Granted Patent
Utility
US 5,870,026 · App. 08/892,645
Brush wear indicator
Inventor:
Keith C. Challenger
Patented Case
View Patent ↗
Granted: Feb 9, 1999
Filed: Jul 15, 1997
Inventor
Keith C. Challenger
Assignee (at issue)
THE MORGAN CRUCIBLE COMPANY PLC
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.