Granted Patent
Utility
US 4,850,842 · App. 07/179,466
Screw extruder
Inventor:
Terrance L. Van Alstine
Patented Case
View Patent ↗
Granted: Jul 25, 1989
Filed: Apr 8, 1988
Inventor
Terrance L. Van Alstine
Assignee (at issue)
Nabisco Brands, 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.