Abstract: A disc cartridge housing a driving rotating unit and adapted to be loaded along with the driving rotating unit on a recording and/or reproducing apparatus. A shutter mechanism for opening/closing an opening provided in a main cartridge body portion includes two shutter members movable along the major surface of the main cartridge body portion. An area in which the first shutter member and the second shutter member are moved is delimited by first and second wall sections arranged facing each other. The first and second shutter members are intruded into a spacing defined between the first and second wall sections. The first and second wall sections are arranged in the portions of the main cartridge body portion facing the major surface of the disc-shaped recording medium so that the wall sections face each other with a pre-set separation in-between. The main cartridge body portion is formed with first and second openings facing the first and second wall sections.

Abstract: A disc cartridge housing a disc-shaped recording medium in its main cartridge body portion is disclosed. The disc cartridge includes the main cartridge body portion having a circular medium housing section rotationally housing the disc-shaped recording medium and an opening for exposing at least a portion of the disc-shaped recording medium to outside, and first and second shutter members rotated along the major surface of the main cartridge body portion to open/close at least the above opening. The first shutter member is supported for rotation along the circular medium housing section provided on the main cartridge body portion. The second shutter member is supported by the main cartridge body portion for rotation in conjunction with the rotation of the first shutter member. When the first shutter member is moved to a first position overlying the opening, the second shutter member is intimately contacted with a lateral side of the first shutter member to overlie the opening.

Abstract: The invention is associated with a bicycle and a bicycle folding method which allow a rider to easily and securely fold and unfold the bicycle. A bicycle comprises: a front wheel and a rear wheel; a saddle on which a rider rides; a pair of pedals to which the rider imparts drive force; a first frame for holding the front wheel in a rotative manner; a handle for changing the direction of the front wheel; a second frame for holding the rear wheel in a rotative manner; and a linking portion for linking a linking member of the first frame with a linking member of the second frame, wherein the first frame and the second frame are brought close to each other by the rider's lifting the linking portion with the front wheel and the rear wheel kept in contact with the ground, thereby folding up the bicycle with the front wheel and the rear wheel overlapping each other in at least one portion thereof.

Abstract: A disc cartridge housing a disc-shaped recording medium in a main cartridge body portion is disclosed. The disc cartridge includes a main cartridge body portion having a circular medium housing section for rotationally housing a disc-shaped recording medium, a recording and/or reproducing opening for exposing at least a portion of the disc-shaped recording medium to outside and a driving opening for allowing intrusion of a rotating driving unit adapted for rotationally driving the disc-shaped recording medium. The disc cartridge also includes a shutter mechanism having a shutter member rotated along the major surface of the main cartridge body unit in a region provided with the medium housing section to open/close the recording and/or reproducing opening and a plurality of cartridge supporting portions at plural corner regions of larger area outside a region provided with the medium housing section of the main cartridge body unit.