Patent ID: 7243361

Claim:
A disk cartridge, comprising: a cartridge body including a lower shell having formed therein a first opening for write and/or read and an upper shell butt-joined to the lower shell; a rotation wheel housed rotatably in the cartridge body and which houses a disk and has formed therein a second opening corresponding to the first opening and through which the housed disk is exposed to outside; and a shutter mechanism provided between the lower shell and rotation wheel and which operates with the rotation of the rotation wheel to uncover the first and second openings when the latter are coincide with each other; and a locking member including a shaft portion installed pivotably to any one of the shells, a locking portion engaged in an engagement concavity in the rotation wheel to lock the rotation wheel in a position where the shutter mechanism covers the first opening, and an unlocking portion which cancels the engagement of the locking portion in the engagement concavity, the cartridge body having formed therein an insertion guide recess open at the side of the cartridge body, at which the latter is first inserted into a disk recorder and/or player; and the locking portion having an unlocking piece which is opposite to the insertion guide recess.