JP2002189155A - Optical fiber cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical fiber cable having excellent side pressure resistance, bending resistance and twisting resistance while keeping desired strength and signal transmission performance. SOLUTION: A plurality of twisted optical fiber codes 2 are covered with an inner resin coating layer 3 and the inner resin coating layer 3 is covered with a high tensile fiber layer 4. The outside of the layer 4 is covered with an external resin coating layer 5. A high tensile fiber layer 6 is disposed in the center of the group of the optical fiber codes 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber cable mainly used for transmitting signals in moving equipment.

[0002]

2. Description of the Related Art FIG.
Is shown in cross section. This optical fiber cable 11
Has a structure in which a tension member 13 made of a steel stranded wire rope or the like is provided at the center of a plurality of twisted optical fiber cords 12 and these are covered with a resin coating layer 14 for corrosion protection such as polyurethane. I have.

[0003]

The optical fiber cable 11 having the above-described structure has excellent strength because of the provision of a high-rigidity tension member 13 at the center thereof. When the optical fiber cord 12 that is in direct contact with the tension member 13 undergoes physical deformation (plastic deformation) when receiving a large lateral pressure, bending, twisting, or the like, the signal transmission loss is reduced. In some cases, it was difficult to keep the accuracy high.

[0004] The present invention has been made in view of such a point, and is capable of securing the desired strength and signal transmission performance, but having improved lateral pressure resistance, bending resistance, and twist resistance. An object is to provide an excellent optical fiber cable.

[0005]

In order to achieve the above object, the present invention has the following configuration.

That is, in the optical fiber cable according to the first aspect of the present invention, the optical fiber wire is covered with an internal resin coating layer, the resin coating layer is covered with a high-tensile fiber layer, and the outside is covered with an external resin coating layer. It is characterized by having.

A cable according to a second aspect of the present invention is the cable according to the first aspect, wherein a plurality of the optical fiber wires are twisted, and a high-tensile fiber layer is provided at the center of the optical fiber wire group. It is.

According to the structure of the first aspect of the present invention, the high-tensile fiber layer that provides strength against tension is more flexible than a tension member made of a steel wire wire rope or the like, and is resistant to large bending and twisting. To respond without difficulty. In addition, since the high-tensile fiber layer elastically covers the optical fiber line via the internal resin coating layer, the optical fiber line hardly undergoes physical deformation. Further, the high tension fiber layer itself is covered and protected by the outer resin coating layer.

According to the second aspect of the present invention, the high tensile strength fiber layer located at the center of the optical fiber line group increases the tensile strength.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an external perspective view of an optical fiber cable 1 according to the present invention, and FIG. 2 is a longitudinal front view thereof.

In this optical fiber cable 1, a plurality (four in this example) of optical fiber cords 2 are twisted as optical fiber wires, and these optical fiber cords 2 are covered with an internal resin coating layer 3 made of a flexible PVC sheath or the like. While being covered, the inner resin coating layer 2 is covered with a high-tensile fiber layer 4 made of Kepler fiber, aramid fiber, or the like, and an outer resin coating layer 5 made of a resin material having excellent abrasion resistance, such as polyurethane, on the outside thereof. Covered with.
A high-tensile fiber layer 6 is also provided at the center of the optical fiber cord 2 group.

The present invention can be implemented in the following modes.

(1) It is also possible to adopt a single-wire specification in which one optical fiber cord 2 is covered with an inner resin coating layer 3, a high-tensile fiber layer 4, and an outer resin coating layer 5.

(2) In the above embodiment, the optical fiber cord 2 in which the optical fiber core 2a is covered with the vinyl sheath 2b is exemplified as an optical fiber, but the optical fiber core 2a itself is an optical fiber. It is also possible to use a configuration in which the wire is covered with the inner resin coating layer 3, the high-tensile fiber layer 4, and the outer resin coating layer 5.

(3) In the above embodiment, the high-tensile fiber layer 6 is provided also at the center of the optical fiber cord 2 group. However, the high-tensile fiber layer 4 is provided at the center of the optical fiber cord 2 group. Alternatively, an optical fiber cable can be configured.

[0017]

As is apparent from the above description, according to the present invention, the following effects can be expected.

According to the first aspect of the present invention, the high tensile strength function is obtained by using the cylindrical high-tensile fiber layer.
Compared to the case of using a tension member consisting of a steel stranded wire rope, the lateral pressure resistance, bending resistance, and twisting resistance can be improved, and it can be effectively used particularly as an optical fiber cable for transportation. it can.

Further, according to the second aspect of the present invention, the tension resistance function can be further enhanced, and the above-mentioned effect of the first aspect of the present invention is promoted.

[Brief description of the drawings]

FIG. 1 is an external perspective view of an optical fiber cable according to an embodiment of the present invention.

FIG. 2 is a vertical sectional front view of the optical fiber cable of the embodiment.

FIG. 3 is a vertical sectional front view of a conventional optical fiber cable.

[Explanation of symbols]

 2 Optical fiber line 3 Inner resin coating layer 4 High tensile fiber layer 5 External resin coating layer 6 High tensile fiber layer

Claims (2)

[Claims] 1. An optical fiber cable comprising an optical fiber line covered with an internal resin coating layer, the resin coating layer covered with a high-tensile fiber layer, and the outside covered with an external resin coating layer. 2. The optical fiber cable according to claim 1, wherein a plurality of the optical fiber wires are twisted, and a high-tensile fiber layer is provided at the center of the optical fiber wire group.