Granted Patent
Utility
US 4,242,866 · App. 05/960,059
By-pass valve
Inventor:
Raymond Williamson
Patented Case
View Patent ↗
Granted: Jan 6, 1981
Filed: Nov 13, 1978
Inventor
Raymond Williamson
Assignee (at issue)
ACF Industries Incorporated
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.