INDEXABLE DRILL INSERT AND ROTARY CUTTING TOOL EMPLOYING SAME

摘要

An insert includes four identical cutting edges disposed at the intersection of top and side surfaces surface. Each cutting edge includes a first part edge disposed tangent to a first reference circle aligned about the central mounting aperture; a second part edge extending from the first part edge, the second part edge being connected to the first part edge via a convex curved portion; a third part edge disposed tangent to a second reference circle aligned about the central mounting aperture, the second reference circle having a smaller diameter than the first reference circle, the third part edge being connected to the second part edge via a concave curved portion; and a convexly curved corner portion extending from the third part edge of one of the identical cutting edges to the first part edge of another one of the identical cutting edges.

主权项

1. An indexable insert comprising:
a top surface; a bottom surface; a side surface extending between the top and bottom surfaces from multiple sides of the insert; a central mounting aperture extending between the top surface and the bottom surface; and a plurality of identical cutting edges disposed at the intersection of the top surface and the side surface, each cutting edge comprising:
a first part edge disposed tangent to a first reference circle aligned about the central mounting aperture;a second part edge extending from the first part edge, the second part edge being connected to the first part edge via a convex curved portion;a third part edge disposed tangent to a second reference circle aligned about the central mounting aperture, the second reference circle-EC having a smaller diameter than the first reference circle being connected to the second part edge via a concave curved portion; anda convexly curved corner portion extending from the third part edge of one of the identical cutting edges to the first part edge of another one of the identical cutting edges.