JPS6111957Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a sealing structure for a branch connection of a communication cable or the like having a plastic jacket.

2. Description of the Related Art Conventionally, when a branch connection is made in a communication cable having a plastic jacket, an example of a structure for sealing the connection is shown in FIG. After connecting each cable 1, 2 with the auxiliary sleeves 3, 3 and branch adapter 4 fitted to the disassembled main cables 1, 1 and branch cable 2, the branch adapter 4,
4 is covered with a half-split aluminum sleeve 5, and a heat shrink sheet (or heat shrink sleeve) 6 is placed on top of it.
After covering and fixing with fasteners 7, the heat-shrinkable sheet 6 and the auxiliary sleeve 3 are respectively heat-shrinked to cover the cables 1 and 2 together. That is, when the outer sheath of each cable 1, 2 is made of a heat-meltable material such as polyethylene, the branch adapter 4, the auxiliary sleeve 3, and the inner layer of the heat-shrinkable sheet can be heat-sealed to the cable outer sheath. The contact portion is made of a similar material (for example, the same material), and after the contact portion is melted during heating, an integrated sealed structure can be obtained by cooling.

This structure has the advantage of providing excellent sealing performance, shortening work time, and being simple. However, when you want to branch off the branch cable 2 from the existing cable, or change the connection part, it is difficult to use. If this is the case, there is a problem in that the branch adapter 4 cannot be attached unless the main cable 1 or all the connections are disconnected, and it is necessary to prepare in advance the branch adapter 4 that corresponds to the cable dimensions, number of branches, etc. There were some problems.

In addition, in Japanese Patent Application Laid-open No. 54-129384, the second
Using clips 8 as shown in Figure A, insert the heat shrink sleeve 6 into the slit 9 between each cable 1,2.
A proposal has been made to improve workability and adhesion by sandwiching and heat-shrinking the material as shown in FIG. 2B.
However, with this technology, each of the cables 1 and 2 that are brought close to each other is covered with a heat shrinkable sleeve 6, and the tension of the sleeve 6 is suppressed by the clip 8, so the distance between each cable 1 and 2 is Connect each cable 1 and 2 as narrowly as possible.
If the sleeve is not fixed in place, tension will always be applied to the heat-shrinkable sleeve 6, stress will be concentrated on the heat-sealed part and the sleeve will peel off, resulting in loss of sealing properties and the opening of the slit 9 of the clip 8. There were some problems, such as the risk of damage.

This idea was made based on the above background, and each cable protruding from the connection part is fitted with a concave groove of an intervening spacer whose surface is made of a material that can be fused, and a heat-shrinkable sleeve is placed over the concave groove. The object of the present invention is to obtain a sealed structure for a branch connection part that improves workability and sealing performance by fusing and integrating the mutually contacting parts when the joints are heated and shrunk.

This invention will be explained below based on an embodiment shown in FIGS. 3 to 5.

What is indicated by the reference numeral 10 in the figure is an intervening spacer to be inserted between the main cable 1 and the branch cable 2 pulled out from the branch connection. The surface of this intervening spacer 10 is made of a material that can be fused to the inner layer of each cable 1, 2 and the heat-shrinkable sleeve (or heat-shrinkable sheet) 6 (for example, a material such as uncrosslinked polyethylene in the case of a polyethylene-sheathed cable). Arc-shaped outward facing grooves 11 and 12 are formed on both sides (top and bottom in FIG. 3) for fitting each cable 1 and 2, and grooves 11 and 12 are formed near both edges of the grooves 11 and 12. Projections 13 are formed respectively.

Moreover, the inside of the intervening spacer 10 (the grooves 11, 1
2) are filled with filling members 14, 14 made of a material with good thermal conductivity (such as steel).
is buried. One end of this filling member 14 is covered with one end of the intervening spacer 10, as shown in FIG. 3B, and the other end is flush with the other end of the intervening spacer 10. Note that the filling member 14 in the intervening spacer 10 preferably follows the shape of the grooves 11 and 12, and does not need to be particularly divided.

Each cable 1, 2 protrudes from a branch connection using an intervening spacer 10 having such a configuration.
To seal the branch connection, first wrap insulating tape around the branch connection or fit a halved spacer to reduce the sharp protrusions as shown in Figure 4. , each cable 1, 2
In between, the intervening spacer 10 is inserted with the end (one end) sealed with the filling member 14 facing the branch connection part, and the cables 1 and 2 are connected to each recess so as to spread the cables 1 and 2. The grooves 11 and 12 are connected to the concave groove 11,
12 are fitted together.

Next, a half-split aluminum sleeve 5 is placed over the branch connection, and a heat-shrinkable sheet (initial connection work In this case, a heat-shrinkable sleeve may be used) 6) and heat.

This heating causes the heat-shrinkable sheet 6 to shrink,
The aluminum sleeve 5, each of the cables 1 and 2, the intervening spacer 10, etc. are in close contact with each other to create a sealed state. In addition, if the inner layer of the heat-shrinkable sheet 6, the outer sheath of each cable 1, 2, the surface of the intervening spacer 10, etc. are melted by heating, and there is a gap between each contact part, the melted fluid will flow into the capillary. Due to this phenomenon, it gradually flows into the gap and fills it. At this time, the filling member 14 is filled with the concave groove 11, which causes poor heat transfer.
The projection 13 acts to uniformize the melting phenomenon by transferring heat to the vicinity of the cables 1, 2 and the grooves 11, 12 of the intervening spacer 10 by melting itself. It acts to fill the space that tends to be left between it and the side wall.

Thereafter, when each part is cooled, the molten fluid solidifies (fuses), and the cables 1 and 2, the heat-shrinkable sheet 6, and the intervening spacer 10 are integrated as shown in FIG. As a result, airtightness occurs in the vicinity of the intervening spacer 10 in the lengthwise direction of the cable.
Furthermore, since one end of the filling member 14 is covered with synthetic resin as shown in FIGS. 3B and 4, even if the filling member 14 is not made of a breathable material, Directional airtightness is not compromised.

On the other hand, when reconnecting the cables, cut the heat-shrinkable sheet 6 and divide the aluminum sleeve 5 into two, change the connection, and use the heat-shrinkable sheet fused to both cables 1 and 2. 6 and the intervening spacer 10 may be reheated and melted and replaced with a new one, and the sealing operation may be carried out in the same manner as described above. At this time, only a portion of the connection portion may be disassembled. In either case, the outer peripheral shape of the heat-shrinkable sheet 6 in the vicinity of the airtight main part has a shape similar to a circle, such as an ellipse, as shown in FIG.

As explained above, this invention is characterized by sandwiching an intervening spacer between the cables, surrounding it with a heat-shrinkable sheet, and heating and fusing the mutually contacting parts, thereby completing the branch connection. Since you only need to attach the intervening spacer and heat-shrinkable sheet later, it is suitable for dismantling and changing only the necessary parts of the branch connection, or increasing or decreasing the number of branch cables, increasing work efficiency. be able to. In addition, since the outer shape follows the intervening spacer and the outer circumferential shape of the cable, it is possible to reduce unnecessary tension acting on the heat-shrinkable sheet, and it also prevents the outer sheath of the cable from causing poor heat transfer during heating. Heat is transferred to the contact area with the concave groove via the filling member, which creates an effect that evens out the melting phenomenon, allowing even heat fusion to occur and improving durability. effective.

[Brief explanation of the drawing]

Fig. 1 is a partially sectional perspective view showing one conventional example, and Fig. 2 shows another conventional example, in which A is a perspective view of the clip, B is an explanatory diagram of how to use the clip, and Fig. 3 is a perspective view of a conventional example.
5 to 5 show an embodiment of this invention, FIG. 3A is a front view of the intervening spacer, and FIG. 3B is a front view of the intervening spacer.
is a plan view, FIG. 4 is a partially sectional side view of the main part, and FIG. 5 is a sectional view taken along the line - in FIG. 4. 1... Main cable, 2... Branch cable, 6...
... Heat shrinkable sheet (heat shrinkable sleeve), 10 ... Intervening spacer, 11, 12 ... Concave groove, 13 ... Projection, 14 ... Filling member.

Claims (1)

[Scope of claim for utility model registration] (i) Each cable 1 pulled out from the branch connection,
An intervening spacer 10 whose surface is made of a material that can be fused is sandwiched between the cables and the intervening spacer, and each cable and the intervening spacer are covered with a heat shrink sleeve 6.
These mutually contacting parts are integrated by heat fusion, and the intervening spacer 10 includes:
Concave grooves 11 and 12 for fitting each cable
is formed, and a filling member 14 is provided near the grooves 11 and 12 to promote heat transfer at the contact portion with the cable jacket during heat fusion. Sealed structure for cable branch connections. (ii) Sealing of a plastic-sheathed cable branch connection section according to claim 1, characterized in that at least one end of the filling member 14 is sealed by an end of the intervening spacer 10. structure.