JPS6345742Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a structure for taking out a ground wire from a cable connection part of a communication cable having a plastic jacket.

In general, communication cables, whether overhead cables or underground cables, are grounded at regular intervals primarily for security purposes.

The commonly used methods for grounding are connecting lead pipes at cable connections.
Alternatively, take out the ground wire from the metal insulation layer between the cable core and the outer sheath.
A common method is to connect this directly or indirectly to the earth.

By the way, when taking out the ground wire from the cable connection part in this way, the problem is the sealing performance (airtightness, watertightness, etc.) of the cable connection part.
For example, when connecting plastic-sheathed cables, in recent years, a so-called heat-shrinkable sleeve, etc., which has heat-sealing properties to the cable jacket, is used to cover and seal the cable connection part. The ground wire must pass through this heat-shrinkable sleeve and be taken out to the outside. In this case, since the ground wire is considerably thinner than the cable, the contact area between the ground wire and the sleeve at the penetration part is also small, which causes the problem of reduced airtightness and watertightness of the cable connection part. be.

This idea was made taking the above points into consideration.The part of the ground wire that passes through the heat-shrinkable sleeve is made of a conductive metal rod with a larger diameter than the other part, and this metal The object of the present invention is to provide a ground wire take-out structure that has a structure in which a coating layer that is heat-sealable to the heat-shrinkable sleeve is provided on the surface of the rod, thereby improving the sealing performance of the cable connection part. .

This invention will be explained below based on an embodiment shown in the drawings.

In the figure, reference numerals 1 and 2 are cables that are connected to each other, and the core connection portion 3 of the cables 1 and 2 is hermetically sealed with a heat-shrinkable sleeve 4 that is heat-sealed to the outer jacket of the cables 1 and 2. has been done. A spacer 5 is set inside the sleeve 4 and has the function of ensuring the mechanical strength of the connection portion and determining the contracted shape of the sleeve 4. In the illustrated example, the spacer 5 has a cylindrical body 5a, and the diameter becomes smaller as it goes from the body 5a toward both ends.
A support portion 5 that is pressed into contact with the outer jacket portion of the cables 1 and 2
b, 5b, and an insertion hole 5c is formed in one support portion 5b.

Reference numeral 6 denotes a conductive metal rod for taking out the ground wire from the cable connection portion covered and sealed by the heat-shrinkable sleeve 4;
A ground wire 7 made of stranded wire or the like is connected to one end, and a lead wire 8, which is also a part of the ground wire, is connected to the other end. And this lead wire 8
is guided into the spacer 5 through the insertion hole 5c and connected to a bond wire 9 that keeps the cables 1 and 2 at the same potential. The metal rod 6 has a larger diameter than the ground wire 7 and is solid, and its surface (outer circumferential surface) is made of a plastic material that can be fused to the inner layer of the heat-shrinkable sleeve 4 (for example, the inner layer of the sleeve 4 is made of plastic material). A coating layer 10 made of polyethylene (such as uncrosslinked polyethylene) is provided. Also, both end portions of this metal rod 6, that is,
The connecting portion between the metal rod 6 and the ground wire 7 and the connecting portion between the metal rod 6 and the lead wire 8 are sealed with end coverings 11 and 12, respectively, which are made of, for example, heat-shrinkable tubes and fused together. has been done.

By the way, various construction methods (procedures) can be used to implement such a ground wire extraction structure together with the cable connection work, and one example will be briefly described here.

In advance, for example, at a factory or a cable connection site, as shown in FIG. 1
Apply steps 1 and 12. Before heating and shrinking the heat-shrinkable sleeve 4 in the cable connection work, first connect the lead wire 8 to the bond wire 9 as shown in FIG. After determining the position,
The heat-shrinkable sleeve 4 may be heated and shrunk.

In this invention, since the metal rod 6 has a larger diameter than the ground wire 7, its surface area is sufficiently large, and the surface of the metal rod 6 has a coating layer 10.
is provided and is strongly heat-sealed to the inner layer of the heat-shrinkable sleeve 4, so that the sealing performance of the ground wire lead-out portion, that is, the airtightness, watertightness, etc., are significantly improved compared to the prior art. In addition, in the embodiment, the end coatings 11 and 12 also contribute to this airtightness and watertightness.

In the embodiment, an example was shown in which a solid metal rod 6 was used, but a hollow metal rod formed by sealing both ends of a conductive metal pipe, for example, may also be used.

As explained above, in this invention, the part of the ground wire that passes through the heat-shrinkable sleeve is formed with a conductive metal rod having a larger diameter than the ground wire, and the heat-shrinkable sleeve is attached to the surface of this metal rod. Since it has a structure in which a heat-sealing coating layer is provided on the cable, it has an excellent effect of significantly improving the sealing performance of the cable connection portion.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of this invention, FIG. 2 is a sectional view taken along the line - in FIG. 1, and FIG. 3 is a sectional view showing an example of the construction method. DESCRIPTION OF SYMBOLS 1, 2... Cable, 4... Heat-shrinkable sleeve, 6... Metal rod, 7... Earth wire, 8... Lead wire, 10... Covering layer.

Claims (1)

[Claims for Utility Model Registration] 1. In a ground wire take-out structure in which a ground wire is taken out from a cable connection part covered and sealed by a heat-shrinkable sleeve by passing through the heat-shrinkable sleeve, the ground wire 7 is The part that penetrates the heat-shrinkable sleeve 4 is formed of a conductive metal rod 6 having a larger diameter than the other parts, and the surface of this metal rod is coated with heat-sealing properties for the heat-shrinkable sleeve. A structure for taking out a ground wire from a plastic-sheathed cable connection part, characterized in that a layer 10 is provided. 2. A ground wire extraction structure for a plastic jacketed cable connection section according to claim 1, wherein the metal rod is a hollow metal rod with both ends sealed.