Patent ID: 6108298
Filing Date: 2000-08-22
Classification: G11B

Abstract:
A disc cartridge comprising:an upper plate having an inner side;a lower plate having an inner side facing said inner side of said upper plate;a center frame arranged between said inner sides of said upper plate and said lower plate so as to join said upper plate and lower plate to each other therethrough using fixing means; anda disc-shaped medium received in said center frame;said center frame being constituted by a member having a substantially square shape as viewed in plan, said center frame having a side surface and an inner peripheral surface which is formed so as to continuously surround said disc-shaped medium;said upper and lower plates being provided on four corners thereof with fixing bosses through which said upper and lower plates are joined to said center frame, respectively, said fixing bosses of said upper plate and those of said lower plate being arranged in a manner to be opposite to each other, said fixing bosses of said upper plate projecting from said inner side of said upper plate and said fixing bosses of said lower plate projecting from said inner side of said lower plate;said upper plate, said lower plate, and said center frame having substantially the same size when viewed in plan so that side surfaces of said upper plate, said lower plate and said center frame form a side surface of the disc cartridge;said center frame being formed on opposite surfaces thereof with fitting recesses in which said bosses are fitted, respectively;said center frame being formed on each of four corners thereof with a thin-wall portion having a reduced thickness of 50 to 80% based on a whole thickness of said center frame.