Granted Patent
Utility
US 5,231,725 · App. 07/907,858
No-tool brush changing means
Inventors:
Robert D. Hennessey, Michael S. Wilmo
Patented Case
View Patent ↗
Granted: Aug 3, 1993
Filed: Jul 2, 1992
Inventors
Robert D. Hennessey
Michael S. Wilmo
Assignee (at issue)
TENNANT 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.