Improvements in or relating to Apparatus for Grinding or Crushing Foundry Sand or other similar Granular Material

10,152. Bonvillain, P. May 3. Casting.-An inclined hollow rotating cylinder a with loose rollers m for grinding foundry sand or other granular materials is mounted on rollers b and rotated by a pulley o formed around its centre. A bracket d at the lower end carries rollers e, against which the cylinder bears at its edges, while a plate f carried by the bracket d, and partially closing the cylinder end, prevents the crushing-rollers from passing out. A scraper g comprising a series of overlapping plates g' is carried by trunnions h, and is kept in contact with the upper surface of the cylinder a by a weight v at the end of a lever attached to the trunnion h. The material fed in at the upper end of the cylinder is first mixed and carried round by scoops a , to be deposited on an inclined plate a , which conducts the material to three parallel sets of crushing-rollers m of different diameters. In a modified form, the rollers may extend the whole length of the cylinder, the scoops a and the plate a being dispensed with, and the cylinder a may rest on pairs of rollers connected by shafts, which are actuated by bevel gearing from a main shaft, to rotate the cylinder. In this form, the scraper g is formed in one plate, with saw cuts forming comblike teeth at the scraping edge.