Granted Patent
Utility
US 4,237,571 · App. 06/039,314
Floor polisher with gear drive
Inventor:
Bertel S. Nelson
Patented Case
View Patent ↗
Granted: Dec 9, 1980
Filed: May 16, 1979
Inventor
Bertel S. Nelson
Assignee (at issue)
Clarke-Gravely 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.