JP2001124964A - Indoor opticla fiber cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an indoor optical fiber cable having satisfactory handleability, capable of sufficiently securing tensile strength, withstanding various kinds of loads and obtaining smaller cable outer diameter and bending diameter as an indoor optical cable, and occupying the intermediate area of conventional cord gathered type cable and optical fiber cord. SOLUTION: Two coated optical fiber tapes (2), for which two optical fibers (1) are arranged side by side in a single line and integrally formed are gathered, a pipe-like reinforcing body (4) for which the plastic material of high mechanical strength is formed into a pipe shape is provided on the outer periphery of a buffer material (3), disposed around the coated optical fiber tapes (2) and a cable core (5) is attained. The two cable cores (5) are arranged side by side in a single line and integrally formed by a sheath (7), together with one tension member (6), and an indoor optical fiber cable (10) is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber cable. More specifically, the present invention relates to an indoor optical fiber cable used when connecting indoor information processing devices.

[0002]

2. Description of the Related Art Conventionally, as an optical fiber cable laid indoors (hereinafter abbreviated as an indoor optical fiber cable or an indoor optical cable), for example, an optical fiber cord (34) is assembled as shown in FIG. An assembled cable (40) is used. In some cases, only the optical fiber cord (34) is used as an indoor optical cable. The optical fiber cord (34) constituting the cord assembly type cable (40) is provided with a tensile strength member (32) and a polyvinyl chloride resin (PVC) coating (3) on the outer periphery of the optical fiber core wire (31).
3), for example, the outer diameter is 2.0-3.
0 mm. Further, the cord assembly type cable (40)
The tension member (36) consisting of four optical fiber cords (34), two polyethylene interpositions (35), and an FRP rod of, for example, 3 mmφ is attached to the tension member.
(36) are arranged as shown in the figure, and these arrays are pressed and wrapped with a resin tape (37), and then PVC
Is provided, and the outer diameter thereof is, for example, 11 to 12 mm.
The structure is as follows.

[0003]

An indoor optical cable is used mainly for connecting information processing devices between indoor rooms, and is usually provided with optical connectors attached to both ends or one end. used. The main laying place is
Above the floor, below the floor, or ceiling. For this reason, as the load applied to the optical cable, in addition to the tension at the time of laying, it is conceivable that the optical cable is stepped on, an object falls, or a strong bending is applied. Therefore, it is necessary to provide an optical cable that can withstand these loads.

[0004] The optical fiber cord (34) has a problem that the tensile strength is weak because there is no tension member. In addition, since the sheath thickness is thin, for example, in the case of a long laying exceeding 50 m, it has to be sideways. However, there is a problem in that the strength is insufficient against the impact of the object, and also weak against the impact of a falling object. Also, the cord-assembled cable (40) has a greater strength against impacts from the side and impacts from falling objects than the optical fiber cord (34), but has a large outer diameter, and has a large number of optical fibers. However, there is a problem that the occupied area increases when the cable is laid. Further, since the optical fiber cord (34) and the cord assembly type cable (40) have a round cross-sectional shape, there is a problem that the optical fiber cord (34) rolls, particularly when laid on the floor.

The present invention has been made to solve the above-mentioned various problems of the prior art, and requires a tensile strength as an indoor optical cable occupying an intermediate region between a conventional cord-assembled cable and an optical fiber cord. An object of the present invention is to provide an indoor optical fiber cable which is sufficiently secured, can withstand various loads, has a smaller cable outer diameter and a smaller bending diameter, and has good handleability.

[0006]

According to a first aspect of the present invention, a plurality of optical fiber cores (2) are formed by arranging a plurality of optical fiber wires (1) in a horizontal line and integrally forming the optical fiber cores (2).
Buffer material (3) arranged around these multiple optical fiber ribbons
A pipe-shaped reinforcement (4) made of a plastic material with high mechanical strength formed in a pipe shape
An indoor optical fiber cable (5) in which a plurality of the cable cores (5) are arranged in a horizontal row and integrally formed with a sheath (7) together with one or more tension members (6). Hereinafter, it is abbreviated as an indoor optical cable).

[0007] The optical fiber (1) is an SM type,
Either GI type quartz fiber can be used. Further, instead of the quartz fiber, a nylon core wire in which a quartz fiber is coated with nylon can be used. in this case,
In addition to the SM-type and GI-type quartz fibers, PCF (plastic clad quartz fiber) or plastic fiber can be applied. Also said optical tape core wire
As (2), two or four cores are generally used, but are not particularly limited. As the cushioning material (3), aramid fiber, for example, Kevlar (trade name of DuPont, U.S.A.) and, if necessary, a gel compound (e.g., jelly) are used. When the aramid fiber is used, it can serve as both a cushioning material and a tensile strength material. As the plastic material having high mechanical strength used for the pipe-shaped reinforcement (4), for example, high-density polyethylene resin or the like is used. As the tension member (6),
For example, a steel wire, FRP, or the like is used. As the sheath (7), for example, PVC or the like is used.

The indoor optical cable according to the first aspect uses an optical fiber ribbon (2) as an optical fiber housed in a pipe-shaped reinforcing member (4), and is mounted at a high density. The number of cores of the optical fiber can be significantly increased, and the outer diameter of the cable can be reduced. In addition, since the optical tape core wire (2) is protected by a plastic material with high mechanical strength, for example, by a pipe-shaped reinforcing body (4) formed in a pipe shape by extrusion, it is resistant to impact from the side. And effective. In addition, the shock applied to the optical fiber ribbon can be reduced by the cushioning material (3). In addition, since the optical fiber ribbon (2) is used, the outer diameter of the cable can be made smaller and smaller than the number of fibers used. In addition, most of the tension and compression in the longitudinal direction of the cable generated during the installation of the optical cable are covered by the sheath (7) and the pipe-shaped reinforcement (4).
Can be borne. Also, tension member (6)
Is provided, one or more of them can bear a tension or a compressive force in the cable longitudinal direction. Also,
The arrangement position of the tension member (6) in the sheath (7) is not particularly limited, but may be provided, for example, at an intermediate portion or an outer portion of a plurality of cable cores (5) arranged in a horizontal line. Is preferred. Further, the pipe-shaped reinforcement (4),
The material of the tension member (6) and the sheath (7) does not break or crack even if strong bending is applied, so that sufficient performance is maintained even if bending of about 10 times the cable outer diameter is applied. It is possible.

According to a second aspect of the present invention, there is provided an indoor optical cable in which the optical fiber ribbon (2) is an integrally molded product made of UV resin (u). In the indoor optical cable according to the second aspect, since the optical tape core wire (2) is an integrally molded product made of UV resin (u), multi-core batch installation is possible, and the number of installed cables can be reduced. Becomes

According to a third aspect of the present invention, there is provided an indoor optical cable in which the tension member (6) is made of a non-metallic material. As the non-metallic material, FR
P, aramid fiber such as Kevlar (trade name of DuPont, USA), or polyarylate fiber such as Vectran (trade name of Kuraray) can be used. The third above
The indoor optical cable according to the above aspect, wherein the tension member
By making (6) a non-metallic material, a non-metallic cable having no conductor in the cable structure can be obtained. Particularly, it is suitable for use in an environment where insulation is required, such as near a power line.

[0011] As a fourth aspect, the present invention relates to the above-mentioned sheath.
(7) The indoor optical cable is made of a halogen-free material or a lead-free material. In the indoor optical cable according to the fourth aspect, if a non-halogen material such as a flame-retardant polyethylene resin is used as the material of the sheath (7), generation of harmful gas (halogen gas, etc.) at the time of fire or the like can be prevented.
Suitable for indoor use. If a lead-free material such as lead-free PVC is used as the material of the sheath (7), it is possible to cope with an environment-friendly cable.

According to a fifth aspect of the present invention, there is provided an indoor optical cable, wherein the indoor optical fiber cable has a flat cross section. The indoor optical cable according to the fifth aspect,
By making the cross-sectional shape flat, for example, rectangular,
The cable is less likely to be twisted, and bending stress is less likely to be applied to the optical fiber ribbon (2). In addition, when laying on a floor or the like, it is possible to prevent the cable from rolling, and to efficiently lay the cable.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The contents of the present invention will be described below in more detail with reference to an embodiment shown in the drawings. Note that the present invention is not limited by this. FIG. 1 is a sectional view showing a first embodiment of the indoor optical fiber cable of the present invention. FIG. 2 is a cross-sectional view showing a second embodiment of the indoor optical fiber cable of the present invention. In these figures, 1 is an optical fiber strand, 2 is an optical fiber ribbon (two-core optical fiber ribbon), 3 is a cushioning material, 4 is a pipe-shaped reinforcement, 5 is a cable core, 6 is a tension member, 7 Is the sheath, 1
Reference numerals 0 and 20 denote indoor optical fiber cables, and u denotes a UV resin (tape binder).

Embodiment 1 An indoor optical cable according to Embodiment 1 of the present invention will be described with reference to FIG. First, as an optical fiber (1), φ
Two 250 μm UV strands were arranged in a horizontal line, and integrally formed into a ribbon shape using a UV resin (u) as a tape binder to obtain an optical tape core (two-core optical tape) (2).
Next, two optical tape cores (2) were assembled, and a Kevlar was arranged as a cushioning material (3) around the two optical tape cores (2, 2). Next, a high-density polyethylene resin of a plastic material having high mechanical strength was melt-extruded into a pipe shape on the outer periphery thereof to provide a pipe-shaped reinforcing body (4), thereby forming a cable core (5). Next, the two cable cores (5) are arranged in a horizontal line, and the two cable cores (5) are arranged.
A steel wire having a diameter of about 0.7 mm is disposed as a tension member (6) at the intermediate position of (5), and PVC is melt-extruded into a rectangular shape to provide a sheath (7), and an indoor optical cable (10) is provided. Manufactured. When the sheath (7) is made of PVC, the sheath color can be set to a color such as red, blue, yellow, or green in addition to black. For example, the sheath color is different for each system series. This can prevent erroneous installation.
The outer diameter of the optical fiber ribbon (2) is, for example, 0.1 mm on the short side.
6 mm, long side 1.1 mm. The outer diameter of the pipe-shaped reinforcement (4) is, for example, 4 mm. The outside diameter of the indoor optical fiber cable (10) is, for example, a short diameter of 6 mm and a long diameter of 11 mm.

Embodiment 2 An indoor optical cable according to Embodiment 2 of the present invention will be described with reference to FIG. The same optical fiber ribbon as in the first embodiment.
(2), and the optical fiber ribbon (2,
Kevlar was arranged around 2) as a cushioning material (3). next,
A high-density polyethylene resin was melt-extruded into a pipe shape on the outer periphery thereof to provide a pipe-shaped reinforcing body (4), thereby forming a cable core (5). Next, the two cable cores (5) are arranged side by side in a row, and the two cable cores (5) are arranged side by side.
Outside the (5), as a tension member (6), a thickness of 127
One 0 dtex kevlar was provided, and a flame-retardant polyethylene resin was melt-extruded into a rectangular shape to provide a sheath (7), thereby producing a non-metallic indoor optical cable (20). The outer diameter of the optical cable (20) of the second embodiment is substantially the same as the outer diameter of the optical cable (10) of the first embodiment.

The indoor optical cables obtained in the first and second embodiments have sufficient and sufficient tensile strength, withstand various loads, and have smaller cable outer diameters and bending diameters. In addition, it was possible to prevent the cable from rolling, and it was possible to efficiently lay the cable when laying it on the floor or the like. Further, the indoor optical cable obtained in the second embodiment can be used as an indoor optical cable having a non-metallic structure and an environment-friendly optical cable.

[0017]

According to the indoor optical cable of the present invention, the tensile strength is secured, the finished outer diameter of the cable can be reduced, and the minimum bending diameter can be reduced. In addition, a pipe-shaped reinforcing member is adopted as a structure for protecting the load from the side, and the optical tape core wire is housed in the reinforcing member, so that it is protected from a considerable external pressure. Further, by using an optical fiber ribbon as the shape of the optical fiber housed in the pipe-shaped reinforcing member, the outer diameter of the cable can be reduced with respect to the number of mounting cores, and the size can be reduced. Therefore, high-density mounting is possible, multi-core batch installation is possible, and the number of installed cables can be reduced.

When the tension member is made of a non-metallic material, it is possible to use a non-metallic cable having no conductor in the cable structure, which is suitable for use in an environment where insulation is required. In addition, PVC is generally used as the sheath material from the viewpoint of bendability and flame retardancy. However, when a non-halogen material is used, it is possible to prevent the generation of halogen gas at the time of fire, etc. It became more suitable for use. When lead-free material is used for the sheath material, it is possible to respond to environmentally conscious cables. Further, when the optical cable of the present invention has a flat cross-sectional shape, the cable is hardly twisted, so that bending stress is not easily applied to the optical tape core wire, and when laid on the floor or the like, the cable can be prevented from rolling, and the efficiency can be improved. Can now be wired. Therefore, the present invention has an extremely large effect of contributing to industry.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of an indoor optical fiber cable of the present invention.

FIG. 2 is a sectional view showing a second embodiment of the indoor optical fiber cable of the present invention.

FIG. 3 is a sectional view showing an example of a conventional indoor optical fiber cable.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical fiber wire 2 Optical tape core wire (2 core optical tape cores) 3 Buffer material 4 Pipe-shaped reinforcement body 5 Cable core 6 Tension member 7 Sheath 10, 20 Indoor optical fiber cable u UV resin (tape binder)

Claims (5)

[Claims] 1. A plurality of optical fiber ribbons which are arranged in a row and a plurality of optical fiber ribbons are integrally formed, and a plurality of optical fiber ribbons are formed around an outer periphery of a cushioning member provided around the plurality of optical fiber ribbons. A pipe-shaped reinforcing member formed of a plastic resin having high mechanical strength in the form of a pipe is provided as a cable core, and a plurality of the cable cores are arranged in a horizontal row.
An indoor optical fiber cable, which is integrally formed with a sheath together with one or more tension members. 2. The indoor optical fiber cable according to claim 1, wherein the optical fiber ribbon is an integrally molded product made of a UV resin. 3. The indoor optical fiber cable according to claim 1, wherein the tension member is made of a non-metallic material. 4. A material according to claim 1, wherein said sheath is made of a halogen-free material or a lead-free material.
Or the indoor optical fiber cable according to 3. 5. The indoor optical fiber cable according to claim 1, wherein the indoor optical fiber cable has a flat cross section.