Granted Patent
Utility
US 4,838,864 · App. 07/120,620
Pressure controller
Inventor:
Carl W. Peterson
Patented Case
View Patent ↗
Granted: Jun 13, 1989
Filed: Nov 13, 1987
Inventor
Carl W. Peterson
Assignee (at issue)
Mansfield Scientific, 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.