DRILL BIT WITH WEDGE CLAMP FOR CUTTERS Russian patent published in 2016 - IPC E21B10/48 

FIELD: mining.

SUBSTANCE: claimed drill bit comprises the body with coupling thread, sectors made at crown ring of the bit body separated by flushing channels. Besides, it includes the well- and core-forming inserts and clamping wedges fitted at the negative leading angle to the well bottom and at negative leading angle in plan to the cutting lateral inner and outer surfaces. Said crown ring is provided with blind rectangular slits to receive the tetragonal well- and core-forming inserts made of shock-and-heat resistant material, for example, nanopowders of cubic boron nitride. Clamping wedges are fitted in wedge-shape slots between the inserts and flushing channels so that said inserts are clamped via mid wall to the flushing slit rear wall. Note here that said wedges face the drill bit end and are locked at the bed by spacer wedges with chamfers made at self-braking angles.

EFFECT: higher reliability of fastening, higher clamping force, longer life, better bottomhole cleaning.

4 cl, 2 dwg