Granted Patent
Utility
US 6,087,738 · App. 09/137,016
Variable output three-phase transformer
Inventor:
Peter Willard Hammond
Patented Case
View Patent ↗
Granted: Jul 11, 2000
Filed: Aug 20, 1998
Inventor
Peter Willard Hammond
Assignee (at issue)
Robicon Corporation
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.