Granted Patent
Utility
US 4,487,216 · App. 06/406,346
Valve seal for fire safe or high temperature valves
Inventors:
James E. Barker, James C. Hadley
Patented Case
View Patent ↗
Granted: Dec 11, 1984
Filed: Aug 9, 1982
Inventors
James E. Barker
James C. Hadley
Assignee (at issue)
Federal Signal Corporation
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.