Granted Patent
Utility
US 4,709,950 · App. 06/623,032
Crash bar door locking device
Inventor:
Zedekiah Z. Zortman
Patented Case
View Patent ↗
Granted: Dec 1, 1987
Filed: Jun 21, 1984
Inventor
Zedekiah Z. Zortman
Assignee (at issue)
American Device Manufacturing 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.