JPH0515021A - Bypass cable work method and clamp used for it - Google Patents

Abstract

PURPOSE:To easily lay a bypass cable between it and an adjacent underground cable by attaching a live wire clamp to the barrel of the connector at the terminal connection between a high voltage insulated cable and an underground power cable. CONSTITUTION:The lines are branched from the branch parts 3 and 3' of a high voltage insulated cable 1 and are connected to the switches 2 and 2' on a utility pole through connection wires 6 and 6'. On the other hand, the connectors 4 and 4' of underground cables 5 and 5' and the terminals of the switches 2 and 2' are connected with each other through live wire clamps 7 and 7. The live wires 7 and 7' are equipped, at the barrel, with handles, receiving metal fittings, press metal fittings, braid conductors, etc., omitted from the figure, and bypass cables 10 are mounted or removed by rotating the handles. This obviates the exfoliation and the repair of the insulating cover of the high voltage insulated cable, and confines the exposed charge part to the indispensable minimum, and a hot-line work using an insulating globe can be done easily.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bypass cable construction method for an overhead high voltage distribution line and a hot wire clamp used therefor.

[0002]

2. Description of the Related Art The bypass cable construction method is carried out when the overhead high-voltage distribution line is replaced while the equipment is replaced or the branch line is pulled out while the overhead high-voltage distribution line is live (uninterrupted). FIG. 3 is an explanatory diagram of a conventional bypass cable construction method. Remove the coating of the high-voltage insulated electric wire 1 as a overhead high-voltage distribution line at two locations with a predetermined distance, using a live-wiring tool, and attach the live cable to both ends of the bypass cable 10 at those locations. The wire clamp 21 was attached using jigs or insulating gloves to form a bypass cable. After the completion of predetermined work such as replacement of equipment and extraction of branch lines, the live wire clamp 21 is removed from the insulated wire 1, the bypass cable 10 is removed, and an insulating tape and a protective tape are attached to the places where the coating is stripped off. It was wrapped around and restored to the old state. Reference numeral 22 is an intermediate switch provided in the middle of the bypass cable 10.

In the above-mentioned conventional bypass construction method,
Since the clamp is attached by peeling off a part of the coating of the high voltage insulated wire, the conductor may be damaged. Further, since the insulation is restored by winding the tape after use, there is a possibility that the reliability of the insulation performance of the high voltage insulated wire may be deteriorated.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the above problems and provides a bypass cable construction method which does not require the removal and repair of the insulation wire coating, and a clamp used therefor. The first feature thereof Is a bypass cable construction method in which a live wire clamp is attached to a connection terminal body of a terminal connection portion of an underground power cable that is connected to a high-voltage insulated electric wire, and a bypass cable is installed between adjacent terminal connection portions of the underground power cable. A second feature of the present invention is that a support metal fitting is provided at one end of a clamp body having a substantially U-shape, and a holding metal fitting facing the support metal fitting penetrates the other end of the clamp body via an outer peripheral screw. The clamp is provided at the tip of the clamp, and the receiving fitting and the pressing fitting are connected by a braided conductor.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory view of a bypass cable construction method of the present invention, and FIG. 2 is an explanatory view of a connecting portion with an underground power cable such as a CV cable. As shown in detail in FIG. 2, the high-voltage insulated electric wire 1 is connected to the switch 2 via a connecting wire 6 branched from the branch portion 3. On the other hand, an underground power cable 5 such as a CV cable is connected to the switch 2 by a terminal connecting portion 4. Therefore, the only exposed portion of the high-voltage insulated electric wire 1 is the connecting terminal 41, which is the connecting portion between the terminal connecting portion 4 of the underground power cable 5 and the switch 2. In the bypass construction method of the present invention, the live wire clamp 7 is attached to the body of the connecting terminal 41 of the terminal connecting portion 4 of the underground power cable 5 and the bypass cable 10 is installed between the adjacent terminal connecting portions 4. In this way, since the bypass cable is formed by using the connection terminal body portion of the terminal connection portion of the power cable,
No need to touch the high voltage insulated wire.

4 (a) and 4 (b) are explanatory views of a live wire clamp 7 attached to the connection terminal body of the terminating end connecting portion. FIG. 4 (a) is a top view and FIG. 4 (b) is a side view. As shown in the drawing, a dogleg-shaped receiving metal fitting 75 is fixed to one end of the clamp body 71 having a substantially U shape, and the other side is penetrated through a screw 72a provided on the outer circumference. There is a support rod 72. An inverted V-shaped pressing fitting 74 facing the receiving fitting 75 is fixed to the tip of the supporting rod, and a handle 73 for operating the supporting rod 72 is integrally provided at the rear end portion. In addition, the above-mentioned press fitting 74
Conductive rubber body 76
Are attached or integrally molded, and the holding metal fitting 74 and the receiving metal fitting 75 are connected by a braided conductor 77.
Reference numeral 78 is a terminal attachment portion of the bypass cable.

[0007]

[Function] When the handle 73 is turned by hand using an insulating glove, the support rod 72 moves forward in the left direction in the figure due to the screw action, and accordingly the holding metal fitting 74 moves toward the receiving metal fitting 75, and the distance between the two is increased. Becomes smaller. As a result, the braided conductor 76 is wound around the connection terminal body 41 of the terminal connection portion. Connection terminal body 41
In general, hexagonal compression is standard.
The shape of the inner surface of 75 matches the compressed shape of the terminal body 41. Since the shape of the terminal body 41 is not constant even though it is hexagonally compressed, the braided conductor 76 is properly wound around the terminal body 41 via the conductive rubber body 76.

[0008]

As described above, according to the bypass cable construction method of the present invention, since the bypass cable is installed by utilizing the terminal connection portion of the underground power cable, it is necessary to add any work to the high voltage insulated wire. In addition, not only the trouble of removing the coating of the high-voltage insulated electric wire and the repair thereof are unnecessary, but also the reliability thereof is not deteriorated.

Further, since the live wire clamp uses the braided conductor to wrap it around the connecting terminal body, the live wire clamp flexibly contacts the compressed shape of the connecting terminal body. In particular, by providing a conductive rubber body on the inner surfaces of the pressing fitting and the receiving fitting, the terminal body can be softly gripped.

[Brief description of drawings]

FIG. 1 is an explanatory view of a specific example of a bypass cable construction method of the present invention.

FIG. 2 is an explanatory diagram of a connection portion between a high voltage insulated electric wire and an underground power cable.

FIG. 3 is an explanatory diagram of a conventional bypass cable construction method.

FIG. 4 is an explanatory view of the clamp of the present invention.
4B is a side view. FIG.

[Explanation of symbols]

1 High voltage insulated wire 2 switch 4 Terminal connection part 41 Connection terminal 5 underground power cable 7 Live wire clamp 71 Clamp body 72 Support rod 73 handle 74 Presser bracket 75 bracket 76 Conductive rubber body 77 braided conductor

Claims (2)

[Claims] 1. A live line clamp is attached to a connection terminal body of a terminal connection portion of an underground power cable to be connected to a high-voltage insulated electric wire, and a bypass cable is installed between the terminal connection portions of adjacent underground power cables. The characteristic bypass cable construction method. 2. A receiving metal fitting is provided at one end of a clamp body having a substantially U shape, and a holding metal fitting facing the receiving metal fitting is provided at a tip of a support rod penetrating the other end of the clamp body via an outer peripheral screw, A clamp characterized in that the receiving fitting and the pressing fitting are connected by a braided conductor.