JPS6322616Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cable connection, and particularly to a cable connection that is insulated using a heat-recoverable material (tube, tape, sheet, etc.).

Conventionally, in order to obtain the insulation strength of cable connections, the required number of heat recovery tubes, such as heat shrinkable tubes, etc.
Laminated coatings of tape, etc. are used to cover the joints, but gaps and voids are formed at the laminated interface of tubes etc. due to uneven shrinkage work or malfunction of heating tools, which can lead to insulation defects. It was becoming.

In order to prevent the occurrence of such defects, an effect has been obtained by applying an insulating liquid such as silicone oil, polybutene oil, silicone grease, etc. to the interface of the tube. However, over a long period of time, these liquids may flow out of the applied area or be absorbed by the tube material and disappear, thereby losing the effect of preventing the above-mentioned defects and potentially reducing long-term insulation performance.

Therefore, an object of the present invention is to provide a cable connection section coated with a heat-recoverable material that can maintain stable insulation properties for a long period of time without the above-mentioned defects. It is in.

That is, in the present invention, each connection end of a cable to be connected is connected by stripping each step, and each layer is coated with a heat-recoverable material in a layered manner. This is a cable connection part characterized by being impregnated with.

Heat-recoverable materials used in this invention include heat-shrinkable rubbers (e.g., EP (ethylene propylene) rubber, silicone rubber, etc.) and plastics (e.g., XLPE (crosslinked polyethylene), PVC (polyvinyl chloride), etc.). ), these are tubes,
Used in the form of tapes, sheets, etc. As the insulating liquid used in the present invention, silicone oil, polybutene oil, castor oil, grease, plasticizer for polyvinyl chloride, etc. are used.

For heat recovery, for example, to impregnate a heat-shrinkable material with an insulating liquid, the heat-shrinkable material and the insulating liquid are sealed in a high-pressure container, heated and pressurized as necessary, and the liquid is impregnated to a supersaturated state. It is preferable to let

Hereinafter, the present invention will be described by taking a heat-shrinkable tube as an example with reference to the accompanying drawings.

FIG. 1 is a partial cross-sectional view (upper half) showing one embodiment of the cable connection section according to the present invention.

First, the ends of the cables to be connected are stripped in steps in the order of conductor 1, insulator 2, external semiconducting layer 3, and shielding layer 4, and the conductors 1 of each cable are connected to each other through conductor connection tube 5.
(partially shown as a side view).
Next, the shielding tube body 6 inserted into the cable in advance is provided so as to communicate with the outer periphery of the conductor connecting tube 5 and the outer periphery of the tip of the insulator 2. next,
An insulating liquid such as silicone oil or grease is applied to the outer periphery of the external semiconductive layer 3 and the insulator 2, which are the stripped portions of the cable. As for the liquid, it is preferable to use one with as high a viscosity as possible because it will not cause problems such as dripping. If necessary, the above liquid may also be applied to the outer periphery of the shielding tube body 6. Furthermore, in the present invention, as will be described later, since a coating material impregnated with such a liquid is used, the step of applying the liquid as described above can be omitted in some cases.

Next, a part of the shielding layer 4 of both cables, the outer semiconducting layer 3, the insulator 2, and the shielding tube body 6
A heat-shrinkable material with a high dielectric constant is provided on the outer periphery of the tube body 7 for electric field relaxation. Here, tube type 7
is impregnated in advance with an insulating liquid, preferably the same type of liquid as that applied to the insulator 2 described above, to a supersaturated state. To impregnate the tube 7 with the insulating liquid, as described above, the tube and the liquid are placed in a high-pressure container, sealed, and heated and pressurized as necessary. Alternatively, a large amount of the liquid may be mixed into the tube composition and formed into a tube. Note that instead of the above-mentioned tube, a tape or sheet-like material may be wrapped around and covered. In addition, as a shielding tube, the above-mentioned rubber,
Carbon, graphite, plastic etc.
By blending SiC metal powder etc., the volume resistivity is 10 ⁶ Ω.
It is desirable to use one with a diameter of −cm or less.

An insulating tube body 8 and a shielding tube body 9 are provided in a laminated manner around the outer periphery of the electric field relaxation tube 7, and a shield wire 10 is further attached to form a connection portion according to the present invention. In this case, the insulating tube body 8 and the shielding conductive tube body 9 are made of the heat-shrinkable material as described above, and are impregnated with an insulating liquid to a supersaturated level in the same manner as the electric field relaxation tube body 7. preferable. Note that the shielding tube body 6 may be impregnated with an insulating liquid when another object in contact with the shielding tube body 6 is an insulator. Further, if one tube in contact with the laminated interfaces 12 and 13 of each tube body is impregnated with an insulating liquid, impregnation of the other tube body with liquid may be omitted.

As described above, in the cable connection part of the present invention, an insulating liquid is applied to the tube body or sheath made of a heat-shrinkable material constituting the connection part, preferably the same kind of insulating liquid as the insulating liquid applied to the cable step stripping part. Since the coating is impregnated with liquid, the liquid exists without being absorbed into these coatings, so that good insulating performance can be maintained over a long period of time. In addition, when using the present invention, even if the insulating liquid is not applied to the stepped portion of the cable, the insulating liquid supersaturated in the heat-shrinkable material oozes into defects such as voids at the laminated interface. Since this is buried, the insulation performance of the cable connection portion is improved and maintained over a long period of time.

In the above embodiment, a case where the heat-shrinkable material is used as a tube body is shown, but it can also be used as a tape shape, a sheet shape, or the like.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view (upper half) showing one embodiment of the cable connection section of the present invention. DESCRIPTION OF SYMBOLS 1... Conductor, 2... Insulator, 3... External semiconducting layer, 4... Shielding layer, 5... Conductor connection tube, 6... Shielding tube body, 7... Electric field relaxation tube body, 8... ... Insulating tube body, 9... Conductive tube body for shielding, 10... Shield wire.

Claims (1)

[Claims for Utility Model Registration] (1) At the connection part of the cable, each connection end of the cable to be connected is separated and connected, and each separated part is laminated and coated with a heat recovery material. A cable connection section characterized by a conductive material impregnated with an insulating liquid. (2) The cable connection portion according to claim (1), wherein the heat-recoverable material is heat-shrinkable rubber or plastic. (3) The cable connection portion according to claim (1) or (2), wherein the heat-recoverable material is a heat-shrinkable tube-like, tape-like, or sheet-like material.