Granted Patent
Utility
US 4,884,943 · App. 07/209,634
Method and apparatus for pumping high-consistency fiber suspension
Inventor:
Toivo Niskanen
Patented Case
View Patent ↗
Granted: Dec 5, 1989
Filed: Jun 21, 1988
Inventor
Toivo Niskanen
Assignee (at issue)
A. Ahlstrom Corporation
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.