JPH05224031A - Communication line and laying method therefor - Google Patents
Communication line and laying method thereforInfo
- Publication number
- JPH05224031A JPH05224031A JP5723992A JP5723992A JPH05224031A JP H05224031 A JPH05224031 A JP H05224031A JP 5723992 A JP5723992 A JP 5723992A JP 5723992 A JP5723992 A JP 5723992A JP H05224031 A JPH05224031 A JP H05224031A
- Authority
- JP
- Japan
- Prior art keywords
- communication line
- tubular member
- rear end
- communication
- laying
- 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
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/46—Processes or apparatus adapted for installing or repairing optical fibres or optical cables
- G02B6/50—Underground or underwater installation; Installation through tubing, conduits or ducts
- G02B6/52—Underground or underwater installation; Installation through tubing, conduits or ducts using fluid, e.g. air
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Electric Cable Installation (AREA)
- Light Guides In General And Applications Therefor (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は、管路に収納しておいた
通信線を、別の管路に圧力気体の流れにより転送して布
設する通信線の構造とその布設方法に関するものであ
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a communication line for transferring a communication line stored in a conduit to another conduit by a flow of a pressure gas and laying the same, and a method of laying the communication line. ..
【0002】[0002]
【従来の技術】従来、通信線の布設・回収の技術とし
て、特開平2−72723号公報に記載された方法があ
る。この方法を図4で説明する。図中、11はケーブ
ル、12,13は管状部材、14,15は接合部、16
はコンプレッサ、17は通信線、18は光ファイバ素
線、19は外被である。2. Description of the Related Art Conventionally, as a technique for laying and collecting communication lines, there is a method described in JP-A-2-72723. This method will be described with reference to FIG. In the figure, 11 is a cable, 12 and 13 are tubular members, 14 and 15 are joints, 16
Is a compressor, 17 is a communication line, 18 is an optical fiber element wire, and 19 is a jacket.
【0003】(A)図は、既設の管路に通信線を布設す
る方法の説明図である。ケーブル11は、複数本の管状
部材12が束ねられたものである。この管状部材12に
は、通信線が収納されていない状態でケーブルとしてあ
らかじめ布設されており、この管状部材12に通信線1
7が布設される。通信線17は、この例では、(C)図
に示すように、7心の光ファイバ素線18が集合され、
発泡ポリエチレンなどの軽量な外被19で被覆されたも
のである。管状部材13には、管状部材12に布設され
るべき通信線があらかじめ収納されており、搬入を容易
にするために、コイル状に巻かれている。この管状部材
13を、通信線を布設すべき現場に搬入して、その片端
に布設現場にあらかじめ布設しておいた既設の管状部材
12に接合部14において接合し、他端の接合部15に
おいて、コンプレッサ16を接続し、圧力気体を流し、
通信線を未設の管状部材13から既設の管状部材12に
導入することにより、通信線の布設を行なう。FIG. 1A is an explanatory view of a method of laying a communication line in an existing pipeline. The cable 11 is a bundle of a plurality of tubular members 12. The tubular member 12 is previously laid as a cable in a state where the communication line is not housed therein, and the tubular member 12 is provided with the communication line 1
7 is laid. In the communication line 17, in this example, as shown in FIG.
It is covered with a lightweight jacket 19 such as foamed polyethylene. In the tubular member 13, a communication wire to be laid on the tubular member 12 is stored in advance, and is wound in a coil shape for easy loading. This tubular member 13 is carried into a site where a communication line is to be laid, and one end of the tubular member 13 is joined to an existing tubular member 12 that has been laid in advance at the laying site at a joining portion 14, and at the joining portion 15 at the other end. , Connect the compressor 16 and let pressure gas flow,
The communication line is laid by introducing the communication line from the tubular member 13 which is not provided to the tubular member 12 which is already provided.
【0004】(B)図は、既設の管状部材12に布設さ
れている通信線を回収する方法の説明図である。通信線
は、未設の管状部材13を管状部材12の一端に接合部
14において接合し、管状部材12の他端に接合部15
において、コンプレッサ16を接続する。管状部材13
は空である。コンプレッサ16から管状部材12に圧力
気体を導入することにより、管状部材12に収納された
通信線が管状部材13に移動されて収納され、通信線の
回収ができる。FIG. 1B is an explanatory view of a method of collecting the communication line laid on the existing tubular member 12. The communication line joins the tubular member 13 which is not provided to one end of the tubular member 12 at the joining portion 14, and joins the joining portion 15 to the other end of the tubular member 12.
At, the compressor 16 is connected. Tubular member 13
Is empty. By introducing the pressure gas from the compressor 16 to the tubular member 12, the communication line accommodated in the tubular member 12 is moved to and accommodated in the tubular member 13, and the communication line can be collected.
【0005】このような従来の通信線の布設・回収方法
によると、特に、送通の開始時期において送通速度が非
常に遅いという問題点があった。According to such a conventional method of laying and collecting communication lines, there is a problem that the transmission speed is very slow especially at the start of transmission.
【0006】[0006]
【発明が解決しようとする課題】本発明は、上述した問
題点を解決するためになされたもので、通信線が収納さ
れた第1の管状部材と、通信線が収納されていない第2
の管状部材とを接合部で接合し、前記第1の管状部材の
接合部の反対側から圧力流体を供給し、前記通信線を圧
力気体流にのせて前記第2の管状部材側に転送する通信
線の布設方法において、通信線と管路内壁との密着をは
がし、摩擦を低減できる布設方法およびそれに適した通
信線を提供することを目的とするものである。SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and includes a first tubular member accommodating a communication line and a second tubular member not accommodating the communication line.
Of the first tubular member, and a pressure fluid is supplied from the opposite side of the first tubular member to the second tubular member to carry the communication line on the pressure gas flow. It is an object of the present invention to provide a method of laying a communication line, by which the communication line and the inner wall of the conduit can be peeled off from each other and friction can be reduced, and a communication line suitable for the method.
【0007】[0007]
【課題を解決するための手段】本発明は、管状部材に収
納されて、該管状部材と接合した別の管状部材に圧力気
体流により送通される通信線であって、その移動する後
端に、前記管状部材の内径より小さく、かつ、前記通信
線の外径より大きい風受けを設けたことを特徴とするも
のであり、また、通信線が収納された第1の管状部材の
片端を別の第2の管状部材に接続し、前記第1の管状部
材の他端を圧力気体供給装置と接続して、圧力気体流に
より前記第1の管状部材から前記第2の管状部材へ転送
する通信線の布設方法であって、前記通信線の後端に、
前記各管状部材の内径より小さく、かつ、前記通信線の
外径より大きい風受けを取り付けて転送することを特徴
とするものである。SUMMARY OF THE INVENTION The present invention is a communication wire housed in a tubular member and communicated by pressure gas flow to another tubular member joined to the tubular member, the moving rear end of the wire being a communication line. Is provided with a wind receiver smaller than the inner diameter of the tubular member and larger than the outer diameter of the communication line, and one end of the first tubular member accommodating the communication line is Connecting to another second tubular member and connecting the other end of the first tubular member to a pressure gas supply device to transfer from the first tubular member to the second tubular member by pressure gas flow. A method of laying a communication line, comprising:
A wind receiver smaller than the inner diameter of each of the tubular members and larger than the outer diameter of the communication line is attached and transferred.
【0008】[0008]
【作用】発明者らは、従来の方法による送通速度の低下
の原因を検討した結果、その主因が以下の点にあると推
定した。As a result of examining the cause of the decrease in the transmission speed by the conventional method, the inventors presumed that the main cause thereof is as follows.
【0009】まず、送通の際の管路内の通信線の状態を
観察したところ、管路の曲線部で、内壁に通信線が密着
している状態が認められた。送通速度の低下の原因は、
この内壁への通信線の密着のため摩擦力が高まっている
ためと思われる。すなわち、管路内の状況をみると、管
路内での圧力気体の圧力勾配は、図2に示すように、圧
力気体の入口で大きく、既設管路の出口で小さくなって
おり、さらに、一般に用いられる窒素や空気などの気体
は、圧縮性気体であるため、圧力気体入口での流速は非
常に遅く、出口に近づくほど、圧力低下によって体積が
膨張するため、流速は早くなる。したがって、圧力流体
を用いて通信線を搬送すると、布設中に通信線の周囲の
流体速度が、先端へ行くほど早くなることを意味する。
このため、通信線の先端がより早く動かされようとする
ため、通信線が管路内壁に密着されると考えられる。First, when the state of the communication line in the pipeline during the transmission was observed, it was observed that the communication line was in close contact with the inner wall at the curved portion of the pipeline. The cause of the decrease in transmission speed is
It is thought that the frictional force is increasing due to the close contact of the communication line with this inner wall. That is, looking at the situation in the pipeline, the pressure gradient of the pressure gas in the pipeline is large at the inlet of the pressure gas and small at the exit of the existing pipeline, as shown in FIG. Gases such as nitrogen and air that are generally used are compressible gases, so the flow velocity at the pressure gas inlet is very slow, and the volume expands as the pressure decreases toward the outlet, so the flow velocity becomes faster. Therefore, when the communication line is conveyed by using the pressure fluid, it means that the fluid velocity around the communication line becomes faster toward the tip during the installation.
Therefore, it is considered that the tip of the communication line tends to be moved more quickly, so that the communication line is closely attached to the inner wall of the conduit.
【0010】本発明によれば、通信線の後端が他の部分
に比較して大きな推進力を生ずるように風受けを設けて
おり、この部分が圧力気体流を受け止めて他の部分より
早く進み、通信線後端付近に通信線のたるみが生じてこ
のたるみが伝搬していくことにより、通信線と管路内壁
との密着をはがし、摩擦を低減して送通速度を高めるこ
とができるのである。According to the present invention, a wind receiver is provided so that the rear end of the communication line produces a large propulsive force as compared with the other portion, and this portion receives the pressurized gas flow and is earlier than the other portions. As the slack of the communication line is generated near the rear end of the communication line and propagates due to this slack, the communication line and the inner wall of the pipeline are peeled off from each other, friction can be reduced, and the transmission speed can be increased. Of.
【0011】[0011]
【実施例】図1は、本発明の一実施例の説明図であり、
図4で説明した管状部材の一部の断面と考えてよい。図
中、1は管状部材、2は通信線、3は風受け部、4は圧
力気体流である。風受け部3は、通信線2の進行方向か
らみて後端部に着脱可能に取り付けられており、この実
施例では、ほぼ紡錘形状に構成されている。その外径
は、管路1の内径よりかなり小さく、かつ、通信線2の
外径より大きい。通信線2を圧力気体流4によって圧送
する際に、風受け部3に推進力が生じるから、後端部が
他の部分より早く進もうとする状態となり、通信線2の
後端部付近に通信線のたるみが生じてこのたるみが伝搬
していくことにより、通信線2と管状部材1の内壁との
密着をはがし、摩擦を低減して送通速度が高められる。
風受け部3の形状は、紡錘形状に限られるものではな
い。球形状や、後部を底面とした円錐形状など、適宜の
形状を採用できる。DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory view of an embodiment of the present invention.
It can be considered as a cross section of a part of the tubular member described in FIG. In the figure, 1 is a tubular member, 2 is a communication line, 3 is a wind receiver, and 4 is a pressurized gas flow. The wind receiving portion 3 is detachably attached to the rear end portion when viewed from the traveling direction of the communication line 2, and in this embodiment, it has a substantially spindle shape. The outer diameter thereof is considerably smaller than the inner diameter of the conduit 1 and larger than the outer diameter of the communication line 2. When the communication line 2 is pressure-fed by the pressure gas flow 4, a propulsive force is generated in the wind receiving part 3, so that the rear end portion tries to advance faster than other parts, and the vicinity of the rear end portion of the communication line 2 is reached. The slack of the communication line is generated and the slack is propagated, so that the communication line 2 and the inner wall of the tubular member 1 are separated from each other, friction is reduced, and the transmission speed is increased.
The shape of the wind receiving portion 3 is not limited to the spindle shape. Appropriate shapes such as a spherical shape and a conical shape with the rear part as the bottom surface can be adopted.
【0012】具体的な実験結果について説明する。評価
を行なった管路の構成は、長さ100m、内径6mm、
外径8mmのポリエチレン製管路を1m径の円形に束取
りし、これを2本接続して行なった。すなわち、図4
(A)の管状部材3が2本接続された状態である。その
うちの1本の管路には、250μm径の光ファイバ素線
7心を図4(C)に示すように配列し、発泡ポリエチレ
ンを被覆して外径2mmに仕上げた100mの長さの光
ファイバケーブルを通信線として挿入した。そして、通
信線が挿入された管路の接続端と反対側の端から圧力5
kg/cm2 の圧縮空気を送り込み、通信線の転送の実
験を行なった。Specific experimental results will be described. The configuration of the evaluated pipeline is 100 m in length, 6 mm in inner diameter,
A polyethylene pipe having an outer diameter of 8 mm was bundled into a circle having a diameter of 1 m, and two bundles were connected. That is, FIG.
The two tubular members 3 of (A) are in a connected state. In one of them, seven cores of optical fiber having a diameter of 250 μm are arranged as shown in FIG. 4 (C), and light having a length of 100 m, which is coated with foamed polyethylene and has an outer diameter of 2 mm, is formed. A fiber cable was inserted as a communication line. Then, pressure 5 is applied from the end on the side opposite to the connection end of the conduit in which the communication line is inserted.
A compressed air of kg / cm 2 was blown in, and an experiment of transferring a communication line was conducted.
【0013】まず、比較例として、通信線の後端部を単
に切断しただけのものを用いた。この場合は、最初の5
0mの送通に4分30秒を要し、後半の50mに3分2
0秒を要したため、100mの送通に計7分50秒が必
要であった。布設実験中を通して、通信線は束状に巻か
れた管路の内壁に付着して、ずるずるすべりながら移動
しており、全長に大きな摩擦が生じていることが窺え
た。First, as a comparative example, one in which the rear end of the communication line was simply cut was used. In this case, the first 5
It took 4 minutes and 30 seconds to send 0m, and 3 minutes and 2 minutes to 50m in the latter half.
Since it took 0 seconds, it took 7 minutes and 50 seconds to send 100 m. Throughout the laying experiment, it was confirmed that the communication line adhered to the inner wall of the pipe line wrapped in a bundle and was sliding and moving, causing a large amount of friction over the entire length.
【0014】次に、本発明の実施例として、この通信線
の後端に、直径4mm、長さ6mmの図1に示すような
紡錘形状の風受けを取り付けて、上記と同じく送通を行
なった結果、100m全長の送通が3分40秒で完了し
た。この布設中の通信線は、後端付近が尺取り虫のよう
に間欠的に寸動し、この際、通信線が管路内壁から浮き
上がるのが確認された。Next, as an embodiment of the present invention, a spindle-shaped wind receiver having a diameter of 4 mm and a length of 6 mm as shown in FIG. 1 is attached to the rear end of the communication line, and the same communication as above is performed. As a result, the 100 m full length transmission was completed in 3 minutes and 40 seconds. It was confirmed that the communication line during the laying intermittently moved around the rear end like a worm, and at this time, the communication line floated up from the inner wall of the conduit.
【0015】さらに、この風受けの大きさの最適な値を
求めた。管路の内径を変えて、2mm径の通信線につい
て100mの送通時間を測定して評価した。図3は、そ
の結果を示すが、図の斜線でハッチングした領域が、従
来技術で必要とされた送通時間の75%以下に送通時間
が短縮できる風受け部の直径の範囲を表している。この
結果から、風受け部の直径は、管路の内径の70%より
小さく、管路の内径と通信線の外径との差の30%を通
信線外径に加えた径より大きい範囲が有効であることが
わかる。この関係は、通信線の直径が1〜8mm、管路
の内径が3〜20mmの範囲で認められた。一方風受け
の長さについては、3〜20mmの範囲で特性の差異は
認められなかった。他の形状でも、風受け部の寸法の関
係は、上述した範囲で有効である。Further, the optimum value of the size of this wind receiver was obtained. The inner diameter of the conduit was changed, and a 100 m transmission time was measured and evaluated for a communication wire having a diameter of 2 mm. FIG. 3 shows the results, and the hatched area in the figure represents the range of the diameter of the wind receiving portion that can reduce the sending time to 75% or less of the sending time required in the conventional technique. There is. From this result, the diameter of the wind receiving part is smaller than 70% of the inner diameter of the conduit and larger than the diameter of the communication wire outer diameter obtained by adding 30% of the difference between the inner diameter of the conduit and the outer diameter of the communication wire. It turns out to be effective. This relationship was recognized when the diameter of the communication line was 1 to 8 mm and the inner diameter of the conduit was 3 to 20 mm. On the other hand, regarding the length of the wind receiver, no difference in characteristics was observed in the range of 3 to 20 mm. Even with other shapes, the dimensional relationship of the wind receiving portion is effective within the range described above.
【0016】風受け部の外径の上限が決まる理由につい
ては、適量の気体が風受け部と管路内壁との間隙を抜け
て、通信線に推進力を与えるためと考えられる。The reason why the upper limit of the outer diameter of the wind receiving portion is determined is considered to be that a proper amount of gas passes through the gap between the wind receiving portion and the inner wall of the conduit to give a propulsive force to the communication line.
【0017】また、本発明の方法では、曲がり部を有す
る管路においても、通信線と管路内壁との密着をはが
し、摩擦を低減できるため、特に、曲がりの多い布設ル
ートにおいて有効であり、通信線を収納して布設現場に
搬入する管状部材を束状の状態で使用する場合や、布設
すべき管状部材が曲がりを多く含んで布設されている場
合などにも有効である。このため、制約の大きい布設工
事場所、例えば、ビル内や構内の配線に用いると有効で
ある。Further, according to the method of the present invention, even in a pipeline having a curved portion, the contact between the communication line and the inner wall of the pipeline can be peeled off and friction can be reduced. Therefore, the method is particularly effective in a laying route with many bends. This is also effective when the tubular members that store the communication lines and are carried into the installation site are used in a bundled state, or when the tubular members to be installed are installed with many bends. For this reason, it is effective to use it for installation work places with large restrictions, for example, wiring in buildings and premises.
【0018】[0018]
【発明の効果】以上の説明から明らかなように、本発明
によれば、一方の管路に収納された通信線を、これに接
合された他方の管路へ転送する方法において、通信線と
管路内壁との密着をはがし、摩擦を低減できることよっ
て、より短時間で通信線を転送できるという効果があ
る。As is apparent from the above description, according to the present invention, in the method of transferring the communication line accommodated in one pipeline to the other pipeline joined thereto, the communication line Since the contact with the inner wall of the conduit can be removed and the friction can be reduced, the communication line can be transferred in a shorter time.
【図1】本発明の一実施例の説明図である。FIG. 1 is an explanatory diagram of an embodiment of the present invention.
【図2】管路内の圧力勾配を示す線図である。FIG. 2 is a diagram showing a pressure gradient in a pipeline.
【図3】風受け部の有効な直径を決める実験結果を示す
線図である。FIG. 3 is a diagram showing an experimental result for determining an effective diameter of a wind receiving part.
【図4】従来の通信線の布設・回収方法の説明図であ
る。FIG. 4 is an explanatory diagram of a conventional method of laying and collecting communication lines.
1 管状部材 2 通信線 3 風受け部 4 圧力気体流 1 Tubular member 2 Communication line 3 Wind receiver 4 Pressure gas flow
───────────────────────────────────────────────────── フロントページの続き (72)発明者 田中 茂 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 森光 武則 東京都千代田区内幸町一丁目1番6号 日 本電信電話株式会社内 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Shigeru Tanaka 1 Taya-cho, Sakae-ku, Yokohama-shi, Kanagawa Sumitomo Electric Industries, Ltd. Yokohama Works (72) Inventor Takenori Morimitsu 1-6, Uchisaiwai-cho, Chiyoda-ku, Tokyo No. Japan Telegraph and Telephone Corporation
Claims (2)
合した別の管状部材に圧力気体流により送通される通信
線であって、その移動する後端に、前記管状部材の内径
より小さく、かつ、前記通信線の外径より大きい風受け
を設けたことを特徴とする通信線。1. A communication line which is housed in a tubular member and is sent by pressure gas flow to another tubular member joined to the tubular member, wherein the moving rear end has an inner diameter larger than that of the tubular member. A communication line characterized in that it is provided with a wind receiver that is small and larger than the outer diameter of the communication line.
端を別の第2の管状部材に接続し、前記第1の管状部材
の他端を圧力気体供給装置と接続して、圧力気体流によ
り前記第1の管状部材から前記第2の管状部材へ転送す
る通信線の布設方法であって、前記通信線の後端に、前
記各管状部材の内径より小さく、かつ、前記通信線の外
径より大きい風受けを取り付けて転送することを特徴と
する通信線の布設方法。2. One end of a first tubular member accommodating a communication line is connected to another second tubular member, and the other end of the first tubular member is connected to a pressure gas supply device to obtain a pressure. A method of laying a communication wire for transferring from the first tubular member to the second tubular member by a gas flow, wherein the communication wire is provided at a rear end of the communication wire and is smaller than an inner diameter of each of the tubular members. A method of laying a communication line, characterized in that a wind receiver larger than the outer diameter of the cable is attached and transferred.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP5723992A JPH05224031A (en) | 1992-02-12 | 1992-02-12 | Communication line and laying method therefor |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP5723992A JPH05224031A (en) | 1992-02-12 | 1992-02-12 | Communication line and laying method therefor |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH05224031A true JPH05224031A (en) | 1993-09-03 |
Family
ID=13049986
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP5723992A Pending JPH05224031A (en) | 1992-02-12 | 1992-02-12 | Communication line and laying method therefor |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH05224031A (en) |
-
1992
- 1992-02-12 JP JP5723992A patent/JPH05224031A/en active Pending
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