Granted Patent
Utility
US 4,073,544 · App. 05/780,473
Continual quick service valve device
Inventor:
James E. Hart
Patented Case
View Patent ↗
Granted: Feb 14, 1978
Filed: Mar 23, 1977
Inventor
James E. Hart
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.