Granted Patent
Utility
US 4,483,509 · App. 06/390,324
Guillotine valve assembly
Inventors:
Ronald B. Lewcock, James Lyons
Patented Case
View Patent ↗
Granted: Nov 20, 1984
Filed: Jun 21, 1982
Inventors
Ronald B. Lewcock
James Lyons
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.