JPS62258411A - Optical fiber cable and its production - Google Patents

Abstract

PURPOSE:To effectively produce an optical fiber cable having good connecting workability by forming a retaining winding on plural pieces of optical fiber strands and housing the strand into the spiral grooves of a grooved housing body while forming the units thereof. CONSTITUTION:The strands unit 15 formed by subjecting plural pieces of the optical fiber strands 17 to the retaining winding with tapes 18 are housed into three grooves among the spiral grooves of the grooved housing body 11 consisting of a central tension member 12 and an extruded molding 13 and a slender waterproof member 16 having water absorptive swellability is housed into the remaining one groove. The retaining winding 19 and a sheath 20 are covered on the outside periphery thereof. The production of the optical cable is executed by bundling the plural optical fiber strands 17 by an aggregating machine 22 and winding the tapes 18 supplied from a retaining winding machine 23 thereto. The formed strand units 15 are housed through an eyeboard 24 into the spiral grooves 14 of the grooved housing body 11 supplied from a drum 24 and are taken up on a winder 26.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to an optical fiber cable of a type in which an optical fiber is housed in a spiral groove of a grooved housing.
The present invention relates to a method for manufacturing the same.

[Prior art and its problems]

A slot-type optical fiber cable has been developed as an optical fiber cable that efficiently stores a large number of optical fibers in a narrow space. This cable is equipped with a linear grooved storage body having a spiral groove on the outer periphery, and each of the spiral grooves stores a plurality of optical fiber strands,
Further, the outer periphery of the grooved storage body is wrapped with pressure, if necessary, and then covered with a sheath. As the optical fiber wire, a relatively thin optical fiber having an outer diameter of 125 μm coated with an outer diameter of 250 to 400 μm made of, for example, an ultraviolet curing resin is used. The number of cables accommodated per spiral groove is up to about 12, and the outer diameter of the cable when 100 cables are accommodated is about 16 mm.

However, this type of optical fiber cable has the following drawbacks. That is, if the sheath is removed during cable connection, a large number of optical fibers are taken out at once and separated, making the connection work including identification of the strands complicated. Furthermore, since a plurality of optical fibers are disposed separately within the spiral groove, when tension is applied, the load shared by each optical fiber strand tends to be uneven. Furthermore, as the optical fiber strand density within the spiral groove increases, loss is likely to increase due to mutual intersection of the optical fiber strands.

[Means for solving problems and their effects]

The present invention provides an optical fiber cable that solves the problems of the prior art as described above, and an efficient manufacturing method thereof.

In order to achieve this object, the present invention provides an optical fiber unit by wrapping a plurality of optical fibers around the outer periphery with tape or string, and in this unit state, the helical groove of the grooved storage body It was designed to be stored in. As in the conventional case, the outer periphery of the grooved storage body is covered with a sheath after being wrapped as required.

The spiral groove of the grooved storage body may be an inverted spiral groove in which the direction of the spiral is reversed at every fixed pitch, or a unidirectional spiral groove in which the direction of the spiral is constant. Although a plurality of helical grooves are formed, the optical fiber uni-nod may be housed in all or only a portion of the helical grooves.

It is preferable to use a material that absorbs water and swells when it comes into contact with water for the pressure winding of the optical fiber unit, in order to prevent water from running when the sheath is damaged.

In addition, when storing the optical fiber unit in a part of the multiple spiral grooves of the grooved storage body, a long and thin waterproof member made of water-absorbing and swelling material should be stored in the other spiral grooves. However, this is still preferable in terms of preventing water running when the sheath is damaged.

It is preferable to store the optical fiber strand unit in the helical groove with tensile stress applied in order to stabilize each optical fiber strand within the groove and prevent vibration or slippage.

Optical fiber units can be made by unidirectionally twisting or SZ-twisting multiple optical fibers and then wrapping the outer circumference with tape or string, or by connecting multiple optical fibers in parallel. It is also possible to use a material whose outer periphery is wrapped with tape or string.

The present invention further provides a method for manufacturing an optical fiber cable as described above, which comprises wrapping the outer periphery of a plurality of optical fibers with tape or string to form an optical fiber unit. This method is characterized in that the step of forming the fiber optic fiber unit and the step of storing the optical fiber strand unit in a spiral groove of a long and narrow grooved storage body to form a cable are performed in tandem.

When performing the above two steps in tandem, if the grooved storage body has an inverted spiral groove, the grooved storage body is rotated alternately in the forward and reverse directions while running, so that the optical fiber unit becomes grooved. It is preferable to store the optical fiber unit while keeping the position at which it is wrapped around the storage body constant.

In addition, when the grooved storage body has a unidirectional spiral groove,
The grooved storage body is rotated in one direction while running,
To store an optical fiber unit while keeping the position where the optical fiber unit wraps around a grooved storage body constant.

〔Example〕

FIG. 1 shows an embodiment of an optical fiber cable according to the present invention. In the figure, 11 is the center tension member 12
This is a grooved storage body consisting of an extrusion molded body 13, and this grooved storage body 11 has four spirals at equal intervals on the outer periphery.
14 is formed. FIG. 2 shows the external appearance of the grooved storage body 11.

Among the four helical grooves 14, three of them accommodate the optical fiber strands 5, and the remaining one accommodates an elongated water-absorbing and swelling waterproof member 16. The optical fiber strand unit 15 is a bundle of a plurality of optical fiber strands 17, and the outer periphery of the bundle is wrapped with a tape 18 in an open helical manner. This tape 18 is also made of water-absorbing and swelling material.

Further, the outer periphery of the grooved storage body 11 is provided with a pressure winding 19 as a cable, and the outer periphery is covered with a sheath 20.

When the optical fiber cable is configured as described above, even if the terminal sheath 20 and pressure wrap 19 are removed when connecting the cable, each Uniso H5 is wrapped with tape 18, so that many optical fibers can be connected. The strands 17 do not fall apart, the strands can be easily identified during connection, and the pressure tape 18 can be easily removed, resulting in good connection workability. In addition, since the plurality of optical fiber strands 17 housed in each helix 1l 114 are wrapped tightly with tape 18, when a tensile load is applied, the load shared by each optical fiber strand 17 is equalized, causing wire breakage. This is effective in preventing the optical fibers 17 from crossing each other, and is also effective in suppressing increase in loss.

Also, a waterproof member 16 and a pressure tape 18 for the unit are provided.
The sheath 20
If the cables are damaged and water enters the cable, they will absorb water and swell, preventing water from running along the length of the cable. Examples of water-absorbing and swelling materials include carboxylmethyl cellulose, polyacrylic acid, poval, and polyoxyethylene polymers, which can be used alone or in combination with other materials9. Taking carboxylmethylcellulose polymer as an example, this polymer absorbs about 40 to 100 times its own weight of water,
Swells and becomes a gel.

Next, a method for manufacturing an optical fiber cable according to the present invention will be explained.

FIG. 3 shows an example of this. The plurality of optical fiber elements 117 supplied from the supply bobbin 21 are transferred to the assembly machine 22.
The tape 18 supplied from the pressure winder 23 is wound around the outer periphery of the bundle. The collecting machine 22 may be one that simply collects a plurality of optical fibers 17 in parallel,
It may be twisted in one direction or SZ twisted. In the figure, two sets of the collecting machine 22 and the press winding machine 23 are shown, but as many sets as necessary are provided.

Optical fiber unit 1 formed as above
5 is the spiral a1 of the grooved storage body 11 through the batten 24.
It is stored in 4. Grooved storage body 1 in this embodiment
The first spiral groove 14 is an inverted spiral groove in which the direction of the spiral is reversed every predetermined length. The grooved storage body 11 is supplied from a drum 25, is wound up by a winder 26, and travels. In order to store the optical fiber bare wire 15 in the inverted spiral groove 14 as described above, the batten 24 is kept stationary so that the position where the unit 15 is wound around the grooved storage body 11 is kept constant. , the traveling grooved storage body 11 is rotated alternately in the forward direction and in the reverse direction. This grooved storage body 1
1 rotation is performed by rotating the drum 25 and the winder 26. The rotational speed of the grooved storage body 11 is set to one rotation while the grooved storage body 11 travels by one pitch of the spiral guide.

In this way, the process of forming the optical fiber unit 15 and the process of forming the optical fiber unit 15 and the helical groove 14 of the grooved storage body 11 can be performed.
The steps of accommodating the cable and making it into a cable can be performed in tandem, making it possible to efficiently manufacture the cable.

Note that when a plurality of optical fiber strands 17 are assembled in parallel, if the reversal interval of the spiral conduction is long, a problem of difference in length or twisting of the optical fiber strands may occur within the unit. In that case, it is a good idea to add some twist.

Next, FIG. 4 shows another embodiment of the manufacturing method according to the present invention. The embodiment shown in FIG. 3 uses a grooved storage body having a spiral groove in which the direction of the spiral is reversed every predetermined length longer than the pitch of the spiral groove. As a storage body 11 with a helix al pitch, that is, 3
This is an example in which a groove having a spiral groove in which the direction of the spiral is reversed within 60' is used.

When using such a grooved storage body 11, the grooved storage body 11 is simply allowed to travel, and by alternately rotating the battens 24 in accordance with the direction of the spiral groove 14, the grooved storage body 11 is moved into the spiral groove 114. The optical fiber unit 15 is stored. The forming process of the optical fiber unit 15 is the same as the embodiment shown in FIG.

FIG. 5 shows still another embodiment of the manufacturing method according to the present invention. This embodiment is an example in which a grooved storage body 11 having a unidirectional helix/J114 is used. In this case, the eye board 24 is kept stationary, and the eye board 5 is connected to the grooved storage body 11.
The traveling grooved storage body 11 is rotated in one direction so that the position at which the grooved storage body 11 is wrapped around is kept constant. The grooved storage body 11 is rotated by rotating the drum 25 and the winder 26.

The rotational speed of the grooved storage body 11 is set to one rotation while the grooved storage body 11 travels for one pitch of the spiral guide. Note that the forming process of the optical fiber strand Uniso 1-15 is the same as the embodiment shown in FIG.
When assembling multiple optical fibers in parallel, by twisting them slightly or selecting the assembly position appropriately, problems with differences in length and twisting of the optical fibers within the unit can be avoided. Can be resolved.

The method of this embodiment is suitable for storing an optical fiber unit in a spiral groove of a grooved storage body while applying tensile stress.

〔Effect of the invention〕

As explained above, in the optical fiber cable according to the present invention, since a plurality of optical fiber wires are wrapped and stored in the spiral groove of the grooved storage body, the sheath is removed when the cable is connected. A large number of optical fiber strands do not fall apart even when stripped (the strands can be easily identified, and the pressure winding can be easily removed, making splicing work easier. Since the strands are bundled with pressure winding, when a tensile load is applied, the load shared by each optical fiber strand is equalized, which is effective in preventing breakage, and also regulates the relative position of the optical fibers. This reduces the number of crossings of the optical fibers, which is also effective in suppressing loss increase.

Further, according to the manufacturing method of the present invention, while forming a unit by applying pressure winding to a plurality of optical fiber strands, the unit can be stored in the spiral groove of the grooved storage body. It has the advantage of being able to manufacture cables efficiently.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of an optical fiber cable according to the present invention, FIG. 2 is a perspective view of a grooved storage body in the same cable, and FIGS. 3 to 5 are each an optical fiber according to the present invention. It is an explanatory view showing an example of a cable manufacturing method. 11-grooved storage body, 14-spiral groove, 15-optical fiber strand unit, 16-waterproofing member, 17-optical fiber strand, 18-press winding tape, 20-sheath, 22-collector, 23-presser Winding machine, 24~ batten, 26~ winding machine. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (9)

[Claims] (1) A long and narrow grooved storage body having a plurality of inverted spiral grooves or unidirectional spiral grooves on the outer periphery, and a part or all of the spiral grooves of the grooved storage body are provided with a plurality of optical fiber strands on the outer periphery. An optical fiber cable that stores an optical fiber unit formed by wrapping the fiber with tape or string, and covers the outer periphery of the grooved storage body with a sheath. (2) The optical fiber cable according to claim 1, in which the presser winding of the optical fiber unit is made of a material that absorbs water and swells. (3) The optical fiber cable according to claim 1 or 2, wherein the optical fiber unit is housed in some of the spiral grooves of the grooved storage body. , the other spiral groove houses an elongated waterproof member made of water-absorbing and swelling material. (4) The optical fiber cable according to any one of claims 1 to 3, wherein the optical fiber unit is housed in the helical groove in a state where tensile strain is applied. (5) The optical fiber cable according to any one of claims 1 to 3, wherein the optical fiber unit comprises a plurality of optical fibers twisted in an SZ manner, and then the outer periphery It is made by wrapping it with tape or string. (6) The optical fiber cable according to any one of claims 1 to 4, wherein the optical fiber unit comprises a plurality of optical fibers assembled in parallel. The outer periphery is wrapped with tape or string. (7) Forming an optical fiber unit by wrapping the outer periphery of a plurality of optical fiber strands with tape or string; 1. A method for manufacturing an optical fiber cable, comprising performing in tandem a step of storing the fiber in a spiral groove of a long and narrow grooved storage body to form a cable. (8) The manufacturing method according to claim 7, comprising:
The grooved storage body has an inverted spiral groove, and the grooved storage body is rotated alternately in the forward and reverse directions while running to maintain a constant position at which the optical fiber unit wraps around the grooved storage body. A device that stores optical fiber units while keeping them in a safe place. (9) The manufacturing method according to claim 7, comprising:
The grooved storage body has a one-way spiral groove, and the grooved storage body is rotated in one direction while traveling, and the position where the optical fiber unit wraps around the grooved storage body is kept constant to emit light. A device that stores fiber wire units.