Granted Patent
Utility
US 4,768,022 · App. 06/917,685
Apparatus for generating auditory indicators
Inventor:
Roy D. Patterson
Patented Case
View Patent ↗
Granted: Aug 30, 1988
Filed: Oct 10, 1986
Inventor
Roy D. Patterson
Assignee (at issue)
NATIONAL RESEARCH DEVELOPMENT 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.