Granted Patent
Utility
US 4,723,738 · App. 06/878,711
Railway track circuit for electrified territory including impedance bonds and insulated joints
Inventor:
Raymond C. Franke
Patented Case
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Granted: Feb 9, 1988
Filed: Jun 26, 1986
Inventor
Raymond C. Franke
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.