Granted Patent
Utility
US 4,757,689 · App. 06/922,034
Cryopump, and a method for the operation thereof
Inventors:
Werner Bachler, Hans-Joachim Forth, Hans-Hermann Klein, Wilhelm Strasser
Patented Case
View Patent ↗
Granted: Jul 19, 1988
Filed: Oct 22, 1986
Inventors
Werner Bachler
Hans-Joachim Forth
Hans-Hermann Klein
Wilhelm Strasser
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.