Granted Patent
Utility
US 4,368,440 · App. 06/199,779
Fail-safe low-pass filtering circuit
Inventor:
John O. G. Darrow
Patented Case
View Patent ↗
Granted: Jan 11, 1983
Filed: Oct 23, 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.