Granted Patent
Utility
US 4,544,490 · App. 06/569,135
Method and system for recovering coal fines from pipe line coal slurry
Inventors:
Paul R. Erickson, Kenneth Pietila
Patented Case
View Patent ↗
Granted: Oct 1, 1985
Filed: Jan 9, 1984
Inventors
Paul R. Erickson
Kenneth Pietila
Assignee (at issue)
REXNORD GMBH
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.