JPH08327863A - Coated optical fiber - Google Patents

Abstract

PURPOSE: To make extra-length processing of coated fibers compact by adopting a structure obtd. by intermittently fixing coated optical fibers with peelable adhesive tape adhering parallel optical fibers at intervals in the longitudinal direction to a coated optical fiber. CONSTITUTION: The coated optical fiber 11 is constituted by paralleling the four optical fibers 12 formed by applying a required coating 12b of a UV resin, etc., on the outer periphery of the optical fibers 12a and fixing the respective optical fibers 12 with the peelable adhesive tapes 13 adhering these fibers from both ends at intervals in the longitudinal direction. Namely, the coated optical fiber is composed of the structure obtd. by alternately providing the coated optical fiber with the coupling parts A where the four optical fibers 12, 12,... are integrally coupled like a tape and the non-coupling parts B where the four optical fibers 12, 12,... are not coupled and held in a free state. Thereby, the handling is made easy and a high-density packaging of the optical fibers 12a to a cable by lamination is made possible. The individual taking out of the optical fibers 12 in the non-coupling parts B is possible and the taking-out and dropping-down of only the required optical fibers 12 are possible as well.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber core wire in which a plurality of optical fiber element wires arranged in parallel are fixed at intervals in the length direction.

[0002]

2. Description of the Related Art In recent years, in overhead optical cables, in order to increase the mounting density of optical fibers, a plurality of optical fiber wires 1 are arranged in parallel as shown in FIG. The one molded into (hereinafter, referred to as a tape core wire) is often used.

However, in such a tape core wire, since a plurality of optical fiber strands 1 are integrated over the entire length, the tape core wire must be withdrawn to the subscriber system. However, the demand at one withdrawal point is 1 ~
In the case of two cores, the remaining optical fiber remains unused and there is a problem that usage efficiency decreases. In addition, at that time, in order to connect with the single core wire from the subscriber side, a core wire converting device for converting the tape core wire into the single core wire must be used, and the transmission loss due to the connection is large, There were also problems such as difficulty in downsizing.

In order to solve this problem, the optical fiber strands 1, 1, ... Are intermittently integrated in the lengthwise direction as shown in FIG. There has been proposed a structure configured to have both the advantages of a core wire. That is, the core wire is a joint portion A in which the optical fiber element wires 1, 1, ...
1 has a structure in which the non-bonded portions B in the free state are alternately provided. According to this type of core wire, only the necessary wires can be dropped and the rest can be passed through, so that it is possible to flexibly respond to concentrated demand / sparse demand, and a single core wire conversion device is not required. Since it can be connected to the core wire, it has the advantages that transmission loss at the connection part can be reduced, the closure can be made compact, and switching and disconnection between core wires can be performed easily. . In addition,
FIG. 7 shows a cross section of the joint portion A.

[0005]

However, in such an optical fiber core wire, as is apparent from FIGS. 6 and 7, since there is a thickness difference d between the coupling portion A and the non-coupling portion B, the closure is closed. When the extra length processing of the core wire is performed inside, etc.
As shown in FIG. 8, bending stress is concentrated on the boundary portion between the joint portion A and the non-joint portion B, and the portion may be broken into a dogleg shape, which makes it impossible to carry out a compact core extra length treatment. was there. In FIG. 8, 3 is a closure and 4 is a cable body.

The present invention has been made in consideration of such a point, and a connecting portion in which optical fiber element wires are connected to each other,
It has the characteristics of the conventional core wire in which the non-coupling parts in which the optical fiber wires are in a free state are alternately provided, and
It is an object of the present invention to provide an optical fiber core wire capable of compacting the extra length processing of the core wire in a closure or the like.

[0007]

According to the present invention, a plurality of optical fiber strands are arranged in parallel, and these optical fiber strands are adhered from at least one side thereof at intervals in the length direction. It is characterized by being intermittently fixed by a peelable adhesive tape.

[0008]

In the optical fiber core wire of the present invention, the parallel optical fiber element wires are intermittently fixed by the peelable adhesive tape adhered from at least one side thereof at intervals in the longitudinal direction, By peeling off the peelable adhesive tape, all the required portions of the optical fiber strands can be returned to the free state, if necessary. Therefore,
Usually, it can be treated as a core wire in which a connecting portion and a non-bonding portion are alternately provided. On the other hand, when performing extra length treatment of the core wire in a closure or the like, by peeling the adhesive tape, Since it becomes possible to handle all the optical fiber strands of the portion as a single core wire in which the bending stress is not concentrated, it is possible to form the core extra length processing portion in a compact manner.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a perspective view showing an optical fiber core wire according to an embodiment of the present invention, and FIG. 2 is a view showing a sectional structure of a coupling portion A shown in FIG.

In FIGS. 1 and 2, the optical fiber core wire 11 includes an optical fiber element wire 12 having a required coating 12b made of UV resin or the like on the outer circumference of an optical fiber 12a.
The optical fiber wires 12 are arranged in parallel and are fixed to each other at intervals in the length direction by peelable adhesive tapes 13 adhered from both sides thereof. That is, the coupling portion A in which the four optical fiber strands 12, 12 ... Are integrally coupled in a tape shape, and the uncoupled portion in which the four optical fiber strands 12, 12, ... B
It has a structure in which is alternately provided.

The optical fiber core wire 11 thus constructed
In the above, the effect of providing the coupling portion A and the non-coupling portion B, that is, the handling is easy, the high density mounting of the optical fiber on the cable by stacking is possible, and the optical fiber at the non-coupling portion B Since the strands 12 can be individually taken out, only the required optical fiber strands 12 can be pulled out and withdrawn when the line is withdrawn to the subscriber system, and therefore flexible to both concentrated demand and sparse demand. It is possible to correspond to the
The effect that the transmission loss in the connection portion can be reduced can be obtained. In addition, by peeling off the adhesive tape 13 as necessary, the optical fiber element wire can be returned to the free state, that is, the single-core wire over the required length.

Therefore, as shown in FIG. 3, when the extra length treatment of the core wire is performed in the closure 14 or the like, the adhesive tape 1 is used.
By peeling off 3, the bending stress as in the conventional case is not locally concentrated, so that a more compact extra length treatment can be performed with a small curvature. In FIG. 3, reference numeral 15 denotes a cable body using the optical fiber core wire 11. Further, since any portion can be returned to the single core wire in this manner, it is not necessary to limit the core wire withdrawal to the non-coupling portion B, and the degree of freedom of withdrawal can be further increased.

Next, an example of an optical fiber cable using the optical fiber core 11 will be described. As shown in FIG.
This optical fiber cable has a spacer 1 in which a plurality of grooves 16 for accommodating optical fiber cores are formed in SZ twist on the outer circumference.
7, each of the plurality of optical fiber core wires 11 is provided in each groove 16 and at least the non-coupling portion B of each optical fiber core wire 11 is provided in each groove 16
The SZ inversion section 16a is stacked and housed so as to be located. Further, although not shown in the drawings, a presser coil and a sheath are sequentially provided on the outer side thereof.

In such an optical fiber cable, each optical fiber strand 12 is formed at the SZ inversion portion 16a of the groove 16.
Since it is in a free state, a large strain stress is applied to the optical fiber element wire 12 as in the case of accommodating a conventional tape core wire whose entire circumference is collectively covered on the optical fiber element wire. It is possible to prevent the deterioration of the transmission characteristics of the optical fiber due to the strain stress.

It should be noted that the present invention is not limited to the optical fiber core wire having a four-core structure as described in the above embodiment, but may be any number of core wires such as two cores, eight cores, and 16 cores. can do. Further, the adhesive tape 13 does not necessarily have to be adhered to both sides of the optical fiber strands 12 arranged in parallel, and may be adhered to only one side as long as the necessary adhesive strength can be obtained. Can be obtained.

[0017]

As described above, the optical fiber core wire of the present invention is intermittently separated by a peelable adhesive tape in which optical fiber element wires arranged in parallel are adhered from at least one side thereof at intervals in the longitudinal direction. As it has a fixed structure,
It is possible to combine the advantages of the tape core wire and the single core wire, and further, it is possible to make the extra length processing of the core wire in the closure compact.

[Brief description of drawings]

FIG. 1 is a perspective view showing an optical fiber core wire according to an embodiment of the present invention.

FIG. 2 is a diagram showing a cross-sectional structure of a joint portion A shown in FIG.

FIG. 3 is a diagram schematically showing a state of a core extra length processing in a closure of an optical fiber core according to an embodiment of the present invention.

FIG. 4 is a side view showing a state in which an optical fiber core wire according to an embodiment of the present invention is housed in a cable groove.

FIG. 5 is a perspective view showing an example of a conventional optical fiber core wire.

FIG. 6 is a perspective view showing another example of a conventional optical fiber core wire.

7 is a diagram showing a cross-sectional structure of a coupling portion A of the optical fiber core wire shown in FIG.

FIG. 8 is a diagram schematically showing a state in which a conventional optical fiber core wire is subjected to a core wire extra length processing in a closure.

[Explanation of symbols]

 11 ... Optical fiber core wire 12 ... Optical fiber element wire 12a ... Optical fiber 12b ... Coating 13 ... Releasable adhesive tape A ... Coupling portion B ... Non-coupling portion

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuyoshi Echigoya 2-1-1 Oda Sakae, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Showa Electric Wire & Cable Co., Ltd. 2-1-1, Oda-ku, Showa Electric Cable Co., Ltd. (72) Inventor Shogo Ohashi 2-1-1, Odae, Kawasaki-ku, Kanagawa

Claims (1)

[Claims] 1. A plurality of optical fiber strands are arranged in parallel, and these optical fiber strands are intermittently separated by a peelable adhesive tape which is adhered from at least one side thereof at intervals in the length direction. An optical fiber core, which is fixed to the.