JPH1164698A - Production of optical fiber cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the housing of many ribbon-like coated optical fibers without increasing the number of a supply stand for supplying the ribbon-like coated optical fibers. SOLUTION: This process consists in producing the optical fiber cable by providing the circumference of a tension member 1 with a plastic housing body, providing the surface of the plastic housing body with grooves and laminating and housing the ribbon-like coated optical fibers in these grooves. At this time, the deep grooves 3 and the shallow grooves 3 are formed by changing the depth of the grooves of the plastic housing body 2. The stage for housing the ribbon-like coated optical fibers 5 is divided twice. The ribbon-like coated optical fibers 5 are first housed in the deep grooves 3 and the ribbon-like coated optical fibers 5 are housed in the shallow grooves 4 in the next stage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an optical fiber cable in which a tape-shaped optical fiber is laminated and housed in a plastic housing having a groove.

[0002]

2. Description of the Related Art An optical fiber cable in which a plastic housing having a groove around a tensile strength member and a tape-shaped optical fiber core is laminated and housed in the groove is used as a typical example of a multi-core optical fiber cable. in use.

FIG. 3A is a cross-sectional view of one example. 3
1 is a tensile strength member made of steel wire, steel stranded wire, FRP, etc., 32
Is a plastic container, 32a is a groove provided in the plastic container, 33 is an optical fiber ribbon, 34 is an upper winding tape, and 35 is a coating made of plastic or the like.
In FIG. 3A, the number of the grooves 32a is 6, but the required number of grooves is provided, and the number of grooves may be as many as 10 or more.

The optical fiber ribbon 33 laminated in the groove 32a has a cross section shown in FIG. 3B, and is coated with an ultraviolet curable resin or the like.
a are arranged in parallel, and are collectively coated 33b with an ultraviolet curable resin or the like. It should be noted that a plurality of such tape-shaped optical fiber core wires 33 are stacked and accommodated in the groove 32a. In FIG. 3A, a tape-shaped optical fiber core wire 3 is shown.
3 are stacked five by five, but in many cases, ten or more may be stacked. Also, in FIG. 3B, the number of optical fiber core wires 33a is eight, but there are also four optical fiber cores or other optical fibers.

In the manufacture of the above-described optical fiber cable, a large number of tape-type optical fiber cores are simultaneously accommodated in a large number of grooves, so that a large number of supply stands for installing reels for supplying the tape-type optical fiber cores are provided. There is a need. However, manufacturing facilities are limited and the number of supply stands is limited. At present, the maximum number of supply stands is about 125. Using such a facility, 5 to 10 pieces of 8-core optical fiber cores are stacked and stored in 13 grooves, respectively. Fiber optic cables are being manufactured.

In the case where further multi-core is required, a unit in which a tape-shaped optical fiber core wire is housed in a groove of a plastic housing and wound up is used as a unit. A multi-core optical fiber cable is manufactured by a method of twisting around the support wire of the present invention. But,
Such an optical fiber cable using a plurality of units has a problem that work such as taking out a tape-like optical fiber core becomes complicated or that the entire outer diameter of the cable becomes large relative to the number of optical fiber cores. .

In order to store a large number of optical fibers in the groove of the plastic container, a method of storing the optical fibers in a plurality of times instead of at once is also conceivable. For example, in the case of an optical fiber cable that accommodates 16 tape-shaped optical fiber cores per groove, eight optical fibers are stored in the first storing step, and the above eight optical fibers are further stored in the second storing step. This is a method of storing eight sheets. In this case, the number of supply stands may be set to be equal to eight, so that a multi-core optical fiber cable can be manufactured without increasing the number of supply stands.

In this method, however, the first storage is performed by holding down the plastic storage body during the first storage so that the eight sheets stored earlier do not jump out of the groove during the next storage operation. At the time of storage, it is necessary to store the tape-shaped optical fiber while removing the presser winding. Even in this case, there is a danger that the eight previously stored tape-shaped optical fiber cores may protrude from the loose groove between the position where the presser winding is removed and the location where the tape-shaped optical fiber core is stored.

It is also conceivable that the tape is wound directly on the eight tape-shaped optical fiber cores stored in the first time with the same tape as the tape-shaped optical fiber core. If the tension is not significantly increased, the holding tape may jump out of the groove together with the optical fiber ribbon. Further, if the tension of the presser winding is too large, there is a problem that the transmission characteristics of the inner tape-shaped optical fiber core are deteriorated.

[0010]

As described in detail above, in the prior art, when an optical fiber cable having a unit configuration using a plurality of grooved spacers is used, the outer diameter of the cable is less than the number of optical fiber cores. There is a problem of increasing. In addition, if an attempt is made to increase the number of tape-like optical fiber cores required for an optical fiber cable using one grooved spacer, it is necessary to increase the number of supply stands where tape-type optical fiber core supply reels are installed. However, there is a problem that the equipment cost increases. In addition, the method of storing the tape-shaped optical fiber in the groove twice has a risk that the previously stored tape-shaped optical fiber is likely to jump out of the groove. The present invention provides a method for manufacturing an optical fiber cable that avoids such problems of the related art.

[0011]

In the method of manufacturing an optical fiber cable according to the present invention, the depth of the groove of the grooved spacer is changed into a deep groove and a shallow groove. The core wire is housed, and the tape-shaped optical fiber core wire is housed in the shallow groove in the next second step.

[0012]

FIG. 1 is a sectional view showing an example of an optical fiber cable according to the manufacturing method of the present invention, wherein 1 is a support wire made of a steel wire, a steel stranded wire, FRP or the like, and 2 is a plastic wire. 3 is a deep groove provided in the plastic container, and 4 is a shallow groove provided in the plastic container.
Further, 5 is a tape-shaped optical fiber core wire in which grooves are stacked and housed, 6 is a holding insertion groove, 7 is a holding coarse winding, 8 is an upper winding, and 9 is a coating made of plastic or the like.

FIGS. 2A and 2B are development views of examples of grooves formed on the surface of the plastic housing of the optical fiber cable according to the present invention, wherein 2 is a housing made of plastic, 3 is a deep groove, Reference numeral 4 denotes a shallow groove, and 6 denotes a holding insertion groove. In the example of FIG. 2A, the deep groove 3 and the shallow groove 4 are provided around the plastic housing 2 in the same pitch at the same pitch and spirally in the same direction. The holding groove 6 is provided spirally in the opposite direction so as to intersect with the deep groove 3 and the shallow groove 4.

In the example shown in FIG. 2B, the deep groove 3 and the shallow groove 4 are provided so as to intersect with each other, and the holding insertion groove 6 is provided in parallel with the shallow groove 4. In addition to FIGS. 2A and 2B,
A method is also conceivable in which the pitch of the deep groove and that of the shallow groove intersect with each other by changing the pitch while keeping the spiral direction the same.

Each of the deep groove 3, the shallow groove 4, and the holding insert groove 6 is formed in a cross section of the following size. The width of the deep groove 3 and the shallow groove 4 is set to be slightly larger than the width of the tape-shaped optical fiber core to be stored. In addition, the depth of the shallow groove 4 is designed to be larger than that in consideration of the height of the lamination of the tape-shaped optical fibers to be stored in the second groove in the shallow groove 4. In addition, deep groove 3
Is designed to be greater than or equal to the sum of the height of the stack of tape-shaped optical fibers stored in the first storing step and the depth of the shallow groove 4.

The width of the holding insertion groove is set to a width in which the coarse holding roll can be inserted, and the depth is equal to or greater than the depth of the shallow groove 4. Design below the one with the stack height subtracted. When the shallow groove 4 and the deep groove 3 intersect with each other, one of the shallow grooves 4 can be used as the holding insertion groove without forming the holding insertion groove exclusively.

Next, a process for accommodating the tape-shaped optical fiber core in the plastic container having the above-described deep groove, shallow groove, and holding insertion groove will be described. First, in the first step, a tape-shaped optical fiber core is laminated and stored in the deep groove 3,
A tape or a cord is roughly wrapped around the holding insertion groove so as to hold the tape-shaped optical fiber so as not to protrude from the groove. Since the depth of the deep groove 3 is designed to be greater than the sum of the depth of the shallow groove 4 and the height of the lamination of the tape-shaped optical fibers stored in the first storing step, the depth of the deep groove 3 is increased. The top surface of the optical fiber ribbon is below the bottom of the shallow groove. In addition, the depth of the holding insertion groove is designed to be not less than the depth of the shallow groove 4 and not more than the depth of the deep groove 3 minus the stacking height of the tape-shaped optical fiber core wires accommodated in the deep groove 3.
The holding coarse winding is above the upper surface of the tape-shaped optical fiber core laminated in the deep groove and below the depth of the shallow groove 4.

Next, in a second step, a tape-shaped optical fiber core is laminated and stored in the shallow groove 4. In this case, since the tape-shaped optical fiber core wire and the holding coarse winding stored in the first step are deeper than the depth of the shallow groove, the lamination of the tape-shaped optical fiber core wire in the second step, It does not hinder storage. In addition, plastic tape, fiber such as nylon or cotton, or the like can be used as the coarse presser wound in the presser insertion groove. The use of a water-absorbing material is also effective in increasing the waterproofness of the optical fiber cable.

[0019]

As described above, in the present invention, the process of storing the tape-shaped optical fiber core into the grooved spacer is divided into two steps. It is possible to manufacture an optical fiber cable containing a large number of tape-shaped optical fiber cores without increasing the number of supply stands that supply the tape-shaped optical fiber cores.

For example, in a case where eight tape-shaped optical fiber cores are stored using 125 supply stands,
A total of 125 tape-shaped optical fibers are stored in the deep groove,
If a total of 125 tape-shaped optical fiber cores are accommodated in the shallow groove, an optical fiber cable having 250 tape-shaped optical fiber cores, that is, a 2,000 multi-core optical fiber cable can be used without increasing the number of supply stands. It is possible to manufacture. Further, since it is not necessary to use a plurality of grooved spacers, there is no problem that the outer diameter of the cable becomes large in proportion to the number of optical fibers.

[Brief description of the drawings]

FIG. 1 is a sectional view of an optical fiber cable according to a manufacturing method of the present invention.

FIGS. 2A and 2B are developed views showing examples of grooves formed on the surface of a plastic container according to the present invention.

3A is a cross-sectional view of a conventional optical fiber cable, and FIG. 3B is a cross-sectional view of a tape-shaped optical fiber core.

[Explanation of symbols]

 1: Support wire 2: Plastic container 3: Deep groove 4: Shallow groove 5: Tape-shaped optical fiber core wire 6: Holding insertion groove 7: Holding coarse winding 8: Top winding 9: Coating

Claims (4)

[Claims] 1. A method for manufacturing an optical fiber cable comprising: providing a plastic container having a groove around a strength member and laminating and storing a tape-shaped optical fiber core wire in the groove; A deep groove and a shallow groove are provided by changing the depth of the tape-shaped optical fiber core wire in the deep groove, and a second step of storing the tape-shaped optical fiber core wire in the shallow groove. Manufacturing method of an optical fiber cable. 2. The plastic container has, besides the deep groove and the shallow groove, a pressing insertion groove intersecting with the deep groove. In the first step, the tape-shaped optical fiber core is stored in the deep groove, and the pressing insertion groove is roughened. The method for manufacturing an optical fiber cable according to claim 1, wherein the optical fiber cable is wound. 3. A plastic container in which a deep groove and a shallow groove are provided with a helical pitch or a helical direction so as to intersect spirally, and a tape-shaped optical fiber core is stored in the deep groove in the first step. 2. The method for manufacturing an optical fiber cable according to claim 1, wherein a rough press winding is performed on one of the shallow grooves. 4. The depth of the deep groove of the plastic container is equal to or greater than the sum of the lamination height of the tape-shaped optical fiber core wires to be stored and laminated in the first step and the depth of the shallow groove. The method for manufacturing an optical fiber cable according to claim 1.