Granted Patent
Utility
US 4,383,213 · App. 06/288,256
Triodyne
Inventor:
Joseph M. Tyrner
Patented Case
View Patent ↗
Granted: May 10, 1983
Filed: Jul 27, 1981
Inventor
Joseph M. Tyrner
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.