JPH0736666B2 - Wire grip - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric wire gripping portion in an overhead power transmission line or the like, and more particularly to a so-called armor grip type electric wire gripping portion such as a spacer, a damper or a twist prevention device.

[0002]

2. Description of the Related Art As an electric wire gripping portion of this kind, a metal engaging portion (usually aluminum) which engages with an electric wire and inner and outer surfaces of the engaging portion are found, for example, as disclosed in Japanese Utility Model Laid-Open No. 49-137095. An electric wire gripping body composed of a covered rubber-like elastic body is engaged with the electric wire, and a plurality of helical rods such as armor rods (usually aluminum) are wound around the outer circumference of the electric wire gripping body and gripped and fixed to the electric wire. Wire grips are known. The rubber-like elastic body has a function of preventing contact wear between the metal engaging portion and the electric wire and preventing vibration of the electric wire.

However, the metal engaging portion and the electric wire engaging the metal engaging portion are in contact with each other via the rubber-like elastic body, and the electric resistance of the rubber-like elastic body is generally 100 Ω to 2 MΩ.
In addition to the above, since the thickness of the rubber-like elastic body is 2.5 mm to 1.0 mm, the following problems occur.

That is, galloping vibration, vibration such as street jump, etc. occur in the electric wire to be grasped, for example, the electric wire of phase A,
When an electric wire of another phase, for example, a B phase, comes into contact with a portion of the spacer body that is electrically connected to the metal engaging portion and causes a short circuit between phases, the B phase current is generated by the spacer body-metal engaging portion. −
Rubber-like elastic body-flows into the A-phase electric wire.

[0005]

Generally, in such a case, the circuit breaker operates and the current is cut off within about 0.1 to 0.75 seconds, but the current flowing through the electric wire is usually 20 KA or more, which is the above. It will flow within the operating time of the circuit breaker. The thickness of the rubber-like elastic body is 2.5 mm to 1.0 mm
Therefore, there is a possibility that local arc discharge may occur between the metal engaging portion and the electric wire, and the electric wire may be fused.

[0006]

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention is a so-called armor grip type wire grip in which a local arc discharge does not occur even when a current of a wire of another phase flows in a metal engaging portion. It is intended to provide a section.

In order to achieve the above-mentioned object, the present invention has the following structure. That is, the present invention provides an electric wire gripping body composed of a metal engaging part that engages with an electric wire and a rubber-like elastic body covering the inner and outer surfaces of the engaging part, and a rubber-like elastic body on the outer periphery of the electric wire gripping body. With a helical rod wound from above on the electric wire, in the electric wire gripping part that is gripped and fixed to the electric wire, further comprising a conductive helical rod that electrically brings the metal engaging part and the electric wire to the same potential, The conductive helical rod is characterized in that it is wound around the electric wire from the metal engaging portion exposed from the end of the rubber-like elastic body coated on the outer surface of the metallic engaging portion. is there.

[0008]

According to the present invention, since the conductive helical rod is wound around the metal engaging portion exposed from the end of the rubber-like elastic body covering the outer surface of the metal engaging portion, the electric wire is Even if the multi-phase electric wire vibrates and contacts the spacer frame, the arm of the anti-twist device, etc., and this multi-phase electric current flows to the metal engaging part, it flows to the electric wire to be grasped via the rubber-like elastic body. This is extremely rare, and most of them flow to the wire to be grasped via the helical rod, and local arc discharge hardly occurs between the metal engaging part and the grasped wire, and the wire may be melted or cut. Disappear.

Moreover, since the rubber-like elastic body is interposed between the electric wire and the metal engaging portion and between the metal engaging portion and the helical rod, vibration suppression of the electric wire and the metal engaging portion are performed. The contact wear between the wire and the electric wire or the helical rod can be prevented.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG.
The drawings are cross-sectional views of the essential parts showing an embodiment of the present invention. In the figure, 1 is an electric wire, 8 is a spacer frame, and 2 is an electric wire gripping body movably protrudingly provided on the spacer frame 8.

The wire gripping body 2 includes a pedestal 9 projecting from the spacer frame 8 and an arm 3 having a base movably mounted on the pedestal 9 and a metal engaging portion 4 for engaging the electric wire 1 on an upper portion thereof. , A rubber-like elastic body 5 covering the inner and outer surfaces of the metal engaging portion 4. As shown in FIG. 1, the electric wire gripping body 2 configured in this manner engages the metal engaging portion 4 covering the rubber-like elastic body 5 with the electric wire 1 and a plurality of electric wire gripping bodies 2 from the outer periphery of the electric wire gripping body 2. The helical rod 6 is wound around the electric wire 1 and gripped and fixed to the electric wire 1 to form an electric wire grip portion.

Reference numeral 7 in FIG. 1 denotes a conductive helical rod in which the electric wire 1 and the metal engaging portion 4 are electrically connected to each other so that they have the same potential. Both ends of the conductive helical rod 7 are wound around the electric wire 1, and an intermediate portion of the conductive helical rod 7 is made of metal.
It is wound around the metal engaging portion 4 exposed from the end of the rubber-like elastic body 5 covering the outer surface of the. Therefore, the electric wire 1 and the metal engaging portion 4 are at the same potential via the conductive helical rod 7. The present invention can also be applied to a damper.

[0013]

As described above, the present invention provides an electric wire gripping body comprising a metal engaging portion for engaging an electric wire and a rubber-like elastic body covering the inner and outer surfaces of the engaging portion. A helical rod wound around an electric wire from the rubber-like elastic body on the outer periphery of the grip body, and in the wire grip portion gripped and fixed to the wire, the metal engaging portion and the wire are electrically conductive to have the same electric potential. The conductive helical rod is further wound, and the conductive helical rod is wound around the electric wire from the metal engaging portion exposed from the end of the rubber-like elastic body coated on the outer surface of the metal engaging portion. Therefore, even if the electric wire vibrates and the polyphase electric wire comes into contact with the spacer frame, the arm of the anti-twist device, etc., and this polyphase electric current flows to the metal engaging part,
It rarely flows to the electric wire to be grasped via the rubber-like elastic body, and most of it flows to the electric wire to be grasped via the conductive helical rod. Therefore, a local arc discharge hardly occurs between the metal engaging portion and the electric wire to be grasped, so that the electric wire is not melted.

Moreover, since the rubber-like elastic body is interposed between the electric wire and the metal engaging portion and between the metal engaging portion and the helical rod, vibration suppression of the electric wire and the metal engaging portion are performed. The contact wear between the wire and the electric wire or the helical rod can be prevented.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part showing an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric wire 2 Electric wire gripping body 3 Arm 4 Metal engaging portion 5 Rubber-like elastic body 6 Helical rod 7 Conductive helical rod 8 Spacer frame 9 Pedestal

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Bibliographic references Sho 58-626 (JP, U)

Claims (1)

[Claims] 1. An electric wire gripping body comprising a metal engaging part for engaging with an electric wire and a rubber-like elastic body coated on the inner and outer surfaces of the engaging part, on a rubber-like elastic body on the outer periphery of the electric wire gripping body. A helical rod wound from the electric wire to the electric wire, in the electric wire gripping portion gripped and fixed to the electric wire, further comprising a conductive helical rod for electrically setting the metal engaging portion and the electric wire to the same electric potential. The conductive helical rod is wound around the electric wire from the metal engaging portion exposed from the end of the rubber-like elastic body coated on the outer surface of the metal engaging portion to the electric wire gripping portion. .