JPS62162636A - Sintering apparatus for porous preform for optical fiber - Google Patents
Sintering apparatus for porous preform for optical fiberInfo
- Publication number
- JPS62162636A JPS62162636A JP484486A JP484486A JPS62162636A JP S62162636 A JPS62162636 A JP S62162636A JP 484486 A JP484486 A JP 484486A JP 484486 A JP484486 A JP 484486A JP S62162636 A JPS62162636 A JP S62162636A
- Authority
- JP
- Japan
- Prior art keywords
- core tube
- furnace core
- gas
- partition member
- optical fiber
- 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]
- C03B37/01486—Means for supporting, rotating or translating the preforms being formed, e.g. lathes
-
- 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
-
- 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)
- 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)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Glass Melting And Manufacturing (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明は光ファイバ用多孔質母Ｈの焼結装置に係り、特
にＶＡＤ法等で形成された多孔質母材を透明ガラス化す
る焼結装置の炉芯管内圧の安定化に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a sintering device for a porous matrix H for optical fibers, and in particular to a sintering device for transparently vitrifying a porous matrix formed by a VAD method or the like. Related to stabilizing the internal pressure of the furnace core tube of the device.
［従来の技術］
光ファイバ母材の製造において、ＶＡＤ法等により形成
された多孔質母材を透明ガラス化するために従来第４図
に示すような焼結装置が用いられていた。ダなわら、ま
ず引上ロッド１の先端にターゲットボルダ−２が設置さ
れ、このターゲットホルダー２に多孔質母材３がＩｔ積
しているターゲット４を取り付ける。次に、これらを炉
芯管５の内部に挿入した後、炉芯管５下部の吸気口６が
らＨｅガスおよびＣ１２ガスを流し込み、内圧調整弁７
でガス排気孔径を調整することによって炉芯管５の内圧
を所定の値（＋２〜５＃１１１１１２０程度）に保持Ｊ
る。そして、ロッド１を回転しながら一定速度で引き下
げ、炉芯′ｔ２５の外側部に設置されているカーボンヒ
ータ８により多孔質母材３を約１８００℃に加熱して透
明ガラス化された光ファイバ母材９を得ていた。[Prior Art] In the production of optical fiber preforms, a sintering apparatus as shown in FIG. 4 has been conventionally used to turn a porous preform formed by VAD or the like into transparent glass. First, a target boulder 2 is installed at the tip of the pulling rod 1, and a target 4 on which a porous base material 3 is stacked is attached to the target holder 2. Next, after inserting these into the inside of the furnace core tube 5, He gas and C12 gas are poured into the intake port 6 at the bottom of the furnace core tube 5, and the internal pressure regulating valve 7
By adjusting the gas exhaust hole diameter, the internal pressure of the furnace core tube 5 is maintained at a predetermined value (approximately +2 to 5
Ru. Then, the rod 1 is rotated and lowered at a constant speed, and the porous base material 3 is heated to about 1800° C. by the carbon heater 8 installed on the outside of the furnace core 't25, thereby forming a transparent vitrified optical fiber base. Material 9 was obtained.
［発明が解決しようとする問題点］
ところで、多孔質母材３は通常約６０〜１０＃の外径を
有づるが、加熱されて透明ガラス化すると収縮し、製造
された光ファイバ母材９は多孔質母材３の約１０分の１
の大きさとなる。従って、ロッド１により多孔質母材３
が引き下げられて焼結工程が始まると、それに伴って炉
芯管５内のガスの流れ方が経時的に変化しあるいは煙突
効果による部分的な圧力変動が生じやすく、内圧調整弁
７が設けられているにも拘らず、炉芯管５の内圧は変動
し、その大きさを差圧計１０で測定したところほぼ１〜
２ｓ＋ｌｈＯ程度にまで達することがわかった。[Problems to be Solved by the Invention] By the way, the porous preform 3 normally has an outer diameter of about 60 to 10#, but when heated to become transparent vitrified, it contracts, and the manufactured optical fiber preform 9 is about 1/10 of porous base material 3
The size will be . Therefore, the porous base material 3 is
When the pressure is lowered and the sintering process begins, the flow of gas in the furnace core tube 5 changes over time or local pressure fluctuations are likely to occur due to the chimney effect, so an internal pressure regulating valve 7 is provided. Despite this, the internal pressure of the furnace core tube 5 fluctuates, and when its magnitude was measured with a differential pressure gauge 10, it was approximately 1 to 1.
It was found that it reached about 2s+lhO.
この炉芯管内圧は、多孔ｌＬ１母材３内に含有され多孔
質母材３の屈折率分布を決定するドーパントであるＧＣ
０２８１７の蒸発の割合およびＣＩ！２ガスとの反応の
瓜合いを左右するものである。このため、炉芯管内圧が
変動すると多孔質母材３内のＧ（３０２の濃度が変化す
るので、焼結された光ファイバ母材９は長手方向におい
て不均一な屈折率分布を右することになる。This furnace core tube internal pressure is caused by GC, which is a dopant contained in the porous 1L1 base material 3 and determines the refractive index distribution of the porous base material 3.
Evaporation rate and CI of 02817! It influences the coordination of the reactions with the two gases. Therefore, when the internal pressure of the furnace core tube changes, the concentration of G (302) in the porous preform 3 changes, so the sintered optical fiber preform 9 has a non-uniform refractive index distribution in the longitudinal direction. become.
このように従来は炉芯管内圧の変動に伴って光ファイバ
母材の屈折率分布の均一性および再現性が劣化するとい
う問題点があった。As described above, there has been a conventional problem in that the uniformity and reproducibility of the refractive index distribution of the optical fiber preform deteriorate due to fluctuations in the internal pressure of the furnace core tube.
［発明の目的１
本発明の目的は、上記した従来技術の問題点を解間し、
多孔質母材焼結時の炉芯管内圧を安定化して屈折率分布
に乱れのない良質な光ファイバ母材を製造し得る光ファ
イバ用多孔質母材焼結装置を提供することにある。[Objective of the invention 1 The object of the present invention is to solve the problems of the prior art described above,
An object of the present invention is to provide an apparatus for sintering a porous preform for an optical fiber, which can produce a high-quality optical fiber preform without disturbance in the refractive index distribution by stabilizing the internal pressure of a furnace core tube during sintering of the porous preform.
［発明の概要１
上記の目的を達成するために、本発明は、炉芯管内のｌ
Ｉｅ＋Ｃ１２ガス流に対して多孔質母材を保持するター
ゲットより下流側にガス流σを制御づ゛るための仕切部
材を設けたものである。[Summary of the Invention 1 In order to achieve the above object, the present invention provides
A partition member for controlling the gas flow σ is provided downstream from the target holding the porous base material with respect to the Ie+C12 gas flow.
［実施例］
以下、本発明の実施例について添付図面を参照して説明
する。[Examples] Examples of the present invention will be described below with reference to the accompanying drawings.
第１図は本発明の一実施例に係る光ファイバ用多孔質母
材焼結装置の概略構成図である。図中、１は引上ロッド
であり、引上ロッド１の先端に内径１５Ｍ、外径２０＃
ｌＩＩのターゲットホルダー２が設置され、さらにター
ゲットホルダー２の上部に第２図に示すような外径８５
Ｍ、厚さ５ＩＮＲの円盤状の仕切部材１１が設けられて
いる。なお、これら引上ロッド１．ターゲットホルダー
２および仕切部材１１は石英ガラスからなっている。一
方、５は内径９０調、外径９５＃Ｉｍ、長さ１５００ｍ
の石英ガラス製炉芯管で、ガス供給装置（図示せず）に
よって炉芯管下部に設【プられた吸気口６からＩｌｅ＋
α２ガスを導入し、」二部に設けられた内圧調整弁７を
介して排気する。さらに、炉芯管５の下部には内圧の変
動を測定する差圧計１０が、また炉芯管５の外側部には
加熱用のカーボンヒータ８がそれぞれ設置されている。FIG. 1 is a schematic diagram of a porous preform sintering apparatus for optical fibers according to an embodiment of the present invention. In the figure, 1 is a lifting rod, and the tip of the lifting rod 1 has an inner diameter of 15M and an outer diameter of 20mm.
A target holder 2 of III is installed, and an outer diameter 85 as shown in FIG.
A disk-shaped partition member 11 having a diameter of 5 INR and a thickness of 5 INR is provided. In addition, these lifting rods 1. The target holder 2 and the partition member 11 are made of quartz glass. On the other hand, 5 has an inner diameter of 90cm, an outer diameter of 95#Im, and a length of 1500m.
This is a quartz glass furnace core tube.
α2 gas is introduced and exhausted through an internal pressure regulating valve 7 provided in the second part. Further, a differential pressure gauge 10 for measuring fluctuations in internal pressure is installed at the lower part of the furnace core tube 5, and a carbon heater 8 for heating is installed at the outside of the furnace core tube 5.
すなわち、本実施例の焼結装置は第４図の従来例にＪ３
いて、ターゲットボルダ−２の上部に仕切部材１１を設
けたものである。この仕切部４４１１の外径（８５ｍｍ
）は炉芯管５の内径（９０ＩｒＩｎ）より小さく構成さ
れているので、仕切部材１１と炉芯管５の内壁との間に
は一定の大きさの空隙が形成され、炉芯管５の下部から
導入されたｌＩｅ＋ｃＩＬ２ガスはこのわずかな空隙を
通って上部へと流れることとなる。このため、炉芯管５
内のｌｌｅ＋ｃＱ２ガスの流量は多孔質母材の位置ある
いは体積変化に左右されず、仕切部材１１とか芯管５の
内壁との間に形成された空隙によってほぼ一定に保持さ
れる。That is, the sintering apparatus of this embodiment is similar to the conventional example shown in FIG.
A partition member 11 is provided above the target boulder 2. The outer diameter of this partition 4411 (85 mm
) is smaller than the inner diameter (90IrIn) of the furnace core tube 5, so a gap of a certain size is formed between the partition member 11 and the inner wall of the furnace core tube 5, and the lower part of the furnace core tube 5 is The lIe+cIL2 gas introduced from above flows upward through this slight gap. For this reason, the furnace core tube 5
The flow rate of the lle+cQ2 gas inside is not affected by the position or volume change of the porous base material, and is kept almost constant by the gap formed between the partition member 11 and the inner wall of the core tube 5.
次に、本実施例の動作を説明する。Next, the operation of this embodiment will be explained.
まず、多孔質母材３が堆積形成されている外径１５ａｍ
の石英ガラス製ターゲット４をターゲットホルダー２に
取り付け、これらを炉芯管５内に１Φ入する。さらに、
ガス供給装置によって吸気口６がら流ｆｆｉ ７．５〜
１１ ／ｗｉｎのＩｌｅガスおよびＣ１２ガスを炉芯管
５内に送り込むと共に、内圧調整弁７によりガス排気孔
径を調整させて炉芯管５の内圧を＋ ５＃１ＩＩＩｔｈ
Ｏに保持させる。次に、引上ロッド１を約０．５ｒｐｍ
の回転数で回転しながら速度１．５〜５＃／１ｎで引ぎ
下げ、多孔質母材３を炉芯管５の外側部に設置されてい
るカーボンヒータ８によって約１８００℃に加熱して透
明ガラス化し光ファイバ母材９を形成する。First, the outer diameter of the porous base material 3 is 15 am.
A quartz glass target 4 is attached to the target holder 2, and these are inserted into the furnace core tube 5 by 1Φ. moreover,
The gas supply device allows the intake port 6 to flow ffi 7.5~
11/win Ile gas and C12 gas are fed into the furnace core tube 5, and the internal pressure of the furnace core tube 5 is increased by adjusting the gas exhaust hole diameter with the internal pressure regulating valve 7.
Hold O. Next, pull up the pulling rod 1 at about 0.5 rpm.
The porous base material 3 is heated to approximately 1800°C by the carbon heater 8 installed on the outside of the furnace core tube 5. The optical fiber preform 9 is formed into transparent glass.
上記の焼結装置を用いて長さ０４０ｍの多孔質母材を約
１２時間にわたって焼結し、この間の炉芯管５の内圧変
動を差圧計１０によって測定しＩＣところ±０．２１１
１１１１１１２０であった。従って、本実施例の装置で
は従来に比べて炉芯管の内圧変動が極めて小さくなって
いることがわかる。A porous base material with a length of 040 m was sintered for about 12 hours using the above sintering apparatus, and the internal pressure fluctuation of the furnace core tube 5 during this period was measured by the differential pressure gauge 10, and the IC was ±0.211.
It was 11111120. Therefore, it can be seen that in the apparatus of this embodiment, the fluctuation in the internal pressure of the furnace core tube is extremely small compared to the conventional apparatus.
なお、上記実施例では仕切部材１１が円盤状をなして炉
芯管５の内壁との闇に空隙を形成したが、これに限るも
のではなく、例えば第３図のように少イ５くとも１つ以
上の通気孔１２ａが設けられている仕切部材１２を用い
、この通気孔１２ａが上記の空隙の役目を果たすように
構成してもよい。In the above embodiment, the partition member 11 has a disc shape and forms a gap between it and the inner wall of the furnace core tube 5, but the invention is not limited to this. For example, as shown in FIG. The partition member 12 may be provided with one or more ventilation holes 12a, and the ventilation holes 12a may serve as the voids described above.
ざらに、仕切部材をターゲットホルダー２に設置するの
ではなく、中心に引上ロッド１を通す孔が設けられてい
る仕切部材を炉芯管５の内壁に設置してもよい。ただし
、この場合には仕切部材を固定式とすると多孔質母材３
の挿入が妨げられてしまうので、例えば多孔質母材３を
挿入した後に絞り込めるような可変式の仕切部材が必要
となる。In other words, instead of installing the partition member on the target holder 2, a partition member having a hole in the center through which the pulling rod 1 is passed may be installed on the inner wall of the furnace core tube 5. However, in this case, if the partition member is fixed, the porous base material 3
For example, a variable partition member that can be narrowed down after inserting the porous base material 3 is required.
［発明の効果］
以上説明したように本発明によれば次のごとぎ優れた効
果を発揮する。[Effects of the Invention] As explained above, according to the present invention, the following excellent effects are exhibited.
（１） 仕切部材を設Ｇノることによって炉芯管内の
ガス流ｍを一定に保ｌ！することができる。従って、多
孔質母材の位置および体積変化に拘らずに炉芯管の内圧
の安定化が達成される。(1) By installing a partition member, the gas flow inside the furnace core tube can be kept constant! can do. Therefore, the internal pressure of the furnace core tube can be stabilized regardless of the position and volume change of the porous base material.
このため、屈折率分布に乱れがなく、伝送帯域および伝
送娼失等の特性が安定した光ファイバ母材を製造するこ
とができる。Therefore, it is possible to manufacture an optical fiber preform with no disturbance in the refractive index distribution and with stable characteristics such as transmission band and transmission loss.
（ｂ 炉芯管内に仕切部材を設けるだけＣよいので、安
価に実施でさると共に既存設備にも容易に適用でき有用
性が高い。(b) Since it is only necessary to provide a partition member within the furnace core tube, it can be implemented at low cost, and can be easily applied to existing equipment, making it highly useful.
第１図は本発明の光ファイバ用多孔質母材焼結装置の一
実施例を示す概略構成図、第２図は第１図の実施例で用
いられた仕切部材の斜視図、第３図は仕切部材の変形例
を示す斜視図、第４図は従来の焼結装置を示す概略構成
図である。
図中、１は引上ロッド、２はターゲットホルダー、３は
多孔質母材、４はターゲット、５は炉芯管、６は吸気口
、７は内圧調整弁、８はカーボンヒータ、９は光ファイ
バ母材、１０は差圧計、１１Ｊ３よび１２は仕切部材、
１２ａは通気孔である。Fig. 1 is a schematic configuration diagram showing an embodiment of the porous preform sintering device for optical fibers of the present invention, Fig. 2 is a perspective view of a partition member used in the embodiment of Fig. 1, and Fig. 3 4 is a perspective view showing a modified example of the partition member, and FIG. 4 is a schematic configuration diagram showing a conventional sintering apparatus. In the figure, 1 is a pulling rod, 2 is a target holder, 3 is a porous base material, 4 is a target, 5 is a furnace core tube, 6 is an intake port, 7 is an internal pressure regulating valve, 8 is a carbon heater, and 9 is a light Fiber base material, 10 is a differential pressure gauge, 11J3 and 12 are partition members,
12a is a ventilation hole.
Claims (2)
と共に上部より排気しつつ多孔質母材を保持させたター
ゲットを上部から上記ガス流に向って挿入させて焼結す
る装置において、上記炉芯管内に、上記ガス流に対して
上記ターゲットより下流側にガス流量を制御するための
仕切部材が設けられていることを特徴とする光ファイバ
用多孔質母材焼結装置。(1) In a device for sintering by introducing He+Cl_2 gas from the lower part of the furnace core tube and exhausting it from the upper part, a target holding a porous base material is inserted from the upper part toward the gas flow. A porous preform sintering device for an optical fiber, characterized in that a partition member for controlling the gas flow rate is provided in the tube on the downstream side of the target with respect to the gas flow.
ットホルダーに設けられていることを特徴とする特許請
求の範囲第１項記載の光ファイバ用多孔質母材焼結装置
。(2) The apparatus for sintering a porous preform for an optical fiber according to claim 1, wherein the partition member is provided on a target holder that holds the target.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP484486A JPH0629149B2 (en) | 1986-01-13 | 1986-01-13 | Porous base material sintering machine for optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP484486A JPH0629149B2 (en) | 1986-01-13 | 1986-01-13 | Porous base material sintering machine for optical fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62162636A true JPS62162636A (en) | 1987-07-18 |
| JPH0629149B2 JPH0629149B2 (en) | 1994-04-20 |
Family
ID=11594989
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP484486A Expired - Lifetime JPH0629149B2 (en) | 1986-01-13 | 1986-01-13 | Porous base material sintering machine for optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0629149B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62144945U (en) * | 1986-03-07 | 1987-09-12 | ||
| EP0628521A1 (en) * | 1993-06-08 | 1994-12-14 | Sumitomo Electric Industries, Ltd | Apparatus for vitrifying soot preform for optical fiber |
| JP2007145671A (en) * | 2005-11-29 | 2007-06-14 | Sumitomo Electric Ind Ltd | Heating furnace, method for heating glass and method for maintaining heating furnace |
| EP2789590A1 (en) * | 2013-04-10 | 2014-10-15 | Shin-Etsu Chemical Co., Ltd. | Sintering apparatus |
-
1986
- 1986-01-13 JP JP484486A patent/JPH0629149B2/en not_active Expired - Lifetime
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62144945U (en) * | 1986-03-07 | 1987-09-12 | ||
| JPH0711141Y2 (en) * | 1986-03-07 | 1995-03-15 | 古河電気工業株式会社 | Support bar for optical fiber base material manufacturing |
| EP0628521A1 (en) * | 1993-06-08 | 1994-12-14 | Sumitomo Electric Industries, Ltd | Apparatus for vitrifying soot preform for optical fiber |
| US5513983A (en) * | 1993-06-08 | 1996-05-07 | Sumitomo Electric Industries, Inc. | Apparatus for vitrifying soot preform for optical fiber |
| JP2007145671A (en) * | 2005-11-29 | 2007-06-14 | Sumitomo Electric Ind Ltd | Heating furnace, method for heating glass and method for maintaining heating furnace |
| EP2789590A1 (en) * | 2013-04-10 | 2014-10-15 | Shin-Etsu Chemical Co., Ltd. | Sintering apparatus |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0629149B2 (en) | 1994-04-20 |
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