Drill cutting insert

摘要

A drill cutting insert has a cutting edge at a transition between a side surface and a top side which is formed with n identical cutting corners and n identical partial cutting edges —with nε{3, 4} —extending between the cutting corners. Each of the n partial cutting edges has: adjoining a first cutting corner, a main lip which is straight in plan view of the top side; adjoining the other cutting corner, a secondary lip which is straight in plain view of the top side, and a transition section, via which the main lip and the secondary lip merge into one another and which has a convex section adjoining the main lip and a concave section adjoining the secondary lip. The main and secondary lips enclose on the outside an angle a α<180° in plan view of the top side.

主权项

1. A drill cutting insert, comprising:
a top surface, a bottom surface, and a circumferential side face connecting said top surface with said bottom surface; a cutting edge formed at a transition between said side face and said top surface, said cutting edge having n identical cutting corners and n identical partial cutting edges, each extending between two respective said cutting corners, where nε{3, 4}; each of said n partial cutting edges having:
a main cutting edge adjoining a first cutting corner, said main cutting edge being straight in a top plan view onto said top surface;a secondary cutting edge adjoining another cutting corner, said secondary cutting edge being straight in a top plan view onto said top surface;said top surface being formed with a chip-conducting structure, having an increasing width along a partial cutting edge from said secondary cutting edge to said main cutting edge;a transition portion, by way of which said main cutting edge and said secondary cutting edge merge into one another, said transition portion having a convex portion adjoining said main cutting edge and a concave portion adjoining said secondary cutting edge; andsaid main cutting edge and said secondary cutting edge enclosing an angle α<180° with one another on an outside in a top view onto said top surface.