| 摘要 |
A chuck apparatus in which an internally provided nut member (2) is rotated by rotating a sleeve (1) so that claws (3) threadedly engaged with the nut member (2) by the rotation of the nut member (2) are advanced/retracted for narrowing/expanding a diameter defined therewith and pressingly fastening/releasing a tool (4). A rotary member (7) is provided to face the nut member (2). A set of an even number of rolling members are provided in a recess portion (7a) formed in the rotary member (7). The rolling members (5) are provided under the condition that the rolling members (5) are in contact with the nut member (2) and a rolling member receiving portion (6) between a predetermined surface of the nut member (2) and the rolling member receiving portion (6) provided to face the predetermined surface of the nut member (2). The predetermined surface is formed into a slant surface (2a); and the rolling members (5) are rollingly rising along the slant surface (2a) by rotating the rotary member (7) to thereby press the nut member (2) forwardly. <MATH> |
