Granted Patent
Utility
US 4,437,812 · App. 06/305,426
Single-pump multiple stroke proportioning for gradient elution liquid chromatography
Inventors:
Ahmad Abu-Shumays, John C. Helmer, Stephen J. Luchetti
Patented Case
View Patent ↗
Granted: Mar 20, 1984
Filed: Sep 25, 1981
Inventors
Ahmad Abu-Shumays
John C. Helmer
Stephen J. Luchetti
Assignee (at issue)
Varian, 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.