Method and device for displaying an exchange message for a process cartridge with a process cartridge comprising a non-volatile memory for storing data values

A device for displaying an exchange message for a process cartridge installed within a body of an image forming apparatus, said device comprising:

• said process cartridge comprising a first non-volatile memory for storing a first value representative of a number of times a toner cartridge has required exchange for a new toner cartridge, a photosensitive drum, a toner sensor for detecting a quantity of toner remaining within said toner cartridge, a cleaning blade and a waste toner receptacle combined into a unitary structure capable of being installed within and removed from said body;
• said toner cartridge for storing said toner, said toner cartridge comprising a second non-volatile memory for storing a second value representative of said quantity of said toner remaining within said toner cartridge, said toner cartridge capable of being attachable to and detachable from said process cartridge;
• display means for displaying predetermined messages;
• and
• control means for receiving a print command from a host computer and controlling a printing operation performed by said image forming apparatus, said control means incrementing said second value stored in said second non-volatile memory whenever an absence of said toner is detected by said toner sensor, said control means enabling said display means to display said exchange message indicating that said process cartridge should be exchanged for a new process cartridge when said first value stored in said first non-volatile memory equals a first predetermined value.

A method for displaying an exchange message for a process cartridge installed within a body of an image forming apparatus comprising:

• said process cartridge comprised of a non-volatile memory for storing first and second data values, a photosensitive drum, a toner sensor for detecting a quantity of toner remaining within a toner cartridge, a cleaning blade and a waste toner receptacle combined as a unitary structure capable of being installed within and removed from said body;
• and a display means for displaying predetermined messages, said method comprising the steps of:
• detecting said quantity of said toner remaining within said toner cartridge via said toner sensor;
• incrementing said first data value representative of a number of times said toner cartridge has required exchange for a new toner cartridge when said toner sensor detects a toner absence state;
• detecting when a toner full state is recovered via said toner sensor;
• incrementing said second data value when said toner full state is recovered;
• and
• displaying, via said display means, said exchange message indicating that said process cartridge should be exchanged for a new process cartridge when said first data value equals a predetermined value.