GB467196A - Improvements in grinding mills - Google Patents

Abstract

467,196. Disc mills; stuffing-box substitutes. PREISS, M. Dec. 12, 1935, No. 34459. [A Specification was laid open to inspection under Sect. 91 of the Acts, June 18, 1936.] [Class 59] [Also in Group XXVI] In a disc mill cooling devices for gaseous or liquid medium conduct the medium over the outer surfaces of the discs, through gaps in the discs to the teeth and through the delivery passage for the ground material into the atmosphere. As shown in Fig. 1, air is drawn through an inlet 12, controlled by a valve 50, by a fan 4 on the back of the rotating disc 1. The fan blades are provided with slots 14 at their point of connection with the disc to allow air to spread over the whole surface of the back of the disc. Part of the air passes through a passage 8 to the centre of the discs and enters with the feed from hopper 9 which is prevented from entering the passage 8 by a leather &c. extension from the part 7. The air flow through the passage 8 is controlled by an adjustable flap 15 and additional air may be let in through plug 19. The remaining part of the air is driven by the fan through the outlet 13. The fixed disc 2 is water-cooled and air from a pipe 17 is inserted by nozzle 29 into a gap in the discs. The lefthand side, Fig. 3, shows a water pipe 25 and spray nozzle 24 for cooling the back of the rotating disc, the disc being provided with a flange 38 and sealing means 23, a stripper member 41 deflecting the water to the outlet 26. In a modification shown on the right-hand side of Fig. 3, air from a removable nozzle 28 is drawn in over the bearing of the rotating disc before passing to the back of the disc. The fixed disc 2 is formed with a water chamber 11 and cooling air is supplied to the teeth by jets 29, 31 from a spiral pipe 17. In Fig. 5 the stripper member comprises a rubber ring 44 on the rotary disc and a curved rubber ring 45 on the casing 5, the water being deflected from the rotary disc as shown by the arrows. The teeth on the discs, Fig. 7, are of tapered sections along their length so that in one direction of rotation a cutting action occurs with the large end A and in the other direction of rotation a crushing or bruising action takes place.