Granted Patent
Utility
US 4,889,428 · App. 06/760,046
Rotary mill
Inventor:
Harry Hodson
Patented Case
View Patent ↗
Granted: Dec 26, 1989
Filed: Jul 29, 1985
Inventor
Harry Hodson
Assignee (at issue)
Concrete Technology, Inc.
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.