Granted Patent
Utility
US 5,123,594 · App. 07/542,193
Vehicle heating system with an engine-independent heater
Inventor:
Michael Humburg
Patented Case
View Patent ↗
Granted: Jun 23, 1992
Filed: Jun 21, 1990
Inventor
Michael Humburg
Assignee (at issue)
J. Eberspacher
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.