Granted Patent
Utility
US 4,272,231 · App. 06/020,793
Air cooling ring for plastic film with independent lubricating air for film guide surface
Inventor:
Charles M. Schott, Jr.
Patented Case
View Patent ↗
Granted: Jun 9, 1981
Filed: Mar 15, 1979
Inventor
Charles M. Schott, Jr.
Assignee (at issue)
Gloucester Engineering Co., 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.