Granted Patent
Utility
US 4,014,580 · App. 05/700,383
Emergency brake valve device for railway vehicles
Inventor:
Robert J. Bridigum
Patented Case
View Patent ↗
Granted: Mar 29, 1977
Filed: Jun 28, 1976
Inventor
Robert J. Bridigum
Assignee (at issue)
Westinghouse Air Brake Co.
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.