Granted Patent
Utility
US 4,303,194 · App. 06/125,725
Smoke prevention apparatus
Inventors:
Fritz Kengle, James E. Young
Patented Case
View Patent ↗
Granted: Dec 1, 1981
Filed: Feb 28, 1980
Inventors
Fritz Kengle
James E. Young
Assignees (at issue)
U.S. Steel Corporation
Customized Controls, 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.