Granted Patent
Utility
US 4,305,740 · App. 05/818,298
Filter material charging apparatus
Inventor:
Alan E. Revell
Patented Case
View Patent ↗
Granted: Dec 15, 1981
Filed: Jul 25, 1977
Inventor
Alan E. Revell
Assignee (at issue)
AMERICAN AIR FILTER COMPANY, 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.