JPS582533B2 - Structure of the terminal part of the staff cable - Google Patents

Description

[Detailed Description of the Invention] The present invention provides a repeater storage enclosure inserted at regular intervals in the middle of a communication cable (hereinafter referred to as the cable) and a termination portion of a stub cable that connects the cable. It's about structure.

Conventionally, when connecting a communication cable repeater case and a stub cable, if the stub cable has a lead jacket, as shown in Figure 1, first the stub cable lead jacket 1 and the metal stub cable are connected. A lead work part 3 was created between the termination sleeve 2 and the lead work to ensure airtightness.

Furthermore, the airtightness within the termination sleeve 2 is ensured by injecting a thermosetting resin (epoxy or urethane) 4 into the termination sleeve 2 through the opening to seal the connections between the resin 4 and the cable core 5 and between the resin 4 and the cable sheath 1. The airtightness of the W surface was ensured by adhesion.

At this time, the airtightness between the cable core wire 5 and the resin 4 was ensured by stripping off the polyethylene coating of the core wire insulation and sufficiently adhering the cable core wire 5 and the resin 4.

In addition, the connection between the termination sleeve 2 and the shield body is through the gasket groove 2 of the flange installed on the outer periphery of the termination sleeve 2.
-1, an O-ring 6 is inserted to tighten the bolts between the body and the flange, and airtightness is achieved.

In order to facilitate the connection between the termination sleeve 2 and the stub cable sheath 1, the stub cable was purposely made of a lead sheath.

As a result, stub cables were heavy and difficult to handle, and were also inferior in terms of vibration and corrosion compared to plastic jackets.

In addition, if the stub cable has a plastic jacket such as LAP (a sheath in which an aluminum sheath is bonded to the inside of a polyethylene jacket), an auxiliary sleeve is attached to the center of the cross section of the termination sleeve 2, as shown in Figure 2. 2-2 Plastic jacket of stub cable (polyethylene jacket) 1-
There is an example in which a polyethylene mold 7 is used for No. 1, but it is expensive and has poor reliability in terms of water resistance.

Furthermore, to maintain airtightness between the outer surface of the plastic sheath 1-1 in the termination sleeve 2 and the resin 4, a tape 8 made of aluminum laminated with a hot-melt adhesive is used with the aluminum surface facing outward. There is an example in which airtightness is obtained by the adhesive force between the aluminum surface and the thermosetting resin 4, but in this case, the fusion between the aluminum surface and the plastic jacket 1-1 is uneven. However, long-term reliability was low, which was a practical problem.

In order to solve these problems at the connection between the shield body and the stub cable, the present invention uses a lightweight and inexpensive plastic jacket for the stub cable, and provides a termination sleeve at the tip of the stub cable. A gas dam is created by connecting with hot-melt adhesive and heat-shrinkable tubing and injecting thermosetting resin into this termination sleeve, making the termination smaller and smaller.
This is intended to be simplified and economical.

The present invention will be explained in detail below with reference to the drawings.

FIG. 3 is a longitudinal cross-sectional view of one embodiment of the present invention, 1-1
is a polyethylene jacket, 2 is a termination sleeve, 2-1 is a gasket groove in the flange part, 2a is an auxiliary sleeve, 2a-1
is the cable connection part of the auxiliary sleeve, 2a-2 is the chromate-treated part of the surface of the cable connection part of the auxiliary sleeve, 2a-3 is the resin adhesive part of the auxiliary sleeve, and 4 is the thermosetting resin (epoxy, urethane). ), 5 is a cable core wire (polyethylene or foamed polyethylene insulated core wire), 6 is an O-ring, and 9-1 is a hot-melt adhesive for metals (for example, ethyne-ethyl acrylate copolymer acrylic acid graft) bonded to the chromate-treated part. 9-2 is a heat-melting adhesive for polyethylene (for example, ethylene-ethyl acrylate copolymer), and 10 is a heat-shrinkable polyethylene tube.

FIG. 4 is a longitudinal sectional view of another embodiment of the resin bonded portion 2a-3 of the auxiliary sleeve shown in FIG. 3, and 2a-4 is a wave-shaped airtight retaining portion of the auxiliary sleeve.

The present invention provides an auxiliary sleeve 2 having a cable connection portion 2a-1 of the auxiliary sleeve and a resin adhesive portion 2a-3 of the auxiliary sleeve.
A thermosetting resin (epoxy, urethane) is injected into the cylindrical termination sleeve 2, which is joined at the center of the termination sleeve 2, to create a gas dam, and a gas dam is placed on the outer periphery of the termination sleeve 2 for connection to the body. This is a termination with a flange attached for the purpose.

The termination sleeve 2 is made of nickel-plated brass or stainless steel, and has anti-corrosion measures to withstand use inside a manhole.

The cable connection portion 2a-1 of the auxiliary sleeve 2a is coated with a chromate treatment 2a-2 on the outer surface and a metal adhesive 9-1 of a hot-melt adhesive (e.g. ethylene-acrylic acid copolymer acrylic acid graft modification). is preliminarily adhered to the chromate-treated surface 2a-2.

The auxiliary sleeve portion 2a having the adhesive 9-1 is fixed to the stump cable 1-1, and a heat-melting adhesive (e.g. Ethin-ethyl acrylate copolymer) 9-2
Wrap with polyethylene adhesive.

Next, the heat-shrinkable polyethylene tube 10, which has been drawn through the stub cable in advance, is heated on the hot-melt adhesive 9-2 to shrink the heat-shrinkable tube 10.

At the same time, the heat-melt adhesive for polyethylene 9-2 is melted at a temperature of about 140°C, and after cooling, the heat-melt adhesive for metal 9-1 and the heat-shrinkable tube 1 are placed in the auxiliary sleeve 2a.
Glue with 0.

In the polyethylene jacket part 1-1, the polyethylene jacket 1-1
and adhere to the heat shrink tube 10.

The resin adhesive part 2a-3 of the auxiliary sleeve 2a is made of thermosetting resin (
(Epoxy, urethane) 4, and even if this bonded part is subjected to heat cycles, the resin covers the metal from the outside, so the adhesiveness between this metal part and the resin 4 can be expected to be sufficient.

In this case, if the structure of the resin bonding part 2a-3 is made into the wave shape 2a-4 shown in FIG. 4, the bonding area with the resin against the gas leakage route becomes large, and the reliability of airtightness can be sufficiently increased. .

On the other hand, when connecting the cable core 5 and the thermosetting resin (epoxy, urethane) 4, if polyethylene or foamed polyethylene is used for the core wire insulation, the insulation coating must be removed, or the polyethylene-based The wire is connected to an insulated core wire coated with a melt-adhesive resin (for example, ethyne-vinyl acetate-glycidyl methacrylate terpolymer), and bonded to the thermosetting resin 4.

In this way, the airtightness of the termination part is ensured by ensuring the airtightness of the interface between the injected thermosetting resin 4 and the cable core wire 5, and the adhesion with the resin 4 at the resin bonding part 2a-3 of the auxiliary sleeve 2a. Gas-tightness is ensured by the adhesiveness between the heat-melting adhesives 9-1 and 9-2 and the heat-shrinkable tube 10 at the cable connection portion 2a-2 of the auxiliary sleeve 2a.

The connection between the cover body and the termination sleeve 2 is through a gasket groove 2 cut into the flange attached to the outer circumference of the termination sleeve.
By inserting the O-ring 6 into -1, airtightness is ensured by the bolt force between the flange and the shield.

The structure of this termination section is as follows: (1) The connection section between the termination sleeve and the stamped cable can be made smaller. (2) Two or more strips of stamp cable can be drawn out from one flange. (3) The connection section can be made smaller. It has advantages such as high reliability and (4) inexpensive connection method.

As explained above, in the structure of the termination part according to the present invention, an auxiliary sleeve consisting of a cable connection part having a hot-melt adhesive layer on the outer surface and a part bonded to the gas dam resin is attached to the auxiliary sleeve on the central outer periphery. It is attached to a termination sleeve with an inner diameter larger than the outer diameter, and uses heat-melt adhesive and heat-shrinkable polyethylene tubing to connect to the cable jacket, and resin is bonded to the auxiliary sleeve to improve the airtightness of the gas dam. Since the connection to the conventional cable is made of lead, compared to the method of using a lead jacket for the stamped cable jacket and the connection method of polyethylene mold in the case of a polyethylene jacket, It is highly reliable against corrosion and vibration at the edges, and has the advantage of being compact and economical.

In addition, the stamped cable can be covered with plastic, which can be expected to improve workability and reliability.

[Brief explanation of the drawing]

1 and 2 are longitudinal sectional views of a conventional termination part, FIG. 3 is a longitudinal sectional view of one embodiment of the present invention, and FIG. 4 is another embodiment of the resin connection part of the auxiliary sleeve according to the present invention. FIG. 3 is an example vertical cross-sectional view. DESCRIPTION OF SYMBOLS 1... Lead sheath of the stub cable, 1-1... Plastic sheath of the stub cable, 2... Termination sleeve, 2a... Auxiliary sleeve, 2-1... Gasket groove , 2a-1... Cable connection part of auxiliary sleeve, 2
a-2... Chromate treated part of the cable connection part of the auxiliary sleeve, 2a-3... Resin bonded part of the auxiliary sleeve,
2a-4... Wave-shaped resin adhesive part of auxiliary sleeve, 3.
... Lead work part, 4 ... Thermosetting resin, 5 ... Cable core, 6 ... O ring, 7 ... Polyethylene mold, 8 ... Laminate tape, 9-1 ... Heat-melting adhesive, 9-2... Heat-melting adhesive, 10... Heat-shrinkable polyethylene tube.

Claims (1)

[Claims] 1 One end of the sleeve is an open end for drawing out the cable core wire and injecting the thermosetting resin for creating the gas dam, and the other end has an outer diameter smaller than the inner diameter of the sleeve and an inner diameter that is equal to the outer diameter of the cable jacket. A termination sleeve, which is integrated approximately in the center of the matching auxiliary sleeve and further has a fixing flange around the outer periphery of the sleeve, is attached to the end of the plastic cable jacket, and is attached to the end of the plastic cable jacket. A stub characterized in that the cable side part and the cable sheath are bonded together using a hot-melt adhesive and a heat-shrinkable tube, and a thermosetting resin is injected into the sleeve to form a communication cable cassdam. Structure of cable termination.