JP2000075160A - Optical cable branching/coupling part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably support respective coated optical fiber coupling parts. SOLUTION: A middle part of a required main coated optical fiber 6 in a cable core 3 exposed from a main optical cable 1 is cut off, and end parts of branch coated optical fibers 7, 8 of respective branch optical cables 4, 5 are coupled respectively to respective cut end parts of this main coated optical fiber 6 with coated optical fiber coupling parts 9, 10. The cable parts 1A, 1B of both sides of the exposed part of the cable core 3 and the end parts of respective branch optical cables 4, 5 are held by a coupling box frame 11. An excess length tray 13 housing the excess length parts 7a, 8a of respective coated optical fibers 7, 8 is set upon the coupling box frame 11. Two sets of coated optical fiber coupling part housing trays 14, 15 are arranged respectively on the excess length housing tray 13 in the tilted state so that their respective one ends come close to both ends of the exposed part of the cable core 3, and the other ends come close to the excess length housing tray 13. Respective coated optical fiber coupling parts 9, 10 are supported respectively onto respective coated optical fiber coupling part housing trays 14, 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 As one type of optical cable branch connection section, as shown in FIG. 3, an outer jacket 2 is stripped over a required length in the middle of a main optical cable 1 to expose a cable core 3, and a cable core 3 is exposed. Each end of the branch optical cables 4 and 5 is disposed adjacent to both ends of the exposed portion of the optical fiber 3, and a required main optical core 6 in the exposed cable core 3 is provided.
Are cut off, and the ends of the branch optical fibers 7, 8 taken out from the ends of the branch optical cables 4, 5 are respectively connected to the cut ends of the main optical core 6, and the core connecting portions 9, 10, the cable portions 1A and 1B on both sides of the exposed portion of the cable core 3 of the main optical cable 1 and the respective branch optical cables 4 and 5
Has a structure in which the end of the frame is held by the connection box frame 11. That is, in the middle of the main optical cable 1, a required main optical core 6 is taken out from the cable core 3 whose outer sheath 2 has been stripped off over a required length and exposed, and an intermediate portion of the main optical core 6 is taken out. And the ends of the split optical fibers 7, 8 taken out from the ends of the split optical cables 4, 5 are connected to the cut ends of the cut main optical fiber 6 at the core connection portions 9, 10, respectively. There is an optical cable branch connection part of a connection type.

[0003]

In such a type of optical cable branch connection, the required main optical fiber 6 in the exposed cable core 3 is connected at an intermediate portion thereof.
Unlike the case where the required main optical core wire 6 is cut off at one end of the exposed cable core 3, the length of each of the cut main optical core wires 6 is shortened, so that the core is cut off. It is difficult to lower the wire connection portions 9 and 10 with a margin below the junction box frame 11, and each of the core wire connection portions 9 and 1 is difficult to lower.
0 cannot be stably supported below the inside of the connection box frame 11, and each of the core wire connection portions 9 and 10 is in an unstable support state, and causes vibrations independently due to external vibrations and the like, resulting in transmission loss. There was a problem that it increased or lead to fatigue cutting of the cord.

[0004] It is an object of the present invention to provide an optical cable branch connection portion capable of stably supporting each of the optical fiber connection portions.

It is another object of the present invention to provide an optical cable branch connection portion in which external vibration is hardly transmitted to each core wire connection portion.

[0006]

According to the present invention, a cable core is exposed in the middle of a main optical cable by stripping its outer surface over a required length, and the cable core is exposed adjacent to both ends of the exposed portion of the cable core. Then, each end of the branch optical cable is disposed, and the intermediate portion of the required main optical core in the exposed cable core is cut, and the cut end of the main optical core is connected to the end of each branch optical cable. The ends of the branched optical cables respectively taken out from the sections are connected at the cable connecting portions, and the cable portions on both sides of the exposed portion of the cable core of the main optical cable and the ends of the respective branched optical cables are gripped by the junction box frame. The present invention is to improve the existing optical cable branch connection section.

[0007] In the optical cable branch connection section according to the present invention, a surplus storage tray for storing the surplus portion of each branch optical core wire is installed on the junction box frame in a direction parallel to the cable core. On the extra-length storage tray, two sets of core wire connection portion storage trays are arranged in an inclined state such that one end of each of them approaches the exposed end of the cable core and the other end approaches the extra-length storage tray. Have been. Each core connection part is supported on each core connection part storage tray. On the extra length storage tray, extra length portions of the respective branched optical fibers are stored.

[0008] When the two sets of core wire connection part storage trays are respectively arranged in an inclined state on the extra length storage tray, the required main optical core of the exposed cable core of the main optical cable is located between the two. Even if the length is short at the portion, the respective core connection portions connected thereto can be stably supported on the inclined core connection portion storage tray. For this reason, each core wire connection part is in an unstable supporting state as in the conventional case, and causes vibration alone due to external vibration or the like, which increases transmission loss or leads to fatigue cutting of the core wire. Can be prevented.

In this case, it is preferable that each of the cord connecting portion storage trays is supported by the extra length storage tray via an elastic support. With such a structure, it is difficult for external vibrations to be transmitted from the connection box frame side to each of the core connection part storage trays, and each core connection part can be protected from external vibration.

[0010]

1 (A), 1 (B) and 2 show an example of an embodiment of an optical cable branch connection section according to the present invention. FIG. 1 (A) shows an optical cable branch of this example. FIG. 2B is a side view of the connection portion, FIG. 2B is a plan view of the optical cable branch connection portion shown in FIG. 2A, and FIG. 2 is a perspective view showing a main configuration of the optical cable branch connection portion of this example.

In the optical cable branch connection section of this embodiment,
On the connection box frame 11, an extra-length storage tray 13 that accommodates the extra-length portions 7 a, 8 a of the respective branch optical cores 7, 8 via a support base 12 is installed in a direction parallel to the cable core 3. The extra-length storage tray 13 is provided with inlets 13a and 13b for introducing the respective branched optical cores 7 and 8. On the extra-length storage tray 13, each of the core wire connection portions 9, 10
Of the core wire connection portion storage trays 14 and 15 are arranged in an inclined state such that one end thereof approaches the both ends of the exposed portion of the cable core 3 and the other end approaches the extra length storage tray 13. ing. These core connection section storage tray 1
4 and 15 are elastic supports 16 and 17 such as rubber, respectively.
And is supported by the extra-length storage tray 13 via the. Each of the core wire connection portions 9 and 10 is provided with the core wire connection portion storage tray 14,
15 respectively. Extra storage tray 13
The extra lengths 7a and 8a of the respective branched optical cores 7 and 8 are accommodated above. A pair of core guides 18a, 1a is provided so that these extra lengths 7a, 8a can be stored on the extra length storage tray 13 without being smaller than the allowable bending radius.
8b are arranged.

The junction box frame 11 is provided with clamps 19a, 19b, 20a, and 20b on both ends of the cable portions 1A and 1B and the ends of the branch optical cables 4 and 5 on both sides of the exposed portion of the cable core 3 of the main optical cable 1. Respectively.

In the case of this embodiment, partitioning bodies 21a and 21b are respectively provided on the core wire connecting part storage trays 14 and 15 so that the plural core wire connecting parts 9 and 10 on each side can be individually stored. ing.

Although not shown in the drawing, the optical cable branch connection portion is provided with a case which is liquid-tight after the connection operation to protect the inside.

When the two sets of core wire connection part storage trays 14 and 15 are respectively arranged on the extra length storage tray 13 in an inclined state, the required main part of the exposed cable core 3 of the main optical cable 1 is required. Even if the optical fiber 6 is cut at its intermediate part and its length is short, each of the fiber cable connecting parts 9 and 10 connected to the optical fiber wire 6 is kept in the inclined state.
4 and 15 can be stably supported. For this reason, each of the core wire connecting portions 9 and 10 is in an unstable supporting state as in the related art, and independently generates vibration due to external vibration or the like, thereby increasing transmission loss or leading to fatigue cutting of the core wire. Can be prevented.

Further, in this embodiment, since each of the core-connection-portion storage trays 14 and 15 is supported by the extra-length storage tray 13 via the elastic supports 16 and 17, each core-connection-portion storage tray 14 is provided. , 15 are hardly transmitted from the connection box frame 11 side, and each of the core wire connection portions 9, 10 can be protected from external vibration.

[0017]

In the optical cable branch connection section according to the present invention, since the two sets of core wire connection section storage trays are respectively arranged on the extra length storage tray in an inclined state, the exposed optical fiber core of the main optical cable can be used. Even if the required main optical fiber is cut at its intermediate portion and its length is short, each of the connected optical fiber connecting portions is stably supported on the inclined optical fiber connecting portion storage tray. be able to. For this reason, each core wire connection part is in an unstable supporting state as in the conventional case, and causes vibration alone due to external vibration or the like, which increases transmission loss or leads to fatigue cutting of the core wire. Can be prevented.

[Brief description of the drawings]

1A is a side view of an example of an embodiment of an optical cable branch connection section according to the present invention, and FIG. 1B is a plan view of the optical cable branch connection section shown in FIG.

FIG. 2 is a perspective view showing a configuration of a main part in an optical cable branch connection section of the present example.

FIG. 3 is a side view showing a schematic configuration of a conventional optical cable branch connection section.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main optical cable 1A, 1B cable part 2 Outer skin 3 Cable core 4,5 Branch optical cable 6 Main optical core 7,8 Branch optical core 7a, 8a Extra length 9,10 Core connection part 11 Connection box frame 12 Support stand 13 Extra length storage trays 13a, 13b Introducing port 14, 15 core connection section storage tray 16, 17 elastic support 18a, 18b core guide 19a, 19b, 20a, 20b clamp 21a, 21b partition

Claims (2)

[Claims] At least one end of a branch optical cable is exposed in the middle of a main optical cable by stripping its outer surface over a required length to expose a cable core, and adjacent to both ends of the exposed portion of the cable core. The middle part of the required main optical fiber in the exposed cable core is cut, and each cut end of the main optical fiber is taken out from the end of each of the branch optical cables. An optical cable in which the ends of the branch optical cores are connected by a core connection part, respectively, and the cable portions on both sides of the exposed portion of the cable core of the main optical cable and the ends of the branch optical cables are gripped by a junction box frame. In the branch connection portion, a surplus storage tray for storing the surplus portion of each of the branch optical fibers is installed on the junction box frame in a direction parallel to the cable core, and the surplus storage tray is provided. On the top, two sets of core wire connection portion storage trays are respectively arranged in an inclined state such that one end thereof approaches both ends of the exposed portion of the cable core and the other end approaches the extra length storage tray, Each of the optical fiber connection portions is supported on each of the optical fiber connection portion storage trays, and the extra length portions of the branch optical cores are stored on the extra length storage tray, respectively. Optical cable branch connection. 2. The optical cable branch connection part according to claim 1, wherein each of the core wire connection part storage trays is supported by the extra length storage tray via an elastic support.