JPS61184503A - Method of stringing light composite overhead earth wire - Google Patents

Abstract

PURPOSE:To prevent disconnection of optical fiber by not fixing an overhead earth wire and core of optical fiber on one end and making stringing with the end of the overhead earth wire covered by a cap. CONSTITUTION:On both ends of an overhead earth wire 1, an overhead earth wire 2 and core 3 of optical fiber are not fixed and kept free, and the overhead earth wire 2 is covered by a cap 5. The cap 5 is made of, for instance, plastics of rubber, and fixed to the overhead earth wire 2 by tape winding or bonding. As the core 3 of optical fiber is free on both ends to the overhead earth wire 2 at the time of stretching and tightening the wire, tension acts hardly, and elongation of the overhead earth wire does not take place. Thus, there is no fear of disconnection of optical fiber, and slipping out from the overhead earth wire 2 does not occur at the time of stringing.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a method for overhead wiring (extension/tensioning) of open ground wires.

[Prior art and its problems]

Recently, in order to perform optical communications using overhead power transmission lines, optical composite overhead ground wires have been developed, in which a hole is made in the overhead ground wire (usually at its center) and an optical fiber core is housed in the hole. It is being used. In this type of optical composite overhead ground wire, the optical fiber is loosely housed in the hole in the overhead ground wire in order to handle breakage of the optical fiber or replacement of the optical fiber after installation. Only the fiber core can be exchanged. Note that as the optical fiber coated wire, an FRP coated optical fiber coated wire having high strength and excellent heat resistance is usually used.

However, in the above structure, since the optical fiber core wire is movable within the overhead ground wire, the optical fiber core wire may be pulled out from the overhead ground wire when the overhead wire is installed. In order to prevent this, in the past, as shown in Figure 2, wires were placed at both ends of the optical composite overhead ground wire (1). They were hardened and integrated with Resin 4, and overhead lines were installed in this state.

However, when the wire is stretched or stretched, a large tension is applied, and the metal overhead ground wire 2 undergoes relatively large elastic elongation, so both ends are fixed to the overhead ground wire 2. A large elongation strain is also applied to the optical fiber core 3. For this reason, the conventional overhead wire method has a problem in that the optical fiber is likely to break.

[Means for solving problems and their effects]

In order to solve the problems of the prior art as described above, the present invention provides a method for wiring an optical composite overhead ground wire, which is formed by loosely storing an optical fiber core in a hole provided in an overhead ground wire, on a steel tower. , characterized in that at least one end side of the optical composite overhead ground wire is connected with the overhead ground wire and the optical fiber core wire not fixed, but with a cap covering the end of the overhead ground wire. be.

In this way, even if the overhead ground wire stretches due to the tension applied to the overhead wire, that stretch will not be applied to the optical fiber core wire.
Not only can the optical fiber be prevented from breaking, but also the optical fiber core can be prevented from being pulled out.

〔Example〕

Prior to overhead line construction, as shown in Figure 1, both ends of the optical composite overhead ground wire 1 are left free without fixing the overhead ground wire 2 and the optical fiber core 3, and caps 5 are attached to the overhead ground wire 2. Leave it covered. This cap 5 is made of plastic or rubber, and is fixed to the overhead ground wire 2 by wrapping with tape or gluing. Although not shown in the drawings, the optical composite overhead ground wire 1 with caps 5 on both ends is wound around a drum and transported to a construction site, where it is extended onto a steel tower and further wire tensioned. When the cable is stretched or stretched, a large amount of tension is applied to the overhead ground wire 2, causing it to stretch.However, since both ends of the optical fiber core 3 are free with respect to the overhead ground wire 2, no tension is applied to it and it does not stretch. Does not occur. Therefore, there is no risk of the optical fiber breaking. Further, even if both ends of the optical fiber core 3 are free, since it is covered with the cap 5, there is no need to pull it out from the overhead ground wire 2 when connecting the optical fiber.

In the above example, the overhead ground wire and the optical fiber core were not fixed at both ends, and the ends of the overhead ground wire were covered with caps, but one end was as described above, and the other end was Similarly, the overhead ground wire and the optical fiber core may be fixed.

〔Effect of the invention〕

As explained above, according to the present invention, when connecting an optical composite overhead ground wire, the optical fiber core wire does not undergo large elongation, and the optical fiber core wire does not come out from the overhead ground wire. , since it can be used as an overhead wire, it has the advantage of significantly improving the reliability of overhead line work for optical composite overhead ground wires.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway front view showing the end structure of the optical composite overhead ground wire before the overhead wire in the overhead wire method of the present invention, and FIG. 2 is the end of the optical composite overhead ground wire before the overhead wire in the conventional overhead wire method. It is a partially cutaway front view showing the structure. 1 ~ Optical composite overhead ground wire, 2 ~ Overhead ground wire, 3 ~ Optical sofa No. 1 Figure 2

Claims (3)

[Claims] (1) In a method of overheading an optical composite overhead ground wire, which is formed by loosely storing an optical fiber core wire in a hole provided in an overhead ground wire, on a steel tower, at least one end side of the optical composite overhead ground wire is connected to the above-mentioned overhead ground wire. An overhead wiring method for an optical composite overhead ground wire, characterized in that the overhead wiring is carried out with a cap placed on the end of the overhead ground wire without fixing the line and the optical fiber core wire. (2) The overhead wire method according to claim 1, comprising:
The other end of the optical composite overhead ground wire is also connected without fixing the overhead ground wire and the optical fiber core wire, but with a cap placed over the end of the overhead ground wire. (3) The overhead wire method according to claim 1,
The other end of the optical composite overhead ground wire is connected with the overhead ground wire and optical fiber core wire fixed.