Granted Patent
Utility
US 4,557,157 · App. 06/474,858
Vehicle steering differential
Inventor:
Eldon D. Oestmann
Patented Case
View Patent ↗
Granted: Dec 10, 1985
Filed: Mar 14, 1983
Inventor
Eldon D. Oestmann
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.