Granted Patent
Utility
US 4,601,307 · App. 06/752,633
Lubricated plug valve
Inventor:
Bruce Johnson
Patented Case
View Patent ↗
Granted: Jul 22, 1986
Filed: Jul 8, 1985
Inventor
Bruce Johnson
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.