Granted Patent
Utility
US 4,855,567 · App. 07/144,572
Frost control system for high-speed horizontal folding doors
Inventor:
Louis B. Mueller
Patented Case
View Patent ↗
Granted: Aug 8, 1989
Filed: Jan 15, 1988
Inventor
Louis B. Mueller
Assignee (at issue)
Rytec Corporation
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.