JP2005062360A - Slot type optical fiber cable and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a slot type optical fiber cable and a manufacturing method therefor which permit to reduce cost and man-hours by eliminating a wrapping tape. <P>SOLUTION: The slot type optical fiber cable 40 holds coated secondary optical fiber tapes 14 in a plurality of slots 21 provided in the outer periphery of the slots 10. The outer peripheral part of each slot rib 22 between adjacent slots 21 is provided with an extension part which projects outward and also extends along the longitudinal direction of the slots 21, and is directly provided with a sheath 13 on the outer periphery of the slot 10 with the extension parts 40 bent to cover the upper openings of the adjacent slots 21. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a slot type optical fiber cable and a manufacturing method thereof.

Conventionally, various types of optical fiber cables have been proposed (see, for example, Patent Document 1).
For example, as shown in FIG. 8, a slot-type optical fiber cable 110 has a tension member 101 at the center, and a slot 100 in which a resin-made slot rod 102 is integrally provided around the tension member 101. doing.

For example, a plurality of slot grooves 103 are spirally twisted on the outer peripheral surface of the slot rod 102, and a laminated body 105 in which tape core wires (optical fibers) 104 are laminated in each slot groove 103. Contained.
Further, a presser winding tape (upper winding tape) 106 is wound around the outer peripheral surface of the slot rod 102, and a sheath 107 is provided outside the presser winding tape 106 so that the slot-type optical fiber cable 110 is connected. It is composed.

JP 2001-31860 A

By the way, the sheath 107 in the conventional slot type optical fiber cable 110 as described above is formed by extruding a thermoplastic resin such as polyethylene, and this resin is in a molten state at a high temperature at the time of extrusion molding. .
Therefore, when the tape core 104 comes into contact with such a high-temperature resin, the jacket of the tape core 104 may be affected by heat, or the optical fiber constituting the tape core 104 may be adversely affected. . If the tape core wire 104 jumps out of the slot groove 103 before forming the sheath 107, a normal slot type optical fiber cable 110 cannot be formed.

  Therefore, after the tape core wire 104 is accommodated in the slot groove 103, the press core tape 106 such as propylene or polyethylene is wound to prevent the tape core wire 104 from jumping out of the slot groove 103, or in a later step the sheath 107. The tape core wire 104 is protected from the high-temperature resin when the wire is provided.

  For this reason, there is a problem that the presser winding tape 106 causes an increase in the number of parts and man-hours and causes an increase in cost.

  An object of the present invention is made by paying attention to the conventional problems as described above, and a slot-type optical fiber cable that can reduce the cost and man-hours by omitting the presser winding tape, and its It is to provide a manufacturing method.

  The above object of the present invention is a slot-type optical fiber cable in which an optical fiber is accommodated in a plurality of slot grooves provided on the outer periphery of a slot, and is provided at the outer peripheral portion of each slot rib between adjacent slot grooves. Has an extension portion extending outwardly and extending along the longitudinal direction of the slot groove, and the extension portion is bent so as to cover the upper opening of the adjacent slot groove. This is achieved by a slot type optical fiber cable characterized in that a sheath is provided on the outer periphery.

  Another object of the present invention is a method of manufacturing a slot-type optical fiber cable in which an optical fiber is accommodated in a plurality of slot grooves provided on the outer periphery of a slot, and each of the slots between adjacent slot grooves is provided. An extension portion that protrudes outward and extends along the longitudinal direction of the slot groove extends on the outer periphery of the slot rib, and after the optical fiber is received in the slot groove, an upper opening of the adjacent slot groove is provided. This is achieved by a method of manufacturing a slot-type optical fiber cable, wherein a sheath is provided on the outer periphery of the slot in a state where the extension portion is bent so as to cover the cable.

  Preferably, a sheath is provided on the outer periphery of the slot in a state where the extension portion is bent by the fixing means so as to cover the upper opening of the adjacent slot groove.

  Preferably, a sheath is provided on the outer periphery of the slot in a state where the extension portion is bent so as to cover the upper opening of the adjacent slot groove by a guide member having a narrowed through hole.

  Preferably, after the base end portion of the extension portion is thermoformed in a bent state, a sheath is provided on the outer periphery of the slot.

  According to the slot-type optical fiber cable of the present invention, the extension provided on the outer periphery of each slot rib is bent so as to cover the upper opening of the adjacent slot groove, so that the slot groove in which the optical fiber is accommodated. The optical fiber can be prevented from jumping out of the slot groove.

  Further, since the extension portion closes the opening of the slot groove, the optical fiber does not directly contact the sheath. For this reason, the optical fiber can be protected from high-temperature resin when the sheath is integrally formed on the outer periphery of the slot.

  Therefore, after the optical fiber is accommodated in the slot groove, the extension portion provided in the slot covers the opening of the slot groove, so that it is possible to omit the press-wound tape that has been conventionally required, and to reduce the cost.

Hereinafter, a slot-type optical fiber cable and a manufacturing method thereof according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a cross-sectional view of a slot-type optical fiber cable according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of a slot used in the slot-type optical fiber cable shown in FIG.

  As shown in FIG. 1, the slot-type optical fiber cable 30 of the present embodiment includes, for example, a slot that accommodates in a slot groove 21 a laminated body 15 in which a plurality of optical fibers 14 in which a plurality of optical fibers are integrated into a tape shape. 10 and a sheath 12 provided on the outer periphery of the slot 10.

  As shown in FIG. 2, the slot 10 has a tension member 11 in the center, and a resin-made slot rod 20 is integrally provided around the tension member 11 by extrusion molding. A plurality of (in this embodiment, five) parallel slot grooves 21 for accommodating the laminate 15 are provided along the longitudinal direction on the outer peripheral surface of the slot rod 20.

Slot ribs 22 are formed between the adjacent slot grooves 21 and 21, and the outer periphery of each slot rib 22 extends outward and extends along the longitudinal direction of the slot groove 21. A portion 40 is extended. Each extension portion 40 is a thin plate-like rib (for example, a thickness of about 0.1 mm to 0.2 mm) integrally provided by extending the side wall 21a of one adjacent slot groove 21 outward. .
The extension portions 40 can be formed by extrusion molding simultaneously with the slot grooves 21 and the like when the slot rod 20 is integrally formed by extrusion molding around the tension member 11, for example.

Furthermore, as shown in FIG. 3, it is desirable that the length L of the extended portion 40 be larger than the upper opening width W of the slot groove 21.
Thus, when the extension portion 40 is bent from the base end portion to cover the upper opening of the slot groove 21, the tip of the extension portion 40 can cross the slot groove 21 and reach the adjacent slot rib 22 (in FIG. 3). , Indicated by a two-dot chain line).
For this reason, the extended portion 40 can cover the upper opening of the slot groove 21 without falling into the slot groove 21.

Next, a manufacturing method of the slot type optical fiber cable 30 of the present invention using the slot 10 will be described.
First, the slot 10 having the extended portion 40 as shown in FIG. 2 is manufactured.
Next, as shown in FIGS. 4 and 5, after the laminated body 15 of the tape core wire 14 is accommodated (assembled) in each slot groove 21 of the slot 10, the extended portion 30 is bent to open the opening 23 b of the slot groove 23. Cover.

At this time, the extended portion 40 is bent so as to cover the upper opening of the adjacent slot groove 21 by, for example, a winding string 12 as a fixing means wound spirally around the slot 10.
That is, by winding such a winding string 12 around the slot 10 in a spiral manner, the tape core wire 14 is accommodated in each slot groove 21 and extended so as to cover the upper opening of the adjacent slot groove 21. Since the portion 40 can be continuously bent, the bending operation of the extended portion 40 is facilitated.

Thereafter, a sheath 13 is provided by extrusion from above the winding string 12 wound around the outer periphery of the slot 10 to form a slot type optical fiber cable 30 as shown in FIG.
At this time, since the winding string 12 is wound around the slot 10, the bent extended portion 40 is held in a bent state, so that it does not inadvertently return to the original shape. The sheath 13 can be easily formed on the outer periphery.

That is, according to the slot type optical fiber cable 30 according to the present embodiment, the opening of the slot groove 21 in which the tape core wire 14 is accommodated is covered by the extension portion 40, so that the tape core wire 14 jumps out of the slot groove 21. Can be prevented.
Further, since the extended portion 40 closes the opening of the slot groove 21, the tape core wire 14 does not directly contact the sheath 13. For this reason, the tape core wire 14 can be protected from high-temperature resin when the sheath 13 is integrally formed on the outer periphery of the slot 10.

  Therefore, after the tape core wire 14 is accommodated in the slot groove 23, the extension portion 40 provided in the slot 10 covers the opening of the slot groove 21, so that the presser winding tape that has been conventionally required can be omitted, and the cost can be reduced. Can be achieved.

  The winding string 12 is wound around the outer periphery of the slot 10 in order to bend the extended portion 40 continuously, and does not need to be wound more tightly than necessary along the longitudinal direction of the slot 10. Compared to the presser winding tape that must be tightly wound to cover the opening of the slot groove 21, it is cheaper and the winding operation is also easier.

  Further, in the slot type optical fiber cable 30 according to the present embodiment, the extension portion 40 provided on the outer peripheral portion of each slot rib 22 is bent so as to cover the upper opening of the adjacent slot groove 21. Since the contact area with the sheath 13 formed on the outer peripheral surface of the first and second outer surfaces is substantially widened, it is possible to increase the frictional force and prevent relative movement of each other.

  Therefore, even when there is a difference between the contraction force in the longitudinal direction of the sheath 13 and the contraction force of the slot 10 over time, the slot 10 can be prevented from being exposed at the cable end. It is also possible to prevent deterioration of the tape core 14 accommodated in the cable and increase in transmission loss of the slot type optical fiber cable 30 due to getting wet.

The slot type optical fiber cable and the manufacturing method thereof according to the present invention are not limited to the above-described embodiments, and various modifications and improvements can be made based on the gist of the present invention.
For example, in the above-described embodiment, as shown in FIG. 4, after the tape core wire 14 is accommodated in each slot groove 21, the winding cord 12 that is a fixing means is spirally wound around the slot 10. The case where the slot-type optical fiber cable 30 is manufactured by extruding the sheath 13 while continuously bending the extension portion 40 so as to cover the upper opening of the adjacent slot groove 21 has been described. It is not limited.

  For example, as shown in FIG. 6, by inserting the slot 10 containing the tape core wire 14 in each slot groove 21 into the narrowed through hole of the guide member 12, the sheath 13 is simultaneously bent while bending the extension portion 40. The slot-type optical fiber cable 10 can be manufactured by extrusion molding.

Alternatively, after the tape core wire 14 is accommodated in each slot groove 21, the base end portion of the extension portion 40 is heat-formed in a bent state, and then the sheath 13 can be extruded and formed on the outer periphery of the slot 10.
In such a case, it is possible to omit the tape winding, which has been conventionally required, and since the winding string 12 is not required, the number of parts and man-hours can be further reduced to reduce the cost.

Further, in the above-described embodiment, the thin plate-like shape as shown in FIG. 3 has been described as the shape of the extension portion 40. For example, the shapes as shown in FIGS. .
In the extended portion 40A shown in FIG. 7A, a notch 41a is provided on the slot groove 21 side of the base end portion, and can be easily bent when the extended portion 40A is bent from the base end portion.

Further, the distal end portion of the bent extended portion 40A is placed on the step portion of the notch 41b provided at the upper end corner portion of the adjacent slot rib 22, and the corner portion at the base end portion of the bent extended portion 40A is the notched portion. 41a (shown by a two-dot chain line in FIG. 7A).
Therefore, the step difference from the outer peripheral surface of the slot rib 22 that occurs when the extended portion 40A covers the slot groove 21 can be reduced.

In the extended portion 40B shown in FIG. 7B, a thin hinge portion 42a is provided at the base end portion of the flat plate-like extended portion 40B to facilitate bending. At this time, a notch 42b is also provided at the upper corner of the adjacent slot rib 22 with which the tip of the extended portion 40A abuts.
Further, since the thin hinge portion 42a is provided at the base end portion, the extended portion 40B is bent at a substantially right angle at the base end portion, and the step generated at the bent portion can be reduced.

In the extended portion 40C shown in FIG. 7C, a taper 43a is provided so that the plate thickness of the extended portion 40C becomes thinner toward the tip.
Therefore, the step generated when the distal end portion of the bent extended portion 40A comes into contact with the outer peripheral surface of the adjacent slot rib 22 can be reduced.

In the extension portion 40D shown in FIG. 7D, a step 44 is provided at the tip of the flat extension portion 40D so that the plate thickness is reduced.
Therefore, the step generated when the tip end portion of the bent extended portion 40D comes into contact with the outer peripheral surface of the adjacent slot rib 22 can be reduced.

In addition, the material, shape, dimensions, form, number, location, etc. of the slot-type optical fiber cable 30, the slot 10, the sheath 13, etc. exemplified in the above-described embodiment are arbitrary as long as the present invention can be achieved, It is not limited.
For example, in the slot type optical fiber cable 30 exemplified in the above embodiment, the slot 10 having a plurality of parallel slot grooves 21 provided on the outer peripheral surface is used. However, the slot type optical fiber cable 30 has a plurality of slot grooves twisted in one direction. A slot or a slot having a slot groove twisted while repeating forward and reverse in the longitudinal direction (so-called SZ tape slot) can also be used.

It is sectional drawing of the slot type optical fiber cable which concerns on one Embodiment of this invention. It is sectional drawing of the slot used for the slot type optical fiber cable shown in FIG. FIG. 2 is an enlarged sectional view of a main part of the slot shown in FIG. 1. It is a fragmentary perspective view for demonstrating the manufacturing method of the slot type optical fiber cable shown in FIG. It is sectional drawing for demonstrating the manufacturing method of the slot type optical fiber cable shown in FIG. FIG. 8 is a partial perspective view for explaining another manufacturing method of the slot type optical fiber cable shown in FIG. 1. (A)-(d) is sectional drawing which shows the modification of the extension part shown in FIG. It is sectional drawing of the slot type optical fiber cable known conventionally.

Explanation of symbols

10 Slot 12 Winding string 13 Sheath 14 Tape core (optical fiber)
20 slot rod 21 slot groove 22 slot rib 30 slot type optical fiber cable 40 extended portion

Claims (5)

A slot-type optical fiber cable in which an optical fiber is accommodated in a plurality of slot grooves provided on the outer periphery of the slot,
On the outer peripheral portion of each slot rib between the adjacent slot grooves, an extending portion that extends outward and extends along the longitudinal direction of the slot groove is extended,
A slot type optical fiber cable, wherein a sheath is provided on an outer periphery of the slot in a state where the extension portion is bent so as to cover an upper opening of an adjacent slot groove. A method of manufacturing a slot-type optical fiber cable in which an optical fiber is accommodated in a plurality of slot grooves provided on the outer periphery of a slot,
On the outer peripheral portion of each slot rib between the adjacent slot grooves, an extending portion that extends outward and extends along the longitudinal direction of the slot groove is extended,
A slot-type optical fiber cable, wherein after the optical fiber is accommodated in the slot groove, a sheath is provided on the outer periphery of the slot in a state where the extension portion is bent so as to cover the upper opening of the adjacent slot groove. Production method.   The slot-type optical fiber cable according to claim 2, wherein a sheath is provided on an outer periphery of the slot in a state where the extension portion is bent so as to cover an upper opening of an adjacent slot groove by a fixing means. Manufacturing method.   The sheath is provided on the outer periphery of the slot in a state where the extended portion is bent so as to cover an upper opening of an adjacent slot groove by a guide member having a narrowed through hole. Of manufacturing a slotted optical fiber cable. 3. The method of manufacturing a slot-type optical fiber cable according to claim 2, wherein a sheath is provided on an outer periphery of the slot after the base end portion of the extension portion is thermoformed in a bent state.

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