Granted Patent
Utility
US 4,727,663 · App. 06/791,117
Excavating tooth having a lock including a basket spring
Inventor:
Frederick C. Hahn
Patented Case
View Patent ↗
Granted: Mar 1, 1988
Filed: Oct 24, 1985
Inventor
Frederick C. Hahn
Assignee (at issue)
ESCO GROUP 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.