Granted Patent
Utility
US 4,977,786 · App. 07/466,937
Capacitive liquid level sensor
Inventor:
James E. Davis
Patented Case
View Patent ↗
Granted: Dec 18, 1990
Filed: Jan 18, 1990
Inventor
James E. Davis
Assignee (at issue)
E.I. DU PONT DE NEMOURS AND 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.