Granted Patent
Utility
US 5,813,061 · App. 08/674,580
Air pressure driven vacuum sewer system
Inventor:
Hans Tornqist
Patented Case
View Patent ↗
Granted: Sep 29, 1998
Filed: Jul 5, 1996
Inventor
Hans Tornqist
Assignee (at issue)
Evac AB
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.