MANDRINO AUTOCENTRANTE,IN PARTICOLARE PER UTENSILI ELETTRICI PORTATILI

摘要

The invention is directed to a chuck for grasping a tool such as a drill bit or the like and adapted to be tightened with the aid of a chuck key. The chuck includes a hollow body defining a longitudinal axis and having a front end for receiving the tool therein. A plurality of elongated jaws are movably mounted in the hollow body. A sleeve is rotatably mounted on the body and threadably engages the jaws to move the jaws in the body to clamp and release the tool whereby substantial radial forces are transmitted to the body by the jaws when the jaws are tightened on the tool. The sleeve extends in the direction of the longitudinal axis of the hollow body to surround the hollow body at the region of the jaws for supporting the body against the radial forces. A gear is provided for coacting with the chuck key to actuate the sleeve to move the jaws for tightening the jaws on the tool.