Cutting insert, cutting tool, and method for manufacturing cut workpiece using same

A cutting insert comprising:

• a main body portion comprising:
• a first surface;
• a second surface;
• a side surface connected to the first surface and the second surface;
• an edge located at an intersection of the first surface and the side surface;
• and
• a first inclined portion on the first surface;
• wherein the edge comprises:
• a first edge that is arcuate and convex toward outside of the main body portion;
• and
• a second edge that is arcuate and convex toward outside of the main body portion and that has a curvature radius smaller than a curvature radius of the first edge,
• wherein the first inclined portion is inclined to extend toward the second surface as viewed in a direction from the first edge toward an inside of the main body portion and is located along the first edge,
• wherein an inclination angle of the first inclined portion decreases along a path from a part continuous with one end of the first edge toward a part continuous with center of the first edge,
• wherein the first edge is inclined to extend toward the second surface with increasing distance from the second edge,
• wherein the second edge is inclined to extend toward the second surface with increasing distance from the first edge, and
• wherein the first edge is curved toward a side away from the second surface in side view.

A cutting insert comprising:

• a main body portion comprising:
• a first surface;
• a second surface;
• a side surface connected to the first surface and the second surface;
• an edge located at an intersection of the first surface and the side surface;
• and
• a first inclined portion on the first surface;
• wherein the edge comprises:
• a first edge that is arcuate and convex toward outside of the main body portion;
• and
• a second edge that is arcuate and convex toward outside of the main body portion and that has a curvature radius smaller than a curvature radius of the first edge,
• wherein the first inclined portion is inclined to extend toward the second surface as viewed in a direction from the first edge toward an inside of the main body portion and is located along the first edge,
• wherein an inclination angle of the first inclined portion decreases along a path from a part continuous with one end of the first edge toward a part continuous with center of the first edge,
• wherein the side surface comprises:
• a first area connected to the first edge;
• and
• a second area connected to the second edge and inclined to extend toward a central axis passing through a center of the first surface and a center of the second surface with increasing distance from the second edge, and
• wherein a first angle which is an angle of the first area with respect to the central axis is smaller than a second angle which is an angle of the second area with respect to the central axis.