JPS63198009A - Optical cable and its production - Google Patents

Abstract

PURPOSE:To prevent jumping-out of optical fibers from a grooved spacer and to increase the speed of producing an optical cable by forming the cable in a manner as to have the structure in which the plural optical fibers are roughly wound by integrally restraining. CONSTITUTION:The optical fibers 3 are housed in the grooves of the grooved spacer 2 in the stage of integrally restraining plural pieces thereof by the color- coded rough windings 4. The production of the cable is executed by supplying the grooved spacer having the spiral grooves inverted periodically in the directions on the outside circumference from a grooved spacer supplying device 6. On the other hand, the plural optical fibers supplied from an optical fiber supplying device 7 are aggregated under twisting by an optical fiber inverting device 12 and are roughly wound by a rough winding device 13, by which an optical fiber group is formed. After the optical fibers are integrally restrained, the fibers are let off by an optical fiber let-off device 8 and are housed into the grooves of the grooved spacer by an optical fiber housing device 9. The fibers are then applied with a top winding tape 10 and is taken up on a take-up machine 11.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an original cable having a structure in which a plurality of optical fibers are housed in the spiral grooves of a grooved spacer having a spiral groove whose direction is periodically reversed on the outer periphery. The present invention relates to a manufacturing method thereof.

[Conventional technology]

FIG. 5 shows a conventional grooved spacer 2 of this type having an inverted open spiral groove on its outer periphery, with a plurality of optical fibers 3 in the spiral groove.
FIG. 2 is a cross-sectional view of a spiral grooved spacer type optical cable that houses the optical cable and has a sheath 5 on its outer periphery. 1 indicates a tensile strength member. A conventional spiral grooved spacer type optical fiber has a structure in which a plurality of optical fibers 3 are randomly housed in a groove.

FIG. 6 is a diagram illustrating a conventional method for manufacturing a direction-reversing spiral grooved spacer type optical cable. A grooved spacer having a spiral groove whose direction is periodically reversed is supplied from the grooved spacer supply device 6 on the outer periphery, and a plurality of optical fibers are supplied from the destination fiber supply device 7 to the original fiber feeding device 8. A plurality of optical fibers are then delivered to an optical fiber storage device 9 that performs a reversal operation in accordance with the reversal position of the groove for storing the optical fibers in the groove of the grooved spacer. Optical fiber storage device 9
This is a device that functions to introduce the original fiber into the groove, and is usually referred to as a reversal batten. After the original fiber is stored in the groove of the grooved spacer by the original fiber storage device 9, the upper tape 10 is applied to the outer periphery to form the original cable, and the winding machine 1
Wind it up to 1.

[Problem that the invention seeks to solve]

The traditional structure of an optical cable is that a plurality of original fibers are housed in one groove, and each of the original fibers is housed in such a way that it can move independently within the groove. ing. For this reason, when manufacturing the original cable, in the process of storing the optical fiber in the groove of the grooved spacer,
There is the following problem.

In other words, if the length of the stored optical fiber is different from the unit length of the groove, and some original fibers are stored in the groove and are loaded with excessive extra length or tension due to their position at the time of death. However, adding a micropend to the optical fiber increases optical transmission loss.

ii When storing multiple optical fibers, the optical fibers may jump out of the spiral groove, especially at the point where the direction of the groove is reversed. The fiber may be pinched and broken.

[Means for solving problems]

In order to solve the conventional problems, the present invention provides an optical cable having a structure in which a plurality of optical fibers are housed in a spiral groove of a grooved spacer having a spiral groove whose direction is periodically reversed on the outer periphery. is characterized in that it has a structure in which coarse winding is applied to collectively restrain the optical fibers, and in particular, the coarse winding is characterized by color-coding for each group of collectively restrained optical fibers. Further, the optical cable manufacturing method of the present invention includes a step of forming an optical fiber group by roughly winding a plurality of optical fibers to collectively restrain them while periodically reversing the direction. The present invention is characterized in that it includes a step of synchronizing the direction reversal period of the optical fiber with the direction reversal period of the spiral groove of the grooved spacer, and aligning the direction of both reversals in opposite directions.

[For production]

In the optical cable of the present invention, a plurality of optical fibers are loosely wound to form one optical fiber group and stored in the groove of the grooved spacer. To prevent the fibers from jumping out, to keep the difference in length of multiple optical fibers stored in the spiral groove to less than a certain length, and to color-code the coarse windings for each optical fiber group. Allows for identification.

The optical cable manufacturing method of the present invention collects optical fibers,
By aligning the optical fibers while reversing their directions before rough winding, the lengths of each optical fiber can be made uniform, and the reversal period of the helical grooves of the optical fiber and the grooved spacer can be adjusted respectively. By synchronizing the optical fibers and making the reversal direction opposite, an extra length can be provided by twisting the optical fibers. Examples will be described below based on the drawings.

〔Example〕

FIGS. 1a and 1b show an outline of the structure of the optical cable of the present invention.

Figure 1a shows the cross-sectional structure of an optical cable, where 1 is a tensile strength member, 2
3 is a grooved spacer having a spiral groove whose direction is periodically reversed on its outer periphery; 3 is an optical fiber; 4 is loosely wound; in this example, a plurality of optical fibers are restrained at once by color-coded coarsely wound with colored thread or tape; It is housed in the groove of the grooved spacer 2. 5
indicates a sheath. FIG. 1 shows a state in which a plurality of optical fibers 3 are provided with color-coded coarse windings 4 for collectively restraining them.

FIG. 2 is a diagram illustrating the method for manufacturing an optical cable of the present invention. A grooved spacer supply device 6 supplies a grooved spacer having a spiral groove on its outer periphery whose direction is periodically reversed. On the other hand, the plurality of optical fibers supplied from the optical fiber supply device 7 are rotated by the optical fiber reversing device 12 with the same reversing period as the reversing period in the groove direction of the grooved spacer, and with the reversing direction being the same as the reversing period of the groove direction. The optical fibers are assembled while being twisted in a direction opposite to the period, and coarsely wound by a coarse winding device 13 to form an optical fiber group. After being collectively restrained by the optical fiber group, the optical fiber feeding device [8] guides the optical fiber group according to the position of the spiral groove of the grooved spacer and introduces it into the groove. It is stored in the groove of the grooved spacer. Thereafter, an upper tape 10 is applied to the outer periphery to form an optical cable, which is then wound on a winder 11.

As shown in FIG. 3, the optical fiber 3 is
Before collecting six A6 fibers and roughly winding them, by reversing the directions of the optical fibers 3 as shown by the arrows and aligning them, each of the optical fibers 3 can be rolled.
A6 can be placed evenly in the top, bottom, left, and right positions, and the optical fibers are aligned by an optical fiber reversing device that forms a reversal plate, and the length of each optical fiber is adjusted. are uniformly aligned.

Further, by inverting and assembling the optical fibers, extra length is given to the optical fibers by twisting. By synchronizing the reversal period in the groove direction of the grooved spacer and the reversal period for reversing and assembling the optical fibers, and by making the reversal directions of the two opposite to each other, the optical fiber can be twisted approximately twice as much. can be given length. Here, the extra length of the optical fiber due to twisting is shown in the explanatory diagram of FIG. 4 as follows.

That is, in Fig. 4, d is the diameter of the optical fiber, D is the core diameter of the optical fiber assembly, P is the final gathering pitch in the same direction, and n is the circumference of the optical fiber in the same direction. If the number of rotations is 2n (e
-P), and extra length is given to the optical fiber by this twisting.

〔Effect of the invention〕

As described above, the optical cable and method for manufacturing the same according to the present invention provide the following effects.

i Since it is possible to prevent the optical fiber from popping out from the grooved spacer, the manufacturing speed of optical cables is improved and it is effective in reducing the cost of optical cables.

ii. Optical fiber groups can be identified by coloring the loosely wrapped material, such as thread or tape, applied to form the optical fiber groups.

iii. Since the lengths of the optical fibers assembled in one group of optical fibers can be made equal, it is possible to prevent an increase in optical transmission loss of the optical fibers that may occur during manufacturing.

The 1v optical fiber is roughly wound and assembled without reversing its direction.
Since the optical fibers are housed in the grooves of the grooved spacer as a group, there is an extra length in the optical fiber iper length compared to the length of the grooved spacer. Therefore, even if tension is applied to the optical cable, excessive tension is not applied to the optical fiber, and a stable optical cable can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a structural diagram of the optical cable of the present invention, Fig. 2 is an explanatory diagram of the optical cable manufacturing method of the present invention, Fig. 3 is an explanatory diagram of the optical fiber arrangement before rough winding is applied to the optical fiber group, and Fig. 4 is an inverted assembly. Fig. 5 shows a conventional spiral grooved spacer type optical cape...tensile strength member 2...grooved spacer 3...optical fiber 4...color Separate rough winding 5... Sheath 6... Grooved spacer supply device 7... Optical fiber supply device 8... Optical fiber feeding device 9... Optical fiber storage device 10... Upper winding tape 11...・Explanation port for full fiber arrangement before rough @ is applied to the winder optical fiber group・
Fig. 3 Explanatory diagram of two twisted fibers that are twisted together and four extra lengths.

Claims (4)

[Claims] (1) In an optical cable having a structure in which a plurality of optical fibers are housed in a spiral groove of a grooved spacer having a spiral groove whose direction is periodically reversed on the outer periphery, the plurality of optical fibers are loosely wound to be collectively restrained. An optical cable characterized in that it is formed by forming a group of coated optical fibers. (2) The optical cable according to claim 1, wherein the coarse winding applied to the plurality of optical fibers has a different color for each optical fiber group in which the plurality of optical fibers are collectively bound. (3) After storing a plurality of optical fibers in the spiral groove of a grooved spacer having a spiral groove whose direction is periodically reversed on the outer periphery,
In a method of manufacturing an optical cable in which an optical cable is constructed by applying a top-wrap tape to the outer periphery, the plurality of optical fibers are collectively restrained by a rough winding device while the directions of the plurality of optical fibers are periodically reversed by an optical fiber reversing device. A method for manufacturing an optical cable, comprising the steps of: forming an optical fiber group by applying the rough winding, and storing the coarsely wound optical fiber group in a spiral groove of the spiral grooved spacer. (4) The step of storing the roughly wound optical fiber group in the spiral groove of the spiral grooved spacer includes changing the direction reversal period of the plurality of optical fibers of the optical fiber group in the direction of the spiral groove of the spiral grooved spacer. The optical cable according to claim 3, wherein the optical cable is synchronized with a reversal period, and the reversal direction of the plurality of optical fibers and the reversal direction of the spiral groove of the spiral grooved spacer are set to be opposite to each other. Production method.