Granted Patent
Utility
US 4,900,374 · App. 07/397,826
Demagnetization of iron-neodymium-boron type permanent magnets without loss of coercivity
Inventor:
Viswanathan Panchanathan
Patented Case
View Patent ↗
Granted: Feb 13, 1990
Filed: Aug 24, 1989
Inventor
Viswanathan Panchanathan
Assignee (at issue)
General Motors LLC
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.