Cartridge having casing with shutter movable to receive discs therein

Claim 1

A disc cartridge comprising: a casing comprising an upper casing member and a lower casing member joined together to define a space therein, said casing being formed with at least one pickup inserting hole; a disc mounted in said casing so as to be rotatably movable therein; a shutter which is substantially U-shaped an comprises an upper shutter plate, a lower shutter plate and a slider, said upper shutter plate, said lower shutter plate, and said slider each having respective mating projections and holes such that said upper shutter plate is connected to said slider and said lower shutter plate is connected to said slider; said shutter having a guide projecting which engages with a guide groove of said casing such that said shutter is slidably movable relative to said casing to cover and uncover said pickup hole; a wall of said casing having a portion thereof defining said pickup hole and, at said portion, being formed to be therein thinner than at its other portions and to be at a level substantially equal to or below the level of the plane of said disc, said guide groove being positioned on said portion of said wall; and wherein said slider of said shutter comprises a thin walled section at a level substantially equal to or below said level of said disc at a portion thereof positionally corresponding to said thinner portion of said wall casing when said shutter is moved to uncover said pickup inserting hole, said guide projection being provided on said thin-walled section.