CABLE LAYING METHOD

PROBLEM TO BE SOLVED: To lay high-rigidity cables automatically, without posting a worker for each intermediate tracting machine, by controlling the traction speed of a drawing machine so that an output signal from a tension sensor may be a second target value, in a cable traction process. SOLUTION: A central control unit 15a compute the output signal difference between a traction rope tension output signal and a cable tension output signal, and computes a second target value by adding this difference to a first target value. If the first target value is changed over to the second target value, the central control unit 15a outputs a cable speed command signal S20 for controlling the traction speed of an intermediate tracting machine automatically to a motor control unit 15b, so that an output signal S from the tension sensor 20 of an intermediate tracting machine may be the second target value, and its cable drawing speed is automatically controlled. Consequently, it becomes possible to lay high-rigidity cables automatically and to decrease the working force, since rigidity differences can be canceled automatically, when substances to be drawn having rigidity differences are tracted continuously.