Granted Patent
Utility
US 5,222,369 · App. 07/815,481
Refrigerant recovery device with vacuum operated check valve
Inventors:
John P. Hancock, Ralph A. McClelland, Jeffrey S. James
Patented Case
View Patent ↗
Granted: Jun 29, 1993
Filed: Dec 31, 1991
Inventors
John P. Hancock
Ralph A. McClelland
Jeffrey S. James
Assignee (at issue)
K-Whit Tools, Inc.
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.