Cutting Elements with Ridged and Inclined Cutting Face

Abstract

A drill bit for cutting formation comprises a bit body, a plurality of cutters, and a plurality of blades with pockets to accommodate the cutters, respectively. Each of the plurality of cutters has a substrate, an ultra-hard layer, an inclined surface on the top of the ultra-hard layer, wherein the inclined surface slants downward from a cutting edge to a trailing edge. The cutter can improve cutting efficiency and service life.

What is claimed is: 
     
         1 . A cutter comprising
 a substrate;   an ultra-hard layer;   an inclined surface on top of the ultra-hard layer; and   wherein the inclined surface slants downward from a cutting edge to a trailing edge.   
     
     
         2 . The cutter of  claim 1 , further comprising a chamfer extending from a periphery of the inclined surface to the cutting edge at a side wall of the ultra-hard layer. 
     
     
         3 . The cutter of  claim 1 , wherein the inclined surface comprises a cutting ridge extending from the cutting edge to the trailing edge diametrically on top of the inclined surface and two side surfaces slanting downward respectively from the cutting ridge to a periphery of the inclined surface. 
     
     
         4 . The cutter of  claim 3 , wherein a profile angle at the trailing edge is larger than a profile angle at the cutting edge. 
     
     
         5 . The cutter of  claim 3 , wherein the cutting ridge is a round cutting ridge. 
     
     
         6 . The cutter of  claim 1 , wherein the cutter height at the cutting edge is taller than the cutter height at the trailing edge. 
     
     
         7 . The cutter of  claim 1 , wherein the inclined surface comprises two cutting ridges intersecting at a cutting point on the cutting edge and extending from the cutting point to the trailing edge. 
     
     
         8 . The cutter of  claim 7 , wherein the two cutting ridges separate the inclined surface into two side flat surfaces and a central flat surface; wherein the two side flat surfaces slant downward from the two cutting ridges to a periphery of the inclined surface; and wherein the central flat surface slants downward from the cutting edge to the trailing edge. 
     
     
         9 . The cutter of  claim 7 , wherein the two cutting ridges separate the inclined surface into concave or convex surfaces. 
     
     
         10 . The cutter of  claim 1 , wherein the inclined surface comprises two converging ridges and a central cutting ridge intersecting at a point away from the cutting edge, and the two converging ridges and the central cutting ridge divide the inclined surface into two side surfaces and one central surface. 
     
     
         11 . The cutter of  claim 10 , wherein the two side surfaces are flat and the one central surface is flat. 
     
     
         12 . The cutter of  claim 10 , wherein the two side surfaces intersect at the central cutting ridge and the two side surfaces intersect the central surface at the two converging ridges. 
     
     
         13 . The cutter of  claim 10 , wherein the two cutting ridges separate the inclined surface into concave or convex surfaces. 
     
     
         14 . The cutter of  claim 10 , wherein an outer end of the central cutting ridge meets the cutting edge at a cutting point; wherein the central cutting ridge is parallel to a cutter bottom surface of the substrate; and wherein the central surface has an inclination toward the trailing edge. 
     
     
         15 . The cutter of  claim 10 , wherein the central cutting ridge is a round cutting ridge and forms a curved central surface; and wherein generating lines of the curved central surface are parallel to a bottom surface of the cutter or have a sloped angle to the bottom surface of the cutter. 
     
     
         16 . The cutter of  claim 15 , wherein the curved central surface can be a concave or convex surface. 
     
     
         17 . The cutter of  claim 1 , wherein the inclined surface comprises two cutting ridges which do not intersect at a point on a cutting surface and extend from a cutting point to the trailing edge. 
     
     
         18 . The cutter of  claim 17 , wherein the two cutting ridges separate the inclined surface into two side flat surfaces and a central flat surface. 
     
     
         19 . The cutter of  claim 17 , wherein the two cutting ridges are round; wherein a central flat surface slants downward from the cutting edge to the trailing edge; and wherein two side flat surfaces slant downward from the two cutting ridges to a periphery of the inclined surface. 
     
     
         20 . The cutter of  claim 17 , wherein the two cutting ridges separate the inclined surface into concave or convex surfaces. 
     
     
         21 . The cutter of  claim 1 , wherein the ultra-hard layer is formed of polycrystalline diamond. 
     
     
         22 . The cutter of  claim 1 , wherein the inclined surface is loft cut by electrical discharge machining, by laser processing, by grinding, by other material reduction methods, or net shaping from a sintering process. 
     
     
         23 . A drill bit comprising at least one cutter of  claim 1 .