Granted Patent
Utility
US 4,879,571 · App. 07/126,160
Duplex printing device
Inventor:
Paul E. Plasscheart
Patented Case
View Patent ↗
Granted: Nov 7, 1989
Filed: Nov 30, 1987
Inventor
Paul E. Plasscheart
Assignee (at issue)
Delphax Systems
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.