Granted Patent
Utility
US 5,454,936 · App. 08/094,838
Vacuum toilet system
Inventors:
Arne Ask, Sven Oldfelt, Harald A. A. Wallgren, Raymond L. Wilhelm
Patented Case
View Patent ↗
Granted: Oct 3, 1995
Filed: Jul 20, 1993
Inventors
Arne Ask
Sven Oldfelt
Harald A. A. Wallgren
Raymond L. Wilhelm
Assignee (at issue)
Oy Wartsila 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.