Abstract: The controlling apparatus includes a wire supplying sensor 18 for detecting a number of rotations of a wire supplying motor 8, a wire twisting sensor 49 for detecting actuation of a loaded torque detecting mechanism c, and a return position detecting sensor 38 for detecting that a wire twisting mechanism b is located at a predetermined waiting position. In response to an output signal from the wire supplying sensor 18, the controlling apparatus stops rotation of a wire supplying motor 7a and rotationally drives a wire twisting motor 7b. In addition, in response to an output signal from the wire twisting sensor 49, the controlling apparatus shifts rotation of the wire twisting motor 7b in the normal direction to rotation of the same in the reverse direction. Additionally, in response to an output signal from the return position detecting sensor 38, the controlling apparatus stops rotation of the twist driving motor 7b.