| 摘要 |
<p>A main spindle positioning method which makes the most of deceleration of a spindle motor and speeds up a spindle positioning operation. It is assumed that the spindle motor is running under speed control. In response to a command for a stop at a given position, the spindle motor is decelerated to a speed N below a maximum rotating speed N1 determining a constant torque region on the basis of the speed control (Step S1), and the speed control is switched to a position control at the position at which the speed N is reached. At this time, a value which takes into consideration the present position at one rotating position of the spindle and a target stop position as an initial position error are set to an error counter (Steps S5 to S11). Thereafter, a position feedback quantity Pf from a position sensor is received by the error counter so as to execute linear acceleration/deceleration control to a final stop position (Step S12) and a speed command Vcmd is determined (Step S13), and a speed loop processing follows.</p> |
