JP2000039524A - Optical fiber holding structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an optical fiber holding structure capable of easily and exactly achieving the optical fiber holding processing to fix the optical fibers taken out of the slots of a spacer exposed by peeling sheaths to the outer periphery of the spacer. SOLUTION: The fiber holding tubes 23 of a fiber holding member 20, which is integrally provided in juxtaposition with a plurality of the fiber holding tubes 23 according to the arraying pitch of the slots 4 on the spacer 5 forming the optical fiber cable 1 on the other surface of ribbon parts 21 formed with tacky adhesive layers on one side, are inserted into the optical fibers 8 taken out of the slots 4. The fiber holding member 20 are wound around the outer peripheral of the spacer 5 via the tacky adhesive layers by aligning the fiber holding tubes 23 onto the slits 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber holding structure, and more particularly, to an optical fiber cable which is removed from a slot of an exposed spacer by stripping an outer jacket for connection processing in a connection box. The present invention relates to an optical fiber holding structure for fixing an optical fiber so that the arrangement on the spacer is not disturbed.

[0002]

2. Description of the Related Art As an optical fiber cable, there is a spacer type optical fiber cable in which an optical fiber is accommodated in a plurality of slots formed on the outer peripheral surface of a spacer and the outer peripheral surface of the spacer is covered with a jacket. Note that a tension member is provided on the shaft core of the spacer.

[0003] When such optical fiber cables are connected in a junction box, each optical fiber cable must be
Cut the jacket over a predetermined length to expose the spacer, and cut the tip of the spacer to an appropriate length,
Leave the tension member exposed. Then, after fixing the tension members in the connection box, the optical fibers taken out from the slots of the respective optical fiber cables have an appropriate length in an appropriate loop shape in the extra length storage case installed in the connection box. Connection.

However, if the optical fiber taken out of the slot is left unconstrained in the axial and circumferential directions of the spacer at the time of the above connection process, the linear expansion of the optical fiber and the entire optical fiber cable occurs. Factors such as a difference in coefficient, a residual elongation strain of an optical fiber, an elongation distortion due to a residual laying tension during construction, and vibration caused a lot of trouble in the optical fiber cable, causing various problems. For example,
By drawing the optical fiber into the optical fiber cable, the extra length of the loop in the extra length storage case decreases,
The problem is that the optical fiber is bent abnormally, resulting in an increase in transmission loss. Another problem is that the optical fiber is strongly rubbed against the spacer when being pulled into the optical fiber cable, and is damaged, or is displaced in the circumferential direction in the slot, and the arrangement is disturbed.

In order to prevent such a problem from occurring, for example, in an optical fiber holding structure disclosed in Japanese Patent Application Laid-Open No. 6-208025, as shown in FIGS. 5 and 6, a tension member 2 and a plurality of The optical fiber cable 1 including the spacer 5 having the slot 4 formed therein, the optical fiber 8 accommodated in the slot 4, and the jacket 9 covering the space around the spacer 5 and the optical fiber 8 is preliminarily removed from the outside. The cover 9 is cut along a predetermined length to expose the spacer 5, and the tip of the spacer 5 is cut to an appropriate length to leave the tension member 2 of a predetermined length exposed.

Then, the exposed tension member 2 of the optical fiber cable 1 is fixed to a fixing portion in a connection box (not shown), and the end of the jacket 9 is held by a holding metal 12 in the connection box. After the fixing, the optical fiber 8 is held and fixed on the outer peripheral surface of the spacer 5 at a position at a predetermined distance from the end of the jacket 9 with respect to the optical fiber 8 in the slot 4. Make the connection. The grip 12
Has a pair of internal fittings 12a arranged so as to sandwich the spacer 5 and a pair of external fittings 12b superimposed on the outside of each gripping fitting 12a, and between the overlapping internal fitting 12a and the external fitting 12b. By sandwiching the jacket 9,
The end of the jacket 9 is fixedly supported. Also,
A protective tape 13 is wound around the outer periphery of the spacer 5 sandwiched between the pair of internal fittings 12a. This protective tape 13
Is for preventing the optical fiber 7 in the slot 4 from being rubbed and damaged by the internal fitting 12a.

By the way, the above-described holding processing of the optical fiber 8 is performed so that the arrangement of the optical fiber 8 on the spacer 5 is not disturbed after the short holding tube 14 is inserted into the optical fiber 8 taken out of the slot 4. The optical fiber 8 is fixed to the outer peripheral surface of the spacer 5 by wrapping the tape 15 while holding the holding tube 14 on the predetermined slot 4. With such an optical fiber holding structure, the optical fiber 8 is fixed to the outer peripheral surface of the spacer 5 by the elastic tightening force of the holding tube 14 and the adhesive fixing force of the tape 15, and is prevented from being drawn into the optical fiber cable. Was.

[0008]

However, in the above-described optical fiber holding structure, after the holding tube 14 is inserted through the optical fiber 8 taken out of the slot 4, the holding tube 14 is not moved from a fixed position on the spacer 5. Since the tape 15 was wound around after positioning by hand, the holding operation itself became difficult when the number of optical fibers 8 was large. Also, the holding tube 14 and the tape 15
However, there was a problem that workability was poor because of the separate structure.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is easy and accurate to arrange and hold an optical fiber taken out of a slot on the outer periphery of a spacer even if the number of optical fibers increases. An object of the present invention is to provide a fiber holding structure capable of improving workability and preventing an increase in transmission loss due to sudden bending or movement of an optical fiber.

[0010]

An optical fiber holding structure according to the present invention for achieving the above object provides an optical fiber taken out of a plurality of slots formed in a spacer for connection processing in a connection box. In the optical fiber holding structure in which the plurality of fiber holding tubes are fixedly arranged on the outer peripheral surface of the spacer, a plurality of fiber holding tubes are integrally arranged in accordance with the arrangement pitch of the slots on the other surface of the tape portion having the adhesive layer formed on one surface. Insert the fiber holding tube of the fiber holding member into the fiber taken out of the slot, align the fiber holding tube on the slot, and move the fiber holding member to the outer periphery of the spacer via the adhesive layer. It is characterized by being wound.

Alternatively, the tape portion may be formed of an elastic member.

According to the above construction, after the optical fiber taken out of the slot of the spacer for connection processing is inserted into each fiber holding tube of the fiber holding member, the fiber holding member is connected to the fiber holding tube via the adhesive layer. By winding the optical fiber around the outer periphery, the optical fiber can be accurately positioned and fixed on the outer periphery of the spacer, and the holding state of the optical fiber to be connected in the connection box can be obtained. Further, if the tape portion is formed of an elastic member, even if there is a slight displacement between the slot and the fiber holding tube, this can be absorbed.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the optical fiber holding structure according to the present invention will be described below in detail with reference to the drawings. The optical fiber cable to which the optical fiber holding structure according to the present invention is applied has the same configuration as that described in the above-described conventional example.
The description is omitted by giving the same numbers as in the conventional example. FIG.
1 shows a fiber holding member used in an embodiment of the optical fiber holding structure according to the present invention.

The fiber holding member 20 has one surface (FIG. 1).
A tape section 21 on which an adhesive layer 25 is formed on
A plurality of fiber holding tubes 23 provided on the other surface of the tape portion 21 having no adhesive layer are integrally formed. Each of the fiber holding tubes 23 on the tape unit 21 faces the adhesive layer 25 of the tape unit 21 toward the spacer 5 of the optical fiber cable 1 so that the tape unit 21
Is wound around the outer periphery of the spacer 5 so that each fiber holding tube 23 on the tape portion 21 is positioned above each slot 4 on the spacer 5 so that the arrangement pitch of the slots 4 on the spacer 5 is Has been deployed accordingly.

The fiber holding tube 23 holds the inserted optical fiber 8 by inserting the optical fiber 8 taken out of the slot 4 of the spacer 5 for connection processing. The above fiber holding member 20
The material and dimensions are set so that the fiber holding tube 23 has an elastic tightening force that requires, for example, a force of 100 g or more for inserting and removing each optical fiber 8 to be inserted. The material of the holding tube 14 is preferably silicone rubber or the like, but other insulating rubber materials or plastic materials can be used as long as conditions such as a coefficient of friction and an elastic coefficient are satisfied. Further, when the fiber holding member 20 is wound around the outer periphery of the spacer 5, the fiber holding member 20 appropriately expands in the circumferential direction due to elasticity. The arrangement pitch of each fiber holding tube 23 is set so as to match the position of the upper slot 4.

In the optical fiber holding structure of the present embodiment, each tension member 2 is preliminarily used for connecting the optical fiber 7.
The optical fiber cable 1 in which the spacer 5 is exposed over a predetermined length fixes the tension member 2 to a fixed portion in a connection box (not shown), and fixes the end position of the jacket 9 to a holding fitting in the connection box. After being held and fixed by the above, an optical fiber holding process is performed using the fiber holding member 20. After that, connection processing between the optical fibers 8 is performed.

As shown in FIG. 2, the fiber holding member 20 sequentially inserts the optical fiber 8 taken out of the slot 4 into the fiber holding tube 23,
The first adhesive layer 25 is wound around the outer periphery of the spacer 5 at a position away from the outer end of the optical fiber cable 1 by a predetermined distance toward the spacer 5 side. At this time, the fiber holding member 20 is aligned so that the fiber holding tube 23 is located on the predetermined slot 4. Then, as shown in FIG. 3, the fiber holding member 20 can hold the optical fiber 8 by attaching the adhesive layer 25 to the outer peripheral surface of the spacer 5 and fixing the same.

According to the above optical fiber holding structure, if the fiber holding member 20 is wound around the outer periphery of the spacer 5 with its adhesive layer 25 side facing the exposed spacer 5 side of the optical fiber cable 1, The fiber holding tubes 23 corresponding to the number of the optical fibers 8 accommodated in the optical fiber cable 1 can be accurately set around the spacer 5.
If the optical fiber 8 taken out of the spacer for connection processing is inserted into each fiber holding tube 23 of the fiber holding member 20 wound around the outer periphery of the spacer 5, the optical fiber to be connected in the connection box is connected. An optical fiber holding state in which 8 is fixed to the outer periphery of the spacer 5 is obtained.

That is, when fixing the optical fiber 8 taken out from the slot 4 of the spacer 5 to the outer periphery of the spacer 5 for the connection processing, the operator must use the respective fiber holding tubes 23 through which the optical fibers 8 are inserted. Need not be positioned around the spacer 5, and even if the number of optical fibers 8 for connection processing increases,
Can be easily and accurately completed.

The cross-sectional shape of the fiber holding tube 23 provided on the fiber holding member 20 is not limited to the rectangular shape shown in the above-described embodiment, but may be changed in design as appropriate, such as circular or elliptical. Further, the fiber holding member 20
The tape portion 21 continuously formed in the longitudinal direction may be cut and used according to the number of fiber holding tubes 23 required for the optical fiber cable 1. In the case of the fiber holding member 20 of the above-described embodiment, the fiber holding tube 2 is disposed in the width direction of the tape portion 21.
3 protrudes, but the fiber holding tube 23
May be matched with the width of the tape portion 21. If the width of the tape portion 21 matches the length of the fiber holding tube 23, a fiber holding member 20 that is long in the tape width direction is manufactured, and then cut into a required tape width. The desired fiber holding member 2
0 may be obtained.

In the above-described embodiment, since a plurality of optical fibers 8 are accommodated in each slot 4 of the spacer 5, the fiber holding tube 23 holds the optical fiber 8 of each slot 4. The dimensions were suitable for However, if there is a case in which a single optical fiber is accommodated, the dimensions, cross-sectional shape, or elastic properties of the fiber holding tube 23 are adjusted so that an appropriate holding force can be obtained even when the single optical fiber 7 is inserted. Is preferably set.

[0022]

According to the optical fiber holding structure of the present invention,
If the fiber holding member is wound around the outer periphery of the spacer with the adhesive layer side facing the exposed spacer side of the optical fiber cable, the fiber according to the number of optical fiber bundles accommodated in the optical fiber cable The holding tube can be set accurately around the spacer. If the optical fiber taken out of the spacer for connection processing is inserted into each fiber holding tube of the fiber holding member wound around the outer circumference of the spacer, the optical fiber to be connected in the connection box is connected to the outer circumference of the spacer. An optical fiber holding state fixed above is obtained. That is, when fixing the optical fiber taken out of the slot for the connection process on the outer periphery of the spacer, it is not necessary for the operator to position each fiber holding tube through which each optical fiber has been inserted around the spacer. Even when the number of optical fibers accommodated in the fiber cable increases, the operation of fixing the optical fiber around the spacer can be completed easily and accurately. Therefore, with the optical fiber holding structure, it is possible to prevent an increase in transmission loss due to factors such as a difference in linear expansion coefficient of the optical fiber cable and vibration of the optical fiber with a simple operation.

[Brief description of the drawings]

FIG. 1 is a perspective view of a fiber holding member used in an embodiment of an optical fiber holding structure according to the present invention.

FIG. 2 is a perspective view showing a state in which the fiber holding member shown in FIG. 1 is mounted on a spacer from which the jacket of the optical fiber cable is stripped.

FIG. 3 is a perspective view of one embodiment of an optical fiber holding structure according to the present invention.

FIG. 4 is a sectional view taken along line BB in FIG. 4;

FIG. 5 is a perspective view of a conventional optical fiber holding structure.

FIG. 6 is a sectional view taken along the line AA in FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical fiber cable 2 Tension member 4 Slot 5 Spacer 8 Optical fiber 9 Jacket 20 Fiber holding member 21 Tape part 23 Fiber holding tube 25 Adhesive layer

Claims (2)

[Claims] 1. An optical fiber holding structure in which optical fibers taken out from a plurality of slots formed in a spacer are fixedly arranged on an outer peripheral surface of the spacer for connection processing in a connection box. On the other surface of the formed tape portion, insert the fiber holding tube of the fiber holding member, in which a plurality of fiber holding tubes are integrally arranged in accordance with the arrangement pitch of the slots, into the fiber taken out of the slot, An optical fiber holding structure, wherein the fiber holding tube is positioned on the slot, and the fiber holding member is wound around the outer periphery of the spacer via the adhesive layer. 2. The optical fiber holding structure according to claim 1, wherein said tape portion is formed of an elastic member.