JPH028429B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a rubber-plastic power cable connection constructed using heat shrink tubing.

Background of the Invention Conventionally, connections using heat-shrinkable tubes have been put into practical use mainly in power distribution cables of 22 kV or less. In this case, it is also known that a heat-shrinkable tube made of a high dielectric constant layer is provided on the innermost side to reduce the electric field and thereby reduce the size of the connecting portion.

However, in the conventional case, only a reinforcing insulating layer was constructed using a heat-shrinkable tube, and it was necessary to apply a metal insulation layer on top of that, and then provide a corrosion-proofing layer and a protective tube on top of that.

Structure and Object of the Invention The present invention simplifies work by constructing a connection part using a heat-shrinkable tube in which a high dielectric constant layer, an insulating layer, an external semiconducting layer, and an anticorrosive layer are integrally formed. This is intended to shorten assembly time.

1st Embodiment In "Fig. 1", 10 is the entire cable,
12 is a cable conductor, 14 is a cable insulator, 1
6 is an outer semiconducting layer, 18 is a cable metal insulation layer, and 20 is a cable sheath.

Reference numeral 30 denotes a connection section, which includes a high dielectric constant layer 32 and an insulating layer 3.
4. The outer semiconducting layer 36 and the anticorrosion layer 39 are integrated, and this is constructed by shrinking the heat shrink tube 30a shown in FIG. 2.

High dielectric constant layer 32a of heat shrink tube 30a
For example, it is made by mixing powders such as carbon and titanium oxide into a base material such as cross-linked polyethylene or EP rubber.

Further, the insulating layer 34a is made of crosslinked polyethylene or EP rubber.

Further, the outer semiconductive layer 36a is made of crosslinked polyethylene.
It is made by mixing carbon powder etc. into the base of EP rubber.

The anticorrosive layer 38a is made of polyethylene, chloroprene, or the like.

The above four layers are integrally formed. To make it, for example, the four layers described above are simultaneously extruded using a multilayer extruder to impart heat shrinkability.

Note that before shrinking the heat shrink tube 30a,
A tape wrapping layer 40 is applied to fill in the valleys.

Further, 42 is a shield wire for electrically connecting the left and right cable metal shield layers 18. This is made of, for example, copper wire, which is wound around one cable metal insulation layer 18, spirally wound over the connection part 30, and then wrapped again around the cable metal insulation layer 18 on the opposite side. It is.

In addition, in "Figure 1", Shiyahei wire 4
Although only one 2 is shown, in reality there are many.

Further, numeral 44 denotes a tape-wrapped layer, which is provided for moisture-proofing the end portion of the connecting portion 30.

Second Embodiment In the above case, it was necessary to shrink the heat-shrinkable tube 30a and install the plastic wire 42, but in this embodiment, this step is not necessary.

That is, in this case, a heat shrink tube 30b as shown in "Fig. 3" is used.

This heat-shrinkable tube 30b also includes a high dielectric constant layer 32b, an insulating layer 34b, an outer semiconducting layer 36b, and an anticorrosive layer 38b in the same manner as described above, but also includes a flexible wire 37. .

This flexible wire 37 is made of, for example, a copper wire, and is either embedded in the outer semiconducting layer 36b or placed between the outer semiconducting layer 36b and the anticorrosive layer 38b. In this case, the tube is waveformed as shown in FIG. 3; by doing so, it is possible to follow changes in the length direction of the shrinkable tube during heating contraction, and the flexibility against bending is improved.

"FIG. 4" shows the connection part 30 made by shrinking the heat shrink tube 30b.

In this case, a copper wire 46 is used to connect the flexible wire 37 embedded in the heat-shrinkable tube 30b to the cable metal flexible layer 18 of the cable 10.

Effects of the Invention Since the connection part is constructed using a heat-shrinkable tube that is integrated with the anti-corrosion layer in advance, the connection work is simplified and the assembly time is shortened.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the first embodiment of the present invention, and FIG.
The figure is an explanatory view of the heat shrink tube 30a, FIG. 3 is an explanatory view of the heat shrink tube 30b used in the second invention, and FIG. 4 is a sectional view of the second embodiment. 10: Cable, 18: Cable metal insulation layer, 20: Cable sheath, 30: Connection part, 30
a, 30b: heat shrink tube, 32, 32a, 3
2b: High dielectric constant layer, 34, 34a, 34b: Insulating layer, 36, 36a, 36b: External semiconducting layer, 3
8, 38a, 38b: anti-corrosion layer, 37: hard wire, 42: hard wire.

Claims (1)

[Scope of Claims] 1. Consisting of a heat-shrinkable tube in which a high dielectric constant layer, an insulating layer, an outer semiconducting layer, and an anticorrosion layer are integrally formed in order from the inside to the outside. A rubber/plastic cable connection part characterized by: 2. The connection portion of the rubber/plastic cable according to claim 1, wherein the external semiconductive layer has a flexible wire embedded therein or provided in contact with the external surface. .