Patent ID: 9744601
Date: 2017-08-29
CPC Classifications: B23B,Y10S,Y10T

Claim:
1. A drill chuck, comprising: a drill body having a plurality of inclined guiding holes distributed evenly along a circumferential direction; a plurality of clamping jaws arranged slidably in the inclined guiding holes respectively and having external thread segments; an outer socket rotatably fitted over the drill body; and a nut engaged with the clamping jaws and connected to the outer socket in a driving manner; further comprising: a locking mechanism located between a first thrust surface of the drill body and the nut and having a locking plate and locking balls, wherein an end face of the locking plate facing the nut is thereon provided with a plurality of slide grooves having a helix angle, the helix angle of the slide grooves is less than a friction angle between the locking balls and the locking plate, and the locking balls are movably arranged along the slide grooves; the locking mechanism further comprising an annular pad located between the locking balls and the nut and movably arranged along an axial direction of the drill body, and wherein an inner wall of the annular pad has at least one limit surface to prevent the annular pad from rotating around the drill body.