Abstract: A protective cartridge for a data information disk having a disk containing case and a door moveable on said case between a closed position covering the disk and an open position for exposing the disk during a read operation. The door is supported on a subassembly comprising a slider, a support rod upon which said slider is mounted, and a biasing spring for urging the slider toward a door closing position. The subassembly is mountable as a unit with easy snap action engagement into said case.

Abstract: A rewritable optical disk is protectively enclosed in a cartridge having a base and having a hinged cover which is swingable to an open position permitting removal of the disk from the cartridge. A door with shutters is slidable on the cartridge between open and closed positions relative to access apertures formed in the cover and the base. The shutter for the access aperture in the cover is hinged relative to the remainder of the sliding door to enable that shutter to swing as the cover is opened and closed. The cover carries an axially and radially floatable hub which co-acts with the optical disk and the spindle of the disk drive to establish a precisely concentric relation between the disk and the spindle.