Granted Patent
Utility
US 4,358,206 · App. 06/221,243
Draft tube apparatus
Inventor:
Marlin D. Schutte
Patented Case
View Patent ↗
Granted: Nov 9, 1982
Filed: Dec 30, 1980
Inventor
Marlin D. Schutte
Assignee (at issue)
Federal Signal 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.