Granted Patent
Utility
US 4,267,035 · App. 06/070,209
Pressurized rotary screening apparatus
Inventor:
Andrew Martin
Patented Case
View Patent ↗
Granted: May 12, 1981
Filed: Aug 27, 1979
Inventor
Andrew Martin
Assignee (at issue)
Black Clawson 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.