Electrophotographic printing device

Claim 1

An electrophotographic printing device comprising: a cartridge of a photosensitive unit; a printing mechanism for effecting a printing operation by electrifying a photosensitive member of said photosensitive unit, applying a light beam to the electrified photosensitive member to form an electrostatic latent image thereon, developing the electrostatic latent image to create a visible image and then transferring the visible image to printing paper; a nonvolatile memory means for storing data indicating a printing history of the photosensitive unit; processing means for updating the data stored in said nonvolatile memory means each time the printing operation is effected, said processing means including means for checking whether the data stored in said nonvolatile memory means has reached a value corresponding to a service life of said photosensitive unit, and means for generating a replacement requiring signal when said checking means detects that the data stored in said nonvolatile memory means has reached said value, wherein said nonvolatile memory means is a nonvolatile memory card, and said processing means includes a connecting section to which said nonvolatile memory card is removably attached; and stopper means for preventing removal of said nonvolatile memory card when the photosensitive unit has been set in the printing device.