Granted Patent
Utility
US 6,189,840 · App. 09/351,345
Roller device for displacement of railroad switching rails
Inventors:
Gilson Etore Mantovan, Isnad Torres Pires, Jose Roberto Fehlberg, Reynaldo Lopes Ferreira
Patented Case
View Patent ↗
Granted: Feb 20, 2001
Filed: Jul 12, 1999
Inventors
Gilson Etore Mantovan
Isnad Torres Pires
Jose Roberto Fehlberg
Reynaldo Lopes Ferreira
Assignee (at issue)
Companhia Vale do Rio Doce
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.