An apparatus for holding a toolholder shank utilizing a rotatable cam to minimize kickback

Through the locking position and with a locking the locking rod of the positions and a back and forth to move (95) through the dismountable type fixing tool clamp of handle (45) and a device, the cam for using rotatable (150) such a lock rod (95) reciprocating moving, the cam of rotatable (150) by the preload spring (200), forming the (95) is fixed on the lock rod the locking position force; and support shaft (15) comprises a non-cylindrical cam column (160); when the lock rod (95) close to from the locking position with a locking the position, the cam column (160) is connected with the preload spring (200) is provided with a smallest repulsive force.