JP2003195132A - Coated optical fiber ribbon - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a coated optical fiber ribbon which can easily be separated halfway with high reliability from the coated optical fiber ribbon in which a plurality of optical fibers united with resin are arranged in parallel. <P>SOLUTION: The optical fibers 1 are divided into one center-part group which is arranged at the center part of the ribbon and two edge-part groups which are arranged at both edge parts of the ribbon, and the groups are arranged at fixed distances; and the optical fibers are arranged in the groups all in parallel to constitute the coated optical fiber ribbon 3 which are entirely covered with resin 2 in a ribbon form, so that halfway single-core fiber separation by a single-core fiber separating tool can easily be performed with high reliability. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an optical fiber ribbon, and more particularly, to a structure of an optical fiber ribbon capable of safely and easily intermediately separating a single optical fiber strand. Here, the term "intermediate separation" refers to separation at a position other than both ends of the optical fiber ribbon.

[0002]

2. Description of the Related Art A plurality of optical fiber strands are arranged in parallel, and all of them are covered with resin in a tape form. There has never been an optical fiber ribbon which has a structure that can be safely and easily separated into individual fiber strands. Conventionally, an optical fiber ribbon that can be separated in the middle from one optical fiber ribbon is divided into a group of optical fiber strands.First, a group of optical fiber strands is grouped. To form a unit tape core wire, and connect a plurality of these arranged in parallel with each other with resin to form a connected tape core wire having a number of strands that is a multiple of the number of strands of the unit tape core wire. And, if necessary,
It could be separated into unit tape cores.

An example of such a conventional optical fiber ribbon is shown in FIG. In the figure, reference numeral 1 denotes an optical fiber elemental wire in which a glass fiber is coated with a resin, and several unit cores of the elemental fiber 1 are coated in a tape shape with a resin 2 for tape to form a unit tape core wire 3. The figure illustrates a case where the number of optical fibers of the group is four. Next, a plurality of the unit tape core wires 3 are arranged in parallel and connected by the common coating 4 to form a connecting tape core wire 5. The figure illustrates the case where the number of unit tape cores is two. When the connecting tape core wire 5 is divided, the common coating 4 is removed and the unit tape core wire 3 is divided, contrary to the construction procedure. Furthermore, unit tape core wire 3
To separate each fiber into a single optical fiber strand,
It has never been done before.

However, recently, in connection with the development of transmission equipment, the demand for intermediate separation of the optical fiber ribbon into a single core has been increasing. If the conventional optical fiber tape core wire is to be separated into a single core, it is necessary to use a shearing stress type single core separation tool or the like to try to force the separation. There is a possibility that the coating may be broken and the glass fiber may be damaged, and there is a concern that the strength of the optical fiber may be reduced. The single-core separation tool is a tool that makes it easy to peel off the resin for tape at the end of the optical fiber ribbon to facilitate splitting into optical fiber strands.
It is a stapler type that can be held by one hand and can apply a pressing force to a part of the optical fiber ribbon through a pair of shearing blades.

By using this shear stress type single-core separation tool,
As an example, a case in which a 4-fiber optical fiber ribbon is separated into intermediate single fibers will be described with reference to FIG. FIG. 5 is a cross-sectional view of an intermediate portion of the optical fiber tape core wire. In the figure, 1 is an optical fiber element wire, 2 is a resin for tape, 3 is an optical fiber tape core wire, and 11 and 12 are single-core separation tools. A pair of shear blades are shown. First, as shown in (A), a pair of shear blades 11 and 12 sandwich a position where the optical fiber ribbon is to be separated into a single core from above and below. Next, as in (B), the tool is pressed with a finger in a direction in which the shearing blades 11 and 12 are engaged with each other, and a pressing force is applied to the optical fiber tape core wire to cause cracks in the tape resin 2. In the case of the figure, a crack is formed between the two cores in the central portion and one core at each end. Although (C) shows the optical fiber tape core wire removed from the single-core separation tool after that, although the resin 6 for tape has cracks 6, the coating resin forming the optical fiber element wire 1 is also damaged. ing.

The crack 6 generated in the tape resin 2 can be used to separate the tape resin 2 from the tape resin 2 to separate the optical fiber wires 1 into single cores. If the coating resin that constitutes it is also damaged, there is a possibility that the inner glass fiber portion will also be damaged and the strength will be deteriorated, and it can be said that a great problem remains in the reliability of this portion. That is, it can be said that the use of the single-core separation tool for such an intermediate separation purpose is inappropriate. Not only the shear stress type, but the only use of single-core separation tools is appropriate,
It is said that the end of the optical fiber ribbon is used as a trigger for the separation of the single fiber, and that portion is removed in a later work process.

[0007]

DISCLOSURE OF THE INVENTION The present invention provides a structure of an optical fiber ribbon which can easily separate a single optical fiber strand from an optical fiber ribbon without deteriorating reliability. It is a thing.

[0008]

SUMMARY OF THE INVENTION An optical fiber ribbon according to the present invention comprises a plurality of optical fiber strands arranged in a central group in which a plurality of optical fiber strands are arranged in the central portion of the tape and two optical fiber strands arranged in both edges of the tape. Separated from the edge group, with a fixed distance between the groups, adjacent optical fibers are all arranged in parallel within the group, and the whole of these are covered with resin in a tape shape. It is an optical fiber ribbon. Then, it is convenient in actual use that the number of optical fiber strands of the two edge groups arranged on both edges of the tape is the same at both ends, and the number of optical fiber strands is 3 to 8. The case is practical and effective.

By configuring the optical fiber ribbon as described above, a shear stress type single core separation tool or the like can be used safely and effectively. With the above configuration, a gap is always generated between the groups, the optical fiber element wire does not exist in this gap, and only the resin for tape fills this space. And there are always two gaps. The ends of the shearing blades of the single-core separating tool hang on these two gaps. The cause of the problem in the prior art is that the end of the shearing blade of the single-core separating tool is hooked where the optical fiber wires are in close contact with each other, which causes the coating resin of the optical fiber wires to be destroyed.

The present invention will be described with reference to FIG. In the figure, 1 is an optical fiber strand, 2 is a tape resin, 3 is the entire optical fiber ribbon, and 7 is a gap. This figure shows an example in which the number of optical fiber strands of the optical fiber ribbon according to the present invention is four, and the number of optical fiber strands is two in the central group and one in the end group. Is an example. Two gaps 7 are formed between the groups.

With reference to FIG. 2, the method for separating the intermediate single cores of the optical fiber ribbon according to the present invention will be described. FIG. 2A is the same as FIG.
The state in which the middle of the 4-core optical fiber tape shown in (4) is sandwiched by a shear stress type single-core separation tool is shown. As can be seen from comparison with FIG. 5 showing the case of the conventional optical fiber ribbon, the shear stress due to the shearing blade is mainly generated in the gap portion 7,
The crack 6 generated here extends over the central group and the end group, and the end of the crack 6 reaches the surface of the resin 2 for tape after contacting the surface of the optical fiber bare wire of each group. FIG. 2B shows the optical fiber tape core wire removed from the single-core separation tool after that, and the generated crack 6 is held as it is. A crack connecting the surface of the optical fiber element wire 1 and the surface of the tape resin 2 is an important crack that can be used for single-core separation. If the optical fiber strands 1 connected to this crack are separated, then the adjacent optical fiber strands 1 can be easily separated in sequence, and since this crack can be formed in all groups, all optical fibers in all groups can be separated. The wires can be separated in the middle. According to the optical fiber tape core wire of the present invention, since the shearing blades are inserted into the two gap portions, the optical fiber element wire is not crushed or damaged and is safe.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The optical fiber tape core wire of the present invention is divided into a group of central portions arranged at the central portion of the tape and a group of edge portions arranged at both edge portions of the tape. Since it creates a gap between groups, it can be applied to optical fiber ribbons of various numbers of strands, but in practice, the number of fiber cores in the edge groups on both edges of the tape is the same, It is more convenient for work to make the tape symmetrical, and it is effective to apply it to 3 to 8 cores because it is frequently used. In Fig. 3, the number of cores is 3,
The cross-sectional structure example in the case of left-right symmetry of the optical fiber ribbons of 4, 5, 6, 7, and 8 is shown. The reference numerals in these figures are the same as those in FIG. 1 and their explanations are omitted. Even if there are several concentric numbers, there are possible variations. All the illustrated optical fiber tape core wires have two gap portions 7 and have the above-mentioned single-fiber separation property.
The ends of the shearing blades should hang on these two gaps 7. Conversely, it is necessary to use a shear blade of such width.

[0013]

[Examples] A four-core optical fiber tape core wire was actually manufactured and the separability of the intermediate single fiber was evaluated. The structure of the prototype optical fiber tape core wire is the same as that shown in FIG. 1, the dimensions are 1.2 mm in width and 0.4 mm in thickness, and the width of the gap is 0.0
It was 6 mm. The diameter of the optical fiber is 0.25m.
m standard size. The material forming the tape is a urethane acrylate-based UV curable resin. When an intermediate single-fiber separation property was investigated with a shear stress type single-fiber separation tool on this optical fiber tape core wire, about 50 samples,
It was confirmed that the single-core separability was all good. In addition, the safety was confirmed without the damage of the coating of the fiber strand and the deterioration of the strength of the fiber due to this work.

[0014]

According to the optical fiber ribbon according to the present invention, it is possible to easily and safely separate the optical fiber strands in the middle of the optical fiber ribbon, so that the workability is improved and the optical fiber is improved. It is possible to build a highly reliable system that does not cause the strength deterioration of the.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an optical fiber ribbon according to the present invention.

FIG. 2 is a transverse cross-sectional view for explaining the single-fiber separation method of the optical fiber ribbon according to the present invention.

FIG. 3 is a cross-sectional view showing an example of a 3- to 8-fiber optical fiber ribbon according to the present invention.

FIG. 4 is a cross-sectional view of a conventional coupled optical fiber tape core wire.

FIG. 5 is an explanatory diagram showing a problem in the conventional single fiber separation of the optical fiber ribbon.

[Explanation of symbols]

1: Optical fiber strand 2: Resin for tape 3: Optical fiber ribbon 4: Common coating 5: Connecting tape 6: crack 11, 12: a pair of shear blades

Claims (3)

[Claims] 1. A plurality of optical fiber strands are divided into one central group arranged at the central part of the tape and two edge groups arranged at both edge parts of the tape, and a fixed distance between the groups. The optical fiber ribbons are arranged adjacent to each other in the group and all of them are arranged in parallel, and all of them are covered with resin in a tape shape. 2. The number of optical fiber strands of the two end groups is the same at both ends.
Alternatively, the optical fiber ribbon according to claim 2 3. The optical fiber ribbon according to claim 1, wherein the number of optical fiber strands is 3 to 8.