JPS63171111A - Tip of plastic cable for laying - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to the use of plastic cables for laying high voltage plastic cables, etc. to installation routes that are difficult to reach, such as conduits with many bends, steps, or narrow areas. This relates to the tip of the cable for installation.

[Prior Art] High-voltage plastic cables and the like have a thick coating layer on a conductor such as an insulator, and the coating layer has high rigidity, so it is extremely difficult to straighten the cable once it has bent. By the way, for example, when a drum-wound plastic cable is installed on a wiring route that has many bends, steps, or narrow areas, the bending tendency of the tip of the cable may interfere with the installation. In such a case, the bend in the tip of the cable is removed by a mechanical method or the like before the cable is laid, and a restraining device is attached to the tip of the conductor of the cable on the LC, and the cable is pulled and laid with a rope.

[Problems to be Solved by the Invention] However, the method of straightening the bends at the tip of the plastic cable before laying it takes a lot of time and effort to straighten the bends, and the cable is likely to be damaged. Furthermore, when high-voltage plastic cables are installed in conduits that are difficult to access, there are bends in the installation route with extremely small bending radii, or narrow passages where the inside diameter is slightly larger than the outside diameter of the cable. If there is a stepped portion or the like, it is difficult to install the cable even if the bend in the tip of the cable is corrected in advance, for example. The present invention has been made to solve this problem, and aims to provide a plastic cable installation tip part that allows cables to be easily installed even on the installation route with poor conditions as described above.

[Means for solving the problem] The above problem is caused by the lack of flexibility at the tip of the plastic cable. In other words, if the tip of the cable to be laid is flexible, the cable can be laid. Focusing on the fact that the cable can easily pass through bends, steps, narrow areas, etc. in the route, and that the lack of flexibility at the cable tip is due to the rigidity of the cable coating layer, A predetermined length of the coating layer at the tip of the cable is removed to form the tip so that the tip can be bent. That is, the distal end portion of the plastic cable of the present invention for installation includes an exposed cable conductor portion formed by removing a predetermined length of the coating layer on the cable conductor from the distal end portion, and a cable conductor exposed portion formed at the rear of the exposed cable conductor portion. The cable is characterized by comprising a sloped coating layer and a retainer attached to the tip of the cable conductor.

"Function 1: Since the tip of the plastic cable is flexible, the plastic cable easily follows the movement of the tow rope connected to the anchoring part. Also, since there is a sloped coating layer, the conductor is exposed. The cable at the rear of the part follows the cable easily, and the cable can be pulled even if there is a small diameter step etc.) There is no explanation.

[Example] An example of the distal end portion for installation of a plastic cable of the present invention will be described with reference to the drawings. 2 is a conductor of a plastic cable 1 made of a large number of copper wires twisted together; 3 is a cable covering layer made of a crosslinked polyethylene insulator and a polyvinyl chloride sheath. As shown in the figure, the plastic cable 1 has a cable conductor exposed portion 2 in which the cable sheathing layer 3 of a predetermined length is removed from the tip of the plastic cable 1 toward the rear.
A is provided. The cable conductor exposed portion 2a has a length such that the cable conductor 2 in this portion has enough flexibility to easily bend. This length depends on the outer diameter of the cable to be laid, the conditions of the laying route, etc., but it is preferably 50 cm or more, excluding the portion required for attaching the retainer 5, which will be described later. On the other hand, the cable covering layer 3 has vI of the cable conductor exposed portion 2a.
A sloped covering portion 3a having a predetermined length is formed from the end to reduce the difference between the outer diameter of the cable conductor exposed portion 2a and the outer diameter of the covering layer 3. The slanted covering portion 3a has the effect of reducing the possibility of the cable being caught in a narrow space during installation. 5 is a retainer attached to the tip of the cable conductor 2; 4 is a heat shrink tube that is coated from the retainer 5 to the cable conductor exposed portion 2a1, the inclined sheathing portion 3a, and the sheathing layer 3; It has the purpose of waterproofing and dustproofing the cable conductor 2a or the sloped covering portion 3a, etc. exposed by the removal. Therefore, polyvinyl chloride tape or the like may be wrapped in place of the heat-shrinkable duplex 4, but such coating treatment is not essential for implementing the present invention, and depending on the situation, the cable may be laid without such coating treatment. It is also possible. In addition, after the cable conductor exposed portion 2a,
This does not mean only a state in which all of the covering on the cable conductor 2 has been removed, but also includes a state in which a pressing tape or the like is present on the conductor and the conductor is not directly exposed.

Next, when a plastic cable is laid using the cable laying tip constructed as described above, a tow rope is connected to the anchoring device 5 and hoisted with a winch or the like in the same manner as in normal cable laying. Since a large coating layer is peeled off by a predetermined length from the tip of the cable and the cable conductor 2 is made up of a plurality of twisted wires and is flexible, the cable can easily follow the towing rope. Therefore, even if there are bends, narrow steps, etc. in the laying route, there will be no cases where the cable tip gets caught and the cable cannot be laid.

[Effects of the Invention] As described above, the distal end of the plastic cable of the present invention is provided with a predetermined cable conductor exposed portion that is easy to bend, so it is suitable for laying routes with many bends, steps, narrow areas, etc. Also, cables can be easily laid, and the industrial value is extremely large.

[Brief explanation of the drawing]

The accompanying drawing is an explanatory view of one embodiment of a distal end portion for laying a plastic cable according to the present invention. 1 Niblast cable, 2: Cable conductor, 2a: Cable conductor exposed portion, 3: Cable covering layer, 3a: Slanted covering portion, 4: Heat shrink tube, 5: Fastener.

Claims (1)

[Claims] (1) A cable conductor exposed portion which is made easy to bend by removing a required length of the coating layer on the cable conductor from the tip portion, and an inclined coating portion formed at the rear of the cable conductor exposed portion; 1. A tip for laying a plastic cable, characterized by comprising a retainer attached to the tip of a cable conductor.