Impeller assembly for an impact crusher

Claim 1

An impeller assembly for use in a centrifugal impact rock crusher, comprising: a rotatable cylindrical impeller housing with a vertically disposed central rotary axis, said housing having an upper impeller unit which has a feed opening disposed coaxially with said housing for receiving rock, said housing also having a lower impeller unit which has a landing surface disposed coaxially with said housing for ipingement on said landing surface of rock being fed through said feed opening, said impeller units being connected to each other by a generally cylindrical side wall unit which has a plurality of exit openings spaced around said side wall unit, each of said exit openings having an upper opening edge, a bottom opening edge, and two opposing side opening edges, wherein rotation of the impeller housing about said axis defines one of said side opening edges of each of said exit openings of each of said exit openings as a forward side edge and the other of said side edges as a rearward side edge with respect to the direction of rotation of the impeller housing; lip means including a plurality of removable lip providing members disposed within respective of said exit openings and being disposed adjacently the rearward side edge thereof, each of said lip members having first and second ends spaced apart circumferentially around said side wall unit, and each of said lip members being formed with a generally right-angle bend near said first end, a curved bend near said second end and directed oppositely to said generally right-angle bend, and a central portion between said generally right-angle bend and curved bend said generally right-angle bend defining a lip portion adjacent said first end, said lip portion having inner and outer lip surfaces with respect to bend, said generally right angle said inner lip surfaces extending substantially the full height of a respective exit opening and being directed generally inwardly with respect to said cylindrical side wall unit for facilitating retention of a portion of rock to be crushed to thereby protect the rearward side edge of each exit opening, and an outer surface of said central portion being placed adjacently the rearward side edge of it respective opening; and retaining means for each lip providing member, said retaiing means including said curved bend ad a vertical column attached between said upper and lower impeller units near said side wall unit and partially surrounded and engaged by the curved bend of the lip member.