Patent ID: 6991238

Claim:
A locking drill chuck comprising: a chuck body, a plurality of jaws, a nut, a nut jacket, a front sleeve, and a rear sleeve, wherein the chuck body has an axial hole at a rear end for engaging with a driving shaft, and the rear sleeve close fits with the outer circumference of the rear end of the chuck body, the jaws are separately fitted in a plurality of corresponding inclined holes equally departed away from each other in the chuck body, the nut engages with the jaws, the locking drill chuck further comprises (i) a locking sleeve provided between the front sleeve and the rear sleeve and (ii) a locking assembly provided between the nut and a stop plane of the chuck body, the locking assembly comprising a locking cap, a plurality of rolling members, and a locking plate, wherein the locking plate has a plurality of helical grooves with helix angle in an end plane thereof, the rolling members being received in the helical grooves, the locking cap has resilient tabs securing the locking plate together with the plurality of rolling members, and the locking sleeve securely connects to the locking plate.