Granted Patent
Utility
US 4,420,727 · App. 06/307,484
Self oscillating acoustic displacement detector
Inventor:
William G. Rau
Patented Case
View Patent ↗
Granted: Dec 13, 1983
Filed: Oct 1, 1981
Inventor
William G. Rau
Assignee (at issue)
Burroughs, Inc.
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.