Granted Patent
Utility
US 5,214,934 · App. 07/857,927
Helical conveyor systems
Inventors:
James Palframan, James L. Peterson
Patented Case
View Patent ↗
Granted: Jun 1, 1993
Filed: Jul 9, 1992
Inventors
James Palframan
James L. Peterson
Assignee (at issue)
York Food Systems
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.