Patent ID: 7440232

Claim:
A recording disk cartridge comprising: a plurality of flexible recording disk media integrally rotatably housed within a cartridge case, said recording disk media being fixed to respective center cores which are stacked one on another through a spacer, the cartridge case comprising: a lower plate for configuring a lower wall parallel to the plurality of the recording disk media; at least one inner plate that is stacked and fixed on the lower plate, and partitions the plurality of the recording disk media; and an upper plate that is stacked and fixed on said inner plate, and configures an upper wall of the cartridge case, wherein each spacer is provided with locking protrusions at upper and lower surfaces thereof, and wherein each center core is provided with locking holes for engagement with the locking protrusions of adjacent spacers, wherein said locking protrusions are arranged equidistantly along a circle having center which is a rotation axis of the spacer, and wherein said locking protrusions are arranged so as to produce alternately at an upper side and lower side of the spacer.