Granted Patent
Utility
US 5,137,091 · App. 07/539,809
Process of producing molded body from green molding sand
Inventor:
Heinz Duster
Patented Case
View Patent ↗
Granted: Aug 11, 1992
Filed: Jun 18, 1990
Inventor
Heinz Duster
Assignee (at issue)
Goerg Fischer AG
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.