Granted Patent
Utility
US 5,215,685 · App. 07/868,517
Humidifier with water sealed impeller unit
Inventor:
Frank Marino
Patented Case
View Patent ↗
Granted: Jun 1, 1993
Filed: Apr 15, 1992
Inventor
Frank Marino
Assignee (at issue)
Duracraft Corp.
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.