Granted Patent
Utility
US 5,657,839 · App. 08/561,361
Railway brake shoe
Inventor:
Joseph C. Kahr
Patented Case
View Patent ↗
Granted: Aug 19, 1997
Filed: Feb 26, 1996
Inventor
Joseph C. Kahr
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.