Granted Patent
Utility
US 4,397,575 · App. 06/305,762
Ribbon lift and feed mechanism for a typewriter
Inventor:
Charles Stanley Aldrich
Patented Case
View Patent ↗
Granted: Aug 9, 1983
Filed: Sep 25, 1981
Inventor
Charles Stanley Aldrich
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.