| 摘要 |
PROBLEM TO BE SOLVED: To effectively prevent the separation of a weight added for balancing without cutting a groove on a polygon mirror. SOLUTION: In the polygon scanner motor 1 in which the fitting hole 31 of the polygon mirror 3 provided with a reflecting surface 32 for optical scanning at the side face is inserted and fixed in the projecting part 6 of a rotor 26, a weight member 9 for balancing is mounted in a required region in an annular depression 8 formed at the inner peripheral surface side of the fitting hole 31 by forming an annular depression step part on the outer peripheral surface of the upper end of the projecting part 6, thus the weight member 9 is made not to be peeled and flown with centrifugal force during the rotation. |
