JPS6273216A - Optical fiber cable and its manufacture - Google Patents

Abstract

PURPOSE:To remarkably reduce the cost of cable manufacture by using a slit pipe which has a continuous slit lengthwise. CONSTITUTION:An optical fiber element wire 7 is put in the slit plastic fiber 11 made of, for example, plastic provided with the lengthwise slit and, for example, six slit plastic pipes 11 are put together with a tensile strength body 4; and the outer periphery is fixed by pressure winding 5 and the surface is provided with a cladding 6. In another way, seven slit plastic fibers 11 are put together and fixed by pressure winding 5 and the tensile strength body 4 is arranged outside this optical fiber cable, and the cladding 6 is provided to obtain a potbelly type cable cladding structure. The slit pipe is formed of, for example, HDPE, LDPE, PD, L-LDPE, nylon, polyester, etc.

Description

Detailed Description of the Invention: An optical fiber having a structure in which a single optical fiber or a plurality of optical fibers are housed in a slit pipe having continuous divisions in the longitudinal direction, and one or more slit pipes are assembled together with a tensile strength member. An economical method that can be carried out in one continuous process by inserting the optical fiber into the fiber cable and slit pipe through the slit, assembling the pipe or the pipe and tensile strength body, and applying an outer sheath to form a cable. Method of manufacturing optical fiber cable.

[Industrial application field]

The present invention relates to a low-cost optical fiber cable and a method for manufacturing the same, and in particular to an optical fiber cable that can be manufactured in one continuous process from storing optical fiber pipes, assembling pipes or pipes and tensile strength members, and covering the outer sheath. The present invention relates to the structure of a fiber gaple and its manufacturing method.

[Conventional technology]

This type of optical fiber cable has a structure with excellent quality and workability in optical fiber bundle type cables such as conventional subscriber optical fiber cables.
These have been proposed to solve the problem of low cost, and typical examples are There is a cable. Here, optical fiber refers to an optical fiber coated with plastic, generally silicone or ultraviolet curing resin, to protect the optical fiber and eliminate unnecessary modes during the first drawing stage of the optical fiber. is easy to handle,
An optical fiber coated with plastic, typically nylon or ultraviolet curable resin, for improved mechanical properties.

FIG. 6 shows the cross-sectional structure of the optical fiber wire assembly type cable. 1 is an optical fiber wire, 2 and 3 are 5-fiber units 1 to 4
5 is a tensile strength member, 5 is a presser winding, and 6 is an outer cover. Note that the current subscriber optical fiber cable is an optical fiber aggregate type optical fiber cable in which one optical fiber strand is composed of an optical fiber core wire.

FIG. 7 shows the cross-sectional structure of the optical fiber strand assembly spacer type cable. 5 is a presser winding, 6 is an outer sheath, 7 is an optical fiber wire, 8 is a PE spacer with a spiral groove, and 9 is a tensile strength member inside the spacer.

Figure 8 shows the cross-sectional structure of a multi-core loose tube type cable. 4 is a tensile strength member, 5 is a presser winding, 6 is a jacket, 7 is an optical fiber wire, and 10 is a loose tube core wire.

[Problem that the invention seeks to solve]

Since the optical fiber integrated cable has a structure of a subscriber optical cable using a nylon core wire which originally has excellent lateral pressure characteristics, the optical fiber strands are also required to have good lateral pressure characteristics. That is, it is difficult to use the optical fiber itself, and it is necessary to apply some kind of protective layer, which has the drawback that a reduction in price cannot be expected.

Optical fiber aggregate spacer type cable has a structure in which multiple optical fibers are housed in each groove of the spacer, and since the optical fibers are completely protected by the spacer, the optical fibers are Because it does not require much lateral pressure characteristics, the optical fiber can be stored as is.
Although it has the advantage of being able to omit the core assembly process and also eliminate the unitization process when compared to optical fiber assembly cables, there are two main issues in the cable production process: assembly and outer sheathing. There is still a problem in trying to lower the price, as it is inevitable that the price will be lower.

Multi-core loose tube type game sols! The disadvantage of the IIJ crown-making process is that it involves multiple steps, including the steps of creating one culm, gathering, and coating. If we take the equipment into consideration, it is not impossible to produce the product by using a culm, but since it involves a multi-fiber loose tube type cable structure, it requires a considerable amount of technical effort and production costs, as well as equipment costs. There is a problem that this is expected to increase in price, which goes against the essential purpose of increasing prices.

[Problem 6. [Means for Solving] In order to solve the conventional problems, the present invention uses a pipe for storing a single fiber or a plurality of optical fibers as a pipe with a slit that is continuous in the longitudinal direction.
The optical fiber cable structure is characterized by a manufacturing method and an optical fiber cable structure in which the steps of inserting into a slit pipe, fitting, and forming an outer sheath into a cable are performed continuously in one step.

[For production]

The present invention provides a cable structure and method for manufacturing the optical fiber assembly type cable continuously in one process, which can significantly reduce the cost of making the cable. This will be explained in detail below with reference to the drawings.

〔Example〕

FIGS. 1a and 1b show cross-sectional structures of embodiments of optical fiber cables according to the present invention.

In Fig. J a, an optical fiber 7 is housed in a slitted plastic pipe 11 made of plastic, for example, with a split in the longitudinal direction, and a plurality of slitted plastic pipes II, in this example, 6 It has a structure in which the core is gathered together with a tensile strength member 4, and the outer periphery is fixed with a presser winding 5, and a jacket 6 is applied to the surface.

As shown in Fig. 1b, a plastic pipe 11 with slits containing a bare optical fiber 7 is assembled into 7 cores, and an optical fiber cable is fixed with a presser winding 5, and an outer jacket with a tensile strength member 4 arranged outside the optical fiber cable is attached. This is an example of a Daruma-type cable jacket structure that has been subjected to 6.

FIG. 2 shows still another embodiment of the present invention, in which the optical fiber 11y housed in the slitted plastic pipe 11 is a ribbon fiber.In this embodiment, the optical fiber 7 shown in FIG. This is an example in which 5-fiber tape core wires 12 arranged in a core tape shape are stacked and housed in 4-fiber cores in a plastic pipe 11 with slits.

The material for forming the pipe with slits is Hr.
) l) E, I-r) Pru, PD, L-Lr) P) 已.

Applicable materials include nylon and polyester. Furthermore, the method of assembling the pipes with slits into which the optical fibers are inserted and accommodated may be either with one twist in one direction or without twisting. This is because even if the pipe itself is not twisted, since the optical fiber wire is loosely housed in the pipe, it can be considered that no torsional strain is applied to the optical fiber wire. A simpler configuration for manufacturing equipment is SZ twisting than unidirectional twisting. In other words, the part of the batten in the Hayabusa culm is in the S direction (right-handed twist) and in the Z direction (left-handed twist).
By alternately twisting each wire, the rotating part can be made compact, which is advantageous in terms of device structure and manufacturing speed. Further, in this SZ chamber assembly method, the part where the optical fiber wire is inserted into the slit pipe does not rotate, so visual monitoring is possible, which is an advantage in manufacturing.

A method of manufacturing an optical fiber cable according to the present invention will be explained with reference to FIG. The structure of the optical fiber cable produced by the manufacturing method shown in FIG. 4 corresponds to the example of the optical fiber cable having the cross-sectional structure shown in FIG. 1a.

The plastic pipe 14 is fed out from the plastic pipe supply 13, and the optical fiber wire I5 is inserted into the plastic pipe 14 using the optical fiber wire insertion section 25.

The plastic pipe 14 may be supplied from the plastic pipe supply 13 with a slit in advance, or a slit may be made in the plastic pipe 14 at a position in front of the optical fiber wire insertion section 25.

Although not shown in this case, the optical fiber wire insertion section 25
It is better to install a jig for slitting the plastic pipe 14 with a cutter or the like at the inlet of the pipe, and a capstan for feeding out the slitted plastic pipe 18 at the exit r-1 to reduce the tension at the time of slitting. The optical fiber wire insertion section 25, an explanatory view of which is shown in FIG. This allows the optical fiber 15 to be easily inserted into the slit-shaped plastic pipe.

The plastic pipe 14 containing the optical fiber element 11i115 is twisted in the S1 direction and the Z1 direction at the batten part 20 through the middle rc-c of the tensile strength body supplied from the tensile strength body supply 19. At this time, in order to prevent the rotation and vibration of the opening plate part 20 from affecting the optical fiber insertion part 25, the position where the plurality of optical fibers 15 are collected and fed into the optical fiber insertion part 17 and For example, place the plastic pipe 14 into which the fiber wire 15 is inserted and housed in the handling section 20. Proper installation of a guide 1'J-ra 16 such as a J-1 roller or a dancer roller is required.

S1, Z-twisted and assembled plastic pipe tube 14
For example, a presser winding 21 is applied to prevent any unraveling, a collective core 22 is formed, and a PR jacket is applied to the outer periphery from an extrusion crosshead 23 to produce a cable 24.

It should be noted that a heat insulating tape may be added vertically to the outer periphery of the presser wrap 21, and instead of the PE outer covering applied to the outer periphery of the collective core 22, various types such as L, AP sheath or P■C sheath may be used. An outer covering may be applied. Further, as another embodiment, as shown in the cross-sectional structure in FIG.

As explained above with reference to FIG. 4, with the structure of the optical fiber cable according to the present invention, it is possible to manufacture the cable 24 in the flow of supplying the optical fiber 15 and then proceeding to the culm.

It should be noted that it is obvious that the tape-encased optical fiber cable of the present invention, the cross-sectional structure of which is shown in FIG. 2, can be manufactured by basically the same method as the manufacturing process shown in FIG. 4, without the need for detailed explanation.

〔Effect of the invention〕

As mentioned above, this kind of conventional fiber optic cable! ! The manufacturing method is: optical fiber material - ÷ inspection - = wire drawing (
Optical fiber bare wire) - Inspection - Nylon coated fW (Optical fiber core wire) - One inspection - Unit 1 - Inspection - 1 = Twisting - Inspection - Outer covering - Inspection In contrast,
The present invention consists of optical fiber lυ material - inspection - drawing (optical fiber raw wire) - one inspection - cable production - one inspection, and clearly the optical fiber cable of the present invention has a cable structure that can realize low cost. It is possible to obtain an optical fiber strand assembly type cable by a manufacturing method using continuous steps, which has a remarkable effect on cost reduction.

[Brief explanation of drawings]

1a and 1b are cross-sectional structures of an embodiment of the optical fiber cable of the present invention, FIG. 2 is a cross-sectional structure of an embodiment of the tape-wrapped optical fiber cable of the present invention, and FIG. 3 is an implementation of the embodiment of FIG. 2. 4 is an explanatory diagram of the manufacturing process of the optical fiber cable of the present invention, FIG. 5 is an explanatory diagram of the optical fiber insertion part in FIG. 4, and FIGS. 6 to 8
The figures show the cross-sectional structures of a conventional optical fiber strand aggregate type cable, an optical fiber strand spacer type cable, and a multi-core loose tube type cable, respectively. 1.7... Optical fiber wire, 2, 3... 5-core unit, 4... Tensile strength body, 5... Presser winding, 6... Outer cover, 8... Spiral grooved p E spacer, 9... Tensile strength member in spacer, 10... Loose tube core wire, 11.
...Plastic pipe with slit, 12...5-core tape core wire, 13...Plastic pipe supply, 1
4...Plastic pipe, ]5... Optical fiber wire, 16... Guide roller, 17... Optical fiber wire guide pipe, ]8... Plastic pipe with slit, 19... Tensile strength ply, 20... batten part, 21... presser winding, 22... collective core, 23...
・Extrusion crosshead, 24...cable, 25...
Optical fiber wire insertion part

Claims (5)

[Claims] (1) In an optical fiber cable made up of one or more pipes housing a single core or multiple optical fibers, or the pipes and a tensile strength body, the pipes are continuous in the longitudinal direction. An optical fiber cable comprising a slit pipe. (2) The optical fiber cable according to claim 1, wherein the pipe assembly has a structure using SZ twist. (3) The optical fiber cable according to claim 1, wherein the optical fiber housed in the pipe is made of a single wire. (4) The optical fiber cable according to claim 1, wherein the optical fibers housed in the pipe are composed of double wires arranged in a tape-like manner and whose outer periphery is covered and fixed. (5) A single optical fiber or a plurality of optical fibers are housed in a pipe, one or more of the pipes, or the pipe and a tensile strength body are gathered together and pressed and wound, and an outer sheath is applied to the outer periphery. In an optical fiber cable manufacturing method for forming an optical fiber cable, the pipe may be a pipe with slits that has cracks in the longitudinal direction in advance, or a pipe with cracks in the longitudinal direction during the process after being unwound from the supply. a step of inserting an optical fiber into the crack in the slitted pipe using a slitted pipe; and a step of collecting the slitted pipe or collecting the slitted pipe and the tensile strength body together and applying pressure winding to form the assembly. A method for manufacturing an optical fiber cable, characterized in that a forming step and a step of applying a jacket to the outer periphery of the aggregate are performed in one continuous step.