GB683849A - Improvements in or relating to centrifugal mills - Google Patents

Abstract

683,849. Impact pulverizers. KLAGSBRUNN, J., and MARKUS, E. Oct. 2,1950. [Oct. 7, 1949], No. 24074/50. Class 59 A centrifugal mill, Fig. 1, comprising stationary comminuting sections 1, 2 having chambers d<SP>1</SP>, d<SP>2</SP> into which the material to be reduced is thrown by members c carried by a rotor b, has a regulateable current of air for conveying the comminuted material from the mill, each chamber being formed with a spirally-curved inner wall serving to curl the stream of air and material back upon itself, Fig. 6, to intersect the incoming material at a point m inside the chamber so as to cause comminuting by friction at the point m and at the walls of the chamber. Material is fed through a shoot a, Fig. 1, to the members c which are clamped in adjusted position on the rotor b by bolts so that they are still capable of rotation on the bolts should excessive resistance be encountered. A centrifugal fan h sucks the material between the plurality of sections 1, 2 and then through a labyrinth formed by conical or cylindrical annuli f<SP>1</SP>, f<SP>2</SP> before discharging it through the fan section 3 which can be adjusted angularly to align with a screening device or separator. The flow of air through the sections 1, 2, and consequently the fineness of the ground material, is controlled by an iris shutter f in an opening g to the fan h. A jacket i may be provided for water cooling. When more than two sections 1, 2 are employed, the chambers in the last compartment may be replaced by a perforated sheet through which the comminuted material is sucked to withdraw it from the mill. In a modification, Fig. 4, the fan and a separator are connected to the iris passage g by pipes l<SP>1</SP>, l<SP>2</SP>, l<SP>3</SP>, l<SP>4</SP>. Each compartment may be formed from segments, Fig. 6, held together by springs r so that when a key has been removed from a recess s the ring of segments may be opened out to extend the chambers d<SP>1</SP> so that they may be cleaned without removing the springs r. Grooves n are formed in the bottom walls of the chambers.