| 摘要 |
A chuck for a machine tool is disclosed which comprises a cylindrical scroll board with a scroll groove being formed on one end surface thereof and having three radial slots formed therethrough at equi-angular intervals, three slider blocks radially movably received within the radial slots and each provided on the under surface with a number of arcuate grooves so as to be in communication with the scroll groove and on the radially inner end with an engaging element, a cup-shaped cover board adapted to rotatively receive therein the scroll board and provided on the annular cover plate constituting the bottom thereof with three radial slots at equi-angular intervals, three claws radially movably received within the radial slots of the cover plate and each provided on the under surface with a number of arcuate projections so as to be in mesh with the scroll groove, and a manipulating member axially movably received within a bore formed in the scroll board centrally thereof and adapted to be moved by an actuating means, the manipulating member being formed with three engaging means adapted to cooperate with the engaging elements so as to move the slider blocks radially when it is actuated. |
