Granted Patent
Utility
US 4,370,675 · App. 06/222,816
Doorbell actuated television security system
Inventor:
William E. Cohn
Patented Case
View Patent ↗
Granted: Jan 25, 1983
Filed: Jan 5, 1981
Inventor
William E. Cohn
Assignee (at issue)
Zenith Radio Corporation
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.