In a tape
cartridge which turnably holds within a housing a single tape reel on which a length of tape is wound, the tape reel consisting of an upper
flange, a lower
flange, and a hub which is open at top and is closed at the bottom, the hub having a
metal disk in the center of the outer bottom surface and teeth formed around the outer periphery of the
metal disk for engagement with a
drive shaft of a recorder, the underside of the hub having throughholes for engagement with a
brake release plate, the hub having teeth formed on the inner bottom surface to engage a
brake lock, the
brake release plate consisting of a main plate disposed between the brake lock and the inner surface of the hub and a plurality of legs adapted to fit in the throughholes in the bottom of the hub, the brake lock having brake teeth formed on the periphery of its underside and a contact area in the center for engagement with the brake release plate, the teeth of the hub and the brake teeth of the brake lock being in mesh to prevent unwanted turning of the tape reel, and further including a spring member provided between the brake lock and an upper casing of the housing to urge the brake lock in the braking position:the invention forms a short
toe on the outer end of each leg of the brake release plate so as to prevent the leg from coming off, out of engagement with, a corresponding hole of the hub; provides a reinforcing structure between the center of main plate and the legs of the brake release plate; precludes the possibility of a once-incorporated brake release plate coming off from the hub during the course of assembling; and ensures positive
release action of the brake release plate.