Granted Patent
Utility
US 4,313,504 · App. 06/102,198
Tandem ripper assembly
Inventor:
Robert L. Fischer
Patented Case
View Patent ↗
Granted: Feb 2, 1982
Filed: Aug 13, 1979
Inventor
Robert L. Fischer
Assignee (at issue)
Caterpillar Tractor Co.
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.