JPH06256034A - Apparatus for drawing glass preform for optical fiber - Google Patents
Apparatus for drawing glass preform for optical fiberInfo
- Publication number
- JPH06256034A JPH06256034A JP3850593A JP3850593A JPH06256034A JP H06256034 A JPH06256034 A JP H06256034A JP 3850593 A JP3850593 A JP 3850593A JP 3850593 A JP3850593 A JP 3850593A JP H06256034 A JPH06256034 A JP H06256034A
- Authority
- JP
- Japan
- Prior art keywords
- glass preform
- optical fiber
- bellows
- shaped cylinder
- heating furnace
- 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
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]
- C03B37/01446—Thermal after-treatment of preforms, e.g. dehydrating, consolidating, sintering
- C03B37/0146—Furnaces therefor, e.g. muffle tubes, furnace linings
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Physics & Mathematics (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Thermal Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
- Light Guides In General And Applications Therefor (AREA)
- Re-Forming, After-Treatment, Cutting And Transporting Of Glass Products (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は光ファイバ用ガラス母材
の延伸装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for drawing a glass preform for optical fibers.
【0002】[0002]
【従来の技術】光ファイバ用ガラス母材を延伸加工する
装置としては、例えば光ファイバ用ガラス母材の両端を
チャックにて水平に把持し、回転させながら加熱して水
平方向に張力を加えるガラス旋盤が知られている。該加
熱の手段としては燃焼ガスをバーナーに供給、点火して
生じる火炎により加熱する燃焼バーナーや、加熱炉があ
る。また、光ファイバ用ガラス母材を鉛直方向に保持
し、加熱炉内に挿入して鉛直方向に張力をかけ延伸する
装置も知られている。この場合、図2の(a),(b)
に示すように加熱炉(5)の上部に光ファイバ用ガラス母
材(4)を囲むような金属製円筒(3)を設けることが行わ
れている。なお、図2において(1)は上部チャック、
(2)及び(8)は石英製支持棒、(6)はヒーター、(7)は
下部チャック、(9)は光ファイバ用ガラス母材延伸体を
示す。2. Description of the Related Art An apparatus for stretching a glass preform for optical fibers is, for example, a glass in which both ends of the glass preform for optical fiber are horizontally held by chucks and heated while being rotated to apply tension in the horizontal direction. Lathes are known. Examples of the heating means include a combustion burner that supplies combustion gas to a burner and heats it with a flame generated by ignition, and a heating furnace. There is also known a device that holds a glass preform for optical fibers in a vertical direction, inserts it into a heating furnace, and applies tension in the vertical direction to draw the glass. In this case, (a) and (b) of FIG.
As shown in FIG. 2, a metal cylinder (3) surrounding the glass base material (4) for optical fiber is provided on the upper part of the heating furnace (5). In FIG. 2, (1) is the upper chuck,
(2) and (8) are quartz support rods, (6) is a heater, (7) is a lower chuck, and (9) is a glass base material stretched body for optical fiber.
【0003】[0003]
【発明が解決しようとする課題】金属製円筒を上部に取
り付けた加熱炉を有する従来の装置では、光ファイバ用
ガラス母材を挿入し完全に収納するために、光ファイバ
用ガラス母材の全長に対応した長さの金属製円筒が必要
となり、加熱炉本体及び光ファイバ用ガラス母材の延伸
装置が大型化するという問題があった。更には、金属製
円筒の長さに対応した全長を有する石英製支持棒を光フ
ァイバ用ガラス母材の上部に接続することも必要とな
る。また、加熱炉内の雰囲気を確保し、且つ断熱材の酸
化消耗を抑えるためには、加熱炉本体の気密性を維持
し、酸素の加熱炉内への侵入を防ぐことが効果的であ
る。延伸加工中は金属製円筒上部の石英製支持棒貫通部
にて、貫通穴と石英製支持棒外形とのクリアランスを狭
くし気密を確保するが、高い気密性を得るためには、石
英製支持棒の全長にわたっての高い外径均一性が要求さ
れる。前述の光ファイバ用ガラス母材の長さに対応した
全長と高い外径均一性を有する高価な石英製支持棒を必
要とするため、この従来装置では光ファイバ自体の生産
コストにも不利であった。本発明はこのような問題点の
解消を課題としてなされたものであり、新規な光ファイ
バ用ガラス母材延伸装置の提供を意図している。In a conventional apparatus having a heating furnace having a metal cylinder attached to the upper portion thereof, in order to insert and completely store the glass preform for optical fiber, the entire length of the glass preform for optical fiber is used. Therefore, a metal cylinder having a length corresponding to the above is required, and there is a problem that the heating furnace main body and the glass fiber preform for an optical fiber are enlarged in size. Furthermore, it is also necessary to connect a quartz support rod having a total length corresponding to the length of the metal cylinder to the upper part of the glass preform for optical fibers. Further, in order to secure the atmosphere in the heating furnace and suppress the oxidative consumption of the heat insulating material, it is effective to maintain the airtightness of the heating furnace main body and prevent oxygen from entering the heating furnace. During the stretching process, the quartz support rod penetration part in the upper part of the metal cylinder narrows the clearance between the through hole and the quartz support rod outline to ensure airtightness, but in order to obtain high airtightness, the quartz support High outer diameter uniformity over the entire length of the rod is required. Since an expensive quartz support rod having a full length corresponding to the length of the glass base material for an optical fiber and high outer diameter uniformity is required, this conventional device is disadvantageous to the production cost of the optical fiber itself. It was The present invention has been made to solve the above problems, and intends to provide a novel glass base material drawing apparatus for an optical fiber.
【0004】[0004]
【課題を解決するための手段】上記課題を解決するため
の手段として、本発明は光ファイバ用ガラス母材の両端
に取り付けた石英製支持棒を加熱炉外の可動式上下チャ
ックで鉛直方向に把持し該光ファイバ用ガラス母材部分
を加熱炉内に挿入して加熱する際に該可動式上下チャッ
クの鉛直方向移動速度を制御することにより光ファイバ
用ガラス母材の加熱部に垂直方向の張力を掛け一定の径
に延伸する装置において、加熱炉上部の光ファイバ用ガ
ラス母材挿入部分を囲む位置に気密性、柔軟性及び耐熱
性を有する蛇腹状円筒を有してなることを特徴とする光
ファイバ用ガラス母材の延伸装置を提供する。本発明の
特に好ましい実施態様として、上記上部チャックと一定
の距離を保ちながら上記蛇腹状円筒を連動させる機構を
有することにより、該上部チャックの移動に従い該蛇腹
状円筒が伸縮できるように構成されてなる上記延伸装置
が挙げられ、さらに上記連動させる機構が、上部チャッ
クに取り付けられたワイヤー巻取部より引き出されるワ
イヤーを上記蛇腹状円筒の上部フランジを接続した構成
を有し、該ワイヤーの張力を制御することにより上記蛇
腹状円筒を伸縮できるようにされてなるものを挙げるこ
とができる。また、本発明においては上記ワイヤーが常
に一定値以上の張力を確保するように構成されてなるこ
とが特に好ましく、上記ワイヤーが所定値以上の張力が
かかると自動的に送りだされ、かつ蛇腹状円筒に負荷さ
れる張力を制限する機構をワイヤー巻取部に有してなる
ことが望ましい。As a means for solving the above-mentioned problems, the present invention is to use quartz support rods attached to both ends of a glass preform for optical fibers in a vertical direction by a movable upper and lower chucks outside a heating furnace. By controlling the vertical movement speed of the movable upper and lower chucks when gripping and inserting the glass preform for optical fiber into the heating furnace and heating the same, the vertical direction to the heating portion of the glass preform for optical fiber is controlled. In a device for applying a tension and stretching to a constant diameter, it is characterized by having a bellows-shaped cylinder having airtightness, flexibility and heat resistance at a position surrounding a glass base material insertion portion for an optical fiber in an upper part of a heating furnace. An apparatus for stretching a glass preform for an optical fiber is provided. As a particularly preferred embodiment of the present invention, by having a mechanism for interlocking the bellows-shaped cylinder while keeping a constant distance from the top chuck, the bellows-shaped cylinder is configured to expand and contract as the top chuck moves. The above-mentioned stretching device can be mentioned, and the above-mentioned interlocking mechanism has a configuration in which a wire drawn from a wire winding section attached to an upper chuck is connected to an upper flange of the bellows-shaped cylinder, and the tension of the wire is An example of the bellows-shaped cylinder can be expanded and contracted by controlling. Further, in the present invention, it is particularly preferable that the wire is configured to always secure a tension of a certain value or more, and the wire is automatically fed out when a tension of a predetermined value or more is applied, and a bellows shape. It is desirable that the wire winding section has a mechanism for limiting the tension applied to the cylinder.
【0005】[0005]
【実施例及び作用】図1に本発明の延伸装置の一実施例
を示し、本発明を詳細に説明するが、本発明はこれに限
定されるものではない。図1の(a)に示すように光フ
ァイバ用ガラス母材(4)は上下両端に石英製支持棒
(4),(8)が接続され、また各々の石英製支持棒(4),(8)
は上部チャック(1)と下部チャック(7)により確実に把
持される。延伸加工開始時において、ワイヤー巻取部
(12) より提供される複数本のワイヤー(13) の張力を
制御して上部フランジ(11) を上昇させる。これに伴い
蛇腹状円筒(10) は伸び、光ファイバ用ガラス母材(6)
は完全に収納される。加熱炉(5)内部のヒーター(6)に
光ファイバ用ガラス母材(6)を加熱し、この際上部チャ
ック(1)と下部チャック(7)の移動速度を制御すること
により光ファイバ用ガラス母材(4)に張力を与え、一定
の外径に延伸する。この過程においても複数本のワイヤ
ー(13) の張力を制御し、上部フランジ(11) の水平バ
ランスを維持し、且つ滑らかに蛇腹式円筒(10) を畳ん
でゆく〔図1の(b)参照〕。EXAMPLES AND OPERATION FIG. 1 shows an example of the stretching apparatus of the present invention to explain the present invention in detail, but the present invention is not limited to this. As shown in FIG. 1 (a), the glass base material for optical fiber (4) is connected with quartz support rods (4), (8) at both upper and lower ends, and each quartz support rod (4), (8) 8)
Is reliably gripped by the upper chuck (1) and the lower chuck (7). At the start of the drawing process, the tension of the plurality of wires (13) provided by the wire winding section (12) is controlled to raise the upper flange (11). Along with this, the bellows-shaped cylinder (10) expands, and the glass preform for optical fiber (6)
Is completely stowed. The glass (5) for optical fiber is heated by the heater (6) inside the heating furnace (5), and the moving speed of the upper chuck (1) and the lower chuck (7) is controlled at this time to control the glass for optical fiber. Tension is applied to the base material (4) to stretch it to a constant outer diameter. In this process as well, the tension of the wires (13) is controlled, the horizontal balance of the upper flange (11) is maintained, and the bellows type cylinder (10) is smoothly folded (see (b) of Fig. 1). ].
【0006】本発明では従来の金属製円筒に代えて、気
密性、柔軟性及び耐熱性を兼備した伸縮可能な蛇腹状円
筒(10) を採用することにより、縮めた際(畳んだ際)
の長さを小さく抑えることができて加熱炉本体の大型化
を防ぎ、且つ必要とする石英製支持棒の長さも従来より
短くできた。即ち、延伸加工開始時の上部チャック位置
が低くなることにより上部チャック、下部チャックを昇
降させる装置の小型化が可能となる。更に、延伸加工中
において、光ファイバ用ガラス母材の下降と動機して気
密性を維持する石英製支持棒の貫通部の相対的な位置を
変えることなく共に下降することが可能であるため、ク
リアランスは変化せず、石英製支持棒の全長にわたる外
径の高い均一性は不要となり、高精度で高価な外径均一
な石英製支持棒を使用しなくてもよい。また、蛇腹状円
筒の最上部に金属製のフランジを取り付け、この金属製
フランジを上部チャックに取り付けたワイヤー巻取部か
ら提供される複数本のワイヤーと接続することにより、
光ファイバ用ガラス母材の下降と金属製フランジの下降
を同期させる構造が得られる。またその複数本のワイヤ
ーの張力をワイヤー巻取部にて制御することにより、金
属製フランジの水平バランスを維持でき、また石英製支
持棒と上部フランジの貫通部のクリアランスも維持でき
る。そして加熱炉の高い気密性も得られることから、加
熱炉内断熱材の酸化消耗速度が抑えられ、メンテナンス
の頻度を減らすことができる。本発明に用いる蛇腹状円
筒の具体的な材質としては、柔軟性と気密性を有する材
料と高温にも耐える耐熱性材料を組み合わせた複合材料
が好ましく、例えばAlコーティングを施したカーボン
繊維を内側に気密を保つためのシリコーン樹脂を外側に
なるよう張り合わせた複合材料が挙げられるが、柔軟
性、気密性及び耐熱性を兼備している材料であれば勿論
いずれも使用できる。In the present invention, instead of a conventional metal cylinder, an expandable and contractible bellows-like cylinder (10) having airtightness, flexibility and heat resistance is adopted, so that it can be contracted (when folded).
The length of the heating furnace can be kept small, the size of the heating furnace main body can be prevented from increasing, and the required length of the quartz support rod can be made shorter than before. That is, by lowering the position of the upper chuck at the start of the stretching process, it is possible to downsize the device for moving the upper chuck and the lower chuck up and down. Furthermore, during the stretching process, since it is possible to lower the glass base material for optical fiber and to lower it together without changing the relative position of the penetrating portion of the quartz support rod that maintains the airtightness by motivation, The clearance does not change, high uniformity of the outer diameter over the entire length of the quartz support rod is unnecessary, and it is not necessary to use a highly accurate and expensive quartz support rod having a uniform outer diameter. Further, by attaching a metal flange to the uppermost part of the bellows-shaped cylinder, and connecting this metal flange to a plurality of wires provided from the wire winding section attached to the upper chuck,
A structure for synchronizing the lowering of the glass preform for optical fiber and the lowering of the metal flange can be obtained. Further, by controlling the tension of the plurality of wires by the wire winding portion, it is possible to maintain the horizontal balance of the metal flange and also maintain the clearance between the quartz support rod and the penetrating portion of the upper flange. Since the airtightness of the heating furnace is also high, the rate of oxidation and consumption of the heat insulating material in the heating furnace can be suppressed, and the frequency of maintenance can be reduced. As a concrete material of the bellows-shaped cylinder used in the present invention, a composite material in which a material having flexibility and airtightness and a heat resistant material that can withstand high temperature are combined is preferable, and for example, carbon fiber coated with Al is provided inside. A composite material in which a silicone resin for adhering airtightness is bonded to the outside can be used, but any material can be used as long as it has flexibility, airtightness and heat resistance.
【0007】以上説明したように、本発明は加熱炉の上
部に取り付ける円筒として伸縮可能な蛇腹状円筒を採用
し、該蛇腹状円筒の上部フランジを上部チャックとワイ
ヤーで接続する構造により、加熱炉の小型化、安価な石
英性支持棒の使用、更には上部及び下部チャックの昇降
装置の小型化が図れ、光ファイバ生産コスト低減に非常
に効果がある。As described above, the present invention employs an expandable and contractible bellows-shaped cylinder as a cylinder to be attached to the upper part of the heating furnace, and has a structure in which the upper flange of the bellows-shaped cylinder is connected to the upper chuck with a wire. Can be downsized, an inexpensive quartz support rod can be used, and the lifting device for the upper and lower chucks can be downsized, which is very effective in reducing the production cost of optical fibers.
【図1】は本発明の装置の一実施態様の概略説明図であ
る。FIG. 1 is a schematic explanatory view of an embodiment of the apparatus of the present invention.
【図2】は従来装置の概略説明図である。FIG. 2 is a schematic explanatory view of a conventional device.
1 上部チャック、 2 石英製支持棒、 3 金属製
円筒、 4 光ファイバ用ガラス母材、 5 加熱炉、
6 ヒーター、 7 下部チャック、 8石英製支持
棒、 9 光ファイバ用ガラス延伸体、 10 蛇腹状
円筒、 11上部フランジ、 12 ワイヤー巻取部、
13 ワイヤー。1 upper chuck, 2 quartz support rod, 3 metal cylinder, 4 glass base material for optical fiber, 5 heating furnace,
6 heater, 7 lower chuck, 8 quartz support rod, 9 optical fiber glass stretched body, 10 bellows-shaped cylinder, 11 upper flange, 12 wire winding section,
13 wires.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 山崎 卓 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 (72)発明者 横山 佳生 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 Taku Yamazaki 1 Taya-cho, Sakae-ku, Yokohama-shi, Kanagawa Sumitomo Electric Industries, Ltd. Yokohama Works (72) Inventor Yoshio Yokoyama 1 Taya-cho, Sakae-ku, Yokohama, Kanagawa Sumitomo Electric Ki Industry Co., Ltd. Yokohama Works
Claims (5)
けた石英製支持棒を加熱炉外の可動式上下チャックで鉛
直方向に把持し該光ファイバ用ガラス母材部分を加熱炉
内に挿入して加熱する際に該可動式上下チャックの鉛直
方向移動速度を制御することにより光ファイバ用ガラス
母材の加熱部に垂直方向の張力を掛け一定の径に延伸す
る装置において、加熱炉上部の光ファイバ用ガラス母材
挿入部分を囲む位置に気密性、柔軟性及び耐熱性を有す
る蛇腹状円筒を有してなることを特徴とする光ファイバ
用ガラス母材の延伸装置。1. A quartz support rod attached to both ends of an optical fiber glass preform is vertically held by a movable upper and lower chucks outside the heating furnace, and the glass preform for optical fiber is inserted into the heating furnace. In the device that applies vertical tension to the heating part of the glass preform for optical fiber to stretch it to a constant diameter by controlling the vertical moving speed of the movable upper and lower chucks when heating by An apparatus for stretching a glass preform for an optical fiber, comprising a bellows-shaped cylinder having airtightness, flexibility and heat resistance at a position surrounding a glass preform for fiber insertion.
がら上記蛇腹状円筒を連動させる機構を有することによ
り、該上部チャックの移動に従い該蛇腹状円筒が伸縮で
きるように構成されてなる請求項1記載の光ファイバ用
ガラス母材の延伸装置。2. The bellows-shaped cylinder can be expanded and contracted according to the movement of the upper chuck by having a mechanism for interlocking the bellows-shaped cylinder while keeping a constant distance from the upper chuck. An apparatus for drawing a glass preform for an optical fiber as described.
取り付けられたワイヤー巻取部より引き出されるワイヤ
ーを上記蛇腹状円筒の上部フランジを接続した構成を有
し、該ワイヤーの張力を制御することにより上記蛇腹状
円筒を伸縮できるようにされてなることを特徴とする請
求項2記載の光ファイバ用ガラス母材の延伸装置。3. The interlocking mechanism has a structure in which a wire pulled out from a wire winding section attached to an upper chuck is connected to an upper flange of the bellows-shaped cylinder, and the tension of the wire is controlled. The apparatus for drawing a glass preform for an optical fiber according to claim 2, wherein the bellows-shaped cylinder is capable of expanding and contracting.
確保するように構成されてなることを特徴とする請求項
3記載の光ファイバ用ガラス母材の延伸装置。4. The apparatus for drawing a glass preform for an optical fiber according to claim 3, wherein the wire is configured to always maintain a tension of a certain value or more.
ると自動的に送りだされ、かつ蛇腹状円筒に負荷される
張力を制限する機構をワイヤー巻取部に有してなる請求
項3又は請求項4に記載の光ファイバ用ガラス母材の延
伸装置。5. The wire winding section has a mechanism for automatically sending out the wire when a tension of a predetermined value or more is applied, and for limiting a tension applied to the bellows-shaped cylinder. The apparatus for drawing a glass preform for an optical fiber according to claim 4.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3850593A JP2897580B2 (en) | 1993-02-26 | 1993-02-26 | Glass fiber preform stretching equipment for optical fiber |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3850593A JP2897580B2 (en) | 1993-02-26 | 1993-02-26 | Glass fiber preform stretching equipment for optical fiber |
Publications (2)
Publication Number | Publication Date |
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JPH06256034A true JPH06256034A (en) | 1994-09-13 |
JP2897580B2 JP2897580B2 (en) | 1999-05-31 |
Family
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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JP3850593A Expired - Fee Related JP2897580B2 (en) | 1993-02-26 | 1993-02-26 | Glass fiber preform stretching equipment for optical fiber |
Country Status (1)
Country | Link |
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JP (1) | JP2897580B2 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6138481A (en) * | 1998-01-27 | 2000-10-31 | Sumitomo Electric Industries, Inc. | Glassrod elongation heating furnance having double bellows |
EP2336092A1 (en) | 2009-12-03 | 2011-06-22 | Shin-Etsu Chemical Co., Ltd. | Glass preform drawing apparatus |
-
1993
- 1993-02-26 JP JP3850593A patent/JP2897580B2/en not_active Expired - Fee Related
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6138481A (en) * | 1998-01-27 | 2000-10-31 | Sumitomo Electric Industries, Inc. | Glassrod elongation heating furnance having double bellows |
EP2336092A1 (en) | 2009-12-03 | 2011-06-22 | Shin-Etsu Chemical Co., Ltd. | Glass preform drawing apparatus |
Also Published As
Publication number | Publication date |
---|---|
JP2897580B2 (en) | 1999-05-31 |
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Legal Events
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LAPS | Cancellation because of no payment of annual fees |