Granted Patent
Utility
US 4,440,022 · App. 06/419,103
Liquid-level detection
Inventor:
Ronald A. Masom
Patented Case
View Patent ↗
Granted: Apr 3, 1984
Filed: Sep 16, 1982
Inventor
Ronald A. Masom
Assignee (at issue)
Smiths Industries Public Limited 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.