JP2011169937A - Optical fiber ribbon and optical fiber cable - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for attaining smaller diameter and higher density of an optical fiber cable which accepts an optical fiber ribbon, and for facilitating a branching work, after middle section. <P>SOLUTION: The optical fiber ribbon has 2N (N: integer of 2 or larger) cores of optical fibers arranged in parallel, and adjacent optical fibers intermittently connected in the longitudinal direction, wherein a pair of optical fibers consisting of the optical fiber of the (2n-1)-th from one end side of the tape width direction and an optical fiber of the 2n-th (n: natural number which is not larger than N) are connected by a first connection parts of L1 in length provided at interval S1. Furthermore, a pair of optical fibers consisting of the optical fiber of the 2m-th from one end side of the tape width direction and an optical fiber of the (2m+1)-th (m: natural number which is not larger than (N-1)) are connected by a second connection parts of L2 in length provided at interval S2 such that L1, S1, and L2, S2 satisfy the relations: L1>S1 and L2<S2. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical fiber ribbon and an optical fiber cable that accommodates the optical fiber ribbon.

In recent years, with the widespread use of the Internet, FTTH (Fiber To The Home) that realizes a high-speed communication service by drawing an optical fiber directly into a general home is rapidly expanding. In general, a plurality of optical fiber ribbons (hereinafter referred to as tape ribbons) are bundled and accommodated in an optical fiber cable used for FTTH. When an optical fiber is pulled down from this optical fiber cable to the FTTH user's home, it is necessary to branch the optical fiber cable in the middle to take out a desired tape core wire and to separate the single core wire from the tape core wire. .
Therefore, various types of tape core wires have been proposed in order to easily separate single cores and to reduce the diameter and density of optical fiber cables. For example, in Patent Documents 1 and 2, adjacent optical fibers are intermittently connected in the longitudinal direction, and are alternately arranged so that the connecting portions adjacent in the tape width direction do not overlap.
In this way, the adjacent optical fibers are intermittently connected to each other in the longitudinal direction to form a tape core, so that the shape easily changes when a plurality of tape cores are bundled. Increase in density and density. Further, since there is a non-connected portion in the tape core wire, the single core can be separated relatively easily without using a dedicated tool.

Japanese Patent Laid-Open No. 2003-232297 Japanese Patent No. 4143651

However, in the tape core described in Patent Document 1 described above, there are two-core unit portions or unconnected single-core wire portions in the tape width direction, but both have short lengths. When bundled, it shows almost the same behavior as a multi-core ribbon. That is, since the part of a unit of 2 cores or the part of a single core wire cannot move freely, a big shape change cannot be expected. Therefore, the effect of reducing the diameter of the optical fiber cable is low.
Moreover, in the tape core wire described in Patent Document 2, the length of the connecting portion connecting adjacent optical fibers is short and the length of the non-connecting portion is long. It shows almost the same behavior as the line. That is, there are few parts where the single core wire is restrained, and it moves freely more than necessary. Therefore, it becomes easy for individual optical fibers to be pulled out from the tape core with a single core, and when taking out the tape core from the optical fiber cable, the single core is picked up to increase loss, or the tape core is fused together. When setting to the fusion holder for connection, there is a problem that the core wire arrangement is changed.

  It is an object of the present invention to provide a technique that can reduce the diameter and increase the density of an optical fiber cable that accommodates a tape core, and can facilitate an intermediate post branching operation.

The invention described in claim 1 is made in order to achieve the above object, wherein 2N (N: integer of 2 or more) core optical fibers are arranged in parallel, and adjacent optical fibers are intermittent in the longitudinal direction. An optical fiber ribbon connected to
An optical fiber pair consisting of a (2n-1) -th optical fiber and a 2n-th optical fiber (n: a natural number equal to or less than N) from one end in the tape width direction is a first connection having a length L1 provided at an interval S1. Linked by parts,
An optical fiber pair consisting of a 2m-th optical fiber and a (2m + 1) -th optical fiber (m: natural number less than (N-1)) from one end side in the tape width direction has a length L2 of the length L2 provided at the interval S2. Connected by two connecting parts,
The L1, S1, L2, and S2 satisfy L1> S1 and L2 <S2.

  According to a second aspect of the present invention, in the optical fiber ribbon according to the first aspect, the interval S1 is 15 mm or more and 50 mm or less.

  According to a third aspect of the invention, in the optical fiber ribbon according to the first or second aspect, the interval S2 is 100 mm or more and 500 mm or less.

The invention according to claim 4 is the optical fiber ribbon according to any one of claims 1 to 3, wherein the first connecting portions are arranged at the same position in the tape width direction.
The second connecting part is arranged so as not to overlap the first connecting part in the tape width direction.

  According to a fifth aspect of the present invention, an optical fiber cable is formed by covering an outer periphery of a cable core housing the optical fiber ribbon according to any one of the first to fourth aspects. It is.

  ADVANTAGE OF THE INVENTION According to this invention, while being able to achieve diameter reduction and density increase of the optical fiber cable which accommodated the optical fiber tape core wire, intermediate | middle post branching work can be made easy.

It is a top view which shows the connection state of the tape core wire which concerns on 1st Embodiment. It is sectional drawing in the arbitrary positions of the longitudinal direction of the tape core wire which concerns on 1st Embodiment. It is a figure which shows the evaluation result of the tape core wire which concerns on Example 1,2. It is a top view which shows the connection state of the tape core wire which concerns on 2nd Embodiment. It is sectional drawing in the arbitrary positions of the longitudinal direction of the tape core wire which concerns on 2nd Embodiment. It is a figure which shows the evaluation result of the tape core wire which concerns on Examples 3-7. It is a figure which shows an example of the arrangement pattern of the connection part in an 8-core tape core wire. It is a figure which shows another example of the arrangement pattern of the connection part in an 8-core tape core wire. It is a figure which shows another example of the arrangement pattern of the connection part in an 8-core tape core wire. It is a figure which shows another example of the arrangement pattern of the connection part in an 8-core tape core wire. It is a figure which shows another example of the arrangement pattern of the connection part in an 8-core tape core wire. It is a figure which shows another example of the arrangement pattern of the connection part in an 8-core tape core wire.

Hereinafter, embodiments of the present invention will be described in detail.
[First Embodiment]
FIG. 1 is a plan view showing a connection state of optical fiber ribbons according to the first embodiment, and FIG. 2 is a cross-sectional view at an arbitrary position in the longitudinal direction. FIG. 2 shows cross sections (A-A cross-section, BB cross-section, and CC cross-section in FIG. 1) seen at three locations in the longitudinal direction.
As shown in FIGS. 1 and 2, an optical fiber ribbon (hereinafter referred to as “tape ribbon”) 1 is a four-core optical fiber (having a minimum protective coating around the optical fiber, hereinafter, Optical fibers) 11 to 14 are arranged in parallel, and two adjacent optical fibers are intermittently connected in the longitudinal direction.

More specifically, a pair of optical fibers P1 including the first optical fiber 11 and the second optical fiber 12 from one end side (for example, the upper side in FIG. 1) in the tape width direction is a first L1 of length L1. The connection part 21 is intermittently connected in the longitudinal direction. In the optical fiber pair P1, a plurality of first connecting portions 21 (appearing at three places in FIG. 1) are provided at equal intervals at an interval S1. That is, in the optical fiber pair P1, the length of the unconnected portion 31 is S1. The same applies to the optical fiber pair P3 including the third optical fiber 13 and the fourth optical fiber 14 from one end side in the tape width direction.
In these two pairs of optical fibers P1 and P3, the first connecting portion 21 is provided so that the arrangement in the tape width direction is the same. Accordingly, the unconnected portions 31 of the two pairs of optical fibers P1 and P3 also coincide with each other in the tape width direction.

Further, the optical fiber pair P2 including the second optical fiber 12 and the third optical fiber 13 from one end side in the tape width direction is intermittently connected in the longitudinal direction by the second connecting portion 22 having a length L2. . In the optical fiber pair P2, a plurality of second connecting portions 22 (appearing at two places in FIG. 1) are provided at equal intervals at an interval S2. That is, in the optical fiber pair P2, the length of the non-connecting portion 32 is S2.
In addition, the 1st connection part 21 and the 2nd connection part 22 are formed by apply | coating and hardening a well-known adhesive resin, such as an ultraviolet curable resin and a thermosetting resin, for example in a predetermined pattern.

Here, in the optical fiber pair P1, P3, each length is designed so that the length L1 of the first connecting portion 21 is longer than the length S1 of the non-connecting portion 31. Since the optical fibers 11 and 14 positioned outside are more likely to protrude from the optical fiber ribbon 1 as compared with the adjacent optical fibers, at least L1> S1 is set in order to prevent the optical fibers 11 and 14 from protruding.
Preferably, the length S1 of the unconnected portion 31 is set to 15 mm or more and 50 mm or less. By setting the length S1 of the non-connecting portion 31 to 15 mm or more, only the desired optical fiber can be easily selected and taken out when the outer optical fibers 11 and 14 are separated from each other. The line takeout property is improved. Moreover, since it becomes difficult for a single core wire to protrude from the optical fiber tape core wire 1 by setting the length S1 of the non-connecting portion 31 to 50 mm or less, there is no possibility that the core wire arrangement may be replaced, and at the time of batch fusion connection Workability is improved.
In addition, by setting the length L1 of the first connecting portion 21 to 500 mm or less, the unconnected portion 31 always appears from the tearing portion in the intermediate post-branching operation of the optical fiber cable, so that the single core wire can be taken out more easily.

Further, in the optical fiber pair P2, each length is designed so that the length L2 of the second connecting portion 22 is shorter than the length S2 of the non-connecting portion 32. Since the optical fibers 12 and 13 are connected to two adjacent optical fibers, the length L2 of the second connecting portion 22 may be set so as to be able to hold the core wire arrangement so as not to be replaced. Therefore, considering the workability when separating the single cores 13 and the diameter reduction when bundled, it is desirable to lengthen the length S2 of the unconnected portion 32 to some extent, so at least L2 <S2.
Preferably, the length S2 of the unconnected portion 32 is set to 100 mm or more and 500 mm or less. By setting the length S2 of the non-connecting portion 32 to 100 mm or more, the portion connected in units of two cores becomes sufficiently long, so that the diameter when bundled can be reduced. In addition, by setting the length S2 of the non-connecting portion 32 to 500 mm or less, the second connecting portion 22 always appears from the split portion in the intermediate post-branching operation of the optical fiber cable. Easy workability at the time of batch fusion splicing.

  Furthermore, in the first embodiment, the second connecting portion 22 in the optical fiber pair P2 is not overlapped with the first connecting portions 21 of the two optical fiber pairs P1 and P3 in the tape width direction, in other words, the non-connecting portion. 31 is provided at a position corresponding to 31. That is, the length S1 of the unconnected portion 31 of the optical fiber pair P1, P3 is designed to be longer than the length L2 of the second connecting portion 22 of the optical fiber pair P2.

  The connection state in the tape width direction of the tape core wire 1 having the above-described structure is a state in which the two-core unit connection portions shown in FIG. 2 (a) form two sets, and the two-core unit connection state shown in FIG. 2 (b). It becomes either a state where the parts are one set, or a state where the four cores shown in FIG. 2C are not connected. That is, the tape core wire 1 is connected in units of a maximum of 2 cores in the longitudinal direction.

[Example]
In Examples 1 and 2, the dimensions of the tape core wire 1 according to the first embodiment were determined so as to satisfy L1> S1 and L2 <S2.
In the first embodiment, the length L1 of the first connecting portion 21 in the optical fiber pair P1, P3 is 200 mm, the length S1 of the non-connecting portion 31 is 30 mm, and the length L2 of the second connecting portion 22 in the optical fiber pair P2 is used. Was 10 mm, and the length S2 of the unconnected portion 32 was 220 mm.
In the second embodiment, the length L1 of the first connecting portion 21 in the optical fiber pair P1, P3 is 400 mm, the length S1 of the non-connecting portion 31 is 50 mm, and the length L2 of the second connecting portion 22 in the optical fiber pair P2 is used. Was 20 mm, and the length S2 of the unconnected portion 32 was 430 mm.

[Comparative example]
In Comparative Example 1, the length L1 of the first connecting portion 21 in the optical fiber pair P1, P3, the length S1 of the non-connecting portion 31, the length L2 of the second connecting portion 22 in the optical fiber pair P2, and the non-connecting portion 32. The length S2 of all was 50 mm.
In Comparative Example 2, the length L1 of the first connecting portion 21 in the optical fiber pair P1, P3 is 15 mm, the length S1 of the non-connecting portion 31 is 100 mm, and the length L2 of the second connecting portion 22 in the optical fiber pair P2. Was 15 mm, and the length S2 of the unconnected portion 32 was 100 mm.

For the tape cores of Examples 1 and 2 and Comparative Examples 1 and 2 described above, (1) diameter reduction when bundled, (2) take-out property of the tape core, (3) replacement of the core array, 4) Four items of single wire takeout were evaluated.
In the evaluation item (1), assuming the state accommodated in the optical fiber cable, the state of the bundle in the longitudinal direction when the five tape core wires were bundled was observed. And, the case where it is the same as the state where the four-core-coated tape core wires are laminated (hereinafter, the 4-core collective state) is changed to X, an arbitrary shape (the 4-core collective state exists in a part of the longitudinal direction) The case was evaluated as ○, and the case where the shape was changed to an arbitrary shape (no state of four cores in the longitudinal direction) was evaluated as ◎.
In evaluation item (2), assuming an intermediate post-branching operation of an optical fiber cable, when taking out a desired tape core from a state in which five tape cores are bundled, pick a single core other than the tape core. I examined whether it was put out. Then, the case where a single core wire other than the desired tape core wire was picked up was evaluated as x, and the case where it was not evaluated was evaluated as ◯.
In the evaluation item (3), assuming the work of the fusion bonding connection of the tape core wires, the state of the core wire array when it was set in the fusion holder while aligning the core wire arrays of the tape core wires was examined. Then, the case where there was a change in the core arrangement was evaluated as x, and the case where there was no change was evaluated as ◯.
In the evaluation item (4), an intermediate post-branching operation of the optical fiber cable was assumed, and it was examined whether or not a desired single core wire could be separated by hand at an arbitrary position of 500 mm in the longitudinal direction of the tape core wire. Then, the case where the single core could not be separated and taken out was evaluated as x, and the case where it could be taken out was evaluated as o.

  The evaluation results are shown in FIG. As shown in FIG. 3, in the tape cores of Examples 1 and 2, good results were obtained for all the evaluation items. On the other hand, in the tape core wire of Comparative Example 1, good results were not obtained in the evaluation of the diameter reduction when bundled. Since there are no single-core portions that are not connected in the tape width direction, and the lengths S1 and S2 of the non-connection portions 31 and 32 are both as short as 50 mm, they exhibit the same behavior as a 4-core tape core wire. It is thought. Moreover, in the tape core wire of Comparative Example 2, good results were not obtained in the evaluation of the take-out property of the tape core wire and the replacement of the core wire array. Because the lengths S1 and S2 of the non-connection portions 31 and 32 are remarkably longer than the lengths L1 and L2 of the connection portions 21 and 22, the individual optical fibers are easily pulled out of the tape cores as a single core. it is conceivable that.

  As described above, in the tape core wire 1 according to the first embodiment, an optical fiber pair including the (2n-1) th optical fiber and the 2nth optical fiber (n = 1, 2) from one end side in the tape width direction. P1 and P3 are connected by a first connecting portion 21 having a length L1 provided at an interval (the length of the non-connecting portion 31) S1. Also, an optical fiber pair P2 composed of the 2m-th optical fiber and the (2m + 1) -th optical fiber (m = 1) from one end side in the tape width direction is provided at the interval (length of the non-connecting portion 32) S2. It is connected by a second connecting portion 22 having a length L2. L1, S1, L2, and S2 satisfy L1> S1, L2 <S2.

According to the tape core wire 1, the portion connected in units of two cores (see FIG. 2 (a)) becomes long, so the shape changes compared to the optical fiber tape core wire coated in units of four cores. It is easy and effective in reducing the diameter when a plurality of tape cores are bundled. Also, since all single-core wires (see Fig. 2 (c)) are extremely short, when removing the tape core from the optical fiber cable, pinch the single core to increase the loss, It is possible to prevent the arrangement of the core wires from being changed when setting to the fusion holder for batch fusion connection. Furthermore, since there is a non-connecting portion in any optical fiber pair constituting the tape core wire, single-core separation can be easily performed without a tool.
Therefore, by using the tape core wire 1 according to the first embodiment, it is possible to reduce the diameter and increase the density of the optical fiber cable and to facilitate the intermediate post branching operation.

Further, since the length S1 of the non-connecting portion 31 and the length S2 of the non-connecting portion 32 satisfy 15 ≦ S1 ≦ 50 and 100 ≦ S2 ≦ 500, a small diameter when a plurality of tape cores are bundled. It is more effective to make the intermediate branching of the optical fiber cable easier.
Further, the second connecting portion 22 in the optical fiber pair P2 is provided so as not to overlap the first connecting portions 21 of the two pairs of optical fibers P1 and P3 in the tape width direction. As a result, a maximum of 2 core units can be connected in the longitudinal direction (there is no part where 3 or more cores are connected). It is.

[Second Embodiment]
FIG. 4 is a plan view showing a connection state of the optical fiber ribbons according to the second embodiment, and FIG. 5 is a cross-sectional view at an arbitrary position in the longitudinal direction. FIG. 5 shows cross sections (A-A cross-section, BB cross-section, and CC cross-section in FIG. 4) seen at three locations in the longitudinal direction. Note that the basic configuration of the tape core 2 according to the second embodiment is the same as that of the tape core 1 according to the first embodiment, and a description thereof will be omitted.

The tape core wire 2 according to the second embodiment differs from the tape core wire 1 according to the first embodiment in the location of the second connecting portion 22. Specifically, the second connecting portion 22 in the optical fiber pair P2 is provided so as to overlap the first connecting portions 21 of the two pairs of optical fibers P1 and P3 in the tape width direction.
The connection state of the tape core wires 2 having the above-described structure in the tape width direction is a state in which the connection is made in units of four cores shown in FIG. 5A, and there are two connection parts in units of two cores shown in FIG. The state becomes a pair, or the state of a single core wire in which none of the four cores shown in FIG. 5C are connected.

[Example]
In Examples 3 to 7, the dimensions of the optical fiber ribbon 2 according to the second embodiment were determined so as to satisfy L1> S1 and L2 <S2.
In Example 3, the length L1 of the first connecting portion 21 in the optical fiber pair P1, P3 is 100 mm, the length S1 of the non-connecting portion 31 is 15 mm, and the length L2 of the second connecting portion 22 in the optical fiber pair P2 is used. Was 15 mm, and the length S2 of the unconnected portion 32 was 100 mm.
In the fourth embodiment, the length L1 of the first connecting portion 21 in the optical fiber pair P1, P3 is 200 mm, the length S1 of the non-connecting portion 31 is 30 mm, and the length L2 of the second connecting portion 22 in the optical fiber pair P2 is used. Was 30 mm, and the length S2 of the unconnected portion 32 was 200 mm.
In Example 5, the length L1 of the first connecting portion 21 in the optical fiber pair P1, P3 is 400 mm, the length S1 of the non-connecting portion 31 is 50 mm, and the length L2 of the second connecting portion 22 in the optical fiber pair P2 is used. Was 50 mm, and the length S2 of the unconnected portion 32 was 400 mm.
In the sixth embodiment, the length L1 of the first connecting portion 21 in the optical fiber pair P1, P3 is 100 mm, the length S1 of the non-connecting portion 31 is 10 mm, and the length L2 of the second connecting portion 22 in the optical fiber pair P2. Was 10 mm, and the length S2 of the unconnected portion 32 was 100 mm.
In Example 7, the length L1 of the first connecting portion 21 in the optical fiber pair P1, P3 is 500 mm, the length S1 of the non-connecting portion 31 is 50 mm, and the length L2 of the second connecting portion 22 in the optical fiber pair P2 is used. Was 50 mm, and the length S2 of the unconnected portion 32 was 500 mm.

For the optical fiber ribbons of Examples 3 to 7 described above, four items were evaluated as in Examples 1 and 2. The evaluation results are shown in FIG. As shown in FIG. 6, in the optical fiber ribbons of Examples 3 to 5, good results were obtained for all the evaluation items although the diameter reduction when bundled was inferior to Examples 1 and 2. It was.
For the optical fiber ribbons of Examples 6 and 7, the evaluation of the single-core extraction property was x, but good results were obtained for other evaluation items. If the length S1 of the unconnected portion 31 in the optical fiber pair P1, P3 is as short as 10 mm as in the sixth embodiment, it is difficult to separate the outer optical fibers 11, 14 from each other. Further, as in the seventh embodiment, when the length L1 of the connecting portion 31 in the optical fiber pair P1, P3 is too long as 500 mm, the unconnected portion having a sufficient length in an arbitrary position 500 mm in the longitudinal direction of the tape core wire. The part 31 may not appear. However, Examples 6 and 7 also have a sufficient effect for reducing the diameter when bundled.

  Thus, in the tape core wire 2 according to the second embodiment, an optical fiber pair composed of the (2n-1) th optical fiber and the 2nth optical fiber (n = 1, 2) from one end side in the tape width direction. P1 and P3 are connected by a first connecting portion 21 having a length L1 provided at an interval (the length of the non-connecting portion 31) S1. Also, an optical fiber pair P2 composed of the 2m-th optical fiber and the (2m + 1) -th optical fiber (m = 1) from one end side in the tape width direction is provided at the interval (length of the non-connecting portion 32) S2. It is connected by a second connecting portion 22 having a length L2. L1, S1, L2, and S2 satisfy L1> S1, L2 <S2.

According to the tape core wire 2, since the portion connected in units of two cores (see FIG. 5B) becomes long, the shape changes as compared with the optical fiber tape core wire collectively coated in units of four cores. It is easy and effective in reducing the diameter when a plurality of tape cores are bundled. Also, since all single-core wires (see Fig. 5 (c)) are shortened, when removing the tape core from the optical fiber cable, the single-core is pinched to increase the loss, or the tape core is bundled together. When setting to the fusion holder for fusion connection, it is possible to prevent the core wire arrangement from being switched. Furthermore, since there is a non-connecting portion in any optical fiber pair constituting the tape core wire, single-core separation can be easily performed without a tool.
Therefore, by using the tape core wire 2 according to the second embodiment, it is possible to reduce the diameter and increase the density of the optical fiber cable and to facilitate the intermediate post branching operation.

  Further, if the length S1 of the non-connecting portion 31 and the length S2 of the non-connecting portion 32 satisfy 15 ≦ S1 ≦ 50 and 100 ≦ S2 ≦ 500, the fineness when bundling a plurality of tape cores is bundled. This is more effective for facilitating the diameter branching and the intermediate branching work of the optical fiber cable.

As mentioned above, although the invention made by this inventor was concretely demonstrated based on embodiment, this invention is not limited to the said embodiment, It can change in the range which does not deviate from the summary.
For example, in the above-described embodiment, the 4-fiber ribbon is described. However, in the present invention, 2N (N: integer of 2 or more) optical fibers are arranged in parallel, and adjacent optical fibers are intermittently connected in the longitudinal direction. It can be applied to the optical fiber ribbon. And the arrangement pattern of the 1st connection part 21 and the 2nd connection part 22 is diversified as the number of the optical fiber which comprises a tape core wire increases. For example, any pattern shown in FIGS. 7 to 12 satisfies the requirements defined in the present invention.

7-9 is a figure which shows an example of the connection state of the 8-core tape core wire corresponding to the 4-core tape core wire 1 which concerns on 1st Embodiment. That is, in the tape core wires 3 to 5 shown in FIGS. 7 to 9, the second connecting portion 22 is provided so as not to overlap the first connecting portion 21.
As shown in FIG. 7, in the tape core wire 3, an optical fiber composed of a (2n-1) th optical fiber and a 2nth optical fiber (n = 1, 2, 3, 4) from one end side in the tape width direction. The pairs P1, P3, P5, and P7 are connected by a first connecting portion 21 having a length L1 provided at an interval (the length of the non-connecting portion 31) S1. Further, optical fiber pairs P2, P4, and P6 composed of the 2m-th optical fiber and the (2m + 1) -th optical fiber (m = 1, 2, 3) from one end side in the tape width direction are spaced apart from each other (of the unconnected portion 32). It is connected by a second connecting portion 22 having a length L2 provided at length S2. L1, S1, L2, and S2 satisfy L1> S1, L2 <S2.
Further, in the optical fiber pairs P1, P3, P5, and P7, the first connecting portion 21 is provided so that the arrangement in the tape width direction is the same. Accordingly, the unconnected portions 31 of the optical fiber pairs P1, P3, P5, and P7 also coincide with each other in the tape width direction. The second connecting portions 22 in the optical fiber pairs P2, P4, and P6 do not overlap the first connecting portions 21 of the optical fiber pairs P1, P3, P5, and P7 in the tape width direction, in other words, the non-connecting portions 31. And are provided at corresponding positions.

The basic configuration of the tape core 4 shown in FIG. 8 and the tape core 5 shown in FIG. 9 is the same as that of the tape core 3 described above, and the arrangement pattern of the second connecting portions 22 is different.
That is, in the tape core wire 3 shown in FIG. 7, the second connecting portions 22 in the optical fiber pairs P2, P4, and P6 are provided so that the arrangement in the tape width direction is the same.
8, the arrangement of the second connecting portions 22 in the optical fiber pairs P2, P4, P6 is shifted in the longitudinal direction, and the unconnected portions 31 of the optical fiber pairs P1, P3, P5, P7 One or two second connecting portions 22 appear alternately at the corresponding positions.
In the tape core wire 5 shown in FIG. 9, the arrangement of the second connecting portions 22 in the optical fiber pairs P2, P4, and P6 is shifted in the longitudinal direction, and the unconnected portions 31 of the optical fiber pairs P1, P3, P5, and P7 and Only one second connecting portion 22 appears at the corresponding position.
According to the above-described tape cores 3 to 5, similar to the tape core 1 shown in the embodiment, it is possible to reduce the diameter and increase the density of the optical fiber cable and facilitate the intermediate post branching operation. can do.

  FIGS. 10-12 is a figure which shows an example of the connection state of the 8-core tape core wire corresponding to the 4-core tape core wire 2 which concerns on 2nd Embodiment. That is, in the tape core wires 6 to 8 shown in FIGS. 10 to 12, the second connecting portion 22 is provided so as to overlap the first connecting portion 21.

As shown in FIG. 10, in the tape core 6, an optical fiber composed of a (2n−1) th optical fiber and a 2nth optical fiber (n = 1, 2, 3, 4) from one end side in the tape width direction. The pairs P1, P3, P5, and P7 are connected by a first connecting portion 21 having a length L1 provided at an interval (the length of the non-connecting portion 31) S1. Further, optical fiber pairs P2, P4, and P6 composed of the 2m-th optical fiber and the (2m + 1) -th optical fiber (m = 1, 2, 3) from one end side in the tape width direction are spaced apart from each other (of the unconnected portion 32). It is connected by a second connecting portion 22 having a length L2 provided at length S2. L1, S1, L2, and S2 satisfy L1> S1, L2 <S2.
Further, in the optical fiber pairs P1, P3, P5, and P7, the first connecting portion 21 is provided so that the arrangement in the tape width direction is the same. Accordingly, the unconnected portions 31 of the optical fiber pairs P1, P3, P5, and P7 also coincide with each other in the tape width direction. And the 2nd connection part 22 in optical fiber pair P2, P4, P6 respond | corresponds to the position which overlaps with the 1st connection part 21 of optical fiber pair P1, P3, P5, P7 in the tape width direction, for example, the 1st connection part 21. In the center of the position to be placed, the arrangement in the tape width direction is the same.

The tape core 7 shown in FIG. 11 and the tape core 8 shown in FIG. 12 are also the same as the tape core 6 shown in FIG. 10 in that the first connecting portion 21 and the second connecting portion 22 are provided so as to overlap each other. It is.
In the tape core wire 7 shown in FIG. 11, the first connection portion 21 and the second connection portion 22 are provided in line symmetry with respect to the central optical fiber pair P4. Specifically, in the optical fiber pairs P1 and P7, the first connecting portions 21 are provided at equal intervals. In the optical fiber pairs P2 and P6, the second connecting portion 22 is provided at substantially the center of the position corresponding to the first connecting portion 21 of the optical fiber pairs P1 and P7. In the optical fiber pairs P3 and P5, the first connecting portion 21 is provided at a position corresponding to the non-connecting portion 32 of the optical fiber pairs P2 and P6. In the optical fiber pair P4, the second connecting portion 22 is provided at substantially the center of the position corresponding to the first connecting portion 21 of the optical fiber pairs P3 and P5.

In the tape core wire 8 shown in FIG. 12, the first connecting portion 21 and the second connecting portion 22 arranged in the tape width direction are gradually shifted in the longitudinal direction. Specifically, in the optical fiber pair P1, the first connection portions 21 are provided at equal intervals, and in the optical fiber pair P2, the first connection portion 21 is located at one end side of the position corresponding to the first connection portion 21 of the optical fiber pair P1. Two connecting portions 22 are provided. In the optical fiber pair P3, the first connection part 21 is provided at a position corresponding to the non-connection part 32 of the optical fiber pair P2. In the optical fiber pair P4, the first connection part 21 corresponds to the first connection part 21 of the optical fiber pair P3. The 2nd connection part 22 is provided in the one end side of the position. In the optical fiber pair P5, the first connecting portion 21 is provided at a position corresponding to the non-connecting portion 32 of the optical fiber pair P4. In the optical fiber pair P6, the first connecting portion 21 corresponds to the first connecting portion 21 of the optical fiber pair P5. The 2nd connection part 22 is provided in the one end side of the position. And in the optical fiber pair P7, the 1st connection part 21 is provided in the position corresponding to the non-connection part 32 of the optical fiber pair P6.
According to the above-described tape cores 6 to 8, as with the tape core 2 shown in the embodiment, it is possible to reduce the diameter and increase the density of the optical fiber cable and facilitate the intermediate post branching operation. can do.

  As the optical fiber cable according to the present invention, an optical fiber cable such as a center tube type, a loose tube type, and a slot type is conceivable, and the outer periphery of the cable core containing the optical fiber ribbon is covered with a jacket. The optical fiber cable is not particularly limited.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 Optical fiber tape core wire 11-14 Optical fiber P1-P3 Optical fiber pair 21 1st connection part 22 2nd connection part 31, 32 Non-connection part

Claims (5)

2N (N: integer greater than or equal to 2) optical fibers are arranged in parallel, and adjacent optical fibers are intermittently connected in a longitudinal direction,
An optical fiber pair consisting of a (2n-1) -th optical fiber and a 2n-th optical fiber (n: a natural number equal to or less than N) from one end in the tape width direction is a first connection having a length L1 provided at an interval S1. Linked by parts,
An optical fiber pair consisting of a 2m-th optical fiber and a (2m + 1) -th optical fiber (m: natural number less than (N-1)) from one end side in the tape width direction has a length L2 of the length L2 provided at the interval S2. Connected by two connecting parts,
L1, S1, L2, and S2 satisfy L1> S1, L2 <S2, and the optical fiber ribbon.   The optical fiber tape core wire according to claim 1, wherein the interval S1 is 15 mm or more and 50 mm or less.   3. The optical fiber ribbon according to claim 1, wherein the distance S <b> 2 is not less than 100 mm and not more than 500 mm. The first connecting portion is disposed at the same position in the tape width direction,
The optical fiber tape core wire according to any one of claims 1 to 3, wherein the second connecting portion is disposed so as not to overlap the first connecting portion in the tape width direction.   An optical fiber cable, wherein an outer periphery of a cable core containing the optical fiber ribbon according to any one of claims 1 to 4 is covered with a jacket.

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