Granted Patent
Utility
US 4,544,396 · App. 06/543,735
Method and apparatus for controlling currents in glass melter
Inventors:
John F. Krumwiede, William C. Harrell, William G. Hilliard, James E. Harris
Patented Case
View Patent ↗
Granted: Oct 1, 1985
Filed: Oct 20, 1983
Inventors
John F. Krumwiede
William C. Harrell
William G. Hilliard
James E. Harris
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.