GB495225A - Improvements in device for crushing and pulverizing materials - Google Patents

Abstract

495,225. Impact pulverizers. UNIVERSITY PATENTS, Inc. Sept. 6,1937, No. 24313. Convention date, June 30. [Class 59] A pulverizer comprises an outer rotatable drum 11 and an inwardly extending drum 7 from which material is thrown by centrifugal force onto the inner surface of the outer drum. This material is removed by a scraper 24 and returned to the drum and the cycle repeated, the fines being withdrawn through an outlet 31. As shown the inner drum 7 is mounted on a rotatable shaft 6 driven by a pulley 8 and protrudes through the end of the drum 11 mounted on rollers 21 and rotated through gear ring 14 driven by a motor pinion. The discharge orifice 31 is inserted in the other end of the drum and has combined therewith a feed shoot 32. Two scrapers 24, 27, spaced apart and at different distances from the internal periphery of the drum remove material adhering by centrifugal force from the internal surface of the drum and discharge it into a hopper 25 from which it is fed by a shoot 26 to the drum 7. Material in the drum 7 is thrown through slots 23 onto the surface of the rotating drum 11 and builds up a protective layer on which the rest of the material is disintegrated. When the material spreads along the drum it is removed by the scrapers 24, 27 and is returned once more to the drum 7. Air is drawn through the gap between the end 17 of the drum and the periphery of the drum 7 and flows transversely across the material projected from the drum thereby entraining the pulverized particles to the discharge outlet 31. Additional air may enter through gap 41 in the end 18. In wet grinding water and material are fed through shoot 32 and adheres by centrifugal force to the sides of the drum 11 as shown in dotted lines 40. The ground material and water are discharged through gap 41.