Abstract: A disc of a magnetic disc cartridge is braked while the cartridge is outside of a receptacle of a magnetic disc memory unit by a radially extending leaf spring mounted on a wall of the cartridge so it has a free end engaging an aperture in a drive platter. The drive platter has an aperture that is engaged by a drive post of a drive disc connected to the memory drive shaft while the cartridge is inserted in the receptacle. The leaf spring is positioned so that the free end thereof is lifted out of the aperture by a post fixedly mounted on the memory unit to release the brake member while the cartridge is in place in the receptacle.

Abstract: A container for a magnetic data recording disc includes a flat cassette shaped for insertion into a receptacle of disc memory of a data processing apparatus. A normally closed opening in a sidewall of the cassette provides access to the disc for recording and/or reading heads of the data processing apparatus. The cassette includes a pair of generally parallel walls that extend in a direction generally parallel to faces of the disc. One of the opposing walls includes an opening for enabling rotary drive means of the apparatus to be coupled to an annular hub of the disc. The opposed walls are rigid, but elastically deformable. In a free state, the opposed walls are outwardly convex. An internal projection extends from the center of the other opposed wall. The projection has an annular bearing surface facing the inside face of the other wall. The one opposing wall has an opening coaxial with the projection. The opening is surrounded by an annular bearing surface on the outside face of the one wall.