Patent ID: 8647027

Claim:
A cutting insert ( 24 ) comprising: opposing top and bottom surfaces ( 36 , 38 ) and a peripheral surface ( 40 ) extending therebetween, the peripheral surface ( 40 ) comprising a front arcuate surface ( 42 ) and a rear surface ( 44 ), the front arcuate surface ( 42 ) meeting the top and bottom surfaces ( 36 , 38 ) at two edges ( 58 , 60 ), at least one of the edges ( 58 ) comprising a cutting edge; the rear surface ( 44 ) comprising a central back surface ( 46 ), two side abutment surfaces ( 48 , 50 ) and two rear abutment surfaces ( 52 , 54 ), the central back surface ( 46 ) being located between the two side abutment surfaces ( 48 , 50 ) which extend forwardly therefrom, each side abutment surface ( 48 , 50 ) being adjacent to a respective rear abutment surface ( 52 , 54 ), the central back surface ( 46 ) and the two side abutment surfaces ( 48 , 50 ) being located on a protuberance ( 56 ) of the cutting insert ( 24 ), the protuberance ( 56 ) protruding beyond the rear abutment surfaces ( 52 , 54 ) in a direction away from a central region of the front arcuate surface ( 42 ); and an insert through hole ( 30 ) passing between the top and bottom surfaces ( 36 , 38 ).