JP2007127886A - Optical fiber cable - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve processibility of stripping and mid-span branching of a cable by enabling a sheath to be torn and removed easily without damaging the cable core of an optical fiber cable. <P>SOLUTION: In the optical fiber cable 1 having a cable core 3 in which an optical fiber is housed, and a cable sheath 5 covering the outer periphery of the cable core 3, at least one rip cord 7 is buried in the cable sheath 5 in such a manner that it extends in the longitudinal direction of the cable sheath 5. A loop-shaped extra length part 7B is formed in the rip cord 7 at intervals in the longitudinal direction of the rip cord 7 and in the thickness direction of the cable sheath 5, and is buried inside the cable sheath 5. A part of each loop-shaped extra length part 7B is configured in such a manner that it is exposed on the outer surface of the cable sheath 5, or it projects in the neighborhood of the outer surface of the cable sheath 5. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an optical fiber cable, and more particularly to an improvement in workability of cable lead-out and intermediate post-branching, and to an optical fiber cable that can easily peel and remove a cable sheath without damaging the cable core.

  As shown in FIG. 7, the conventional optical fiber cable 101 with excellent branching property is an optical fiber such as an optical fiber, an optical fiber, an optical fiber tape, or a loose tube. A cable core 103 in which an optical fiber of the form is accommodated, and a cable sheath 105 (outer jacket) such as a resin coated on the outer periphery of the cable core 103 is known. In FIG. 7 showing the transverse cross section of the optical fiber cable 101, a lip cord 107 (a tear string) provided on the left and right sides and in contact with the outer surface of the cable core 103, and the lip A structure in which a tension member 109 disposed inside the cable sheath 105 with a displacement of about 90 ° in the circumferential direction of the cable sheath 105 with respect to the cord 107 is mounted is common.

  In addition, as a self-supporting type (SS type) optical fiber cable 111 of another example, as shown in FIG. 8, a tensile strength body 113 (for example, a steel stranded wire obtained by twisting seven steel wires) Is provided with a long cable support line part 117 whose sheath is covered with a sheath resin 115, and the cable support line part 117 is integrated in parallel with the optical fiber cable 101 via a neck part 119. Yes.

  In the intermediate post-branching operation for extracting the optical fiber in the cable core 103 from the middle of the optical fiber cable 101, it is necessary to peel off the sheath 105 without damaging the optical fiber in the cable core 103. When the sheath 105 is peeled off at the time of branching after the middle, the lip cord 107 mounted in the optical fiber cable 101 in advance is taken out, the lip cord 107 is pulled to tear the cable sheath 105, and the optical fiber in the cable core 103 is removed. A method of taking out the fiber is adopted.

  However, in the structure of the conventional optical fiber cable 101, in order to take out the lip cord 107 in advance, a method of carefully cutting off the sheath 105 with a blade is taken, which is very troublesome and damages the internal optical fiber. There was a danger of giving.

  As a countermeasure, a structure has been proposed in which the lip cord 107 is attached in the vicinity of the tension member 109 embedded in the cable sheath 105 to prevent the blade from reaching the inside of the cable core 103. There are problems that the adhesion between the tension member 109 and the cable sheath 105 is adversely affected, and the tension member 109 is damaged when the lip cord 107 is taken out.

  Therefore, in order to further improve the workability of the above-described lead-out and intermediate post-branching, in recent years, as shown particularly in FIG. 3 of Patent Document 1, the optical fiber cable has been cut in the longitudinal direction of the cable. A plurality of lip cords are embedded in the cable sheath so as to be continuous in the longitudinal direction, and a part of each lip cord is exposed on the outer surface of the cable sheath. By pulling the exposed portion of the lip cord, the cable sheath is torn.

  As another example, as disclosed in Patent Document 2, the optical fiber cable has a lip cord embedded in a radial direction of a cable sheath having a cross section perpendicular to the longitudinal direction of the optical fiber cable. Both ends of the cord are exposed on the outer surface of the cable sheath. The cable sheath is torn in the longitudinal direction of the cable by pulling it in the longitudinal direction of the cable while holding both ends of the lip cord exposed on the outer surface of the cable sheath.

  As another example, as shown in Patent Document 3, the optical fiber cable has a lip cord that is intermittently radially outward from the cable core (the thickness of the cable sheath) over the entire length of the cable. It is embedded in the cable sheath. Furthermore, the mark which displays the side part of said lip cord is provided on the outer surface of the cable sheath. If the cable sheath at the mark portion is scraped off, the side portion of the lip cord is taken out without being cut deeply into the cable core, and the cable sheath is torn in the longitudinal direction of the cable by pulling the side portion.

  As another example, as shown in FIGS. 7 and 8 of Patent Document 4 in particular, the optical fiber cable has a lip cord formed of a sheet-like mesh member over the entire length of the cable. It is buried in the vertical direction. The cable sheath is torn in the longitudinal direction of the cable by pulling the lip cord made of the sheet-like mesh member in the longitudinal direction of the cable.

As another example, as shown in Patent Document 5, an optical fiber cable has a ladder-like lip cord embedded in the longitudinal direction of the cable sheath and a ladder-like lateral portion. Exposed on the outer surface of the cable sheath. The cable sheath is torn by hooking and pulling the exposed ladder-like lateral portion using a tool such as a hook.
Japanese Patent Laid-Open No. 11-185534 Japanese Patent Laid-Open No. 11-185535 JP 2002-55236 A JP 2002-98871 A USP 6798957 Publication

  By the way, in the conventional optical fiber cable described above, in Patent Document 1, when the exposed portion of the lip cord is pulled, a tearing portion can be provided in the cable sheath, but the lip cord is cut in the longitudinal direction. When the length of one lip cord to be pulled is not sufficient, there is a problem that it takes time and effort because another lip cord needs to be pulled and torn.

  In Patent Document 2, since the lip cord is embedded in the radial direction of the cable sheath having a cross section perpendicular to the longitudinal direction of the optical fiber cable, when the cable core is at the center of the optical fiber cable, the optical fiber is damaged. It is necessary to bury the cable core away from the cable core so as not to interfere. In addition, even when the cable core is not located at the center of the optical fiber cable, it is necessary to avoid the cable core, so that there is a problem that the manufacturing complexity and the application range are narrow.

  In addition, to tear the cable sheath, pull both ends of the lip cord exposed on the outer surface of the cable sheath and pull it in the longitudinal direction of the cable. However, it is necessary to tear the cable sheath that is approximately the length of the optical fiber cable. There was a problem that it was not easy. In addition, since the lip cord avoids the cable core, the cable sheath slightly covers the periphery of the cable core even after the cable sheath is torn, and it is necessary to tear this cable sheath. was there.

  Further, in Patent Document 3, since the lip cord is embedded in the cable sheath so as to protrude radially outward (in the thickness direction of the cable sheath) from the cable core intermittently over the entire length of the cable. There are problems that the cable sheath cannot be seen from the outer surface and that the cable sheath needs to be shaved in order to take out the lip cord. Furthermore, in order to make it easy to take out the lip cord, there is a problem that it takes a complicated device and trouble to provide the mark for displaying the side portion of the lip cord on the outer surface of the cable sheath.

  Further, in Patent Document 4, since the lip cord made of a sheet-like mesh member is embedded in the cable sheath thickness direction, the cable sheath is not visible from the outer surface of the cable sheath, and the cable sheath is shallow to take out the lip cord. There was a problem that even if it was cut, it took time. Moreover, since the thickness of the cable sheath at the position of the sheet-like mesh member is reduced, there is a problem that the mechanical strength is weakened.

  Moreover, in patent document 5, since the lip cord was a ladder shape, there was a problem that it was expensive.

  The present invention has been made to solve the above-described problems.

In order to achieve the problem to be solved by the above invention, an optical fiber cable of the present invention is an optical fiber cable having a cable core containing an optical fiber and a cable sheath coated on the outer periphery of the cable core.
At least one lip cord is embedded in the cable sheath so as to extend in the longitudinal direction of the cable sheath, and the lip cord is intermittently looped in the longitudinal direction of the lip cord in the thickness direction of the cable sheath. An extra length portion is formed and embedded in the cable sheath, and a part of each loop-like extra length portion is exposed on the outer surface of the cable sheath or protrudes in the vicinity of the outer surface of the cable sheath. It is characterized by being arranged in this way.

The optical fiber cable of the present invention is an optical fiber cable having a cable core containing an optical fiber and a cable sheath coated on the outer periphery of the cable core.
First lip cords extending in the longitudinal direction of the cable sheath are alternately arranged on a first inner surface portion located on the inner surface side of the cable sheath and a first outer surface portion located on the outer surface side of the cable sheath. And the 2nd inner surface part and the 1st lip cord which the 2nd lip cord extended in the longitudinal direction of the cable sheath is located in the inner surface side of the cable sheath corresponding to the 1st outer surface part of the 1st lip cord The second outer surface portion located on the outer surface side of the cable sheath corresponding to the first inner surface portion of the cable sheath is alternately arranged and embedded in the cable sheath,
The first outer surface portion of the first lip cord and the second outer surface portion of the second lip cord are arranged so as to be exposed on the outer surface of the cable sheath or protrude in the vicinity of the outer surface of the cable sheath. It is characterized by being.

  As can be understood from the means for solving the above problems, according to the optical fiber cable of the present invention, a part of the loop-like surplus portion of the lip cord is exposed on the outer surface of the cable sheath, or the cable sheath Since it is arranged and configured so as to protrude in the vicinity of the outer surface, the loop-like extra length can be easily found and pulled. Therefore, it is possible to easily tear the cable sheath by pulling the lip cord without scraping off the cable sheath, and there is no trouble, and the possibility of damaging the optical fiber inside the cable core can be greatly reduced. Moreover, since the loop-like surplus portion is provided intermittently in the longitudinal direction of the cable sheath, there is almost no adverse effect on the mechanical strength of the cable sheath.

  According to the optical fiber cable of the present invention, the first outer surface portion of the first lip cord and the second outer surface portion of the second lip cord are exposed on the outer surface of the cable sheath or in the vicinity of the outer surface of the cable sheath. Since the first outer surface portion of the first lip cord and the second outer surface portion of the second lip cord are found, the first outer surface portion and the second lip of the first lip cord are found. Either one or both of the second outer surface portions of the cord can be easily pulled. Therefore, it is possible to easily tear the cable sheath by pulling the lip cord without scraping off the cable sheath, so that there is no trouble and the possibility of damaging the optical fiber inside the cable core can be greatly reduced. In addition, since the first outer surface portion of the first lip cord and the second outer surface portion of the second lip cord are provided intermittently in the longitudinal direction of the cable sheath, the mechanical strength of the cable sheath is almost adversely affected. Absent.

  Embodiments of the present invention will be described below with reference to the drawings.

  Referring to FIGS. 1A and 1B, an optical fiber cable 1 according to a first embodiment is an optical fiber such as an optical fiber, an optical fiber, an optical fiber tape, or a loose fiber. A cable core 3 in which an optical fiber of another form such as a tube is accommodated, and a cable sheath 5 (outer sheath) such as a resin coated on the outer periphery of the cable core 3 are provided. In addition, as said cable core 3, the one-way slot and SZ slot which accommodated said optical fiber in the slot groove | channel can also be used as the cable core 3. FIG.

  Further, in the cable sheath 5 described above, a pair of lip cords 7 (tearing) extending substantially parallel to the longitudinal direction of the cable core 3 at opposite positions on the left and right sides with the cable core 3 in FIG. String) is buried.

  More specifically, the lip cord 7 includes a sheath tearing portion 7A attached to the outer surface of the cable core 3 in the longitudinal direction, and intermittently with respect to the sheath tearing portion 7A in the longitudinal direction of the cable core 3. 1B having a loop-like surplus portion 7B formed in a loop shape, the loop-like surplus portion 7B being directed in the thickness direction (radial direction) of the cable sheath 5 and in FIG. The upper portion of the loop-like extra length portion 7B is disposed so as to protrude from the cable core 3 toward the outer surface of the cable sheath 5.

  In this embodiment, the loop-like extra length 7B is formed, for example, in an “E” shape in the thickness direction of the cable sheath 5 in FIG. 1B, the sheath tearing portion 7A is attached to the outer surface of the cable core 3 and is bent at a predetermined position so that the thickness direction of the cable sheath 5 (cable It rises to the outside of the outer diameter of the sheath 5 and is bent to the left in the outer surface near the outer surface of the cable sheath 5. It extends to the left by a short distance and then bent 180 ° upward and extends to the right at a position where it is raised near the outer surface of the cable sheath 5. After extending to the right by about twice the distance extending leftward, it is bent 180 ° downward and leftward. Next, it is bent downward (inside of the diameter of the cable sheath 5) along the rising portion. The outer surface of the cable core 3 extends rightward along the outer surface of the cable core 3.

  As shown in FIG. 1B, the above “E-shaped” loop-shaped surplus portion 7 </ b> B is intermittently formed at appropriate intervals in the longitudinal direction of the lip cord 7.

  In the first embodiment, the lip cord 7 is arranged in a pair on both sides of the cable core 3 on the line passing through the substantially center of the cable core 3. It is sufficient that the lip cords 7 are arranged, and three or more lip cords 7 may be arranged, and the invention is not limited.

  Next, an intermediate post-branching method of the optical fiber cable 1 will be described. As shown in FIGS. 1 (A) and 1 (B), a loop-like surplus portion 7B of the lip cord 7 is provided in the cable sheath 5 at a so-called intermediate rear branch portion that branches in the middle of the optical fiber cable 1. Since it is embedded and disposed so as to protrude and protrude in the vicinity of the outer surface, the loop-like extra length 7B can be found and pulled out from the cable sheath 5 at the time of intermediate rear branching. That is, since the upper portion of the loop-like surplus portion 7B in FIG. 1B is embedded in the immediate vicinity of the outer surface of the cable sheath 5, that is, in the outermost surface of the cable sheath 5, the needle-like extra portion 7B The loop-like surplus portion 7B can be easily pulled out with a simple tool.

  Therefore, the cable sheath 5 can be easily torn by pulling the lip cord 7 without scraping off the cable sheath 5, and there is no trouble and the possibility of damaging the optical fiber inside the cable core 3 can be greatly reduced.

  Further, the raised portion 7C in the vicinity of the outer surface of the cable sheath 5 is raised in the vicinity of the outer surface of the cable sheath 5 with an extra length that can be easily pulled out. Since the lip cord 7 is connected to the outer surface of the cable core 3, that is, the sheath tearing portion 7A, the cable sheath 5 can be easily cut.

  When this tearing operation is performed at two locations on the left and right sides of the optical fiber cable 1 in FIG. 1A, the cable sheath 5 of the optical fiber cable 1 is divided into two, from which the optical fiber in the cable core 3 can be easily separated. It can be taken out. Then, connection processing and repair processing are performed on optical fibers such as cable strands as appropriate.

  Moreover, since the loop-like surplus portion 7B is provided intermittently in the longitudinal direction of the cable sheath 5, the mechanical strength of the cable sheath 5 is hardly adversely affected.

  Further, the lip cord 7 is arranged so as to be apparently connected without leaving a gap in the longitudinal direction of the cable core 3 in a portion where the loop-like surplus portion 7B is continuous with the sheath tearing portion 7A. This is desirable in that the cable sheath 5 can be easily torn.

  In the first embodiment, the upper portion of the loop-like surplus portion 7B in FIG. 1B is arranged so as to be raised very close to the outer surface of the cable sheath 5, but the cable sheath 5 It may be exposed on the outer surface. In this case, the portion exposed on the outer surface of the cable sheath 5 can be extracted to easily pull out the loop-shaped surplus portion 7B.

  Further, referring to FIG. 2, as another embodiment of the loop-like surplus length portion 7B, the lip cord 7 on the upper side of FIG. Is formed. That is, the apex portion of the “inverted triangle shape” is continuous with the sheath tearing portion 7A of the lip cord 7, and the bottom portion of the “inverted triangle shape” is exposed on the outer surface of the cable sheath 5 as the exposed portion 7D. . Therefore, the exposed portion 7D exposed on the outer surface of the cable sheath 5 can be easily picked out. Thereafter, the operation of tearing the cable sheath 5 by the lip cord 7 is the same as that in the case of “E” in FIG.

  The bottom portion of the “inverted triangular shape” is located near the outer surface of the cable sheath 5 as the raised portion 7C, as in the case of the “E-shaped” loop-like extra length portion 7B. It can also be arranged to be raised.

  Further, referring to FIG. 3, as another embodiment of the loop-like surplus portion 7B, the lip cord 7 on the upper side of FIG. The tip portion of the cable sheath 5 is exposed on the outer surface of the cable sheath 5. Therefore, the exposed portion 7D exposed on the outer surface of the cable sheath 5 can be easily pulled out by hooking it with a thin tool having a curved hook shape, for example. Thereafter, the operation of tearing the cable sheath 5 by the lip cord 7 is the same as that of the “E” shape in FIG.

  In addition, as an embodiment of the loop-shaped surplus portion 7B, as shown in FIG. 1 (B), “E-shape”, as shown in FIG. 2, “inverted triangle shape”, As shown in FIG. 3, the present invention is not limited to the “super elliptical shape” or the “folded shape”, and may be various other loop shapes.

  Next, as a self-supporting type (SS type) optical fiber cable 9 according to the second embodiment of the present invention, as shown in FIG. 4, a tensile body 11 (for example, seven steel wires) as a hanging line is used. A long cable support wire portion 15 in which the periphery of a twisted steel stranded wire is covered with a sheath resin 13 is provided. The cable support wire portion 15 is connected to the optical fiber cable 1 via a neck portion 17. They are integrated in parallel with each other.

  In addition, since the effect | action and effect of the optical fiber cable 9 of 2nd Embodiment are the same as that of the optical fiber cable 1 of 1st Embodiment mentioned above, detailed description is abbreviate | omitted.

  Next, an optical fiber cable 19 according to a third embodiment of the present invention will be described. The same members as those of the optical fiber cable 1 of the first embodiment described above will be described with the same reference numerals, and only different portions will be mainly described.

  5A and 5B, a portion different from the optical fiber cable 1 of the first embodiment is a lip cord. That is, in the upper part of FIG. 5B, a lip cord assembly portion 25 formed by combining two first and second lip cords 21 and 23 is embedded in the cable sheath 5. One first lip cord 21 is disposed on the outer surface of the cable core 3 in the longitudinal direction, and is intermittently disposed in the longitudinal direction on the first inner surface portion 21A. And a first outer surface portion 21B which becomes the extra length portion. The other second lip cord 23 includes a second inner surface portion 23A serving as a sheath tearing portion attached to the outer surface of the cable core 3 in the longitudinal direction, and intermittently extending in the longitudinal direction to the second inner surface portion 23A. It has the 2nd outer surface part 23B used as the extra length part arranged automatically.

  The two first and second lip cords 21 and 23 are combined so as to be attached to the outer surface of the cable core 3 on the same line extending in the longitudinal direction thereof, and the first and second outer surface portions 21B are combined. , 23B are alternately arranged in the longitudinal direction of the cable sheath 5, and the first and second outer surface portions 21 B, 23 B of the two first and second lip cords 21, 23 are the thickness of the cable sheath 5. The first and second outer surface portions 21B and 23B are arranged in such a manner that their upper portions are raised in the vicinity of the outer surface of the cable sheath 5 in FIG. 5B.

  For example, each of the first and second lip cords 21 and 23 is in the thickness direction of the cable sheath 5 (the cable sheath 5 with respect to the first and second inner surface portions 21A and 23A along the outer surface of the cable core 3. The first and second outer surface portions 21B and 23B that are continuous with the first and second inner surface portions 21A and 23A are intermittently provided. In this case, the “extra length portion” which is the first and second outer surface portions 21B and 23B is not formed in a loop shape, and is different from the “loop surplus length portion” of the first embodiment described above. ing.

  Further, the two first and second lip cords 21 and 23 are, for example, a rising portion of the first outer surface portion 21B (or the second outer surface portion 23B) and the first outer surface portion 21B (or the second outer surface portion 23B). Crossing at the lowering portion, the sheath first inner surface portion 21A (or second inner surface portion 23A) of one first lip cord 21 (or second lip cord 23) and the other second lip cord 23 (or second lip cord 23) The second outer surface portion 23 </ b> B (or the first outer surface portion 21 </ b> B) of the one lip cord 21 is disposed so as to face the outer surface and the inner surface of the cable sheath 5 at the same position in the longitudinal direction of the cable sheath 5.

  In the third embodiment, in the cable sheath 5, the lip cord assembly portion 25 combined with the two first and second lip cords 21, 23 is substantially the same as the cable core 3. On the line passing through the center, the cable core 3 is disposed so as to be opposed to both sides of the cable core 3 so as to be substantially parallel to the longitudinal direction of the cable core 3, and at least one set of the first and second lip cords 21, It is only necessary that 23 are arranged, and three or more sets of lip cords 21 and 23 may be arranged, and the present invention is not limited thereto.

  Next, a method of intermediate post branching of the optical fiber cable 19 will be described. As shown in FIGS. 5 (A) and 5 (B), the first of the two first and second lip cords 21 and 23 is divided into a so-called intermediate rear branch portion that branches in the middle of the optical fiber cable 19. The second outer surface portions 21B and 23B are alternately raised in the vicinity of the outer surface of the cable sheath 5 along the longitudinal direction of the cable sheath 5 to form the raised portions 21C and 23C. One or both of the raised portions 21C and 23C of the first and second outer surface portions 21B and 23B can be easily taken out and pulled only with a simple needle-like tool, for example.

  Therefore, as in the first embodiment described above, the cable sheath 5 can be easily torn by pulling the first lip cord 21 without scraping the cable sheath 5, and there is no trouble and the inside of the cable core 3. The possibility of damaging the optical fiber can be greatly reduced.

  In addition, since the two first and second lip cords 21 and 23 are alternately continuous at the first and second inner surface portions 21A and 23A attached to the outer surface of the cable core 3, for example, 2 The cable sheath 5 can be easily torn to a desired length by simultaneously pulling the first and second outer surface portions 21B and 23B of the first and second lip cords 21 and 23 of the book.

  When this tearing operation is performed at two positions on the left and right sides of the optical fiber cable 19 in FIG. 5A, the cable sheath 5 of the optical fiber cable 19 is divided into two, from which the optical fiber in the cable core 3 can be easily formed. It can be taken out. Then, connection processing and repair processing are performed on optical fibers such as cable strands as appropriate.

  In addition, since the first and second outer surface portions 21B and 23B are intermittently provided in the longitudinal direction of the cable sheath 5, the mechanical strength of the cable sheath 5 is hardly adversely affected.

  In the third embodiment, the upper portions of the first and second outer surface portions 21B and 23B in FIG. 5B are arranged so as to be raised very close to the outer surface of the cable sheath 5. The cable sheath 5 may be exposed on the outer surface. In this case, it is possible to easily pull out the extra length portions 21B and 23B by picking out the portion exposed on the outer surface of the cable sheath 5.

  Next, as a self-supporting type (SS type) optical fiber cable 27 according to the fourth embodiment of the present invention, as shown in FIG. 6, a tensile strength member 11 (for example, seven steel wires) as a suspension line is used. A long cable support wire portion 15 having a periphery of a twisted steel stranded wire) covered with a sheath resin 13 is provided. The cable support wire portion 15 is connected to the optical fiber cable 19 via a neck portion 17. They are integrated in parallel with each other.

  In addition, since the effect | action and effect of the optical fiber cable 27 of 4th Embodiment are the same as that of the optical fiber cable 19 of 3rd Embodiment mentioned above, detailed description is abbreviate | omitted.

  From the above, in any of the optical fiber cables 1, 9, 19, 27 of any of the embodiments, the lip cord 7, the first and second lip cords 21, 23 are intermittently exposed on the outer surface of the cable sheath 5. Alternatively, the portion can be easily taken out by being raised. By further pulling the lip cord 7 and the first and second lip cords 21 and 23 taken out, the cable sheath 5 can be easily torn and the optical fiber in the cable core 3 can be easily taken out. In particular, this is effective for intermediate post branching.

(A) is a cross section orthogonal to the longitudinal direction of the optical fiber cable of the first embodiment of the present invention, in particular, a cross sectional view taken along the line IA-IA in (B). It is sectional drawing of arrow IB-IB. It is sectional drawing which shows other embodiment of the lip cord of FIG. It is sectional drawing which shows other embodiment of the lip cord of FIG. It is sectional drawing orthogonal to the longitudinal direction of the self-supporting type optical fiber cable of 2nd Embodiment of this invention. (A) is a cross section orthogonal to the longitudinal direction of the optical fiber cable of the third embodiment of the present invention, in particular, a cross-sectional view taken along the arrow VA-VA of (B). It is sectional drawing of arrow VB-VB. It is sectional drawing orthogonal to the longitudinal direction of the self-supporting type optical fiber cable of the 4th Embodiment of this invention. It is sectional drawing of the conventional optical fiber cable. It is sectional drawing of the other conventional self-supporting type optical fiber cable.

Explanation of symbols

1 Optical fiber cable (of the first embodiment)
3 Cable core 5 Cable sheath (jacket)
7 Lip cord (tear string)
7A Sheath tear part 7B Loop-like extra length part 7C Raised part 7D Exposed part 9 Self-supporting optical fiber cable (of the second embodiment)
DESCRIPTION OF SYMBOLS 11 Strength body 13 Sheath resin 15 Cable support line part 17 Neck part 19 Optical fiber cable (of 3rd Embodiment)
21 first lip cord 21A first inner surface portion 21B first outer surface portion 21C raised portion 23 second lip cord 23A second inner surface portion 23B second outer surface portion 23C raised portion 25 lip cord assembly portion 27 self-supporting Type optical fiber cable (in the fourth embodiment)

Claims (2)

In an optical fiber cable having a cable core containing an optical fiber and a cable sheath coated on the outer periphery of the cable core,
At least one lip cord is embedded in the cable sheath so as to extend in the longitudinal direction of the cable sheath, and the lip cord is intermittently looped in the longitudinal direction of the lip cord in the thickness direction of the cable sheath. An extra length portion is formed and embedded in the cable sheath, and a part of each loop-like extra length portion is exposed on the outer surface of the cable sheath or protrudes in the vicinity of the outer surface of the cable sheath. An optical fiber cable characterized by being arranged as described above. In an optical fiber cable having a cable core containing an optical fiber and a cable sheath coated on the outer periphery of the cable core,
First lip cords extending in the longitudinal direction of the cable sheath are alternately arranged on a first inner surface portion located on the inner surface side of the cable sheath and a first outer surface portion located on the outer surface side of the cable sheath. And the 2nd inner surface part and the 1st lip cord which the 2nd lip cord extended in the longitudinal direction of the cable sheath is located in the inner surface side of the cable sheath corresponding to the 1st outer surface part of the 1st lip cord The second outer surface portion located on the outer surface side of the cable sheath corresponding to the first inner surface portion of the cable sheath is alternately arranged and embedded in the cable sheath,
The first outer surface portion of the first lip cord and the second outer surface portion of the second lip cord are arranged so as to be exposed on the outer surface of the cable sheath or protrude in the vicinity of the outer surface of the cable sheath. An optical fiber cable characterized by

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