JPS6114605A - Method for drawing out optical fiber cable - Google Patents

Abstract

PURPOSE:To give no damage to a cable at the time of drawing out by drawing an optical fiber cable contained in an overhead ground wire by engaging it with an endless driving belt of a receiving device having a buffer layer provided with a guide groove, and drawing it out of the inside of the overhead ground wire. CONSTITUTION:A receiving device 5 of a shoe chain system is provided with a cylindrical drum body 18 rotated by a driving source 17, many guide rollers 19 which are holding a prescribed gap on the outside peripheral surface of this body 18 and have been provided in the shape of a semicircular are as a whole, and an endless driving belt 6 consisting of many connected caterpiller blocks, etc. wound around spirally so as to extend over the outside peripheral surface of these guide rollers 19 and the drum body 18. Also, a groove 6a whose section is a U-shape is formed on the upper face of this driving belt 6, a buffer material such as synthetic rubber, etc. is stuck to a prescribed thickness on the surface of the driving belt 6 and a buffer layer 4 is formed, and a guide groove 3 for engaging an optical fiber cable, of the same as the groove 6a is formed on the surface of said layer 4.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a method for pulling out an optical fiber cable under equal pressure when replacing an optical fiber cable installed in an overhead ground wire with a new optical fiber cable. .

[Conventional technology and its problems]

In recent years, an optical fiber composite overhead ground line has been constructed by incorporating an optical fiber cable as a signal transmission cable into an overhead ground line.

Figure 3 shows an example of an optical fiber composite overhead ground wire.
This optical fiber composite overhead ground wire is constructed by providing a pipe made of aluminum or the like in the center of the overhead ground wire consisting of a metal twisted wire layer 6, and
It has a structure in which the internal pressure optical fiber cable 2 is inserted through the hollow [7].

As shown in FIG. 4, the optical fiber composite overhead ground wire is held down by support towers 8a and 8b such as steel towers and is installed along the upper part of the power transmission line 9... The cable 2 is pulled out from the end of the metal stranded wire layer 6 constituting the overhead ground wire 1 near the retaining portion of the overhead ground wire 1 and installed near the tops of the support towers 8a and 8b. They are each introduced into the connector 10 and optically connected therein.

By the way, the optical fiber cable 2 in the overhead ground wire 1 installed between the support towers 8a and 8b in this way will
It must be pulled out from within the overhead ground wire 1 in order to replace it with the required new optical fiber cable.

The conventional method for pulling out and pulling in optical fiber cables in such a case will be explained based on FIG. 5. First, the support towers 8a + 8 on both sides of the span to be replaced
Both ends 2a of the existing optical fiber cable 2 accommodate the internal pressure of the overhead ground wire 1 at b.

2b is removed from the optical fiber cable splicer 10, installed on the sending drum 12' formed by winding a new replacement optical fiber cable 11 on the ground near one of the support towers 8b, and On the ground near the support tower 8a side, there is a winder 14 having a drum-shaped winding capstan 13 and a pulled optical fiber cable 2.
A winding drum 15 for winding ft is installed.

Next, the tip of the new optical fiber cable 11 for replacement is pulled up along the support tower 8blC and connected to the end 2b of the existing optical fiber cable 2 to be pulled out, while on the support tower 8 & side, the tip of the existing optical fiber cable 2 to be pulled out is pulled up. A pulling wire 16 is connected to the end 21L of the optical fiber bundle 2, and the pulling wire 16 is wound several times around the winding capstan 13 of the winding machine 14, and then connected to the winding drum 15.

Next, the winder 14 is operated to pull out the optical fiber cable 2 from within the overhead ground wire l and wind it onto the winding drum 15, while the other end 2b of the optical fiber cable 2 The above-mentioned new optical fiber cable 11 for replacement, which is connected to .

However, in the conventional method for pulling out the optical fiber cable 2, the winding machine 14 uses the winding carburetor 13 as shown in FIG. Since the winder 14 uses a drum-shaped drum, the optical fiber cable 2 twists and rotates on the outer peripheral surface of the drum-shaped Φ cast 13 from both sides toward the center during winding. This makes it easy for the optical fiber cable to slide sideways, which may cause the optical unit to lose its shape or, in the worst case, cause the optical fiber core to break, making it impossible to reuse the expensive optical fiber cable 2. It was a book that caused a huge financial loss.

[Purpose of the invention]

This invention was made in view of the above circumstances, and an object of the present invention is to provide a method for pulling out an optical fiber cable, which does not cause damage to the optical fiber cable when it is pulled out, and can therefore reliably reuse the cable. That is.

[Structure of the invention]

The method for pulling out an optical fiber cable of the present invention involves pulling an existing optical fiber cable to be pulled out from within an overhead ground wire while engaging with an endless drive band of a pulling device having a buffer layer with a guide groove. This is what I did.

[Example] Figures 1 (G), (I3), (C'l) and Figure 2 are books showing an example of a collection device used when carrying out the method of the present invention, and this collection device 5 is This is a so-called shoe chain system, and consists of a cylindrical drum body 18 rotated by a drive source 17, and a semi-circular arc shape as a whole, with llf held at a predetermined distance from the outer peripheral surface of the drum body 18. It has a large number of guide rollers 19, and an endless drive band 6 consisting of a large number of connected caterpillar blocks, etc., wound spirally so as to straddle the outer peripheral surface of these guide rollers 19 and the drum body 8. As shown in FIG. 2, a groove 6a with an H-shaped cross section is formed on the upper surface of the endless drive band 6.
Furthermore, a buffer layer 4 is formed by pasting a highly elastic buffer material such as synthetic rubber to a predetermined thickness on the surface of the endless drive band 6, and the surface of the buffer layer 4 has grooves of the same shape as the grooves 6a. A guide $3 for holding the optical fiber cable is formed.

Therefore, in a method for pulling out the optical fiber cable 2 using such a pulling device 5, as shown in FIG. g15, engages with the guide groove 3 of the buffer layer 4 on the upper surface of the endless drive band 6 as shown in FIG. It is fixed to the drum 15. Then, by driving the take-up device 5, the drum main body 18 is rotated and moved along the inner groove 3, and is sequentially taken up on the take-up drum 15. Therefore, the above optical fiber cable 2
This eliminates the side-sliding and twisting that occurs when taking up the winding capstan using a conventional drum-shaped take-up capstan, and the pressure force in the radial direction is alleviated. This eliminates the risk of the optical fiber becoming deformed or the optical fiber core breaking.

In the above embodiments, a so-called shoe chain type pulling device 5 is shown, but the present invention is not limited to this. For example, a caterpillar type pulling device having a guide groove formed on the outer peripheral surface and a curved buffer layer may be used. It may be.

〔Effect of the invention〕

As explained above, according to the present invention, when pulling out the entire optical fiber cable from the overhead ground wire, a pulling device having an endless drive band is used, and the optical fiber cable is pulled out from the buffer layer on the upper surface of the endless drive band. Since the optical fiber cable is pulled while engaging with the guide groove of the optical fiber cable, the optical fiber cable no longer experiences sideways movement or twisting rotation as in the conventional case.
[The pressure contact force against the above-mentioned buffer layer is reduced, and as a result, the optical fiber cable can be pulled out without the risk of deforming the unit, damaging the center wire, etc., and reducing the cost. This makes it possible to reuse optical fiber cables.

[Brief explanation of the drawing]

Layer N1JG (81, (C) to FIG. 2 show an embodiment of a pulling device used when carrying out the optical fiber cable pulling method of the present invention.
Figure (A) is a front view, 0 is a side view, (Q is a plan view, Figure 2 is a schematic cross-sectional view of the endless drive belt, Figure 3 is a schematic cross-sectional view showing the original fiber mating overhead ground wire) Fig. 4 is a schematic diagram showing the installation state of the original fiber composite overhead ground wire and a detailed explanation of the present invention, and Fig. 5 (A). It is a schematic diagram. l... Overhead ground wire, 2... Original fiber cable, 3... Guide M14... Buffer layer, 5... Pulling device, 6... Endless drive band.

Claims (1)

[Claims] The optical fiber cable (2) housed in the overhead ground wire (1) is engaged with an endless drive band (6) of a pulling device (5) having a buffer layer (4) with a guide groove (3). A method for pulling out an optical fiber cable, the method comprising pulling it out from within an overhead ground wire (1) by pulling the cable while pulling the cable.