Granted Patent
Utility
US 4,290,986 · App. 06/048,576
Method for controlling a plastic extruder
Inventor:
John E. Koschmann
Patented Case
View Patent ↗
Granted: Sep 22, 1981
Filed: Jun 14, 1979
Inventor
John E. Koschmann
Assignee (at issue)
Owens-Illinois 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.