Patent attributes
A self-locking drill chuck device includes a body, a nut, jaws, a front sleeve, a rear sleeve, a nut jacket and a rolling member. Three jaws are respectively and operatively inserted into three angled bores uniformly distributed around the body, the threads of the nut engages with that of the jaws to form a thread driving mechanism. A ratchet wheel is fixedly mounted at a rear portion of the body, a disk spring is provided between the rolling member and a load carrying shoulder of the body, the front portion of the body has key slots and an annular connecting groove, the rear end of the nut jacket has a plurality of driving grooves and keys on which a locking elastic element and a driving elastic element are respectively fixed. The drill chuck has a simple structure, convenience of operation and high working stability and reliability of self-locking capacity.