JPH11271577A - Optical prefab cable - Google Patents

Abstract

(57) [Summary] [PROBLEMS] When vertically laying an optical prefabricated cable applied to a condominium, an office building, etc., the optical prefabricated cable is attached to a fixing member such as a cable shaft 18 so that rear branching work can be easily performed. In some cases, the binding member 22 binds and fixes. At this time, since the optical fiber cable 16 does not have a sheath, the lateral pressure of the binding member 22 is applied to the optical fiber cord 12, which causes an increase in loss. SOLUTION: A mold portion 24 is formed at an appropriate interval in a longitudinal direction of an optical fiber cable 16. In addition, the binding member 22 is integrally molded therewith. In this case, the optical fiber cable 16 is strongly tightened with the binding member 22.
Is fixed, no side pressure is applied to the optical fiber cord 12 because of the presence of the molded portion 24. Further, since the optical fiber cable 16 is provided with the binding member 22, the cable can be efficiently fixed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical prefabricated cable applied to condominiums (condominiums), office buildings and the like.

[0002]

2. Description of the Related Art As shown in, for example, FIG. 2 (Telecommunications Association: Piping and Wiring Guidebook, p. 43), a cable with a jacket is generally laid from the MDF to the floor IDF of each floor, and the inside of the IDF is laid. Is connected to the floor optical cable by a connector or fusion bonding and used (the same applies to the installation of an apartment house). Therefore, in order to simplify the cable laying and construction, it is desired to make the cable prefabricated. In general, an optical cable in a premises or an apartment house with an outer jacket is fixed to a fixing member such as a cable shaft from above the outer jacket using an insul lock or a cable tie when laying vertically.

[0003] However, in an optical prefabricated cable which is assumed to be pulled down to each floor, the optical prefabricated cable is used without an outer jacket in order to be prefabricated. For this reason, as shown in FIG. 3 (a), the optical cable 16 is attached to a vertical cable shaft 18 or the like so that such a cable can be easily branched afterward. In the case where the optical cable 16 is fixed by the member 22, since the optical cable 16 is not sheathed, there is a problem that the lateral pressure caused by the binding member 22 is applied to the optical fiber cord, which causes an increase in loss.

The optical fiber cable 16 has six optical fiber cords 12 as shown in FIG.
Are gathered around the tension member 14.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an optical prefabricated cable which does not have a fixing problem due to the absence of a sheath in the optical fiber cable 16 as described above.

[0006]

Means for Solving the Problems The first aspect of the present invention is shown in FIG.
Referring to, the molding part 24 is formed around a part of the optical fiber cable 16 in the longitudinal direction, and at this time, the relative distance between the molding part 24 and the optical fiber cable 16 is relatively small. And the binding member 22 is molded integrally with the mold part 24.

The above-mentioned "part of the optical fiber cable 16 in the longitudinal direction" means that the optical fiber cable 16 is not formed over the entire length, but formed, for example, every 2 to 4 m.

The mold section 24 can be manufactured by covering a predetermined position with a split mold, inserting the binding member 22, and performing injection molding. The molding material is, for example, polyurethane, PVC, rubber or the like.

The above-mentioned "relative movement between the mold section 24 and the optical fiber cable 16 is restricted" means that the optical fiber cable 16 is wired vertically and the mold section 24 is This is because when fixed, only the optical fiber cable 16 does not slip down due to its own weight. The outermost layer (sheath) of the optical fiber cord 12 is usually vinyl. At the time of molding the mold part 24, the mold part 24 is fixedly attached to the mold part 24, so that it is possible to sufficiently resist slip-off.

As described above, a well-known insul lock, cable tying string, or the like is used for the tying member 22.

With the molded portion 24, even when the optical fiber cable 16 is tightened by the binding member 22, no side pressure is applied to the optical fiber cord 12.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. In addition, (a) of the figure is an explanatory view of the A section of (b), (b) is a side view near the mold portion 24, and (c) is an explanatory view of a laid state. The optical fiber cable 16 has an outer diameter of 2.8 to 3.0 m.
m optical fiber cords 12 are twisted and assembled around the tension member 14, for example,
This is a structure in which two wires are branched at a predetermined position, and two wires are further branched therefrom.

[0013] A PVC mold portion 24 was formed at intervals of 2 to 4 m in the six twisted portions. Its thickness t
Is 10 to 20 mm (FIG. 1B). Binding member 2
For 2, a publicly known insulator was used.

At the time of laying, as shown in FIG. 1C, the optical fiber cable 16 is attached to the cable shaft 18, the binding member 22 is passed through the hole 20, and tightened to fix.

[0015]

According to the present invention, even when the optical fiber cable 16 is fixed by being strongly tightened by the binding member 22, the side portion pressure is not applied to the optical fiber cord 12 because of the presence of the molded portion 24. Therefore, there is no loss increase. Since the binding member 22 is attached to the optical fiber cable 16, the cable can be fixed efficiently.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of a wiring system using an optical prefabricated cable.

FIG. 3 is an explanatory diagram of a conventional technique.

[Description of Signs] 12 Optical fiber cord 14 Tension member 16 Optical fiber cable 18 Cable shaft 20 Hole 22 Binding member 24 Mold part

Continuing from the front page (72) Inventor Tatsuya Omori 1440 Mukurosaki, Sakura City, Chiba Prefecture Inside Fujikura Sakura Factory Co., Ltd. Person Suehiro Miyamoto 1440 Mutsuzaki, Sakura City, Chiba Prefecture Fujikura Sakura Plant Co., Ltd.

Claims (1)

[Claims] An optical fiber cable in which optical fiber cords are assembled is formed around a part of the optical fiber cable in a longitudinal direction to form a molded part.
4 and the optical fiber cable 16 are in a state in which relative movement is restrained, and the binding member 22 is integrally molded with the molding portion 24. Optical prefab cable.