Granted Patent
Utility
US 5,159,982 · App. 07/736,087
Double walled riser
Inventor:
Joseph H. Hynes
Patented Case
View Patent ↗
Granted: Nov 3, 1992
Filed: Jul 26, 1991
Inventor
Joseph H. Hynes
Assignee (at issue)
Cooper Industries Holdings
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.