PRODUCTION OF OPTICAL FIBER CABLE

摘要

PROBLEM TO BE SOLVED: To dispense with the weaker force for retaining twist direction inverting parts at the time of subjecting square groove segments to S-Z twisting by forming these square groove segments having such bends that the apertures of the segments exist on an outer side and the groove bottom sides exist on an inner side and specifying the radius of bending of these bends. SOLUTION: The square groove segment having such bends that the apertures of the segments exist on the outer side and the groove bottom side exist on the inner side and having the radius R of bending of the bends within the range expressed by the equation: 0.7(1/r)(P/θ)2<=R<=1.5(1/r)(P/θ)2 is used. In the equation, P denotes the inversion pitch (the distance between the adjacent twist direction inversion parts) of the S-Z twisting of the square groove segment; (r) denotes the distance from the center of a central member to the center of the groove bottom of the square groove segment.θdenotes the inversion angle of the S-Z twisting of the square groove segments. The force to retain the twist direction inversion parts at the time of S-Z twisting may be made weaker than heretofore and the production of the cable is made easy.