| 摘要 |
PURPOSE:To realize an optical fiber cable which does not keep any tension applied when optical fibers are twisted together to make the optical fiber cable and does not transmit any extending force to the fibers even when the cable is extended, by making an arrangement that the optical fibers are twisted together so that they are not entangled with the center core of the tension member, etc., but under a floating condition. CONSTITUTION:Optical fibers 2 are twisted together under a condition where they are rather inscribed in a tape wound layer 4 than closely contacted with a pipe- like core body 10. When such arrangement is made, the optical fibers 2 come nearer to the axis in case where the whole cable is extended, and, therefore, no tension is applied to the optical fibers 2. In addition to the above, the tension applied when the optical fibers were twisted together do not remain in this cable. Even when a very weak tension is applied to this cable, the optical fibers come nearer to the axis and the tension is relieved. Because the looseness of the optical fibers, even when the cable is extended when tension is applied to the cable, the tension is not applied directly to the optical cables but applied only after a condition, where the optical fibers 2 circumscribe about the core body 10, is reached. |
