JPH071605Y2 - Tape core type optical fiber cable - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an optical fiber cable of the tape core type.

[Prior Art] As shown in FIG. 3, an optical fiber tape core wire that constitutes a conventional tape core fiber type optical fiber cable has an optical fiber 1 having a coating 2 on its outer periphery in parallel, for example, 5 cores. They are arranged side by side and a collective coating 3 is applied to their outer circumferences.

As shown in FIG. 4, a conventional tape core type optical fiber cable has a plurality of laminated layers in a groove 7 of a spacer 6 having a tensile strength member 5 around the optical fiber tape core wire 4 configured as described above. Has been housed. In the figure, 8 is a presser winding, and 9 is a sheath.

[Problems to be Solved by the Invention] In the above-described conventional optical fiber tape core wire and cable structure, since the thermal expansion coefficient of the tensile strength member and that of the optical fiber are different, strain is likely to be applied to the optical fiber due to temperature change. Especially when the tensile strength member 5 is a steel wire or a steel twisted wire, the tensile strength member is 1.1 × 10 ^-5 / de for the linear expansion coefficient of the optical fiber of 5 × 10 ^-7 / deg.
Since it is greatly different from g, elongation strain occurs in the optical fiber at high temperature, and compression strain or sag occurs at low temperature. If these phenomena are uniform in the longitudinal direction, no inconvenience will occur for the optical fiber, but if these phenomena are concentrated locally,
It shortens the life of the optical fiber and increases the transmission loss.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a tape optical fiber cable capable of improving temperature characteristics.

[Means for Solving the Problems] The above object is to arrange a rigid body in parallel with at least one side end of a plurality of optical fibers arranged in parallel, and to arrange the side surface of the optical fiber tape core wire on the side of the rigid body with the spacer. This is achieved by adhesive fixing to the inner wall of the groove.

[Operation] Since the rigid body is arranged side by side at one end of the plurality of optical fibers arranged side by side, and the side surface of the optical fiber tape core wire on the side of the rigid body is adhesively fixed to the inner wall of the groove of the spacer. The strain due to the temperature inside the tape core wire is small, and the strain due to the temperature from the tensile strength body or the spacer is not concentrated at one place, and the temperature characteristics of the tape core type optical fiber cable can be improved.

[Embodiment] The present invention will be described below based on the illustrated embodiment. 1 and 2 show an embodiment of the present invention.
Since the same parts as those of the conventional one are designated by the same reference numerals, the description thereof will be omitted. In this embodiment, a rigid body 10 is arranged side by side at one end of a plurality of optical fibers 1 arranged side by side, and is bonded to the inner wall of the groove 7 of the side surface spacer 6 of the optical fiber tape core wire 4a on the side of the rigid body. . By doing so, the strain due to the temperature in the optical fiber tape core wire 4a is small, and the strain due to the temperature from the tensile strength member 5 and the spacer 6 is not concentrated in one place, and the temperature characteristic can be improved. It is possible to obtain the optical fiber cable of the tape core type.

That is, as shown in FIG. 1, the optical fiber ribbon 4a has a structure in which one of the corners of the optical fiber ribbon shown in FIG. As shown in FIG. 2, the cable structure is such that when the optical fiber ribbon 4a is accommodated in the groove 7 of the spacer 6, the side of the optical fiber ribbon 4a on which the rigid body 10 is inserted is groove 7. It is glued to the inner wall of the.

When FRP is used as the rigid body 10, FRP is an optical fiber 1
Since the coefficient of linear expansion is almost the same and the rigidity is high, the strain due to temperature in the optical fiber ribbon 4a is small. Further, strain due to temperature from the tensile strength member 5 (when a steel wire or a steel stranded wire) or the spacer 6 having a large linear expansion coefficient is not concentrated in one place because the FRP rigidity is large.

Further, as shown in FIG. 2, the groove 7 of the spacer 6 is
And the optical fiber ribbon 4a with an adhesive or an adhesive tape 11
And the like, the rigidity of the rigid body 10 is utilized to reduce the difference in the linear expansion coefficient between the optical fiber 1 and the tensile strength body 5 and the spacer 6, and the optical fiber 1 due to temperature change
The local strain concentration is avoided and the strain is evenly applied in the longitudinal direction.

As described above, according to this embodiment, it is possible to improve the conventional temperature characteristic, that is, increase in transmission loss at low temperature.

Although the optical fiber ribbons 4a are stacked and housed in the groove 7, care must be taken so that the rigid bodies 10 in the respective optical fibers 4a are on the same side. Therefore, if the coating 3 of the core wire 4a on the side of the rigid body 10 is provided with a color mark (line) and the core wires 4a are laminated so that the color marks are on the same side, the manufacturing work Will be easier.

The rigid bodies 10 may be arranged side by side on both sides of the optical fiber, but if both sides of the optical fiber tape core wire 4a are adhered to the inner wall surface of the groove 7, it becomes difficult to take out the core wire 4a. Even in this case, it is desirable to adhere only one side surface of the core wire 4a to the inner wall of the groove.

[Advantages of the Invention] As described above, the present invention replaces one end of a plurality of optical fibers arranged in parallel with a rigid body, and bonds the optical fiber tape core wire on the rigid body side to a groove of a tensile strength body or a spacer. Therefore, the strain due to the temperature in the optical fiber tape core wire is small, and the strain due to the temperature from the tensile strength member or the spacer is not concentrated in one place, and the temperature characteristics can be improved. It is possible to obtain a core-fiber type optical fiber cable.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of an optical fiber ribbon of an embodiment of a tape optical fiber cable of the present invention, and FIG. 2 is an embodiment of a tape optical fiber cable of the present invention. An example vertical side view, FIG. 3 is a vertical side view of an optical fiber tape core wire of a conventional tape core type optical fiber cable, and FIG. 4 is a vertical side view of a conventional tape core type optical fiber cable. It is a figure. 1: optical fiber, 4a: optical fiber tape core wire, 5: strength member, 6: spacer, 7: groove, 10: rigid member.

Claims (1)

[Scope of utility model registration request] 1. A tape core type optical fiber cable in which an optical fiber tape core wire covering a plurality of optical fibers arranged in parallel is housed in a groove provided on an outer periphery of a spacer, wherein the optical fiber tape core wires are arranged in parallel. A tape in which a rigid body is arranged in parallel at least at one side end of a plurality of optical fibers, and the side surface of the optical fiber tape core wire on the rigid body side is adhesively fixed to the inner wall of the groove of the spacer. Core type optical fiber cable.