| 摘要 |
PURPOSE: To prevent the fitting position of a weight from being restricted when the driving part of a rotary polygon mirror is an inner rotor type motor. CONSTITUTION: The motor M of the rotary polygon mirror 1 is an inner rotor type motor which has its rotor magnet arranged inside the stator coil 7. Balance grooves 8 and 9 are formed in the top surface of the rotary polygon mirror 1 and the reverse surface of the rotor magnet 5, and weights 8a and 9a are fitted thereto to completely eliminate the dynamic imbalance between the rotary polygon mirror 1 axially and radially, thereby preventing the rotary polygon mirror 1 from vibrating during its rotation. A motor substrate 6, the yoke 7a of the stator coil 7, and a base 2 which supports them have through holes and the weight 9a is fitted to the rotor magnet 5 through the through holes 10. |
