Granted Patent
Utility
US 5,638,263 · App. 08/351,822
Low and medium voltage PWM AC/DC power conversion method and apparatus
Inventors:
Kenneth E. Opal, Harry Abrams, Peter Willard Hammond
Patented Case
View Patent ↗
Granted: Jun 10, 1997
Filed: Dec 8, 1994
Inventors
Kenneth E. Opal
Harry Abrams
Peter Willard Hammond
Assignee (at issue)
Halmar Robicon Group
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.