Patent ID: 7581907

Claim:
A clamping structure for a handled tool, mounted to a driving spindle driven by a power source and comprising: a chuck body connected at its rear end with the driving spindle, having an accommodating space therein for clamping the tool handle, and having a plurality of guiding holes provided equally on a cone coaxial of the chuck body; a plurality of grippers connected with the chuck body, mounted in the guiding holes of the chuck body, and having the rear end with partial thread and the front end used for clamping the tool handle; a driving member mounted around the chuck body and having inner thread for mating with the partial thread of the gripper; and a control outer sleeve, characterized in that further comprising: a center gear fixedly mounted to the chuck body; an inner gear ring mounted coaxially with the chuck body, connected with the control outer sleeve, and having inner gear teeth thereon; and at least one pinion mounted to the driving member through a pin shaft and engaging with the inner gear ring and the center gear, respectively.