JPS633530B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for coating connections, etc. of cables having a plastic jacket.

Conventionally, the method of covering cable connections and the like has been carried out by covering the cable jacket with a material that is the same as or suitable for the cable jacket material, as the material of the cable jacket changes. For example, lead sheathing has been used when the cable sheath is lead, and polyvinyl chloride heat shrink sleeves have been used when the cable sheath is made of polyvinyl chloride. Currently, polyethylene is said to be extremely superior in terms of weather resistance and chemical resistance as an outer covering material, but on the other hand, polyethylene itself has the disadvantage of not being made of adhesive. Establishing a means of connecting the jacket is a technical issue.

As a conventional example of a method of covering the connection portion of a cable having a polyethylene jacket with a polyethylene heat-shrinkable sleeve, the method shown in FIG. 1 has been proposed.

In Fig. 1, the symbol 1 indicates a cable;
The reference numeral 2 indicates the connecting portion. The outer sheath of this cable 1 is made of plastic, for example polyethylene, and a spacer 3 made of polyethylene is fitted into the outer sheath of this cable 1, and a welding material is used to ensure airtightness of each contact surface. (Polyethylene) 4 is melted to create cable 1.
and spacer 3 are integrated, and 2
A stepped portion 5 is formed on the outer peripheral surface of each spacer 3, and an aluminum pipe 6 is fitted into this stepped portion 5. Then, a polyethylene heat-shrinkable sleeve 7 is placed to cover the spacer 3, aluminum pipe 6, and spacer 3, and heat shrinkage is performed so that the sleeve 7 becomes the outer sheath of the cable 1 and the spacer 3. 3. It is configured to be in close contact with the aluminum pipe 6, etc.

"Problems to be Solved by the Invention" However, in the conventional example with this configuration, when it becomes necessary to repair or reconnect a part of the connection part 2 of the cable 1, the heat shrinkable The sleeve is cut to expose the aluminum pipe 6, and the vicinity of the stepped portion 5 of the spacer 3 is scraped off to shift the aluminum pipe 6 in the length direction of the cable 1, and the intended reconnection to the connection portion 2 is performed. After this is completed, the aluminum pipe 6 is aligned with the spacer 3 again, and then a self-adhesive tape or the like is wrapped around the outer periphery of the spacer 3 and the aluminum pipe 6, etc., to form the original heat-shrinkable spacer 7 shown in FIG. It was necessary to replace it with a new one, which resulted in problems such as its airtightness being lower than originally, and the taping work etc. being extremely troublesome.

This invention was made in view of the above circumstances,
The purpose is to provide a method for reconnecting plastic cable sheaths that can ensure sufficient airtightness and has good workability.

"Means for Solving the Problems" In order to solve the above problems, the present invention provides a heat shrinkable sleeve that fits over a metal pipe and both ends thereof when reconnecting a cable connection covered with a heat shrink sleeve. Cut the heat shrink sleeve open near the connection point with the plastic spacer, and
After removing this heat-shrinkable sleeve and metal pipe and performing work such as repairing the connection, a metal pipe is placed over the connection, and the metal pipe and spacers are placed on both ends of the metal pipe and then heated again. It is designed to be covered with a shrinkable sleeve and shrink by heating.

"Operation" By cutting the heat-shrinkable sleeve near the fitting portion between the metal pipe and the spacer, the split-structure metal pipe can be easily removed from the spacer to expose the connecting portion.

"Embodiments" Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that parts in the figure that are common to the example of FIG. 1 are given the same reference numerals to simplify the explanation.

FIG. 2 shows the overall configuration of a cable connection part to be reconnected by applying the present invention, in which the plastic sheath of the cable 1, for example, the polyethylene sheath, and the 2
Two polyethylene spacers 3 are fitted facing each other, and a metal pipe 10 shown in FIG. 3 is in contact with the stepped portion 5 of these two spacers 3. This metal pipe 10 is divided into two as shown in the illustrated example, and by fitting into the stepped portion 5 of the spacer 3, a cylinder having a slight distance between it and the connecting portion 2 of the cable 1 is formed. A reinforcing layer is formed around the connection part 2, and is made of highly conductive metal materials such as aluminum and copper so that it also functions as a shield layer to reduce internal and external noise interference. It is configured.

Further, a heat-shrinkable double sleeve 20 shown in FIG. 4 is inserted over the spacer 3, the metal pipe 10, and the outer sheath of the cable 1 near these, and is integrated with these by heating and shrinking. is fused to. The heat-shrinkable two-layer sleeve 20 has an inner layer 21 made of uncrosslinked polyethylene, etc., which can be heat-sealed to the jacket of the cable 1 and the spacer 3, and an outer layer 22, which can be heat-shrinkable in the circumferential direction. It is made of stretched cross-linked polyethylene or the like, and is configured to be heat-shrinkable at a temperature at which the inner layer 21 melts. In addition, the inner layer 21 and the outer layer 22 are laminated together, a part of which is cut out in the longitudinal direction, and bent outward along the longitudinal direction near the cut 23, so that the inner layer 21 is mutually laminated. Opposed welding surfaces 24
is formed, and on the opposite side of this welding surface 24,
A reinforcing material 25 having good heat resistance is provided along the length direction.

In FIG. 4, the reference numeral 26 indicates a temperature-indicating paint applied to the outer circumferential surface of the heat-shrinkable two-layer sleeve 20, and the reference numeral 27 indicates a rod-shaped member disposed along the reinforcing material 25, 28. A clip shown by is a clip that presses the welding surface 24 through the rod-shaped member 27.

Hereinafter, a connection method when the connection portion 2 of the cable 1 is coated with the initial coating will be described.

First, with the ends of cable 1 facing each other,
A spacer 3 is fitted into the outer sheath of each cable 1 so that the stepped portions 5 thereof face each other, and the cables 1 are connected and coated to form a connecting portion. Next, the two divided metal pipes 10 are brought into contact with the step portions 5 of the two spacers 3 to align the cable 1 in the length direction, and then the spacers 3 are fixed to the cable sheath as necessary. do. Next, a heat-shrinkable two-layer sleeve 20 is attached to the outer peripheral surface of the metal pipe 10.
are opened from the cut 23 and covered, and the welded surfaces 24 are brought together as shown in FIG. 4, and the welded surfaces 24 are held by the clips 28 via the rod-shaped member 27, so that the welded surfaces 24 are pressed.

Next, the heat-shrinkable two-layer sleeve 20 is heated with a gas burner or a torch lamp to heat-shrink the outer layer 22 and melt the inner layer 21 to be fused to the outer peripheral surface of the spacer 3 and the outer sheath of the cable 1, respectively. , are integrated as shown in Figure 2. At this time, the inner layer 21 is fused to the spacer 3 and the cable 1, but the outer layer 22, which is more heat resistant than the inner layer 21, is easily contracted by the melting phenomenon of the inner layer 21, as shown in FIG. The situation will be like this. Further, the temperature-indicating paint applied to the surface of the heat-shrinkable two-layer sleeve 20 has the effect of making it easier to control the heating temperature. After the welding surface 24 of the heat-shrinkable two-layer sleeve 20, the outer sheath of the cable 1, the space between the spacer 3 and the inner layer 21, etc. are cooled and stabilized, the clip 28 and rod-shaped member 27 shown in FIG. Once removed, it is ready for use as shown in FIG.

On the other hand, to explain the case where the connection part 2 of the cable 1 is reconnected, as shown by chain lines A and B in FIG. 20 is cut open to remove the coating on the outer periphery of the metal pipe 10, and the metal pipe 10 is completely removed while being divided to expose the connecting portion 2 as shown in the upper half of FIG. At this time, since the metal pipe 10 and the spacer 3 are simply fitted together, they can be easily divided and dismantled by simply removing the heat-shrinkable two-layer sleeve 20. After performing connection processing.
The metal pipe 10 is brought into contact with the stepped portion 5 of the spacer 3,
A material similar to the heat-shrinkable two-layer sleeve 20 described above is placed around the outer periphery of the sleeve and heated to cause heat-sealing and heat-shrinking.

At this time, the spacer 3 to be heat fused or
The spacer 3 and the inner layer 21 heat-sealed to the cable 1
By exposing the necessary dimension in the length direction of 2
5th by another heat shrinkable double layer sleeve
As shown in the lower half of the figure, the outer circumferential surface of the original heat-shrinkable two-layer sleeve 20 fused to the outer sheath of the cable 1 and the outer circumferential surface of the spacer 3, the outer circumferential surface of the spacer 3, and the outer circumferential surface of the metal pipe 10. The inner layer 21 of the heat-shrinkable two-layer sleeve 20 is fused or adhered to each of the sleeves to form a sealed state.

Furthermore, when exposing the connection part 2 three or four times, the coating is cut open and the metal pipe 1 is exposed in the same manner as described above.
Divide 0 and refit to create heat-shrinkable two-layer sleeve 2
By covering it with 0 and heating it, it can be repeatedly disassembled and assembled.

In addition, in the above-mentioned embodiment, the cable 1,
Although polyethylene is used as the material for forming the spacer 3 and the heat-shrinkable two-layer sleeve 20, other plastics may be used as long as they satisfy the conditions of being heat-sealable and heat-shrinkable in the circumferential direction. You can also replace it with something like Further, the detailed configurations of the spacer 3, the metal pipe 10, etc. are not limited to those shown in the drawings.

"Effects of the Invention" As is clear from the above description, the present invention has the advantage of cutting the heat-shrinkable sleeve surrounding the metal pipe in the vicinity of the joint between the split-structure metal pipe and the spacer that abuts both ends of the metal pipe. Because the heat-shrinkable sleeve is removed, the connection can be easily exposed and repaired, and after the repair is completed, the split structure can be removed. By simply attaching the metal pipe to the spacer, then wrapping and heating a heat-shrinkable sleeve over both the spacer and the metal pipe, the same airtightness as in the original connection can be achieved. It has the effect of being able to.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an example of a conventional cable connection section, and FIGS. 2 to 5 show examples of cable connection sections connected or reconnected by applying the method of the present invention. Figure 2 is a longitudinal sectional view showing the overall structure, Figure 3 is an exploded perspective view of the metal pipe, Figure 4 is a perspective view illustrating an example of the use of a heat-shrinkable two-layer sleeve, and Figure 5 is an example of a work. FIG. 1...Cable, 2...Connection part, 3...Spacer, 1
0...Metal pipe, 20...Heat-shrinkable two-layer sleeve,
21... Inner layer, 22... Outer layer, 23... Cut, 24
...Welding surface.

Claims (1)

[Claims] 1 A spacer attached to the plastic jacket so as to sandwich the connection part of a cable having a plastic jacket and face each other, and a spacer arranged with the same central axis between these two spacers and divided vertically. After wrapping a heat-shrinkable sleeve around the outer periphery of the splittable metal pipe, the heat-shrinkable sleeve is shrunk by heating to connect the plastic cable sheath, and then when the connection is repaired, the metal pipe is The heat-shrinkable sleeve is cut into slices near both ends in the length direction, the heat-shrinkable sleeve in the section of the sliced portions at both ends is cut lengthwise, and the heat-shrinkable sleeve and the metal pipe are removed. After exposing the cable connection and completing the repair, cover the connection with a pipe, wrap a heat-shrinkable sleeve around the covered metal pipe and the spacers on both sides, and remove the heat from the wrapped metal pipe. A method for reconnecting a plastic cable sheath, characterized by heating and shrinking a shrinkable sleeve.