Granted Patent
Utility
US 6,141,979 · App. 09/443,810
Dual heat exchanger wheels with variable speed
Inventor:
Steven Dunlap
Patented Case
View Patent ↗
Granted: Nov 7, 2000
Filed: Nov 19, 1999
Inventor
Steven Dunlap
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.