JPS6212314A - Excess length reduction of optical fiber compound overhead ground wire and metal wheel therefor - 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 [Field of Industrial Application] The present invention relates to an improvement in a method for pulling down an optical fiber composite overhead ground wire to obtain extra length necessary for connection.

[Conventional technology and problems] When connecting an optical fiber composite overhead ground wire, the ground wire is tied to the tower using a retaining clamp, and the optical fiber is pulled down along with the extra length of the wire and installed in the middle of the tower. A commonly used method is to guide the optical fibers to a junction box and connect the optical fibers within the junction box.

Conventionally, in order to take out the extra length of the wire, once the wire has been pulled down and extended to the tower, a worker steps onto the wire, attaches a come-along and i-wire at the position where there is extra length, and then removes the wire. The excess length was lowered by pulling the wire, or the wire was loosened to near the ground and the above-mentioned come-along was attached to it.

However, the above-mentioned work for the worker to lean out is an extremely dangerous task, and if the length of pull is long, the work becomes extremely difficult, and the worker may lean onto the ground line, which is relatively small in size. If this occurs, there is a risk that the internal optical fiber may be damaged. Furthermore, the method of letting the wires hang loose on the ground requires conditions such as good terrain and the absence of obstacles, and is not a method that can be implemented everywhere.

[Object of the Invention] The present invention has been made in view of the above-mentioned circumstances, and eliminates the drawbacks of the above-mentioned prior art, and eliminates the dangerous riding on the electric wire and the loosening of the electric wire.
It is an object of the present invention to provide a method for lowering the excess length of an electric wire by which the excess length of the electric wire can be easily taken in, and a metal wheel used for the purpose.

[Summary of the Invention] That is, the gist of the present invention is to suspend a metal wheel having a winding groove capable of wrapping the extra length of the electric wire on a steel tower to be lowered, extend the electric wire via the metal wheel, There is a method of pulling down the extra length by unwinding the wire after that, and a wire wheel with the above-mentioned extra length winding groove formed thereon, thereby making it possible to safely and easily wire the wire by simply winding the wire around the wire wheel and extending the wire. This makes it possible to take extra length.

[Example] This will be explained below based on examples.

FIG. 1 is a front view showing an embodiment of a metal wheel 10 used in carrying out the present invention, in which 1 is a rotating body rotatably attached to a frame 3, and 2 is an outer circumferential surface of the rotating body 1. The winding groove 2 is formed so that the electric wire can be spirally wound in a plurality of turns.

In the present invention, the metal wheel 10 configured as described above is suspended from a steel tower to which the electric wire is to be lowered, and the optical fiber composite overhead ground wire 20 to be extended is suspended from the metal wheel 10 as shown in FIG. The wire is wound around the ten winding grooves 2 and stretched.

Therefore, the length of the winding groove 2 in this case is configured to have a length commensurate with the length of the wire to be pulled down. Now, let this pulling length be L, and the rotating body 1 of the metal wheel 10
When the radius of the spiral circle formed by the full surface of r1 is the number of times the groove is wound as n, there is the following relationship: L=2πr, so this L can be selected to be the above-mentioned pull-down length.

Now, consider an actual railway line that requires the above-mentioned extra length of drawdown of 15 m.

In this case, if the full diameter 2r of the rotating body 1 is selected to be 1 m, it can be seen from the above relational expression that n should be set to approximately 5 times.

Of course, this value changes depending on the pulling length, so it is desirable to have a structure in which the unit groove structures can be connected as appropriate, and the number of windings can be increased or decreased as necessary. FIG. 2 is an explanatory view showing an embodiment of the rotary body 1 suitable for increasing and decreasing the number of grooves, and the length of the groove can be easily changed by forming the winding groove with rollers 4 and increasing and decreasing the number of rollers 4. An example is shown that can be adjusted.

In practical use, the metal wheel according to the present invention configured as described above has two metal wheels arranged in series in the wire running direction, as shown in FIG.
0 and 10, wrap the ground wire 20 around both gold and wheel as shown in the figure and extend the wire, and when the wire extension is completed, cut it at the intermediate point P. By doing this, the left and right spans can be lowered at the same time.

[Effects of the Invention] As described above, according to the pulling down method according to the present invention, there is no need for the worker to stand on top of the electric wire or to unnecessarily loosen the electric wire and pull it down as in the conventional example. This not only greatly improves safety, but also simplifies the work itself, saves labor, and enables efficient lowering.This is a timely solution as the adoption of optical fiber composite overhead ground wires is gaining momentum. The proposal has great industrial significance.

[Brief explanation of drawings]

FIG. 1 is a front view showing an embodiment of the metal wheel according to the present invention, FIG. 2 is an explanatory view showing an example of the structure of the rotating body of the metal wheel according to the present invention, and FIG. FIG. 4 is an explanatory diagram showing one embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Rotating body, 2... Winding groove, 3... Frame body, 10... Metal wheel, 20... Optical fiber composite overhead ground wire. Agent Patent Attorney Fujio Sato% 112] k#J 3rd procedure? City official document (method) FlOllo, 03 Showa year month day 1 case display Showa 60 year patent application No. 147424
No. 2 Name of the invention A method for lowering the extra length of an optical fiber composite overhead ground wire and a metal wheel therefor 3 Relationship with the case of the person making the amendment Patent Name of the applicant (512) Hitachi Cable Co., Ltd. Representative Hiroji Hashimoto 5 Amendment order Date: September 24, 1985 t, :', b XXl 6. Subject of amendment ゛(1)
Drawing Plan 7, Contents of Amendment (1) As shown in the attached sheet. 8. List of attached documents (1) Attachment (drawings) 1 or more copies

Claims (3)

[Claims] (1) A metal wheel with a winding groove capable of wrapping the extra length of the electric wire around the outer periphery of the rotating body is suspended from the steel tower where the excess length of the optical fiber composite overhead ground wire is to be lowered, and the electric wire is attached to the metal wheel. A method for pulling down the extra length of an optical fiber composite overhead ground wire, which involves winding and extending the wire, and then unwinding the extra length of the wire wound around the metal wheel and pulling it down. (2) Two metal wheels with winding grooves that can be used to wrap the extra length of the electric wire around the outer periphery of the rotating body are suspended from the steel tower where the excess length of the optical fiber composite overhead ground wire is to be lowered. Optical fiber composite is produced by continuously winding and extending a wire around two metal wheels, cutting the wire in the middle between the two metal wheels, and then unwinding the excess length of the wire wrapped around the metal wheel and pulling it down. How to lower the extra length of an overhead ground wire. (3) A metal wheel in which a rotating body is supported by a frame body, and a plurality of grooves are formed around the rotating body so that the extra length of the electric wire can be wound therein.