| 摘要 |
PURPOSE:To improve the workability by employing such structure as the movement of the for jaw is replacable with that having the spacer of different thickness thereby simplifying the adjustment of the chucking work in accordance to the diameter. CONSTITUTION:A top jaw 3d and a pair of spacers having required thickness are placed in a recess 16 in the longitudinal direction of a drive jaw 2c, where the top jaw 3d is positioned while moving by the thickness T of the spacer 19 to secure the top jaw 3d to the drive jaw 2c with required diameter. When selecting the spacer 19 having different thickness T and replacing dismountably the chucking in accordance to the diameter of the work is achieved resulting in the improvement of the workability. |
