Electrophotographic printing apparatus

An electrophotographic printing apparatus comprising:

• a photosensitive drum having a photoconductive layer on its surface;
• a primary charger for uniformly charging the surface of the photosensitive drum;
• a developing agent tank for containing powder developing
• a container for containing said developing agent tank;
• a developing means for supplying the powder developing agent supplied from the developing agent tank to the surface of the photosensitive drum;
• a cleaner for removing the powder developing agent from the surface of the photosensitive drum;
• an image-forming cartridge containing said photosensitive drum, said primary charger, said developing means, said container, and said cleaner;
• and
• a print head for forming an electrostatic latent image on the photosensitive drum;
• wherein a visible image using the powder developing agent corresponding to the electrostatic latent image formed on the photosensitive drum is formed, and the visible image is transferred to the surface of a printing paper to achieve printing;
• said apparatus further comprising:
• a frame mounted in a main body of said apparatus and having an opening which faces upward;
• and
• and openable lid mounted on said frame, covering said opening of said frame, and having a window;
• said print head being fixed on an inside surface of said lid and placed at a predetermined position with respect to said photosensitive drum when said lid is closed;
• said image-forming cartridge being mountable to said frame and removable from said frame only when said lid is opened;
• and
• said developing agent tank being mountable into said container of said cartridge and removable from said container of said cartridge through said window of said lid when said lid is closed.