GB943450A - Ring mill with hydro-pneumatic springing - Google Patents

Abstract

943,450. Edge-runner mills. E. G. LOESCHE. Dec. 4, 1961 [Jan. 20, 1961], No. 43231/61. Heading B2A. A mill having grinding elements 25, 30, Fig: 1, rolling against one another comprises hydro-pneumatic, means 12 for pressing the elements against one another, the contact pressure of the grinding elements being transmitted through the piston rod 32 of a hydraulicallyactuated pressure cylinder 34 acting on one of the grinding elements. Four pressure cylinders may be provided connected by flexible pipes 36 to hydropneumatic accumulators 12 and a hydraulic pump 2, pipes 39 equalizing the pressure acting in the cylinders. The rods 32 of the pistons 33 of the cylinders are connected by levers 26, 28 to the grinding elements 25 which roll on a grinding ring 30 rotatable by a transmission 31 and the accumulators permit the rolls to lift from the ring when extraneous hard bodies reach the grinding surfaces. The cylinders 34 are mounted on pivots 35 and hydraulic pressure from the pump 2 and controlled by a valve 14 can be supplied to the lower ends of the cylinders to raise the rolls 25. The ring 30 may be raised hydraulically after the rolls have been raised to enable the transmission 31 to be removed for repair. The mill may be provided with means for sifting the material before it reaches the grinding elements and openings may be provided in the housing of the mill for the supply and discharge of air. In further embodiments, the rolls 50, shown on the lefthand side of Fig. 5, are pressed into contact with the grinding ring 30 by a pressure ring 52 bearing on steps 51 on the rolls and connected to the rods 32 of the pressure cylinders 34, and the rolls 54, shown on the right-hand side of Fig. 5, are pressed into contact with the grinding ring by a pressure ring 56 connected to the rods 32 and by arms 55 to the grinding rolls.