Granted Patent
Utility
US 5,829,952 · App. 08/864,871
Check valve with a reversible valve ball and seat
Inventor:
Darrel W. Shadden
Patented Case
View Patent ↗
Granted: Nov 3, 1998
Filed: May 13, 1997
Inventor
Darrel W. Shadden
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.