Granted Patent
Utility
US 4,691,721 · App. 06/679,259
Volumetric gravity feed liquid dispenser
Inventor:
David L. Nystuen
Patented Case
View Patent ↗
Granted: Sep 8, 1987
Filed: Dec 7, 1984
Inventor
David L. Nystuen
Assignee (at issue)
ECOLAB 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.