Granted Patent
Utility
US 5,726,447 · App. 08/679,647
Ionization chamber and mass spectrometer having a corona needle which is externally removable from a closed ionization chamber
Inventors:
Edward Aisawa, James L. Bertsch, J. Michael Flanagan, Darrell L. Gourley, Val C. Robinson, Joseph Vandenburg
Patented Case
View Patent ↗
Granted: Mar 10, 1998
Filed: Jul 12, 1996
Inventors
Edward Aisawa
James L. Bertsch
J. Michael Flanagan
Darrell L. Gourley
Val C. Robinson
Joseph Vandenburg
Assignee (at issue)
Hewlett-Packard Company, L.P.
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.