Cutter having working surface with an edge chamfer of varying geometry

摘要

A cutter comprises a working surface 102, 142 with an edge 106, 146 and a chamfer 104, 144 along the edge 106, 146, the chamfer 104, 144 having a varied geometry, the working surface 102, 142 may be planar or shaped and may have at least one depression 150a, 150b, 150c extending from a portion of the working surface 142 interior to the edge 146 and intersecting with the chamfer 144 at a critical region along the edge 146. The varied geometry may comprise a varied width of chamfer or angle of chamfer or both varied width and varied angle. The invention also covers a drill bit comprising a bit body and at least one aforementioned cutter and a drill bit comprising a bit body, a blade formed on the bit body and a plurality of aforementioned cutters. Also disclosed is a cutter comprising a support body having an axial orientation, a working surface secured to the support body, the working surface having a plurality of depression oriented at oblique/obtuse angles relative to the axial orientation of the support body and a chamfered edge with varied width chamfer between the plurality of depressions. Also disclosed is a cutter comprising a support body and defining a non-planar interface and a polycrystalline diamond material bonded to the interface and defining a working surface, wherein the working surface has at least one depression and the interface comprises a portion of the support surface generally aligned with the at least one depression.