| 摘要 |
<p>A shock-resistant drill chunk of hand tightening type is disclosed, which comprises a rear cap (1), a body (2), a thrust ring (3), a ball supporting ring (4), balls (5), a threaded ring (6), clamping jaws (7), a front cap (8), and an end cap (9). The ball supporting ring (4) is secured in body adjacent to the thrust ring (3), and 4~24 cylindrical through-holes (42) are arranged at the end face of the ball supporting ring (4), a ball (5) can spin freely in each cylindrical through-holes (42). The threaded ring (6) located in the second middle groove (24) of the body (2) has a sloping ball-race surface (61) facing the ball (5). During the end phase of the clamping process, the balls (5) move radially along the sloping ball-race surface (61) and abut against an inner wall of the cylindrical through-holes (42), so that a frictional force is produced between the balls (5) and the inner wall of the cylindrical through-holes (42) to prevent the ball (5) from rotating. Therefore the reverse rotation of the threaded ring is suppressed and the loosening of the tool under big shock is prevented.</p> |
