Granted Patent
Utility
US 4,381,205 · App. 06/365,531
Metal quenching process
Inventor:
Joseph F. Warchol
Patented Case
View Patent ↗
Granted: Apr 26, 1983
Filed: Apr 5, 1982
Inventor
Joseph F. Warchol
Assignee (at issue)
E. F. Houghton & Company
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.