Granted Patent
Utility
US 5,653,423 · App. 08/595,862
Knife gate valve with mechanically retained gate seat
Inventors:
Calvin Young, David L. Gambetta, Jon A. Hansen, Nolan D. King, Darrel J. DesRochers, Richard A. Sutherland
Patented Case
View Patent ↗
Granted: Aug 5, 1997
Filed: Feb 6, 1996
Inventors
Calvin Young
David L. Gambetta
Jon A. Hansen
Nolan D. King
Darrel J. DesRochers
Richard A. Sutherland
Assignee (at issue)
Technaflow, 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.