Abstract: An impact mill including a base portion on which is disposed a rotor rotatably mounted in a bearing housing, the rotor having an upwardly aligned cylindrical surface portion coaxial with the rotational axis. The impact mill is provided with a mill casing within which is located a conical track assembly which surrounds the rotor to form a conical grinding path. The mill casing is provided with a downwardly aligned cylindrical collar which may be axially adjusted to set a grinding gap between the rotor and the mill casing. The rotor is provided with a plurality of impact knives complementary with a plurality of impact knives disposed on the inside top surface of the mill casing. In addition, the impact mill can be formed of separated conical sections. Finally, power is transmitted to the rotor of the impact mill by a synchronous sprocketed belt, accommodated by a sprocketed drive sheave, wherein the belt is in communication with a power source.

Abstract: An impact mill including a base portion on which is disposed a rotor rotatably mounted in a bearing housing, the rotor having an upwardly aligned cylindrical surface portion coaxial with the rotational axis. The impact mill is provided with a mill casing within which is located a conical track assembly which surrounds the rotor to form a conical grinding path. The mill casing is provided with a downwardly aligned cylindrical collar which may be axially adjusted to set a grinding gap between the rotor and the mill casing. The rotor is provided with a plurality of impact knives complementary with a plurality of impact knives disposed on the inside top surface of the mill casing. The conical track assembly can be a series of assembled conical sections or one unit with varied number of serrations in either a vertical or sloped configuration. This flexibility allows for greater compatibility with the feedstock being milled.

Abstract: A process and apparatus for comminuting rubber particles. In this process and apparatus rubber particles at a temperature below the glass transition temperature are introduced into a comminuting device concurrent with the introduction of an inert gas coolant at a temperature below about ?75° F. The rubber particles are comminuted in the comminuting device at a rate proportional to the average particle size of the introduced rubber particles to an average size within the range of crumb or powder rubber particles.