JPH0561845B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of laying a prefabricated indoor trunk cable for branching a branch cable for power supply to each floor of a building, for example.

[Conventional technology]

Conventionally, the above-mentioned installation method involves removing the insulating layer at a predetermined intermediate portion of the indoor trunk cable and attaching a branch line connecting fitting such as a branch sleeve to the exposed conductor by compression connection, etc. The metal attachment part is covered and protected with rubber or plastic tape, then wound around a drum and shipped, pulled into a predetermined position indoors such as a building, and installed. After pulling in, peel off the rubber and plastic tape coatings mentioned above, and connect the branch cable directly to the branch connection fitting or via a branch connection fitting equipped with a branch line attachment terminal mounted on the branch connection fitting. death,
Thereafter, the branch cable connection portion, including the exposed conductor portion of the main cable, is insulated by wrapping it with rubber or plastic tape.

If the branch cable is a single wire and small in size, sometimes when a branch sleeve is crimped onto the exposed conductor of the main cable, the conductor of the branch cable is also compressed all at once by the sleeve, and the branch connection is After being insulated by molding with rubber or plastic tape or wrapping with tape, it may be wound around a drum, shipped, and then taken indoors.

[Problem to be solved by the invention]

In the above-mentioned conventional normal cable installation method, the proportion of factory processing is small, and after installation indoors, at the installation site, the rubber and plastic tape protecting the branch cable connection fittings are removed, the branch cable is connected, and the conductor of the main cable is removed. It is necessary to construct an insulating coating by wrapping rubber or plastic tape over the entire branch line connection part, including the exposed part, which unfortunately requires a large number of processing steps at the installation site.

In addition, when running trunk cables indoors,
It is often difficult to pull in a branch line connecting fitting that is attached to the side member or cross member of a cable rack, or to a through hole in a floor or wall, and is attached to the middle of the main cable and protrudes from the side of the cable. do not have.

For this reason, as mentioned above, branch fittings with branch line attachment terminals that protrude to the side are sometimes installed after the cable has been drawn in, but in this case, the processing required at the installation site increases accordingly. .

Furthermore, when a trunk cable connected to the branch cables described above is shipped and brought indoors, the insulating layer of the branch connection part is hooked onto the cable rack or through hole, which is likely to cause damage to the insulating layer. . In order to avoid this, if the insulation at the branch connection part is installed after the cable is drawn in, the processing at the installation site will increase accordingly.

The present invention has been made in view of the above points, and is an indoor main line that reduces the processing required at the cable installation site and eliminates the risk of branch line connection fittings etc. being caught in cable racks, floors, and through holes in walls when indoors. This proposal proposes a cable installation method.

[Means to solve the problem]

The indoor trunk cable installation method of the present invention that achieves the above object includes the process of removing the insulating layer at a predetermined intermediate portion of the cable and attaching the branch line connecting fitting 2 to the exposed conductor 10, and the process of attaching the branch line connecting fitting 2 to the exposed conductor part and the branch line connecting fitting. A branch line connecting fitting protrudes from an indoor trunk cable 1 that has been previously processed to provide an insulating coating layer 3 for insulating the attachment portion so as to cover the entirety of the insulating coating layer 3 and the branch line connecting fitting 2. A removable protective cover 4 of a vertically split type, which is provided with a tapered surface 40a at the front end that is wide in the direction in which the cable is located, and whose width narrows toward the front, is attached, and then the indoor trunk cable 1 can be brought indoors. This is characterized in that the protective cover 4 is removed after the indoor operation is completed.

[Explanation of Examples]

Hereinafter, details of the present invention will be explained based on the drawings.

In Fig. 1, 1 is an indoor trunk cable such as a rubber or plastic insulated flat conductor cable.
At a predetermined intermediate portion corresponding to a branch cable connection portion, for example, in the case of a vertically laid trunk cable that branches at each floor of a building, the cable insulation layer 10a is peeled off at predetermined intervals to expose the cable conductor 10. Next, as shown in FIG. 2, a branch line connecting fitting 2, which is formed by engaging a main body 2a provided with a branch line connecting terminal 21 and a cover piece 2b with each other, is attached by compression connection or the like. Then, the conductor exposed part and the conductor 1 of the branch line connection fitting 2
An insulating coating layer 3 of rubber or plastic tape is applied, for example, by a molding method using a polyvinyl chloride resin or a taping method using a butyl rubber insulating tape so as to cover the attachment portion to the 0.

A protective cover 4 is attached to the indoor main cable 1 so as to entirely cover the insulating coating layer 3 and the branch line connection fitting 2. As shown in FIG. 1, the protective cover 4 is formed to be wide in the lateral direction from which the branch line connection fitting 2 protrudes, and as shown in FIG. 3A.
As shown in the side view of FIG. 3B and the cross-sectional view of FIG. 3C, the upper cover 41 and the lower cover piece 42
are connected in a hinged manner with a pin 43, and both cover pieces are fastened with bolts 44. bolt 4
4 is a terminal hole 210 of the above-mentioned branch line connection terminal 21
The protective cover 4 is fixed to the branch line connection fitting 2. At both front and rear ends of the protective cover 4, there are tapered surfaces 40a, 40a whose left and right widths decrease toward the front or rear, and tapered surfaces 40 whose upper and lower thicknesses decrease toward the front or rear.
b, 40b (the taper angle is 15~
30 degrees). Suitable materials for the protective cover 4 include those that are lightweight and have a slippery surface, such as aluminum alloy or hard resin (such as polyester premixes or ABS resin).

According to the indoor trunk cable installation method of the present invention, the process of attaching the branch line connection fitting 2 and the process of applying the insulation coating layer 3 to the indoor trunk cable 1 are performed in advance in the factory, Furthermore, before the indoor trunk cable 1 is shipped from the factory, the above-mentioned protective cover 4 is applied to the indoor trunk cable in the factory so as to completely cover the insulation coating layer 3 and the branch line connection fittings 2 as described above. . Thereafter, the cable is wound around a drum and transported to an indoor cable installation site, for example, inside a high-rise building, and while the cable 1 is unwound from the drum, it is pulled by a lead-in wire to follow a predetermined installation route inside the building. Pull in and extend the line. During this indoor lead-in, the indoor trunk cable 1 passes through through holes in the floor and walls of the building, and moves on a cable rack. However, in the method of the present invention, before the indoor trunk cable is brought in, the Since a protective cover 4 having a tapered surface on the front end side is installed at the above-mentioned branch line connection fitting installation point, the branch line connection fitting etc. can be installed in a through-hole in the floor or wall, a cross member of a cable rack, etc. It can be passed smoothly without getting caught.

In this case, as explained above, if the tapered surface 40a is provided not only at the front end of the protective cover 4 but also at both the front end and the rear end, the protective cover 4
When attaching the cable to the indoor trunk cable 1, there is no directionality between the front and back of the protective cover, which is advantageous in terms of work management, and it is also easy to hook the cable when it becomes necessary to pull it back for some reason during installation. It is effective without causing any

After pulling the main cable into the predetermined route, remove the protective cover 4, connect the branch line connection terminal 21 of the branch line connection fitting 2 to the branch cable,
By insulating the connection part by wrapping it with rubber or plastic tape, the work of laying the indoor trunk cable and connecting the branch cables is completed.

In the above, the protective cover 4 may be attached at the cable installation site before the cable is brought indoors. Further, as shown in FIG. 4, the branch cable 11 can be connected in advance to the branch line connection terminal 21 of the branch line connection fitting 2 in the factory. In this case, the upper and lower pieces of the protective cover 4 It is desirable to fasten with bolts 441 and 442 at the front and rear positions of 21. The branch cable 11 may be two as shown in FIG. 5, and the branch line connection fitting 2 may include a wire as shown in FIGS. 6A and 6B (110 is a conductor of the branch cable). You can use a batch compression method like this. Furthermore, if you connect branch cables in advance in the factory,
As shown in FIG. A, the final insulation treatment 30 of the branch connections can also be performed in advance in the factory.

〔Effect of the invention〕

As described above, in the indoor trunk cable installation method of the present invention, before the indoor trunk cable is brought indoors, a protective cover having a tapered surface on the front end side is attached to the branch line connection fitting attachment part of the cable. Since the cable is routed indoors during installation, when passing through a through-hole in the floor or wall of the building,
Or, when moving on a cable rack, the cable can be pulled in smoothly without getting the branch line connection fittings attached to the cable caught in the through hole, the cross member, or the side member of the rack. Moreover, there is no possibility of injury due to the branch line connecting fitting 2 or the insulating coating layer 3 being caught. The branch line connection fitting 2 is the branch line connection terminal 21
Even if the cable protrudes significantly to the side, it can pass smoothly without getting caught.

Therefore, according to the present invention, at least the process of attaching the branch line connection fitting 2 and the process of applying the insulating coating layer 3 can be performed in advance in the factory. The connection of the branch cable to the branch line connection terminal of the connection fitting, as well as the final insulation treatment of the branch line connection, can be carried out at the factory without fear of being caught or injured during indoor lead-in work. Since the cable can be pre-processed in-house, it has the practical effect of significantly reducing processing at the installation site compared to the conventional method.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an indoor trunk cable that is led indoors by the method of the present invention, FIG. 2 is an enlarged sectional view showing how the branch line connection fitting is attached to the cable conductor in the cross section taken along the line - in FIG. 1, Figure 3A
Also, FIG. 3B is a plan view and side view showing the protective cover used in the present invention, and FIG.
A cross-sectional view taken along the line c-c in Figure A, Figures 4 and 5 are explanatory diagrams showing examples of branch connections of indoor trunk cables brought indoors according to the method of the present invention, and Figure 6A is an explanatory view of the same branch connection. FIG. 6B is an enlarged cross-sectional view taken along the line bb in FIG. 6A and showing how the branch line connecting fitting is attached to the cable conductor. In the figure, 1 is an indoor trunk cable, 2 is a branch line connection fitting, 4 is a protective cover, and 40a, 40b are tapered surfaces.

Claims (1)

[Claims] 1. Processing of removing the insulating layer at a predetermined intermediate portion of the cable and attaching the branch line connecting fitting 2 to the exposed conductor 10, and insulating coating layer 3 for insulating the exposed conductor part and the branch line connecting fitting attachment part. The indoor trunk cable 1 has been processed in advance to provide a A removable protective cover 4 that is divided into upper and lower parts and has a tapered surface 40a at the front end that narrows toward the front.
A method for laying an indoor trunk cable, which comprises the steps of: laying the indoor trunk cable 1, then leading the indoor trunk cable 1 indoors, and removing the protective cover 4 after the indoor trunk cable 1 has been brought indoors. 2. The indoor trunk cable installation method according to claim 1, wherein the protective cover 4 also has a tapered surface 40a on the rear end side, the width of which decreases toward the rear.