Abstract: A rotary actuator utilizing a magnetically biased bearing. A magnetized rotor is held in close proximity to a ferromagnetic mount. The magnetic flux created by the magnetic rotor through the ferromagnetic mount creates a magnetic bias force on the rotor bearing surface. The rotary actuator with the magnetically biased bearing rotates a mounted mirror to direct a reading laser beam to act as a fine tracking actuator within an optical data storage system.

Abstract: A data storage apparatus includes an interchangeable sealed cartridge, enclosing magnetic disks, accessing magnetic head arm assemblies, a movable carriage to which the head arms are mounted, and a drive spindle on which the disks are seated. This portion of the storage apparatus is referred to as a data module. For accessing the heads to selected data tracks, coupling means are provided to engage the carriage and head arm assemblies with an external actuator, such as a linear D.C. motor or voice coil motor, disposed in a disk file housing. The file housing includes a drive motor coupled by pulley means, for example, to the enclosed spindle to provide rotary motion to the disks. This latter portion of the storage apparatus is referred to as the data module drive. The data module drive operates as a data storage apparatus when combined with one of many interchangeable data modules.