Patent ID: 6901602

Claim:
In a disc recording/reproducing apparatus comprising: an external case for accommodating therein a main body of the disc recording/reproducing apparatus; a front panel mounted on the front of the external case, wherein the front panel has a cartridge port for inserting a disc cartridge into the external case; wherein the disc cartridge comprises: a cartridge case its which a disc accommodating chamber is formed between an upper shell and an intermediate shell or between the intermediate shell and a lower shell by overlaying the upper shell, the intermediate shell and the lower shell, white the intermediate shell is supported rotatably by the upper shell and the lower shell; a disc-like recording medium which is accommodated rotatably in the disc accommodating chamber while part of the disc-like recording medium is exposed through an opening portion provided in the intermediate shell, the lower shell or the upper shell; and a pair of shutter members mounted on the intermediate shell, capable of opening/closing the opening portion; and a shutter opening/closing means for rotating the intermediate shell up to a predetermined position by engaging with a driven portion, which is provide on an external peripheral face of the intermediate shell and faces an operating window formed on at least one of the upper shell and the lower shell.