Replaceable tip for a bit or auger bit

Abstract

A tool element for cutting a workpiece includes a shank adapted for connecting the tool element to a power tool, and a first cutting portion fixedly coupled to the shank and including a first cutting edge having a first diameter and a second cutting edge having a second diameter. A second cutting portion is removably coupled to the first cutting portion. The second cutting portion includes a third cutting edge having a third diameter and a fourth cutting edge having a fourth diameter. The second diameter is smaller than the first diameter, the third diameter is smaller than the second diameter, and the fourth diameter is smaller than the third diameter.

1 . A tool element for cutting a workpiece, the tool element comprising:
 a shank adapted for connecting the tool element to a power tool;   a first cutting portion fixedly coupled to the shank and including a first cutting edge having a first diameter and a second cutting edge having a second diameter; and   a second cutting portion removably coupled to the first cutting portion, the second cutting portion including a third cutting edge having a third diameter and a fourth cutting edge having a fourth diameter, wherein the second diameter is smaller than the first diameter, the third diameter is smaller than the second diameter, and the fourth diameter is smaller than the third diameter.   
     
     
         2 . The tool element of  claim 1 , wherein the shank extends from a first end of the first cutting portion and defines a central axis that extends toward a second end of the second cutting portion, and wherein the first cutting edge, the second cutting edge, the third cutting edge, and the fourth cutting edge are spaced apart from one another along the central axis between the shank and the second end. 
     
     
         3 . The tool element of  claim 2 , wherein first cutting edge is disposed adjacent the first end, the second cutting edge is disposed between the first cutting edge and the third cutting edge, the third cutting edge is disposed between the second cutting edge and the fourth cutting edge, and the fourth cutting edge is disposed adjacent the second end. 
     
     
         4 . The tool element of  claim 1 , further comprising a locking mechanism formed as part of the first cutting portion and the second cutting portion and operable to selectively inhibit movement of the second cutting portion with respect to the first cutting portion. 
     
     
         5 . The tool element of  claim 4 , wherein the locking mechanism includes a shaft fixedly coupled to one of the first cutting portion and the second cutting portion and an aperture formed as part of the other of the first cutting portion and the second cutting portion, the aperture sized to receive at least a portion of the shaft. 
     
     
         6 . The tool element of  claim 5 , wherein the shaft includes a portion having a non-circular cross section and the aperture includes a corresponding portion such that the shaft and the aperture cooperate to inhibit rotation of the first cutting portion with respect to the second cutting portion. 
     
     
         7 . The tool element of  claim 6 , wherein the shaft includes a portion having a polygonal cross section. 
     
     
         8 . The tool element of  claim 5 , wherein the locking mechanism includes a ball detent mechanism that selectively inhibits axial movement of the first cutting portion with respect to the second cutting portion. 
     
     
         9 . The tool element of  claim 5 , wherein the shaft is formed as part of the second cutting portion and the aperture is formed in the first cutting portion. 
     
     
         10 . The tool element of  claim 1 , wherein the shank defines a central axis, and wherein the first cutting edge and the second cutting edge are substantially parallel to the central axis. 
     
     
         11 . A tool element for cutting a workpiece, the tool element comprising:
 a first cutting portion including a first cutting edge having a first diameter, a second cutting edge having a second diameter, a shank extending from a first end of the first cutting portion to define a central axis, and an aperture formed along the central axis adjacent a second end of the first cutting portion;   a second cutting portion including a third cutting edge having a third diameter, a fourth cutting edge having a fourth diameter, and a shaft extending from the second cutting portion along the central axis; and   a locking mechanism formed as part of the aperture and the shaft to selectively couple the first cutting portion to the second cutting portion while inhibiting rotation and axial movement of the first cutting portion with respect to the second cutting portion along the central axis, wherein the first diameter, the second diameter, the third diameter, and the fourth diameter are not equal to one another.   
     
     
         12 . The tool element of  claim 11 , wherein the second diameter is smaller than the first diameter, the third diameter is smaller than the second diameter, and the fourth diameter is smaller than the third diameter. 
     
     
         13 . The tool element of  claim 11 , wherein the shaft includes a portion having a non-circular cross section and the aperture includes a corresponding portion such that the shaft and the aperture cooperate to inhibit rotation of the first cutting portion with respect to the second cutting portion. 
     
     
         14 . The tool element of  claim 13 , wherein the shaft includes a portion having a polygonal cross section. 
     
     
         15 . The tool element of  claim 11 , wherein the locking mechanism includes a ball detent mechanism that inhibits axial movement of the first cutting portion with respect to the second cutting portion. 
     
     
         16 . The tool element of  claim 11 , wherein the central axis extends toward a third end of the second cutting portion, and wherein the first cutting edge, the second cutting edge, the third cutting edge, and the fourth cutting edge are spaced apart from one another along the central axis between the shank and the third end. 
     
     
         17 . The tool element of  claim 16 , wherein first cutting edge is disposed adjacent the first end, the second cutting edge is disposed between the first cutting edge and the third cutting edge, the third cutting edge is disposed between the second cutting edge and the fourth cutting edge, and the fourth cutting edge is disposed adjacent the third end. 
     
     
         18 . The tool element of  claim 11 , wherein the first cutting edge and the second cutting edge are substantially parallel to the central axis. 
     
     
         19 . The tool element of  claim 18 , wherein the third cutting edge and the fourth cutting edge are substantially parallel to the central axis. 
     
     
         20 . A tool element for cutting a workpiece, the tool element comprising:
 a first cutting portion including a first cutting edge having a first diameter, a second cutting edge having a second diameter, a shank extending from a first end of the first cutting portion to define a central axis, and a polygonal aperture formed along the central axis adjacent a second end of the first cutting portion, the first cutting edge and the second cutting edge being substantially parallel to the central axis;   a second cutting portion including a third cutting edge having a third diameter, a fourth cutting edge having a fourth diameter, and a polygonal shaft extending from the second cutting portion along the central axis, the third cutting edge and the fourth cutting edge being substantially parallel to the central axis; and   a ball detent mechanism formed as part of the aperture and the shaft to selectively couple the first cutting portion to the second cutting portion while inhibiting rotation and axial movement of the first cutting portion with respect to the second cutting portion along the central axis, wherein the second diameter is smaller than the first diameter, the third diameter is smaller than the second diameter, and the fourth diameter is smaller than the third diameter.