Granted Patent
Utility
US 4,780,053 · App. 06/848,754
Method and apparatus for pumping fiber suspensions
Inventor:
Johan Gullichsen
Patented Case
View Patent ↗
Granted: Oct 25, 1988
Filed: Apr 4, 1986
Inventor
Johan Gullichsen
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.