Recording tape cartridge

A recording tape cartridge which can be loaded at a drive device, the recording tape cartridge comprising:

• a case;
• a reel accommodated in the case, the reel including a tubular hub around which a recording tape is wound at an outer peripheral portion thereof, and an engaging portion provided within the hub;
• a locking member supported to be non-rotatable with respect to the case and disposed within the hub, the locking member being capable of attaining a rotation-locking position, for engaging with the engaging portion and filling a gap between the case and the reel in an axial direction of the reel, and a rotation-enabling position, for releasing the state of engagement with the engaging portion and withdrawing the locking member from the gap;
• a switching member disposed in the case, which retains the locking member at the rotation-locking position at times of non-use of the recording tape, moves the locking member to the rotation-enabling position when operated in a predetermined direction by the drive device, and moves the locking member to the rotation-locking position when operated in a direction opposite to the predetermined direction by the drive device;
• and
• a positive motion cam mechanism which comprises a cam portion, which is disposed at either one of the locking member and the switching member and is inclined with respect to the axial direction of the reel, and a contact member, which is disposed at the other of the locking member and the operable member and slidably contacts the cam portion, and the positive motion cam mechanism causes the locking member to move between the rotation-locking position and the rotation-enabling position in accordance with reciprocating movement of the switching member in the axial direction of the reel.

A locking mechanism for locking rotation and enabling rotation of a reel in a recording tape cartridge which can be loaded at a drive device and which includes a case and the reel, the reel being rotatably accommodated in the case, including a hub around which recording tape is wound at an outer peripheral portion thereof, and an engaging portion provided within the hub, the locking mechanism comprising:

• a locking member supported to be non-rotatable with respect to the case and disposed within the hub, the locking member being capable of attaining a rotation-locking position, for engaging with the engaging portion and locking rotation of the reel, and a rotation-enabling position, for releasing the engagement with the engaging portion and enabling rotation of the reel;
• a switching member disposed in the case, which retains the locking member at the rotation-locking position at times of non-use of the recording tape, moves the locking member to the rotation-enabling position when operated in a predetermined direction by the drive device, and moves the locking member to the rotation-locking position when operated in a direction opposite to the predetermined direction by the drive device;
• and
• a positive motion cam mechanism which comprises a cam portion, which is disposed at either one of the locking member and the switching member and is inclined with respect to the axial direction of the reel, and a contact member, which is disposed at the other of the locking member and the operable member and slidably contacts the cam portion, and the positive motion cam mechanism causes the locking member to move between the rotation-locking position and the rotation-enabling position in accordance with reciprocating movement of the switching member in the axial direction of the reel.