Patent ID: 7360734

Claim:
A recording tape cartridge comprising: a case; a reel rotatably accommodated in the case, a recording tape being wound around the reel, the reel having a hub and an engaging portion formed at a floor wall of the hub; a braking member provided so as to face the engaging portion and so as to be movable along an axial direction of the hub, the braking member being able to restrict rotation of the reel by engaging with the engaging portion, and being able to permit the rotation of the reel by canceling a state of engagement with the engaging portion; a part mounting portion formed at the case; a locking member mounted to the part mounting portion so as to be movable in a radial direction of the reel, the locking member restricting axial direction movement of the reel by being interposed between the reel and the case, and permitting movement of the reel by being pushed by the braking member and moving away from the reel; and an urging element urging the locking member in the radial direction of the reel, and interposed between the reel and the case, and restricting the axial direction movement of the reel, wherein convex and concave portions are provided at sliding surfaces of the locking member and the case.