| 摘要 |
PURPOSE:To reduce a vibration generated at the time of a positioning operation without increasing an exclusive area on the base by constituting so that positioning devices placed on the same place in the circumferential direction do not take charge of each adjacent magnetic disk group. CONSTITUTION:Plural positioning devices 2A1, 2A2, 2B1 and 2B2 which can be operated at a high acceleration are provided by two pieces each on a position which divides the circumference of a magnetic disk 1 into two equal parts. Also, plural magnetic disks 1 are divided into groups of the number of the positioning devices, and the positioning devices provided on said two places are assigned successively and alternately to the magnetic disks of each group. That is to say, the positioning device 2A1, the positioning device 2B1, the positioning device 2A2 placed on the right in the figure, and the positioning device 2B2 are assigned to the first magnetic disk group A, the second magnetic disk group B, the third magnetic disk group C, and the fourth magnetic disk group D, respectively. Accordingly, even in case when the positioning devices 2A1, 2A2 are operated at the same time, generation of a vibration can be suppressed. |
