JPS6087307A - Flat optical cable - Google Patents

Abstract

PURPOSE:To improve productivity and to improve operability by forming a ribbon unit of multicore optical fibers arrayed in parallel and united together with ultraviolet-ray setting resin, etc., and assembling plural ribbon units flatly in one body with ultraviolet-ray setting resin, etc. CONSTITUTION:The ribbon unit 2 is formed by bundling 5- or 10-core optical fibers in a tape shape has a 50-100kg/mm.<2> Young's modulus and is covered thickly with ultraviolet-ray setting resin having a 50-100kg/mm.<2> Young's modulus to an about tens of mum thickness, and two ribbon unit assemblies each consisting of three ribbon units 2 are stacked and stored loosely in the rectangular space formed in a cable sheath 1. The assembly coating 5 of the ribbon unit assembly uses the ultraviolet-ray setting resin having the smaller Young's modulus (e.g. <=10kg/mm.<2>) than the ribbon unit coating, so the ribbon units are separated easily from each other when necessary and the operability is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of a high-density and compact multi-core optical fiber cable for communication that can be manufactured economically using a simple manufacturing method. 11ti side, l is a polyethylene jacket, 2 is a ribbon unit, and 8 is a tensile strength member.

This optical cable has a structure in which two ribbon units 2 are housed in a rectangular space formed by a polyethylene jacket 1, and tensile strength members 8 are provided at both ends of the cable. The feature of this optical cable is that it only takes one process to turn the ribbon unit into a cable.
This is advantageous for economicalization of optical cables.

However, increasing the number of optical fibers in this type of cable has been difficult in terms of manufacturing and technology. In other words, stacking a large number of ribbon units is one way to increase the number of fibers, but since the cable does not have a twisted structure, when the cable is bent, the unit on the center of curvature receives compressive strain, and the unit on the opposite side receives compressive strain. Since the unit is subject to stretching strain, there are many problems with respect to the reliability of the optical fiber.

Another possible method is to increase the number of fibers in the ribbon unit, but this approach has limitations in terms of manufacturing workability and manufacturing yield. That is, in order to manufacture a multi-core ribbon unit, it is necessary to line up as many payout bins as the number of cores, which is difficult to assemble due to poor operability. Furthermore, if the number of core wires in Ripon Units is too large, there is a drawback that workability and yield during batch connection are reduced.

In order to eliminate the above-mentioned drawbacks, the present invention integrates ribbon units with approximately 5 or 10 fibers, which are easy to manufacture, using a resin with a small Young's modulus, so that the ribbon units can be easily separated from each other when connected, and are easy to operate. The purpose of the present invention is to provide a flat optical cable that facilitates Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is a sectional view of a ribbon unit, and FIGS. 3 and 4 are diagrams showing embodiments of the present invention, in which 1 is a cable jacket, 2 is a ribbon unit, 2a is an optical fiber, 2b is a fiber coating, 2c is ribbon unit covering, 8
is a tensile strength member, 4 is a rectangular space, and 5 is a ribbon unit collective covering.

The ribbon unit 2 is formed by converging 5 or 10 optical fibers into a tape shape. fiber cover g2b
The optical fiber wire with
Alternatively, the ribbon unit y-2c is coated with two layers, and the Young's modulus is 50 to 1001 cg/m-
The ultraviolet curing resin is used, and the thickness is only a few tens of micrometers.

FIG. 8 is a sectional view of a cable in which two ribbon unit assemblies each made of three ribbon units 2 are overlapped and loosely housed in a rectangular space 4 formed in the cable jacket 1. The ribbon unit aggregate coating 5 has a Young's modulus (for example, 1071) smaller than that of the ribbon unit coating 92C.
9/- or less) was used.

Therefore, the ribbon units can be easily separated from each other as necessary. Further, in order to easily identify the core wires, different colors are applied to two ribbon unit assemblies along the long axis of the ribbon unit assemblies 5 at one end of the ribbon unit assemblies 9Ji5. At both ends of the cable sheath 1, which has a flat cross-sectional shape, this cable sheath 1 is provided.
A tensile strength member is placed along the long axis of the

Due to the arrangement 6 of the rectangular space 4 and the tensile strength members 8, the cable can be easily bent in the vertical direction of the paper, but it is difficult to bend in the horizontal direction of the paper.

FIG. 4 shows a cross-sectional view of the ribbon unit assembly when the ribbon unit assembly is folded into yw portions having a small Young's modulus and accommodated in the rectangular space 4. One end of this ribbon unit or knit assembly is colored in the longitudinal direction, making it easy to identify the core wires.

FIG. 5 shows a case in which two folded ribbon unit aggregates are stacked one on top of the other. In this case, the core wires can be easily identified, and the number of ribbon units in the rectangular space 4 increases, making it possible to increase the strength of the cable.

As explained above, according to the present invention, five
By using a ribbon unit assembly in which a plurality of core or 10-fiber ribbon units are assembled in a flat shape, a high-density optical cable that is easy to manufacture can be obtained, and economical efficiency can be achieved. In other words, in order to increase the number of fibers in a flat optical cable, it is possible to increase the number of fibers included in the ribbon unit, but ribbon units with multiple fibers such as 80 or 50 fibers are not easy to manufacture. However, the yield will decrease. However, according to the present invention, it is possible to obtain a substantially multi-core unit that is superior in terms of manufacturing workability and yield. In addition, the ribbon unit with 5 cores or 10 cores is
If we use the current manufacturing technology, we can easily make a real sister.

On the other hand, when connecting flat optical cables, ribbon unit aggregates must be connected to each other. At this time, if the resin used to form the ribbon unit assembly is softer than the coating resin of the ribbon unit, the ribbon unit can be easily separated, which has the advantage of improving workability.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional flat optical cable, FIG. 2 is a sectional view of a ribbon unit, FIG. 8 is an embodiment of the present invention, and FIGS. 4 and 5 are other embodiments of the present invention. It is a diagram. l...Cable jacket, 2...Ribbon unit), 2a
'・. Optical fiber, gb, ・Fiber@m520... Ribbon unit coating, 8... Tensile strength body, 4... Rectangular space wire 5... Ribbon unit collective coating.

Claims (1)

[Scope of Claims] L Tensile strength members are disposed along the long axis of the cable jacket having a flat cross-sectional shape, and are located at both ends of the cable jacket, and the inside of the jacket has a rectangular shape. ~In a flat optical cable consisting of a space formed on one side and a plurality of optical fibers assembled within this space, the multiple optical fibers are aligned in parallel, integrated with ultraviolet curing resin, etc., and converged into a tape shape. A ribbon unit assembly is constructed by integrating several grains of the ribbon unit using a ribbon unit assembly resin such as an ultraviolet curing resin so that they are lined up approximately in a straight line from the center of the optical fiber.
A flat optical cable characterized by being housed in one or more laminated layers. i. The 7-rat optical cable according to claim 1, wherein the Young's modulus of the ribbon unit assembly resin is smaller than the Young's modulus of the ribbon unit coating resin. & A flat optical cable Q according to claim 1 or 2, characterized in that the ribbon unit assembly is bent into a U-shape.