Granted Patent
Utility
US 4,231,698 · App. 05/867,704
System for one-hand control of two winches during hoisting of closed clamshell, with differentiation
Inventor:
William J. Lado
Patented Case
View Patent ↗
Granted: Nov 4, 1980
Filed: Jan 9, 1978
Inventor
William J. Lado
Assignee (at issue)
Pettibone, LLC
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.