JPH10115741A - Pipe collection cable for letting optical fiber through - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make running pipes neither deform nor collapse and, therefore, cause neither a manufacture defect nor a laying defect when the pipe collection cable for letting an optical fiber through is manufactured and laid. SOLUTION: The center body 12 of the pipe collection cable 10 for letting an optical fiber through is formed of a hollow body 22A which deflects and restores itself radially, and this hollow body 22 has lower hardness than running pipes 14 gathered around it. Therefore, even if external pressure is applied to the running pipes 12 radially when the collection cable 10 is manufactured and laid, the center body 12 deflects radially through the running pipes 14 having relatively higher hardness than the center body 12 because of its flexibility to absorb the external pressure and when the external pressure is removed, the center body 12 restores itself to its original state, so the running pipes 14 neither deform nor collapse.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in an optical fiber transmission pipe assembly cable used to be laid in advance so that an optical fiber can be transmitted later according to an increase in demand. .

[0002]

2. Description of the Related Art With the spread of multimedia, optical fibers are being drawn into homes, and it is expected that the drawing of optical fibers will increase further in the future.
For this reason, an optical fiber transmission cable formed by assembling a large number of transmission pipes capable of transmitting the optical fiber later so that the optical fiber can be drawn into the home if necessary. Has been laid.

[0003] This type of optical fiber transmission cable 1
Numeral 0 denotes a solid central body 12 such as polyvinyl chloride or low-density polyethylene, a plurality of optical fiber transmitting pipes 14 assembled therearound as shown in FIG. 14 and a coating 18 applied through a presser winding 16. As shown in FIG. 3, the covering 18 integrally has a covering portion 18A covered by a suspension member 20 made of a tensile strength member. Therefore, the collective cable 10 is a self-supporting collective cable.

[0004] The collective cable 10 is previously laid close to each home, and when the optical fiber is drawn into the home, the optical fiber is inserted into a predetermined transmission pipe 14 in the collective cable 10 by air blow or the like. We send while sending by pressure.

[0005] The collective cable 10 is manufactured while being taken by a take-off machine or the like in manufacturing processes such as a pipe collecting process and a coating process. However, in the collective cable of the prior art, the central body 12 is formed of a solid rod-shaped body having no flexibility in the radial direction. When pressure is applied, the transmission pipe is plastically deformed and crushed by being backed by a solid central body, so that a defective cable assembly may be produced.

Further, when laying a non-defective collective cable 10 having a non-collapsed transmission pipe 14, an excessive external pressure such as bending, lateral pressure, impact or the like is applied to the collection cable 10 so that the transmission pipe 14 may be interrupted. May remain crushed,
For this reason, the optical fiber may not be able to be transmitted through the transmission pipe 14 later.

[0007]

The problem to be solved by the present invention is that the transmission pipe is not deformed or crushed at the time of manufacturing and laying, and therefore, there is no production defect and laying defect. An object of the present invention is to provide an optical fiber transmission pipe aggregate cable.

[0008]

SUMMARY OF THE INVENTION The object of the present invention is to provide an optical fiber transmission pipe aggregated cable formed by assembling a plurality of transmission pipes for optical fiber transmission around a central body. Comprises a flexible member having flexibility and restorability in the radial direction, and the flexible member has a lower hardness than the transmission pipe, and provides an optical fiber transmission pipe aggregated cable. It is in.

[0009] In the means for solving the problems of the present invention, the flexible member is typically formed of a hollow pipe, but has flexibility and restorability, and has a lower hardness than the feed pipe. If possible, it can be made of a foam material such as a sponge-like material other than the hollow pipe.

As described above, the center body is made of a flexible member having flexibility and restoring ability in the radial direction, and this flexible member has a lower hardness than the communication pipe assembled therearound. Then, at the time of manufacturing and laying the collective cable, even if external pressure is applied to the transmission pipe in the radial direction, the central body flexes in the radial direction to absorb the external pressure, and when the external pressure is released, Since it is restored to the original state, the transmission pipe will not be plastically deformed or collapsed, so that it is impossible to manufacture the optical fiber transmission pipe aggregated cable or the optical fiber transmission is impossible. It doesn't fall.

Further, since the transmission pipe has a higher hardness than the central body, it is possible to maintain a sufficient hardness to prevent the optical fiber from being pumped when the optical fiber is fed into the inside of the pipe. Since the weight of the collective cable as a whole is reduced, cost reduction and ease of handling can be ensured.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows one embodiment of an optical fiber transmission pipe aggregate cable 10 according to the present invention. As shown in FIG. 1, the fiber transmission pipe aggregate cable 10 includes a center body 12, a plurality of transmission pipes 14 for optical fiber transmission assembled around the center body 12, and a press winding on the transmission pipe 14. Coating 1 applied via 16
It consists of eight. The coating 18, as shown in FIG.
The suspension member 20 made of a high-strength body has an integral covering portion 18A covered with the suspension member 20.
Is shown in a self-supporting form.

As shown in FIG. 1, the center body 12 is composed of a flexible member 22 having flexibility and restoring properties in the radial direction. In the illustrated embodiment, the flexible member 22 has a lower hardness than the transmission pipe 14, and has a thickness of 1 mm, for example.
It consists of the hollow body 22A made of low density polyethylene described above. On the contrary, since the communication pipe 14 has a higher hardness than the flexible member 22 which is the central body 12, the flexible member 2
If 2 is made from low density polyethylene, it can be made from high density polyethylene. In the embodiment shown in FIG. 1, the plurality of transmission pipes 14 are assembled so as to form one aggregate layer.

As described above, the center body 12 is composed of the flexible member 22 having flexibility and restoring properties in the radial direction, and the flexible member 22 is formed around the transmission pipe 14 around which the flexible member 22 is assembled. With a lower hardness, the central body 12 maintains its backing action due to its flexibility even when a radial external pressure is applied to the transmission pipe 12 during manufacturing or laying of the collective cable 10. Instead, it deflects radially through a transmission pipe 14 having a hardness higher than that of the central body 12 to absorb the external pressure, and when the external pressure is released, the original state is restored. Therefore, since the transmission pipe 14 does not plastically deform during production or remains crushed during installation, the production of the optical fiber transmission pipe aggregate cable 10 becomes impossible, and the transmission of this aggregate cable becomes impossible. It is not impossible to pass an optical fiber through the pipe 14.

Further, since the transmission pipe 14 has a relatively higher hardness than the central body 12, the pressure of the optical fiber is not hindered when the optical fiber is pressure-fed into the inside thereof by air blow or the like. Hardness can be maintained. The presser winding 16 is provided for each assembly layer.

Another embodiment of the present invention is shown in FIG. 2, in which a plurality of transmission pipes 14 are
Hollow body 2 having flexibility to form two aggregate layers
It is gathered around a central body 12 of 2A. Also in this embodiment, similarly to the embodiment of FIG. 1, when an external pressure in the radial direction is applied at the time of manufacturing or laying the collective cable 10, the external pressure is applied to the transmission pipes of the two collective layers. Since the transmission pipe 14 is absorbed by the central body 12 composed of the hollow body 22A through the transmission pipe 14, the transmission pipe 14 is not plastically deformed or crushed.

In the above two embodiments, the central body 12
Is made of a hollow pipe, but if the flexible member 22 has flexibility and resilience in the radial direction, the hollow body 2
Not limited to 2A, for example, it may be made of a foam material. The presser winding 16 is provided for each layer.

[0018]

According to the present invention, as described above, the central body of the optical fiber transmission pipe assembly cable is formed of a flexible member having flexibility and restorability in the radial direction. Since the conductive member has a lower hardness than the transmission pipe assembled around it, even when a radial external pressure is applied to the transmission pipe at the time of manufacturing and laying the collective cable, the central member is formed through the transmission pipe. The body flexes in the radial direction to absorb this external pressure, and when the external pressure is released, it returns to its original state, so that the transmission pipe does not plastically deform or remain crushed, It is not impossible to manufacture the fiber transmission pipe aggregate cable or to prevent the optical fiber from being transmitted.

Further, since the transmission pipe has a relatively higher hardness than the central body, when the optical fiber is pressure-fed into the inside thereof by air blow or the like, the hardness is such that the pressure of the optical fiber is not hindered. In addition, since the central body is made of a flexible, low-density material, the weight of the collective cable as a whole can be reduced, and cost reduction and easy handling can be ensured.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of one embodiment of an optical fiber transmission pipe aggregate cable according to the present invention.

FIG. 2 is a cross-sectional view of another embodiment of the optical fiber transmission pipe aggregate cable according to the present invention.

FIG. 3 is a cross-sectional view of one conventional optical fiber transmission pipe aggregate cable.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Optical fiber transmission pipe collective cable 12 Central body 14 Transmission pipe 16 Holding winding 18 Coating 18A Coating part 20 Suspension member 22 Flexible member 22A Hollow body

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Kazuo Hokari, Inventor, Nippon Telegraph and Telephone Corporation 3-9-1, Nishishinjuku, Shinjuku-ku, Tokyo (72) Inventor Shinichi Furukawa 3-192, Nishishinjuku, Shinjuku-ku, Tokyo No. Japan Telegraph and Telephone Corporation

Claims (2)

[Claims] 1. An optical fiber transmitting pipe assembly cable formed by collecting a plurality of optical fiber transmitting pipes around a central body, wherein the central body has flexibility and restorability in a radial direction. An optical fiber transmission pipe assembly cable, comprising: a flexible member having a lower hardness than the transmission pipe. 2. The collective cable for transmitting optical fibers according to claim 1, wherein the flexible member is formed of a hollow pipe.