JP2009244589A - Optical fiber cable - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve intermediate branching of optical fiber cable in a narrow space requiring no closures by easy work. <P>SOLUTION: An optical fiber cable 100 includes a cable support line part 35 having a tension member 31 covered with a sheath 33 and optical element parts 43 suspended at prescribed intervals along the cable support line part 35 through support parts 37 and having a plurality of optical fiber core wires 39 coated with the cable sheaths 41, and in each optical element part 43, cable sheaths 41 and 41 covering adjacent optical fiber core wires 39 are intermittently connected in a lengthwise direction. The cable sheaths 41 covering adjacent coated optical fibers 39 can be intermittently connected in the lengthwise direction by forming slits 45 and connection parts 47 alternately. Preferably, support parts 37 from which optical element parts 43 are suspended and connection parts 47 connecting the cable sheaths 41 are provided in the same phase in the lengthwise direction of the cable. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical fiber cable that is installed in an aerial and is used to drop an optical fiber core wire into a general subscriber's house, and in particular, an intermediate branch in a small space that does not require a closure can be realized by an easy operation. Relates to improved technology.

  2. Description of the Related Art Conventionally, an optical fiber drop cable (outdoor line) that is laid over an electric pole and is suitable for drawing an optical fiber cable core to a subscriber's house such as a general house has been used. For example, in the optical fiber drop cable 1 disclosed in Patent Document 1, as shown in FIG. 4, an optical fiber single core wire or an optical fiber tape core wire (optical fiber core wire) 5 is embedded in a cable sheath 3. A long optical element portion 7 and a long cable support wire portion 11 that is continuously or intermittently fixed integrally via a neck portion 9 constricted in parallel to the optical element portion 7. Yes.

  The optical element unit 7 includes, for example, at least a pair of elongate first tensile strength members 13 arranged in parallel on both sides of the optical fiber core wire 5, and these include polyethylene, polyvinyl chloride (PVC) A long optical element portion 7 is formed by coating with a cable sheath 3 of a thermoplastic resin such as).

As shown in FIG. 5, in the optical fiber drop cable 1, a required optical element portion 7 is branched at a cable branch box (cable closure) 17 for each drop point of each power pole 15, and a drop cable 19 is used for a general household or It is withdrawn to the office. In addition, since the neck portion 9 is provided, the optical element portion 7 can be easily separated from the cable support wire portion 11 for indoor wiring. In FIG. 5, 21 indicates a trunk cable.
JP 2003-90942 A

However, the above-described conventional optical fiber drop cable 1 tears the cable sheath 3 of the optical element portion 7 at the intermediate branch to take out the optical fiber core 5 inside, so that the exposed optical fiber core 5 is protected. Closure 17 was required. In addition, it is necessary to secure an installation space for the closure 17, and a necessary space for performing an intermediate branch is required. Further, when the optical element portion 7 is torn, a large number of optical fiber core wires 5 jump out at a time and are scattered, and there is a problem such as poor workability in the closure 17.
The present invention has been made in view of the above situation, and it is an object of the present invention to provide an optical fiber cable that can realize an intermediate branch in a small space without a closure by an easy operation.

The above object of the present invention is achieved by the following configuration.
(1) A cable support line portion in which a tensile body is covered with a sheath, and an optical element portion in which a plurality of optical fiber core wires are covered with a cable sheath and suspended at predetermined intervals along the cable support line portion via the support portion. An optical fiber cable consisting of
The optical element section is an optical fiber cable in which cable sheaths covering adjacent optical fiber core wires are intermittently connected in the longitudinal direction.

  According to this optical fiber cable, since the connecting portion is cut, other optical fiber cores are not separated and exposed, and a desired optical fiber core can be easily separated. Since each optical fiber core wire is protected by a weather-resistant cable sheath, it can be connected to a drop cable using a jacket holding connector, and a closure is not required. Moreover, since each is coat | covered with a cable sheath, it becomes possible to use a single optical fiber core wire for indoor wiring as it is.

(2) The optical fiber according to (1), wherein the cable sheath covering the adjacent optical fiber cores is intermittently connected in the longitudinal direction by alternately forming slits and connecting portions. cable.

  According to this optical fiber cable, even in a structure in which a plurality of optical fiber cores are covered with an integral cable sheath, the cable sheaths of adjacent optical fiber core wires are intermittently connected by the slit and the connecting portion, The intermediate branching of the optical fiber core is easy.

(3) Each of the optical fiber core wires is individually covered with the cable sheath,
The optical fiber cable according to (1), wherein the cable sheaths covering the adjacent optical fiber core wires are intermittently connected in the longitudinal direction via a connecting portion.

  According to this optical fiber cable, the optical fiber core wires that are individually coated and have weather resistance independently are intermittently connected to the cable sheath at a connecting portion that is integral with or separate from the cable sheath. The intermediate branching of the optical fiber core becomes easier. In addition, since the individually coated single-core optical fiber is branched in the middle, it is possible to cope with indoor wiring.

(4) Any one of (1) to (3), wherein the support part for suspending the optical element part and the connecting part for connecting the cable sheath are provided in the same phase in the cable longitudinal direction. Or one fiber optic cable.

  According to this optical fiber cable, even when the connecting portion of the cable sheath is disposed so as to coincide with the hanging direction of the support portion and the upper optical fiber core wire is branched and cut, the connecting portion is interposed through the connecting portion. Thus, all the optical fiber core wires in the lower stage are supported by the support portion, and the support structure is not eliminated.

(5) The optical fiber cable according to (4), wherein the length of the optical element portion between the connecting portions is longer than the length of the cable support line portion between the support portions.

  According to this optical fiber cable, even if the linear expansion coefficients of the cable support line part and the optical element part are different, the optical element part has an extra length with respect to the cable support line part. A tension | tensile_strength does not act on an optical element part by a line part, but can protect an optical fiber core wire from the external force of an axial direction.

  According to the optical fiber cable of the present invention, the optical element portion is suspended at predetermined intervals along the cable support line portion via the support portion, and the optical element portion covers the adjacent optical fiber core wire. Are intermittently connected in the longitudinal direction, so that the optical fiber cores can be easily separated into single cores by cutting the connection part, and each optical fiber core is protected by a weather resistant cable sheath. Since it can be connected to the drop cable using only the jacket grip connector, no closure is required. As a result, an intermediate branch in a small space that does not require a closure can be realized with an easy operation.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of an optical fiber cable according to the invention will be described with reference to the drawings.
FIG. 1 is a perspective view of an optical fiber cable according to the present invention, and FIG. 2 is a perspective view of a modified example in which phases of a support portion and a connecting portion are different.
The optical fiber cable 100 includes a cable support wire portion 35 in which a tensile body 31 is covered with a sheath 33, and a plurality of optical fiber core wires 39 that are suspended along the cable support wire portion 35 via a support portion 37 at predetermined intervals. The optical element portion 43 is covered with a cable sheath 41.

  As the strength member 31, for example, a steel wire as a metal wire, an aramid fiber that is a non-conductive strength fiber, an engineering plastic (engineering plastic), or the like is used.

  As the thermoplastic resin constituting the sheath 33, the support portion 37, and the cable sheath 41, a thermoplastic resin such as polyethylene or polyvinyl chloride is used. These are covered to form a long optical fiber cable 100 including the cable support line portion 35, the support portion 37, and the optical element portion 43. The thermoplastic resin may contain a flame retardant or a different colorant for each optical fiber core wire 39. For example, the surface of the optical element portion 43 is colored in different colors such as red, green, purple, yellow,... The fiber core wires 39 can be distinguished from each other.

  The shape of the cable sheath 41 covering the cable support wire portion 35 and the optical fiber core wire 39, the shape of the optical element portion 43, and the like are not particularly limited. For example, in the illustrated example, the sheath 33 and the cable sheath 41 are used. Each of these has a substantially circular cross section, but may have an elliptical cross section or a rectangular cross section.

  Although not shown, it is preferable that a tensile strength fiber layer is vertically provided around the optical fiber core wire 39. As the tensile strength fiber, aramid fiber such as poly-p-phenylene terephthalamide fiber, polyarylate fiber, polyparaphenylene benzbisoxazole fiber, polyester fiber such as polyethylene terephthalate fiber, nylon fiber, and the like can be used.

  In the optical element portion 43, the cable sheaths 41, 41 covering the adjacent optical fiber core wires 39, 39 are intermittently connected in the longitudinal direction. In the illustrated example, cable sheaths 41 and 41 covering adjacent optical fiber cores 39 and 39 are intermittently connected in the longitudinal direction by alternately forming slits 45 and connecting portions 47. The sheath 33, the support portion 37, the cable sheath 41, and the connecting portion 47 may be integrally formed of the same material at the same time. After the sheath 33 and the cable sheath 41 are separately formed, they are connected by the support portion 37. May be.

  As described above, in the optical fiber cable 100, a plurality of optical fiber cores 39 are covered with the integral cable sheath 41, and the cable sheaths 41 and 41 of the adjacent optical fiber cores 39 and 39 are connected to the slit 45 and the connecting portion 47. Thus, the intermediate branch of the single optical fiber core wire 39 can be easily performed.

  As specific dimensions of each part, the diameter φ of the cable sheath 41 is about 1 to 2 mm, the length L between adjacent support parts 37 is about 40 to 70 cm, and the length S of the slit 45 is about 30 to 50 cm. The length A of the support part 37 and the connecting part 47 is formed to be about 10 to 20 cm.

  The support part 37 for suspending the optical element part 43 and the connecting part 47 for connecting the cable sheath 41 are provided in the same phase in the cable longitudinal direction as shown in the figure. Thereby, even when each connecting portion 47 of the cable sheath 41 is arranged in the hanging direction of each supporting portion 37 and the upper optical fiber core wire 39 is branched and cut at the midway portion 49, All the optical fiber core wires 39 in the lower stage are supported by the support part 37 via the connecting part 47 of that stage, and the support structure is not eliminated.

  In the optical fiber cable 100 according to the present embodiment, the support portion 37 and the connecting portion 47 are provided in the same phase in the cable longitudinal direction. However, as shown in FIG. And the optical fiber cable 100A in which the slits 45 are provided in the same phase in the cable longitudinal direction.

FIG. 3 is a perspective view of a modification in which optical fiber core wires are individually coated.
In the optical fiber cable 100 according to the above embodiment, each optical fiber core wire 39 is integrally covered with a cable sheath 41. However, as shown in FIG. Each may be an optical fiber cable 100 </ b> B individually covered with a cable sheath 41. In this configuration, the cable sheaths 41, 41 covering the adjacent optical fiber cores 39, 39 are intermittently connected in the longitudinal direction via the connecting portion 47A to constitute the optical element portion 43A. The connecting portion 47A may be integrally formed of the same material as the cable sheath 41 at the same time, or may be formed of another member such as the same material or an adhesive after each of the cable sheaths 41 is formed separately. .

  According to the optical fiber cable 100B, the optical fiber core wires 39 that are individually coated and have independent weather resistance are intermittently connected to the cable sheath 41 by a connecting portion 47A that is integral with or separate from the cable sheath 41. The intermediate branching of the optical fiber core wire 39 of the core is further facilitated. Further, since the individually coated single-core optical fiber core 39 is branched in the middle, it can be used as a drop cable. The connecting portion 47A includes a pair of tearing notches 51 on both side surfaces, so that the desired optical fiber core wire 39 can be easily released by tearing the connecting portion 47A starting from the tearing notches 51. be able to.

  Further, in the optical fiber cable 100, the length J (see FIG. 1) of the optical element portion 43 between the connecting portions 47 and 47 is set to be longer than the length L of the cable support wire portion 35 between the support portions 37 and 37. Can do. As a result, even if the linear expansion coefficients of the cable support wire portion 35 and the optical element portion 43 are different, the optical element portion 43 has an extra length with respect to the cable support wire portion 35, so that the cable support wire portion 35 has expanded. The tension is not applied to the optical element portion 43 by the cable support wire portion 35, and the optical fiber core wire 39 can be protected from the external force in the axial direction.

  In the optical fiber cable 100 configured as described above, the middle part 49 of the desired optical fiber core wire 39 is cut by the slit 45 at the drop point of the utility pole. A jacket grip connector (not shown) is connected to the cut optical fiber core wire 39. When a predetermined length is required for the branched optical fiber 39, the connecting portion 47 on the downstream side in the light propagation direction is sequentially cut as necessary to ensure the required length.

  A mating connector connected to a drop cable (not shown) is coupled to the jacket holding connector. The drop cable is fixed to an outdoor line clamp (not shown) of the utility pole, and the other end is fixed to a part of the house via the clamp and connected to an indoor OE converter or termination box. In the optical fiber cable 100, a drop cable can be connected to the intermediate optical fiber core wire 39 via a jacket holding connector. However, the single-core optical fiber core wire 39 covered with the cable sheath 41 is used as it is as a drop cable. May be.

  As described above, in the optical fiber cable 100, the connecting portion 47 is cut, so that the other optical fiber cores 39 are not separated and exposed, and the desired optical fiber cores 39 can be easily separated from each other. It becomes possible. Since each optical fiber core wire 39 is protected by a cable sheath 41 having weather resistance, it is possible to connect with a drop cable using only a jacket holding connector, and no closure is required. Moreover, since each is coat | covered with the cable sheath 41, it becomes possible to use the single-core optical fiber core wire 39 as a dropping cable as it is.

  Therefore, according to the optical fiber cable 100 having the above configuration, the optical element portion 43 is suspended at predetermined intervals along the cable support line portion 35 via the support portion 37, and the optical element portion 43 is adjacent to the optical fiber core. Since the cable sheath 41 covering the wire 39 is intermittently connected in the longitudinal direction, the optical fiber core wire 39 can be easily separated into a single core by cutting the connecting portion 47, and the individual optical fiber core wires can be separated. 39 is protected by a weather-resistant cable sheath 41 and can be connected to the drop cable using only the jacket gripping connector, so that no closure is required. As a result, an intermediate branch in a small space that does not require a closure can be realized with an easy operation.

1 is a perspective view of an optical fiber cable according to the present invention. It is a perspective view of the modification from which the phase of a support part and a connection part differs. It is a perspective view of the modification by which the optical fiber core wire was coat | covered separately. It is a perspective view of the conventional optical fiber cable. It is the schematic diagram showing the wiring condition using the conventional optical drop cable.

Explanation of symbols

DESCRIPTION OF SYMBOLS 31 Strength body 33 Sheath 35 Cable support line part 37 Support part 39 Optical fiber core wire 41 Cable sheath 43 Optical element part 45 Slit 47 Connection part 100 Optical fiber cable J Length of the optical element part between connection parts L Between support parts Cable support line length

Claims (5)

A cable support line portion in which a tensile body is covered with a sheath, and an optical element portion that is suspended along the cable support line portion via a support portion at predetermined intervals and covers a plurality of optical fiber core wires with a cable sheath. An optical fiber cable,
The optical element portion is an optical fiber cable in which cable sheaths covering adjacent optical fiber core wires are intermittently connected in the longitudinal direction.   The optical fiber cable according to claim 1, wherein the cable sheath covering the adjacent optical fiber cores is intermittently connected in the longitudinal direction by alternately forming slits and connecting portions. Each of the optical fiber cores is individually coated with the cable sheath,
The optical fiber cable according to claim 1, wherein the cable sheaths covering the adjacent optical fiber core wires are intermittently connected in the longitudinal direction via a connecting portion.   The support portion for suspending the optical element portion and the connecting portion for connecting the cable sheath are provided in the same phase in the cable longitudinal direction. The optical fiber cable described.   5. The optical fiber cable according to claim 4, wherein the length of the optical element portion between the connecting portions is longer than the length of the cable support line portion between the support portions.

Images