JP3773978B2 - Multi-fiber single-fiber conversion optical fiber with optical fiber connector - Google Patents

Description

【００１７】
ここで、λ1＝Ｌ1／Ｒ、λ2＝Ｌ2／Ｒである。
また、前記薄板バネＳの曲げ応力σは、数式（２）によって示される。
【００１８】
【数２】

【００１９】
薄板バネＳを図７に示すＣ型バネ１９に適用すると、Ｌ1＝０、Ｌ2＝０であり、Ｃ型バネ１９のたわみδ、曲げ応力σは、それぞれ数式（３）、数式（４）によって示される。
【００２０】
【数３】

【００２１】
【数４】

【００２２】
ここで、Ｃ型バネ１９の材質として、例えばＪＩＳ Ｃ１７２０Ｈ／２のバネ材を用いた場合、耐力（最大曲げ応力）σ≧９０ｋｇ／ｍｍ²、曲げ弾性係数Ｅ＝１２００ｋｇ／ｍｍ²である。また、Ｃ型バネ１９の寸法を、内径ｄ＝４．５ｍｍ、板厚ｔ＝０．２３ｍｍ、軸方向長さｂ＝９ｍｍとした場合、Ｃ型バネ１９の直径方向に作用する荷重がＰ＝３．０２ｋｇ（但し、最大値＠ｂ＝９ｍｍ）、たわみがδ＝０．５７３ｍｍ（最大値）となる。
【００２３】
各単心光ファイバ心線１１は、図１および図３に示すように、ナイロン等で樹脂被覆されてφ０．５〜０．９ｍｍの外径を有している。口出し心線部２３は、２５０μｍ以上（好ましくは０．６ｍｍ）の径寸法に形成されており、コード補強が不要な強度を有している。
集合固定部５０は、４本の口出し心線部２３を樹脂等で固定してテープ化した部分であって、４本の口出し心線部２３を光ファイバテープ心線１３の単心線部２５と同等のピッチで一平面に沿って並列している。集合固定部５０から突出する口出し心線部２３の先端に露出する裸ファイバ１２は、図３および図４に示すように、位置決め溝２１の長手方向中央部まで挿入して位置決め調心した状態で、ベース１６と単心線クランプ板２７とに接着剤３１で一体的に接着されている。接着剤３１は、裸ファイバ１２の先端には付着されない。また、各単心光ファイバ心線１１の裸ファイバ１２は、心線収納溝２４、２９の内部に設置した図示しない位置決め手段によって、裸ファイバ１２の先端位置がベース上面１７の長手方向で揃えられている。
【００２４】
集合固定部５０および口出し心線部２３は、ゴム等でチューブ状に形成された弾性体保護具５１に内挿保護されている。弾性体保護具５１の軸方向一端は光ファイバ接続器１５の長手方向端部に固定され、他端は複数本の単心光ファイバ心線１１のナイロン被覆部分１１ａを並行に配列させて集束している。弾性体保護具５１は、各単心光ファイバ心線１１の口出し心線部２３およびこれらの集合固定部５０を収納して保護するとともに、光ファイバ接続器１５の端部から単心光ファイバ心線１１のナイロン被覆部分１１ａ間の口出し心線部２３の湾曲半径を曲げ力に対して規定以上に維持するようになっている。
【００２５】
以下、本発明の多心単心変換用光ファイバ１０の作用および効果を説明する。多心単心変換用光ファイバ１０は、光ファイバ接続器１５の挿入端部（図１から図３中右側）から光ファイバテープ心線１３をテープ心線収納溝２６、３０から挿入して奥側に押し込むだけで、複数本の単心光ファイバ心線１１に変換することができるようになっている。
【００２６】
すなわち、テープ心線収納溝２６、３０に挿入した光ファイバテープ心線１３は、予め端部に露出させておいた裸ファイバ１４が心線収納溝２４を介して位置決め溝２１に導かれて、調心ピース２０の中央部においてそれぞれ単心光ファイバ心線１１の裸ファイバ１２と突き合わせ接続される。この時、光ファイバテープ心線１３の裸ファイバ１４は、互いの先端位置を揃えておく。こうすることにより、光ファイバテープ心線１３をテープ心線収納溝２６、３０からその奥側に押し込むだけで、すべての裸ファイバ１４が単心光ファイバ心線１１の裸ファイバ１２と同時に突き合わされ、しかも、突き合わせ時に裸ファイバ１４間での突き合わせ力のばらつきを防止することができる。
光ファイバテープ心線１３の被覆部分１３ａは、テープ心線収納溝２６、３０内に収納されて、ベース１６と押さえ蓋１８との間にクランプされた時に、光ファイバテープ心線１３に作用する引張力等に対する十分な引き留め力を発揮するようになっている。
【００２７】
光ファイバテープ心線１３のテープ心線収納溝２６、３０への挿入時には、図５に示すように、挿入端部側にある第３の領域１９ｃと、第２の領域１９ｂの第３の領域１９ｃ側とにある開口部材挿入口３５に開口部材３６を挿入してＣ型バネ１９によるクランプ力を予め解除しておく。この時、ベース１６とテープクランプ板２８との間のクランプ力が解除されてテープ心線収納溝２６、３０への光ファイバテープ心線１３の挿入が可能となるが、ベース１６と単心線クランプ板２７との間は接着剤３１によって固定状態が維持される。
【００２８】
光ファイバテープ心線１３と単心光ファイバ心線１１との突き合わせ接続が完了したら、開口部材３６を引き抜く。こうすることにより、Ｃ型バネ１９によるクランプ力が付与されて、ベース１６とテープクランプ板２８との間に光ファイバテープ心線１３がクランプされる。この時、単心光ファイバ心線１１と光ファイバテープ心線１３の双方の裸ファイバ１２、１４の突き合わせ部分もベース１６とテープクランプ板２８とによってクランプされるので、突き合わせ状態が安定に保持される。
また、Ｃ型バネ１９のクランプ力を再度解除することにより、クランプした光ファイバテープ心線１３が光ファイバ接続器１５から引き抜き可能になるので、接続切替を簡便に行うことができる。
【００２９】
多心単心変換用光ファイバ１０を組み立てるには、まず集合固定部５０を形成して各単心光ファイバ心線１１のナイロン被覆を口出しして露出させた口出し心線部２３を集合固定してテープ化するとともに、さらに口出し心線部２３の集合固定部５０から突出する先端に露出させた裸ファイバ１２を位置決め溝２１に位置決めして各単心光ファイバ心線１１をベース１６と押さえ蓋１８との間に挟み込み、接着剤注入孔３２を介して接着剤３１を注入した後、一体化したベース１６および押さえ蓋１８をＣ型バネ１９に内挿して接着剤３１を固化させるとともに、弾性保護具５１を装着する。
完成した多心単心変換用光ファイバ１０は、現場に搬入してテープ心線収納溝２６、３０から光ファイバテープ心線１３の裸ファイバ１４を光ファイバ接続器１５内に挿入するだけで、光ファイバテープ心線１３と単心光ファイバ心線１１とを一括して光接続することができる。したがって、多心単心変換用光ファイバ１０は、現場において容易かつ高精度に光ファイバテープ心線１３と単心光ファイバ心線１１とを光接続することができる。
【００３０】
なお、光ファイバ接続器１５のクランプ力が十分であれば、単心光ファイバ心線１１の接着固定を省略することもできる。また、単心光ファイバ心線１１の図示しない反対側の端部（光ファイバ接続器１５から放射状に延びる端部）は、単心用ＭＴコネクタで他の単心光ファイバと接続可能に成端してもよい。
【００３１】
したがって、本発明の多心単心変換用光ファイバ１０によれば、屋外での組み立てや単心光ファイバ心線１１と光ファイバテープ心線１３との光接続作業を容易に行うことができ、しかも、光ファイバ接続器１５に光ファイバテープ心線１３を挿入するだけで光ファイバテープ心線１３を単心光ファイバ心線１１と簡単に接続することができるので、作業現場での光ファイバテープ心線１３の単心変換を簡便に行うことができる。その結果、例えば、架空光ファイバケーブルのクロージャ等での高所作業においても、高い作業能率を確保することができる。また、突き合わせ接続した光ファイバテープ心線１３と単心光ファイバ心線１１とを光ファイバ接続器１５でクランプする構造なので、従来のＭＴコネクタで成端する場合に比べて部品点数が少なくて済み、組み立ての工数を少なくでき、しかも裸ファイバ１２、１４の調心精度が簡単に得られるとともに、コストを低減することができる。
【００３２】
特に、前記多心単心変換用光ファイバ１０は、光ファイバテープ心線１３の単心線部２５と径寸法の等しい単心光ファイバ心線１１の口出し心線部２３を、集合固定部５０によって前記単心線部２５と同等のピッチで配列させて、光ファイバ接続器１５内に固定するので、光ファイバ接続器１５の構造を単純にすることができ、低コスト化が容易である。また、裸ファイバ１２、１４の調心位置決めや、各裸ファイバ１２、１４の先端位置揃え等が容易になり、しかも、双方の裸ファイバ１２、１４の接続精度を向上することができる。
【００３３】
さらに、前記多心単心変換用光ファイバ１０によれば、集合固定部５０および該集合固定部５０近傍の口出し心線部２３を弾性体保護具５１で保護して、単心光ファイバ心線１１の一端部全体の湾曲半径を曲げ力に対して規定以上に維持するようにしたので、口出し心線部２３をコード化すること無く簡便に保護することができるとともに、単心光ファイバ心線１１の光伝送性能を常時安定に維持することができる。
【００３４】
加えて、前記多心単心変換用光ファイバ１０では、光ファイバ接続器１５に複数本の単心光ファイバ心線１１をテープ化して固定するようにしたので、従来の光ファイバテープ心線から分岐した光ファイバ心線に比して太径の光ファイバ心線を使用することが可能となり、２５０μｍ以上の径の単心光ファイバ心線１１を使用することによりコード化を不要としたので、多心単心変換用光ファイバ１０の組み立て工数を一層減少することができる。
【００３５】
なお、多心光ファイバとしては、光ファイバテープ心線以外であってもよい。調心機構としては、マイクロキャピラリーが設置されたＶ溝またはＶ溝以外の位置決め溝や、精密ロッド、精密ボールを用いた調心構造の適用も可能である。
【００３６】
【発明の効果】
以上説明したように、本発明の光ファイバ接続器付きの多心単心変換用光ファイバによれば、複数本の単心光ファイバと、これら単心光ファイバの一端部を多心光ファイバを構成する複数本の光ファイバの配列に対応したピッチで並列させて集合固定する集合固定部と、該集合固定部から突出した各単心光ファイバの突き合わせ端部が固定され、該突き合わせ端部と多心光ファイバの光ファイバとを突き合わせ接続する光ファイバ接続器とを具備してなり、前記光ファイバ接続器は、ベースと、該ベース上面上に装着されることにより単心光ファイバに突き合わせ接続した多心光ファイバをベースとの間にクランプして突き合わせ状態を保持する押さえ蓋と、ベースと押さえ蓋とにクランプ力を付与および解除するクランプ手段と、ベースと押さえ蓋との間において単心光ファイバの突き合わせ端部および多心光ファイバを突き合わせ接続可能に位置決め調心する調心機構とを具備し、互いに等しいピッチで配列した多心光ファイバの光ファイバと単心光ファイバとを光ファイバ接続器で接続するようにしたので、光ファイバ接続器の構造が単純になって低コスト化が容易になるとともに、単心光ファイバと多心光ファイバの光ファイバとの接続精度を向上することができるといった優れた効果を奏する。
さらに、集合固定部および該集合固定部近傍の単心光ファイバを弾性体保護具で被覆して、単心光ファイバの口出し心線部の湾曲半径を維持するようにしたので、集合固定部および該集合固定部近傍の単心光ファイバをコード化すること無く簡便に保護することができるとともに、単心光ファイバの光伝送性能を安定に維持することができるといった優れた効果を奏する。
【００３７】
請求項２記載の光ファイバ接続器付きの多心単心変換用光ファイバでは、請求項１記載の光ファイバ接続器付きの多心単心変換用光ファイバにおいて、多心光ファイバ側の光ファイバ心線と単心光ファイバの口出し心線部とが、２５０μｍ以上の同一の径寸法を有するので、光ファイバ接続器の構造を一層単純化することができ、低コスト化や接続精度一層向上する。
【図面の簡単な説明】
【図１】 本発明の光ファイバ接続器付きの多心単心変換用光ファイバの実施の形態を示す斜視図である。
【図２】 本発明の光ファイバ接続器付きの多心単心変換用光ファイバの実施の形態の作用を示す全体略図である。
【図３】 本発明の光ファイバ接続器付きの多心単心変換用光ファイバの実施の形態を示す正断面図である。
【図４】 本発明の光ファイバ接続器付きの多心単心変換用光ファイバの実施の形態を示す図であって、ベースを示す平面図である。
【図５】 本発明の光ファイバ接続器付きの多心単心変換用光ファイバの実施の形態の作用を示す斜視図である。
【図６】 薄板バネにおける荷重に対するたわみおよび曲げ応力を示すモデル図である。
【図７】 本発明の光ファイバ接続器の実施の形態を示す図であって、Ｃ型バネにおける荷重に対するたわみおよび曲げ応力を示すモデル図である。
【図８】 従来例の光ファイバ接続器付きの多心単心変換用光ファイバを示す全体略図である。
【符号の説明】
１０…光ファイバ接続器付きの多心単心変換用光ファイバ、１１…単心光ファイバ（単心光ファイバ心線）、１２…突き合わせ端部（裸ファイバ）、１３…多心光ファイバ（光ファイバテープ心線）、１４…光ファイバ（裸ファイバ）、１５…光ファイバ接続器、１６…ベース、１７…ベース上面、１８…押さえ蓋、１９…クランプ手段（Ｃ型バネ）、２１…調心機構（位置決め溝）、２３…光ファイバ心線（口出し心線部）、２５…光ファイバ心線（単心線部）、５０…集合固定部、５１…弾性体保護具。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a multi-core single-core conversion optical fiber with an optical fiber connector for branching a multi-core optical fiber into a plurality of single-core optical fibers.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a multi-core single-core conversion optical fiber that branches a multi-core optical fiber into a plurality of single-core optical fibers, for example, as shown in FIG. 8, one end of a four-core or eight-core optical fiber ribbon 1 The optical connector 2 is attached to the optical fiber tape 3 so that it can be optically connected to the optical fiber tape 3, and the optical fiber tape core 1 is cut from the middle of the optical fiber tape core 1 to the single optical fiber core 5 through the reinforcing branch 4 The optical fiber core 5 can be optically connected to other optical fiber cores by attaching a single-fiber optical connector 6 to the end of the optical fiber core 5. Terminated. Moreover, since the optical fiber core wire 5 is a wire branched from the optical fiber tape core wire 1, the diameter is usually 250 μm or less if the coating of the optical fiber tape core wire 1 is removed. And reinforce.
[0003]
[Problems to be solved by the invention]
By the way, in the optical fiber connection work of the aerial closure, there are many cases where it is necessary to take out the tape core wire from the optical fiber cable and convert the tape core wire into a single core. In this case, a multi-fiber single-fiber conversion optical fiber with MT (Mechanically Tranferable) connectors at both ends, which is manufactured in the factory in advance, is prepared, and the multi-fiber single-fiber conversion optical fiber is provided at the end of the tape core wire. It is necessary to connect the MT connectors on the multi-core side of the field. When terminating the optical fiber tape core wire 1 for multi-fiber single-core conversion in such a manner that the connection can be switched, it is necessary to attach an MT connector. Since various tools are required for the assembly, on-site assembly requires a large number of work steps, and the work may be difficult.
[0004]
The present invention has been made in view of the above-described problems. There is no connection work of the MT connector to the multi-core optical fiber drawn out from the optical fiber cable, the assembly is easy, and the connection switching can be easily performed. An object of the present invention is to provide an optical fiber for multi-core single-core conversion with an optical fiber connector that has improved versatility during on-site connection work and can be easily connected to a multi-fiber optical fiber.
[0005]
[Means for Solving the Problems]
A multi-fiber single-fiber conversion optical fiber with an optical fiber connector according to claim 1, wherein a plurality of single-core optical fibers having a lead-off core portion removed from a coating on one end thereof, and these single-core optical fibers An assembly fixing portion that fixes the lead core portions in parallel with a pitch corresponding to the arrangement of a plurality of optical fibers constituting the multi-core optical fiber, and each single-core optical fiber protruding from the assembly fixing portion. An abutting end is fixed, and comprises an optical fiber connector for abutting and connecting the abutting end and an optical fiber of a multi-core optical fiber. The optical fiber connector is provided on a base and an upper surface of the base. By attaching the multi-fiber optical fiber that is butt-connected to the single-core optical fiber and clamping it between the base and holding the butt, a clamping force is applied to the base and the cover lid. Comprising a clamping means for releasing, a single-core optical fiber of the butt end and multiconductor tone connected positionable aligning butt optical fibers mechanism between the base and the pressing lid, one end of the set fixed part Is housed in a collective fixing portion receiving groove formed at one end in the longitudinal direction of the upper surface of the base, and the lead core portion is disposed between the other end of the collective fixing portion and the coated portion of the single-core optical fiber. The exposed and fixed single-core optical fiber in the vicinity of the fixed assembly portion and the fixed assembly portion is covered with an elastic body protector so as to maintain the radius of curvature of the lead-out core portion of the single-core optical fiber, and One end in the axial direction of the elastic body protector is fixed to the outer peripheral surface of the longitudinal end of the base and the presser lid of the optical fiber connector, and the other end of the elastic body protector is covered with a plurality of single-core optical fibers. Parts in parallel It focused by column and that it has a space between the inner surface of the lead-out core wire portion and the elastic body protector as solutions of the problems.
[0006]
3. A multi-core single-core conversion optical fiber with an optical fiber connector according to claim 2, wherein said multi-fiber single-fiber conversion optical fiber with optical fiber connector is an optical fiber on the multi-core optical fiber side. The means for solving the above-mentioned problems is that the core wire and the lead core portion of the single-core optical fiber have the same diameter dimension of 250 μm or more.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of an optical fiber for multi-core single-core conversion with an optical fiber connector according to the present invention will be described below with reference to FIGS.
Reference numeral 10 in the figure denotes a multi-fiber single-core conversion optical fiber (hereinafter referred to as multi-fiber single-core conversion optical fiber) with an optical fiber connector according to the present embodiment. As shown in FIGS. 1 to 3, the multi-fiber single-core conversion optical fiber 10 includes four single-core optical fibers 11 (single-core optical fibers) and one end of the single-core optical fibers 11. An assembly fixing portion 50 that aggregates and fixes the lead core portion 23 that is exposed by being exposed from the fiber, and the bare fiber 12 (butting end) that is exposed from the tip of the lead core portion 23 that protrudes from the assembly fixing portion 50 And an optical fiber connector 15 that butt-connects the bare fiber 14 (optical fiber) derived from the four-fiber optical fiber ribbon 13 (multi-fiber optical fiber).
[0009]
The optical fiber connector 15 is mounted on a base 16 and an upper surface 17 (see FIG. 3) of the base 16 so that the single-core optical fiber core 11 and the optical fiber tape core 13 that are butt-connected are connected. A pressing lid 18 that clamps between the base 16 and holds the butted state, and a C-shaped spring 19 as a clamping means that applies and releases a clamping force to the base 16 and the pressing lid 18 are provided.
[0010]
The base 16 and the presser lid 18 are rod-shaped members that form a split cylinder by overlapping each other and are semicircular in cross section.
As shown in FIGS. 3 and 4, the bare fibers 12 of both the single-core optical fiber core 11 and the optical fiber ribbon 13 are disposed in the center portion of the base upper surface 17 in the longitudinal direction (left-right direction in FIGS. 3 and 4). , 14 are mounted on the alignment piece 20 for positioning and aligning and connecting each other. On the upper surface of the aligning piece 20, four positioning grooves 21 which are V grooves penetrating along the longitudinal direction of the base upper surface 17 are formed in parallel. These positioning grooves 21 function as an aligning mechanism for aligning and positioning the optical fiber tape core wire 13 with respect to the single-core optical fiber core wire 11 between the base 16 and the presser lid 18 so that they can be connected to each other. .
[0011]
At one end of the base upper surface 17 in the longitudinal direction (left side in FIGS. 3 and 4), a set fixing portion receiving groove 50 a for storing the end of the set fixing portion 50 and the lead of each single-core optical fiber 11 protruding from the set fixing portion 50. A plurality of core wire storage grooves 24, which are V grooves for storing the core wire portions 23 in parallel, are formed in parallel. At the other end in the longitudinal direction of the base upper surface 17, a tape core wire housing groove 26 for housing the covering portion 13 a of the optical fiber tape core wire 13 and an end portion of the optical fiber tape core wire 13 are exposed and exposed. A plurality of V-shaped core wire storage grooves 24 for storing the wire portions 25 are formed in parallel. The single-core part 25 is a single-core part formed by coating each bare fiber 14 with a coating material. The bare fiber 14 is a portion from which the coating of the tip of the single core wire portion 25 is removed.
The lead core part 23 and the single core part 25 are both aligned to 250 μm. The core wire storage grooves 24 at both ends in the longitudinal direction of the base upper surface 17 are formed with the same shape and the same pitch. Further, the positioning groove 21 of the aligning piece 20 is shallower than these core wire storage grooves 24 and is precisely formed. The alignment axes of the positioning grooves 21 and the core wire storing grooves 24 at both ends of the base upper surface 17 corresponding to the positioning grooves 21 are on the same straight line. Accordingly, the bare fibers 12 and 14 inserted from the respective core wire storage grooves 24 naturally enter the positioning groove 21 by being pushed toward the center portion of the alignment piece 20.
[0012]
As shown in FIG. 3, the pressing lid 18 is composed of two members: a single-core wire clamp plate 27 attached to one end portion of the base upper surface 17 and a tape clamp plate 28 attached to the other end portion of the base upper surface 17. Has been. A core wire storage groove 29 for storing and clamping the lead core portion 23 of the single-core optical fiber core wire 11 in a portion of the single core wire clamp plate 27 and the tape clamp plate 28 facing the core wire storage groove 24. Is formed. In the portion of the single core wire clamp plate 27 and the tape clamp plate 28 facing the assembly fixing portion storage groove 50a or the tape core wire storage groove 26, the assembly fixing portion 50 or the covering portion 13a of the optical fiber tape core wire 13 is stored. An assembly fixing portion storage groove 50b or a tape core wire storage groove 30 is formed.
An adhesive injection hole 32 for injecting an adhesive 31 (see FIG. 4) is formed between the base 16 and the single-core clamp plate 27 at the center of the single-core clamp plate 27.
The portions other than the core wire storage groove 29, the tape core wire storage groove 30, the adhesive injection hole 32, and the assembly fixing portion storage groove 50b of the single core wire clamp plate 27 and the tape clamp plate 28 are stored in the positioning groove 21 and the core wire storage. A pressing surface is formed to press the bare fibers 12 and 14 and the single core wire portion 25 disposed in the groove 24 toward the deep portions of the positioning groove 21 and the core wire storage groove 24.
[0013]
As shown in FIG. 1, the C-type spring 19 is attached to the outside of the base 16 and the presser lid 18 that are overlapped with each other, and the base 16 and the presser lid 18 are tightened in a direction in which they are pressed against each other to maintain an integrated state. It is supposed to be. Further, the opening 33 that opens to the side surface of the C-shaped spring 19 coincides with the boundary between the base 16 and the presser lid 18 that are overlapped with each other. At two locations in the longitudinal direction of the opening 33, slits 34 extending along the circumferential direction of the C-shaped spring 19 are formed. These slits 34 are opened over substantially the entire circumference in the circumferential direction of the C-shaped spring 19 except for a coupling portion (not shown) located on the opposite side of the opening 33 in the diameter direction of the C-shaped spring 19. The three regions 19a, 19b and 19c are divided into three regions 19a, 19b and 19c which can be deformed independently.
[0014]
At four positions in the longitudinal direction of the opening 33, an opening member insertion opening 35 is formed by expanding the opening 33. As shown in FIG. 5, each opening member insertion port 35 inserts an opening member 36 from the outside to release the clamping force of the optical fibers 11 and 13 acting between the base 16 and the pressing lid 18. Is. The opening member insertion ports 35 are distributed and arranged in the first to third regions 19a, 19b, 19c defined by the slits 34 of the C-shaped spring 19, and are located at both ends in the longitudinal direction. One region is formed in each of the regions 19a and 19c, and two regions are formed in the second region 19b located in the center.
[0015]
The C-type spring 19 is made of a material such as beryllium copper. In the case of beryllium copper, it may be one that has been subjected to age hardening treatment after molding into a target shape, or one that has been coated with a fluororesin or the like after heat treatment.
The pressing force of the C-type spring 19 that presses the interior base 16 and the pressing lid 18 in a direction in which they are pressed against each other is set by the material and shape of the C-type spring 19.
That is, for example, as shown in FIG. 6, in the case of a substantially U-shaped thin plate spring S, the load acting between both ends is P, the bending radius is R, the spring plate thickness is t, and the spring length is b. Then, the deflection δ between both ends is expressed by Equation (1).
[0016]
[Expression 1]

[0017]
Here, λ1 = L1 / R and λ2 = L2 / R.
Further, the bending stress σ of the thin leaf spring S is expressed by the mathematical formula (2).
[0018]
[Expression 2]

[0019]
When the thin plate spring S is applied to the C-type spring 19 shown in FIG. 7, L1 = 0 and L2 = 0, and the deflection δ and the bending stress σ of the C-type spring 19 are expressed by Equations (3) and (4), respectively. Indicated.
[0020]
[Equation 3]

[0021]
[Expression 4]

[0022]
Here, when the spring material of JIS C1720H / 2 is used as the material of the C-type spring 19, for example, the proof stress (maximum bending stress) σ ≧ 90 kg / mm ² and the bending elastic modulus E = 1200 kg / mm ² . When the dimensions of the C-type spring 19 are an inner diameter d = 4.5 mm, a plate thickness t = 0.23 mm, and an axial length b = 9 mm, the load acting in the diameter direction of the C-type spring 19 is P = 3.02 kg (however, the maximum value @ b = 9 mm), and the deflection is δ = 0.573 mm (maximum value).
[0023]
As shown in FIGS. 1 and 3, each single-core optical fiber core wire 11 is coated with a resin such as nylon and has an outer diameter of φ0.5 to 0.9 mm. The lead-out core part 23 is formed in a diameter of 250 μm or more (preferably 0.6 mm), and has a strength that does not require cord reinforcement.
The assembly fixing portion 50 is a portion obtained by fixing the four lead core portions 23 with a resin or the like, and forming the four lead core portions 23 into a single core portion 25 of the optical fiber tape core wire 13. Are parallel along one plane at the same pitch. As shown in FIGS. 3 and 4, the bare fiber 12 exposed at the tip of the lead core portion 23 protruding from the assembly fixing portion 50 is inserted to the center in the longitudinal direction of the positioning groove 21 and positioned and aligned. The base 16 and the single-core wire clamp plate 27 are integrally bonded with an adhesive 31. The adhesive 31 is not attached to the tip of the bare fiber 12. Further, the bare fiber 12 of each single-core optical fiber core 11 is aligned in the longitudinal direction of the base upper surface 17 by positioning means (not shown) installed inside the core wire housing grooves 24 and 29. ing.
[0024]
The collective fixing part 50 and the lead-out core part 23 are internally protected by an elastic body protector 51 formed in a tube shape with rubber or the like. One end in the axial direction of the elastic body protector 51 is fixed to the end in the longitudinal direction of the optical fiber connector 15, and the other end is focused by arranging the nylon-coated portions 11 a of the single-core optical fiber cores 11 in parallel. ing. The elastic body protector 51 houses and protects the lead-out core portion 23 of each single-core optical fiber core wire 11 and the assembly fixing portion 50, and the single-core optical fiber core from the end portion of the optical fiber connector 15. The bending radius of the lead-out core portion 23 between the nylon-coated portions 11a of the wire 11 is maintained more than specified with respect to the bending force.
[0025]
The operation and effect of the multi-fiber single-core conversion optical fiber 10 of the present invention will be described below. The optical fiber 10 for multi-fiber single-core conversion is inserted by inserting the optical fiber tape core 13 from the insertion end (right side in FIGS. 1 to 3) of the optical fiber connector 15 through the tape core wire receiving grooves 26 and 30. It can be converted into a plurality of single-core optical fibers 11 simply by pushing them to the side.
[0026]
That is, the optical fiber tape core wire 13 inserted into the tape core wire storage grooves 26 and 30 has the bare fiber 14 previously exposed at the end portion thereof guided to the positioning groove 21 via the core wire storage groove 24, At the center portion of the aligning piece 20, each is connected to the bare fiber 12 of the single-core optical fiber 11. At this time, the bare fibers 14 of the optical fiber ribbon 13 are aligned at the tip positions. By doing this, all the bare fibers 14 are abutted simultaneously with the bare fibers 12 of the single-core optical fiber core 11 simply by pushing the optical fiber tape core 13 into the inner side of the tape core housing grooves 26, 30. Moreover, it is possible to prevent variations in the butting force between the bare fibers 14 at the time of butting.
The covering portion 13a of the optical fiber ribbon 13 acts on the optical fiber ribbon 13 when it is accommodated in the tape strands 26 and 30 and clamped between the base 16 and the pressing lid 18. A sufficient retaining force against a tensile force or the like is exhibited.
[0027]
As shown in FIG. 5, when the optical fiber tape core wire 13 is inserted into the tape core wire storage grooves 26, 30, the third region 19c on the insertion end side and the third region of the second region 19b are provided. The opening member 36 is inserted into the opening member insertion port 35 on the 19c side, and the clamping force by the C-shaped spring 19 is released in advance. At this time, the clamping force between the base 16 and the tape clamp plate 28 is released, and the optical fiber tape core wire 13 can be inserted into the tape core wire receiving grooves 26, 30. A fixed state is maintained by the adhesive 31 between the clamp plate 27 and the clamp plate 27.
[0028]
When the butt connection between the optical fiber ribbon 13 and the single-fiber ribbon 11 is completed, the opening member 36 is pulled out. By doing so, a clamping force is applied by the C-shaped spring 19, and the optical fiber ribbon 13 is clamped between the base 16 and the tape clamp plate 28. At this time, the butted portions of the bare fibers 12 and 14 of both the single optical fiber core 11 and the optical fiber ribbon 13 are also clamped by the base 16 and the tape clamp plate 28, so that the butted state is stably maintained. The
Further, by releasing the clamping force of the C-shaped spring 19 again, the clamped optical fiber tape core wire 13 can be pulled out from the optical fiber connector 15, so that connection switching can be performed easily.
[0029]
In order to assemble the multi-fiber single-core conversion optical fiber 10, first, the assembly fixing portion 50 is formed, and the lead-out core portion 23 exposed by exposing the nylon coating of each single-core optical fiber core wire 11 is assembled and fixed. In addition, the bare fiber 12 exposed at the tip protruding from the assembly fixing portion 50 of the lead-out core portion 23 is positioned in the positioning groove 21 so that each single-core optical fiber core 11 is fixed to the base 16 and the pressing lid. 18, the adhesive 31 is injected through the adhesive injection hole 32, and the integrated base 16 and presser lid 18 are inserted into the C-shaped spring 19 to solidify the adhesive 31 and elastic. Wear protective equipment 51.
The completed multi-fiber single-core conversion optical fiber 10 is simply brought into the field and the bare fiber 14 of the optical fiber tape core 13 is inserted into the optical fiber connector 15 from the tape core housing grooves 26 and 30. The optical fiber ribbon 13 and the single-core optical fiber 11 can be optically connected together. Therefore, the multi-fiber single-core conversion optical fiber 10 can optically connect the optical fiber tape core wire 13 and the single-core optical fiber core wire 11 easily and with high precision in the field.
[0030]
If the clamping force of the optical fiber connector 15 is sufficient, the adhesive fixing of the single-core optical fiber core wire 11 can be omitted. The other end (the end extending radially from the optical fiber connector 15) of the single-core optical fiber core 11 (not shown) is terminated with a single-fiber MT connector so that it can be connected to another single-core optical fiber. May be.
[0031]
Therefore, according to the multi-fiber single-core conversion optical fiber 10 of the present invention, it is possible to easily perform outdoor assembly and optical connection work of the single-core optical fiber core wire 11 and the optical fiber tape core wire 13, Moreover, the optical fiber tape core 13 can be easily connected to the single-core optical fiber core 11 simply by inserting the optical fiber tape core 13 into the optical fiber connector 15. Single-core conversion of the core wire 13 can be performed easily. As a result, for example, high work efficiency can be ensured even in high place work such as with an overhead optical fiber cable closure. In addition, since the optical fiber tape core 13 and the single optical fiber core 11 that are butt-connected are clamped by the optical fiber connector 15, the number of parts can be reduced as compared with the case of termination with a conventional MT connector. The number of assembly steps can be reduced, and the alignment accuracy of the bare fibers 12 and 14 can be easily obtained, and the cost can be reduced.
[0032]
In particular, the multi-core single-core conversion optical fiber 10 includes a single core portion 25 of the single-core optical fiber core 11 having the same diameter as the single-core portion 25 of the optical fiber tape core 13 and an assembly fixing portion 50. Thus, the optical fiber connector 15 is arranged at a pitch equivalent to that of the single-core wire portion 25 and fixed in the optical fiber connector 15, so that the structure of the optical fiber connector 15 can be simplified and the cost can be easily reduced. In addition, the alignment of the bare fibers 12 and 14 and the alignment of the tips of the bare fibers 12 and 14 can be facilitated, and the connection accuracy between the bare fibers 12 and 14 can be improved.
[0033]
Furthermore, according to the multi-fiber single-core conversion optical fiber 10, the assembly fixing portion 50 and the lead-out core portion 23 in the vicinity of the assembly fixing portion 50 are protected by the elastic body protector 51, and the single-core optical fiber core wire is protected. Since the bending radius of the entire one end portion of 11 is maintained more than specified with respect to the bending force, the lead core portion 23 can be easily protected without coding, and a single-core optical fiber core wire can be protected. 11 optical transmission performance can always be maintained stably.
[0034]
In addition, in the multi-fiber single-core conversion optical fiber 10, a plurality of single-core optical fibers 11 are taped and fixed to the optical fiber connector 15. Since it becomes possible to use a large-diameter optical fiber core as compared with a branched optical fiber core, and the use of the single-core optical fiber core 11 having a diameter of 250 μm or more eliminates the need for coding. The number of steps for assembling the multi-fiber single-core conversion optical fiber 10 can be further reduced.
[0035]
The multi-core optical fiber may be other than the optical fiber tape. As the aligning mechanism, it is also possible to apply a aligning structure using a positioning groove other than the V groove or the V groove provided with the microcapillary, a precision rod, and a precision ball.
[0036]
【The invention's effect】
As described above, according to the multi-fiber single-fiber conversion optical fiber with an optical fiber connector of the present invention, a plurality of single-core optical fibers and one end of each single-core optical fiber are connected to the multi-core optical fiber. An assembly fixing portion that is assembled and fixed in parallel at a pitch corresponding to the arrangement of a plurality of optical fibers to be configured, and a butt end portion of each single-core optical fiber that protrudes from the assembly fixing portion is fixed, and the butt end portion An optical fiber connector for butt connection with an optical fiber of a multi-core optical fiber, the optical fiber connector being butt-connected to a single-core optical fiber by being mounted on the upper surface of the base A holding lid that clamps the multi-core optical fiber between the base and the base, a clamping means that applies and releases a clamping force to the base and the pressing lid, and a base. An optical fiber of a multi-core optical fiber arranged at equal pitches, the butt end of the single-fiber optical fiber and an alignment mechanism for positioning the multi-fiber optical fiber so as to be able to butt-connect to each other. Since the optical fiber connector is used to connect the single-fiber optical fiber, the structure of the optical fiber connector is simplified and the cost is easily reduced. There is an excellent effect that the connection accuracy can be improved.
Further, the assembly fixing portion and the single-core optical fiber in the vicinity of the assembly fixing portion are covered with an elastic body protector so as to maintain the bending radius of the lead core portion of the single-core optical fiber. The single-core optical fiber near the assembly fixing portion can be easily protected without coding, and the optical transmission performance of the single-core optical fiber can be stably maintained.
[0037]
3. A multi-core single-core conversion optical fiber with an optical fiber connector according to claim 2, wherein said multi-fiber single-fiber conversion optical fiber with optical fiber connector is an optical fiber on the multi-core optical fiber side. Since the core wire and the lead core portion of the single-core optical fiber have the same diameter dimension of 250 μm or more, the structure of the optical fiber connector can be further simplified, and the cost and the connection accuracy are further improved. .
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of an optical fiber for multi-core single-core conversion with an optical fiber connector of the present invention.
FIG. 2 is an overall schematic diagram showing the operation of an embodiment of a multi-fiber single-core conversion optical fiber with an optical fiber connector of the present invention.
FIG. 3 is a front sectional view showing an embodiment of an optical fiber for multi-core single-core conversion with an optical fiber connector of the present invention.
FIG. 4 is a diagram showing an embodiment of an optical fiber for multi-core single-core conversion with an optical fiber connector of the present invention, and is a plan view showing a base.
FIG. 5 is a perspective view showing the operation of the embodiment of the multi-fiber single-core conversion optical fiber with an optical fiber connector of the present invention.
FIG. 6 is a model diagram showing deflection and bending stress with respect to load in a thin plate spring.
FIG. 7 is a diagram showing an embodiment of the optical fiber connector of the present invention, and is a model diagram showing deflection and bending stress with respect to a load in a C-type spring.
FIG. 8 is an overall schematic view showing a conventional multi-fiber single-core conversion optical fiber with an optical fiber connector.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Multi-fiber single fiber conversion optical fiber with an optical fiber connector, 11 ... Single-core optical fiber (single-core optical fiber core wire), 12 ... Butt end (bare fiber), 13 ... Multi-fiber optical fiber (light Fiber ribbon fiber), 14 ... Optical fiber (bare fiber), 15 ... Optical fiber connector, 16 ... Base, 17 ... Base upper surface, 18 ... Holding lid, 19 ... Clamp means (C-type spring), 21 ... Aligning Mechanism (positioning groove), 23 ... optical fiber core wire (lead core portion), 25 optical fiber core wire (single core portion), 50 assembly fixing portion, 51 elastic body protector.

Claims (2)

A multi-core single-core conversion optical fiber (10) with an optical fiber connector for branching the multi-core optical fiber (13) into a plurality of single-core optical fibers (11),
A plurality of single-core optical fibers provided with a lead-out core portion (23) by removing the coating on one end portion, and a plurality of lights constituting the lead-out core portion of these single-core optical fibers constituting a multi-core optical fiber An assembly fixing portion (50) that is assembled and fixed in parallel at a pitch corresponding to the arrangement of the fibers (14), and a butt end portion (12) of each single-core optical fiber protruding from the assembly fixing portion are fixed, and the butt An optical fiber connector (15) that butt-connects the end portion and the optical fiber of the multi-core optical fiber;
The optical fiber connector clamps between a base (16) and a multi-core optical fiber that is mounted on the base upper surface (17) and butt-connected to a single-core optical fiber between the base and a butt state. The holding lid (18) for holding, the clamping means (19) for applying and releasing the clamping force to the base and the pressing lid, the butted end of the single-core optical fiber and the multi-fiber optical fiber between the base and the pressing lid And an aligning mechanism (21) that aligns and aligns so that they can be connected to each other.
One end of the assembly fixing portion is stored in an assembly fixing portion storage groove (50a) formed at one end in the longitudinal direction of the upper surface of the base, and the other end of the assembly fixing portion and the single-core optical fiber (11) The lead core part (23) is exposed between the covering part (11a),
The assembly fixing portion and the single-core optical fiber in the vicinity of the assembly fixing portion are covered with the elastic body protector (51) so as to maintain the bending radius of the lead-out core portion of the single-core optical fiber, and the elastic body. One end in the axial direction of the protector is fixed to the outer peripheral surface of the longitudinal end of the base and the holding lid of the optical fiber connector, and the other end of the elastic protector is covered with a plurality of single-core optical fibers ( 11a) are arranged in parallel and converged , and a space is secured between the lead- out core part and the inner surface of the elastic body protector. fiber.   The multi-fiber single-fiber conversion optical fiber with an optical fiber connector according to claim 1, wherein the multi-fiber optical fiber side optical fiber core wire (25) and the single-core optical fiber side lead fiber core portion (23) Have the same diameter dimension of 250 μm or more, a multi-fiber single-fiber conversion optical fiber with an optical fiber connector.

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