Granted Patent
Utility
US 4,804,892 · App. 07/072,264
Collectorless direct current motor, driver circuit for a drive and method of operating a collectorless direct current motor
Inventor:
Rolf Muller
Patented Case
View Patent ↗
Granted: Feb 14, 1989
Filed: Jun 22, 1987
Inventor
Rolf Muller
Assignee (at issue)
Papst Motoren GmbH & Co KG
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.