Granted Patent
Utility
US 6,647,973 · App. 10/166,812
Two-stage filtration assembly for a diesel engine crankcase ventilation system
Inventors:
Joshua D. Schueler, Michael D. Tombers
Patented Case
View Patent ↗
Granted: Nov 18, 2003
Filed: Jun 11, 2002
Inventors
Joshua D. Schueler
Michael D. Tombers
Assignee (at issue)
General Motors LLC
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.