GB771433A - Improvements in rotary crushing machines - Google Patents

Abstract

771,433. Hammer mills. SMIDTH & CO. AKTIESELSKAB, F. L. Oct. 20, 1955 [Oct. 22, 1954]. No. 30028/55. Class 59 [Also in Groups VIII and XXX] Large blocks to be crushed are directed to a hammer rotor 10 by means of two or more resiliently-mounted rollers 8, 9 which are so disposed that the blocks are struck by the hammers 11 during the upward movement thereof above their axis of rotation, a guide plate 14 being spaced from the downward path of the path of the hammers to provide a space through which parts broken from the blocks must pass before leaving the mill, and in or at the entrance to which space they are subjected to further crushing by the hammers. The rollers are carried by shafts through the intermediary of rubber sleeves 13, and the roller 9 is grooved to resist backward movement of material. The blocks are fed to the rollers by means of a horizontal or inclined reciprocating feed table 3. Small pieces of material and those knocked off large blocks are thrown by the hammers against steel plates 17 to be further disintegrated. The crushed material passes through a grate 15 which, however, may be omitted. A curtain of drag chains 7 prevents any material flying back into the feed hopper 1. The hammer rotor is, driven independently of the rollers which may be replaced by an endless conveyer or by a push feeder similar to the feed table 3. The feed table may be replaced by a shoot or other device.