Granted Patent
Utility
US 4,444,410 · App. 06/350,693
Ball hitch apparatus
Inventor:
E. Joel Martin
Patented Case
View Patent ↗
Granted: Apr 24, 1984
Filed: Feb 22, 1982
Inventor
E. Joel Martin
Assignee (at issue)
Sperry Corp.
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.