Granted Patent
Utility
US 5,956,915 · App. 08/881,337
Tubular drill mast
Inventors:
James P. Piper, Carl D. Gilmore, Kenneth Hammel, Frank R. Szpek, Jr.
Patented Case
View Patent ↗
Granted: Sep 28, 1999
Filed: Jun 24, 1997
Inventors
James P. Piper
Carl D. Gilmore
Kenneth Hammel
Frank R. Szpek, Jr.
Assignee (at issue)
Bucyrus Intl. Inc.
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.