GB809789A - Improvements in apparatus for drying or roasting, and reducing or comminuting materials - Google Patents

Abstract

809,789. Comminuting apparatus. ARSAN, N. T. July 15, 1955 [July 18, 1954], No. 20573/55. Class 59 [Also in Groups I and XIII]. Apparatus for drying and comminuting materials comprises a drying unit located at the upper part of a supporting structure and a comminuting unit fixed to the supporting structure and located within an upright cylindrical casing below the drying unit to receive treated material therefrom, the comminuting unit having means for reducing the material in a plurality of stages one of which is formed by a grinding mill comprising opposed grinding members or assemblies of grinding members mounted within the casing for rotation relative to each other, each grinding member or assembly of grinding members having or forming a series of annular ribs with an annular groove or grooves therebetween and the or each groove between the ribs of a member or assembly of members being opposed to a rib of the opposing member or assembly of members. As shown in Fig. 1, material dried in a heated chamber 3 flows to a grinding unit comprising a casing 9 having therewithin a screw 10 secured to a grinding member 11 having tapered annular ribs co-operable with similar ribs in a grinding member 14, the members 11 and 14 being rotatable in opposite directions, preferably at different speeds. The chamber 3 and the grinding unit are supported by pillars 16 to 19. In a modification, Fig. 4, the grinding. unit comprises, a screw 62 secured to a grinding member 63 having an undulating surface forming ribs 63A provided with knives or blades 65 co-operable with similar knives or blades provided on grooves 64A formed by the undulating surface of a grinding member 64, the members 63, 64 being rotatable in opposite directions. In a further modification, Fig. 5, the grinding unit comprises two sets of reducing means, one set comprising knives or blades 85 fixed to the casing of the unit cooperating with knives or blades 88 fixed to a cylinder 91 and a grinding disc 86 fixed to the casing co-operating with grinding discs 89 fixed to the cylinder 91, and the second set comprising grinding discs 87 fixed to the casing co-operating with grinding discs 90 fixed to the cylinder 91, the cylinder 91 and the casing being rotatable in opposite directions. A stirrer 92 and sieve 93 separate out fine material from the first set of reducing means.