JPS58117509A - Manufacture of optical fiber cable - Google Patents

Abstract

PURPOSE:To improve the reliability of an optical fiber core to elongation by storing optical fiber cores in a spacer while such tensile force that elongation is less than an elastic limit is applied, and winding them without applying tensile force to assembled cores from a drawing device. CONSTITUTION:The grooved spacer 2 is fed from a spacer unwinding device 1 to an optical fiber core device 4 to equip optical fiber cores 3 in grooves of the grooved spacer 2, thus forming a fiber core 5. Such tensild force that the elongation of the core is less than its elastic limit is applied to the grooved spacer 2 between the spacer unwinding device 1 and drawing device 6. Between the drawing device 6 and a take-up device 7, only tensile force which is small enough to disregare the elongation of the spacer 2 is applied. The grooved spacer from the drawing device 6 contracts lengthwise because the tensile force is released, and the optical fiber cores 3 are equipped loosely in the grooves 2-1 of the spacer.

Description

[Detailed Description of the Invention] Aiming to improve the reliability of nine-fiber core wire,
1. Concerning the manufacturing method of optical fiber cables, nine-fiber fibers have a small allowable elongation rate with respect to tension and are brittle against various types of stress. cable elongation caused by changes in temperature after installation, etc., have an adverse effect on the optical fiber, and the life of the optical fiber is significantly shortened. This problem is a major issue in the practical application of optical fiber cables, and in the past efforts have been made to solve it mainly by improving cable installation methods. Regarding a method of manufacturing an optical fiber cable having a structure in which no elongation is applied to the wire, in a method of twisting and assembling an optical fiber cable having a structure in which the optical fiber core is housed in a spacer having a sufficient storage space, a spacer feeding device is provided. The entire optical fiber core is housed in the spacer with tension applied to the spacer to keep its deflection below the elastic limit between the pulling device and the collecting device, and after leaving the collecting device, it is returned to the collecting core. FIG. 1 shows a specific example of the method of the present invention, which relates to a method of manufacturing an optical fiber cable characterized by winding without applying tension.

A grooved spacer 2 is fed from a spacer feeding device 1 to an optical fiber core device 4, and an optical fiber core 3 is installed in the groove of the grooved spacer 2 to form a fiber core 5.

The optical fiber mounting device 4 can operate in synchronization with the pulling device 6 so as to follow the fluctuation of the helical pitch of the groove of the grooved spacer 2 and smoothly install the optical fiber into the groove. 1. Between the spacer feeding device 1 and the take-up device 6, tension is applied to the grooved spacer 2 so that the outer part of the spacer 2 is kept below the elastic limit. As shown in FIG. 2 (,, i), the cross section of the fiber core 5 up to (point A in FIG. 1) is eroded by the tension within the elastic limit. Groove 2 of grooved spacer 2 in the grooved state
An optical fiber core 6 is attached to the bottom of the -1. .

Next, between the -C1 take-up device 6 and the take-up device 7, only a tension is applied to a value such that the groaning of the grooved spacer 2 can be ignored, for example, o, o1% or less.

After leaving this pulling device 6 (point B in Figure 1), the tension is released and the grooved spacer shrinks in the length direction, so that the light emitted as shown in Figure 2(b). The fiber core will be installed slackly in the groove 2-1 of the spacer. In order to prevent the optical fiber core from protruding from the groove in this state, the pulling device 6 is used.
A pressure winding device may be added between the fiber core and the winding device 7 to perform pressure winding around the outer periphery of the fiber core.

FIG. 3 shows a cross section of a fiber core manufactured in the same manner as above using a spacer of another shape. That is, the U-shaped spacer 8 is assembled together with the inclusion 9 and the tensile strength member 1o, and the optical fiber core 6 is installed in the U-shaped spacer 8 so as to be slack. In this case, a tension within the elastic limit is applied to the U-shaped spacer 8 between the feeding device and the take-up device 6 of the U-shaped spacer 8 added to the cage of the collecting device that is normally used. Proceed as shown.

For a grooved spacer with an outer diameter of 5 mm, if the spacer material is semi-hard aluminum, the tension is 0.2% at 80 Kg.
It has been found through experiments that a groan within the elastic limit of 1 to 2% occurs under the same tension in the case of polyethylene.

[Brief explanation of drawings]

FIG. 1 is a diagram schematically showing the method of the present invention, and FIGS. 2 and 6 are cross-sectional views of a fiber core obtained by the present invention. Agents 1) Akira’s agent Ryo Hagiwara −

Claims (1)

[Claims] 1. In a method of twisting and gathering optical fiber cables having a structure in which optical fiber cores are housed in a spacer having a sufficient storage space, the fibers are stretched smoothly between a spacer feeding device and a gathering core pulling device. One of the characteristics is that the optical fiber core is housed in the spacer and the aggregated core V is wound without applying tension after leaving the take-off device. 4. Method of manufacturing optical fiber cable 1.