OPTICAL OUTDOOR WIRE ASSEMBLED TYPE CABLE AND METHOD FOR PULLING DOWN OPTICAL FIBER

摘要

PROBLEM TO BE SOLVED: To embody a cost-effective and efficient method for leading in optical fibers to subscriber houses from an optical cable. SOLUTION: The novel cable formed by housing optical outdoor wires 17 packaging one to two pieces of single core coated optical fibers and assembling plural pieces of pipes 33 by twisting is used. This cable is strung at electric poles of plural spans. The optical outdoor wires 17 of the length necessary for leading in or the length necessary for leading in and indoor wiring are withdrawn from the pipes in the cable at the poles near the subscribers in mid-way of the optical outdoor wire assembled type cable or the points near the subscribers and are strung and wires to the respective subscribers when a demand arises. The cable is designed by using the applicable force on the poles, the leading-in length and coefft. of friction, of the optical outdoor wires 17 from the pipes 3, the weight of the optical outdoor wires 17 per unit length and the assembling pitch and spiral radius of the pipes at the time of producing such cable.