Granted Patent
Utility
US 4,971,694 · App. 07/293,855
Double diffuser with backflush pistons
Inventor:
Ole J. Richter
Patented Case
View Patent ↗
Granted: Nov 20, 1990
Filed: Jan 5, 1989
Inventor
Ole J. Richter
Assignee (at issue)
Kamyr AB
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.