Granted Patent
Utility
US 4,452,694 · App. 06/202,101
Apparatus for selective sorting of material chips
Inventors:
Elmer Christensen, Frank J. Steffes
Patented Case
View Patent ↗
Granted: Jun 5, 1984
Filed: Oct 30, 1980
Inventors
Elmer Christensen
Frank J. Steffes
Assignee (at issue)
Black Clawson Company, 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.