Granted Patent
Utility
US 4,639,261 · App. 06/584,819
High efficiency air filter
Inventors:
Clarence B. Pittman, George H. Cadwell, Jr.
Patented Case
View Patent ↗
Granted: Jan 27, 1987
Filed: Feb 29, 1984
Inventors
Clarence B. Pittman
George H. Cadwell, Jr.
Assignee (at issue)
FLANDERS FILTERS, 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.