Granted Patent
Utility
US 4,481,663 · App. 06/494,137
Network for use with piezoceramic transducer
Inventor:
Paul B. Spranger
Patented Case
View Patent ↗
Granted: Nov 6, 1984
Filed: May 16, 1983
Inventor
Paul B. Spranger
Assignee (at issue)
Altec, 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.