Cutting tool with replaceable abutment members and toolholder and cutting insert therefor

A cutting tool comprising:

• a toolholder including a bottom abutment surface, a projection extending upwardly from the bottom abutment surface, the projection including an internally threaded opening, the internally threaded opening having a central axis that is offset from a central axis of the projection in a first direction, a clamping screw having external threads for mating with internal threads of the internally threaded opening and a head having a bottom clamping surface shaped as a truncated cone for contacting an insert clamping surface and urging an insert in substantially the first direction when the clamping screw is tightened relative to the toolholder and the insert, and at least one abutment member extending from a side wall of the projection in a radial direction, each abutment member having an abutment point, at least the abutment point of the at least one abutment member being closer to the central axis of the projection than to the central axis of the internally threaded opening;
• and
• a cutting insert attachable to the toolholder, the insert including a bottom supporting surface for supporting the insert against the bottom abutment surface, a top surface, and a through hole for receiving the projection extending from the bottom supporting surface to the top surface, the through hole including an internal, cylindrical wall portion and an inverted truncated conical insert clamping surface between the cylindrical and the top surface, wherein the through hole includes a plurality of recesses having recess supporting surfaces in the cylindrical wall arranged to receive the at least one abutment member so that the abutment point of each abutment member of the at least one abutment member abuts against a corresponding one of the recess supporting surfaces when the clamping screw is tightened relative to the toolholder and the insert and moves the insert in the first direction.

A cutting insert comprising:

• a bottom surface;
• a top surface spaced from and parallel with the bottom surface;
• and
• a through hole extending from the bottom surface to the top surface, the through hole including an internal, circular cylindrical wall portion, an inverted truncated conical insert clamping surface between the circular cylindrical wall portion and the top surface, and a plurality of recesses having recess supporting surfaces located in the circular cylindrical wall portion, wherein each of the plurality of recesses extend to and terminate in the clamping surface.