| 摘要 |
PURPOSE:To prevent the rotary polygon mirror which is used for a light deflection device from deteriorating in reflection accuracy owing to thermal expansion while rotating at a high speed. CONSTITUTION:The lower part of the core hole 3 of the polygon mirror is fitted onto the lower fitting part 6 of a rotary shaft 4 which has a small- diameter fitting part 5, an intermediate-diameter fitting part 6, and a large- diameter bearing seat 8 from its upper end part and after the fitting shaft part 14 of a pressure member 11 consisting of a flange part 13 and a fitting part 14 is fitted in the upper part of the core hole 3 of the polygon mirror 1, a screw 16 for fixation is inserted into plural through holes 15 penetrating the pressure member 11 from the top surface to the reverse surface of the fitting shaft part 14; and the tip part of the screw for fixation is screwed in a screw hole 10 formed in the top surface of the lower fitting part 6 and clamped to clamp and fix the polygon mirror 1 between the receiving seat 8 and the flange part 13 of the pressure member 11. |
