Granted Patent
Utility
US 6,631,541 · App. 09/924,300
Hammer piston handling apparatus
Inventors:
Donald E. Mosing, David L. Sipos
Patented Case
View Patent ↗
Granted: Oct 14, 2003
Filed: Aug 8, 2001
Inventors
Donald E. Mosing
David L. Sipos
Assignee (at issue)
Frank's Casing Crew and Rental Tools, 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.