Granted Patent
Utility
US 4,314,237 · App. 06/153,493
Fail-safe acknowledging circuit
Inventor:
John O. G. Darrow
Patented Case
View Patent ↗
Granted: Feb 2, 1982
Filed: May 27, 1980
Inventor
John O. G. Darrow
Assignee (at issue)
American Standard Inc.
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.