JPH08212836A - Self-supporting cable and its construction method - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is not only to effectively suppress the inconvenience caused by vibration distortion applied to a self-supporting cable, but also to achieve a reduction in the installation work cost and a shortened construction period. It is to provide a new self-supporting cable that can be used and a construction method thereof. According to the present invention, in a self-supporting cable in which a cable conductor 1 and an auxiliary support wire 6 are arranged in parallel, and the cable conductor 1 and the auxiliary support wire 6 are integrally covered with an insulating coating 3, It is characterized in that a plurality of slit portions 7 extending in the length direction of the support wire 1 are formed in the cover 3 between the auxiliary support wire 6 at predetermined intervals.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-supporting cable in which a cable conductor and a supporting wire are integrally covered with an insulating material such as polyethylene, and a construction method thereof.

[0002]

2. Description of the Related Art Generally, an electric wire / cable called a self-supporting cable is formed by covering a cable conductor 1 and a supporting wire 2 with an insulator 3 such as polyethylene and integrating them as shown in FIG. Yes, as shown in FIG. 4, after being installed in the field, a plurality of overhead wire fittings 4 ...
Thus, the entire cable is fixedly installed every 3 to 5 m. However, in such an erection method, when the cable is laid under adverse conditions such as along the railway where many vibrations occur, distortion due to cable vibration concentrates at the end of each overhead wire fitting 4, ... Injuries such as cracks may be scattered on the support line 2. Therefore, the overhead wire at the place where such vibration occurs uses the double messenger wire method as shown in FIG. In this double messenger wire construction method, an auxiliary messenger wire 5 made of copper stranded wire or the like is pre-wired at a position where a cable is to be laid, and only the cable support wire 2 is attached to the auxiliary messenger wire 5 by a plurality of overhead wire fittings. This is a construction method that reduces vibration distortion by fixing with 4.

[0003]

However, in such a double messenger wire construction method, since it is necessary to lay the auxiliary messenger wire 5 and the cable, it is troublesome to lay the wire, and the construction cost rises and the construction period increases. It was unavoidable for the long term.

Therefore, the present invention has been devised to solve the above problems, and its purpose is not only to effectively suppress the inconvenience caused by the vibration distortion applied to the self-supporting cable, but also to perform the laying work. It is an object of the present invention to provide a novel self-supporting cable that can reduce the cost and the construction period, and a method of constructing the same.

[0005]

To achieve the above object, the present invention provides a self-supporting device in which a cable conductor and an auxiliary supporting wire are arranged in parallel, and the cable conductor and the auxiliary supporting wire are integrally covered by an insulating coating. In the type cable, a plurality of slit portions extending in the lengthwise direction of the auxiliary supporting wire are formed at predetermined intervals in a covering body between the cable conductor and the auxiliary supporting wire, and the self-supporting In the method of constructing the type cable, the substantially central portion of each slit formed on the self-supporting type cable is held by the wire fitting to the fixed portion.

[0006]

According to the present invention, the self-supporting cable having the above-mentioned structure is used, and the substantially central portion of each slit formed in the self-supporting cable is held by the overhead wire fitting, so that the cable itself is provided. Even if vibration is applied to
By deforming the slit portion so as to bend vertically, the distortion due to the vibration is dispersed around the slit portion. Therefore, unlike the conventional case, the strain due to vibration is not concentrated on the end portion of each overhead wire fitting, and it is possible to prevent damage such as cracks in the cable conductor or the support wire in that portion. Moreover, unlike the conventional double messenger construction method, the construction method of the present invention does not require the auxiliary messenger wire to be installed in advance, so that the construction work cost and the construction period can be shortened.

[0007]

An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows a self-supporting cable A according to the present invention.
FIG. As shown in the figure, in this self-supporting cable A, the cable conductor 1 and the supporting wire 2 and the auxiliary supporting wire 6 are arranged in parallel on the same plane with a predetermined space therebetween, and the cable conductor 1 The support wire 2 and the auxiliary support wire 6 are integrally formed with an insulating cover 3 such as polyethylene. As the auxiliary supporting wire 6, for example, a steel stranded wire obtained by twisting seven steel wires having a diameter of 2.6 mm, or a FRP having a tensile strength equivalent to that of the steel stranded wire
Use twisted wires. In addition, in the covering body between the cable conductor 1 and the auxiliary supporting wire 6 (the insulating covering body 3 connecting the supporting wire 2 and the auxiliary supporting wire 6 or the covering body between the cable conductor 1 and the supporting wire 2) A plurality of slit portions 7 extending in the length direction of the support line 2 are formed at predetermined intervals, and each slit portion 7 has appropriate elasticity and is deformable.

As shown in FIG. 1, the self-supporting cable A having such a structure is positioned so that the side of the auxiliary support line 6 is in the top direction and the side of the cable conductor 1 is in the direction of the ground, and each of these slit portions is arranged. Approximately the center of 7 is the overhead wire fitting 4 ...
Install it so that it will be held by the fixed part.

When vibration is applied to the self-supporting cable A laid in this way, the vibration causes the slits 7
Is deformed so that it opens and closes up and down, and the vibration strain is dispersed and absorbed by the insulating coating 3 around each slit 7. Therefore, injuries such as cracks in the insulating cover 3 at the ends of the overhead wire fittings 4 that directly support the auxiliary support wire 6 as well as the cable conductor and the support wire 2 are prevented. Further, in this self-supporting cable A, since the auxiliary supporting wire 6 corresponding to the conventional auxiliary messenger wire is integrated with the cable conductor 1 and the supporting wire 2 by the insulating coating 3, like the conventional double messenger method, It is not necessary to wire the auxiliary messenger wire in advance, which facilitates installation work.

Further, the present invention may be configured such that the above-mentioned support line 2 is eliminated as shown in FIG. 2 and the auxiliary support line 6 is used as the support line corresponding to FIG. Similar to the embodiment, the insulating coating 3 at the end of each overhead wire fitting 4 ...
Although it is slightly inferior in strength as compared with the above-mentioned embodiment, of course, it is possible to reduce the labor for laying work and the manufacturing cost of the cable itself as well as preventing damage such as cracks.

[0012]

In summary, according to the present invention, it is of course possible to prevent damage such as cracks in the cable conductor or the support wire due to vibrations, and also to wire the auxiliary messenger wire in advance as in the conventional double messenger method. Since it is not necessary to keep it in advance, it has excellent effects such as drastically reducing the construction cost and shortening the construction period.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of a cable of the present invention.

FIG. 2 is a side view showing a modified example of the cable of the present invention.

FIG. 3 is an enlarged cutaway perspective view showing a conventional typical self-supporting cable.

FIG. 4 is a side view showing a conventional self-supporting cable and a construction example thereof.

FIG. 5 is a side view showing an example of installation using a conventional double messenger wire method.

[Explanation of symbols]

 1 Cable conductor 2 Support wire 3 Insulation cover 4 Overhead metal fitting 5 Auxiliary messenger wire 6 Auxiliary support wire 7 Slit part

Claims (2)

[Claims] 1. A self-supporting cable in which a cable conductor and an auxiliary support wire are arranged in parallel, and the cable conductor and the auxiliary support wire are integrally covered with an insulating coating, and the cable conductor and the auxiliary support wire are provided between the cable conductor and the auxiliary support wire. A self-supporting cable, characterized in that a plurality of slit portions extending in the length direction of the auxiliary supporting wire are formed at a predetermined interval in the covering body. 2. The method for constructing a self-supporting cable according to claim 1, wherein the substantially central portion of each slit portion formed in the self-supporting cable is retained by a wire fitting to a fixed portion. Construction method for self-supporting cables.