TWISTING DETECTOR FOR WIRE AND EXTENDING METHOD FOR OPTICAL FIBER COMPOSITE AERIAL GROUND LINE USING THE SAME

PURPOSE:To prevent wires from generating twisting during extension by utilizing variations in a resistance value due to the movement of a slider. CONSTITUTION:When wires 20 are twisted, a slider 3 moves in response to the twisting by a relative relation while sliding a resistor 4. A current flows from a terminal 7' to the resistor 4, and is input from a terminal 7 through the slider 3, a post 2, fittings 1 and a jumper 6 to an amplifier B. Since the resistance value of the resistor 4 between the terminal 7' and the slider 3 is varied in response to a twisting angle of the wires 20 due to the twisting, the twisting angle of the wires 20 is known by the resistance value. Its twisting direction can be also known by selecting the terminal 7' or 7''. When the thus obtained result is transmitted from an oscillator C through an antenna 10 and received by a receiver, not shown, on the ground, the twisting state of the wires 20 can be detected in real time. Thus, since the twisting speed and direc tion of the wires during the intermediate of the twisting can be continuously and accurately known, an accident can be prevented by coping with it immediate ly if there arises the fear of an excessive twisting of the wires.