Granted Patent
Utility
US 4,608,674 · App. 06/406,020
Constant range ultrasonic motion detector
Inventor:
John K. Guscott
Patented Case
View Patent ↗
Granted: Aug 26, 1986
Filed: Aug 6, 1982
Inventor
John K. Guscott
Assignee (at issue)
American District Telegraph Company
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.