Granted Patent
Utility
US 5,159,641 · App. 07/739,151
Microphone circuit control mechanism for breathing apparatus
Inventors:
Timothy J. Sopko, William D. Siska, Vernon C. Lenz
Patented Case
View Patent ↗
Granted: Oct 27, 1992
Filed: Jul 31, 1991
Inventors
Timothy J. Sopko
William D. Siska
Vernon C. Lenz
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.