Granted Patent
Utility
US 4,955,437 · App. 07/463,257
Underground electromagnetic tillage depth sensor
Inventor:
Carl E. Bohman
Patented Case
View Patent ↗
Granted: Sep 11, 1990
Filed: Jan 9, 1990
Inventor
Carl E. Bohman
Assignee (at issue)
Ford New Holland, Inc.
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.