| 摘要 |
<p>A master servo motor (16) and a slave servo motor (21) that synchronously drive for rotation a master main spindle Cm provided with a center (14) that supports one end of a work piece W and a slave main spindle Cs provided with a center (18) that supports the other end of the work piece are included. Before grinding, a slip detection cycle that detects a limit current value (A1) for the servo motors, at which the work piece and the centers slip, is executed and, during grinding, a grinding condition is changed to prevent a slip between the work piece and the centers in advance at the time when any one of current values of the servo motors has reached a slip threshold value (A2) set on the basis of the limit current value.</p> |
