Granted Patent
Utility
US 4,640,230 · App. 06/806,708
Rotating helical conveyor system
Inventor:
Gerardus H. Van Rooijen
Patented Case
View Patent ↗
Granted: Feb 3, 1987
Filed: Dec 9, 1985
Inventor
Gerardus H. Van Rooijen
Assignee (at issue)
Chore-Time Equipment, 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.