Granted Patent
Utility
US 4,681,139 · App. 06/848,763
Elastomer ball check valve
Inventor:
Ralph Anthony Falconer
Patented Case
View Patent ↗
Granted: Jul 21, 1987
Filed: Apr 7, 1986
Inventor
Ralph Anthony Falconer
Assignee (at issue)
Jandy Industries Inc
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.