Granted Patent
Utility
US 4,557,474 · App. 06/622,813
Duplex document copying machines
Inventors:
James W. Davis, Thomas J. DiFloria, Larry D. Propst
Patented Case
View Patent ↗
Granted: Dec 10, 1985
Filed: Jun 21, 1984
Inventors
James W. Davis
Thomas J. DiFloria
Larry D. Propst
Assignee (at issue)
The Mead Corporation
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.