Granted Patent
Utility
US 5,953,920 · App. 08/975,766
Tapered pulse tube for pulse tube refrigerators
Inventors:
Gregory W. Swift, Jeffrey R. Olson
Patented Case
View Patent ↗
Granted: Sep 21, 1999
Filed: Nov 21, 1997
Inventors
Gregory W. Swift
Jeffrey R. Olson
Assignee (at issue)
THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
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.