Granted Patent
Utility
US 4,355,211 · App. 06/233,207
Push button key modules
Inventor:
Frederick Steiner
Patented Case
View Patent ↗
Granted: Oct 19, 1982
Filed: Feb 10, 1981
Inventor
Frederick Steiner
Assignee (at issue)
Plessey Overseas Limited
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.