Granted Patent
Utility
US 4,556,408 · App. 06/637,103
Dual ring segmented block tempering ring
Inventors:
Michael T. Fecik, Robert G. Frank, John J. Ewing
Patented Case
View Patent ↗
Granted: Dec 3, 1985
Filed: Aug 2, 1984
Inventors
Michael T. Fecik
Robert G. Frank
John J. Ewing
Assignee (at issue)
PPG Industries, 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.