Granted Patent
Utility
US 4,867,572 · App. 07/307,176
Asphalt plant with fixed sleeve mixer
Inventors:
J. Don Brock, James G. May
Patented Case
View Patent ↗
Granted: Sep 19, 1989
Filed: Feb 3, 1989
Inventors
J. Don Brock
James G. May
Assignee (at issue)
Astec Industries, 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.