Granted Patent
Utility
US 6,516,873 · App. 09/645,312
Heat exchanger
Inventor:
Ronald L. Haugen
Patented Case
View Patent ↗
Granted: Feb 11, 2003
Filed: Aug 25, 2000
Inventor
Ronald L. Haugen
Assignee (at issue)
Ingersoll-Rand Company
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.