Granted Patent
Utility
US 4,221,216 · App. 05/883,362
Emergency escape breathing apparatus
Inventor:
Max L. Kranz
Patented Case
View Patent ↗
Granted: Sep 9, 1980
Filed: Mar 6, 1978
Inventor
Max L. Kranz
Assignee (at issue)
ROBERTSHAW CONTROLS PRIVATE LIMITED
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.