Granted Patent
Utility
US 4,327,508 · App. 06/213,805
Trencher digging chain sprocket drive
Inventor:
Stephen A. Youngers
Patented Case
View Patent ↗
Granted: May 4, 1982
Filed: Dec 8, 1980
Inventor
Stephen A. Youngers
Assignee (at issue)
J. I. Case Company
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.