To surely keep the engagement with a cartridge and to stably load and move the cartridge to/from a cartridge chamber by constituting an engaging pawl so that it can be moved in two independent directions on a plane perpendicular to a cartridge loading direction.

When the cartridge 1 is inserted, the corner of the cartridge comes in contact with the guide part 7d of a feed table 7, and the whole is rotated around a feed screw 6 in a direction shown by an arrow G. At this time, a hook pawl 8b is simultaneously rotated, so that the relative position of a recessed part 1f and the hook pawl 8b is not changed even in the case the cartridge 1 is moved in any direction. Besides, when the cartridge 1 is moved upward, the hook pawl 8 is pressed by the corner of the cartridge 1, then, it is rotated in a direction shown by an arrow D once, thereafter, it is engaged with the recessed part 1f. That is, however the cartridge 1 is loaded, the guide part 7d always comes in contact with the outside wall of the cartridge 1, and the hook pawl 8b is made to follow the action of the cartridge 1, then, the hook pawl 8b is engaged with the recessed part 1f.