Granted Patent
Utility
US 4,417,850 · App. 06/451,555
Vertical column pump
Inventors:
Richard Hacker, James F. Tesch
Patented Case
View Patent ↗
Granted: Nov 29, 1983
Filed: Dec 20, 1982
Inventors
Richard Hacker
James F. Tesch
Assignee (at issue)
Allis-Chalmers Corporation
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.