Abstract: A disk cartridge (4) formed of a pair of cartridge halves (1) and (2) in which a recording and reproducing disk (5) is rotatably accommodated is characterized in that a plurality of supporting members (25), (26) or (35), (36) made of silicone rubber are fixed to the inner surfaces of the cartridge halves (1) and (2) so as to correspond to non-signal recorded portions on the inner and outer peripheries of the disk, wherein upon non-use of the disk, it is supported by the supporting members on any one of the cartridge halves.

Abstract: In a disk cartridge, wherein a disk is accommodated in a cartridge, a first rack and a second rack are so provided as to be movable along respective sides of the cartridge, which are perpendicular to each other, a transmission mechanism links the first rack with the second rack, a shutter is secured to the second rack, and at least recording head or reproducing head insertion openings of the cartridge are opened and closed by the shutter as the second rack is moved by the first rack, the transmission mechanism comprises an eccentric pin provided on a first pinion meshed with the first rack, a second pinion meshed with a third rack fixed to the cartridge and the second rack, and a rod connecting the eccentric pin with the shaft of the second pinion, so that the stroke of the shutter can be made much larger without changing the stroke of the first rack or the size of the cartridge.

Abstract: In a tape cassette in which a guide pin, a guide roller and a bracket guide within the housing are engaged, in succession, by tape extending from a coil thereof rotatable within the housing with the tape engaging the guide pin and guide roller at sides thereof facing away from the coil, entwining of the tape with the guide pin due to loosening of the outer turns of the tape coil is prevented by providing an L-shaped member extending between the bracket guide and the guide pin at the side of the guide roller facing toward the coil with an acute angle included between angularly related arms of the L-shaped member opening toward the guide roller.