Granted Patent
Utility
US 4,996,487 · App. 07/342,058
Apparatus for detecting failure of thermal heaters in ink jet printers
Inventors:
Ray A. McSparran, William S. Moore, James R. Wooden
Patented Case
View Patent ↗
Granted: Feb 26, 1991
Filed: Apr 24, 1989
Inventors
Ray A. McSparran
William S. Moore
James R. Wooden
Assignee (at issue)
International Business Machines 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.