Granted Patent
Utility
US 4,648,552 · App. 06/837,888
Control installation for variable volume air diffusers
Inventors:
Melvin C. Carlson, Raymond H. Dean
Patented Case
View Patent ↗
Granted: Mar 10, 1987
Filed: Mar 10, 1986
Inventors
Melvin C. Carlson
Raymond H. Dean
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.