MAGNETIC DISK DRIVER

PURPOSE:To obtain precise labyrinth seal effect through simple working by arranging a fixed shaft at the center of a cylindrical protrudent part formed at a base plate, and forming clearance between the outer side face of the bearing of the fixed shaft and the inner side face of the cylindrical protrudent part. CONSTITUTION:The cylindrical protrudent part 11 is formed integrally with the base plate 12, and the fixed shaft 13 is arranged at its center. The fixed shaft 13 is provided with a bearing 15, and a hub 16 is fixed to its end. An annular rotor magnet 19 is arranged on the inner side face of the hub 16, and an armature 20 is arranged on the outer wall of the protrudent part 11 so as to be opposite to the magnet 19. The hub 16 is provided with a magnetic seal 21 to shut off substantially the tip end part of the bearing 15 from the storage space of magnetic disks 17a, 17b. In this constitution, the clearance (a) of prescribed length is formed between the side wall of the bearing 15 and the inner wall of the protrudent part 11. Thus, a labyrinth seal to shut off substantially the lower end part of the bearing 15 from the storage space of the magnetic disk can be formed.