Patent ID: 7607769

Claim:
A refill unit comprising: a case having an opening formed in a front face thereof for inserting/extracting an ink cartridge and a holding portion communicated with the opening for housing the ink cartridge; a door being capable of moving between a closed position to close the opening and an opened position to open the opening; a locking member being capable of sliding between a protruded position, at which the locking member is protruded from the door, and a retracted position, at which the locking member is retracted toward the door, and adapted to engage with the case at an intermediate position between the protruded position and the retracted position to lock the door in the closed position, the locking member being capable of being displaced toward the retracted position to release the engagement; and an unlocking member turnably supported on the door and being capable of moving, when the door is in the closed position, between a neutral position, at which the unlocking member is inclined from the front face of the case, and a housed position, at which the unlocking member is substantially parallel with the front face of the case, the unlocking member being capable of being displaced from the neutral position to a fallen position to displace the locking member from the intermediate position to the retracted position.