Granted Patent
Utility
US 4,806,887 · App. 07/054,524
R-switch with transformers
Inventor:
Henry Y. M. Au-Yeung
Patented Case
View Patent ↗
Granted: Feb 21, 1989
Filed: May 27, 1987
Inventor
Henry Y. M. Au-Yeung
Assignee (at issue)
COM DEV LTD.
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.