JP2538333Y2 - Optical cable - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to a single groove in the longitudinal direction,
Alternatively, the present invention relates to an optical cable in which one or two or more optical fiber ribbons or optical fiber cores are accommodated in a long square groove having a large number of grooves.

[0002]

2. Description of the Related Art In recent years, in the technical field of optical cables, the number of cores of optical fibers has been increased, and for example, optical cables as shown in FIG. 11 have been proposed. In this cable, a plurality of slot rods 1 each accommodating a plurality of optical fiber ribbons 3 in a plurality of grooves 2 formed in the longitudinal direction of the outer periphery are twisted around the outer periphery of the tension member 4 at the center. After the holding tape 5 is applied on the cable core, the sheath 6 of the exterior is covered. According to this cable, the number of optical fibers can be increased to the order of about 1000.

[0003]

However, in the case of the above cable, the optical fiber density relative to the cable diameter cannot always be said to be high, and the number of optical fibers is 3,000 to 40.
When the diameter is set to 00 or more, there is a problem that the cable diameter becomes too large.

Accordingly, the present applicant has proposed a long flexible angular groove 11 having a single square groove 12 as shown in FIG. 4, for example, and a plurality of light beams are provided in the square groove 12 of the square groove 11. A fiber core 13 (a single-core optical fiber is also acceptable) is placed, and a plurality of the angular grooves 11 are twisted around the center tension member 4 as shown in FIG. 5 to form a cable core. further on, twisting a plurality of corner groove 11, after performing such pressing tape, finally coating the sheath 16, a method of obtaining an optical cable C _1, as shown in FIG. 6, FIG. 7 As described above, a long parallel groove 11 in which a plurality of square grooves 12 are arranged in a comb shape.
A plurality of optical fiber tape cores 13 are placed in each groove 12 of A, and the parallel angle grooves 11A, 11A are butted back to back. For example, as shown in FIG. the sheath 16 has embedded tension member 14, 14 to the left and right sides to cover obtain an optical cable C ₂ method, furthermore, a flexible parallel angle groove 1 having the structure such as shown each groove 12 can be divided into 9
1B and with the central tension member 14 is stranded collectively the outer periphery of such as in Figure 5, proposes a like method to obtain the same optical cable C ₁ and 6, the optical fiber count, 3000-4
Although an ultra-high-density optical cable of 000 or more or a simple optical cable having a number of cores of about several hundreds to 1,000 has been obtained, the following points to be improved have been found.

That is, the above-mentioned square grooves 11, 11A, 1
If the groove 1B is made of a material having a small Young's modulus (kg / mm ² ) or the shape of each groove 12 is carelessly designed, the square groove 1B may be present at the time of manufacture or after installation.
When an external force acts on the first groove 11A, 11B, for example, taking the square groove 11A as an example, as shown in FIG.
The second side wall (rib) 12a is bent. When the groove side wall is bent in this way, it naturally affects the optical fiber ribbon 13 accommodated therein, and for example, there is a problem that the transmission characteristics are deteriorated due to side pressure from the side wall or bending of the tape itself. there were.

The present invention has been made in view of such circumstances.

[0007]

SUMMARY OF THE INVENTION According to the present invention, there is provided an optical cable having an angular groove having one or more optical fiber ribbons or optical fibers in the groove having one or more grooves. Wherein the square groove member has a Young's modulus of 150 kg / mm ² or more, an inner width of the groove of 2.0 to 3.5 mm, and a side wall height of 10.0 m.
m or less, the optical cable has a side wall thickness of 0.7 mm or less.

[0008]

As described above, according to the present invention, since the Young's modulus of the angular groove is increased, a side wall which is not easily bent by an external force, particularly, a lateral force with respect to the groove, is secured. The state is maintained, and good transmission characteristics are obtained.

[0009]

1 to 3 show various embodiments of a square groove used in an optical cable according to the present invention. FIG.
Shows a long parallel angle groove 111A in which a plurality of square grooves 112 are arranged in a comb shape, FIG. 2 shows a long flexible angle groove 111 having a single square groove 112, and FIG. A flexible parallel angle groove 111B having a structure that can be divided is shown.

The corner groove 1 shown in FIG.
When 11A is used, an optical cable according to the present invention having the same structure as that of FIG. 8 described above is obtained, and when the angle grooves 111 and 111B of FIGS. 2 to 3 are used, the same structure as that of FIG. An optical cable according to the present invention is obtained.

Each corner groove 1 used in the present invention as described above.
11, 111A and 111B each have a Young's modulus of 15
0 kg / mm ² or more of resin, for example, polyetherimide, etc., and in the shape of a groove, the inner width w of the groove is 2.0 to 3.5 mm and the height h of the side wall is 10.0 mm
In the following cases, the thickness t of the side wall (rib) 12a is 0.7 mm
It is as follows.

Here, the Young's modulus of each square groove member is set to 1
Was set to 50 kg / mm ² or more, the groove dimensions structure as described above, the Young's modulus of less than 150 kg / mm ^2, strength weak, the force of the side wall 112a is laterally, because so bent It is. In other words, the selection of the square groove member and the dimensional structure of the groove make the side wall 11
2a can have a sufficient strength, and even when the cable is manufactured or laid, it is not easily bent by an external force. Therefore, the corner grooves 111, 111A,
In the optical cable of the present invention using 111B, the original shape of the groove is always maintained normally, the adverse effect on the optical fiber ribbon or the optical fiber core housed therein is minimized, and Good transmission characteristics are obtained.

[0013]

As apparent from the above description, in the optical cable of the present invention, the Young's modulus of the square groove member used is 150 kg / mm ² or more, and the inner width of the groove is 2.0 to 2.0 kg / mm ^2.
When the side wall thickness is 3.5 mm or less and the side wall height is 10.0 mm or less, the side wall thickness is 0.7 mm or less. At all times, the original shape of the groove is normally maintained, and the adverse effect on the optical fiber ribbon or the optical fiber core housed inside is minimized, resulting in good usability and excellent transmission characteristics. .

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a square groove used in an optical cable according to the present invention.

FIG. 2 is a longitudinal sectional view showing another embodiment of the corner groove used in the optical cable according to the present invention.

FIG. 3 is a longitudinal sectional view showing another embodiment of the corner groove used in the optical cable according to the present invention.

FIG. 4 is a longitudinal sectional view showing a corner groove.

FIG. 5 is a perspective view showing an optical cable core using a square groove.

FIG. 6 is a longitudinal sectional view showing an optical cable completed from the optical cable core of FIG. 5;

FIG. 7 is a perspective view showing a parallel angle groove.

8 is a longitudinal sectional view showing an optical cable using the parallel-angle groove of FIG. 7;

FIG. 9 is a perspective view showing another parallel angle groove.

FIG. 10 is a perspective view showing a bending of a side wall in the parallel groove of FIG. 7;

FIG. 11 is a longitudinal sectional view showing a conventional optical cable.

[Explanation of symbols]

 111 angle groove, 111A parallel angle groove, 111B parallel angle groove, 112 groove, 112a sidewall, 13 optical fiber ribbon, 16 sheath,

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Suehiro Miyamoto 1440, Mukurosaki, Sakura-shi, Chiba Fujikura Electric Wire Co., Ltd.Sakura Plant Inside

Claims (1)

(57) [Scope of request for utility model registration] 1. An optical cable having an angular groove in which one or two or more optical fiber ribbons or optical fiber cores are accommodated in said groove of the angular groove having one or a plurality of grooves, wherein said angular groove member is provided. Young's modulus of 15
0 kg / mm ² or more and the inner width of the groove is 2.0 to 3.5
An optical cable characterized in that when the thickness of the side wall is 10.0 mm or less and the side wall thickness is 0.7 mm or less.