Granted Patent
Utility
US 4,606,340 · App. 06/513,699
Combined pressure compensating exhalation and anti-suffocation valve
Inventor:
William K. Ansite
Patented Case
View Patent ↗
Granted: Aug 19, 1986
Filed: Jul 14, 1983
Inventor
William K. Ansite
Assignee (at issue)
Figgie Inernational 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.