JP2557097Y2 - Optical composite submarine cable - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION INDUSTRIAL APPLICATION This invention relates to an optical submarine cable in which a power cable core for power transmission and an optical fiber unit for optical communication are integrated.

2. Description of the Related Art As is well known, an optical fiber propagates light by using total reflection based on a difference in refractive index, and in addition to directly transmitting an image, a semiconductor laser in which light emission intensity is changed by an electric signal. Such optical signals are widely used in optical communication in which optical signals are transmitted to a distant place and the light is converted into electric signals by a photodetector.
In addition, since optical fibers are non-inductive, they can be installed side-by-side with high-voltage transmission lines for transmitting power.Therefore, optical composites have been conventionally used in which optical cables are inserted into submarine cables laid between the mainland and islands. Submarine cables and optical fiber composite overhead ground wires in which optical fibers are inserted into ground wires for overhead transmission lines have been developed. Among these, the conventional general optical composite submarine cable has a plurality of optical fibers arranged on the outer periphery of a power cable core composed of a conductor for power transmission and an insulator provided on the outer periphery thereof, and further has strength retention on the outer periphery. It is a structure provided with an iron wire cladding, an anticorrosion layer or a presser winding, and has the following technical problems.

The basic difference in the arrangement of the optical fiber unit between the above-mentioned optical submarine cable and the ordinary submarine optical cable is that in the optical submarine cable, the optical fiber unit is arranged around the power cable core. As described above, the displacement of the optical fiber unit when it is bent is larger in the optical submarine cable than when the optical fiber unit is located at the center in the submarine optical cable. On the other hand, in an optical submarine cable, the number of optical fiber units that can be arranged is considerably large because optical fiber units are arranged on the outer periphery of the power cable core, but the number of optical fiber units required for practical use is Since there is not enough to fill the whole, in the conventional optical submarine cable, a gap is provided between the optical fiber units arranged on the outer periphery of the power cable core.

Therefore, in the conventional optical composite submarine cable, the arrangement of the optical fiber units is easily disturbed when subjected to bending or twisting,
Further, a crushing force is easily applied directly to the optical fiber unit, and as a result, there is a possibility that transmission loss increases.

This invention was made in the background of the above circumstances,
It is an object of the present invention to provide an optical composite submarine cable that can prevent disturbance of a winding state of an optical fiber unit.

Means for Solving the Problems In order to achieve the above object, the present invention provides an optical fiber in which a plurality of optical fiber units are inserted between a power cable core for transmitting power and an iron wire armor for maintaining strength. In the composite submarine cable, the optical fiber core is inserted into the inside of the anticorrosion-coated pipe and the jelly is filled to form the optical fiber unit, and between the optical fiber units, substantially the same as the optical fiber unit. A flexible filament having an outer diameter is closely interposed so as to fill the gap between the optical fiber units, and jelly is filled between the optical fiber unit and the flexible filament and between the flexible filaments. It is characterized by the following.

In the optical composite submarine cable of the present invention, since the optical fiber units are arranged on the outer periphery of the power cable core, the optical fiber unit on the inner peripheral side and the optical fiber unit on the outer peripheral side when bent are used. Is large, and the force causing the optical fiber unit to be displaced increases. On the other hand, in the present invention, since the flexible wire and the jelly are filled between the optical fiber units, the displacement of the optical fiber unit is regulated, and the winding state is not disturbed. . In addition, since the flexible filament has substantially the same outer diameter as the optical fiber unit, the flexible filament receives the crushing force, and at the same time, the jelly maintains the internal pressure at the location where the optical fiber unit is filled. As a result, the crushing force applied to the optical fiber unit is reduced.

Embodiment Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of the present invention.
The power cable core 1 includes an insulator 3, an outer diameter 4, and a reinforcing layer 5 which are sequentially provided on the outer circumference of the conductor 2 to a required thickness, respectively. The corrosion protection layer 6 is formed on the outer circumference of the reinforcing layer 5. I have. For the insulator 3, the outer cover 4, the reinforcing layer 5, and the anticorrosion layer 6, various conventionally known configurations and materials can be adopted according to the power transmission capacity, the installation depth, and the like. A plurality of optical fiber units 7 are spirally wound around the outer periphery of the anticorrosion layer 6 at regular intervals.
A flexible linear body such as a polyethylene string 8 is disposed as an intervening member between the optical fiber units 7. Therefore, the polyethylene string 8 is also spirally wound around the outer periphery of the anticorrosion layer 6 like the optical fiber unit 7. It is wound in a shape. Here, an example of the optical fiber unit 7 is as shown in FIG. That is, the optical fiber core wire 9
Is inserted into a metal pipe 10 of stainless steel or the like, the jelly 11 is filled in the metal pipe 10, and an anticorrosion layer 12 made of polyethylene or the like is formed on the outer periphery of the metal pipe 10 to form a cross section as a whole. It has a circular configuration. On the other hand, the polyethylene string 8 as an inclusion
The outer diameter, that is, the radial dimension of the cable wound around the anticorrosion layer 6 is the same as that of the optical fiber unit 7, and the gap between the optical fiber units 7 is almost completely It is arranged to fill in.
No optical fiber unit 7 to prevent water running
Jelly is filled in the minute gap between the polyethylene strings 8.

The optical fiber unit 7 and the polyethylene string 8 are fixed by presser windings 13 provided on the outer periphery. Further, a plurality of steel wires are closely wound around the outer periphery thereof, and an iron wire armor 14 is formed.

FIG. 3 is a cross-sectional view showing another embodiment of the present invention, in which a seat floor layer 15 is formed on the outer periphery of the power cable core 1 including the conductor 2, the insulator 3, the jacket 4, and the reinforcing layer 5. An optical fiber unit 7 and an intervening polyethylene string 8 are spirally tightly wound around the outer peripheral surface. Therefore, also in the example shown in FIG. 3, the optical fiber units 7 are filled with the polyethylene string 8 between them.

An anticorrosion layer 6 is formed on the outer periphery of the optical fiber unit 7 and the polyethylene string 8, and an iron sheath 14 is formed on the outer periphery.

Therefore, in the configuration shown in FIG. 1 or FIG. 3, there is no gap on both the inner and outer circumferences of each optical fiber unit 7 and also on the left and right sides in the circumferential direction. The position of the fiber unit 7 is regulated by the polyethylene string 8, so that the winding state is not disturbed.

In each of the above embodiments, an example was shown in which a polyethylene string was used as a flexible striated body for intervention, but the present invention is not limited to the above embodiment, and a flexible striated body is used. If so, it can be used in place of the polyethylene string described above.

Effect of the Invention As is clear from the above description, according to the invention, the optical fiber unit configured by inserting the optical fiber core wire into the inside of the anticorrosion coated pipe and filling the jelly is a flexible linear body for intervention. Because the position is regulated by, the winding state is not disturbed even when bending is applied, and the flexible filament has substantially the same outer diameter as the optical fiber unit. Since the space between the optical fiber units is filled, the crushing force acting on the optical fiber unit when the cable is bent is reduced. As a result, in the present invention, the deformation or the external force due to the disorder of the winding state of the optical fiber unit is reduced, so that a high-performance optical submarine cable with small transmission loss can be obtained. In addition, since the jelly is filled between the optical fiber units together with the flexible striated body, water running is prevented together with the reduction of the crushing force on the optical fiber unit to improve durability. be able to.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, FIG. 2 is a sectional view showing an example of an optical fiber unit, and FIG. 3 is a sectional view showing another embodiment of the present invention. 1: Power cable core, 7: Optical fiber unit, 8:
Polyethylene string, 14 ... iron wire armor.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shotaro Yoshida 1-5-1 Kiba, Koto-ku, Tokyo Inside Fujikura Electric Wire Co., Ltd. (72) Inventor Mitsugu Matsuda 1-5-1 Kiba, Koto-ku, Tokyo Fujikura Inside the Electric Wire Co., Ltd. (72) Inventor Kazuo Ohata 1-5-1, Kiba, Koto-ku, Tokyo Fujikura Electric Wire Co., Ltd. (72) Inventor Koichiro Fujii 6-15-1, Ginza, Chuo-ku, Tokyo Inside Power Development Co., Ltd. (56) References JP-A-50-37446 (JP, A) JP-A-61-13413 (JP, U) JP-A-56-9616 (JP, U) JP-A-55-133408 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] An optical composite submarine cable in which a plurality of optical fiber units are inserted between a power cable core for transmitting power and an iron wire armor for maintaining strength, wherein an optical fiber core is provided inside a corrosion-protected coated pipe. The optical fiber unit is formed by inserting a wire and filling the jelly, and a flexible linear body having substantially the same outer diameter as the optical fiber unit is formed between the optical fiber units. An optical composite submarine cable characterized by being densely interposed so as to fill the gap, and further filled with jelly between the optical fiber unit and the flexible filament and between the flexible filaments.