| 摘要 |
PCT No. PCT/EP94/01626 Sec. 371 Date Mar. 16, 1995 Sec. 102(e) Date Mar. 16, 1995 PCT Filed May 19, 1994 PCT Pub. No. WO94/27772 PCT Pub. Date Dec. 8, 1994A drilling tool having an elongated body with a longitudinal axis and provided with at least one insert receiving pocket and an indexable cutting insert for use with the drilling tool for performing drilling action is disclosed. The insert of the drilling tool includes a rake face, relief flank faces, a base, a plurality of cutting edges, each defined between the rake face and adjacent relief flank face and included between two adjacent cutting corners. Each cutting edge has at least one set of component cutting edges, each set having two pairs of component cutting edges merging in a common point, each pair comprising a first and a second component cutting edge merging via a bridging section directed towards a central line constituting or parallel to a median line of the insert and passing through the common point. The component cutting edges are oriented with respect to the central line so that an outermost extremity of the second component cutting edge is closer to a center of the insert and to the central line than the outermost extremity of the first component cutting edge. This ensures that during the drilling action, a line parallel to the longitudinal axis and passing through the outermost extremity of the first component cutting edge intersects the second component cutting edge and the extremities overlap. |
