Mineral cutter system

Abstract

A mineral cutter system comprises a pick box ( 3 ) adapted to be secured, by welding, to a powered drum or disc ( 2 ) and having a bore ( 4 ) to receive a replaceable sleeve ( 5 ) having a collar ( 8 ) and also a circular section bore ( 15 ) to receive a circular section shank ( 16 A or 16 B) of a replaceable mineral cutter pick ( 17 A or 17 B), the bore ( 4 ) of the pick box ( 3 ) incorporating at least one flat ( 6 ), and the sleeve ( 5 ) being provided with at least one external flat ( 7 ) to engage the flat ( 6 ) whereby the sleeve ( 5 ) is non-rotatable with respect to the box ( 3 ), and the collar ( 8 ) of the sleeve ( 5 ) being both recessed (at 21 ) to accommodate a circular collar ( 20 ) of a point attack pick ( 17 A), and slotted to provide opposed abutment faces ( 23 ) to engage a pair of opposed flats ( 27 ) of a non-rotatable, semi-forward attack pick ( 17 B). The invention also includes a rotary drum or disc ( 1 ) provided with this cutter system and with either a rotatable or non-rotatable pick ( 17 A or 17 B).

1 . A mineral cutter system comprising a pick box adapted to be secured, by welding, to a powered drum or disc and having a bore to receive a replaceable sleeve having a collar to limit penetration of said sleeve into said bore of said pick box, said sleeve having a circular section bore to receive a circular section shank of a replaceable mineral cutter pick, characterised in that said bore of said pick box incorporates at least one flat, and said sleeve is provided with at least one external flat adapted, when fitted into said bore of said pick box, to engage said flat of said bore, whereby said sleeve is non-rotatable with respect to said box, and said collar of said sleeve is both recessed to accommodate a circular collar of a point attack pick, and slotted to provide opposed abutment faces to engage a pair of opposed flats of a non-rotatable, semi-forward attack pick. 
   
   
       2 . A system as claimed in  claim 1 , wherein said bore of said pick box is provided with two, four, six or eight opposed flats. 
   
   
       3 . A system as claimed in  claim 2 , wherein said sleeve is provided with a corresponding number of flats to that of said bore. 
   
   
       4 . A system as claimed in  claim 1 , wherein said sleeve is provided with a circumferential groove to receive a retaining device to engage said bore of said pick box to prevent inadvertent extraction of said sleeve from its receiving bore. 
   
   
       5 . A system as claimed in  claim 4 , wherein said retaining device is of synthetic plastics. 
   
   
       6 . A system as claimed in  claim 4 , wherein said retaining device is provided with multiple deformable ribs. 
   
   
       7 . A system as claimed in  claim 1 , wherein said shank of said pick, whether point attack or semi-forward attack, is provided with a retaining device. 
   
   
       8 . A system as claimed in  claim 7 , wherein said retaining device of said shank is a spring steel, split ring. 
   
   
       9 . A system as claimed in  claim 1 , wherein an end of said pick box remote from said collar of said sleeve is open to expose an end of said sleeve and an end of a pick, with tolerances between said bore of said pick box and said sleeve, and between said bore of said sleeve and said pick shank, being such that a worn pick may be knocked out of said sleeve, and a worn sleeve may be knocked out of said pick box. 
   
   
       11 . A rotary drum or disc provided with a plurality of pick boxes, secured by welding, to its external periphery, each said pick box having a bore in which is fitted a replaceable sleeve having a collar to limit penetration of said sleeve into said bore of said pick box, said sleeve having a circular section bore in which is fitted a circular section shank of a replaceable mineral cutter pick, said bore of said pick box incorporating at least one flat, and said sleeve being provided with at least one external flat adapted, to engage said flat of said bore, whereby said sleeve is non-rotatable with respect to said box, and said collar of said sleeve is recessed and accommodates a circular collar of a point attack pick. 
   
   
       12 . A rotary drum or disc provided with a plurality of pick boxes, secured by welding, to its external periphery, each said pick box having a bore in which is fitted a replaceable sleeve having a collar to limit penetration of said sleeve into said bore of said pick box, said sleeve having a circular section bore in which is fitted a circular section shank of a replaceable mineral cutter pick, said bore of said pick box incorporating at least one flat, and said sleeve being provided with at least one external flat adapted, to engage said flat of said bore, whereby said sleeve is non-rotatable with respect to said box, and said collar of said sleeve is slotted to provide opposed abutment faces to engage a pair of opposed flats of a non-rotatable, semi-forward attack pick.