Patent ID: 7334752

Claim:
A recording tape cartridge comprising: a case that houses a reel onto which a recording tape is wound, the case comprising an upper case including a top plate and a lower case including a bottom plate; lock members that are disposed, so as to be slidable in a radial direction of the reel, in an attachment portion formed on an inner surface of the top plate, the lock members being movable between a rise/fall lock position, at which the lock members are intervened between an upper surface of the reel and the top plate to prevent movement in an axial direction of the reel, and a rise/fall allowance position, at which the lock members are retracted from between the upper surface of the reel and the top plate to allow movement in the axial direction of the reel; and projecting portions that are formed on the inner surface of the top plate and project towards the lock members so that the lock members do not fall out of the attachment portion at least when the case is assembled.