For relatively large-scale nonvolatile storage, the disk memory is the favored data processing peripheral device. The typical modern disk drive has a detachable medium of the type whose recorded information can be recalled upon reattaching the disk to the drive.
Such drives have the disk modules or cartridges attached and detached by lifting or removing a panel or cover at the top of the drive unit, thereby exposing the spindle which rotates the disks, and the transducer assembly which reads and writes data on the disk surfaces. Such top loading drive units make it possible for the operator to manually attach the disk module to the drive unit in a straightforward fashion.
However, there are disadvantages with top loading drive units. Many installations have a large number of such units, and the top loading feature precludes stacking one on the other. Furthermore, top loading designs have a pivoted cover which requires a substantial amount of space directly above to which the cover pivots when a module is being mounted or dismounted. Accordingly, there has been a long felt need, not wholly satisfied to date, for a disk memory drive unit which accepts modules through a port on a vertical surface of the unit.