Granted Patent
Utility
US 4,823,431 · App. 07/055,833
Fan blade cleaning device
Inventor:
Weda B. Carpenter
Patented Case
View Patent ↗
Granted: Apr 25, 1989
Filed: Jun 1, 1987
Inventor
Weda B. Carpenter
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.