Granted Patent
Utility
US 5,823,539 · App. 08/426,780
Environmentally safe pump having a bellows seal and a split ring shaft seal
Inventor:
Robert E. Rockwood
Patented Case
View Patent ↗
Granted: Oct 20, 1998
Filed: Apr 21, 1995
Inventor
Robert E. Rockwood
Assignee (at issue)
Environamics 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.