CUTTING INSERT, CUTTING TOOL, AND METHOD FOR MANUFACTURING CUT WORKPIECE USING SAME

摘要

A cutting insert, a cutting tool and method of manufacturing a machined product. The cutting insert includes: upper and lower surfaces; a side surface; a cutting edge; and a rake portion on the upper surface. The cutting edge includes major and minor cutting edges that are convex toward outside of the main body portion. The minor cutting edge has a curvature radius smaller than a curvature radius of the major cutting edge. The rake portion is inclined and approaches the lower surface as moving from the major cutting edge toward inside of the main body portion and is located along the major cutting edge. An inclination angle of the rake portion becomes smaller as moving from a part continuous with one end of the major cutting edge toward a part continuous with center of the major cutting edge.

主权项

1. A cutting insert comprising:
a main body portion comprising:
an upper surface;a lower surface;a side surface connected to the upper surface and the lower surface; anda cutting edge located at an intersection of the upper surface and the side surface;a first rake portion on the upper surface; wherein the cutting edge comprises:
an arcuate major cutting edge that is convex toward outside of the main body portion; andan arcuate minor cutting edge that is convex toward outside of the main body portion and that has a curvature radius smaller than a curvature radius of the arcuate major cutting edge, wherein the first rake portion is inclined to extend toward the lower surface as viewed in a direction from the arcuate major cutting edge toward an inside of the main body portion and is located along the arcuate major cutting edge, and wherein an inclination angle of the first rake portion decreases as viewed in a direction from a part continuous with one end of the arcuate major cutting edge toward a part continuous with center of the arcuate major cutting edge.