| 摘要 |
PROBLEM TO BE SOLVED: To obtain a rotary body without causing any imbalance and without deteriorating plane tilt characteristics by mirror-finishing a blank fixing a rotary shaft to a blank of a polygon mirror which is not mirror-finished yet, and then mirror-finishing the blank, thereby unnecessitating a highly precise machining. SOLUTION: As for the rotary body 42, after highly accurately machining the inner peripheral surface (a radial bearing surface as a fitting margin for a fixed shaft 35) of a rotary sleeve 31, the rotary sleeve 31 made of ceramics is fixed on the aluminum alloy blank for the polygon mirror 33 which is not mirror-finished yet. After forming a ring-like groove 46 in the upper surface of the blank, the inner peripheral surface 46a of the groove 46 is shaved so as to correct the imbalance of the rotary body 42. Next, the blank is mirror- finished to the mirror parts 33a and 33b so as to be parallel to the axial direction of the radial bearing surface of the rotary sleeve 31. Thereafter, a flange 32 and a rotary part 34 are fixed on the polygon mirror 33, and the rotary sleeve 31 is fitted on the fixed shaft 35, and then, the rotary body 42 is mounted on the fixed shaft 35. |
