| 摘要 |
PURPOSE:To make compact a clamping device and to improve the clamping function by energizing an electromagnetic chuck for holding a tool through the electric energy produced from a small high speed generator provided on the spindle. CONSTITUTION:Upon starting of a spindle 1 through a high speed motor HM at the time point t2, necessary holding force F' for the tool holder TH is produced at the time t3 when the rotation is approximately 500rpm. Upon increase of the rotation at the time t3' when it is higher than the intermediate speed, the clamping force of an electromagnetic chuck EC will increase to the sufficient level F1 correspondable with the high speed rotation and stabilized. At the time t4, the rotation of the spindle 1 will increase to the high speed rotation Nmax and stabilized. While when decreasing the speed at the time t5, the clamping force F1 is held untill the time t6 under the intermediate speed region and at the stopping time t7, the clamping force of only the ball 11 is produced. At the time t8, it is replaced with next tool holder through ATC operation or manual operation. |
