Patent ID: 8813967

Claim:
A classifier system for separating coarser particles from finer particles entrained in an upward air stream comprising: a housing having a general circular cross section; a truncated cone inside of the housing having a larger section at its top and a small cone outlet at its bottom, the cone defining an inner chamber; an outer chamber between the housing and the cone adapted to receive coarser and finer particles entrained in the upward air stream; a classifier ring at the top of the cone having a frame with a plurality of windows with vanes hinged adjacent to each window; wherein the vanes are adjustable to partially or fully close the windows thereby affecting the size of particles allowed through them and into the inner chamber; a fuel tube outlet above the classifier ring adapted to allow the air stream to exit the classifier system; and an adjustment system having: at least one pressure sensor upstream of the classifier ring to measure air pressure entering the classifier ring; at least one pressure sensor downstream of the classifier ring to measure air pressure exiting the classifier ring; a coarseness sensing device adapted to sense particle size exiting the fuel tube outlet; and, a control unit adapted to receive signals from the sensors and calculate a vane setting.