US Patent 10322487 Roller mill grinding apparatus with regenerative capability

A roll grinding apparatus may comprise a frame, first and second rolls rotatably mounted on the frame in proximity to each other to grind materials passing between the rolls, and first and second motors to rotate the first and second rolls respectively. A control apparatus controls operation of at least one of the motors. The control apparatus may be configured to control the speed of the second roll by providing power to the second motor or braking the second motor through regeneration of energy from the second motor.