JPH0261084B2 - - Google Patents

Description

[Detailed Description of the Invention] Nowadays, optical fiber cables can transmit a large amount of information, have low loss, and are non-inductive insulators, so when used in combination with power transmission lines, they can be used in combination with conventional power line transport and , which is attracting attention because it can transmit large amounts more reliably than microwave communication.

In the case of power transmission lines, considering various circumstances, optical fibers are incorporated into overhead ground wires and used for purposes such as transmitting information between substations, transmitting information on power transmission lines, and countermeasures against television interference. However, optical cables used for this purpose are either built into a cavity in which one of the strands of the overhead ground wire is removed, or the overhead ground wire is constructed as an expanded type with an internal cavity. The idea is to incorporate it there. As a result of extensive research, the inventors created an optical composite overhead ground wire in which a non-adhesive intermediate layer was provided between a composite wire consisting of an optical fiber with a silicone polymer surface layer and a high tensile strength wire, and a silicone polymer sheath. Ta.

That is, the optical composite cable incorporated in the overhead ground wire of the present invention (1) has an extremely small application space, so it is necessary to reduce the diameter accordingly, but in order to reduce the diameter, it is necessary to gather optical fibers together. Therefore, it is necessary to prevent the occurrence of local bending or deformation due to the external force at that time, but such bending or deformation does not occur due to the presence of the high tensile strength wire.

(2) Thermal safety is guaranteed because silicone polymer is used for the sheath and other coverings. In particular, a silicone polymer is used in the primary coat that directly coats the optical fiber to protect the optical fiber, and the silicone sheath has the effect of further protecting them, but since a non-adhesive intermediate layer is provided between the two, If this non-adhesive intermediate layer were not present, the inner and outer silicone polymer layers of the same type would adhere during the manufacturing process of the optical cable, which would easily cause the alignment of the optical fibers to become distorted, resulting in increased loss of the optical fibers. ,
In the present invention, such a problem does not occur and excellent transmission characteristics can be exhibited.

Here, the non-adhesive intermediate layer is a coating or coating layer of nylon, fluorine resin, talc, etc.
This is a preferable material from the viewpoint of required thermal conditions and manufacturing.

Next, this invention will be explained with reference to the drawings.
FIG. 1 shows an embodiment of the present invention, in which six optical fibers 2 each having a primary coat 3 of silicone rubber around a high tensile strength wire 1 such as a piano wire or carbon fiber are arranged on the same circumference. A non-adhesive intermediate layer 4 such as nylon or fluororesin and a silicone resin sheath 5 are provided to cover them all together.

FIG. 2 shows another embodiment of this invention, in which a piano wire,
Six stripes of optical fibers 2 are arranged on the same circumference at appropriate intervals around a high tensile strength wire 1 such as a carbon fiber, and a silicone rubber layer 3 is provided to fill the voids and cover the whole. A silicone resin sheath 5 is then provided via a non-adhesive intermediate layer 4 of talc, nylon, fluorine resin, or the like. The difference between FIG. 1 and FIG. 2 is whether the optical fibers are individually coated with silicone rubber or collectively coated with silicone rubber, and the rest are the same.

Therefore, as mentioned above, the cables of these embodiments have a relatively small diameter, the presence of high tensile strength wires does not cause local bending or deformation of the optical fiber, and the presence of a non-adhesive intermediate layer allows for internal and external connections. This is an optical composite cable that prevents adhesion of silicone polymer, does not cause disruption of the alignment of optical fibers at the time of cross-linking of the sheath, and has extremely low optical fiber loss.

[Brief explanation of drawings]

The figures are cross-sectional views showing embodiments of the present invention; FIG. 1 shows a case in which optical fibers are individually coated with silicone polymer, and FIG. 2 shows a case in which optical fibers are commonly coated with silicone polymer. 1... High tensile strength wire, 2... Optical fiber, 3...
Silicone polymer, 4... Non-adhesive intermediate layer, 5...
...Silicone polymer sheath.

Claims (1)

[Claims] 1. An optical composite characterized in that a non-adhesive intermediate layer is provided between a composite wire consisting of an optical fiber having a silicone polymer surface layer and a high tensile strength wire and a silicone polymer sheath. Overhead ground wire optical cable. 2. A composite wire consisting of an optical fiber having a surface layer of silicone polymer and a high tensile strength wire is constructed by arranging a plurality of optical fibers individually coated with silicone polymer around the high tensile strength wire. An optical composite overhead ground wire optical cable according to claim 1. 3. A composite wire consisting of an optical fiber with a surface layer of silicone polymer and a high tensile strength wire, with multiple optical fibers evenly distributed around the high tensile strength wire, and these voids are filled with silicone polymer. The invention according to claim 1 is covered all at once while fulfilling the following.