Granted Patent
Utility
US 4,334,666 · App. 06/145,903
Expanding gate valve with position responsive interlock
Inventors:
Patricio D. Alvarez, Robert Trevino
Patented Case
View Patent ↗
Granted: Jun 15, 1982
Filed: May 2, 1980
Inventors
Patricio D. Alvarez
Robert Trevino
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.