Patent ID: 7665681
Filing Date: 2010-02-23
Classification: B02C

Abstract:
1. A roller mill for pulverizing material; said roller mill comprising: an input chute adapted, to receive said material; a mill connected to the input chute, adapted to receive said material from the input chute, the mill including a grinding mechanism of at least one grinding roll and grinding ring that coact to pulverize said material prior to other processing of said material within a mill housing that defines a grinding chamber, the pulverized material being released into an air stream to creating particle-laden air; a classifier adapted to receive the particle-laden air from the mill, the classifier including a rotor having a plurality of blades disposed within a classifier housing defining a classifying chamber, where the rotor rotates to separate fine sized particles from oversized particles, whereby the finer sized particles pass through the blades and exit the classifier and the oversized particles are propelled outward against the classifier housing, the grinding chamber being in fluid communication with the classifying chamber; and a baffle disposed along the inner periphery of the mill housing spaced at least a constant distance from the mill housing as the baffle extends downward to provide an inner passage and an outer annular passage that does not converge as it extends downward, the inner passage being a generally open space for directing the particle-laden air upward through the grinding chamber to the classifier, the outer annular passage receiving and directing the oversized particles downward to the grinding mechanism of the mill such that the baffle minimizes upward forces created by airflow on the oversized particles, the baffle having an opening at the bottom of the outer annular passage for directing the oversized particles to the grinding mechanism.