Granted Patent
Utility
US 4,612,957 · App. 06/695,909
Vacuum pump and trap combination
Inventors:
Lutz Arndt, Paul Bachmann, Hanns-Peter Berges, Wolfgang Leier, Dieter Vorberg
Patented Case
View Patent ↗
Granted: Sep 23, 1986
Filed: Jan 29, 1985
Inventors
Lutz Arndt
Paul Bachmann
Hanns-Peter Berges
Wolfgang Leier
Dieter Vorberg
Assignee (at issue)
Leybold-Heraeus GmbH
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.