Granted Patent
Utility
US 4,616,934 · App. 06/668,290
Drum mix asphalt plant with knock-out box and separate coater
Inventor:
J. Donald Brock
Patented Case
View Patent ↗
Granted: Oct 14, 1986
Filed: Nov 5, 1984
Inventor
J. Donald Brock
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.