Granted Patent
Utility
US 4,483,316 · App. 06/540,370
Air ventilation system
Inventors:
Frederick F. Fritz, Ralph L. Daigle
Patented Case
View Patent ↗
Granted: Nov 20, 1984
Filed: Oct 11, 1983
Inventors
Frederick F. Fritz
Ralph L. Daigle
Assignee (at issue)
Alco Foodservice Equipment 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.