Granted Patent
Utility
US 4,886,540 · App. 07/223,913
Blow back control device for a glass sheet tempering system
Inventor:
David B. Nitschke
Patented Case
View Patent ↗
Granted: Dec 12, 1989
Filed: Jul 25, 1988
Inventor
David B. Nitschke
Assignee (at issue)
Glasstech International L.P.
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.