Granted Patent
Utility
US 4,232,709 · App. 05/953,146
Four-way ball valve
Inventor:
Michael T. Zoric
Patented Case
View Patent ↗
Granted: Nov 11, 1980
Filed: Oct 20, 1978
Inventor
Michael T. Zoric
Assignee (at issue)
Westinghouse Air Brake Co.
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.