Granted Patent
Utility
US 4,746,221 · App. 06/861,012
Stirrer for use in liquid storage tanks
Inventors:
Katsuji Okumura, Hiroshi Maeda, Isao Taoka
Patented Case
View Patent ↗
Granted: May 24, 1988
Filed: May 8, 1986
Inventors
Katsuji Okumura
Hiroshi Maeda
Isao Taoka
Assignees (at issue)
Nippon Mining Company Limited
Automax, Inc.
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.