JPS587809Y2 - Insulated connections for rubber and plastic cables - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement in the insulated connection portion of a rubber or plastic cable when a cross-bond method is adopted for a three-phase power transmission line using a single electrocardiogram cable.

Generally, in a three-phase power transmission line using a single-core cable, a cable shielding layer is insulated at the cable connection part in order to block current due to sheath induced voltage.

(Hereinafter, this will be referred to as an insulated connection part.) In order to protect the insulation of the edge cut part (the end of the shielding layer) of the insulated connection part, conventionally, as shown in FIG. A method is adopted in which a copper tube 3 incorporating an insulating tube 2 in a part is provided on the outer periphery, and the surface flash level of the insulating tube is made lower than the insulation strength of the edge cut portion 4.

In the figure, 5 and 5' indicate a shielding layer, and 6 and 6' indicate a cable 7 that is a corrosion protection layer wrapped with tape.

However, when forming insulated connections using such steel pipes, a work step for injecting waterproofing compound 8 between the shielding layer 5,5' and the copper pipe 3 is essential. , it is also economically disadvantageous.

Therefore, in recent years, there has been a growing trend to reconsider the use of steel pipes and consider that they are not necessarily necessary.

In other words, instead of wrapping the anti-corrosion layer with conventional tape, studies are underway to create a structure in which a heat-shrinkable tube made of the same material as the cable anti-corrosion layer, such as vinyl chloride, is tightly attached to the cable shielding layer. There is.

However, in the latter case, an insulating tube cannot be attached, so
Regarding the function of the insulating cylinder, that is, the protection of the edge cut portion, it is necessary to consider the use of the insulation tube along the surface between the edge cut portions.

In this case, 1. Creeping flash may occur frequently and may cause insulation deterioration, making insulation monitoring management complicated, and recovery in the event of insulation deterioration is not easy.

The present invention has been developed with this in mind, and aims to provide an insulated connection part for rubber or plastic insulated cables that allows easy monitoring of insulation by providing an insulation protector on the outside of the cable connection part. It is something.

Hereinafter, the present invention will be explained based on the drawings of one embodiment.

As shown in FIG. 2, the insulated connection part 9 of the rubber/plastic insulated cable according to the present invention includes an omitted cable conductor connection part (not shown) and a reinforcing insulator (not shown) provided on the outer periphery of the cable conductor connection part (not shown).
and shielding layers 10, 10' provided insulated on the outside thereof,
It mainly consists of a heat-shrinkable tube 12 provided across two pairs of cable sheaths 11 and 11', and an insulating protector 13 provided outside the insulating connection part.

The cable conductor connection section is composed of a pair of cable conductors and a sleeve in which the ends of the conductors are compressed and connected.

The insulating reinforcing body is formed by heat-molding polyethylene tape wound overlappingly, or by molding a bottom of a compound by an injection method or the like.

A pair of shielding layers 10.degree., 10' are connected at one end to the respective cable shielding layer, and the other ends are electrically insulated and separated by an insulator as shown in the figure.

The heat-shrinkable tube 12 can be used as a substitute for the conventional buttoned anti-corrosion layer, and after the pair of anti-corrosion layers 10° and 10' have been provided, it is inserted into one of the cables in advance and buttoned, and then placed over the connection part. The pair of shielding layers 10, 10' and the cable sheaths 11, 11' are pulled back and heated.
closely followed.

As shown in FIG.
and 5 a pair of metal fittings 15°15' that hold both ends of this.
A pair of metal springs 16.1 connected to the fittings
6', a pair of lead wires 17 and 17' drawn out from the respective springs, and an outer sheath 18 that covers them all.

Each lead wire is connected to a ground wire pull-out terminal 19.
, 19' to maintain discharge strength.

The insulating rod 14 may be an insulating cylinder or a metal gap as long as it can have a predetermined flash fault resistance.

The outer cover 18 for preventing water intrusion and staining may be made of any material as long as it can maintain insulation, but it is preferably formed of a transparent material in order to easily inspect the deterioration of the surface of the insulating rod.

As mentioned above, in the button of the present invention, the protector is provided on the outside of the insulated connection part, and the inside of the protector is configured to be monitored from the outside, so compared to the conventional insulated connection part. It has the advantages described below.

(1) Since there is no need to use a waterproofing compound, the work of forming the connection portion is simple.

(2) Since a shrink tube is used as the anti-corrosion layer, the anti-corrosion layer can be easily and quickly formed.

(3) It is easy to attach the protector used as the insulating part for protecting the edge cutting part, and the insulation can be monitored from the outside.

[Brief explanation of the drawing]

Fig. 1 is a partially omitted vertical sectional view of the insulated connection portion of a conventional rubber/plastic cable, Fig. 2 is a partially omitted longitudinal sectional view of the rubber/plastic cable according to the present invention, and Fig. 3
The figure shows a longitudinal sectional view of the protector used with the button of the present invention. 9...Insulated connection part, 10.10'...
Shrink layer, 11, 11'... Cable sheath, 12... Heat shrinkable tube, 13...
・Protective body, 14... Insulation rod, 16, 16'...
... Conductive spiral, 18 ... Outer covering.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A pair of cable shielding layers are insulated and provided on the outer periphery of an insulating reinforcing layer covering the cable conductor connection portion, and a heat-shrinkable tube is placed on top of the insulation reinforcing layer to extend between the pair of cable sheaths. An insulated connection of rubber or plastic insulated cables, characterized in that an insulating protector is provided on the outside of an insulated connection part comprising: and the insulating protector is connected between the pair of cable shielding layers via a lead wire. Department. 2. The rubber or plastic according to claim 1 of the utility model registration claim, in which the insulating protector is composed of an insulator, a pair of conductive springs supporting both ends of the insulator, and an insulating tube that covers the entirety of these springs. Insulated connections of insulated cables.