JPH1152141A - Optical cable branching and connecting part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prorde an optical cable branching and connecting part capable of easily housing a coated optical fiber connecting part into trays even when tacken-out length of main coated optical fiber from the exposing part of cable cre in a main optical cable is short. SOLUTION: A multipoint optical cable 5 is arranged at the side lower than a main optical cable 1 at the clamping position of a connecting box 8. A surpus length housing tray 15 housing the surpus length part of the branched coated optical fiber 6 taken out from the multipoint optical cable 5 is installed in a direction parallel with exposed cable cores 3 on the connecting box 8. A coated optical fiber connecting part housing tray 17 in which the core connecting par 7 of the main coated optical fiber 4 taken out from the main cable 1 and the branched coated optical fiber 6 is housed is arrranged in an inclined state in the upper part of the surpus housing tray 15 so that one end of the tray 17 goes near the main coated optical fiber 4 taken out form the cable cores 3 at the exposed position of the cable cores 3 and the other end of the tray is nearer to the surpus length housing tray 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure in which a main optical fiber taken out from a cable core in the middle of a main optical cable is connected to a branch optical fiber taken out from an end of a branch optical cable by a fiber connecting portion. And the optical cable branch connection section.

[0002]

2. Description of the Related Art FIGS. 3A and 3B show the structure of a conventional optical cable branch connection section of this type.

In this optical cable branch connection portion, the outer sheath 2 is stripped off over a required length in the middle of the main optical cable 1, and a required main optical core wire 4 is taken out from the exposed cable core 3. The optical fiber 4 is connected to a branch optical fiber 6 taken out from the end of the branch optical cable 5 by a fiber connecting part 7. The exposed portion of the cable core 3 of the main optical cable 1, the cable portions on both sides thereof, and the end of the branch optical cable 5 are gripped by the junction box frame 8. Connection box frame 8
Are main optical cable grippers 10a, 10b standing on both sides of the bottom plate 9 and both ends of the exposed portion of the cable core 3 of the main optical cable 1 and standing on both ends of the bottom plate 9.
And a branch optical cable 5 erected at one end of the bottom plate 9.
And a branch optical cable gripper 11 which grips the end of the optical fiber. A storage tray 12 is arranged on a bottom plate 9 of the connection box frame 8 and supported by a stand 13.

[0004]

In such a conventional optical cable branch connection section, a storage tray 12 for accommodating the core connection section 7 is located at the center of the exposed portion of the cable core 3, and
If the take-out length of the main optical core wire 4 is not sufficient, the core wire connecting portion 7 cannot be stored and fixed in the storage tray 12, and if it is worse, the take-out length of the main optical core wire 4 is short. However, there is a problem that the core wire connecting portion 7 cannot be formed. This problem is caused by the fact that the length of the branch optical cable 6 to be taken out is taken out from the end of the branch optical cable 5 and can be arbitrarily adjusted by setting the stripping length of the jacket 14 of the branch optical cable 5,
The length of the main optical cable 4 to be taken out is determined by the limited exposed length of the cable core 3 of the main optical cable 1 and is cut out at half the length of the exposed cable core to be taken out. In many cases, the length cannot be adjusted arbitrarily.

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical cable branching / connecting portion that can easily store a core connecting portion to a tray even if the length of taking out a main optical core from an exposed portion of a cable core in a main optical cable is short. It is in.

It is another object of the present invention to provide an optical cable branch connection portion capable of receiving vibrations without directly applying vibration to the core connection portions.

Another object of the present invention is to easily store the core connection portion in the tray even if the length of the main optical cable taken out from the exposed portion of the cable core in the main optical cable is short, and the core connection is performed. It is an object of the present invention to provide an optical cable branch connection portion capable of receiving vibration in the core wire connection portion without directly applying vibration to the portion.

[0008]

SUMMARY OF THE INVENTION According to the present invention, a required optical fiber is taken out from an exposed cable core by stripping an outer sheath of the optical cable over a required length in the middle of the main optical cable.
The main optical fiber is connected to the branch optical fiber taken out from the end of the branch optical cable at a core connecting portion, and the exposed portion of the cable core of the main optical cable is connected to the cable portions on both sides thereof and the end of the branch optical cable. An object of the present invention is to improve an optical cable branch connection held by a box frame.

In the present invention, the extra storage tray for storing the extra length of the branched optical fiber is installed on the junction box frame in a direction parallel to the cable core. On the extra length storage tray, there is a core wire connection portion storage tray for storing the core wire connection portion, one end of which is close to the main optical fiber taken out from the cable core at the exposed portion of the cable core, and the other end is left. It is arranged in an inclined state so as to approach the long storage tray.

As described above, the core wire connection portion storage tray is inclined such that one end thereof approaches the main optical core wire extracted from the cable core at the exposed portion of the cable core and the other end approaches the extra length storage tray. When the main optical fiber is taken out from the cable core at the exposed portion of the cable core, the main optical fiber is easily stored in the core connection part storage tray, and the branched optical fiber is disposed. Can also be accommodated.

Further, since the core wire connection portion can be installed at an arbitrary position in the core wire connection portion storage tray, this core wire connection portion storage tray usually requires an optical fiber core required for storing the core wire connection portion. No extra length is required.

In this case, it is preferable that the core wire connection portion storage tray is supported by the extra length storage tray via an elastic support.

In this case, if vibration is applied to the connection box frame, the vibration is directly applied to the extra-length storage tray supported by the connection box frame. Is applied through the elastic support to the core connection portion storage tray supported through the elastic member, the vibration is attenuated by the elastic support, and an excessive force can be prevented from being applied to the core connection. . For this reason, it is possible to prevent adverse effects such as an increase in loss and pop-out on the optical core wire of the core wire connection portion.

[0014]

1 (A), 1 (B) and 2 show a first embodiment of an optical cable branch connection section according to the present invention, and FIGS. 1 (A) (B). FIG. 2 is a side view and a plan view of the optical cable branch connection portion with a case omitted, and FIG. 2 is a perspective view of two trays used in this example.

Also at this optical cable branch connection portion, the outer sheath 2 is stripped off over a required length in the middle of the main optical cable 1, and a required main optical core wire 4 is cut out from the exposed cable core 3 and taken out. ing. The extracted main optical core wire 4 is connected to a branch optical core wire 6 extracted from an end of the branch optical cable 5 by a core wire connection part 7. The core wire connection portion 7 is formed by fusion splicing, but may be formed by other connection methods such as connector connection and mechanical splice connection. Cable core 3 of main optical cable 1
The exposed portion, the cable portions on both sides thereof, and the end of the branch optical cable 5 are gripped by the connection box frame 8. The connection box frame 8 includes a bottom plate 9, and a main optical cable gripper 1 erected on both ends of the bottom plate 9 to grip the cable portions on both sides of the exposed portion of the cable core 3 of the main optical cable 1.
0a, 10b, and a branch optical cable gripper 11 which stands on one end of the bottom plate 9 and grips the end of the branch optical cable 5. These points are the same as in the above-described conventional example.

In the optical cable branch connection section of the present embodiment, the branch optical cable 5 is disposed below the main optical cable 1 at the holding position of the connection box frame 8. The main optical cable 1 is gripped by the main optical cable grippers 10a and 10b, and the branch optical cable 5 is gripped by the branch optical cable gripper 11 so as to maintain the vertical positional relationship.

On the bottom plate 9 of the connection box frame 8, an extra-length storage tray 15 for storing the extra length of the branch optical fiber 6 is installed in a direction parallel to the cable core 3. The extra-length storage tray 15 includes a square bottom plate 15a and a side plate 15b erected on the periphery of the bottom plate 15a.
A core wire entrance / exit 15c is provided at a plurality of locations on the side plate 15b. On the bottom plate 15a of the extra length storage tray 15,
A plurality of column-shaped extra length storage bobbins 16 for winding the extra length of the branched optical core wire 6 are provided upright. The extra length storage tray 15 is fixed on the bottom plate 9 by screws (not shown) or the like. On this extra-length storage tray 15, there is provided a core connection part storage tray 17 for storing the core connection part 7, one end of which is the main optical core 4 taken out from the cable core 3 at the exposed portion of the cable core 3. And the other end is extra length storage tray 1
5 is arranged in an inclined state so as to approach. The core wire connection portion storage tray 17 includes a rectangular bottom plate 17a having a required length, a pair of side plates 17b erected on both edges along the longitudinal direction of the bottom plate 17a, and a pair of these plates. Side plate 17
b, a partition plate 17d which stands on the bottom plate 17a and partitions the inside of the tray 17 into a plurality in the width direction to form a plurality of partition grooves 17c. Both ends in the longitudinal direction of the core wire connection portion storage tray 17, in other words, each partition groove 1
Both ends in the longitudinal direction of 7c are open. Core connection 7
Are housed in the partition groove 17c. Such a core-connection-portion storage tray 17 is supported on the extra-length storage tray 15 via an elastic support 18 made of, for example, a plurality of rubber columns. Each elastic support 18 is arranged so as to support the core connection part storage tray 17 at a different position in the longitudinal direction, and the bottom plate 15a of the extra-length storage tray 15 as a connection partner and the core connection part storage tray. 17 is fixed to the bottom plate 17a. The extra length of the branch optical fiber 6 is wound around the extra length storage bobbin 16 and stored in the extra length storage tray 15.

In such an optical cable branch connection part, the core wire connection part storage tray 17 has one end thereof connected to the cable core 3.
At the exposed position, the cable core 3 is inclined so as to approach the main optical fiber 4 taken out from the cable core 3 and the other end to approach the extra length storage tray 15.
Even if the length of the main optical core wire 4 taken out from the cable core 3 at the exposed portion is short, the core connection portion storage tray 1 can be easily mounted.
7, the core wire connection part 7 with the branch optical core wire 6 can also be housed.

Further, since the core wire connection portion 7 can be installed at any position in the core wire connection portion storage tray 17, the core wire connection portion storage tray 17 is usually required for storing the core wire connection portion 7. The extra length of the main optical fiber 4 is not required.

Further, since the core wire connecting portion storage tray 17 is supported by the extra length storage tray 15 via the elastic support member 18, if vibration is applied to the connection box frame 8, the vibration is generated by the connection box frame 8. The extra storage tray 15 supported by the frame 8 is directly added to the extra storage tray 15.
5 is applied via the elastic support 18 to the core wire connecting portion storage tray 17 supported by the elastic support 18, the vibration is attenuated by the elastic support 18, and Can be prevented from being subjected to excessive force. For this reason, it is possible to prevent adverse effects such as an increase in loss and popping out of the optical core wire of the core wire connecting portion 7.

When the number of the main optical core wires 4 branched and connected at the optical cable branch connection portion is large, the width of the tray 17 is widened to partition the inside of the tray 17. What is necessary is just to increase the number of the partition grooves 17c by increasing the number of the partition plates 17d. Conversely, when the number of main optical fibers 4 branched and connected at the optical cable branch connection portion is small, the partition plate 17d itself can be omitted.

Further, the number of extra length storage bobbins 16 provided in the extra length storage tray 15 is not limited to a plurality but may be one.

Further, in the above example, the branch optical cable 5 is disposed below the main optical cable 1;
May be arranged side by side at the same height as the main optical cable 1.

[0024]

According to the present invention, the core wire connection portion storage tray is
Since one end of the cable core is exposed at the exposed portion of the cable core, and the other end is arranged in an inclined state so as to approach the main optical fiber taken out from the cable core and the other end approaches the extra length storage tray, the exposed portion of the cable core is Even if the length of the main optical fiber taken out of the cable core is short, the main optical fiber can be easily housed in the fiber optical fiber connecting part storage tray and the fiber optical fiber connecting part with the branch optical fiber can also be stored.

Further, since the core connection part can be installed at an arbitrary position in the core connection part storage tray, the optical core required for storing the normal core connection part in this core connection part storage tray is usually used. No extra length is required.

[Brief description of the drawings]

1A and 1B show an example of an embodiment of an optical cable branch connection section according to the present invention.
Is a side view in a state where a case is omitted, and (B) is a plan view.

FIG. 2 is a perspective view of two trays used in this example.

3 (A) and 3 (B) show a conventional optical cable branch connection portion. FIG. 3 (A) is a side view in a case where a case is omitted, and FIG. 3 (B) is a plan view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main optical cable 2 Outer sheath 3 Cable core 4 Main optical core wire 5 Branch optical cable 6 Branch optical core wire 7 Core wire connection part 8 Connection box frame 9 Bottom plate 10a, 10b Main optical cable gripper 11 Branch optical cable gripper 12 Storage tray 13 Stand 14 Sheath 15 Extra length storage tray 15a Bottom plate 15b Side plate 15c Core wire entrance / exit 16 Extra length storage bobbin 17 Core wire connection portion storage tray 17a Bottom plate 17b Side plate 17c Partition groove 17d Partition plate 18 Elastic support

Claims (2)

[Claims] 1. A required main optical fiber is taken out from an exposed cable core in a middle of the main optical cable, and a required length of the main optical fiber is taken out from the exposed end of the branch optical cable. An optical cable that is connected to the branch optical fiber taken out of the main optical cable at a cable connecting portion, and the exposed portion of the cable core of the main optical cable, the cable portions on both sides thereof, and the end of the branch optical cable are gripped by a junction box frame In the branch connection portion, a surplus storage tray for storing the surplus portion of the branch optical core wire is provided on the junction box frame in a direction parallel to the cable core, and the surplus storage tray is provided on the surplus storage tray. A core connection part storage tray for storing the core connection part has one end approaching the main optical core taken out from the cable core at an exposed portion of the cable core and the other end having the extra length storage tray. Optical cable branch connection portion, characterized in that it is arranged in an inclined state so as to approach the. 2. The optical cable branching connection part according to claim 1, wherein the core wire connection part storage tray is supported by the extra length storage tray via an elastic support.