Granted Patent
Utility
US 4,374,569 · App. 06/288,109
Furnace draft control system with electronic loss-of-draft timer
Inventor:
Thomas E. Hayes
Patented Case
View Patent ↗
Granted: Feb 22, 1983
Filed: Jul 29, 1981
Inventor
Thomas E. Hayes
Assignee (at issue)
Johnson Controls, 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.