GB373532A - Improvements in roller mills - Google Patents

Abstract

373,532. Roller and roller-and-ring mills; conical mills. KNUPFFER, P. VON, 2, Canovastrasse, Friedenau, Berlin. Oct. 24, 1931, No. 29578. [Class 59.] In a roller mill for grinding corn, metal foil, &c. one or more of the rolls is as a whole of resilient construction. The rolls 2, retained in cages 19, Fig. 1, are constructed as helical springs which are pressed into contact with a central driven roller 1 by wedges 5, Fig. 2, bearing on the external casing 4. Spacing strips are inserted between the wedges which thus form cutting edges with the springs. The grain &c. enters at 22 and the ground material is carried out by an air blast which enters at 18 and leaves at 17. The springs may have a right- and left-hand helix to prevent axial thrust or they may be conical or tapered towards each end. The abutting edges of the spring are rounded or tapered to prevent any self-grinding action between the coils. The centre roller I may have a helical groove on its surface or be surrounded by a spring. The grinding surface of the spring may be grooved transversely or provided with cross-shaped grooves. The pressure of the rollers may be adjusted by the movement of a tapered liner 7, Fig. 18, on which they bear or the mill casing may be made in sections which can be drawn together by bolts, or the centre roller may be expanded. The liners may be grooved or perforated for the passage of the air blast or the abutting edges of the springs may be grooved, and these grooves may be engaged by spikes or teeth on the central roller to ensure positive revolution of the spring roller. Two mills may be combined as shown in Fig. 18, the ground material from the central mill falling on to a screw thread 23 on the inside of the roller 24 of the outer mill by which it is conveyed to the outer mill rollers, the air blast being arranged in parallel or series through the mills.