| 摘要 |
PROBLEM TO BE SOLVED: To obtain an image forming apparatus that the earthquake resistance of a polygon motor is improved. SOLUTION: A brake arm 11 is rotatably at a shaft 12. A solenoid 14 and a brake member 10 are mounted at both the ends, and a rotary force in clockwise direction is applied by a spring 13. Accordingly, in the normal state that the solenoid 14 is not energized, the member 10 is brought into contact with the polygon mirror retainer 19 of a rotor by the tension of the spring 13 and pressed. At the time of energizing the solenoid 14, the solenoid 14 is operated, the arm 11 is rotated in the direction of an arrow A, and the brake is released. The braking is controlled in cooperation with the rotary drive of the mirror to rapidly stop the rotating operation at the time of no necessity of the rotating operation of a polygon mirror 8, and the rotor held in non-contact can be mechanically held. |
