Recording tape cartridge

A tape drive for carrying out at least one of reading and writing of data at an insertable and removable tape cartridge, the tape drive comprising:

• (A) an opening member capable of operatively engaging with the tape cartridge at a time of insertion of the cartridge;
• and
• (B) an engaging member capable of operatively engaging with the tape cartridge at the cartridge insertion time, wherein
• (C) the tape cartridge includes:
• (a) a case;
• (b) a tape access opening provided at one side relative to a center line of the case, the center line extending in a direction of the insertion of the cartridge;
• (c) a covering member which is reciprocally moveable between a closed position for closing the tape access opening and an open position for opening the tape access opening;
• (d) an operation portion which cooperates with the opening member of the tape drive at the cartridge insertion time and moves the covering member in the direction of the open position;
• and (e) an engagement portion provided at the other side relative to the centre line of the case, which cooperates with the engaging member of the tape drive and is capable of implementing a counterbalancing function with respect to movement of the covering member in the direction of the closed position.