Granted Patent
Utility
US 6,663,336 · App. 09/849,661
Trough lifting mechanism
Inventors:
Jack Fletcher, Donald Boyd, Michael Hayden
Patented Case
View Patent ↗
Granted: Dec 16, 2003
Filed: May 4, 2001
Inventors
Jack Fletcher
Donald Boyd
Michael Hayden
Assignee (at issue)
Shaffer Manufacturing Corporation
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.