Granted Patent
Utility
US 4,423,788 · App. 06/265,513
Agricultural furrow forming apparatus depth control
Inventors:
Edward L. Robinson, Jr., Lawerence D. Westerfield
Patented Case
View Patent ↗
Granted: Jan 3, 1984
Filed: May 20, 1981
Inventors
Edward L. Robinson, Jr.
Lawerence D. Westerfield
Assignee (at issue)
International Harvester Company
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.