JPS6021851Y2 - power cable - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of an electric cable made by twisting a sector-shaped insulated wire core and a round-shaped insulated wire core.

Conventionally, as shown in FIG. 1, this type of cable cable has conventionally consisted of three insulated wire cores 1 each having a sector-shaped conductor 2 coated with a sector-shaped insulating layer 3 made of polyethylene or the like on the outside, and a round conductor 5 coated with a sector-shaped insulating layer 3 made of polyethylene or the like on the outside. An insulated wire core 4 coated with a round insulating layer 6 is twisted in a circle together with an inclusion 7 made of jute or the like, a holding tape 8 such as a polyester tape is wrapped around the outside, and a sheath layer 9 of vinyl resin or polyethylene is twisted.
This is coated with a wire mirror device 0 and an anticorrosion layer 11 made of vinyl resin to obtain an anticorrosive layer capeple.

In such cables, the sector-shaped insulated wire core is usually used for the R, S, and T phases of the three phases, and the round-shaped insulated wire core is used as the neutral wire or ground wire. .

However, when twisting the sector-shaped insulated wire core and the round-shaped insulated wire core, there is a risk that inclusions may sink into the center.

Therefore, the shape after twisting becomes distorted, and it is extremely difficult to finish it into a circular shape.Therefore, there is a risk that the shape may be distorted or the outer diameter of the twisted product may be larger than the predetermined dimension calculated geometrically. was there.

This tendency became more pronounced as the diameter of the cable became larger.

In the present invention, as a result of intensive research to improve these drawbacks, it was discovered that sector-shaped insulated wire cores and round-shaped insulated wire cores can be twisted together in a circular shape.

That is, the present invention is a power cable made by twisting a three-core sector-shaped insulated wire core and a one-core round insulated wire core, in which inclusions are extruded to form a sector shape on the outside of the round insulated wire core. It is made by covering and twisting four sector-shaped insulated wire cores into a circular shape.

An example of the present invention will be explained in detail based on the drawings.

As shown in FIG. 2, a sector-shaped insulated wire core 1 and a round insulated wire core 6 are formed in the same manner as described above, and an intervening layer 12, e.g. It is formed by extrusion coating with rubber inclusions such as ethylene-propylene type, natural rubber type, and chloroprene rubber type, or plastic inclusions such as polyvinyl chloride type and polyethylene type.

Note that this intervening layer may contain an anti-aging agent, a plasticizer, etc.

By twisting together the four-core sector-shaped insulated wire cores, the outer shape easily becomes circular.
A push tape 8 and a sheath layer 9 are provided on the outside in the same manner as described above, and if necessary, a wire mirror device 0 and a corrosion protection layer 11 are further applied on the outside to easily obtain a corrosion protection layer.

Note that in order to make the intervening layer 12 easier to peel than the round insulated wire core 6, a peeling substance may be mixed into the intervening layer 12, or a peeling material such as silicon may be applied between the two. good.

According to the present invention, it is possible to transform a round insulated wire core into a sector-shaped insulated wire core without requiring any inclusions as in the prior art, so that it has the following effects.

(1) Since inclusions do not sink into the center, the shape after twisting can be maintained as round, so the outer diameter after twisting can be adjusted to the specified size without deformation. I can finish it.

Therefore, the quality of the cable is stable and the yield is high, so costs can be reduced significantly.

(2) Since the outer diameter of the cable is always constant, the drum can also be small, and transportation costs can be reduced.

[Brief explanation of drawings]

Figure 1 is a sectional view showing an example of a conventional power cable;
The figure is a cross-sectional view showing an example of the capple of the present invention. 1.4... Insulated wire core, 2... Sector-shaped conductor, 3... Sector-shaped insulating layer, 5...
...Round conductor, 6...Round insulating layer 7...
...Inclusions, ends...Tape, 9...Sheath layer, 10...Iron wire armor, 11...Corrosion protection layer, 12...・Intervening layer.

Claims (1)

[Scope of utility model registration request] In a power cable formed by twisting a three-core sector-shaped insulated wire core and a one-core round insulated wire core, an inclusion is extruded and coated on the outside of the round insulated wire core so as to form a sector shape,
An electric cable made by twisting four sector-shaped insulated wire cores into a circular shape.