Granted Patent
Utility
US 4,255,746 · App. 05/853,193
Emergency lighting and fire detector system
Inventors:
Robert W. Johnson, William J. Raddi
Patented Case
View Patent ↗
Granted: Mar 10, 1981
Filed: Nov 21, 1977
Inventors
Robert W. Johnson
William J. Raddi
Assignee (at issue)
ESB Incorporated
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.