Granted Patent
Utility
US 4,570,735 · App. 06/663,267
Dual rotary valve for variable assist power steering gear for automotive vehicles
Inventor:
James J. Duffy
Patented Case
View Patent ↗
Granted: Feb 18, 1986
Filed: Oct 22, 1984
Inventor
James J. Duffy
Assignee (at issue)
Ford Motor 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.