Granted Patent
Utility
US 5,961,295 · App. 08/887,626
Mixed flow liquid ring pumps
Inventors:
Harold K. Haavik, Douglas Sweet
Patented Case
View Patent ↗
Granted: Oct 5, 1999
Filed: Jul 3, 1997
Inventors
Harold K. Haavik
Douglas Sweet
Assignee (at issue)
The Nash Engineering Company
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.