 4 mm was previously provided in the end portion on the side opposite to the side where the dummy rods were welded and integrated, perpendicular to the axial direction. The optical fiber drawing device has a structure shown in FIGS. 4A to 4F, and the optical fiber preform 1 is fixed by fixing the upper and lower dummy rods 2 and 3 to the upper and lower fitting members 6 and 7, respectively. Then, an alumina pin was inserted into both through holes and fixed. Further, the lower dummy rod 3 was fastened and fixed with four carbon bolts attached to the lower fitting member 5. The inner diameters of the dummy rod insertion portions of the upper and lower fitting members 4 and 5 were 30.5 mm, and the outer diameters of the upper and lower dummy rods 2 and 3 were 30.0 mm. The length of the upper dummy rod 2 inserted into the upper fitting member 4 was 60 mm, and the length of the lower dummy rod 3 inserted into the lower fitting member 5 was 100 mm. After fixing the lower fitting member 5, the upper chuck 6 is raised to align the lower end of the optical fiber preform 1 with the position of the heater 12, and the lower chuck 7 grips the lower fitting member 5 ((in FIG. 4). c)
part). After the heater temperature is set to 1950 ° C. and the optical fiber preform 1 is sufficiently heated, the upper chuck 6 is moved at a speed of 10
Lowering at a speed of 54 m
It was lowered at m / min ((d) part in FIG. 4). The stretching was completed when the upper chuck 6 was lowered by 300 mm (portion (e) in FIG. 4). At this time, using the auxiliary chuck 8, the stretched base material 13 was gripped as shown in part (e) of FIG. Next, by lowering the auxiliary chuck 8 and the lower chuck 7 at the same speed, the upper end of the stretched portion is stretched and reduced in diameter as shown in FIG. 4 (f), and the thin portion 14 is cut and stretched. The base material 13 was separated from the upper dummy rod 2. The maximum temperature of the fitting member during the stretching process is 100.
It was 0 ° C. It could be stretched without bending.
【００２０】[0020]
【発明の効果】本発明による延伸方法および装置を用い
れば、従来の如く光ファイバ用母材に長尺のダミー母材
を融着一体化する必要がなく設備高さを短くできること
に加え、光ファイバ用母材を形成するためのガラスロッ
ドに予めダミー棒を溶着一体化させておけば、光ファイ
バ用母材を形成後直ちに延伸可能となるので、工程簡略
化と共に、母材汚染、傷付け等の危険を低減できる。ま
た、下部チャックで下部嵌合部材から下部ダミー棒へ掴
み変えることにより、光ファイバ用母材の延伸に必要な
下部チャック移動範囲を短くすることができ、この点で
も設備高さを短くすることが可能となる。更に、加熱炉
と下部チャックとの間に補助チャックを設けることによ
り、下部チャックの掴み変えも延伸を中断することなく
可能となり、延伸母材の取り出しも安全に行なうことが
できる。また補助チャックの併用により掴み変えの際の
中心軸のズレを防げるので延伸母材の曲がりも防止でき
る。EFFECTS OF THE INVENTION By using the drawing method and apparatus according to the present invention, it is not necessary to fuse and integrate a long dummy preform with an optical fiber preform as in the conventional case, and the equipment height can be shortened. If the dummy rod is previously welded and integrated to the glass rod for forming the fiber preform, it can be stretched immediately after the optical fiber preform is formed, so that the process can be simplified and the preform is contaminated and scratched. Can reduce the risk of. Also, by moving the lower chuck from the lower fitting member to the lower dummy rod, it is possible to shorten the range of movement of the lower chuck necessary for stretching the optical fiber preform. Is possible. Further, by providing an auxiliary chuck between the heating furnace and the lower chuck, the lower chuck can be gripped and changed without interrupting the drawing, and the drawn base material can be taken out safely. Further, by using the auxiliary chuck together, it is possible to prevent the center axis from being displaced when the grip is changed, so that the bending of the stretched base material can be prevented.
【図１】本発明の一実施態様を工程の順に示す概略説明
図である。FIG. 1 is a schematic explanatory view showing an embodiment of the present invention in the order of steps.
【図２】本発明の他の実施態様を工程の順に示す概略説
明図である。FIG. 2 is a schematic explanatory view showing another embodiment of the present invention in the order of steps.
【図３】本発明の他の実施態様を工程の順に示す概略説
明図である。FIG. 3 is a schematic explanatory view showing another embodiment of the present invention in the order of steps.
【図４】本発明の他の実施態様を工程の順に示す概略説
明図である。FIG. 4 is a schematic explanatory view showing another embodiment of the present invention in the order of steps.
【図５】本発明におけるダミー棒の嵌合部材の固定の一
具体例を説明する概略図である。FIG. 5 is a schematic view illustrating a specific example of fixing a fitting member of a dummy rod according to the present invention.
【図６】従来法を工程の順に示す概略説明図である。FIG. 6 is a schematic explanatory view showing a conventional method in order of steps.
１ 光ファイバ用母材 ２ 上部ダミー棒 ３ 下部ダミー棒 ４ 上部嵌合部材 ５ 下部嵌合部材 ６ 上部チャック ７ 下部チャック ８ 補助チャック ９ 気密板 １０ 下ぶた １１ 加熱炉 １２ ヒーター １３ 延伸母材 １４ 細径部分 １５ 上部把持棒 １６ 下部把持棒 1 Base Material for Optical Fiber 2 Upper Dummy Rod 3 Lower Dummy Rod 4 Upper Fitting Member 5 Lower Fitting Member 6 Upper Chuck 7 Lower Chuck 8 Auxiliary Chuck 9 Airtight Plate 10 Lower Lid 11 Heating Furnace 12 Heater 13 Stretching Base Material 14 Fine Diameter part 15 Upper grip bar 16 Lower grip bar
───────────────────────────────────────────────────── フロントページの続き (72)発明者 向井 克蔵 神奈川県横浜市栄区田谷町１番地 住友電 気工業株式会社横浜製作所内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsuzo Mukai 1 Taya-cho, Sakae-ku, Yokohama-shi, Kanagawa Sumitomo Electric Industries, Ltd. Yokohama Works
Claims (8)
られたダミー棒の各端部を各々嵌合する嵌合部材に固定
し、該嵌合部材を各々チャックで把持して加熱炉にて加
熱溶融することにより該光フアイバ用母材を鉛直方向に
延伸する方法において、延伸開始時は上部および下部嵌
合部材を各々上部および下部チャックで把持し、その後
に該上部または下部チャックを該上部または下部嵌合部
材から他の部分に掴み変える工程を有することを特徴と
する光ファイバ用母材の延伸方法。1. A heating furnace in which each end of a dummy rod integrally provided at both ends of an optical fiber base material is fixed to a fitting member to be fitted, and the fitting member is gripped by a chuck. In the method of vertically stretching the base material for optical fiber by heating and melting at, the upper and lower fitting members are respectively gripped by the upper and lower chucks at the start of stretching, and then the upper or lower chuck is A method for extending an optical fiber preform, comprising a step of gripping the upper or lower fitting member to another part.
ックを該下部嵌合部材から該下部ダミー棒に掴み変えて
該下部嵌合部材を取り外し、続いて該下部ダミー棒を把
持した該下部チャックを移動させることにより延伸され
た母材の上端部分を細径化して該細径部分を切断するこ
とにより延伸された母材を該上部ダミー棒から分離する
ことを特徴とする請求項１記載の光ファイバ用母材の延
伸方法。2. In the final stage of the stretching, the lower chuck is gripped from the lower fitting member to the lower dummy rod, the lower fitting member is removed, and then the lower chuck holding the lower dummy rod is removed. 2. The light according to claim 1, wherein the upper end portion of the stretched base material is reduced in diameter by moving, and the stretched base material is separated from the upper dummy rod by cutting the reduced diameter portion. A method for drawing a fiber preform.
ャックを該上部または下部嵌合部材から他の部分に掴み
変える工程が、該加熱炉と該下部チャックの間に設けら
れた独立に移動できる補助チャックを併用して延伸し延
伸を終了するものであることを特徴とする請求項１記載
の光ファイバ用母材の延伸方法。3. The step of gripping the upper or lower chuck from the upper or lower fitting member to another portion after the start of the stretching can be independently moved provided between the heating furnace and the lower chuck. The method for drawing an optical fiber preform according to claim 1, wherein the auxiliary chuck is also used for drawing and the drawing is finished.
ックを該下部嵌合部材から該下部ダミー棒に掴み変えて
該下部嵌合部材を取り外し、続いて該下部ダミー棒を把
持した該下部チャックを移動させることにより延伸され
た母材の上端部分を細径化して該細径部分を切断するこ
とにより延伸された母材を該上部ダミー棒から分離する
ことを特徴とする請求項３記載の光ファイバ用母材の延
伸方法。4. In the final stage of the stretching, the lower chuck is gripped from the lower fitting member to the lower dummy rod, the lower fitting member is removed, and then the lower chuck holding the lower dummy rod is removed. 4. The light according to claim 3, wherein an upper end portion of the stretched base material is reduced in diameter by moving and the reduced diameter portion is cut to separate the stretched base material from the upper dummy rod. A method for drawing a fiber preform.
した該下部チャックと同速度で上記補助チャックを下降
させながら延伸の途中で該補助チャックで該下部ダミー
棒の中部を把持した後、該下部チャックを開いて該下部
嵌合部材を取り外し、次に該下部チャックを該補助チャ
ックに相対的に近づけ、該下部チャックを該補助チャッ
クと同速度で下降させた状態で該下部チャックで該下部
ダミー棒下部を把持し、該補助チャックを開くことによ
り、延伸を中断することなく該下部チャックを該下部嵌
合部材から該下部ダミー棒に掴み変えることを特徴とす
る請求項３または請求項４記載の光ファイバ用母材の延
伸方法。5. The middle part of the lower dummy rod is gripped by the auxiliary chuck during the stretching while lowering the auxiliary chuck at the same speed as the lower chuck gripping the lower fitting member in the stretching, The lower chuck is opened and the lower fitting member is removed, then the lower chuck is brought relatively close to the auxiliary chuck, and the lower chuck is lowered at the same speed as the auxiliary chuck. The grip of the lower part of the dummy rod and the opening of the auxiliary chuck allow the lower chuck to be gripped and changed from the lower fitting member to the lower dummy bar without interrupting the stretching. A method for stretching a base material for an optical fiber as described above.
母材の上部を上記補助チャックにより把持し、該補助チ
ャックと該下部チャックを同速度で移動させることによ
り延伸された母材の上端部分を細径化して該細径部を切
断することにより延伸された母材を該上部ダミー棒から
分離することを特徴とする請求項３ないし請求項５のい
ずれかに記載の光ファイバ用母材の延伸方法。6. The upper portion of the base material stretched by gripping the upper portion of the base material stretched in the final stage of the stretching by the auxiliary chuck and moving the auxiliary chuck and the lower chuck at the same speed. The optical fiber preform according to any one of claims 3 to 5, wherein the preform stretched by reducing the diameter and cutting the narrow portion is separated from the upper dummy rod. Stretching method.
の中心軸方向に独立して移動できる上部および下部チャ
ックからなる光ファイバ用母材の延伸装置において、該
加熱炉と該下部チャックとの間に、更に該加熱炉の中心
軸方向に独立して移動できる補助チャックが設けられて
なる光ファイバ用母材の延伸装置。7. A drawing apparatus for an optical fiber preform, which comprises an upper furnace and a lower chuck that can be independently moved in the central axis direction of the heating furnace and heating furnaces provided above and below the heating furnace, the heating furnace and the lower chuck. An optical fiber preform stretching device further comprising an auxiliary chuck that is independently movable in the central axis direction of the heating furnace.
を同速度で移動させる手段を有してなることを特徴とす
る請求項６記載の光ファイバ用母材の延伸装置。8. The apparatus for drawing an optical fiber preform according to claim 6, further comprising means for moving the lower chuck and the auxiliary chuck at the same speed.
Priority Applications (15)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19388792A JP3141546B2 (en) | 1992-07-21 | 1992-07-21 | Drawing method and drawing apparatus for preform for optical fiber |
| CA002099942A CA2099942C (en) | 1992-07-09 | 1993-07-06 | Method and apparatus for drawing glass preform for optical fiber |
| AU41751/93A AU659020B2 (en) | 1992-07-09 | 1993-07-06 | Method and apparatus for drawing glass preform for optical fiber |
| DE69324963T DE69324963T2 (en) | 1992-07-09 | 1993-07-08 | Process for drawing glass preforms for optical fiber |
| EP93110950A EP0578244B1 (en) | 1992-07-09 | 1993-07-08 | Method for drawing glass preform for optical fiber |
| EP97100122A EP0770583B1 (en) | 1992-07-09 | 1993-07-08 | Method for drawing glass proform for optical fiber |
| EP98119047A EP0885853B1 (en) | 1992-07-09 | 1993-07-08 | Apparatus for drawing a glass preform for optical fibers |
| DE69328572T DE69328572T2 (en) | 1992-07-09 | 1993-07-08 | Method and device for drawing glass preforms for optical fibers |
| DE69331917T DE69331917T2 (en) | 1992-07-09 | 1993-07-08 | Device for drawing a glass preform for optical fibers |
| KR1019930012908A KR970006995B1 (en) | 1992-07-09 | 1993-07-09 | Method and apparatus for production of glass preform for optical fiber |
| US08/370,233 US5674306A (en) | 1992-07-09 | 1995-01-09 | Method and apparatus for drawing glass preform for optical fiber |
| AU13547/95A AU668331B2 (en) | 1992-07-09 | 1995-02-28 | Method and apparatus for drawing a glass preform for optical fiber |
| AU13546/95A AU668330B2 (en) | 1992-07-09 | 1995-02-28 | Method for drawing a glass preform for optical fiber |
| KR1019960077413A KR970007945B1 (en) | 1992-07-21 | 1996-12-30 | Method and apparatus for drawing glass preform for optical fiber |
| US08/795,016 US5788734A (en) | 1992-07-09 | 1997-02-05 | Method for drawing glass preform for optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19388792A JP3141546B2 (en) | 1992-07-21 | 1992-07-21 | Drawing method and drawing apparatus for preform for optical fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0640738A true JPH0640738A (en) | 1994-02-15 |
| JP3141546B2 JP3141546B2 (en) | 2001-03-05 |
Family
ID=16315393
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP19388792A Expired - Lifetime JP3141546B2 (en) | 1992-07-09 | 1992-07-21 | Drawing method and drawing apparatus for preform for optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3141546B2 (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002543024A (en) * | 1999-04-07 | 2002-12-17 | ヘレウス・テネボ・アクチェンゲゼルシャフト | Method for producing cylindrical parts from quartz glass and apparatus suitable for this |
| JP2004026637A (en) * | 2002-06-26 | 2004-01-29 | Heraeus Tenevo Ag | Method for manufacturing glass tube |
| JP2005119933A (en) * | 2003-10-20 | 2005-05-12 | Sumitomo Electric Ind Ltd | Manufacturing method of optical fiber and stretching unit of glass preform therefor |
| JP2006193369A (en) * | 2005-01-13 | 2006-07-27 | Shin Etsu Chem Co Ltd | Method and apparatus for processing quartz glass bar and carbon tool used for the same |
| JP2009132586A (en) * | 2007-11-30 | 2009-06-18 | Sumitomo Electric Ind Ltd | Drawing method for glass preform |
-
1992
- 1992-07-21 JP JP19388792A patent/JP3141546B2/en not_active Expired - Lifetime
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002543024A (en) * | 1999-04-07 | 2002-12-17 | ヘレウス・テネボ・アクチェンゲゼルシャフト | Method for producing cylindrical parts from quartz glass and apparatus suitable for this |
| JP4634617B2 (en) * | 1999-04-07 | 2011-02-16 | ヘレウス・テネボ・ゲゼルシャフト・ミット・ベシュレンクテル・ハフツング | Method for producing cylindrical parts from quartz glass and equipment suitable for this |
| JP2004026637A (en) * | 2002-06-26 | 2004-01-29 | Heraeus Tenevo Ag | Method for manufacturing glass tube |
| JP2005119933A (en) * | 2003-10-20 | 2005-05-12 | Sumitomo Electric Ind Ltd | Manufacturing method of optical fiber and stretching unit of glass preform therefor |
| JP2006193369A (en) * | 2005-01-13 | 2006-07-27 | Shin Etsu Chem Co Ltd | Method and apparatus for processing quartz glass bar and carbon tool used for the same |
| JP4583938B2 (en) * | 2005-01-13 | 2010-11-17 | 信越化学工業株式会社 | Method and apparatus for processing quartz glass rod |
| JP2009132586A (en) * | 2007-11-30 | 2009-06-18 | Sumitomo Electric Ind Ltd | Drawing method for glass preform |
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|---|---|
| JP3141546B2 (en) | 2001-03-05 |
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