JPH07218733A - Movable excessive-length storage part for optical fiber cable traction end - Google Patents

Abstract

PURPOSE:To provide the movable excessive-length storage part for the optical fiber cable traction end which can store the movable excessive-length part of the optical fiber cable traction end in a fixed state in a closure for optical fiber cable connection and is easily handled and operated. CONSTITUTION:In a box 11 provided inside the cable lead-out opening of the closure 1, a couple of cylindrical members 12 and 13 whose radius is larger than the radius of curvature of an optical fiber cable 2 are arranged in the extension direction of the optical fiber cable 2 relatively movably in radius directions, the movable excessive-length part 2a of the optical fiber cable 2 inserted into the closure 1 is wound around the cylindrical member 13 at a distance from the cable lead-out opening and also wound reversely around the cylindrical member 12 nearby the cable lead-out opening, and while this optical fiber cable 12 is connected to another optical cable, the cylindrical members 12 and 13 are separated in the radius directions to hold the movable excessive length part 2a without a slack.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for pulling and laying an optical fiber cable, and stores an optical fiber cable with a movable extra length fixed at the optical fiber cable pulling end in a closure for connecting the optical fiber cable. The present invention relates to a movable extra length storage portion at a fiber cable pulling end.

[0002]

2. Description of the Related Art Conventionally, when a plurality of optical fiber cable pulling ends are connected to each other in an optical fiber cable connecting closure, a movable extra length storing portion is provided inside one optical fiber cable outlet of the closure. The movable extra length is stored in the movable extra length storage portion in a state in which the movable extra length generated at the pulling end of the optical fiber cable is wound in a loop shape. The movable extra length storage portion is, for example, a shelf-shaped one in which thin plates made of hard plastic or the like are arranged at predetermined intervals in the thickness direction, and the three directions around these thin plates are surrounded by thin plates of the same quality. There is.

[0003]

By the way, in the conventional movable extra length storing portion at the pulling end of the optical fiber cable, since the movable extra length is stored in a state of being wound in a loop shape, the movable extra length is stored due to vibration or the like. There is a drawback that the loop-shaped portion is easily moved and the radius of the loop is changed. When the radius of the loop becomes equal to or smaller than the radius of curvature of the optical fiber, the optical signal propagating in the fiber leaks and the optical signal is attenuated. Therefore, it is necessary to keep the radius of the loop portion at the radius of curvature of the optical fiber or more. Therefore, a method of storing the loop-shaped optical fiber after tying it with a string or the like can be considered, but it has a drawback that it takes time to tie the optical fiber and the shape of the loop is difficult to be constant.

The present invention has been made in view of the above circumstances, and can be stored in a state in which the movable extra length of the pulling end of the optical fiber cable is fixed in the optical fiber cable connecting closure, and the handling is possible. It is an object of the present invention to provide a movable extra length storage portion for the pulling end of an optical fiber cable which is simple and easy to work.

[0005]

In order to solve the above-mentioned problems, the present invention employs the following movable extra length storing portion of the pulling end of the optical fiber cable. That is, a storage unit that stores a movable extra length of the optical fiber cable pulling end used when connecting the plurality of optical fiber cable pulling ends in the optical fiber cable connecting closure, and one optical fiber of the closure. A pair of cylindrical members whose radius is larger than the radius of curvature of the optical fiber can be moved in the box provided inside the cable outlet in the radial direction relative to each other along the extending direction of the optical fiber cable. And the movable extra length of the optical fiber cable inserted into the closure from the optical fiber cable drawing port is wound around the cylindrical member on the side separated from the optical fiber cable drawing port, and the optical fiber cable drawing is performed. The optical fiber cable is wound around the cylindrical member close to the outlet in the direction opposite to the winding direction, and the pulling end of this optical fiber cable is connected to the other optical fiber. While connected with the traction end of the cable, it is characterized in that mutually separate from each other these cylindrical members in the radial direction is held against slackening the movable excess length.

[0006]

In the movable extra length storing portion of the optical fiber cable pulling end according to the present invention, the movable extra length of the optical fiber cable inserted into the closure from the optical fiber cable pulling port is separated from the optical fiber cable pulling port. It is wound around a side (far side) cylindrical member, and is wound around the side (closer side) cylindrical member close to the optical fiber cable insertion port in a direction opposite to the winding direction. Then, the pulling end of this optical fiber cable is connected to the pulling end of the other optical fiber cable, and while maintaining this connected state, these cylindrical members are separated from each other in the radial direction without loosening the movable extra length. To hold.

As described above, by winding the movable extra length of the optical fiber cable around the two cylindrical members in an S-shape,
The movable extra length is housed in a wound state with a radius larger than the radius of curvature of the optical fiber cable. Therefore,
Even if vibration or the like is applied, there is no fear that the radius of the wound portion of the movable extra length will change, the optical signal propagating in the optical fiber will not leak, and the attenuation of the optical signal will be suppressed. . Further, after the movable extra length is wound around the cylindrical member, it is only necessary to separate the cylindrical members from each other in the radial direction, so that the handling becomes easy and the workability is improved. In addition, it is possible to handle various movable lengths with only one type of movable length storage unit, thus improving workability and productivity.

[0008]

1 is a perspective view showing a closure provided with a movable extra length storing portion at an end of an optical fiber cable according to an embodiment of the present invention. In FIG. 1, 1 is a closure for connecting an optical fiber cable. 2 is an optical fiber cable in which a plurality of optical fibers are bundled, and 3 to 5 are optical communication cables in which the optical fiber cables 2, 2, ...
Reference numerals 6a and 6b denote connectors provided at the pulling end of the optical fiber cable 2, and reference numeral 7 denotes a movable extra length storing portion for storing the movable extra length 2a of the pulling end of the optical fiber cable 2. The closure 1 is provided with five movable extra length storage portions 7 along the arrangement direction of the optical fiber cables 2, 2, ....

As shown in FIG. 2, the movable extra length storage portion 7 is provided inside the outlet of one optical communication cable 3 of the closure 1 and is provided with the optical fiber cable 2.
A flat box 11 provided along the arrangement direction of the flat box 11 and the flat box 11
It is composed of a pair of reels (cylindrical members) 12 and 13 arranged along the extending direction of the optical fiber cable 2. The flat box 11 is a flat box shape made of transparent plastic or the like, and has a lid 14 that can be opened and closed on the front side (direction perpendicular to the paper surface in FIG. 2) and is provided on both side surfaces in the longitudinal direction. Openings 15 and 16 are formed at the ends so as not to face each other.

The reel 12 (13) has a groove 17 for inserting the optical fiber cable 2 formed on the outer peripheral surface of a disk made of plastic or the like, the radius of which is larger than the radius of curvature of the optical fiber cable 2. Is. Here, the reel 12 is fixed in position by a shaft 18 in the vicinity of one end of the flat box 11, and is rotatable about the shaft 18.
Further, the reel 13 is provided with a shaft 18 near the other end of the flat box 11.
The reel 12 can be separated from or close to the reel 12, can be fixed at a predetermined position, and can be rotated around the shaft 18.

In the movable extra length storage portion 7, the movable extra length 2 of the optical fiber cable 2 inserted from the opening 15 is provided.
"a" is wound around the groove 17 of the reel 13 and is wound around the groove 17 of the reel 12 in the direction opposite to the winding direction of the reel 13, and has an S-shape as a whole. And
The tip of this optical fiber cable 2 is pulled out from the opening 16 and is connected to the other optical fiber cable 2 by the connectors 6a and 6b. The reel 13 is fixed in a state of being moved so as to be separated from each other in the radial direction with respect to the reel 12 so that the movable extra length 2a does not loosen.

In order to store the optical fiber cable 2 in the movable surplus length storing portion 7, the reel 13 is brought close to the reel 12 in advance, the end portion of the optical fiber cable 2 is inserted from the opening portion 15, and the movable portion is moved. The extra length 2a is set in the groove 17 of the reel 13.
And then reel 1 so that the whole is S-shaped.
The reel 17 is wound around the second groove 17 in a direction opposite to the winding direction of the reel 13. Next, the tip of the optical fiber cable 2 is pulled out from the opening 16 and connected to the other optical fiber cable 2 via the connectors 6a and 6b. Next, the reel 13 is moved so as to be separated from the reel 12 in the radial direction, the movable extra length 2a is held so as not to be loosened, and the reel 13 is fixed.

In this way, the movable extra length 2a of the optical fiber cable 2 is wound around the reels 12 and 13 in an S-shape, and the reels 12 and 13 are separated from each other, so that the movable extra length 2a is provided to the optical fiber. It is possible to store the cable 2 in a wound state with a radius larger than the radius of curvature of the cable 2.

As described above, according to the movable extra length storage portion of the optical fiber cable pulling end of the above-described embodiment, the movable extra length 2a of the optical fiber cable 2 is wound around the reel 13 and the reel 12 is provided with the above-mentioned movable extra length 2a. Since the reel 13 is wound in a direction opposite to the winding direction and the reel 13 is moved and fixed so as to be separated from each other in the radial direction with respect to the reel 12 so that the movable extra length 2a is not loosened, the movable extra length 2a is fixed. Can be stored in a wound state with a radius larger than the radius of curvature of the optical fiber cable 2, and the radius of the wound portion of the movable extra length 2a changes when vibration or the like is applied. Can be prevented, leakage of the optical signal propagating in the optical fiber can be prevented, and attenuation of the optical signal can be suppressed.

The movable length is set to the reels 12, 1
Since the reels 12 and 13 only have to be separated from each other in the radial direction after being wound around 3, the handling becomes easy and the workability can be improved. Further, it is possible to cope with the movable extra lengths 2a of various lengths by using only one type of the movable extra length storage section 7, so that the workability and the productivity can be improved.

[0016]

As described above, according to the movable surplus length storing portion of the optical fiber cable pulling end of the present invention, the radius is provided in the box provided inside one of the optical fiber cable pulling outlets of the closure. A pair of cylindrical members having a radius of curvature larger than that of the optical fiber are arranged so as to be movable relative to each other in the radial direction along the extending direction of the optical fiber cable,
The movable extra length of the optical fiber cable inserted into the closure from the optical fiber cable outlet is wound around a cylindrical member on the side away from the optical fiber cable outlet and is close to the optical fiber cable outlet. The cylindrical member on the side is wound in the opposite direction to the winding direction, and the cylindrical members are separated from each other in the radial direction with the pulling end of the optical fiber cable connected to the pulling end of the other optical fiber cable. Since the movable extra length is held so as not to sag, the movable extra length can be stored in a state of being wound with a radius larger than the radius of curvature of the optical fiber cable, and the movable extra length can be stored when vibration or the like is applied. It is possible to prevent the radius of the wound portion of the extra length from changing, and prevent leakage of the optical signal propagating in the optical fiber.
It is possible to suppress the attenuation of the optical signal.

Further, after the movable extra length is wound around the cylindrical member, it is only necessary to separate these cylindrical members from each other in the radial direction, so that the handling becomes easy and the workability can be improved. Further, only one type of movable extra length storage section can accommodate various movable extra lengths, and therefore workability and productivity can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a closure having a movable extra length storage portion at a pulling end of an optical fiber cable according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view showing a movable extra length storage portion at a pulling end of an optical fiber cable according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Closure for optical fiber cable connection, 2 ... Optical fiber cable, 2a ... Movable extra length, 3-5 ... Optical communication cables, 6a, 6b ... Connector, 7 ... Movable extra length storage part,
11 ... Flat box, 12, 13 ... Reel (cylindrical member), 14
... Lid, 15, 16 ... Opening, 17 ... Groove, 18 ... Shaft.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuto Matsumoto 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation

Claims (1)

[Claims] 1. An accommodating portion for accommodating a movable extra length of an optical fiber cable pulling end used when connecting the optical fiber cable pulling ends in the optical fiber cable connecting closure, wherein one light of the closure is used. Inside the box provided inside the fiber cable outlet, a pair of cylindrical members whose radius is larger than the radius of curvature of the optical fiber are moved relative to each other in the radial direction along the extending direction of the optical fiber cable. The movable extra length of the optical fiber cable inserted into the closure through the optical fiber cable outlet is wound around a cylindrical member on the side separated from the optical fiber cable outlet, and the optical fiber cable is also provided. The optical fiber cable is wound in a direction opposite to the winding direction on a cylindrical member close to the outlet, and the pulling end of this optical fiber cable is connected to the other optical fiber. While connected with the traction end of Buru, movable excess length storage section of the cable pulling end, wherein the holding is separated from each other these cylindrical members in the radial direction so as not to sag said movable excess length.