| 摘要 |
PROBLEM TO BE SOLVED: To make small a contact resistance even when a disk is in contact with the internal surface of cartridge and prevent generation of damage of disk and generation of dust within the disc cartridge. SOLUTION: The internal wall surfaces b of upper half 20 or lower half 22 of a cartridge corresponding to the surface of external circumference part a of disk or disk external. circumference part a are processed to become rough. The rough surface process of the internal wall surface b is conducted within 10 mm from the outer most circumference of the internal side of the annular frames 44, 46 corresponding to the disk external circumference part a. Any one of the surface opposed to a disk 10 of the internal circumference rib 40 in the side with which a recording disk 10 is pushed by a drive apparatus spindle to be in contact and the internal circumference surface of disk to be placed in contact with the rib 40 is processed to become rough and thereby generation of friction powder due to the contact between the rib 40 and disk 10 can be prevented. Moreover, the surface of the flange 52 of hub 18 opposed to the cartridge or the internal surface of cartridge opposed to the flange 52 is also processed to become rough. |
