JP4448412B2 - End processing method for optical fiber cable - Google Patents

Description

  The present invention relates to an optical fiber cable terminal processing method, and more particularly, to an optical fiber cable terminal process performed to connect an optical fiber to a required length when connecting the optical fibers.

  The optical fiber cable includes, for example, a protective layer made of metal formed in a tubular shape with a communication hole provided therein, and an optical fiber loosely inserted into the communication hole and covered with a UV curable resin. Yes.

Since such an optical fiber cable is laid over a long distance, the optical fibers are appropriately connected using a closure, a joint box, a repeater, or the like.
Among these, for example, a metal tube (annular protective layer) exposed from the optical cable terminal is inserted into the closure, and the connection portion between the optical fibers taken out by disassembling the metal tube is stored together with the extra length. What has the pressure | voltage resistant and watertight structure connection part storage body which performs is known (for example, refer patent document 1).

  When connecting the optical fibers described above, a so-called lead-out operation is performed in which the end of the optical fiber cable is disassembled to expose the optical fiber from the cable end over a required length (note that the above-described preceding operation is performed). In the technical literature, the dismantling process of the optical fiber terminal is expressed by the term “drawer.” It is impossible to pull out the optical fiber from the cable because the terminal process cannot be performed at the cable end on the opposite side).

JP2000-193860 (2nd page, FIG. 5)

By the way, in the above-described optical fiber lead-out operation, the protective tube is simply cut out by using a tool.
Since the metal tube is harder than the UV resin covering the optical fiber, the optical fiber may be damaged if the optical fiber contacts the cut end. Further, the cut off end portion may have an edge, and when the optical fiber comes into contact, it is more easily damaged.

  Therefore, when the exposed optical fiber comes into contact with the edge during the optical fiber connection operation, the optical fiber that is weak against external force is immediately damaged, and it is necessary to perform the extraction operation again. For this reason, the connection work of the optical fiber required skill.

  Accordingly, an object of the present invention is to provide an optical fiber cable terminal processing method capable of safely and easily extracting an optical fiber without damaging the optical fiber loosely inserted in the optical fiber cable. .

In order to solve the above problems, the optical fiber cable terminal processing method according to the present invention employs the following technical means.
That is, the terminal processing method of an optical fiber cable according to claim 1 is a method of forming a protective layer made of a metal having a communication hole provided therein and formed into a tubular shape, and light coated loosely into the communication hole and covered with a UV curable resin. An optical fiber cable end treatment method comprising a fiber, and a cylindrical body formed of a member having a Young's modulus lower than that of the UV curable resin and formed to be able to be inserted into the communication hole. A cylindrical body insertion step in which a required depth is inserted from the end of the optical fiber cable so that the fiber is inserted into the cylindrical body, and a tip portion of the cylindrical body inserted in the cylindrical body insertion step is left in the communication hole. , the protective layer is removed over the desired position on the terminal of the optical fiber cable, anda cylindrical body exposure step of exposing while protected by the cylindrical body of said optical fiber, said optical fiber cable The cylinder includes a first coating layer coated on an upper layer of the protective layer and a second coating layer coated on an upper layer of the first coating layer, and a jelly filled in the communication hole. The body exposing step removes the first and second covering layers together with the protective layer, and the optical fiber cable is formed by dividing the protective layer into n in the circumferential direction, and before the cylindrical body inserting step, After the second coating layer is removed to expose the first coating layer, the first coating layer is applied over a required length so as to leave the first coating layer on the terminal side at a required position. A cylindrical layer removing step, wherein the cylindrical body insertion step requires the cylindrical body to be removed from the end of the optical fiber cable while overflowing the jelly from a portion removed annularly in the coating layer removing step. It is characterized by depth insertion .
Terminal processing method for an optical fiber cable according to claim 2, in claim 1 Oite has a wire attachment step of securing the wire to the optical fibers of the terminal of the optical fiber cable in front of the cylindrical body insertion step The cylindrical body inserting step inserts the cylindrical body from the end of the optical fiber cable in a state where the optical fiber is stretched by pulling the wire rod while inserting the wire rod through the cylindrical body. It is characterized by that.
According to a third aspect of the present invention, there is provided an optical fiber cable terminal processing method according to the second aspect , wherein after the tubular body exposing step, the fixing portion between the wire and the optical fiber is removed to remove the wire and the tubular body. It has a lead-out step for extracting and exposing the optical fiber over a required length.

  According to the present invention, a cylindrical body made of a member having a Young's modulus lower than that of the UV curable resin covering the optical fiber is inserted into the communication hole into which the optical fiber is loosely inserted, thereby protecting the optical fiber. However, since the tube is disassembled, the cylinder can absorb and buffer the external force during the disassembly operation, and the optical fiber can be safely delivered without damaging the optical fiber.

  Moreover, in the terminal processing method of the optical fiber cable filled with jelly, when the cylindrical body is inserted into the communication hole after removing the covering layer over a required length (for example, 5 cm to 10 cm) at a required position, The jelly filled in the hole is extruded from the end of the protective layer by the volume of the cylinder inserted, and the protective layer split surface exposed in the place where the covering layer is removed (in the circumferential direction) Since the overflow of the n-divided dividing surface) makes the insertion of the cylinder extremely smooth, it is possible to carry out a safe mouth-out operation while efficiently discharging the jelly filled in the communication hole in the protective layer. it can.

  Also, by sticking the wire rod to the end of the optical fiber in advance, and inserting the cylinder while stretching the optical fiber through the wire rod, the optical fiber does not contact the communication hole of the protective layer, and smoothly A cylinder can be inserted.

  Next, an embodiment of an optical fiber cable terminal processing method according to the present invention will be described with reference to the accompanying drawings. In the figure, symbol A indicates an optical fiber cable.

First, before describing the embodiment of the terminal processing method of the optical fiber cable A, the configuration of the optical fiber cable A will be described.
The optical fiber cable A is illustrated as being suitable for being laid on the seabed. As shown in FIG. 1, the optical fiber cable A is formed in a tubular shape with a communication hole 1a provided therein, and 3 A protective layer 1 made of equally divided metal, an optical fiber 2 having a known structure in which a core and a clad that are loosely inserted in the communication hole 1a and through which light passes are coated with a UV curable resin, and light that is filled in the communication hole 1a. A jelly 3 that protects the fiber 2 from water running (water immersion) and the like, and a tensile body 4 (twisted spirally in the longitudinal direction of the cable and provided in a plurality around the outer periphery of the protective layer 1 in the circumferential direction. Steel wire), a thin-cylindrical copper coating 5 coated with the strength member 4, and a coating layer 6 (insulator) made of a resin coated with the copper coating 5.

  In this embodiment, the optical fiber cable A in which the protective layer 1 is divided into three equal parts in the circumferential direction is illustrated. However, n divisions (n The terminal processing method of the present embodiment can be applied to any number of optical fiber cables A.

  Next, the terminal processing method of the optical fiber cable A configured as described above will be described in detail with reference to FIGS.

  First, when connecting the optical fiber cable A to a repeater or the like, from the required position of the optical fiber cable A to the terminal so that the optical fiber 2 is led out to a predetermined length including the required extra length. The covering layer 6 is cut over to expose the copper coating 5 (see FIG. 2).

  Next, the copper sheath 5 is cut in an annular shape over a required length (for example, 5 cm to 10 cm) from a position shifted from the cut position of the coating layer 6 toward the end of the optical fiber cable A, thereby exposing the strength member 4a. At the same time, the copper sheath 5 at the end of the optical fiber cable A is cut away to expose the strength member 4b (covering layer removing step: see FIG. 3).

Next, the strength member 4b exposed on the outer periphery of the cut end portion of the optical fiber cable A is gradually expanded from the cut portion of the copper sheath 5 at the end portion of the optical fiber cable A toward the end of the optical fiber cable A. Bend out (see Fig. 4).
And the edge part of the wire 7 is adhere | attached on the terminal of the optical fiber 2 exposed from the terminal of the optical fiber cable A with an adhesive (refer to FIG. 5).

When the wire rod attaching process is completed, a cylindrical body 8 having a required diameter that can be inserted into the communication hole 1a and made of a soft member having a Young's modulus lower than that of the UV curable resin that is the coating material of the optical fiber 2 is formed on the wire rod 7. For example, after passing through a PE tube, a Teflon tube (Teflon: registered trademark), etc., the optical fiber 2 is stretched so that the optical fiber 2 is kept straight by pulling the wire 7, and the plurality of optical fibers 2 are tubed. The required depth cylinder 8 is inserted from the end of the optical fiber cable A so as to be inserted into the body.
At this time, the jelly 3 filled in the communication hole 1a overflows from the end 1b of the protective layer to the outer surface by the volume of the cylinder 8 inserted. Furthermore, since the copper sheath 5 is excised, from the exposed portion of the tensile body 4a, through the respective divided surfaces 1b of the protective layer 1 divided into three equal parts and the gap between the adjacent tensile bodies 4a, Since it overflows to the outer surface of the protective layer 1, it becomes possible to insert the cylinder 8 more smoothly (refer to FIG. 6, 7 for cylinder insertion process).

When the cylindrical body insertion process is completed, the copper sheath 5 that covers the end of the optical fiber cable A is removed from the portion where the copper sheath 5 is annularly cut, and the exposed strength member 4 is gradually expanded in diameter. (See FIG. 8).
Next, the tensile body 4 and the protective layer 1 are cut so as to be substantially aligned with the cutting position of the copper sheath 5, and the optical fiber 2 is exposed while being protected by the cylindrical body 8. The tip of the cylinder 8 remains in the communication hole 1a (cylinder exposure process: see FIG. 9).

And the cylinder 8 is extracted after a cylinder exposure process (refer FIG. 10).
Next, since the adhesive portion of the wire 7 and the optical fiber 2 is coated with an adhesive, there is a possibility that an excessive stress is applied. The extraction operation of the end processing of the fiber cable A is completed (extraction process: see FIG. 11).

  Thus, according to the terminal processing method of the optical fiber cable A according to the present embodiment, when the optical fiber cable A is disassembled, the fiber 8 is protected while the optical fiber 2 is protected by the cylindrical body 8, so that the optical fiber The optical fiber 2 can be safely taken out without damaging 2.

  In other words, conventionally, the work of disassembling the optical cable without damaging the optical fiber 2 requires skill, but if the terminal processing method for the optical fiber cable A according to the present embodiment is used. Since the risk of damaging the optical fiber 2 is eliminated, work skills are reduced.

  The terminal processing method for the optical fiber cable A according to this embodiment has been described above. However, the above-described embodiment shows an example of a preferred embodiment of the present invention, and the present invention is limited to this. It is not a thing.

  For example, the configuration of the optical fiber cable described above is a preferable example among those laid on the seabed, and the configuration of the cable is such that the optical fiber 2 is loosely inserted in the protective layer. If there is no particular limitation.

It is an expanded longitudinal cross-sectional view of the optical fiber cable used for the terminal processing method of the optical fiber cable concerning this Embodiment. It is process drawing of the terminal processing method of the optical fiber cable concerning this Embodiment, and shows the side surface of an optical fiber cable. It is process drawing of the terminal processing method of the optical fiber cable following FIG. It is process drawing of the terminal processing method of the optical fiber cable following FIG. It is process drawing of the terminal processing method of the optical fiber cable following FIG. FIG. 6 is a process diagram of an optical fiber cable terminal processing method following FIG. 5. FIG. 7 is a process diagram of the optical fiber cable terminal processing method following FIG. 6. FIG. 8 is a process diagram of the optical fiber cable end processing method following FIG. 7. FIG. 9 is a process diagram of the optical fiber cable terminal processing method following FIG. 8. FIG. 10 is a process diagram of the optical fiber cable terminal processing method following FIG. 9; It is process drawing of the terminal processing method of the optical fiber cable following FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS A Optical fiber cable 1 Protective layer 1a Communication hole 1b Dividing surface 2 Optical fiber 3 Jerry 4 (4a, 4b) Strength member 5 Copper coating 6 Coating layer 7 Wire material 8 Cylindrical body

Claims (3)

An optical fiber cable end processing method comprising: a protective layer made of a metal having a communication hole provided therein and formed into a tubular shape; and an optical fiber loosely inserted into the communication hole and covered with a UV curable resin. Because
A cylindrical body formed of a member having a Young's modulus lower than that of the UV curable resin and formed so as to be able to be inserted into the communication hole is required to be inserted from the end of the optical fiber cable so that the optical fiber is inserted into the cylindrical body. A cylinder insertion process to be inserted;
The protective layer is removed from the required position over the end of the optical fiber cable so that the tip of the cylindrical body inserted in the cylindrical body insertion step remains in the communication hole, and the optical fiber is A cylinder exposure process that exposes while protecting;
Have,
The optical fiber cable includes a first coating layer coated on an upper layer of the protective layer and a second coating layer coated on an upper layer of the first coating layer, and a jelly filled in the communication hole. Configured
The cylindrical body exposing step removes the first and second coating layers together with the protective layer,
The optical fiber cable has the protective layer divided into n in the circumferential direction,
After the second covering layer is removed and the first covering layer is exposed before the cylindrical body inserting step, the first covering layer is left at a required position so that the first covering layer is left on the terminal side. A coating layer removing step for removing the first coating layer in a ring shape over the
In the optical fiber cable, the cylindrical body insertion step inserts the cylindrical body from a terminal of the optical fiber cable while overflowing the jelly from a portion removed in an annular shape in the covering layer removal step. Terminal processing method. A wire attachment step of fixing a wire to the optical fiber of the end of the optical fiber cable before the cylindrical body insertion step;
In the cylindrical body insertion step, the wire body is inserted into the cylindrical body, and the cylindrical body is inserted from the end of the optical fiber cable in a state where the optical fiber is stretched by pulling the wire material. The terminal processing method of the optical fiber cable of Claim 1 characterized by these. After the cylindrical body exposing step, the wire rod and the optical fiber are cut off to remove the wire rod, and the cylindrical body is removed to expose the optical fiber over a required length. The terminal processing method of the optical fiber cable according to claim 2, wherein

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