| 摘要 |
PURPOSE:To employ a constant structure for a center of rotation by providing bearing between a reflecting mirror and a support member, a receiving part which holds the bearing rotatably, and a traction member which draws the reflecting mirror toward the support member. CONSTITUTION:A hook 11a is provided to the center part of a plate type holder 11 fitted to the reflecting mirror 1 on the opposite side to the reflecting mirror, and spherical bearing receiving parts 11b and 11c made of holes are provided above and below it. Further, a V-groove type spherical bearing receiving part 9c and a conic recess type spherical bearing receiving part 9d are provided above and below it, and spherical bearings 13 and 14 are fitted partially in the respective receiving parts 9c and 9d, and 11b and 11c. Those bearings 13 and 14 are provided along an axis prolonged in parallel to the reflecting surface of the reflecting mirror 1 and constitutes a rotating shaft. |
