Method and apparatus for pneumatically classifying solids

Claim 1

IN A PNEUMATIC CLASSIFIER, A PLURALITY OF SUPERPOSED WIND CHAMBERS DISPOSED IN SPACED RELATIONSHIP, COMMON MEANS FOR PASSING AIR-STREAMS IN PARALLEL, RESPECTIVELY THROUGH SAID WIND CHAMBERS, A HOPPER MEANS FOR CONTAINING A PLURALITY OF PARTICLES OF DIVERSE SIZE AND HAVING DISCHARGE MEANS FOR DROPPING A STREAM OF DIVERSE PARTICLES IN FREE FALL DIRECTLY AND GENERALLY TRANSVERSELY THROUGH THE AIR-STREAM OF THE FIRST WIND CHAMBER FOR INITIAL PNEUMATIC CLASSIFICATION OF THE DIVERSE PARTICLES THEREIN IN A PLURALITY OF FRACTIONS IN THE DIRECTION OF THE AIR-STREAMS, A FIRST ROW OF COLLECTORS IN THE FIRST WIND CHAMBER SPACED FROM THE DISCHARGE MEANS OF SAID HOPPER FOR SEPARATELY COLLECTING INDIVIDUAL FRACTIONS OF THE CLASSIFIED PARTICLES, SAID COLLECTORS, EACH INCLUDING A COLLECTING AND DISCHARGE MEANS FOR COLLECTING AN INDIVIDUAL FRACTION OF THE FALLING PARTICLES IN THE DIRECTION OF AIR FLOW TO RETURN THEIR VELOCITIES TO SUBSTANTIALLY ZERO AND TO DROP EACH OF THE COLLECTED PARTICLE FRACTIONS IN A ROW OF ADJACENT STREAMS OF PARTICLES IN THE ORDER IN WHICH COLLECTED IN GENERALLY FREE TRANSVERSE FALL THROUGH THE AIR-STREAM OF THE WIND CHAMBER NEXT ADJACENT THE FIRST WIND CHAMBER FOR A PARTIAL RECLASSIFICATION IN A SECOND ROW OF PARTICLE COLLECTORS SPACEE FROM THE FIRST ROW OF PARTICLE COLLECTORS, COLLECTING MEANS IN THE SECOND PARTICLE COLLECTORS BEING DISPOSED ADJACENT TO EACH OTHER FOR RECEIPT OF PARTIALLY RECLASSIFIED STREAMS OF PARTICLES FROM SAID FIRST ROW OF COLLECTORS AND MEANS FOR REMOVING CLASSIFIED PARTICLES FROM SAID SECOND COLLECTOR.