Granted Patent
Utility
US 6,550,394 · App. 10/095,230
Retractable auxiliary bumper for hydraulic or pneumatic railway suspensions
Inventor:
Richard B. Polley
Patented Case
View Patent ↗
Granted: Apr 22, 2003
Filed: Mar 11, 2002
Inventor
Richard B. Polley
Assignee (at issue)
Buckeye Steel Castings Company
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.