Granted Patent
Utility
US 4,276,159 · App. 06/161,100
Apparatus for screening paper fiber stock
Inventor:
Donald Lehman
Patented Case
View Patent ↗
Granted: Jun 30, 1981
Filed: Jun 19, 1980
Inventor
Donald Lehman
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.