Granted Patent
Utility
US 4,720,117 · App. 06/851,722
Hand-pedalling attachment for wheel-chairs
Inventor:
Carl Hay
Patented Case
View Patent ↗
Granted: Jan 19, 1988
Filed: Apr 14, 1986
Inventor
Carl Hay
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.