JP3193823B2 - Mounting structure of insulated wire to insulator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for mounting a covered electric wire installed on an electric wire path to an insulator.

[0002]

2. Description of the Related Art Conventionally, insulated wires covered with insulation are attached to support insulators by means of bind wires and installed in distribution lines. This bind wire binds the covered electric wire to the supporting insulator by wrapping a conductive bare wire around the neck of the supporting insulator erected on the pole of the utility pole and spirally winding both sides of the covered electric wire around the covered electric wire. .

Further, as disclosed in Japanese Utility Model Publication No. 55-21450, there is known a so-called conductive insulator made by applying a conductive lubricant to the surface of the insulator. This conductive yu insulator is designed to prevent leakage current by drying the insulator surface promptly due to Joule heat generated by causing the leakage current from the coated wire to flow to the surface when it is soiled or wet. Thus, the insulating strength of the supporting insulator is increased. Also in this prior art, it is attached to a covered electric wire by a bind wire made of a conductive bare wire.

[0004]

The contact area between the supporting insulator and the coated electric wire has a high potential gradient because the contact area between the supporting insulator and the coated electric wire is small as shown by point P in FIG. Leakage current is concentrated at this point P, which tends to cause a partial discharge, and has a problem that the withstand voltage for fouling is reduced. In particular, even when a conductive insulator was used as the support insulator, it was difficult to prevent partial discharge.

[0005] Further, since the bind wire extends from the circumferential surface of the support insulator to the covered wire, rainwater or dust easily accumulates between the bind wire and the covered wire. Intensively flows to generate spark discharge, causing insulation deterioration due to burning and corrosion of the wire conductor due to water intrusion.

Accordingly, an object of the present invention is to provide a structure for attaching an insulated wire to an insulator, which protects the insulated coating of the insulated wire and enhances the insulation strength of the wire path.

[0007]

According to the first aspect of the present invention, there is provided a structure for attaching a covered electric wire to an insulator, wherein the covered electric wire is insulated by a conductive bind wire hooked on a neck of a supporting insulator. The wire is electrically connected to the insulated wire and provided at the same potential as the insulated wire, and is in direct contact with a contact portion that contacts the supporting insulator. In the invention according to claim 2, the end of the bind wire is electrically connected to the covered electric wire. According to a third aspect of the present invention, a support insulator having a surface coated with a conductive lubricant holds an electric wire insulated by a bind wire.

[0008]

According to the first aspect of the present invention, a conductive bind wire is hooked on the neck of the support insulator, and the insulated wire is gripped by the support insulator. Therefore, a contact portion is formed in which the binding wire directly contacts the neck in a linear manner. In addition, since the bind wire is electrically connected to the insulated wire and provided at the same potential as the insulated wire, the potential gradient is reduced at the linear contact portion, and the leakage current can flow stably.
Local concentration of leakage current is reduced. As a result, the withstand voltage of the insulator surface at the time of fouling and wetting is improved. In addition, when the withstand voltage at the time of fouling is reduced, there is no partial discharge due to leakage current at the contact portion between the insulated wire and the bind wire at the same potential, thereby preventing the insulation coating from being deteriorated or damaged. You.

According to the second aspect of the present invention, since the end of the bind wire that tends to cause electric field concentration is electrically connected to the covered electric wire,
Electric field concentration is reduced. Further, the invention of claim 3 is applied to a support insulator having a surface provided with a conductive agent,
When wet, leakage current flows from the contact of the bind wire,
The insulator surface dries early due to the Joule heat generated at that time.

[0010]

According to the first aspect of the present invention, since the bind wire is electrically connected to the insulated wire and provided at the same potential as the insulated wire, and is directly in contact with the support insulator,
Since the leakage current flows stably on the insulator surface and the partial discharge is prevented, the effect of protecting the covered electric wire is exhibited. According to the second aspect of the present invention, the electric field concentration is reduced by electrically connecting the end of the bind wire, which tends to cause the electric field concentration, to the covered electric wire. According to the third aspect of the present invention, since the electric wire covered with the insulating wire by the binding wire is gripped by the supporting insulator whose surface is coated with a conductive lubricant, the surface of the insulator is quickly dried and has a high withstand voltage. A structure for attaching the covered electric wire to the insulator can be provided.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 shows an embodiment of the present invention. A substantially cylindrical support insulator 1 is provided upright on an arm of a utility pole (not shown). On top of the support insulator 1, a cap portion 1a and a head portion 1b
A neck portion 1c having a reduced diameter is formed therebetween, and a covered electric wire 2 is attached to a side surface of the neck portion 1c by a bind wire 3. The covered electric wire 2 is a distribution line, and an electric wire conductor 2a formed of a conductive twisted wire is covered with an insulating coating 2b. The bind wire 3 is formed by converting a single bind lead wire 3a to an insulating coating 3b.
A flexible wire rod insulated and covered with a wire, and a neck portion 1c is hooked approximately at the center of the bind wire 3, and both sides of the wire wire are spirally wound around the coated electric wire 2 several times to provide a wound portion 3c. ,
The covered electric wire 2 is attached to the support insulator 1. As shown in FIG. 3, an attachment screw portion 3d formed by cutting the bind conductor 3a is provided at the tip of one of the winding portions 3c of the bind wire 3.

As shown in FIG. 2, the binding wire 3 is in linear contact over approximately half the circumference of the neck 1c. At the contacting portion, the insulating coating 3b is removed and the binding wire 3a is removed. The exposed contact portion 3e is in direct contact with the support insulator 1 in a bare wire state.

The binding screw 3d allows the binding wire 3
Is attached to the covered electric wire 2 by an electric wire clip 4. As shown in FIGS. 3 and 4, the electric wire clip 4 has a lower holding piece 11 and an upper holding piece at both ends of a spring piece 10 urged so that a strip-shaped thin plate made of a conductive material is curved in an arc shape. The piece 12 is fixed and is sandwiched between the covered wire 2 from above and below by the sandwiching pieces 11 and 12.

A block-shaped lower contact 13 made of a conductive material is provided in the lower holding piece 11, and a screw hole 13 for screwing a conductive screw 14 is formed on the lower surface of the lower contact 13.
a is formed. A block-shaped upper contact 15 is provided in the upper holding piece 12, and is screwed to a mounting screw portion 3d formed on a side surface of the upper contact 15.
Is connected to the upper contact 15. For this reason, in a state where the covered electric wire 2 is attached by the electric wire clip 4, the tip of the conductive screw 14 screwed to the lower contact 13 breaks through the insulating coating 2 b of the covered electric wire 2,
Conduction with the electric wire conductor 2a is performed, and the bind conductor 3a of the bind wire 3 is electrically connected from the lower contact 13. Therefore, at the time of energization, the bind wire 3 is set to the same potential as the electric wire conductor 2a.

The electric wire clip 4 is attached to the lower holding piece 1.
1. The whole of the spring piece 10 and the upper holding piece 12 is covered with an insulating film 16 made of soft plastic or rubber, so that insulation and corrosion resistance are achieved. As shown in FIG. 4, the holding surfaces 11 a and 12 a of the upper and lower holding pieces 11 and 12 are formed into circular arc surfaces having a cross-sectional shape smaller than the curvature of the cross section of the covered electric wire 2. The insulating coating 2b is bitten in two places on both sides with respect to the outer peripheral surface, and is attached without turning around the electric wire.

The operation of this embodiment mounted as described above will be described. After the binding wire 3 is hooked on the side surface of the neck portion 1c of the support insulator 1, both sides are wound around the outer periphery of the covered electric wire 2 several times. By providing the winding part 3 c, the covered wire 2 is supported on the side surface of the neck part 1 c by the bind wire 3. Next, the wire clip 4 is attached. This mounting is performed by the two holding pieces 1 against the urging force of the spring piece 10.
The outer surface of the insulated wire 2 is clamped after the space between the wires 1 and 12 is expanded. When the conductive screw 14 is screwed into the screw hole 13a, the conductive screw 14 is electrically connected to the electric wire conductor 2a and attached. As described above, the bind wire 3 can be easily conducted to the insulated wire 2 simply by screwing the conductive screw 14 while holding the wire clip 4 between the insulated wire 2.

Thus, the one end of the bind conductor 3a is electrically connected to the electric wire conductor 2a via the electric wire clip 4 and the electric power is applied to the bind conductor 3a, so that the electric potential is the same as that of the electric wire conductor 2a. In other words, the contact portion 3e that is in linear contact with the cervical portion 1c over approximately half the circumference has the same potential as the potential of the covered electric wire 2. Therefore, the support insulator 1
If the surface of the support insulator 1 is wet, particularly when it is soiled, the leakage current is diverted over a wide area of the surface of the support insulator 1 and local current concentration is prevented. On the other hand, the covered electric wire 2 and the supporting insulator 1
At the contact point P, the insulated wire 2 is in contact with the supporting insulator 1 via the insulating coating 2b, but the leakage current generated from the contact point P is reduced, and the supporting insulator 1
Through the ground. That is, the leakage current does not flow locally from the contact point P,
Since the current density is reduced by shunting, the occurrence of partial discharge is prevented, and the withstand voltage against contamination is increased.

Even if dust or rainwater accumulates between the insulated wire 2 and the bind wire 3, the contact portion 3 e of the same potential directly in contact with the supporting insulator 1, as described above. , Leakage current flows from this portion and current concentration does not occur between this portion and the insulated wire 2, so that spark discharge that destroys the insulating coating 2b is prevented.

Further, in this embodiment, since the distal end of the bind wire 3 where the electric field concentration tends to occur is provided with the mounting screw 3d and is screwed to the wire clip 4, the electric field concentration at the distal end of the bind wire 3 is reduced. Be relaxed.

Further, when the support insulator 1 is made of a conductive insulator having a conductive agent applied to its surface, the leakage current at the time of contamination becomes large, and the insulator surface becomes prompt due to Joule heat accompanying the contamination. The high withstand voltage can be recovered and maintained again.

In this embodiment, an example is shown in which the contact portion 3e is a bare wire exposing the bind conductor 3a.
It is not necessary to use a bare wire, and the insulating wire 2b may be the same insulating film as the insulating film 2b of the covered electric wire 2, or may be a film thinner than the insulating film 2b. In this embodiment, an electric wire clip 4 is attached to the bind wire 3 and the electric wire clip 4
However, it is not always necessary to use the wire clip 4.

[Brief description of the drawings]

FIG. 1 is a partially cutaway side view.

FIG. 2 is a partial cross-sectional view.

FIG. 3 is a partially cutaway enlarged side view of a part.

FIG. 4 is a sectional view taken along line AA.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Support insulator 1c ... Neck 2 ... Insulated wire 2b ... Insulating coating 3 ... Bind wire 3b ... Insulating coating 3e ... Contact part 4 ... Wire clip

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-56-49617 (JP, A) JP-A-52-76998 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02G 7/00 H01B 17/20

Claims (3)

(57) [Claims] 1. A structure for attaching a covered electric wire to an insulator for gripping a covered electric wire insulated by a conductive bind wire hooked on a neck portion of a supporting insulator, wherein the bind wire is electrically connected to the covered electric wire. Provided at the same potential as the insulated wire,
Further, a mounting structure of the coated electric wire to the insulator, wherein the contact portion is in direct contact with the contact portion which contacts the supporting insulator. 2. The structure according to claim 1, wherein the end of the binding wire is electrically connected to the covered wire. 3. The mounting structure according to claim 1, wherein the electric wire covered with the insulating wire by the binding wire is gripped on a supporting insulator whose surface is coated with a conductive lubricant.