Granted Patent
Utility
US 4,216,062 · App. 06/008,992
Sealing means for a coke oven chuck door
Inventors:
Calvin E. Kelly, Richard W. Stanley
Patented Case
View Patent ↗
Granted: Aug 5, 1980
Filed: Feb 5, 1979
Inventors
Calvin E. Kelly
Richard W. Stanley
Assignee (at issue)
United States Steel Corporation
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.