Granted Patent
Utility
US 4,397,173 · App. 06/277,746
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Inventors:
Larry G. Eftefield, Edward R. Horton
Patented Case
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Granted: Aug 9, 1983
Filed: Mar 3, 1981
Inventors
Larry G. Eftefield
Edward R. Horton
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.