Granted Patent
Utility
US 4,475,570 · App. 06/312,139
Anti-syphon freezeless water hydrant
Inventors:
Daniel W. Pike, Phillip Crawley, John L. Marshall, Steve A. Martin
Patented Case
View Patent ↗
Granted: Oct 9, 1984
Filed: Oct 16, 1981
Inventors
Daniel W. Pike
Phillip Crawley
John L. Marshall
Steve A. Martin
Assignee (at issue)
Prier Brass Manufacturing 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.