| 摘要 |
<p>A base of an arm having a driving projection (16) at its tip is rotatably supported on a turn table (11). The turn table is provided with a first guide part (18) and a second guide part (19), an outer edge part of the base of the arm and a first guide part are in contact with each other at a contact point (A), and a projection and a second guide part are in contact with each other at a contact point (B). While the arm rotates in a counterclockwise direction, the contact points are moved, and it is possible to prevent the center of the driving projection from largely deviating from a reference normal. Thus, even if a hub in which the position of the driving hole is shifted is mounted, the hub is not largely shifted in a rotation direction relative to a turn table. <IMAGE></p> |
