Granted Patent
Utility
US 4,689,969 · App. 06/860,135
Refrigerated gas separation apparatus
Inventor:
Leon R. Van Steenburgh, Jr.
Patented Case
View Patent ↗
Granted: Sep 1, 1987
Filed: May 6, 1986
Inventor
Leon R. Van Steenburgh, Jr.
Assignee (at issue)
Wilkerson 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.