Granted Patent
Utility
US 6,072,938 · App. 09/134,119
Heater with medium-filled passive heating element
Inventors:
John Peterson, Chris Heflin
Patented Case
View Patent ↗
Granted: Jun 6, 2000
Filed: Aug 14, 1998
Inventors
John Peterson
Chris Heflin
Assignee (at issue)
Lakewood Engineering and Manufacturing Co.
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.