JPH058564Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention is for connecting optical fiber cables, such as communication optical fiber cables, which are made of multi-core wires covered with metal sheaths and jackets, to repeaters, etc. The present invention relates to an optical fiber cable termination section that can be applied to a core wire lead-out section of an optical fiber cable in cases such as when

[Conventional technology]

When connecting an optical fiber cable to a repeater or the like, it is necessary to accommodate the optical fiber cable in a repeater housing or the like, and to lead out and connect the optical fiber core wire. In this case, the optical fiber cable is fixed within the housing to protect the optical fiber core. In the case of conventional metal cables, external pressure does not cause transmission loss, but in the case of optical fiber cables, external pressure causes optical loss and breakage of the core wire. Sometimes. Therefore, when fixing the cable end when processing the end of the optical fiber cable, it is necessary to use rubber or
Cables were fixed using cable bushings made of PVC material. For example, when an optical fiber cable has a metal sheath on the outside of the optical fiber core, when this metal sheath needs to be grounded, a lead wire is soldered to it. It was designed to be grounded through the wire.

[Problem that the invention attempts to solve]

At the end of the conventional optical fiber cable, if the cable bushing is made of soft material such as rubber or PVC, the cable bushing may bend due to the pressure applied when tightening the cable bushing from the outside. This may cause optical loss, and the core wire is likely to break when the optical fiber core wire is drawn out through this wire.Furthermore, if the metal sheath is to be grounded, it is necessary to solder the metal sheath and the lead wire. Therefore, there were problems such as poor workability and a large connecting portion.

The present invention solves the above-mentioned conventional problems, and provides an optical fiber cable that prevents optical loss at the terminal portion of the optical fiber cable and bending and breakage of the core wire, and allows for easy and reliable connection between the metal sheath and the ground. The purpose is to provide a termination section.

[Means for solving problems]

The optical fiber cable termination section according to the present invention is provided in a core wire lead-out section of an optical fiber cable in which a metal sheath is applied to the outer periphery of an optical fiber core wire, and a jacket is applied to the outer periphery of the metal sheath. It has a divided outer sheath formed by dividing it into a plurality of parts in the longitudinal direction, and a tongue piece for grounding at one end, the outer periphery is covered with the metal sheath and the divided outer sheath, and the optical fiber core wire is inside. It is characterized by comprising a protective fitting made of a hollow cylinder formed to be inserted through the protective fitting, and a protector covering the outer periphery of the metal sheath covering the protective fitting and the outer periphery of the divided outer covering, respectively. It is something to do.

[Effect]

According to the present invention, a metal sheath is applied to the outer periphery of the optical fiber core wire, and a protection member having a grounding tongue piece at one end is provided at the core wire lead-out portion of the optical fiber cable, which is formed by applying a metal sheath to the outer periphery of the metal sheath. The optical fiber core wire is inserted into the metal fitting, the core wire is guided out, the outer periphery of the protective metal fitting is covered with the metal sheath and the divided jacket, and the outer periphery is further covered with a protector. Therefore, the pressure due to the clamping force applied to fix the optical fiber cable at the optical fiber lead-out section is absorbed by the protective fitting, and this prevents the optical fiber from being affected by external pressure. This prevents the optical fiber core from bending or breaking due to external pressure and optical loss, and maintains good transmission characteristics, and also maintains good electrical contact between the protective fitting and metal sheath. Therefore, the metal sheath can be easily grounded via the grounding tongue provided on the protective metal fitting. This solves the above-mentioned conventional problems.

[Example] An example of the present invention will be described in detail based on the drawings.

Figures 1A and 1B are diagrams showing the configuration of an embodiment of the present invention, respectively. Figure 1A is a longitudinal cross-sectional view of the main part;
Figure B is a front view, Figures 2A and B are views showing the structure of the protective fittings in Figures 1A and B, respectively.
Figure A is a front view, Figure 2B is a partial cross-sectional side view of Figure 2A, and Figure 3 is a diagram showing a state in which the optical fiber cable termination portion shown in Figures 1A and B is fixed.

In FIGS. 1A, B to 3, 1 is a protective fitting that is attached to a hollow cylinder 2 having an outer diameter slightly smaller than the inner diameter of the metal sheath 10, and to one end of the hollow cylinder 2, for example, to one opening. The collar part 3 and the collar part 3
and a grounding tongue piece 4 integrally formed. Grounding lead wire 1 is attached to the tongue piece 4.
A hole 5 is provided for attaching 5. 6 is an optical fiber cable, 7 is a divided jacket formed by dividing the terminal part of the jacket of the optical fiber cable 6 into a plurality of parts in the longitudinal direction at the core wire lead-out part, 8 is an optical fiber core, and 9 is a tensioner. 10 is a metal sheath applied to the outer periphery of the optical fiber core wire 8; 11 is a protector that covers the outer periphery of the metal sheath 10 and the divided jacket 7 of the protective fitting 1; 12 is an optical fiber cable 6
13 is a fixing fastener, 14 is a fixing screw, and 15 is a grounding lead wire.

An optical fiber cable termination section according to an embodiment of the present invention shown in FIGS. 1A and 1B is constructed as follows. At the core wire lead-out portion of the optical fiber cable 6, the outer sheath of the optical fiber cable 6 is stripped off, leaving the required length of the optical fiber core 8 from the end of the optical fiber cable 6, and the terminal portion is removed. The divided jacket 7 is formed by dividing into a plurality of parts in the longitudinal direction. In this case, the longitudinal dimension of the metal sheath 10 is made to be approximately equal to the longitudinal dimension of the hollow cylindrical body 2 of the protective fitting 1, so that the outer periphery of the hollow cylindrical body 2 can be covered with the metal sheath 10. . The optical fiber core 8 and tension member 9 thus formed are passed through the opening of the hollow cylinder 2 of the protective fitting 1 (the opening that does not have the tongue piece 4) into the hollow cylinder 2.
The outer periphery of the hollow cylindrical body 2 is covered with a metal sheath 10 and a split jacket 7. In this case, since the outer diameter of the hollow cylindrical body 2 is formed to be slightly smaller than the inner diameter of the metal sheath 10, the work of covering the outer periphery of the hollow cylindrical body 2 with the metal sheath 10 can be easily performed, and the metal sheath The contact between 10 and the hollow cylindrical body 2 and the contact between the metal sheath 10 and the protective fitting 1 are in a good electrical contact state.
In order to make the contact between the hollow cylindrical body 2 and the metal sheath 10 even better, a narrow longitudinal groove may be provided on the outer surface of the hollow cylindrical body 2, or a groove or knurling may be provided in the circumferential direction. good. After the outer periphery of the hollow cylindrical body 2 is covered with the metal sheath 10 and the divided jacket 7 as described above, the outer peripheries of the metal sheath 10 and the divided jacket 7 are further covered with tube-shaped protectors 11, respectively. Figure A,
An optical fiber cable termination section as shown in B is constructed.

The operation of the embodiment of the present invention described above will be explained.

When attaching the optical fiber cable 6 to a repeater housing or the like, an optical fiber cable termination portion shown in FIGS. 1A and 1B is formed at the core wire lead-out portion of the optical fiber cable 6. A third metal sheath 10 and a split jacket 7 covering the hollow cylinder 2 at the end of the optical fiber cable and the outer periphery of the protector 11
As shown in the figure, the fixing fastener 13 is brought into contact with the fixing fastener 13, and the fixing fastener 13 is fixed to the fixing plate 12 such as a casing with the fixing screw 14. Tighten and fix. The pressure due to the tightening force of this fixed fastener 13 is applied to the protective fitting 1
It is absorbed by the hollow cylinder 2 and is not added to the optical fiber core 8 and tension member 9 housed inside the hollow cylinder 2. Therefore, bending or breakage of the optical fiber core wire 8 and optical loss due to this external pressure can be prevented. In addition, since the protective fitting 1 and the metal sheath 10 are maintained in good electrical contact, when the metal sheath 10 is grounded at the core wire lead-out section, the grounding tongue provided on the protective fitting 1 is used. By connecting the grounding lead wire 15 to the hole 5 of the piece 4, grounding can be easily achieved.

[Effect of idea]

As described above, according to the present invention, the following excellent effects can be achieved.

(1) At the optical fiber lead-out section, the optical fiber cable can be reliably attached to a fixed plate such as a housing without applying external pressure to the core.

(2) Since no external pressure is applied to the optical fiber,
There is no distortion of the core wire due to external pressure, it is possible to prevent the core wire from bending or breaking, and it is possible to prevent optical loss.

(3) Since the metal sheath can be grounded through the tongue piece of the protective fitting, the metal sheath can be easily and reliably grounded, thereby improving grounding workability and reliability. .

[Brief description of the drawings]

Figures 1A and 1B are diagrams showing the configuration of an embodiment of the present invention, respectively. Figure 1A is a longitudinal cross-sectional view of the main part;
Figure B is a front view, Figures 2A and B are views showing the structure of the protective fittings in Figures 1A and B, respectively.
Figure A is a front view, Figure 2B is a partial cross-sectional side view of Figure 2A, and Figure 3 is a diagram showing a state in which the optical fiber cable termination portion shown in Figures 1A and B is fixed. DESCRIPTION OF SYMBOLS 1... Protective fitting, 2... Hollow cylinder, 4... Tongue piece, 6... Optical fiber cable, 7... Division jacket, 8... Optical fiber core wire, 10... Metal sheath, 11... protector.

Claims (1)

[Scope of utility model registration request] In the core wire lead-out portion of an optical fiber cable, which is formed by applying a metal sheath to the outer periphery of an optical fiber core wire and applying a jacket to the outer periphery of the metal sheath, the terminal part of the jacket is divided into a plurality of parts in the longitudinal direction. a hollow cylindrical body having a divided outer sheath and a grounding tongue piece at one end, an outer periphery of which is covered with the metal sheath and the divided outer sheath, and formed so that the optical fiber core wire can be inserted thereinto; 1. An optical fiber cable termination unit comprising: a protective metal fitting made of aluminum; and a protector that covers the outer periphery of the metal sheath and the split jacket, respectively.