Patent ID: 8905683

Claim:
A cutting tool ( 20 , 120 ) comprising a tool body ( 22 ) with at least one seating surface ( 24 ), at least one cutting insert ( 26 , 126 ), and at least one fastening member ( 28 ) for removably securing the at least one cutting insert ( 26 , 126 ) to the at least one seating surface ( 24 ), the at least one cutting insert ( 26 , 126 ) having opposing top and bottom surfaces ( 32 , 34 ) with a peripheral side surface ( 36 ) and a central axis (A 1 ) extending therebetween, and a clamping bore ( 38 ) in the top surface ( 32 ), the peripheral side surface ( 36 ) including at least one flank surface ( 40 ), where at least one cutting edge ( 42 ) is formed at the intersection of the at least one flank surface ( 40 ) with at least the top surface ( 32 ), and the clamping bore ( 38 ) including at least two upper clamping portions (UC 1 , UC 2 ) intersecting a first horizontal plane (PH 1 ) and at least two lower clamping portions (LC 1 , LC 2 ) intersecting a second horizontal plane (PH 2 ), each of the clamping portions (UC 1 , UC 2 , LC 1 , LC 2 ) representing a distinct region of the clamping bore ( 38 ), and the first and second horizontal planes (PH 1 , PH 2 ) being perpendicular to the central axis (A 1 ) and spaced apart from each other, wherein upper imaginary lines (LU 1 , LU 2 ) tangential to the at least two upper clamping portions (UC 1 , UC 2 ) and coplanar with the central axis (A 1 ), form zero or acute first clamping angles (α 1 ) with the central axis (A 1 ), and lower imaginary lines (LL 1 , LL 2 ) tangential to the at least two lower clamping portions (LC 1 , LC 2 ) and coplanar with the central axis (A 1 ), form zero or acute second clamping angles (α 2 ) with the central axis (A 1 ), wherein the first and second clamping angles (α 1 , α 2 ) are different, and wherein exactly two upper clamping portions (UC 1 , UC 2 ) and exactly two lower clamping portions (LC 1 , LC 2 ), representing four operative clamping portions (UC 1 , UC 2 , LC 1 , LC 2 ), are in simultaneous clamping contact with an equal number of corresponding clamping zones (UZ 1 , UZ 2 , LZ 1 , LZ 2 ) on the fastening member ( 28 ).