Granted Patent
Utility
US 5,307,939 · App. 07/912,462
Screening apparatus for papermaking pulp
Inventors:
Douglas L. G. Young, Oscar Luthi
Patented Case
View Patent ↗
Granted: May 3, 1994
Filed: Jul 13, 1992
Inventors
Douglas L. G. Young
Oscar Luthi
Assignee (at issue)
Ingersoll-Rand 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.