Granted Patent
Utility
US 4,467,270 · App. 06/306,020
Automatic departure test unit for cab signal equipment
Inventors:
John M. McElroy, Charles E. Janney
Patented Case
View Patent ↗
Granted: Aug 21, 1984
Filed: Mar 31, 1981
Inventors
John M. McElroy
Charles E. Janney
Assignee (at issue)
American Standard 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.