Granted Patent
Utility
US 5,143,558 · App. 07/667,464
Method of heat treating metal parts in an integrated continuous and batch furnace system
Inventor:
John W. Smith
Patented Case
View Patent ↗
Granted: Sep 1, 1992
Filed: Mar 11, 1991
Inventor
John W. Smith
Assignee (at issue)
Thermo Process Systems Inc.
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.