Granted Patent
Utility
US 5,293,009 · App. 07/886,069
Dust protection cap for conical loudspeaker
Inventor:
Rudiger Fleischer
Patented Case
View Patent ↗
Granted: Mar 8, 1994
Filed: May 20, 1992
Inventor
Rudiger Fleischer
Assignee (at issue)
Nokia (Unterhaltungselektronik/(Deutschland) GmbH
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.