Granted Patent
Utility
US 6,700,342 · App. 10/208,251
Method and apparatus for high performance permanent magnet motor speed control with limited position information
Inventors:
Richard J. Hampo, Yifan Zhao
Patented Case
View Patent ↗
Granted: Mar 2, 2004
Filed: Jul 29, 2002
Inventors
Richard J. Hampo
Yifan Zhao
Assignee (at issue)
BALLARD POWER SYSTEMS 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.