Granted Patent
Utility
US 4,231,579 · App. 05/923,838
Sealing ring
Inventor:
John Scannell
Patented Case
View Patent ↗
Granted: Nov 4, 1980
Filed: Jul 12, 1978
Inventor
John Scannell
Assignee (at issue)
Parker-Hannifin 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.