| 摘要 |
PROBLEM TO BE SOLVED: To provide a device in a tool retention assembly suitable for high- speed operation having a small mass in a movable part. SOLUTION: This device in the tool retention assembly for moving a turnable shaft 1 in the axial direction includes a means disposed in a first end part 4, for executing operation during a turn of the shaft 1; an electric motor 3 for the turn; and one or more bearings 5, 6. The bearings 5, 6 radially support the shaft 1 and allow the movement of the shaft 1 in the axial direction. The shaft 1 has a free second end part 7. The device is provided with an electromagnetic means affecting the second end part 7 and attracting the shaft 1 to the axial direction from the first end part 4 to the second end part 7, against influence of pressure applied to the second end part 7 to the opposite axial direction; and a means 15 controlling the electromagnetic means to move the shaft 1 in the axial direction during the turn of the shaft 1. |
