Granted Patent
Utility
US 4,445,503 · App. 06/223,355
Percussor assembly
Inventor:
Harold R. Havstad
Patented Case
View Patent ↗
Granted: May 1, 1984
Filed: Jan 8, 1981
Inventor
Harold R. Havstad
Assignee (at issue)
Hudson Oxygen Therapy Sales 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.