Granted Patent
Utility
US 4,491,917 · App. 06/266,306
Door control systems
Inventors:
Philip M. Higgins, William B. MacKenna, Lawrence G. Sickels, Richard A. Stumpf
Patented Case
View Patent ↗
Granted: Jan 1, 1985
Filed: May 22, 1981
Inventors
Philip M. Higgins
William B. MacKenna
Lawrence G. Sickels
Richard A. Stumpf
Assignee (at issue)
VAPOR 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.