JPH08325030A - Method for maintaining optical fiber drawing heating furnace in shutdown and device therefor - Google Patents
Method for maintaining optical fiber drawing heating furnace in shutdown and device thereforInfo
- Publication number
- JPH08325030A JPH08325030A JP13439095A JP13439095A JPH08325030A JP H08325030 A JPH08325030 A JP H08325030A JP 13439095 A JP13439095 A JP 13439095A JP 13439095 A JP13439095 A JP 13439095A JP H08325030 A JPH08325030 A JP H08325030A
- Authority
- JP
- Japan
- Prior art keywords
- heating furnace
- optical fiber
- furnace
- inert gas
- heater
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
- C03B37/01—Manufacture of glass fibres or filaments
- C03B37/02—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor
- C03B37/025—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor from reheated softened tubes, rods, fibres or filaments, e.g. drawing fibres from preforms
- C03B37/029—Furnaces therefor
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2205/00—Fibre drawing or extruding details
- C03B2205/60—Optical fibre draw furnaces
- C03B2205/62—Heating means for drawing
- C03B2205/63—Ohmic resistance heaters, e.g. carbon or graphite resistance heaters
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、少なくともコアがガラ
スからなる光ファイバを製造するのに使用される光ファ
イバ線引き用加熱炉を、休転時に保管する方法及び装置
に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for storing a heating furnace for drawing an optical fiber, which is used for manufacturing an optical fiber having at least a core made of glass, at rest.
【０００２】[0002]
【従来の技術】コアがガラス、クラッドがポリマからな
る光ファイバ、或いはコア及びクラックがともにガラス
からなる光ファイバは、その光ファイバ母材を加熱炉に
より溶融線引きし、その外周にクラッド用ポリマ材或い
は被覆層用ポリマ材をコーティングする方法によって製
造される。2. Description of the Related Art An optical fiber whose core is made of glass and whose cladding is made of polymer, or an optical fiber whose core and crack are both made of glass are prepared by melting and drawing a base material of the optical fiber in a heating furnace, and then forming a polymer material for cladding on the outer periphery thereof. Alternatively, it is produced by a method of coating a polymer material for a coating layer.
【０００３】図４は、上記光ファイバの線引き装置の概
略を示す。光ファイバ製造時には、加熱炉１の上部側に
光ファイバ母材１８を供給し、その光ファイバ母材１８
をヒータ２で加熱し、加熱炉１の下部側から線引きされ
た光ファイバ１９を引出す。次いで、樹脂塗布装置１５
及び樹脂硬化装置１６によってクラッド用ポリマ材又は
被覆層用ポリマ材を被覆硬化させてクラッド又はポリマ
被覆層を形成したのち巻取機１７によって巻取るように
している。この線引き用の加熱炉１にはカーボン素材か
らなるヒータ２が設けられており、そのカーボン素材は
一般に耐酸化性がよくないため、運転中は不活性ガス開
閉弁５、ガス出入口４を介して不活性ガスを加熱炉内に
送るようにしている。FIG. 4 schematically shows the optical fiber drawing apparatus. At the time of manufacturing the optical fiber, the optical fiber preform 18 is supplied to the upper side of the heating furnace 1, and the optical fiber preform 18 is supplied.
Is heated by the heater 2, and the drawn optical fiber 19 is pulled out from the lower side of the heating furnace 1. Next, the resin coating device 15
Further, the clad polymer material or the coating layer polymer material is coated and cured by the resin curing device 16 to form the clad or the polymer coating layer, and then wound by the winder 17. The heating furnace 1 for wire drawing is provided with a heater 2 made of a carbon material. Since the carbon material generally has poor oxidation resistance, the inert gas on-off valve 5 and the gas inlet / outlet 4 are used during operation. An inert gas is sent into the heating furnace.
【０００４】従来、このように耐酸化性が劣るカーボン
素材からなるヒータは、空気中に含まれる酸素によって
も徐々に酸化が進行するので、光ファイバ製造を中断す
る休転時には加熱炉ヒータの酸化が進行しないように加
熱炉の上下の入口、出口用開口部に蓋を設けるともに、
加熱炉内を真空状態にして休転時保管する方法がとられ
ていた。Conventionally, a heater made of a carbon material having poor oxidation resistance is gradually oxidized by oxygen contained in the air, so that the heater of the heating furnace is oxidized during a rest period when the optical fiber production is interrupted. So that the heating does not proceed, lids are provided on the upper and lower inlets and outlets of the heating furnace,
A method has been adopted in which the heating furnace is evacuated and stored at rest.
【０００５】図３は従来の線引き装置の休転時の状況を
概略的に示すものである。具体的には、図３のように上
下の蓋体１３，１４を加熱炉１の入口、出口用開口部２
１，２２の上方および下方にシール用リング部材１１，
１1'を介して取付け、次にガス出入口４、真空開閉弁６
から内部の空気を排出させて内部を真空化し、この真空
力によって蓋体１３，１４を密着させるようにしてい
た。FIG. 3 schematically shows a state of a conventional wire drawing apparatus at rest. Specifically, as shown in FIG. 3, the upper and lower lids 13 and 14 are connected to the inlet and outlet openings 2 of the heating furnace 1.
Above and below 1, 22 are sealing ring members 11,
Mounted via 11 ', then gas inlet / outlet 4, vacuum on / off valve 6
The inside air is exhausted from the inside to make the inside vacuum, and the lids 13 and 14 are brought into close contact with each other by this vacuum force.
【０００６】[0006]
【発明が解決しようとする課題】上記のような休転方法
によって上下蓋体と加熱炉が完全密閉していれば空気の
流入がなく、何ら問題はないが、この上下蓋体は光ファ
イバ製造の線引き中には不要になる。そのため、上下蓋
体は脱着し易く、かつ簡単に持ち運びできる簡便な機構
になっている。If the upper and lower lids and the heating furnace are completely sealed by the above-described idling method, there will be no air flow, and there is no problem. It becomes unnecessary while drawing. Therefore, the upper and lower lids are easily detachable and have a simple mechanism that can be easily carried.
【０００７】このような上下蓋体に対する要求特性上、
これを完全密閉機構とすることは極めて困難であり、そ
のために微少な空気の流入は防ぎきれず、ヒータの酸化
が引き起こされてヒータ寿命を縮める結果になってい
た。さらに、カーボン酸化の微粉末化により、局所的な
弱糸部が並び易くなり、ファイバ破断回数が高くなる結
果となっていた。Due to the required characteristics of the upper and lower lids,
It is extremely difficult to make this a complete sealing mechanism, and therefore it is impossible to prevent the inflow of a minute amount of air, which results in the oxidation of the heater and shortens the life of the heater. Furthermore, due to the fine powder of carbon oxide, local weak yarns are easily aligned, resulting in a high number of fiber breakages.
【０００８】本発明の目的は、かかる従来技術の欠点を
解消し、休転時にもカーボン素材からなるヒータの酸化
劣化を防止することを可能にする光ファイバ線引き用加
熱炉の休転保管方法及び装置を提供することにある。An object of the present invention is to eliminate the drawbacks of the prior art, and to prevent the heater made of carbon material from being oxidized and deteriorated even at rest. To provide a device.
【０００９】[0009]
【課題を解決するための手段】上記目的を達成する本発
明の光ファイバ線引き用加熱炉の休転保管方法は、カー
ボン製ヒータを内蔵する光ファイバ線引き用加熱炉を休
転時に保管する際、加熱炉の出入口部分を加圧密閉可能
な蓋体により密閉し、かつ該加熱炉内部を不活性ガスに
より加圧状態にするものである。In order to achieve the above object, an idle storage method of a heating furnace for drawing an optical fiber according to the present invention is a method for storing the heating furnace for drawing an optical fiber containing a carbon heater at rest. The inlet / outlet portion of the heating furnace is sealed with a lid capable of pressure sealing, and the inside of the heating furnace is pressurized with an inert gas.
【００１０】また、本発明による光ファイバ線引き用加
熱炉の休転保管装置は、カーボン製ヒータを内蔵する光
ファイバ線引き用加熱炉の出入口部分に、加熱炉内部を
加圧密閉可能にする上下蓋体をそれぞれ配置し、かつ該
加熱炉の壁部に加熱炉内部へ不活性ガスを供給する不活
性ガス供給管を配置したことを特徴とするものである。Further, according to the present invention, there is provided a device for keeping a rest of a heating furnace for drawing an optical fiber, wherein an upper and lower lids for pressurizing and sealing the inside of the heating furnace are provided at the entrance and exit portions of the heating furnace for drawing an optical fiber containing a carbon heater. Each of the bodies is arranged, and an inert gas supply pipe for supplying an inert gas to the inside of the heating furnace is arranged on the wall portion of the heating furnace.
【００１１】本発明において光ファイバとは、少なくと
もコアがガラスからなっている必要があるが、そのコア
に施されたクラッドは、有機ポリマであっても、ガラス
であってもよい。また、コアとなる光ファイバ母材は、
ガラスの中でも石英ガラスが好ましい。また、本発明に
おいてカーボン製ヒータとしては、従来公知のものがい
ずれも使用することができ、通常は円筒形のものが使用
される。In the present invention, the optical fiber needs to have at least a core made of glass, and the clad provided on the core may be an organic polymer or glass. Also, the optical fiber preform that becomes the core is
Quartz glass is preferable among the glasses. In the present invention, as the carbon heater, any conventionally known heater can be used, and a cylindrical heater is usually used.
【００１２】上下蓋体は加熱炉内部を加圧密閉可能な構
造になっていることが必要がある。加圧密閉して気密を
保つ手段にはシール用リング部材を使用することが好ま
しい。このシール用リング部材を介し蓋体により加圧密
閉する手段には、上下の蓋体を互いに連結する棒を炉内
を貫通するように渡し、その両側からネジで締める方
法、片方の蓋体に連結棒を固定し、他方の蓋体をネジで
締める方法、上下の蓋体を押さえ枠を炉外に別体として
設け、ネジで締める方法等がある。The upper and lower lids need to have a structure capable of pressurizing and sealing the inside of the heating furnace. It is preferable to use a sealing ring member as a means for maintaining airtightness by pressure sealing. The means for pressurizing and sealing by the lid via the sealing ring member is a method of passing a rod connecting the upper and lower lids so as to penetrate through the furnace, and tightening with screws from both sides of the rod. There are a method of fixing the connecting rod and tightening the other lid with a screw, a method of holding the upper and lower lids as a separate body outside the furnace and tightening with a screw.
【００１３】また、不活性ガス供給管は、従来から運転
時に不活性ガスを供給しているガス出入口をそのまま利
用することができる。不活性ガスの種類としては窒素、
アルゴン、ヘリウム等があり、中でも窒素、アルゴンが
好ましい。不活性ガスの圧力は０．０５〜２kg／cm
2（ゲージ圧）が好ましく、特に０．１〜０．５kg／cm2
（ゲージ圧）が好ましい。Further, as the inert gas supply pipe, the gas inlet / outlet from which the inert gas is conventionally supplied during operation can be used as it is. Nitrogen as the type of inert gas,
There are argon, helium, etc., among which nitrogen and argon are preferable. Inert gas pressure is 0.05-2kg / cm
2 (gauge pressure) is preferred, especially 0.1-0.5 kg / cm 2
(Gauge pressure) is preferable.
【００１４】以下、図面に示す実施例を参照して本発明
を具体的に説明する。図１は本発明の光ファイバ線引き
用加熱炉の休転時保管装置の一例を示す概略図である。
加熱炉１の中にはカーボン製のヒータ２および断熱部材
３が設けられ、加熱炉壁にガス出入口４が開口し、不活
性ガス用開閉弁５および真空用開閉弁６が連結してい
る。The present invention will be described in detail below with reference to the embodiments shown in the drawings. FIG. 1 is a schematic view showing an example of a resting time storage device of a heating furnace for drawing an optical fiber according to the present invention.
A heater 2 and a heat insulating member 3 made of carbon are provided in the heating furnace 1, a gas inlet / outlet 4 is opened in the heating furnace wall, and an inert gas on-off valve 5 and a vacuum on-off valve 6 are connected.
【００１５】加熱炉１の上部にはシール用リング部材１
１を介して加圧密閉用蓋体７が、加熱炉１の下部にはシ
ール用リング部材１1'を介して蓋体８がそれぞれ設けら
れている。下側の蓋体８の中央には、上下蓋体の連結棒
９が突出しており、加熱炉内を通って上側の蓋体７の中
央に設けられた雌ネジにその先端の雄ネジがネジ部１０
で螺止されている。A ring member 1 for sealing is provided on the upper portion of the heating furnace 1.
A lid 7 for pressurizing and sealing is provided via 1 and a lid 8 is provided below the heating furnace 1 via a sealing ring member 11 ′. A connecting rod 9 for the upper and lower lids projects in the center of the lower lid 8, and a male screw at the tip of the female screw provided in the center of the upper lid 7 passes through the heating furnace. Part 10
It is screwed in.
【００１６】この装置を用いて加熱炉の休転時保管をす
るには、上部の蓋体７または下部の蓋体８を回転させて
ネジ部１０を締める必要がある。この蓋体７，８および
シール用リング１１，１1'は円形であることが必要であ
る。図２は本発明の他の実施例を示す概略図である。図
１の装置と異なる点は、下側蓋体８に連結棒９が存在せ
ず、炉の外側から上下蓋体７，８を押える上下蓋体の押
さえ枠９'が別体として設けられ、加圧密閉蓋体押さえ
ネジ１２で締めつけられるようになっている点である。
したがって、この実施例では上下の蓋体７，８を回転さ
せる必要はなく、円形である必要はない。In order to store the heating furnace at rest using this apparatus, it is necessary to rotate the upper lid 7 or the lower lid 8 and tighten the screw portion 10. The lids 7 and 8 and the sealing rings 11 and 11 'need to be circular. FIG. 2 is a schematic view showing another embodiment of the present invention. The difference from the device of FIG. 1 is that the lower cover 8 does not have a connecting rod 9 and a pressing frame 9'of the upper and lower lids for pressing the upper and lower lids 7 and 8 from the outside of the furnace is provided as a separate body. The point is that it can be tightened with the pressure-sealing lid pressing screw 12.
Therefore, in this embodiment, it is not necessary to rotate the upper and lower lids 7 and 8, and it is not necessary that they are circular.
【００１７】[0017]
【実施例】図４に示す光ファイバ線引き装置を使用し、
石英光ファイバにシリコーン樹脂をコーティングして線
引きをした後、図１に示す装置によってアルゴンガスを
０．３５kg／cm2 （ゲージ圧）封入して休転保管した。
一方、比較例として、図３に示す装置によって真空によ
る休転保管を実施した。このようにして線引き運転と休
転保管を３回繰返した結果を、表１に示す。EXAMPLE Using the optical fiber drawing device shown in FIG.
The quartz optical fiber was coated with a silicone resin and drawn, and then argon gas was filled at 0.35 kg / cm 2 (gauge pressure) by the apparatus shown in FIG.
On the other hand, as a comparative example, the apparatus shown in FIG. Table 1 shows the results of repeating the drawing operation and the idle storage three times in this way.
【００１８】[0018]
【表１】 [Table 1]
【００１９】[0019]
【発明の効果】上述したように、本発明によれば次のよ
うな効果を奏することができる。 （１）加熱炉内が加圧状態になって空気の流入がないの
で、ヒータの酸化劣化を防止することができる。 （２）カーボンの酸化による微粉末化がないため、局部
的な弱糸部がなくなり、線引き破断を減少することがで
きる。 （３）加圧用不活性ガスの供給は、運転時の不活性ガス
供給口を利用することができ、設計変更の必要がない。As described above, according to the present invention, the following effects can be obtained. (1) Since the inside of the heating furnace is in a pressurized state and no air flows in, it is possible to prevent oxidative deterioration of the heater. (2) Since there is no pulverization due to oxidation of carbon, local weak yarn portions are eliminated, and wire breakage can be reduced. (3) For supplying the pressurizing inert gas, the inert gas supply port during operation can be used, and there is no need to change the design.
【図１】本発明の光ファイバ線引き用加熱炉の休転時保
管装置の一例を示す概略図である。FIG. 1 is a schematic view showing an example of a resting time storage device of a heating furnace for drawing an optical fiber according to the present invention.
【図２】本発明の光ファイバ線引き用加熱炉の休転時保
管装置の他の例を示す概略図である。FIG. 2 is a schematic view showing another example of a storage device at rest for a heating furnace for drawing an optical fiber according to the present invention.
【図３】従来の光ファイバ線引き用加熱炉の休転時保管
装置の概略図である。FIG. 3 is a schematic view of a conventional idle-time storage device for a heating furnace for drawing an optical fiber.
【図４】光ファイバ線引き装置の概略図である。FIG. 4 is a schematic view of an optical fiber drawing device.
１ 加熱炉 ２ ヒータ ３ 断熱部材 ４ ガス出入口 ５ 不活性ガス開閉弁 ６ 真空開閉弁 ７，８ 加圧密閉用蓋体 ９ 上下蓋体連結
棒 ９' 上部蓋体押さえ枠 １０ 上部蓋体連結
棒ネジ部 １１，１1' シール用リング部材 １２ 加圧密閉用
蓋体押さえネジ １３，１４ 真空用蓋体 １５ 樹脂塗布装
置 １６ 樹脂硬化装置 １７ 巻取機 １８ 光ファイバ母材 １９ 光ファイバ1 heating furnace 2 heater 3 heat insulating member 4 gas inlet / outlet 5 inert gas on / off valve 6 vacuum on / off valve 7,8 lid for pressure sealing 9 upper and lower lid connecting rod 9'upper lid pressing frame 10 upper lid connecting rod screw Part 11, 11 'Sealing ring member 12 Pressurizing and sealing lid pressing screw 13, 14 Vacuum lid 15 Resin coating device 16 Resin curing device 17 Winder 18 Optical fiber base material 19 Optical fiber
Claims (5)
線引き用加熱炉を休転時に保管する際、加熱炉の出入口
部分を加圧密閉可能な蓋体により密閉し、かつ該加熱炉
内部を不活性ガスにより加圧状態にする光ファイバ線引
き用加熱炉の休転時保管方法。1. When a heating furnace for drawing an optical fiber having a built-in carbon heater is stored at rest, the inlet / outlet portion of the heating furnace is closed by a cover capable of pressurizing and the inside of the heating furnace is inert. A method of storing the heating furnace for drawing optical fiber that is pressurized by gas during rest.
圧力を０．０５〜２kg／cm2（ゲージ圧）にする請求項
１に記載の光ファイバ線引き用加熱炉の休転時保管方
法。2. The resting state of the heating furnace for optical fiber drawing according to claim 1, wherein the inert gas pressure inside the heating furnace during resting storage is set to 0.05 to 2 kg / cm 2 (gauge pressure). Storage method.
線引き用加熱炉の出入口部分に、加熱炉内部を加圧密閉
可能にする上下蓋体をそれぞれ配置し、かつ該加熱炉の
壁部に加熱炉内部へ不活性ガスを供給する不活性ガス供
給管を配置した光ファイバ線引き用加熱炉の休転時保管
装置。3. An upper and lower lids for pressurizing and sealing the inside of the heating furnace are arranged at the entrance and exit of the heating furnace for drawing an optical fiber having a built-in carbon heater, and the heating furnace is provided on the wall of the heating furnace. An idle fiber storage device for an optical fiber drawing furnace with an inert gas supply pipe that supplies an inert gas to the inside.
を貫通する連結棒を設けた請求項３に記載の光ファイバ
線引き用加熱炉の休転時保管装置。4. The resting time storage device for a heating furnace for drawing an optical fiber according to claim 3, wherein a connecting rod penetrating the inside of the heating furnace is provided on one of the upper and lower lids.
する連結枠を別体として設けた請求項３または４に記載
の光ファイバ線引き用加熱炉の休転時保管装置。5. The apparatus for storing a resting state of a heating furnace for drawing an optical fiber according to claim 3 or 4, wherein a connecting frame for pressing the upper and lower lids against the entrance and exit of the heating furnace is provided as a separate body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13439095A JPH08325030A (en) | 1995-05-31 | 1995-05-31 | Method for maintaining optical fiber drawing heating furnace in shutdown and device therefor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13439095A JPH08325030A (en) | 1995-05-31 | 1995-05-31 | Method for maintaining optical fiber drawing heating furnace in shutdown and device therefor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH08325030A true JPH08325030A (en) | 1996-12-10 |
Family
ID=15127288
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13439095A Pending JPH08325030A (en) | 1995-05-31 | 1995-05-31 | Method for maintaining optical fiber drawing heating furnace in shutdown and device therefor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH08325030A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000050350A1 (en) * | 1999-02-26 | 2000-08-31 | Corning Incorporated | Method and apparatus for sealing the bottom of a furnace for drawing optical fibre from a preform |
-
1995
- 1995-05-31 JP JP13439095A patent/JPH08325030A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000050350A1 (en) * | 1999-02-26 | 2000-08-31 | Corning Incorporated | Method and apparatus for sealing the bottom of a furnace for drawing optical fibre from a preform |
| US6244099B1 (en) | 1999-02-26 | 2001-06-12 | Corning Incorporated | Draw furnace sealing assembly and method |
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