Granted Patent
Utility
US 4,447,836 · App. 06/424,788
Recording apparatus for cassette copying
Inventors:
Dean W. Flygstad, Bill H. Wehrmacher
Patented Case
View Patent ↗
Granted: May 8, 1984
Filed: Sep 27, 1982
Inventors
Dean W. Flygstad
Bill H. Wehrmacher
Assignee (at issue)
Telex Communications, 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.