Granted Patent
Utility
US 4,753,534 · App. 07/055,478
Mixing apparatus
Inventor:
Stephen L. Markle
Patented Case
View Patent ↗
Granted: Jun 28, 1988
Filed: May 28, 1987
Inventor
Stephen L. Markle
Assignee (at issue)
Federal Signal 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.