Granted Patent
Utility
US 5,390,772 · App. 08/092,643
Switchable high speed frog mechanism
Inventors:
Cuong Manh Ta, Randel C. Anderson
Patented Case
View Patent ↗
Granted: Feb 21, 1995
Filed: Jul 16, 1993
Inventors
Cuong Manh Ta
Randel C. Anderson
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.