JPS5825708Y2 - power cable junction box - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power cable connection box, and more particularly to improvements in the connecting portion between an aluminum connection conductor connected to an aluminum core conductor of a power cable and an aluminum internal electrode of an insulator.

A power cable junction box consists of a connecting conductor that is connected to the core conductor of the power cable, an internal electrode that is electrically connected to the connecting conductor and exposed on the inner surface, and an outer surface (the exposed external electrode is buried and connected to the core conductor). The connecting conductor is made up of an insulator that surrounds the connecting conductor, and a stress conductor that is inserted between the insulating layer of the power cable and the insulator. The connecting portion includes a mating stopper and a threaded portion into which a fastening fitting is screwed so as to tighten the annular protrusion toward the stopper.

If the core conductor of the electric cable is made of aluminum, the connecting conductor must also be made of aluminum, and therefore the internal electrode of the insulator must also be made of aluminum.

However, the electrical contact between the aluminum connecting conductor and the aluminum internal electrode is incomplete due to the insulating oxide film formed on the surface, and there is a risk that a discharge phenomenon may occur between them and cause electrical breakdown. .

An object of the present invention is to provide a power cable connection box that can make complete electrical contact between an aluminum connection conductor and an aluminum internal electrode.

The embodiments of the present invention will be described in detail with reference to the drawings.
The figure shows a power cable connection box 10 according to the present invention, which connects aluminum core conductors 1a, 1'a of power cables 1, 1' to each other and is connected to these core conductors. aluminum connecting conductor 12 and core conductor 1a.

An insulator 14 made of a cylindrical epoxy resin molded body surrounding the connecting conductor 1'a and the connecting conductor 12;
The stress cones 16, 16' are inserted between the insulating layers 1a, i'b and the insulator 14.

The insulator 14 has an annular inner electrode 18 made of aluminum exposed on the inner surface and two annular outer electrodes 2 exposed on both ends of the outer surface.
0.20' is embedded.

As shown in FIGS. 2 and 3, the connecting conductor 12 has a sleeve portion 22 having an H-shaped cross section into which the aluminum core conductors 1a and 1'a are fitted, and an annular protrusion 18a of the internal electrode 18 that abuts against each other. The connecting portion 28 includes a stopper 24 and a threaded portion 26 into which is screwed a tightening fitting 30 that tightens the annular protrusion 18a toward the stopper 24 so as to pinch the annular protrusion 18a toward the stopper 24.

The core conductors 1aj1'a of the power cables 1, 1' are fitted into the sleeve portion 22 of the connection conductor 12, and the sleeve portion 22
are connected to each other by pressure compression and the connecting conductor 1
Connected to 2.

As shown in FIGS. 2 and 3, the internal electrode 18 is assembled by screwing the fastening fitting 30 onto the threaded portion 26 of the connecting conductor 12, so that the annular protrusion 18a is connected to the stopper 24 and the fastening fitting 30.
and is electrically connected to the connecting conductor 12.

In the power cable connection box 10 of the present invention, FIGS.
As shown in the figure, a conductive toothed washer 32 is interposed between the annular protrusion 18a of the internal electrode 18 and the stopper 24.

The toothed washer 32 has teeth 32a on a surface facing the annular protrusion 18a and the stopper 24. It is injected into the protrusion 18a and the stopper 24.

Therefore, the insulating aluminum oxide film on the opposing surfaces of the annular protrusion 18a and the stopper 24 is broken, and they are electrically connected via the conductive toothed washer 32.

The insulator 14 is fitted in advance to one of the power cables, for example, the power cable 1, and the connecting conductor 12 is fitted to the core conductor 1.
a, 1'a, the core conductors 1a, 1'a and the connecting conductor 12 are pulled together to surround the annular protrusion 18a of the internal electrode 18 through the toothed washer 32. The fastening fitting 30 is screwed into the threaded portion 26 with a suitable jig and tightened within the inner space of the internal electrode 18 so as to abut against the stopper 24 of the connecting conductor 12 .

In this way, the insulator 14 is fixed and the internal electrode 18 is connected to the core conductor 1a.

1'a.

The stress cone is also coated with the insulation layer 1 of the electrical cables 1 and 1' in advance.
b, 1'b, and after connecting the insulator 14, it is pulled to both sides of the insulator and the stress cone holding fitting 34.
The external electrode 20
．． 20', and also connect the electric cables 1 and 1 in the same way in advance.
The cable protection fittings 3B, 38' that fit into the adapters 36, 36' are installed between the adapters 36, 36' and the power cables 1, 1'.

Stress cones 16, 16' are adapters 36, 36
The insulator 14 and the cable insulation layers 1b, 1'b are brought into contact with a predetermined surface pressure by the springs 40, 40' provided between the stress cone pressers 34, 34'.

Cable protection fittings 3B and 38' are external electrodes 20 and 20'
and the outer cover of the power cable 1, 1' are electrically connected.

Note that 42 and 42' are the waterproof tapes wound between the adapters 36 and 36' and the cable protection fittings 38 and 38', and 44 and 44' are the cable protection fittings 38 and 38.
This is a waterproof tape wrapped between the electric cable 1, 1' and the electric cable 1, 1'.

A storage case (not shown) is fitted to one of the power cables 1, and after the above operation, the power cables 1, 1' are pulled together.
will be added to.

In addition, the aluminum core a and the conductor l of the power cables 1 and 1'
a and l'a may be connected to each other by welding, and in this case, the connecting conductor 12 is made by welding the sleeve portion 22 together with the welded portion of the core conductor instead of having the sleeve portion 22 in the form of a bridge or a sleeve having a cutout window. Alternatively, the sleeve portion 22 may be formed into a hollow sleeve shape over its entire length and may be compressively connected to the core conductors 1a and 1'a.

According to the present invention, as described above, since a conductive toothed washer is interposed between the annular protrusion of the aluminum internal electrode of the insulator and the stopper of the aluminum connecting conductor, the electrical connection between the internal electrode and the connecting conductor is Contact will not be incomplete,
Therefore, the power cable connection box will not be destroyed by discharge.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing a half of the power cable connection box according to the present invention, Fig. 2 is an enlarged sectional view of the state in which the internal electrode is connected to the connecting conductor, and Fig. 3 is a diagram showing the connection between the internal electrode and the connecting conductor. FIG. 3 is a further enlarged sectional view of the connecting portion. 1.1'...Electric cable, 1a, 1'a...
...Aluminum core wire conductor, 1 b, l'b・
... Insulating layer, 10 ... Power cable connection box, 12 ... Aluminum connection conductor, 14 ...
...Insulator, 16, 16'...Stress cone, 18...Aluminum internal electrode, 20
, 20'...External electrode, 24...Stopper 26...Threaded part, 28...Connection part, 30...Tightening fitting , 32... Conductive toothed washer.

Claims (1)

[Scope of utility model registration request] An aluminum connection conductor connected to the aluminum core conductors of the two power cables, an aluminum inner electrode electrically connected to the connection conductor and exposed on the inner surface, and an aluminum outer electrode exposed on the outer surface are buried and connected to the core wire conductor. an insulator surrounding the connecting conductor, and a stress cone pushed between the insulating layer of the power cable and the insulator,
The connecting conductor includes a connecting portion having a stopper against which the annular protrusion of the internal electrode of the insulator abuts, and a threaded portion into which a fastening fitting is screwed so as to tighten the annular protrusion toward the stopper. An electric cable full connection box, wherein a conductive toothed washer having teeth on a surface facing the annular protrusion and the stopper is interposed between the annular protrusion of the internal electrode and the stopper.