Patent ID: 6031675
Filing Date: 2000-02-29
Classification: G11B

Abstract:
A recording medium device for use in a recording/reproducing apparatus comprising:a cartridge body accommodating a recording medium on which information signals are recorded, said cartridge body having a cover member and a base plate joined to each other, said member including a top plate which has an inner surface portion facing said base plate;an erroneous recording prevention member attached to the cartridge body and including a detection member at a base end portion side thereof detected by detection means of the recording/reproducing apparatus, said erroneous recording prevention member being movable between a first position, where the detection member is detected by the detection means, and a second position, where the detection member is not detected by the detection means, wherein the erroneous recording prevention member is attached to the cartridge body so that the detection member can be moved between the first position and the second position by retaining the cartridge body by a holding portion provided at the base end portion side and inserting an insertion portion provided at a front end side of the holding portion from the external side toward the internal side of the cartridge body into an engagement recessed portion of the cartridge body, andpositioning means for securely retaining said erroneous recording prevention member in its said first and second positions wherein said positioning means includes a projection member extending from said insertion portion which is engaged with first and second recessed portions integrally formed in the facing inner surface portion of said top plate of said cover member when said erroneous recording prevention member is moved between its said first and second positions such that said erroneous recording prevention member remains in substantially the same horizontal and vertical planes as two of the outer surfaces of said cartridge body when said erroneous recording prevention member is moved between its said first and second positions and wherein said projection member extends upwardly from a projection plane and substantially parallel to the horizontal plane of one of said outer surfaces and said first and second recessed portions are formed in a plane substantially parallel to the projection plane of said projection member.