Granted Patent
Utility
US 4,457,523 · App. 06/437,869
Torsionally flexible metallic annular seal
Inventors:
Horace P. Halling, Robert Alan Barrett
Patented Case
View Patent ↗
Granted: Jul 3, 1984
Filed: Oct 29, 1982
Inventors
Horace P. Halling
Robert Alan Barrett
Assignee (at issue)
Pressure Science Incorporated
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.