PURPOSE: To obtain an optical fiber cable of a long life against breakage easily by containing optical fiber cores in the grooves provided on the outside circumference of a rubber-like elastic body of a long size and providing allowances for elongation to the optical fiber cores despite elongation of the rubber-like elastic body.
CONSTITUTION: Plural lines of spiral grooves 2 are provided on the outside circumference of a long sized elastic body 1 of a circular section which is rubber or the like having, for example, ≥200% elongation in such a way that the depth and width of the grooves remain smaller than the outside diameter of optical fiber cores 3 at the max. elongation generated in an optical fiber cable. After the cores are inserted into said grooves 2, the tapes 4 laminated with metallic tapes 4A and thin plastic layers 4B on the outside thereof are coated thereon and further the outside circumference of the tapes 4 are extrusion coated with plastic tapes 5 to melt stick said tapes to the layers 4B, whereby a cable sheath 6 is provided. Even when the long sized rubber-like elastic body elongates, there are allowances in the extension of the cores 3 and the cores restore the original state when tension is released. Thus the optical fiber cable of a long life is obtained.
NEGISHI YUKIYASU
HONDOU HIROTOSHI
FURUKAWA ELECTRIC CO LTD
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