Granted Patent
Utility
US 4,373,861 · App. 06/140,883
Axial-flow fan
Inventors:
Georg Papst, Siegfried Harmsen, Gunter Wrobel
Patented Case
View Patent ↗
Granted: Feb 15, 1983
Filed: Apr 16, 1980
Inventors
Georg Papst
Siegfried Harmsen
Gunter Wrobel
Assignee (at issue)
Papst Motoren GmbH & Co KG
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.