Pick assembly, processing assembly comprising it, method of making it and method of using it

Abstract

A pick assembly comprising a holder body, a strike body, a base body attachable to a drive mechanism, and an interference assembly comprising at least one interference member. The holder body comprises a head portion and a shaft depending from the head portion. The strike body comprises a super-hard strike tip. The head portion and the strike body are cooperatively configured such that the strike body can be attached to the head portion, the strike tip being exposed for striking a body to be degraded when in use. The base body comprises a base bore. The base bore, shaft and interference assembly are cooperatively configured such that the shaft can be secured within the base bore, the interference member disposed between the shaft and the bore. Frictional interference between the shaft, interference assembly and base bore is sufficient to prevent rotation of the shaft within the base bore in use.

1 . A pick assembly comprising:
 a holder body,   a strike body,   a base body attachable to a drive mechanism, and   an interference assembly comprising at least one interference member;   in which:   the holder body comprises a head portion and a shaft depending from the head portion,   the strike body comprises a super-hard strike tip,   the head portion and the strike body are cooperatively configured such that the strike body can be attached to the head portion,   the base body comprises a base bore;   the base bore, shaft and interference assembly being cooperatively configured such that the shaft can be secured within the base bore, the interference member disposed between the shaft and the bore, frictional interference between the shaft, interference assembly and base bore being sufficient to prevent rotation of the shaft within the base bore in use.   
     
     
         2 . A pick assembly as claimed in  claim 1 , in which the combined radial margin of interference between the shaft, the interference member and the base bore is 10 to 200 microns. 
     
     
         3 . A pick assembly as claimed in  claim 1 , in which the interference member comprises a sleeve or ring configured to be capable of accommodating the shaft. 
     
     
         4 . (canceled) 
     
     
         5 . (canceled) 
     
     
         6 . (canceled) 
     
     
         7 . A pick assembly as claimed in  claim 1 , in which the strike body comprises polycrystalline diamond (PCD) material, or grains of synthetic or natural diamond dispersed in a matrix comprising carbide material. 
     
     
         8 . (canceled) 
     
     
         9 . (canceled) 
     
     
         10 . A pick assembly as claimed in  claim 1 , in which the shaft is coaxial with the strike body when the strike body is attached to the holder body as for use. 
     
     
         11 . A pick assembly as claimed in  claim 1 , in which the base bore comprises a cylindrical inner surface and has a diameter of 18.00 to 21.00 millimetres (mm). 
     
     
         12 . A pick assembly as claimed in  claim 1 , in which the base bore comprises a cylindrical inner surface, at least an area of the side of the shaft comprises a cylindrical surface, and the interference member comprises a resilient sleeve configured to be capable of accommodating the cylindrical area of the shaft and clamping it with sufficient compressive force that the shaft will not rotate relative to the sleeve in use, the thickness of the sleeve being 1.20 to 1.45 millimetres (mm). 
     
     
         13 . A pick assembly as claimed in  claim 1 , in which at least a portion of the shaft is cylindrical in shape and has a diameter of 16.00 to 19.00 millimetres (mm). 
     
     
         14 . A pick assembly as claimed in  claim 1 , in which the interference assembly comprises a spring sleeve and an interference member located between the spring sleeve and the base bore when assembled as for use. 
     
     
         15 . A pick assembly as claimed in  claim 1 , in which the interference member comprises elastomer material or other polymer material. 
     
     
         16 . A pick assembly as claimed in  claim 1 , in which the interference assembly comprises a laterally extending portion that will be located outside the base bore when assembled as for use, and which will be capable of protecting the base body in use. 
     
     
         17 . A pick assembly as claimed in  claim 1 , in which the interference member is in the form of an O-ring or quad-ring. 
     
     
         18 . A pick assembly as claimed in  claim 1 , in which the interference assembly is configured such that a portion of the shaft is spaced apart from the base bore, the portion and the base bore not being connected by solid state material. 
     
     
         19 . A pick assembly as claimed in  claim 1 , in which the interference assembly is configured such that a volume between the shaft and the base bore contains material from a body being degraded by means of the pick. 
     
     
         20 . (canceled) 
     
     
         21 . A pick assembly as claimed in  claim 1 , in which the interference assembly comprises a plurality of interference members. 
     
     
         22 . A processing assembly comprising a plurality of pick assemblies as claimed in  claim 1 , attachable to a drive mechanism. 
     
     
         23 . (canceled) 
     
     
         24 . A processing assembly as claimed in  claim 16 , suitable for pavement scarifying. 
     
     
         25 . A processing assembly as claimed in  claim 16 , in which each of the shafts of all of the pick assemblies have the same diameter and the dimensions of the respective interference members differ from each other to compensate for differences in at least one base bore dimension. 
     
     
         26 . (canceled) 
     
     
         27 . (canceled) 
     
     
         28 . A method of making a pick assembly as claimed in  claim 1 , the method including:
 providing a first pick assembly comprising   a first holder body and   a base body, attachable to a drive mechanism, and   a rotation member;   in which the first holder body comprises a first shaft and the base body comprises a base bore;   the base bore, the first shaft and the rotation member being cooperatively configured such that the first shaft can be inserted within the base bore, the rotation member   being disposed between the first shaft and the base bore, such that the first shaft will be capable of rotation relative to the base bore when in use;   removing the rotation member and the first holder body;   providing a second holder body and an interference assembly comprising an interference member; in which   the second holder body comprises a head portion and a second shaft depending from the head portion,   the head portion and a strike body being cooperatively configured such that the strike body can be attached to the head portion,   the strike body comprising a super-hard strike tip;   the second shaft and interference assembly being cooperatively configured such that the second shaft can be secured within the base bore, the interference member disposed between the second shaft and the bore, frictional interference between the second shaft, interference assembly and base bore being sufficient to prevent rotation of the second shaft within the base bore in use;   the pick assembly comprising the base body, the second holder body, the strike tip and the interference member.   
     
     
         29 . (canceled) 
     
     
         30 . (canceled) 
     
     
         31 . A method of using a processing assembly as claimed in  claim 19 , the method including striking a work body by an end of the strike body coterminous with the super-hard material and removing material from the work body to provide a corresponding plurality of grooves, each having a depth of at most  15  centimetres (cm). 
     
     
         32 . (canceled) 
     
     
         33 . A method as claimed in  claim 20 , in which the body to be degraded comprises any of pavement, concrete or asphalt.