Granted Patent
Utility
US 4,256,318 · App. 06/144,676
Piston ring
Inventor:
Jerome J. Bush
Patented Case
View Patent ↗
Granted: Mar 17, 1981
Filed: Apr 28, 1980
Inventor
Jerome J. Bush
Assignee (at issue)
Sealed Power 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.