| 摘要 |
PURPOSE: To obtain a miniature polygon motor which can rotate stably and accurately at high speed through a dynamic pressure bearing. CONSTITUTION: A sleeve 6 having herringbone grooves in the inner circumference thereof is inserted into a through hole 7 of a shaft 5 being fitted in the center of a bracket 3 for bearing a stator 4 with a polygon mirror 14 being fitted to the constricted part 6a of the sleeve 6. A bush rod 11 is fitted in the through hole 7 of the sleeve 6 at the upper part thereof and a thrust plate 12 is interposed between the push rod 11 and the shaft 5. The polygon mirror 14 is pressed against the sleeve 6 side by means of a clamp member 15 secured to the bush rod 11. The sleeve 6 is secured, at the enlarged part 6b thereof, to a rotor 8. An air vent is made in the through hole 7 of the sleeve 6 in order to discharge the air in the through hole 7 to the outside. This structure realizes a high speed miniature polygon motor producing a stabilized rotation. |
