JP2000253556A - Insulating cover for cable joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform pull-back work of an insulating cover smoothly by applying a slip material to a part on the inner circumferential surface of an outer tube where an inner tube is not fixed thereby improving slippage. SOLUTION: An enlarged hole holding member is fixed to the inner circumferential surface of inner tubes 30, 31 and an outer tube 10 is enlarged at the opposite end parts thereof. A tube is inserted into the inner circumferential surface part 10A of the outer tube 10 where the inner tubes 30, 31 are not fixed and a slip material 50 is supplied to the tube and sprayed. The slip material 50 can impart slippage between the inner circumferential surface part of the outer tube and the sheath of the cable and has such properties as electric insulation and nonabsorbency of moisture. Since slippage is improved between the inner circumferential surface part of the outer tube and the sheath of the cable, pull-back work of an insulating cover can be carried out smoothly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulating cover for a cable connecting portion.

[0002]

2. Description of the Related Art Conventionally, in order to insulate and waterproof a cable connecting portion, an insulating cover is put on an outer periphery of the cable connecting portion.

[0003] As shown in FIG. 4, the insulating cover 1 has a structure in which both ends of a self-shrinkable tube 10 (hereinafter, referred to as an outer tube) are expanded by a diameter expanding support member 20. As the outer tube, a tube made of silicone rubber is used, and as the expanded diameter supporting member 20, a spirally formed plastic band having a constant width is used. The enlarged diameter support member 20 is disassembled and removed by pulling out the end of the band-shaped body.

[0004] The insulating cover 1 as described above is used to cover the cable connecting portion 80 as shown in FIG. The operation of covering the cable connection portion 80 with the insulating cover 1 is performed as follows. First, both ends of the outer tube 10 are enlarged in diameter by the enlarged diameter support member 20, and these are inserted into one of the cables before connecting the cables 90 to each other. Next, the cables 90 are connected to each other. Thereafter, the insulating cover 1 is pulled back onto the cable connection portion 80. Finally, the enlarged diameter support member 20 is disassembled and removed. Thereby, the outer tube 10
A substantially central portion in the longitudinal direction covers the cable connection portion 80, and both ends of the outer tube 10 cover a jacket (cable insulating layer or cable sheath) of the cable 90 adjacent to the cable connection portion 80.

By the way, when an insulating cover is attached to a cable connecting portion having a large diameter difference between a large-diameter cable and a small-diameter cable, if the outer tube is linear, the small-diameter side cable and the outer tube are particularly connected. There is a problem that the adhesiveness is deteriorated, and the waterproofness and the like are reduced.

Conventionally, in order to solve this problem, as shown in FIG. 6, an outer tube 10 in which the diameter of both end portions 11 is reduced is manufactured by molding, and both end portions 11 of the outer tube 10 are connected to an expanded support member. (Not shown).

According to the insulating cover 1 having the above-described structure, the adhesion between the cable on the small diameter side and the outer tube is improved and the waterproof property is improved, but the outer tube must be manufactured by forming a mold. There was a problem that it was troublesome.

Therefore, an insulating cover 1 as shown in FIG. 7 has been proposed. The insulating cover 1 has a structure including a linear outer tube 10 and inner tubes 30 and 31 arranged and fixed inside both end portions of the outer tube 1, respectively. The outer tube 10 and the inner tubes 30, 31 are both made of silicone rubber or the like.
The inner diameter of the outer tube 10 is slightly larger than the outer diameter of the conductor connection portion, so that the inner surface of the outer tube 10 is not damaged when the outer tube 10 is mounted on the connection portion. The inner diameters of the inner tubes 30 and 31 may be the same or different. If the inner diameters of the inner tubes 30 and 31 are different from each other (if different thicknesses are used), it can be easily applied to a cable connection portion in which a large-diameter cable and a small-diameter cable are connected and the diameter difference is large. There is an effect that can be. The insulating cover 1 having the above structure has an advantage that the outer tube 10 and the inner tubes 30 and 31 can be formed by cutting linear silicone rubber or the like into appropriate lengths, and thus can be easily manufactured.

In order to insulate the cable connecting portion by using the insulating cover 1 having the above-described structure, first, as shown in FIG. The diameter of both ends is increased. Next, this is inserted into one cable side before connecting the cables to each other, and after connecting the cables, the insulating cover is pulled back onto the cable connection portion. Next, the enlarged diameter support member 20 is disassembled and removed. Thereby, the outer tube 10
The center part in the longitudinal direction covers the cable connection part, and both ends of the outer tube 10 have a cable jacket (cable insulating layer or cable sheath) adjacent to the cable connection part.
Is to cover.

[0010]

As described above, the straight outer tube 10 and the inner tubes 3 arranged and fixed inside both end portions of the outer tube 10 respectively.
The insulating cover 1 having a structure including 0 and 31 can be easily manufactured, and can be easily applied to a cable connection portion having a large diameter difference between a large diameter cable and a small diameter cable. However, after connecting the cables to each other, when pulling back the insulating cover previously inserted into one of the cable sides onto the cable connecting portion, the inner peripheral surface portion of the intermediate portion of the outer tube 10, that is, the inner tube is arranged and fixed. It has been found that there is a problem that the inner peripheral surface portion (the portion denoted by reference numeral 10A in FIGS. 7 and 8) of the outer tube that is not in contact with the outer jacket of the cable makes it difficult to smoothly pull back the insulating cover.

To solve this problem, the outer tube 1
The inner diameter of 0 may be formed to be considerably larger than the outer diameter of the cable jacket. However, in this case, there is a problem that the outer diameter of the outer tube becomes large and the cost increases.

[0012]

SUMMARY OF THE INVENTION The present invention provides an insulating cover which solves the above-mentioned problems. The insulating cover comprises a linear outer tube and fixedly disposed inside both ends of the outer tube. And a sliding material is applied to an inner peripheral surface portion of the outer tube to which the inner tube is not fixed, in the insulating cover of the cable connecting portion having the inner tube.

As described above, by applying the sliding material to the inner peripheral surface of the outer tube where the inner tube is not arranged and fixed, the inner diameter of the outer tube is formed to be considerably larger than the outer diameter of the cable jacket. Even without doing so, the slipperiness between the inner peripheral surface portion of the outer tube and the jacket of the cable is improved, so that the work of pulling back the insulating cover can be performed smoothly.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view showing an embodiment of the present invention. The insulating cover 1 has a linear outer tube 10.
And inner tubes 30 and 31 respectively arranged and fixed inside both end portions of the outer tube 10. The outer tube 10 and the inner tubes 30, 31 are both made of silicone rubber or the like. For example, the outer tube 10 has a length of 100 to 500 mm and a thickness of 2 to 6 m.
m, inner tubes 30, 31 are 20-50 m long
m and a thickness of about 10 to 30 mm. The materials of the outer tube 10 and the inner tubes 30 and 31 may be different. The inner diameter of the outer tube 10 is slightly larger than the outer diameter of the conductor connection portion, so that the inner surface of the outer tube 10 is not damaged when the outer tube 10 is mounted on the connection portion.

The inner tubes 30, 31 in this embodiment have different inner diameters. That is, the inner diameter of the inner tube 30 is
1 is smaller than the inner diameter. If the inner tubes 30 and 31 have different inner diameters, that is, if the inner tubes 30 and 31 have different thicknesses, a large diameter cable connecting a large diameter cable and a small diameter cable has a large diameter. It has the advantage that it can be easily applied to parts. In addition, the inner tube 3
Needless to say, 0 and 31 may have the same inner diameter.

This insulating cover is obtained by cutting a straight tube made of silicone rubber or the like into an appropriate length to form an outer tube 1.
0, and a tube of silicone rubber or the like having an outer diameter slightly larger than the inner diameter of the outer tube 10 and a predetermined inner diameter is cut into an appropriate length to form inner tubes 30 and 31. The inner tube 30 can be easily formed by inserting the inner tubes into both ends of the outer tube 10 and arranging and fixing the inner tubes 30 and 31 inside the both ends of the outer tube. In addition,
Inner peripheral surface of outer tube 10 and inner tubes 30, 3
An adhesive or the like may be interposed between the outer peripheral surfaces of the first and the second.

The above structure is almost the same as the previously proposed insulating cover 1, but the insulating cover 1 according to the present invention.
Is characterized in that the sliding material 50 is applied to the inner peripheral surface portion 10A of the outer tube 10 where the inner tubes 30 and 31 are not fixed. As the sliding material 50, for example, silicone powder having a fine spherical shape is used. The material of the sliding material 50 is not limited to silicone powder having a fine spherical shape, but may be any material that can impart a sliding property between the inner peripheral surface portion of the outer tube and the cable jacket. A powder of a base resin can be used. However, the material of the sliding material 50 preferably has characteristics such as electrical insulation and non-hygroscopicity.

The application of the sliding material 50 to the inner peripheral surface portion 10A of the outer tube 10 is performed, for example, as follows. FIG.
As shown in FIG. 1, first, the large-diameter holding member 20 is attached to the inner peripheral surfaces of the inner tubes 30 and 31, and
The diameter of both ends is increased. Next, the inner tubes 30, 3
The tube 60 is inserted into the inner peripheral surface portion 10A of the outer tube 10 where the outer tube 1 is not fixed and the sliding member 5 is inserted into the tube.
0 is supplied and the sliding material 50 is sprayed. Thereby, the sliding material 50 can be easily attached to the inner peripheral surface portion 10A of the outer tube 10.
Can be applied.

The inner peripheral surface portion 10A of the outer tube 10
There is no particular limitation on the means for applying the sliding material 50 to, for example, a coating device in which a sliding material is included at the tip of a rod is prepared, and the tip of the coating device is attached to the inner peripheral surface portion 10A of the outer tube. The sliding material 50 may be applied by being inserted. The sliding material 50 is not applied to the inner peripheral surfaces of the inner tubes 30 and 31. The reason is that when the sliding material 50 is applied to the inner peripheral surfaces of the inner tubes 30 and 31, the inner tubes 30 and 31 can be easily slipped on the outer jacket of the cable and can be easily slipped on the inner tube of the inner tube 30 when they are attached so as to cover the cable connection portion. , 31 may enter the cable connection portion from between the inner peripheral surface of the cable and the jacket of the cable.

As described above, the insulating cover 1 in which the sliding material 50 is applied to the inner peripheral surface portion 10A of the outer tube 10 is inserted into one of the cables before connecting the cables as in the conventional case. After the cables are connected to each other, the insulating cover is pulled back onto the cable connection portion, and then the expanded diameter supporting member 20 is disassembled and removed. As a result, as shown in FIG. 3, the cable connection portion 80 is covered at substantially the center in the longitudinal direction of the outer tube 10, and the outer surface of the cable 90 (the cable insulating layer or Cable sheath).

[0021]

As described above, the insulating cover of the cable connection portion according to the present invention is a cable connection having a straight outer tube and inner tubes respectively arranged and fixed inside both end portions of the outer tube. In the insulating cover of the portion, since the inner tube is arranged and fixed on the inner peripheral surface of the outer tube where the inner tube is not fixed, the slipperiness between the inner peripheral surface of the outer tube and the outer jacket of the cable is reduced. As a result, the work of pulling back the insulating cover can be performed smoothly. For this reason, if the inner diameter of the outer tube does not need to be formed to be considerably larger than the outer diameter of the cable jacket, the cost is also reduced.

[Brief description of the drawings]

FIG. 1 is a half sectional view showing an embodiment of an insulating cover according to the present invention.

FIG. 2 is an explanatory view showing a state in which a sliding material is applied to the insulating cover of FIG. 1;

FIG. 3 is a half sectional view showing a state where the insulating cover of FIG. 1 is attached to a cable connection portion.

FIG. 4 is a half sectional view of a state in which both ends of a conventional insulating cover are expanded.

FIG. 5 is a half sectional view showing a state where the insulating cover of FIG. 4 is attached to a cable connection portion.

FIG. 6 is a front view showing another embodiment of the conventional insulating cover.

FIG. 7 is a half cross-sectional view of the previously proposed insulating cover.

8 is a half sectional view of a state in which both ends of the insulating cover of FIG. 7 are enlarged.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulation cover 10 Outer tube 20 Large diameter holding member 20 30, 31 Inner tube 50 Sliding material 80 Cable connection part 90 Cable

Claims (1)

[Claims] 1. An insulating cover for a cable connection portion having a straight outer tube and inner tubes disposed and fixed inside both ends of the outer tube, wherein the inner tube is not fixed. An insulating cover for a cable connection portion, wherein a sliding material is applied to an inner peripheral surface portion of the tube.