Granted Patent
Utility
US 4,435,122 · App. 06/239,427
Method and apparatus for pumping fiber suspensions
Inventors:
Toivo Niskanen, Frey Sundman, Jorma Tuomaala
Patented Case
View Patent ↗
Granted: Mar 6, 1984
Filed: Mar 2, 1981
Inventors
Toivo Niskanen
Frey Sundman
Jorma Tuomaala
Assignee (at issue)
A. Ahlstrom Osakeyhtio
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.