Granted Patent
Utility
US 5,104,231 · App. 07/736,177
Vortex mixer drive
Inventors:
Charles F. Collier, James Daniel Riall
Patented Case
View Patent ↗
Granted: Apr 14, 1992
Filed: Jul 26, 1991
Inventors
Charles F. Collier
James Daniel Riall
Assignee (at issue)
E.I. DU PONT DE NEMOURS AND COMPANY
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.