JPS6131455Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a support device for a covered wire in a power transmission and distribution line that supports the covered wire without fear of breakage due to follow-on arcs.

When an impact overvoltage such as a lightning surge occurs in a power transmission/distribution line in which a covered wire is supported by an insulator body attached to a grounding metal fitting such as a grounding arm, when an impact overvoltage such as a lightning surge occurs in the covered wire, the insulation coating of the covered wire is penetrated and the core wire and ground are grounded. A flash occurs between the wire and the metal fittings, and the core wire melts and breaks due to the arc heat of the subsequent arc. Therefore, a line-side horn that is electrically connected to the core wire of the insulated wire is attached to the head of the insulator body, and a ground-side horn is provided opposite to the tip of the line-side horn to prevent flashing from the insulated wire. Although this method prevents disconnection by flashing between the line and the earth horn without causing a circuit, it does not have the ability to limit or interrupt follow-on arcs, and in this way, the core wire of the covered wire and the electrical To attach the line-side horn that is connected to the head of the insulator body, be sure to strip off part of the insulation coating of the insulated wire, hold this core wire part in the clamp fitting, and then remove the insulation coating from the clamp fitting as well. Because the electric wire must be supported by the head of the insulator body,
It is necessary to protect the area around the clamp fittings with an insulating cover to prevent electric shock, and not only is this process time-consuming, but even if an insulating cover is used, there is a risk of flash-circuiting caused by birds as a medium. ,
There was also a risk that the core wire would undergo stress corrosion and breakage due to water seepage from the part where the insulation coating was stripped off. Furthermore, it is troublesome to attach or replace the horn on the line side to the existing insulator body, and there are various other problems such as these operations cannot be performed with a live line, and it is necessary to temporarily turn off the power.

The present invention has been completed with the aim of providing a support device for covered electric wires in power transmission and distribution lines that solves the above-mentioned problems.The present invention will be described in detail below with reference to the illustrated embodiments.

A wire receiving groove 3a is provided around the head 3 of a tight-tipped insulator body 2, which is attached to a grounding fitting 1 such as a grounding arm with a mounting fitting 9 at one end, and a covered electric wire 4 is insulated. The electric wire receiving groove 3a is directly inserted into the electric wire receiving groove 3a without removing the electric wire 4b, and the electric wire 4b is fixedly supported by the head 3 with the bind wire 5. Reference numeral 6 denotes a current-limiting element provided between the insulated wire 4 and the grounding fitting 1, and the current-limiting element 6 is made of silicon carbide, zinc oxide, etc. with nonlinear voltage-current characteristics in the insulating coating 6d of butyl rubber, etc. A current-limiting element 6a made of a material and a current-side electrode 6b and a ground-side electrode 6c that are brought into close contact with each other are built in, and only the ends of the current-side electrode 6b and the ground-side electrode 6c are communicated with the outside. A loop-shaped discharge electrode 6b' is connected to the end of the current-applying side electrode 6b, and a support fitting 8 is connected to the ground electrode 6c. The current limiting element 6 is held around the periphery of the mounting bracket 9 which is electrically connected to the grounding bracket 1 by means of a band bracket 10 connected to the support bracket 8, so that the grounding electrode 6c A loop-shaped discharge electrode 6b' connected to the current-applying side electrode 6b of the current limiting element 6 surrounds the upper part of the insulator body 2 in an annular shape at a predetermined distance and is supported by the binding wire 5. A predetermined air gap is formed between the covered electric wire 4 and the covered electric wire 4, and
The grounding metal fitting 1 is placed parallel to the covered electric wire 4 so as to be covered. In addition, 11 is a loop-shaped emission electrode 6
This is a missing portion that allows the covered wire 4 to pass through with the bind wire provided at b'.

With this structure, the covered electric wire 4 is properly supported by the head 3 of the insulator body 2 attached to the grounding fitting 1 without exposing the core wire 4a. When a lightning surge overvoltage occurs in the covered wire 4 due to a lightning strike, it will penetrate the insulation coating 4b of the covered wire 4 and cause a flash fault. Since the emission electrode 6b' is provided parallel to the covered electric wire 4, even if the covered electric wire 4 is arranged at an arbitrary horizontal angle at the gripping point, the two places of the loop-shaped emission electrode 6b' and the covering An air gap of approximately the same width is formed between the wire 4 and the electric wire 4, and therefore, this flash fault is accurately captured by the loop-shaped discharge electrode 6b' and the ground-side electrode 6c which is grounded.
Furthermore, the loop-shaped discharge electrode 6b' surrounding and protecting the insulator body 2 has an excellent trapping function even in the case of an irregular covered wire route caused by the installation of a pole. Moreover, in the present invention, the energizing side electrode 6 following this loop-shaped emission electrode 6b'
Since the current-limiting element 6 is constructed by interposing the current-limiting element 6a made of a material with non-linear voltage-current characteristics between the ground electrode 6c and the ground-side electrode 6c, the current-limiting element 6a
Due to the non-linearity of the voltage-current characteristics, insulation is quickly restored, follow-on current is blocked and no follow-on arc occurs.
Therefore, it is possible to appropriately prevent the covered electric wire 4 from melting and breaking, and from breaking the insulator due to follow-on arc. Moreover,
Since the insulated wire 4 is supported by the head 3 of the insulator body 2 without stripping off the insulation coating 4b at all, the energized part is not exposed at all, and therefore an insulating cover for protecting the energized part cannot be used. In addition, there is no risk of flash flash caused by birds as a medium, and furthermore, since the core wire 4a is not exposed at all, rainwater etc. will not penetrate, and therefore the core wire 4a will not be subject to stress corrosion. There is no risk of disconnection. Moreover, the pole installation work involves installing a current limiting element 6 that grounds the ground side electrode 6c between the covered wire 4 and the grounding metal fitting 1, and fixing and supporting the covered wire 4 to the head 3 of the insulator body 2 with a bind wire 5. The work process is small and simple because all you have to do is to connect the wire to the wire, and since the loop-shaped emission electrode 6b' is provided with a cutout 11 that allows the covered wire 4 to pass through with the bind wire 5 still attached, it is easy to use for existing power lines. This also has the advantage that the work can be carried out using live power lines without any power outages, and the work can be continued as is, without touching the energized parts.

Therefore, the present invention has great practical value as it solves the problems of supporting devices for covered electric wires in conventional power transmission and distribution lines.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view showing an embodiment of the present invention, and FIG. 2 is a partially cutaway plan view of the present invention. 1... Grounding metal fitting, 2... Insulator body, 3... Head, 4... Covered electric wire, 5... Bind wire, 6...
Current-limiting element, 6a...Current-limiting element, 6b...Electrifying side electrode, 6b'...Loop-shaped discharge electrode, 6c...Grounding side electrode, 11...Missing part.

Claims (1)

[Scope of utility model registration request] Head 3 of insulator body 2 attached to grounding fitting 1
The covered electric wire 4 is supported by a binding wire 5, and a current limiting element 6 having a built-in current limiting element 6a made of a material with non-linear voltage and current characteristics is installed between the covered electric wire 4 and the grounding fitting 1. The loop-shaped discharge electrode 6b' is connected to the ground via the grounding electrode 6c, and the current-limiting electrode 6b of the current limiting element 6a has a cutout 11 that allows the covered wire 4 to pass through with the binding wire attached. A support device for a covered electric wire in a power transmission/distribution line, characterized in that the insulator body 2 is surrounded by the insulator body 2 and the insulator body 2 is continued so as to form an air gap between the insulator body 2 and the covered electric wire 4.