Granted Patent
Utility
US 4,956,891 · App. 07/483,260
Floor cleaner
Inventor:
Richard F. Wulff
Patented Case
View Patent ↗
Granted: Sep 18, 1990
Filed: Feb 21, 1990
Inventor
Richard F. Wulff
Assignee (at issue)
Castex Industries, 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.