To enable a servo motor to rotate at a high speed and to perform high-precision rotary positioning by varying the rotating speed of a handle.

When an operator rotates the handle 3, a manual pulse generator 5 generates a pulse signal according to the rotating speed of the handle 3 and a pulse conversion part 7 amplifies the signal by a pulse magnification to rotate the servo motor 21. At this time, a comparison part 11 compares the rotating speed of the handle 3 detected by a pulse speed detection part 9 with a previously set reference value and when the rotating speed of the handle 3 exceeds the reference value, a pulse magnification command part 13 increases the pulse magnification to increase the rotating speed of the servo motor 21, but when the rotating speed of the handle 3 is less than the reference value, the pulse magnification command part 13 decreases the pulse magnification to lower the rotating speed of the servo motor 21.