JP2552203Y2 - Power cable connection - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molded connecting portion of a plastic power cable, and more particularly to a connecting portion having a structure in which a high dielectric constant layer is arranged inside an outer conductor for improving electric insulation performance. Things.

[0002]

2. Description of the Related Art In FIG.
2 is a cable insulator and 14 is a cable outer shielding layer. Reference numeral 16 denotes a reinforcing insulator manufactured by a molding method, and reference numeral 18 denotes an external shielding layer of a connection portion. A high dielectric constant layer 20 is provided inside the connection portion external shielding layer 18 to thereby alleviate an electric field and improve electrical insulation performance. The tip 140 of the cable outer shielding layer 14 enters inside the end of the high dielectric constant layer 20. By doing so, the electric field at the end of the cable outer shielding layer 14 (the joint with the connection part outer shielding layer 18), which tends to be a weak point, is eased, and the construction is also facilitated.

[0003]

[Problem to be solved by the invention] Cable outer shielding layer 1
The tip 140 of 4 has a tapered shape (because the tip is cut away). In general, electric flux has a property of gathering toward a dielectric having a high dielectric constant. Therefore, as shown in FIG.
The equipotential line wraps around 40, and the electrical stress at the tip 140 increases. As a result, there is a problem that the dielectric breakdown easily occurs from the tip 140 and the high dielectric constant layer is provided, so that the electric performance is rather deteriorated.

[0004]

Means for Solving the Problems As shown in FIG.
A reinforcing layer 22 made of a semiconductive layer having a rounded zero is placed over the tip of the cable outer shielding layer 14 so that the rounded tip 220 enters inside the end of the high dielectric constant layer 20.

The reinforcing layer 22 is suitably formed using a semiconductive heat-shrinkable tube (uncrosslinked with a crosslinking agent). That is, a heat-shrinkable tube having a rounded end is made in advance, and the heat-shrinkable tube is covered from the front end portion of the cable outer shielding layer 14 to the cable insulator 12 and is thermally contracted and adhered.

[0006] The high dielectric layer 20 is formed such that its end is the reinforcing layer 2.
The second tip 220 is formed so as to cover the tip 220. High dielectric constant layer 20
A connection portion external shielding layer 18 is provided on the upper surface of the substrate, and the end portion thereof and the reinforcing layer 22 are electrically connected. Then, the reinforcing layer 22,
The high dielectric constant layer 20 and the connection portion external shielding layer 18 are collectively molded.

[0007]

[Function and effect of the invention] A reinforcing layer made of a semiconductive layer having a rounded tip is covered on the tip of the cable outer shielding layer so that the rounded tip enters the inside of the end of the high dielectric constant layer. Therefore, as shown in FIG. 2, the wraparound of the equipotential line at the tip 220 of the reinforcing layer 22 is suppressed. Therefore, the high dielectric constant layer 20 is applied to the mold connection part for the purpose of reducing the electric field, and the cable outer shielding layer 14 is provided inside the high dielectric constant layer 20.
Of the cable outer shielding layer 14 (seam with the connecting part outer shielding layer 18) which is easily cut by inserting the tip 140 of the cable outer shield layer 14 which is likely to be a weak point. The problem that the electric field is concentrated on the tip of the cable outer shielding layer is eliminated. As a result, it is possible to improve the electrical characteristics of the power cable mold connection or reduce the insulation thickness.

[Brief description of the drawings]

FIG. 1 is an explanatory view of an embodiment of the present invention.

FIG. 2 is an electric field analysis diagram near an end of a high dielectric constant layer in the embodiment of the present invention.

FIG. 3 is an explanatory diagram of a conventional technique.

FIG. 4 is an electric field analysis diagram near the end of a high dielectric constant layer according to a conventional technique.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 cable conductor 12 cable insulator 14 cable outer shielding layer 140 tip of cable outer shielding layer 16 reinforcing insulator 18 outer shielding layer of connection part 20 high dielectric constant layer 22 reinforcing layer of cable outer shielding layer 220 tip of reinforcing layer

Claims (1)

(57) [Scope of request for utility model registration] 1. A power cable according to claim 1, wherein a high dielectric constant layer is provided between the reinforcing insulator and the connection portion external shielding layer, and a tip of the cable shielding layer enters inside an end of the high dielectric constant layer. In the connection portion, a reinforcing layer made of a semiconductive layer having a rounded tip is covered on the tip of the cable outer shielding layer, and the rounded tip enters the inside of the end of the high dielectric constant layer. ,
Power cable connection.