Granted Patent
Utility
US 5,048,876 · App. 07/431,024
Closure apparatus for pipes and vessels
Inventor:
Harvey A. Wallskog
Patented Case
View Patent ↗
Granted: Sep 17, 1991
Filed: Nov 2, 1989
Inventor
Harvey A. Wallskog
Assignee (at issue)
Fluor Corporation
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.