Granted Patent
Utility
US 4,256,291 · App. 06/087,520
Three-positions sliding gate valve
Inventors:
Enrico Dellepiane, Roberto Ricci, Giovanni Timossi
Patented Case
View Patent ↗
Granted: Mar 17, 1981
Filed: Oct 23, 1979
Inventors
Enrico Dellepiane
Roberto Ricci
Giovanni Timossi
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.