Granted Patent
Utility
US 6,693,809 · App. 10/222,310
Device for equal-rated parallel operation of single-or three-phase voltage sources
Inventor:
Alfred Engler
Patented Case
View Patent ↗
Granted: Feb 17, 2004
Filed: Aug 16, 2002
Inventor
Alfred Engler
Assignee (at issue)
Institut fuer Solare Energieversorgungs-technik (ISET) Verein an der Universitaet Gesamthochschule Kassel e.V.
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.