JPS62231915A - Optical fiber cable - Google Patents

Abstract

PURPOSE:To strip off a sheath and to take out an optical fiber without cutting the optical fiber by putting plural optical fibers dispersedly in an LAP sheath pipe, and sheathing the outer periphery of the LAP sheath pipe by distributing a high-tensile strength material. CONSTITUTION:The high-tensile strength material ('Kevlar(R)') 3, a corrugated steel tape 4, and a polyethylene sheath 5 are provided longitudinally around the outer periphery of the LAP sheath pipe 2 wherein six optical fibers 1 are stored freely in a dispersed state. The corrugated steel table 4 and polyethylene sheath 5 hold pressure resistance and curving performance together with the high-tensile strength material 3. At the same time, the sheath which functions as a buffer layer for external lateral pressure is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fiber optic cable containing a plurality of optical fibers, particularly for use in subscriber or local area network systems (LoaaL Area Network systems).
This article concerns the structure of optical 7-fiber cables used in systems such as Lystem.

[Conventional technology]

Conventional optical fiber cables (hereinafter referred to as optical cables) generally have optical fibers arranged and fixed around the outer periphery of a tensile strength material.
An optical fiber with a jacketed structure (hereinafter referred to as prior art 1) or a tape-shaped optical fiber in which a plurality of optical fibers are arranged in a row and the outer periphery is coated and the optical fibers are fixed, for example, laminated aluminum polyethylene 7 (LAP)
A structure that can be inserted into a pipe (hereinafter referred to as prior art 2) is used.

[Problem that the invention seeks to solve]

Conventional technology 1 for placing and fixing optical fibers around the outer periphery of tensile strength material
When optical cables are used in systems that input light from any intermediate position of the optical fiber and couple it with external terminal equipment, it is extremely difficult to identify and extract the optical fiber without cutting it. . The optical cable of prior art 2, in which tape-shaped optical fibers are inserted into a pipe, is arranged in a tape-like manner, making it easy to identify the optical fibers. , it takes effort to take it out from any intermediate position.

There is a problem in that it impedes workability.

[9th method to solve problems]

In order to solve the conventional problems, the present invention has a structure in which a plurality of optical fibers are freely housed in a LAP sheath pipe, a reinforcing and buffering O jacket is provided around the outer periphery of the LAP sheath pipe, and each of the optical fibers is It is characterized by having colored dots and a band-like mark.

[Effect]

Since the optical cable u of the present invention has a structure in which a plurality of optical fibers are freely housed in a LAP sheath pipe and a jacket is applied to the outer periphery, it is possible to install the optical cable by peeling off the jacket. ), the optical fiber inside the LAP sheath pipe can be easily taken out without cutting, and each optical fiber is equipped with individually colored dots, bands, and zero marks on the outer surface. Therefore, it is possible to identify individual optical fibers and measure the length of the original fiber when connecting it to an external terminal device by irradiating the original fiber from any position on the optical fiber. Examples will be described below based on the drawings.

〔Example〕

FIG. 1 is a cross-sectional structural diagram of a first embodiment of the present invention. 1
2 is an optical fiber, and 2 is a plurality of optical fibers, 6 in this example. 1: A LAP sheath pipe that can be stored freely, that is, in pieces, and 9 tensile strength materials attached vertically to the outer periphery of the 5-wire LAP sheath pipe 2. as - Kevra as an example,
4 is a corrugated steel tape, and 5 is a polyethylene sheath. The corrugated steel tape 4 and the polyethylene sheath 5 are formed on the outer cover, which together with the capping material as a tensile strength material, maintains crush resistance and bendability and functions as a buffer layer against external pressure. In the structure of the first embodiment, six optical fibers 1 of Q, 25 and 1 diameter are butted together with laminated aluminum tape with a thickness of about 125, and freely stored in pieces in an fc LAP sheath pipe. , 1 ton of Kepra fiber (3Q, 000 denier) on the outer periphery of the LAP sheath pipe! A corrugated steel tape not coated with an adhesive resin is vertically attached to the outer circumference of the steel with a thickness of approximately cL15tM and molded in a cylindrical shape, and the weight part is glued to the steel.
An optical cable with an outer diameter of approximately 1240 mm and a length of 1000 seconds was fabricated using a polyethylene sheath with a thickness of fIwl and thick using a batch extrusion method.9. Applying a lateral pressure load to the optical cable 1sCZ) sample of this example using a metal plate with a side width of 50 threshold.
Ku. The next optical fiber is housed in the LAP sheath pipe.
A folded connection was used to receive light from the center, and when light was incident on one end and the transmission characteristics were measured using the other end, results were obtained that were ±OdE compared to when no load was applied. As a result, no influence of lateral pressure was observed on the transmission characteristics of the optical fiber9.

FIG. 2 is a cross-sectional structural diagram of a second embodiment of the present invention. The same reference numerals as in FIG. 1 indicate the same parts. In this embodiment, six optical fibers 1 having the same structure as the first embodiment are housed, and Kevlar 5 i as a tensile strength material is installed around the outer periphery of a nine-LAP sheath pipe 2.
This is an example in which LAP tape 6 is longitudinally attached and molded into a cylindrical shape on the outer circumference of a 30,000 denier wrapped outer circumference, and a polyethylene sheath 5 is applied on it to a thickness of about 1.5 mm by extrusion method.
An optical cable with a length of 1.000 m was fabricated as in Example 1. A lateral pressure load of 300 kg and 150 inertia was applied to the optical cable of this example in the same manner as in the first example, and the transmission characteristics were measured under the same conditions as in the first example. A result of ±OdB was obtained. As a result, no influence of lateral pressure was observed on the transmission characteristics of the optical fiber.

FIG. 3 is a cross-sectional structural diagram of a fifth embodiment of the present invention. The same reference numerals as in FIG. 1 indicate the same parts. This embodiment is a LAP that houses 1t-6 optical fibers with the same structure as the first embodiment.
A LAP tape is further longitudinally attached to the outer periphery of the sheath pipe 2 to form a cylindrical shape, and on top of that, a steel wire or FRP as a tensile strength material is embedded longitudinally in a 7t'' 2-strip polyethylene 7-thickness, and from 9 polyethylene/sheath 5. Approximately 2.2
In this example, an optical cable with a length of 1000 m, which is the same as in the first example, was manufactured using an extrusion method to a thickness of 1.0 mm. For the optical cable of this example, 300
When a lateral pressure load of 150 kg was applied and the transmission characteristics were measured under the same conditions as in the first example, results of ±OdE were obtained compared to when no lateral pressure load was applied. As a result, no influence of lateral pressure was observed on the transmission characteristics of the optical fiber.

In addition to the above-mentioned examples, the outer sheath applied to the outer periphery of Kevushi fiber, steel wire, or FEP t-LAP sheath pipe as a tensile strength material is wrapped or attached vertically, and in addition to the above-mentioned examples, the outer sheath is made of linear low-density fiber with a thickness of 1 cotton or more. Polyethylene (linear low density polyethylene, hereinafter abbreviated as n-LDPE), or corrugated steel tape and E-
A similar effect can be obtained by applying this to the jacket structure m1 made of LDPE or LAP tape and A-LDPE, which is included in the aspect of the present invention.

Furthermore, the present invention makes it possible to identify the optical fibers by applying colored dots or band-like marks at regular intervals on the outer surface of the optical fibers that are freely stored in pieces in the LAP sheath pipe. This makes it possible to easily measure the coupling position length of an optical fiber when coupling light with an external terminal device at an intermediate point of the optical fiber.

〔Effect of the invention〕

As explained above, the present invention provides a plurality of optical fibers k L
It can be freely stored in pieces inside the AP sheath spike,
Since the LAP sheath pipe has a structure in which tensile strength material is distributed and coated around the outer periphery of the LAP sheath pipe, the optical fiber can be taken out without cutting by peeling off the sheath, and it can also be stored inside the LAP sheath pipe. On the outer periphery of each of the multiple optical fibers, colored dots t are placed at equal intervals.
By attaching a band-shaped mark to the optical fiber, it is possible to easily identify each original fiber and measure the desired length position of the optical fiber. A local area network that optically couples external terminal equipment at any point in the middle of the fiber.
1 4 15 7F% fi llllIc If
J-1-i/lk IIn $ J-+ 1
The effect is noticeable when applied to Ji/-No. In addition, the optical cable according to the present invention completely compensates for the tensile strength of the optical fiber freely stored in the LAP sheath pipe by arranging a tensile strength material such as Kepra fiber, steel wire, or FRP on the outer periphery of the LAP sheath pipe. By applying an overcoat of %LAP tape or/and fl,-LDPE, for example by extrusion? ), the aluminum and glass of the LAP sheath pipe are fused together to improve mechanical strength, have excellent flexibility, and further reduce the diameter.
The ease of handling also makes it more effective for dogs.

[Brief explanation of drawings]

1, K2, and 3 respectively show the first part of the optical fiber cable according to the present invention. FIG. 4 is a cross-sectional structural diagram of the second and fifth embodiments. DESCRIPTION OF SYMBOLS 1... Optical fiber, 2... LAP sheath vig, 5... Kevlar, 4... Corkated steel tape, 5... Polyethylene sheath, 6... LAP tape, 7... Tensile strength material patent Applicant Sumitomo Electric Industries Co., Ltd. Agent Patent Attorney Tamamushi Kugobe Cross-sectional structural diagram of the first embodiment of the present invention Figure 1 Cross-sectional structural diagram of the second embodiment of the present invention '1s2 Figure 6 of the present invention Cross-sectional structure drawing of Example 3

Claims (5)

[Claims] (1) In an optical fiber cable comprising a plurality of optical fibers having colored dots or band-like marks on the outer surface for identification and length measurement, the plurality of optical fibers can be freely housed within a LAP sheath pipe. An optical fiber cable characterized in that the LAP sheath pipe is provided with a reinforcing/buffering jacket around the outer periphery of the LAP sheath pipe. (2) The reinforcing/buffering jacket is characterized in that it is made by applying a plastic sauce to a corrugated steel tape that is vertically wrapped in a cylindrical shape around the outer periphery of Kepra fiber that is vertically wrapped or wrapped around the LAP sheath pipe. An optical fiber cable according to claim 1. (3) The reinforcing/buffering outer sheath is made of LAP fibers attached to the outer periphery of the Keppra fibers that are longitudinally attached or wrapped around the LAP sheath pipe.
The optical fiber cable according to claim 1, characterized in that the optical fiber cable is provided with a sheath. (4) The reinforcing/buffering jacket is formed by forming a LAP tape on the LAP sheath pipe vertically in a cylindrical shape, and then extruding it around the outer periphery of the LAP tape, which is then vertically attached or wrapped around the LAP tape, such as steel wire and FRP. The optical fiber cable according to claim 1, characterized in that it is made of a plastic source. (5) The optical fiber is coated with a transparent resin that allows light to pass therethrough. fiber optic cable.