JP6027487B2 - Optical fiber cable intermediate branching jig and optical fiber cable intermediate branching method - Google Patents

Description

  The present invention relates to an optical fiber cable intermediate branching jig and an optical fiber cable intermediate branching method.

  Conventionally, in an intermediate branching operation of an optical fiber cable, it is required to branch easily while suppressing occurrence of optical loss fluctuation. In order to satisfy this requirement, an optical fiber cable in which tensile strength members are arranged in parallel on both sides of the optical fiber core and are collectively covered with a cable jacket, on both sides of the optical fiber core wire on the side where the tensile strength member is not disposed. A structure in which a peeling tape (intervening tape) is provided on the part is known (see, for example, Patent Documents 1 and 2). At the time of intermediate branching, an optical fiber core wire in the optical fiber cable is taken out by making a notch reaching the peeling tape from the side surface of the optical fiber cable in the longitudinal direction of the cable.

JP 2012-088500 A JP 2008-070601 A

  However, in the optical fiber cables described in Patent Documents 1 and 2, it is necessary to mount a peeling tape in the optical fiber cable. Therefore, it takes time and labor to separate or cut the peeling tape during intermediate branching, and workability may be deteriorated.

  An object of the present invention is to provide an optical fiber cable that can suppress the occurrence of fluctuations in optical loss during intermediate branching and can be easily branched even if the optical fiber cable is not mounted with a release tape. An intermediate branching jig and an optical fiber cable intermediate branching method are provided.

  According to an aspect of the present invention, there is provided a jig for intermediate branching of an optical fiber cable in which a pair of strength members is disposed with an optical fiber interposed therebetween, and the optical fiber and the pair of strength members are collectively covered with a jacket. A body provided with a first groove for fitting the optical fiber cable, and a pair of tensile strengths of the jacket when attached to the bottom of the first groove and the optical fiber cable is fitted into the first groove. A blade that reaches one of a pair of strength members from a surface parallel to a plane connecting the bodies, and moves the blade in a state of being inserted into the sheath, thereby separating the sheath between the pair of strength members A branching jig is provided.

  According to another aspect of the present invention, a pair of strength members are disposed across an optical fiber, the pair of strength members are covered with a pair of coating layers, and the optical fiber and the pair of coating layers are collectively covered with a jacket. An optical fiber cable intermediate branching jig, which is attached to a main body provided with a first groove for fitting the optical fiber cable and a bottom portion of the first groove, and the optical fiber cable is connected to the first optical fiber cable. A blade that reaches one of the pair of coating layers from a surface parallel to a plane connecting the pair of tensile strength members of the outer cover when fitted in the groove, and moves while the blade is inserted into the outer cover Thus, an intermediate branching jig for separating the jacket between the pair of coating layers is provided.

  In one embodiment and other embodiments of the present invention, a plurality of blades may be arranged to cut through a plurality of portions of the jacket.

  In one embodiment and other embodiments of the present invention, the blade may extend obliquely with respect to the cable minor axis direction.

  In one aspect and another aspect of the present invention, the blade may be fixed in the closure together with the optical fiber cable in a state where the blade is inserted into the jacket.

  In one aspect and another aspect of the present invention, the main body further includes a second groove that is orthogonal to the first groove and that fits the optical fiber cable, and the first groove and the orthogonal part of the second groove. A blade may be disposed on the surface.

  In one embodiment and other embodiments of the present invention, the blade may be made of metal.

  According to still another aspect of the present invention, there is provided an intermediate branching method for an optical fiber cable in which a pair of strength members is arranged with an optical fiber interposed therebetween, and the optical fiber and the pair of strength members are collectively covered with an outer sheath. Insert the fiber cable into the groove of the jig for intermediate branching, and make the blade arranged at the bottom of the groove reach one of the pair of tensile bodies from the surface parallel to the plane connecting the pair of tensile bodies of the jacket The step of inserting, the step of separating the jacket between a pair of strength members by moving the intermediate branching jig in the longitudinal direction of the cable with the blade inserted into the jacket, and the location where the jacket is separated And a step of removing the optical fiber from the optical fiber cable.

  According to still another aspect of the present invention, a pair of strength members are disposed across an optical fiber, the pair of strength members are covered with a pair of coating layers, and the optical fiber and the pair of coating layers are collectively covered with a jacket. An optical fiber cable intermediate branching method, in which the optical fiber cable is fitted into the groove of the intermediate branching jig, and the blade disposed at the bottom of the groove is parallel to the plane connecting the pair of tensile strength members of the jacket. Inserting from the surface to reach one of the pair of coating layers and moving the intermediate branching jig in the longitudinal direction of the cable with the blade inserted into the jacket, An intermediate branching method for an optical fiber cable is provided which includes a step of separating the optical fiber cable and a step of taking out the optical fiber from the portion where the jacket is separated.

  In yet another aspect of the present invention, the step of separating the outer cover between the pair of covering layers may separate one of the two outer coverings between the pair of covering layers from the pair of covering layers.

  In yet another aspect of the invention, the step of removing the optical fiber may include bending the optical fiber and the jacket in a direction away from each other.

  In still another aspect of the present invention, after the step of separating the jacket, a step of gripping the optical fiber cable with an intermediate branching jig may be further included.

  According to the present invention, even if the optical fiber cable is not mounted with a release tape, the occurrence of optical loss fluctuation can be suppressed during the intermediate branching, and the optical fiber cable can be easily branched. An intermediate branching jig and an optical fiber cable intermediate branching method can be provided.

It is sectional drawing which shows an example of the optical fiber cable which concerns on embodiment of this invention. FIG. 2A is a cross-sectional view showing an example of the intermediate branching jig according to the embodiment of the present invention. FIG. 2B is a top view showing a part of the intermediate branching jig according to the embodiment of the present invention. FIG. 2C is a top view showing another part of the intermediate branching jig according to the embodiment of the present invention. It is sectional drawing which shows an example at the time of the middle branch of the optical fiber cable which concerns on embodiment of this invention. FIGS. 4A and 4B are perspective views showing an example of the optical fiber cable according to the embodiment of the present invention at the time of intermediate branching. It is sectional drawing which shows an example at the time of the middle branch of the optical fiber cable which concerns on embodiment of this invention. It is sectional drawing which shows another example of the optical fiber cable which concerns on embodiment of this invention. It is sectional drawing which shows another example of the optical fiber cable which concerns on embodiment of this invention, and the jig | tool for intermediate | middle branching. It is sectional drawing which shows an example of the optical fiber cable which concerns on the 1st modification of embodiment of this invention. It is sectional drawing which shows an example of the optical fiber cable which concerns on the 1st modification of embodiment of this invention, and the jig | tool for intermediate | middle branching. It is sectional drawing which shows an example of the optical fiber cable which concerns on the 2nd modification of embodiment of this invention, and the jig | tool for intermediate | middle branching. It is sectional drawing which shows an example of the optical fiber cable which concerns on the 3rd modification of embodiment of this invention, and the jig | tool for intermediate | middle branching. It is a perspective view which shows an example at the time of the middle branch of the optical fiber cable which concerns on the 3rd modification of embodiment of this invention. It is sectional drawing which shows an example at the time of the middle branch of the optical fiber cable which concerns on the 3rd modification of embodiment of this invention. It is a perspective view which shows an example at the time of the middle branch of the optical fiber cable which concerns on the 3rd modification of embodiment of this invention. It is sectional drawing which shows an example of the optical fiber cable which concerns on the 4th modification of embodiment of this invention, and the jig | tool for intermediate | middle branching. It is sectional drawing which shows another example of the optical fiber cable which concerns on the 4th modification of embodiment of this invention, and the jig | tool for intermediate | middle branching. It is a perspective view which shows an example of the optical fiber cable which concerns on the 5th modification of embodiment of this invention, and the jig | tool for intermediate | middle branching. FIG. 18A is a top view showing an example of an optical fiber cable and an intermediate branching jig according to a sixth modification of the embodiment of the present invention. FIG. 18B is a cross-sectional view taken along the line AA in FIG. FIG.18 (c) is sectional drawing of the BB cut surface of Fig.18 (a). FIG. 19A is a perspective view showing an example of an optical fiber cable and an intermediate branching jig according to a sixth modification of the embodiment of the present invention. FIG.19 (b) is sectional drawing of the AA cut surface of Fig.19 (a). FIG.19 (c) is sectional drawing of the BB cut surface of Fig.19 (a). FIG. 20A is a cross-sectional view showing an example of an optical fiber cable and an intermediate branching jig according to a sixth modification of the embodiment of the present invention. FIG.20 (b) is sectional drawing of the AA cut surface of Fig.20 (a). FIG.20 (c) is sectional drawing of the BB cut surface of Fig.20 (a). It is sectional drawing which shows an example of the optical fiber cable which concerns on the 7th modification of embodiment of this invention, and the jig | tool for intermediate | middle branching. It is sectional drawing which shows an example of the optical fiber cable which concerns on the 8th modification of embodiment of this invention, and the jig | tool for intermediate | middle branching. It is sectional drawing which shows an example of the optical fiber cable which concerns on other embodiment of this invention, and the jig | tool for intermediate | middle branching. It is sectional drawing which shows an example of the optical fiber cable which concerns on other embodiment of this invention, and the jig | tool for intermediate | middle branching.

  Next, an embodiment of the present invention and first to eighth modifications will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between the thickness and the planar dimensions, the ratio of the thickness of each layer, and the like are different from the actual ones. Therefore, specific thicknesses and dimensions should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings. Further, the embodiments described below exemplify apparatuses and methods for embodying the technical idea of the present invention, and the technical idea of the present invention includes the material, shape, structure, The layout is not specified as follows. The technical idea of the present invention can be variously modified within the scope of the claims.

(First embodiment)
<Optical fiber cable>
First, an example of an optical fiber cable to which the intermediate branching jig according to the embodiment of the present invention can be applied will be described.

  As shown in FIG. 1, an optical fiber cable 1 according to an embodiment of the present invention includes at least one optical fiber 10 and a pair of strength members 11a arranged in parallel to the optical fiber 10 with the optical fiber 10 interposed therebetween. , 11b, a pair of coating layers 12a, 12b that respectively coat the pair of strength members 11a, 11b, and a jacket 13 that collectively coats the periphery of the optical fiber 10 and the pair of coating layers 12a, 12b.

  The optical fiber 10 is between a plane S1 including the top portions 14a and 14b that are the upper surfaces of the pair of coating layers 12a and 12b and a plane S2 including the top portions 15a and 15b that are the lower surfaces of the pair of coating layers 12a and 12b. It is arrange | positioned in the cylindrical space provided in the jacket 13 so that it may be pinched | interposed into. In the cross section perpendicular to the cable longitudinal direction, each of the top portions 14a, 14b, 15a, and 15b forms a line.

  In the embodiment of the present invention, the number and type of optical fibers 10 are not particularly limited. For example, a collection of 24 optical fiber cores having a diameter of 0.25 mm is used. As the optical fiber 10, a core wire such as an optical fiber strand, an optical fiber core wire, or an optical fiber tape core wire can be adopted. Among these, as the optical fiber ribbon, an intermittently fixed ribbon or the like can be used. Moreover, when it has the several optical fiber 10, you may extend | stretch in parallel without twisting in a longitudinal direction, may be twisted in one direction, may be twisted in SZ shape, and may be twisted in one direction And a composite shape in which SZ twists are interchanged in the middle. Further, a plurality of optical fiber units on which a plurality of optical fibers 10 are mounted may be mounted in the jacket 13. These items can be appropriately determined according to transmission characteristics required by the system, the number of necessary optical fibers 10, and the like. Further, presser winding may be performed around the optical fiber 10, or a string may be wound around the optical fiber 10 to form a unit.

  As a material for the covering layers 12a and 12b and the jacket 13, a resin such as polyvinyl chloride (PVC), polyethylene (PE), nylon (registered trademark), ethylene fluoride or polypropylene (PP) can be used. The same material may be used as the covering layers 12a and 12b and the jacket 13, and different materials may be used. The cross-sectional shape of the coating layers 12a and 12b is not limited to a rectangle, and may be a circle, for example.

  The hardness of the coating layers 12a and 12b is preferably higher than the hardness of the jacket 13. For example, PVC can be used as the outer cover 13, and PP can be used as the covering layers 12a and 12b. By making the hardness of the covering layers 12a and 12b higher than the hardness of the jacket 13, when making a cut in the jacket 13, it is confirmed whether the cut has been made at an appropriate position by the reaction force when the blade is inserted. Can do.

  The jacket 13 is a region sandwiched between the planes S1 and S2 and wraps around the pair of coating layers 12a and 12b. For this reason, the thickness 13 of the jacket 13 in the space for housing the optical fiber 10 is thicker than the thickness T1 at the position corresponding to the top portions 14a, 14b of the pair of coating layers 12a, 12b. Further, in the region sandwiched between the planes S1 and S2 and the side surfaces 16a and 16b on the optical fiber side of the pair of coating layers 12a and 12b, the jacket 13 is sandwiched with the space for housing the optical fiber 10 and the optical fiber 10 interposed therebetween. Is divided.

  The jacket 13 is not fused or bonded to the pair of coating layers 12a, 12b from the top portions 14a, 14b, 15a, 15b of the pair of coating layers 12a, 12b to the side surfaces 16a, 16b on the optical fiber side. The coating layers 12a and 12b are fused or bonded to the pair of coating layers 12a and 12b on the side surfaces 17a and 17b outside the top portions 14a, 14b, 15a and 15b. In the embodiment of the present invention, “fusion” means that the coating layers 12a and 12b and the outer jacket 13 are fused by heat at the time of extrusion molding, and “adhesion” means at the time of extrusion molding. It means that it is bonded by a method different from the fusion by heat.

  The strength members 11a and 11b are made of a metal wire such as a steel wire or fiber reinforced plastic (FRP). The shape of the strength members 11a and 11b is not limited to a linear body, and may be a belt-like body. The band-like body is a long band-like one having a flat cross section, an elliptical shape, or a rectangular shape such as a rectangle.

<Jig for intermediate branch>
Next, an example of the intermediate branching jig of the optical fiber cable 1 according to the embodiment of the present invention will be described.

  The intermediate branching jig 2 according to the embodiment of the present invention has a main body provided with grooves 23 and 24 for fitting the optical fiber cable 1 as shown in FIGS. 2 (a) to 2 (c). 21 and 22 and blades 25a, 25b, 26a and 26b attached to the bottoms of the grooves 23 and 24 of the main bodies 21 and 22.

  The grooves 23 and 24 have a width W4 corresponding to the width W0 of the cable major axis shown in FIG. The width W4 of the grooves 23 and 24 may be equal to the width W0 of the cable major diameter, and when the optical fiber cable 1 is fitted into the grooves 23 and 24, the blades 25a, 25b, 26a, and 26b are covered with a pair of coverings. If it is inserted so as to reach the layers 12a and 12b, it may be wider than the width W0 of the cable major axis.

  Further, the grooves 23 and 24 have depths D1 and D2 corresponding to the height H0 of the minor axis of the cable when integrated with each other. The depths D1 and D2 of the grooves 23 and 24 may coincide with the height H0 of the minor axis of the cable, and when the optical fiber cable 1 is fitted into the grooves 23 and 24, the blades 25a, 25b, 26a, As long as 26b is inserted so as to reach the pair of coating layers 12a and 12b, it may be deeper or shallower than the height H0 of the cable minor axis.

  The length L1 of the blades 25a, 25b, 26a, 26b is equal to or greater than the thickness T1 from the surface of the jacket 13 on the strength members 11a, 11b to the top portions 14a, 14b, 15a, 15b of the coating layers 12a, 12b. Further, the length L1 of the blades 25a, 25b, 26a, and 26b may be adjusted to be less than the thickness T2 reaching the optical fiber 10 from the surface of the jacket 13 on the optical fiber 10. In FIG. 2A, the blades 25a, 25b, 26a, and 26b penetrate the main bodies 21 and 22. However, the present invention is not limited to this.

  Further, the positions of the blades 25a, 25b, 26a, and 26b are the ranges of the top portions 14a, 14b, 15a, and 15b of the coating layers 12a and 12b when the optical fiber cable 1 shown in FIG. It is set to be within W1 and W2.

  As materials for the blades 25a, 25b, 26a, and 26b, metals or alloys such as stainless steel, and plastics can be used. The hardness of the blades 25a, 25b, 26a, 26b may be lower than the hardness of the coating layers 12a, 12b. Thereby, when the blades 25a, 25b, 26a and 26b come into contact with the coating layers 12a and 12b, the coating layers 12a and 12b can be prevented from being damaged.

<Intermediate branching method for optical fiber cable>
Next, an example of an intermediate branching method of the optical fiber cable 1 using the intermediate branching jig 2 according to the embodiment of the present invention will be described.

  (A) As shown in FIG. 3, the optical fiber cable 1 is fitted into the grooves 23 and 24 of the intermediate branching jig 2. At the same time, the blades 25 a, 25 b, 26 a, and 26 b are inserted from two surfaces (also referred to as “cable major diameter surfaces”) facing each other parallel to a plane connecting the pair of strength members 11 a and 11 b of the jacket 13. Reaches the tops 14a, 14b, 15a, 15b of the coating layers 12a, 12b.

  (B) As shown in FIG. 4A, after the main bodies 21 and 22 are fixed so as not to be separated from each other, the intermediate branch treatment is performed with the blades 25a, 25b, 26a, and 26b being inserted into the outer jacket 13. The tool 2 is moved in the cable longitudinal direction (arrow direction), and a cut is made in the jacket 13 as shown in FIG. Note that the blades 25a, 25b, 26a, and 26b need only be deeper than the thickness T1 of the planes S1 and S2 without fixing the main bodies 21 and 22 so as not to be separated from each other.

  (C) As a result, incisions are made at four locations on the jacket 13 located at the top portions 14a, 14b, 15a, 15b of the coating layers 12a, 12b. As a result, it is divided as shown in FIG. At this time, since the pair of coating layers 12a, 12b and the jacket 13 are fused or bonded on the side surfaces 17a, 17b outside the top portions 14a, 14b, 15a, 15b of the pair of coating layers 12a, 12b, The outer cover 13 is divided into four parts, two integrated with each of the pair of coating layers 12a and 12b and two separated from both of the pair of coating layers 12a and 12b.

  (D) Thereafter, the optical fiber 10 is taken out from the portion where the outer jacket 13 is separated. At this time, the outer sheath 13 can be cut as necessary to take out the optical fiber 10.

  According to the intermediate branching jig 2 according to the embodiment of the present invention, when the optical fiber cable 1 is fitted in the grooves 23, 24, the blades 25a, 25b, 26a, 26b are placed on the outer sides of the pair of coating layers 12a, 12b. Guided to be inserted into the jacket 13. For this reason, the blades 25 a, 25 b, 26 a, and 26 b unexpectedly come into contact with the optical fiber 10, or the outer sheath 13 that is displaced by being pushed by the blades 25 a, 25 b, 26 a, and 26 b comes into contact with the optical fiber 10. It is possible to prevent the occurrence of fluctuations in light loss.

  Moreover, since it is not necessary to mount a peeling tape on the optical fiber cable 1, there is no need to cut and remove the peeling tape at the time of intermediate branching, and workability can be improved.

  Further, since the blades 25a, 25b, 26a, 26b may be stabbed into the outer cover 13 in the ranges W1, W2 on the pair of coating layers 12a, 12b, the positions of the blades 25a, 25b, 26a, 26b, the grooves 23, 24. Therefore, it is not necessary to have a very fine dimensional accuracy for the width W4 of the optical fiber, the width W0 of the optical fiber cable 1, and the like.

  When the optical fiber cable 1 is fitted into the grooves 23 and 24 of the intermediate branching jig 2, the blades 25a, 25b, 26a, and 26b are guided to be inserted into the pair of coating layers 12a and 12b. Therefore, even if the jacket 13 of the optical fiber cable 1 does not have a notch for guiding the blades 25a, 25b, 26a, 26b, the jacket 13 on the pair of coating layers 12a, 12b can be cut reliably. it can. When the outer sheath 13 of the optical fiber cable 1 has notches for guiding the blades 25a, 25b, 26a, and 26b, the outer sheath 13 is cut along the blades 25a, 25b, 26a, and 26b along the notches. can do.

  Further, since the optical fiber 10 can be taken out simply by cutting the outer covering 13 on the strength members 11a and 11b with the intermediate branching jig 2, the optical fiber 10 can be branched without being subjected to local bending or the like.

  Further, when the blades 25a, 25b, 26a, and 26b are inserted, a part of the pair of coating layers 12a and 12b may be damaged, but the pair of strength members 11a and 11b are not damaged. There is no impact on yield strength due to tension or compression.

  For example, as shown in FIG. 6, in the optical fiber cable 1 to which the intermediate branching jig 2 is applied, the thickness of the jacket 13 on the covering layers 12a and 12b is the outer space on the space where the optical fiber 10 is accommodated. It may be approximately the same as the thickness of the cover 13. As shown in FIG. 7, when the optical fiber cable 1 is fitted into the grooves 23, 24 of the intermediate branching jig 2, the blades 25a, 25b, 26a, 26b are arranged so as to reach the coating layers 12a, 12b. ing. For this reason, it is possible to prevent the blades 25a, 25b, 26a, and 26b from being pierced into the jacket 13 in the space in which the optical fiber 10 is accommodated, and the occurrence of fluctuations in light loss can be suppressed.

(First modification)
As a first modification of the embodiment of the present invention, as shown in FIG. 8, the pair of tensile strength members 11 a and 11 b are directly covered with the jacket 13 without having the pair of covering layers 12 a and 12 b. The case where the intermediate branching jig 2 is applied to the structured optical fiber cable 1 will be described.

  In the optical fiber cable 1 shown in FIG. 8, the jacket 13 is divided on the side surface of the pair of strength members 11 a and 11 b on the optical fiber side with the space for housing the optical fiber 10 and the optical fiber 10 interposed therebetween. In FIG. 8, the maximum thickness of the jacket 13 on the pair of strength members 11a and 11b is thicker than the maximum thickness of the jacket 13 in the space in which the optical fiber 10 is accommodated, but this is the reverse relationship. May be.

  As shown in FIG. 9, the intermediate branching jig 2 includes main bodies 21 and 22 provided with grooves 23 and 24 for fitting the optical fiber cable 1, and blades 25a attached to the bottoms of the grooves 23 and 24. 25b, 26a, 26b.

  The grooves 23 and 24 of the main bodies 21 and 22 are set to the same width as the width W0 of the cable major axis shown in FIG. 8, and are set to the same depth as the cable minor axis when integrated with each other.

  The lengths of the blades 25a, 25b, 26a, and 26b are parallel to a plane that connects the blades 25a, 25b, 26a, and 26b to the pair of strength members 11a and 11b when the optical fiber cable 1 is fitted in the grooves 23 and 24. From the surface of the outer casing 13, the tension members 11a and 11b are set. The positions of the blades 25a, 25b, 26a, and 26b are set so as to be within the ranges W5 and W6 on the strength members 11a and 11b when the optical fiber cable 1 is fitted into the grooves 23 and 24.

  According to the first modification of the embodiment of the present invention, when the optical fiber cable 1 is fitted into the grooves 23 and 24 of the intermediate branching jig 2 as shown in FIG. 9, the blades 25a, 25b, 26a and 26b are inserted. Is inserted into the jacket 13 on the pair of strength members 11a and 11b and guided so as to reach the strength members 11a and 11b. Therefore, the blades 25a, 25b, 26a, and 26b do not contact the optical fiber 10, and the outer sheath 13 that is displaced by being pushed by the blades 25a, 25b, 26a, and 26b does not contact the optical fiber 10, Occurrence of fluctuations in optical loss can be suppressed.

(Second modification)
As shown in FIG. 10, the intermediate branching jig 2 according to the second modification of the embodiment of the present invention includes a main body 21 provided with a groove 23 for fitting the optical fiber cable 1, and a main body 21. The point provided with the cover part 29 to cover differs from the structure which has the two main bodies 21 and 22 shown in FIG.

  Blades 25 a and 25 b are attached to the bottom of the groove 23 of the main body 21. Further, blades 26 a and 26 b are attached to the inside of the lid portion 29. The groove 23 has the same width as the major axis of the optical fiber cable 1 and the same depth as the minor axis of the cable.

  When the intermediate branching jig 2 is moved in the longitudinal direction of the cable after the lid 29 is fixed so that it cannot be removed, the jacket 13 on the tensile strength members 11a and 11b at the moved positions is cut. Even if the lid 29 is not fixed so as not to be removed, it is sufficient if the intermediate branching jig 2 can be moved in a state where the blades 25a, 25b, 26a, 26b reach the tensile strength members 11a, 11b. As a result, the two outer sheaths 13 in which the strength members 11a and 11b are integrated, the two outer sheaths 13 in which none of the strength members 11a and 11b are integrated, and the optical fiber 10 (optical fiber unit). And divided.

  According to the intermediate branching jig 2 shown in FIG. 10, when the optical fiber cable 1 is fitted in the groove 23, the blades 25a, 25b, 26a, and 26b are securely inserted into the jacket 13 on the strength members 11a and 11b. can do. Therefore, the blades 25a, 25b, 26a, and 26b are prevented from coming into contact with the optical fiber 10, and the jacket 13 that is displaced by being pushed by the blades 25a, 25b, 26a, and 26b is prevented from coming into contact with the optical fiber 10. And the occurrence of fluctuations in optical loss can be suppressed.

  In addition, when the mechanism which positions so that the blades 25a and 25b of the main body 21 and the blades 26a and 26b of the cover part 29 face each other when the cover part 29 is closed, a groove is formed inside the cover part 29. It is not necessary to provide it.

<First embodiment>
Here, an optical fiber cable 1 and an intermediate branching jig 2 as shown in FIG. 10 were produced. The cable dimensions were such that the major axis was 3.6 mm, the minor axis was 2.0 mm, and the distance between the centers of the strength members 11 a and 11 b was 2.6 mm. The covering layers 12a and 12b have a rectangular cross-sectional shape, the dimensions of the covering layers 12a and 12b are a width of 1.0 mm and a thickness of 1.5 mm, and the thickness of the jacket 13 directly above the strength members 11a and 11b is 0. 25 mm.

  On the other hand, the dimensions of the intermediate branching jig 2 are such that the width of the groove 23 is 3.8 mm, the distance between the blades 25a, 25b, 26a, and 26b is 2.6 mm, and the height of the blades 25a, 25b, 26a, and 26b is 0.4 mm. .

  By inserting the optical fiber cable 1 into the groove 23 of the intermediate branching jig 2, the blades 25 a, 25 b, 26 a, 26 b are inserted into the optical fiber cable 1 for a height of 0.4 mm. By moving the intermediate branching jig 2 in the longitudinal direction of the cable, a jacket 13 (full length of 0.25 mm thickness) on the strength members 11a and 11b and part of the coating layers 12a and 12b of the strength members 11a and 11b (From the contact surface with the jacket 13 to a depth of 0.15 mm) is cut.

  When the transmission loss fluctuation from when the optical fiber cable 1 was fitted into the groove 23 until the optical fiber core wire was taken out was measured, the loss fluctuation was as good as 0.1 dB or less. Further, since the optical fiber core wire can be taken out only by cutting the jacket 13 on the coating layers 12a and 12b with the intermediate branching jig 2, the optical fiber core wire can be branched without being locally bent. did it.

<Second embodiment>
When the optical fiber cable 1 without the V-shaped notch for guiding the blades 25a, 25b, 26a, and 26b is intermediately branched, it is not necessary to sharply sharpen the tips of the blades 25a, 25b, 26a, and 26b. On the other hand, when the blades 25a, 25b, 26a, and 26b are inserted into the V-shaped notches, the blades 25a, 25b, 26a, and the blades 25a, 25b, 26a, 26b cannot be applied, and the jacket 13 may not be divided.

  Therefore, the intermediate branching jig 2 was produced using blades 25a, 25b, 26a, and 26b of different materials. As the blades 25a, 25b, 26a, and 26b, a plastic (polycarbonate, thickness 0.3 mm) plate and a metal plate (SUS403, thickness 0.3 mm) were used. The tips of the blades 25a, 25b, 26a, 26b are not sharpened in the thickness direction.

  Using the produced intermediate branching jig 2, the optical fiber cable 1 without a notch as shown in FIG. 1 was branched. Even when the intermediate branching jig 2 using a plastic plate for the blades 25a, 25b, 26a and 26b and the intermediate branching jig 2 using a metal plate are used, the optical fiber cable 1 is branched. It was possible. Although polyethylene is used for the jacket 13, when the blades 25a, 25b, 26a, and 26b are made of a material harder than polyethylene, it can be branched.

  When the blades 25a, 25b, 26a, and 26b are made of a material softer than the outer cover 13 or a material having an equivalent hardness, it is difficult to branch. For example, when an acrylic plate or the like is used for the blades 25a, 25b, 26a, and 26b, the polyethylene can be scratched, but it is difficult to cut the jacket 13.

(Third Modification)
As shown in FIG. 11, the intermediate branching jig 2 according to the third modification of the embodiment of the present invention includes one main body 21 provided with a groove 23 for fitting the optical fiber cable 1, and a main body 2 includes two blades 25a and 25b arranged at the bottom of the groove 23, and has two main bodies 21 and 22 shown in FIG. 2, and four blades 25a, 25b, 26a, Different from the configuration having 26b.

  At the time of intermediate branching, as shown in FIG. 11, the optical fiber cable 1 is fitted into the groove 23 of the main body 21, and the optical fiber cable 1 is pressed by hand so that the optical fiber cable 1 does not jump out of the groove 23. The branching jig 2 is moved in the cable longitudinal direction. As a result, as shown in FIG. 13, a part of the jacket 13 on one side of the cable long diameter surface is separated by the blades 25a and 25b. Furthermore, as shown in FIG. 14, the optical fiber 10 and the jacket 13 including the tensile members 11a and 11b are moved away from the plane connecting the pair of tensile members 11a and 11b in the opposite direction, so that the optical fiber 10 The fiber 10 can be removed. Furthermore, the deflection F and the extra length of the optical fiber 10 can be ensured.

  Note that the intermediate branching jig 2 shown in FIG. 11 may further include a lid portion that does not have a blade in order to cover the groove 23 of the main body 21.

(Fourth modification)
As shown in FIG. 15, the intermediate branching jig 2 according to the fourth modification of the embodiment of the present invention includes main bodies 21 and 22 provided with grooves 23 and 24, and grooves 23 of the main bodies 21 and 22. , 24 is different from the configuration having four blades 25a, 25b, 26a, 26b shown in FIG.

  The blade 25a is disposed so as to reach the outer cover 13 on the covering layer 12a. On the other hand, the blade 26b is disposed so as to reach the outer jacket 13 below the coating layer 12b. According to the intermediate branching jig 2 shown in FIG. 15, after the optical fiber cable 1 is fitted into the intermediate branching jig 2, the intermediate branching jig 2 is moved in the longitudinal direction of the cable, whereby the jacket 13 Can be divided into two.

  Further, as shown in FIG. 16, the intermediate branching jig 2 includes the main bodies 21 and 22 provided with the grooves 23 and 24, and the blade provided facing the bottoms of the grooves 23 and 24 of the main bodies 21 and 22. 25a and 26a may be provided. The blade 25a is disposed so as to reach the outer cover 13 on the covering layer 12a. On the other hand, the blade 26a is disposed so as to reach the outer jacket 13 below the coating layer 12a. According to the intermediate branching jig 2 shown in FIG. 16, after the optical fiber cable 1 is fitted into the intermediate branching jig 2, the intermediate branching jig 2 is moved in the longitudinal direction of the cable, so that the jacket 13 Can be divided into two.

(Fifth modification)
As a fifth modification of the embodiment of the present invention, an example in which the intermediate branching jig 2 is used as a gripping member for the optical fiber cable 1 will be described.

  After the intermediate branching of the optical fiber cable 1, the intermediate branching portion of the optical fiber cable 1 may be fixed in the closure. As shown in FIG. 17, after the intermediate branching of the optical fiber cable 1, the intermediate branching jig 2 is sandwiched between the fixing members 31 and 32, and the optical fiber cable 1 is inserted and fixed. At this time, the blades 25a, 25b, 26a, and 26b of the intermediate branching jig 2 are inserted into the outer jacket 13, and the outer jacket 13 can be gripped. In this state, the optical fiber cable 1 together with the intermediate branching jig 2 is fixed in the closure. Since the blades 25 a, 25 b, 26 a, and 26 b are pierced into the jacket 13 on the coating layers 12 a and 12 b of the optical fiber cable 1, the optical fiber cable 1 can be gripped without contacting the optical fiber 10. As a result, it is possible to prevent loss fluctuation at the time of fixing.

(Sixth Modification)
As shown in FIGS. 18A to 18C, the intermediate branching jig 2 according to the sixth modification of the embodiment of the present invention is a second one orthogonal to the first grooves 23 and 24. 2 is different from the structure having only the first grooves 23 and 24 shown in FIG.

  The second grooves 27 and 28 have the same width and depth as the first grooves 23 and 24. Blades 25a, 25b, 26a, and 26b are arranged at portions where the first grooves 23 and 24 and the second grooves 27 and 28 are orthogonal to each other. The directions of the blades 25a, 25b, 26a, and 26b are parallel to the first grooves 23 and 24.

  As shown in FIGS. 19A to 19C, when the optical fiber cable 1 is branched, the optical fiber cable 1 is fitted into the first grooves 23 and 24 of the intermediate branching jig 2. The blades 25a, 25b, 26a, and 26b are inserted into the jacket 13. Thereafter, the jacket 13 is cut by moving the intermediate branching jig 2 in the cable longitudinal direction.

  After the intermediate branching of the optical fiber cable 1, the intermediate branching jig 2 is removed, and the optical fiber cable 1 is inserted into the second grooves 27 and 28 as shown in FIGS. 20 (a) to 20 (c). At this time, the blades 25 a, 25 b, 26 a and 26 b of the intermediate branching jig 2 are inserted into the jacket 13. In this state, the optical fiber cable 1 is fixed to the closure together with the intermediate branching jig 2.

  According to the sixth modification of the embodiment of the present invention, since the blades 25a, 25b, 26a, and 26b can fix and grip the optical fiber cable 1 without contacting the optical fiber 10, Loss fluctuations can be prevented.

  Also, when the blades 25a, 25b, 26a, and 26b for dividing the outer cover 13 are used as they are, the gripping is performed when the outer cover 13 can be easily cut or when the blades 25a, 25b, 26a, and 26b are sharp. The outer sheath 13 may be cut when a tensile force or the like is applied to the optical fiber cable 1. On the other hand, according to the sixth modification of the embodiment of the present invention, when the second grooves 27 and 28 are provided and the intermediate branching jig 2 is rotated by 90 ° after the intermediate branching and gripped, The direction of the blades 25a, 25b, 26a, and 26b inserted into the jacket 13 changes. For this reason, even if force, such as a tension | tensile_strength, is applied to the optical fiber cable 1, it can prevent that the jacket 13 is cut | disconnected.

  Further, when the intermediate branching jig 2 is rotated by 90 °, the place where the blades 25 a, 25 b, 26 a, 26 b are inserted changes, and the blades 25 a, 25 b, 26 a, 26 b are inserted immediately above the optical fiber 10. And cause fluctuations in loss. Therefore, according to the sixth modification of the embodiment of the present invention, the positions of the blades 25a, 25b, 26a, and 26b are placed on the strength members 11a and 11b even if the intermediate branching jig 2 is rotated by 90 °. It is possible to prevent loss fluctuations by shifting the positions so as to be twisted.

(Seventh Modification)
As shown in FIG. 21, the intermediate branching jig 2 according to the seventh modification of the embodiment of the present invention is disposed at the main body 21 provided with the groove 23 and at the bottom of the groove 23 of the main body 21. 2 is different from the structure shown in FIG. 2 in that it includes blades 25a and 25b, a lid portion 29 fitted to the main body 21 so as to cover the groove 23, and blades 26a and 26b arranged inside the lid portion 29.

  The direction of the blades 26a and 26b is directed in the direction orthogonal to the direction of the blades 25a and 25b. According to the intermediate branching jig 2 shown in FIG. 21, the optical fiber cable 1 can be fixed to the intermediate branching jig 2 and can be gripped. The lid 29 may be provided with demons (protrusions) that can be inserted into the jacket 13 instead of the blades 26a and 26b.

(Eighth modification)
In the intermediate branching jig 2 according to the eighth modification of the embodiment of the present invention, as shown in FIG. 22, the blades 25a, 25b, 26a, and 26b extend obliquely with respect to the cable minor axis direction. This is different from the structure in which the blades 25a, 25b, 26a, and 26b shown in FIG. 2 extend in parallel to the cable minor axis direction.

  The angles and hardness of the blades 25a, 25b, 26a, and 26b are determined so that the blades 25a, 25b, 26a, and 26b are inserted into the jacket 13 when the optical fiber cable 1 is fitted into the intermediate branching jig 2, and the coating layers 12a, What is necessary is just to adjust suitably so that it may reach 12b.

  According to the intermediate branching jig 2 shown in FIG. 22, the cut outer sheath 13 is easily lifted during intermediate branching, and the removal of the outer sheath 13 and the removal of the optical fiber 10 are facilitated.

(Other embodiments)
As described above, the present invention has been described with the embodiment and the first to eighth modifications. However, it should not be understood that the description and drawings constituting a part of this disclosure limit the present invention. . From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  For example, FIG. 1 illustrates the case where the cross-sectional shapes of the covering layers 12a and 12b are rectangular, but the cross-sectional shapes of the covering layers 12a and 12b are not particularly limited. For example, as shown in FIG. 23, the cross-sectional shapes of the coating layers 12a and 12b may be circular. In this case, the blades 25a, 25b, 26a and 26b of the intermediate branching jig 2 are adjusted so as to reach the coating layers 12a and 12b when the optical fiber cable 1 is fitted into the intermediate branching jig 2.

  Further, as shown in FIG. 24, in the optical fiber cable 1 having a self-supporting structure, the neck 3 may remain on the short diameter side of the optical fiber cable 1 after the support wire 4 is removed (in FIG. 24, the support 3 is supported). Line 4 is also shown). Therefore, the main bodies 21 and 22 of the intermediate branching jig 2 may be configured to have a gap corresponding to the thickness of the neck portion 3 when facing each other.

  As described above, the present invention naturally includes various embodiments not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

DESCRIPTION OF SYMBOLS 1 ... Optical fiber cable 2 ... Intermediate | middle branch jig | tool 3 ... Neck part 4 ... Support line 10 ... Optical fiber 11a, 11b ... Strength body 12a, 12b ... Covering layer 13 ... Outer sheath 14a, 14b, 15a, 15b ... Top part 16a, 16b ... Side 17a, 17b ... Side 21, 22 ... Main body 23, 24, 27, 28 ... Groove 29 ... Ladder 25a, 25b, 26a, 26b ... Blade 31, 32 ... Fixing member

Claims (11)

An intermediate branching jig of an optical fiber cable in which a pair of strength members is disposed across an optical fiber, and the optical fiber and the pair of strength members are collectively covered with a jacket,
A main body provided with a first groove for fitting the optical fiber cable;
The pair of strength members attached to the bottom of the first groove from the surface parallel to a plane connecting the pair of strength members of the jacket when the optical fiber cable is fitted into the first groove. A blade that reaches one of the following:
By moving the blade in a state of being inserted into the jacket, the jacket between the pair of strength members is separated ,
An intermediate branching jig which is fixed in a closure together with the optical fiber cable in a state where the blade is inserted into the jacket . An intermediate branching jig of an optical fiber cable in which a pair of strength members is disposed across an optical fiber, and the optical fiber and the pair of strength members are collectively covered with a jacket,
A main body provided with a first groove for fitting the optical fiber cable;
The pair of strength members attached to the bottom of the first groove from the surface parallel to a plane connecting the pair of strength members of the jacket when the optical fiber cable is fitted into the first groove. A blade that reaches one of the following:
By moving the blade in a state of being inserted into the jacket, the jacket between the pair of strength members is separated ,
The body further comprises a second groove perpendicular to the first groove for fitting the optical fiber cable;
The intermediate branching jig , wherein the blade is disposed in a portion where the first groove and the second groove are orthogonal to each other . A pair of strength members are disposed across an optical fiber, the pair of strength members are covered with a pair of coating layers, and the optical fiber and the pair of coating layers are intermediately covered with a jacket. A branching jig,
A main body provided with a first groove for fitting the optical fiber cable;
When the optical fiber cable is fitted into the first groove, the pair of coating layers from the surface parallel to the plane connecting the pair of tensile strength members of the jacket when attached to the bottom of the first groove A blade that reaches one of the following:
By moving the blade in a state of being inserted into the jacket, the jacket between the pair of coating layers is separated ,
An intermediate branching jig which is fixed in a closure together with the optical fiber cable in a state where the blade is inserted into the jacket . A pair of strength members are disposed across an optical fiber, the pair of strength members are covered with a pair of coating layers, and the optical fiber and the pair of coating layers are intermediately covered with a jacket. A branching jig,
A main body provided with a first groove for fitting the optical fiber cable;
When the optical fiber cable is fitted into the first groove, the pair of coating layers from the surface parallel to the plane connecting the pair of tensile strength members of the jacket when attached to the bottom of the first groove A blade that reaches one of the following:
By moving the blade in a state of being inserted into the jacket, the jacket between the pair of coating layers is separated ,
The body further comprises a second groove perpendicular to the first groove for fitting the optical fiber cable;
The intermediate branching jig , wherein the blade is disposed in a portion where the first groove and the second groove are orthogonal to each other . The intermediate branching jig according to any one of claims 1 to 4 , wherein a plurality of the blades are arranged to cut through a plurality of portions of the outer jacket. Said blade, an intermediate branch jig according to any one of claims 1 to 5, characterized in that extending obliquely with respect to the cable minor axis. The jig for intermediate branching according to any one of claims 1 to 6 , wherein the blade is made of metal. A pair of strength members is disposed across an optical fiber, and an optical fiber cable intermediate branching method in which the optical fiber and the pair of strength members are collectively covered with a jacket,
The optical fiber cable is fitted into the groove of the intermediate branching jig, and the blade disposed at the bottom of the groove is moved from the surface parallel to the plane connecting the pair of strength members of the outer jacket to the pair of strength members. Inserting to reach one, and
Separating the jacket between the pair of strength members by moving the intermediate branching jig in the cable longitudinal direction with the blade inserted in the jacket;
Look including the step of taking out the optical fiber from where the separation of the envelope,
An intermediate branching method for an optical fiber cable, further comprising the step of gripping the optical fiber cable with the intermediate branching jig after the step of separating the jacket . A pair of strength members are disposed to sandwich the optical fiber, the pair of strength members are coated with a coating layer of a pair, the intermediate branch of the optical fiber cable collectively covering the optical fiber and the pair of coating layer jacket A method,
The optical fiber cable is fitted into the groove of the intermediate branching jig, and the blade disposed at the bottom of the groove is moved from the surface parallel to the plane connecting the pair of strength members of the jacket to the pair of coating layers. Inserting to reach one, and
Separating the jacket between the pair of coating layers by moving the intermediate branching jig in the cable longitudinal direction with the blade inserted into the jacket;
Look including the step of taking out the optical fiber from where the separation of the envelope,
An intermediate branching method for an optical fiber cable, further comprising the step of gripping the optical fiber cable with the intermediate branching jig after the step of separating the jacket . 10. The light according to claim 9 , wherein the step of separating the jacket between the pair of coating layers separates one of the two jackets between the pair of coating layers from the pair of coating layers. Intermediate branching method for fiber cable.   11. The optical fiber cable intermediate branching method according to claim 8, wherein the step of taking out the optical fiber includes bending the optical fiber and the jacket in a direction away from each other. .

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