Patents by Inventor Christian G. Midgley, Sr.

Christian G. Midgley, Sr. has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Monitoring system with dual memory for electrophotographic printing machines using replaceable cartridges
    Patent number: 5283613
    Abstract: A monitoring system for replaceable units, such as toner cartridges in an electrophotographic printer, includes on the unit an electronic count memory and an electronic flag memory. The count memory maintains a one-by-one count of prints made with the cartridge. The flag memory includes a series of bits which are alterable from a first state to a second state but not alterable from the second state to the first state. The bits in the flag memory are altered at predetermined intervals as prints are made with the cartridge. The flag memory is used as a check to override unauthorized manipulation of the count memory.
    Type: Grant
    Filed: February 19, 1993
    Date of Patent: February 1, 1994
    Assignee: Xerox Corporation
    Inventor: Christian G. Midgley, Sr.