Abstract: A disk drive array system includes a plurality of disk drives. Each disk drive includes a period detector for monitoring the period of a common external synchronizing signal. When the period detector determines the existence of an irregularity in the external synchronizing signal, an internal synchronizing signal, generated by an internal generator, is used for controlling the rotation of each of the disks so as to continue the operation of the disks.

Abstract: A magnetic disk apparatus comprises a magnetic disk for recording information thereon; a power supply; an electric motor for rotating the magnetic disk by means of electric power which is supplied from the power supply; a floating type magnetic head for recording/reproducing the information onto/from the magnetic disk; and a carriage for moving and positioning the magnetic head on the magnetic disk by means of electric power supplied from the power supply, wherein when the rotation of the magnetic disk is started, the magnetic head rises from a predetermined CSS position on the magnetic disk, and when the rotation of the magnetic disk is stopped, the magnetic head comes to rest at the CSS position.

Abstract: A magnetic disc device includes a moisture removing mechanism within an enclosure of the device. The mechanism employs a reversible desiccating agent which is capable of not only absorbing moisture but also discharging moisture depending on the surrounding conditions. The reversible desiccating agent cyclically absorbs and discharges moisture in response to a change in temperature and a change in humidity due to the intrusion of the moisture from outside the enclosure. The moisture removing mechanism can be used for a long period of time with a small amount of desiccating agent. Thus, it is possible to make the moisture removing mechanism small and to provide it with long life.