| 摘要 |
PURPOSE:To prevent oil from staining a rotation mirror, degrading the precision of a revolving shaft, and shortening its life by using a foam resin as a fixing friction member of a rotating mirror fixing mechanism. CONSTITUTION:When a scanning optical device is moved, a moving plate 12 is moved in the direction of an arrow C with a stopper plate 10 pushed in downward in the direction of an arrow B. The stopper plate 10 which tries restoration in the direction of an arrow A by the pressing force of a compres sion spring 11 is brought into contact with the moving plate 12 and is stopped, and a stopper shaft 9 is moved downward by a distance (b) from the normal state, and therefore, a cushion 13 is deformed by an extent corresponding to a distance (b-a) to compress the head of an air bearing 2, and a polygon mirror 6 is fixed. The cushion 13 compresses the air bearing 2 by an unfoaming layer which has a satisfactory wear resistance and several 100mum thickness. Thus, the friction member has a high wear resistance and has a sufficient elasticity without oil. Thus, ooze of oil and the occurrence of dust are prevented. |
