JPH0229677Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention is used in power transmission and distribution lines using insulated wires, and prevents wire breakage and insulator damage by limiting or blocking AC follow-on current caused by lightning flash faults. This invention relates to a metal bound wire with a current-limiting element unit that protects electric lines and restores insulation by itself in the event of a short circuit or short circuit to prevent power outages.

(Prior Art) A lightning disconnection prevention device for an insulated wire that prevents lightning disconnection by using a current limiting element unit equipped with a current limiting element made of a material with nonlinear voltage-current characteristics is as follows: For example, it has been proposed in Japanese Patent Application Laid-Open No. 58-38410. However, in the conventional device of this type, an insulated wire is attached with a metal binding wire to the head of an insulator attached to a grounding fitting, and a current limiting element unit is attached to the grounding fitting. In order to further improve the ability to capture lightning flash faults from insulated wires, a ring-shaped discharge electrode surrounding an insulator is attached to the current-applying side of the current limiting element unit with an air gap between it and the insulated wires. This ensures that lightning surge overvoltage always causes a flashover between the insulated wire and the discharge electrode. As a result, the entire device is large, heavy and inconvenient to handle.

Furthermore, a device in which a current limiting element unit is attached to the insulated wire side is disclosed in Japanese Utility Model Application Publication No. 57-203489, but in this example, the insulated wire is fitted onto the insulated wire with a bind wire hanging from the top of the insulator, and the insulated cover is covered. Install the
A lightning arrester connected to an insulated wire by a connector is fixed and attached to this cover. This had the disadvantage that the space above the pillars was reduced, which tended to get in the way of track inspections and repair work.

(Problems to be solved by the invention) The present invention solves the above-mentioned conventional problems and is compact, lightweight, does not require separate parts for installation, and can be easily installed on electric lines. This has been completed in order to provide a metal bound wire with a current limiting element unit that can exhibit the effect of preventing lightning disconnection.

(Means for Solving the Problems) The present invention provides voltage-current characteristics on one side of the helical gripping portion of a metal bound wire, which is provided with helical gripping portions on both sides for attaching an insulated wire to the head of an insulator. A current-limiting element unit consisting of a current-limiting element made of a non-linear material, a discharge electrode, and a energizing side electrode covered with a jacket made of an insulating material is fixed together with the energizing side electrode. It is characterized in that it is electrically connected.

(Embodiments) Next, the present invention will be described in detail with reference to illustrated embodiments.

Reference numeral 3 denotes a metal binding wire made of stainless steel wire or the like, which is used to attach the insulated wire 4 to the head of the insulator 2 supported by the grounding fitting 5. This metal binding wire 3 has spiral gripping portions 3a on both sides thereof,
3a, and an arcuate protrusion 3b extending toward the insulator head at the center, and is a preform product formed in advance in the same way as conventional metal binding wires. In the present invention, the current limiting element unit 1 is electrically connected to one side of the spiral gripping portions 3a, 3a of the metal binding wire 3 by welding or the like and is fixed integrally therewith.

The current-limiting element unit 1 has a current-limiting element 1a made of a material with non-linear voltage-current characteristics, mainly ZnO or SiC, interposed between the discharge electrode 1b and the voltage-applying side electrode 1c, and is insulated with elastic insulation such as rubber. Mantle body 1 made of material
d so that only the connecting end to the outside of the energizing side electrode 1c protrudes and is exposed, and the other discharge electrode 1b formed in a dogleg shape has only its discharge end covered by the mantle. It communicates with the outside through the opening 1d. And this charging side electrode 1c
is directly connected and fixed to the spiral gripping portion 3a of the metal binding wire 3. The fixed position of the current limiting element unit 1 is fixed at the dogleg-shaped discharge electrode 1b when installed.
is located opposite the grounding metal fitting 5 of the insulator 2, and a predetermined air gap is formed between the grounding metal fitting 5 and the discharge electrode 1b.

(Function) The metal bound wire with the current limiting element unit of the present invention configured as described above has the arcuate protrusion 3b hung on the head of the insulator 2, and the helical grips 3a on both sides of the insulated wire. 4, the insulated wire 4 is fixed to the insulator 2 by wrapping it around the insulated wire 4. At this time, as shown in FIG. The discharge electrode 1b faces the grounding metal fitting 5 of the insulator 2, and a predetermined air gap is formed between the grounding metal fitting 5 and the discharge electrode 1b.

Therefore, when the sheathing of the insulated wire 4 is penetrated and destroyed by the lightning surge overvoltage, the lightning surge is captured by the current limiting element unit 1 through the metal binding wire 3 located at a close distance, and connected to the discharge electrode 1b and grounded. The lightning impulse flashes over in the air path between it and the metal fitting 5, and the subsequent current is blocked by the non-linearity of the voltage-current characteristics of the current-limiting element 1a.
Since the generation of follow-on arcs is prevented, wire breakage and insulator damage due to follow-on arcs are prevented. Moreover, since the current limiting element unit 1 is integrally fixed and electrically connected to the metal binding wire 3, the grounding metal fitting 5
Since the discharge electrode 1b can be brought directly close to the discharge electrode 1b, it is possible to catch lightning flashes without providing a large ring-shaped discharge electrode as in the conventional method.

In this way, the metal bound wire with current limiting element unit of the present invention is small and lightweight, and easy to handle.
It also reduces the space it occupies on the pillars, giving it a simple aesthetic appearance. Furthermore, the present invention can be quickly applied to an existing electric wire support device by simply replacing the metal binding wire with the metal binding wire of the present invention, and no trouble is required for repair work.

(Effects of the invention) As is clear from the above description, the present invention is one in which a current limiting element unit is integrally fixed to one side of the spiral gripping part of the metal binding wire. By installing them close together, in the event of a lightning strike, the lightning surge is first captured by the current limiting element unit, which has the ability to interrupt the follow-on current, through the metal binding wire located close to the insulated wire, and connects the discharge electrode to the grounding metal fitting. Lightning impulse flashover can be caused between the two, and it exhibits stable protection characteristics against lightning surges. Therefore, according to the present invention,
It is possible to reliably limit or cut off the follow-on current caused by a lightning flash to prevent wire breakage and insulator damage, protect electric lines, and prevent power outages by recovering insulation on its own in the event of a ground fault or short circuit. Furthermore, the present invention does not require any other attachment parts as in the past, so it has the advantage of being simple in structure, compact and lightweight, and can be easily installed on existing railway lines. Therefore, the present invention has extremely great practical value.

[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 main part. 1: Current-limiting element unit, 1a: Current-limiting element, 1
b: discharge electrode, 1c: power supply side electrode, 1d: mantle, 2: insulator, 3: metal binding wire, 3a: spiral grip, 4: insulated wire.

Claims (1)

[Scope of utility model registration request] A material with non-linear voltage-current characteristics is placed on one side of the spiral gripping portion 3a of the metal binding wire 3, which has spiral gripping portions 3a on both sides for attaching the insulated wire 4 to the head of the insulator 2. A current-limiting element unit 1 is formed by covering a current-limiting element 1a, a discharge electrode 1b, and a charging side electrode 1c with a jacket 1d made of an insulating material, and is fixed together with the charging side electrode 1c. 1. A metal binding wire with a current limiting element unit, characterized in that the wire is electrically connected to the current limiting element unit.