JPS60169815A - Connection end part of cable with optical fiber - Google Patents

Abstract

PURPOSE:To protect an optical fiber from external force, and branching it strongly and to perform branching, connection, etc., to the optical fiber of another equipment by covering an end part of a heat-shrinkable tube which covers the buffer layer of the optical fiber and the jacket of a bundle with a heat- shrinkable tube. CONSTITUTION:An optical fiber bundle 3a and a metallic core 2a are branched into from a clad 11a. Bundles 3a and 3b have plural optical jackets 31a. An optical fiber element wire 33a has the jacket 35a removed at an end part of the bundle 3a to proper length, and the exposed part is run into a heat-shrinkable tube 50 and heated by a proper heating means and sheathed. Then, a heat- shrinkable tube 60 is arranged straddling and covering the end part of the jacket 35a and the optical fiber element wire 33a covered with the hat-shrinkable jacket tube 50, and heated by a heating means to decrease in diameter.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a connecting end of a cable having a plurality of optical fibers.

[Prior art]

As an example of a cable having an optical fiber, the optical fiber core wires are arranged with a suitable number of insulated metallic core wires, and the optical fiber core wires are arranged to be directed to one core or with a suitable number of targets, and,
For example, there are optical/deer composite cables in which a jacket is provided on the outer periphery of these cables. On the other hand, an optical fiber coated wire is usually provided with a secondary coating, a buffer layer, and a jacket in sequence around the outer periphery of the optical fiber. , are arranged so that external forces such as lateral pressure are difficult to apply.

However, the twisted gap is so narrow that it is difficult to arrange the optical fiber core there, that is, the fiber has a plastic thin film and a buffer layer on the optical fiber, and is called a bare fiber. ) are assembled by suitable center twisting, etc., and a jacket made of polyamide, hexafluoroethylene, etc. is applied all at once to the optical fiber group assembled in this way to form an optical fiber assembly. It is sometimes twisted together with core wires to form a cable core, which is then covered with an outer jacket to form a cable.

By the way, when connecting optical fibers together or making a branch connection to other equipment, in order to prevent abnormal phenomena such as tension from being applied to the optical fiber connection point, add extra length to the optical fiber and use a connection aid, for example. The splice piece for the rod, that is, the groove formed in the longitudinal direction of the rod, accommodates both ends of the fiber optics with the optical fiber connection point in the center, and these and the lid body placed over the groove are glued together. A type of material that is fixed in one piece is used.

However, if a plurality of unjacketed optical fibers are twisted together and a jacket is encapsulated on top of the twisted fibers, the optical fibers to be connected will not be coated. Therefore, the connection parts cannot be sufficiently protected. Therefore, if a large tension is applied to this part, there is a risk that the optical fiber will not only break at the connection point, but also be easily damaged during the connection process, and the mechanical strength of this part will be weakened.

[Purpose of the invention]

The connection end of the optical fiber cable of the present invention solves the above-mentioned problems, and is an optical fiber cable in which a jacket is provided on a plurality of optical fiber wires each having no jacket. removing the jacket at the end of the cable having the fiber assembly to be connected and covering each exposed optical fiber with a heat shrink tube;
A heat-shrinkable tube is placed over the jacket and the group of optical fibers covered with the heat-shrinkable tube.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a side view of one embodiment of the present invention, and FIG. 2 is a side view of one embodiment of the present invention.
FIG. 6 is a view taken along the line E' in FIG. 1, FIG. 4 is a view taken along the line .

In FIG. 1, 1a and Ib are cables, and each cable 1a and 1b has a plurality of metallic core wires 2a and 2b, each having a metal conductor coated with an insulator, twisted together (simplified in the figure). Therefore, only one core is shown), and aggregates 6a and 3b formed by jacketing a group of optical fibers are arranged in the gap between the twists.

The cables Ia and 1b each have a jacket 11a at their end,
i and i b are removed, and the metallic core wires 2a and 2b are connected at the connecting portion 20.

Optical fiber aggregates 3a, 3b (6a in Figures 2 to 4)
6b) is an optical fiber in which a thin layer of plastic is provided on the optical fiber 31a and a buffer layer 32a is provided thereon by coating the thin layer with silicone resin or the like, as shown in FIG. Four strands of strands 33a are twisted together and twisted together to fill the gap and form an optical fiber strand 33a.
A buffer layer 5 is formed by covering the outer periphery of the buffer layer 5 with silicone resin or the like.
4a, and a jacket 35a whose outer periphery is coated with thread resin or the like can be seen.

30 is a termination part of the optical fiber assembly 5a, and each optical fiber 31a is branched and connected to an optical fiber (not shown) of the other optical fiber assembly 6b or an optical fiber of another device (not shown) via a connector 40. Each optical fiber 31a is taken out as soon as possible.

The optical fiber wire 33a is removed to an appropriate length from the end portion 55a of the optical fiber assembly 6a as shown by the dotted line in FIG. , heated by an appropriate heating means and encapsulated.

Then, the end of the jacket) 35a and the heat shrink tube 5
A heat-shrinkable tube 6 is placed over the group of optical fiber strands 33a each encapsulated with
0 is placed and heated by an appropriate heating means to reduce the diameter, the heat-shrinkable sleeve 50, 60 may have its inner surface coated with hot melt adhesive or filled with silicone resin, if necessary. Jacket 3
5a, each heat shrink tube 50, heat shrink tube 60
The optical fiber wires 55a are also firmly bonded together.

Each heat shrinkable tube 50 and 60 used in the present invention
is a known material such as vinyl, crosslinked polyethylene, fluororesin, silicone rubber, etc., and may be used as long as it protects the optical fiber 31a from external forces such as lateral pressure and tension.

Further, the other optical fiber assembly 6b is also processed simultaneously with the aforementioned optical fiber assembly 3a.

〔effect〕

As mentioned above, the connecting end of the fiber optic cable of the present invention can be used to connect individual non-jacketed optical fibers in the cable to other optical fibers, and
Suitable for branching and connecting optical fibers of other devices, a heat-shrinkable tube is placed over the loose layer provided on the optical fiber, and the end of the heat-shrinkable tube and the optical fiber assembly are A heat-shrinkable tube is placed over the jacket.

Therefore, each optical fiber is protected from external forces by the heat-shrinkable tube, and is firmly branched.
It can be connected to other optical fibers, or branched or connected to other equipment's optical fibers.

[Brief explanation of drawings]

Fig. 1 is a side view of one embodiment of the present invention, Fig. 2 is a view taken along the line E' of Fig. 1, Fig. 3 is a view taken along the Rollo l line of Fig. This is a diagram showing the arrows in the figure. In the figure, 1a and 1b are cables, 2a12b is a metallic core wire, 5a3b is an optical fiber assembly, 30 is an optical fiber termination part, 33a is an optical fiber wire, 50 and 6
01-j: Each is a heat shrinkable tube, and 70 is an adhesive. Patent registration applicant Dainichi Nippon Electric Cable Co., Ltd. Representative Director Ao Yamayuki Kiji

Claims (1)

[Claims] An optical fiber element exposed by removing the jacket at the end of a cable to be connected, which has an optical fiber assembly in which a plurality of optical fiber elements each having no jacket is provided with a socket socket. A cable connection having an optical fiber, characterized in that a heat shrinkable tube is placed on each wire, and a heat shrinkable tube is placed over the group of optical fibers covered with the heat shrinkable tube and the jacket. edge.