Granted Patent
Utility
US 4,365,442 · App. 06/190,477
Automatic door control system
Inventor:
Harold A. Speer
Patented Case
View Patent ↗
Granted: Dec 28, 1982
Filed: Sep 24, 1980
Inventor
Harold A. Speer
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.