Granted Patent
Utility
US 5,202,099 · App. 07/426,846
Angle of repose valve
Inventors:
James E. Boone, David W. Owens, Robert E. Farritor, Wesley D. Blank
Patented Case
View Patent ↗
Granted: Apr 13, 1993
Filed: Oct 26, 1989
Inventors
James E. Boone
David W. Owens
Robert E. Farritor
Wesley D. Blank
Assignee (at issue)
Ethyl 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.