JPH0352041B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to a processing device for excess length in a line distribution device for optical fiber cables used in optical communication systems.

(b) Background of the technology Optical communication systems have the characteristic of being able to transmit and receive signals such as large-capacity calls and video signals compared to conventional systems.
Optical fiber cables cannot be arbitrarily cut and connected like copper wire cables because of the amount of man-hours, equipment, and
There are many restrictions due to technology, etc., and in order to connect equipment racks, it is necessary to determine an appropriate length in advance and connect connecting parts such as optical connectors.

(c) Prior art and problems Figure 1 is a block diagram showing the connection of two terminal stations. An optical fiber cable 4 is installed between the station building 1 and the station building 2 through an underground manhole 3, but the optical fiber cable 4 rising from the underground is temporarily installed in the line distribution device (LDF: Line
The data enters the Distribution Frame 5 and is distributed to the equipment racks 6 of the station buildings 1 and 2. However, depending on the arrangement, the length of the optical fiber cable 7 in the station buildings 1 and 2 differs depending on the arrangement position of each equipment rack 6. Sometimes this distance reaches 100 meters inside the station building. In this case, cutting or welding (splicing) the optical fiber cable 7 according to the position of each equipment rack 6 is extremely complicated work, so generally the line distribution device 5 accommodates the excess length and The length of the long optical fiber cable 7 is used. Therefore, it is necessary to adjust the extra length by about 3 to 5 m.

FIG. 2 is a perspective view showing the relationship between the line distribution device and the equipment rack. The equipment rack 6 and the line distribution device 5 are connected by an optical fiber cable 7, and the extra length 8 of the optical fiber cable 7 is housed inside the line distribution device 5 in the form of a loop.

FIG. 3 is a perspective view showing a conventional structure for accommodating an extra length of optical fiber cable inside a line distribution device. An optical fiber cable 7 with a diameter of about 30 cm is wound around a large number of guide rods 52 on an iron frame 51 in a line distribution device 5, and the upper part 7a of the optical fiber cable 7 is guided to the equipment rack 6, and the lower part 7b is guided to the manhole 3. It's dark. This loop-shaped optical fiber cable loop 7c has a large number of loops stacked one on top of the other, and is further arranged in a large number of groups as shown in the figure.

This method is simple, requires less storage space, and is economical; however, it is difficult to change the length of the optical fiber cable, such as when changing the arrangement of the equipment rack 5 due to a sudden increase in the number of subscribers, or when removing and moving the equipment. It is necessary to sequentially unravel the large number of loop-shaped optical fiber cables 7 and replace the accommodation of each optical fiber cable 7, which is an extremely complicated work.

FIG. 4 is a perspective view showing another structure for accommodating the extra length of the optical fiber cable. In order to accommodate the optical fiber cable 7 vertically, cable holders 11 are arranged and fixed in a complex manner on the circumference. The cable holder 11 is provided with a resilient tongue 11a, and the loop 70 of the optical fiber cable 7 is pushed through the opening 11b of the tongue 11a. In this method, too, a large number of loops are stacked and pushed in, so it is complicated to take out the intermediate loops, as in the structure shown in FIG. 3 described above. Furthermore, in the case of optical fiber cables, care must be taken when handling them since transmission characteristics change due to unreasonable tension applied to the cables.

All of the above have economical effects when the optical communication system is fixed, but it becomes a drawback when the system is changed once.

(d) Object of the Invention The present invention enables individual insertion and removal of the above-mentioned portion of the optical fiber cable that accommodates the extra length.

(e) Structure of the Invention The present invention uses a movable board that winds the extra length of an optical fiber cable due to a difference in the arrangement position of equipment racks onto a rotating disk reel and rotatably supports the disk reel in an optical communication system. Furthermore, the optical fiber cable is rotatably mounted on a device rack, and the optical fiber cable can be freely wound up and unwound by rotating the disc reel when the movable plate is rotated and pulled out from the arrangement position of the movable plate. The above object is achieved by the surplus length processing device.

(f) Embodiment of the Invention FIG. 5 is a perspective view of the basic structure for processing the excess length of an optical fiber cable according to the present invention. For the sake of explanation, two structures are shown side by side for simplicity. It actually consists of many columns. A disk reel 21 having a diameter of about 20 cm is supported by a shaft 22 on the movable plate 20 and is rotatable. There are four cutouts 21 on the disc reel 21.
a is formed, and the groove 2 of this cut-and-raised 21a
In the figure, the optical fiber cable 7 is bundled into two bundles and wound around 1b in a loop shape.

The movable platen 20 is rotatably supported on the equipment rack 5 by a shaft 23 at a lower front corner. The movable board 20 can be turned by hand in the direction of arrow A.
The movement plan 20' shows the state in which 20 is rotated by 90 degrees.
In this case, since the disc reel 21 is rotatable, it is pulled by the optical fiber cable 72 fixed to the equipment rack 5 and rotates freely, so that the optical fiber cable 71 is sent out.

Now, when it is desired to appropriately dispose of the excess length of the optical fiber cable 7 in the line distribution device 5, for example, when pulling out the optical fiber cable 72, the disk reel 21' may be rotated and pulled out in the state of the movable board 20'; The optical fiber cable 73 may be cut up and removed from the 21a, or the excess optical fiber cable 7 may be wound onto the disk reel 21'. In any case, the insertion and removal of the extra length of optical fiber cable 7 is completed in this state. When the work is completed, the disk reel 21' is rotated by hand again, and at the same time, the movable plate 20' is pulled up in the direction of arrow B, rotated 90 degrees, and returned to the initial state of the movable plate 20.

FIG. 6 is a perspective view of an optical cable surplus length processing structure according to the present invention. The basic structure explained in FIG. 5 is made into double rows, and is used as an accommodation structure in a line distribution device. Optical fiber cable 73 from manhole 3
is wound into a band shape onto each disk reel 21, and then distributed to the equipment rack 5.

In the embodiment of the present invention, the movable plates are arranged vertically in accordance with the structure of a conventional line distribution device, but the movable plates are not particularly limited to being vertically arranged, and can also be arranged horizontally. Furthermore, since the position of the rotating shaft of the movable board is determined by the position of the optical fiber cable fixed to the line distribution device, it is not limited to the lower front, but may be the upper front.

(g) Effects of the Invention According to the present invention, the length of the optical fiber cable is determined according to the arrangement position of the equipment rack, and the remaining length is wound up on a disc reel in an orderly manner, thereby preventing undue tension from being applied to the optical fiber cable. cable length can be changed at any time as needed.
At this time, it becomes possible to process them individually. As a result, it becomes easy to change the optical communication system, and the system as a whole can be made more economical. For example, it is easy to move and distribute equipment racks. In addition, structurally, the accommodating efficiency within the line distribution device is high, and there is little fear of tangling with optical fiber cables.

[Brief explanation of drawings]

Figure 1 is a configuration diagram showing the connection of two terminal stations, Figure 2 is a perspective view showing the relationship between the line distribution equipment and the equipment rack, and Figure 3 is the extra length of the optical fiber cable inside the line distribution equipment. FIG. 4 is a perspective view showing another optical fiber cable surplus length storage structure; FIG. 5 is a perspective view of the basic structure for handling the optical fiber cable surplus length according to the present invention; FIG. 6
The figure is a perspective view of an optical cable surplus length processing structure according to the present invention. In the figure, 1 and 2 are station buildings, 3 is a manhole, and 5
1 is a line distribution device, 6 is a device rack, 7 is an optical fiber cable, 20, 20' is a movable board, and 21, 21' is a disc reel.

Claims (1)

[Claims] 1. A disk reel for winding the extra length of an optical fiber cable, a movable plate that rotatably supports the disk reel,
an equipment rack on which the movable plate is arranged with the mounting surface of the disc reel being vertical; the movable plate is pivotally supported by the equipment rack at its lower end on the front side, and the lower end on the front side is a fulcrum. An optical fiber cable surplus length processing device, characterized in that the disc reel can be pulled out by rotating the movable plate.