Impact mill

The feasibility of impact mills was greatly enhanced by the mechanization and engineering of the Industrial Revolution.

Prior to the industrial revolution, milling was primarily done by attrition or grinding the material between two surfaces.

[2] This is accomplished by a cascading motion of larger pieces repetitively impacting and compressively grinding the product into finer particles as it rotates in the chamber.

Dynamic impact would occur when material is dropped into a chamber where it receives a pulverizing blow from a hammer, rotor or pin.

[3] Pulverizing can be enhanced by engineering the rotor or hammer[4] to pass close to a serrated fixed stator.

Diagram of an impact mill.