Polygon-shaped carbide tool pick

Abstract

A polygonal tool pick formed entirely of a single hard material, including a head, a shoulder extending rearwardly from the head and having an outer dimension at least as large as a largest outer dimension of the head, a shank extending rearwardly from the shoulder and having an outer dimension smaller than the outside dimension of the shoulder, and a tail extending rearwardly from the shank and having an outer dimension larger than the outer dimension of the shank, wherein the head, the shoulder, the shank, and the tail each have a plurality of faces with at least one pair of opposed faces being parallel to each other.

1 . A polygonal tool pick formed entirely of a single hard material, the tool pick comprising:
 a head;   a shoulder extending rearwardly from the head and having an outer dimension at least as large as a largest outer dimension of the head;   a shank extending rearwardly from the shoulder and having an outer dimension smaller than the outside dimension of the shoulder; and   a tail extending rearwardly from the shank and having an outer dimension larger than the outer dimension of the shank;   wherein the head, the shoulder, the shank, and the tail each have a plurality of faces with at least one pair of opposed faces being parallel to each other.   
     
     
         2 . The polygonal tool pick of  claim 1 , wherein the number of faces is an even number. 
     
     
         3 . The polygonal tool pick of  claim 1 , wherein all of the faces are of equal size. 
     
     
         4 . The polygonal tool pick of  claim 2 , wherein the number of faces is at least four. 
     
     
         5 . The polygonal tool pick of  claim 4 , wherein the number of faces is eight. 
     
     
         6 . The polygonal tool pick of  claim 1 , wherein the single hard material is cemented carbide. 
     
     
         7 . The polygonal tool pick of  claim 1 , the head comprising:
 a pyramidal cutting tip terminating in a frontward tip end; and   a truncated pyramidal base supporting the cutting tip and disposed rearwardly with respect to the cutting tip, the pyramidal cutting tip having a steeper slope than the truncated pyramidal base with respect to an axis of the tool pick.   
     
     
         8 . The polygonal tool pick of  claim 7 , wherein the pyramidal cutting tip has a slope of about 30° to about 60° and the truncated pyramidal base has a slope of about 5° to about 30°. 
     
     
         9 . The polygonal tool pick of  claim 1 , further comprising a tapered frontward seat located between the shoulder and the shank, the seat being tapered from a smaller outer dimension at a junction with the shank to a larger outer dimension at a junction with the shoulder. 
     
     
         10 . The polygonal tool pick of  claim 1 , further comprising a tapered rearward seat located between the tail and the shank, the seat being tapered from a smaller outer dimension at a junction with the shank to a larger outer dimension at a junction with the tail. 
     
     
         11 . A polygonal tool pick formed entirely of cemented carbide, the tool pick comprising:
 a pyramidal cutting tip terminating in a frontward tip end, the cutting tip having an even number of equally sized faces;   a truncated pyramidal base supporting the cutting tip and disposed rearwardly with respect to the cutting tip, the truncated pyramidal base having a shallower slope than the pyramidal cutting tip with respect to an axis of the tool pick, the base having an even number of equally sized faces aligned with the faces of the cutting tip;   a shoulder extending rearwardly from the head and having an outer dimension at least as large as a largest outer dimension of the base, the shoulder having an even number of equally sized faces aligned with the faces of the base;   a shank extending rearwardly from the shoulder and having an outer dimension smaller than the outside dimension of the shoulder, the shank having an even number of equally sized faces aligned with the faces of the shoulder;   a tapered frontward seat located between the shoulder and the shank, the seat being tapered from a smaller outer dimension at a junction with the shank to a larger outer dimension at a junction with the shoulder, the frontward seat having an even number of equally sized faces aligned with the faces of the shank;   a tail extending rearwardly from the shank and having an outer dimension larger than the outer dimension of the shank, the tail having an even number of equally sized faces aligned with the faces of the shank; and   a tapered rearward seat located between the tail and the shank, the seat being tapered from a smaller outer dimension at a junction with the shank to a larger outer dimension at a junction with the tail, the rearward seat having an even number of equally sized faces aligned with the faces of the shank.   
     
     
         12 . The polygonal tool pick of  claim 11 , wherein the number of faces of each of the cutting tip, the base, the shoulder, the shank, the frontward seat, the rearward seat, and the tail is eight. 
     
     
         13 . A pick assembly comprising:
 a holder having a cylindrical bore;   a polygonal tool pick formed entirely of cemented carbide, the tool pick comprising:
 a pyramidal cutting tip terminating in a frontward tip end; 
 a truncated pyramidal base supporting the cutting tip and disposed rearwardly with respect to the cutting tip, the truncated pyramidal base having a shallower slope than the pyramidal cutting tip with respect to an axis of the tool pick; 
 a shoulder extending rearwardly from the base and having an outer dimension at least as large as a largest outer dimension of the base; 
 a shank extending rearwardly from the shoulder and having an outer dimension smaller than the outer dimension of the shoulder; and 
 a tail extending rearwardly from the shank and having an outer dimension larger than the outer dimension of the shank; 
   wherein the cutting tip, the base, the shoulder, the shank, and the tail each have an even number of faces with at least one pair of opposed faces being parallel to each other, the faces of each of the cutting tip, the base, the shoulder, the shank, and the tail being aligned; and   a compressible cylindrical retainer for holding the tool pick within the cylindrical bore of the holder, such that when the retainer is compressed, the retainer is located between the shank and the cylindrical bore, and the inner diameter of the compressed retainer is less than the outer dimension of the tail and the outer dimension of the shoulder.   
     
     
         14 . A microtrenching wheel having a disk and a plurality of pick assemblies mounted around the circumference of the disk, each pick assembly comprising:
 a holder having a cylindrical bore;   a polygonal tool pick formed entirely of cemented carbide, the tool pick comprising:
 a pyramidal cutting tip terminating in a frontward tip end; 
 a truncated pyramidal base supporting the cutting tip and disposed rearwardly with respect to the cutting tip, the truncated pyramidal base having a shallower slope than the pyramidal cutting tip with respect to an axis of the tool pick; 
 a shoulder extending rearwardly from the base and having an outer dimension at least as large as a largest outer dimension of the base; 
 a shank extending rearwardly from the shoulder and having an outer dimension smaller than the outer dimension of the shoulder; and 
 a tail extending rearwardly from the shank and having an outer dimension larger than the outer dimension of the shank; 
   wherein the cutting tip, the base, the shoulder, the shank, and the tail each have an even number of faces with at least one pair of opposed faces being parallel to each other, the faces of each of the cutting tip, the base, the shoulder, the shank, and the tail being aligned; and   a compressible cylindrical retainer for holding the tool pick within the cylindrical bore of the holder, such that when the retainer is compressed, the retainer is located between the shank and the cylindrical bore, and the inner diameter of the compressed retainer is less than the outer dimension of the tail and the outer dimension of the shoulder.