Granted Patent
Utility
US 4,429,647 · App. 06/445,661
Method of and device for loosening agriculturally used soil
Inventor:
Eugen Zinck
Patented Case
View Patent ↗
Granted: Feb 7, 1984
Filed: Nov 30, 1982
Inventor
Eugen Zinck
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.