| 摘要 |
PURPOSE:To improve the perpendicularity and parallelism of a polygon rotor by interposing and arranging a slide member between a rotary body and a support body and arranging exposingly a stator coil which is provided corresponding to a magnet to the outside of an enclosed case in an atmosphere open state. CONSTITUTION:The slide member 10 made of a ceramic material where a groove 11 for dynamic pressure generation, i.e. spiral groove is formed is interposed and arranged between the rotary body 3 and support body 4, and a hollow chamber 20 wherein the polygon rotor can be put is enclosed by the support body 4, a cover body 12 fitted thereupon, and a seal material 23 such as an O ring. In this case, atmospheric heat radiation structure wherein the stator coil 6 is provided outside the cover body 12 fitted on the support body 4 is employed instead of providing the stator coil 6 outside the support body 4 constituting the enclosed case. Consequently, even if the rotary body is put in operation in the enclosed structure, heat radiation is excellent and the perpendicularity and parallelism of the polygon mirror are improved greatly. |
