A speed direction corrector determines whether a speed Vp corresponding to a manipulated variable Up generated by a position controller is larger than a target speed Vt set in a target speed setting register (Vp>Vt). If Vp≦Vt, the manipulated variable corresponding to the target speed Vt is corrected to the manipulated variable Up to produce a new manipulated variable Uf. If Vp>Vt, a manipulated variable corresponding to the target speed Vt is set to the new manipulated variable Uf as is. As above, in a deceleration section where Vp≦Vt, the manipulated variable of a position control is reflected in the manipulated variable of a speed control. Combined use of the speed control and the position control becomes possible without a need to execute a complicated process in which the manipulated variable is regulated at the time of switching from the speed control to the position control.