Granted Patent
Utility
US 4,830,274 · App. 07/268,743
Pressure independent VAV valve with pressure dependent backup
Inventors:
Tedd P. Johnson, Ronald J. Lievens
Patented Case
View Patent ↗
Granted: May 16, 1989
Filed: Nov 8, 1988
Inventors
Tedd P. Johnson
Ronald J. Lievens
Assignee (at issue)
American Standard 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.