Granted Patent
Utility
US 4,856,794 · App. 07/077,132
Oil seal with antirotation ribs
Inventors:
Douglas B. Boyers, Steven R. Wilkening
Patented Case
View Patent ↗
Granted: Aug 15, 1989
Filed: Jul 23, 1987
Inventors
Douglas B. Boyers
Steven R. Wilkening
Assignee (at issue)
Federal-Mogul LLC
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.