Granted Patent
Utility
US 5,217,512 · App. 07/890,527
Apparatus for filtering debris from a moving airstream
Inventor:
Roger D. Williams
Patented Case
View Patent ↗
Granted: Jun 8, 1993
Filed: May 28, 1992
Inventor
Roger D. Williams
Assignee (at issue)
Pneumafil 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.