Abstract: In a rotary mineral crusher a method of either localising the wear on a weir tip (1) in the crusher and/or focusing the output of the rotor (7) into its interaction chamber and/or reducing mineral erosion of the exterior of the rotor (7) by mineral piece particles energised by the output from the rotor (7). The rotary mineral crusher is of a kind having a rotor (7) into which the mineral pieces to be reduced in size, that is crushed, are fed from above and least substantially axially over the axis of rotation of the rotor (7) to thereafter migrate on an acceleration locus or loci of migration there retained bed or retained beds of mineral pieces from the rotor (7) substantially radially of the rotor (7) into the surrounding interaction chamber capable of retaining the lining of the mineral material.

Abstract: A rotary mineral breaker of the type having a rotor (1) able to rotate about a substantially vertical axis. The rotor has an inlet for mineral pieces which are to be broken. The inlet is substantially parallel to the rotary axis when viewed from above. The rotor also has at least one peripheral exit port (9) for such materials, that is minerals after breaking, to exit radially of the rotor into a surrounding mineral material interaction zone (6). The rotor has a feature that at the or each peripheral port, but carried by the said rotor, there is means providing an exit port geometry which at least includes a mineral piece there to accumulation weir (3) to encourage by the appropriate profiling of the bed, those mineral pieces accelerating, in use, on the bed of retained mineral pieces (5) to exit over the weir (3) away from the upper regions of the retained bed (5).