Granted Patent
Utility
US 6,446,820 · App. 09/657,297
Railcar draft gear assembly and system
Inventors:
Ronald E. Barker, Charles E. Burkhart, Marlin E. Clark, John F. Deppen, V. Terrey Hawthorne, Horst T. Kaufhold, Jay P. Monaco, Julius I. Pershwitz, John J. Steffen
Patented Case
View Patent ↗
Granted: Sep 10, 2002
Filed: Sep 7, 2000
Inventors
Ronald E. Barker
Charles E. Burkhart
Marlin E. Clark
John F. Deppen
V. Terrey Hawthorne
Horst T. Kaufhold
Jay P. Monaco
Julius I. Pershwitz
John J. Steffen
Assignee (at issue)
AMSTED INDUSTRIES INCORPORATED
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.