Abstract: An insert may include a first surface, a second surface, a ridge line located at an intersection of the first surface and the second surface. The first surface may include a first corner, a first side and a second side. The ridge line may include a corner cutting edge located on the first corner, a first cutting edge located on the first side, and a second cutting edge located on the second side. The first surface may further include a first region located from the first cutting edge toward a midportion of the first surface, a second region located from the second cutting edge toward the midportion of the first surface, and a concave part located on at least one of the first region and the second region.

Abstract: A cutting insert may include a first surface, a second surface, a first lateral surface, a second lateral surface, a first cutting edge and a second cutting edge. The first lateral surface may include a first inclined surface located along the first cutting edge, a second inclined surface located along the first inclined surface, a third inclined surface located along the second cutting edge, a fourth inclined surface located along the third inclined surface, and a flat surface located along the second inclined surface and the fourth inclined surface. A second inclination angle of the second inclined surface may be smaller than a first inclination angle of the first inclined surface. A fourth inclination angle of the fourth inclined surface may be larger than a third inclination angle of the third inclined surface.

Abstract: An insert may include a first surface, a second surface, a ridge line located at an intersection of the first surface and the second surface. The first surface may include a first corner, a first side and a second side. The ridge line may include a corner cutting edge located on the first corner, a first cutting edge located on the first side, and a second cutting edge located on the second side. The first surface may further include a first region located from the first cutting edge toward a midportion of the first surface, a second region located from the second cutting edge toward the midportion of the first surface, and a concave part located on at least one of the first region and the second region.

Abstract: An insert may include a first surface, a second surface, a ridge line located at an intersection of the first surface and the second surface. The first surface may include a first corner, a first side and a second side. The ridge line may include a corner cutting edge located on the first corner, a first cutting edge located on the first side, and a second cutting edge located on the second side. The first surface may further include a first region located from the first cutting edge toward a midportion of the first surface, a second region located from the second cutting edge toward the midportion of the first surface, and a concave part located on at least one of the first region and the second region.

Abstract: A cutting insert may include a base including a first surface, a second surface and a lateral surface. The first surface may include a first corner, a second corner and a first side. The first side may include a first portion, a second portion, a third portion and a fourth portion in this order in a direction from the first corner to the second corner. An imaginary straight line being in contact with the first portion may be a reference line in a front view of the first surface. Inclination angles of the first portion, the second portion, the third portion and the fourth portion relative to the reference line may be respectively a first angle, a second angle, a third angle and a fourth angle. The third angle may be smaller than each of the second angle and the fourth angle.

Abstract: A cutting insert may include a first surface having a polygonal shape, a second surface, and a cutting edge located on a ridge line where the first surface intersects with the second surface. The first surface may include a first corner, a second corner, a third corner, a first side, and a second side. In a plan view of the first surface, the first side may have a straight line shape or a convex shape protruded outward relative to a first imaginary line connecting the first corner and the second corner, and the second side may have a concave shape recessed inward relative to a second imaginary line connecting the first corner and the third corner.

Abstract: A cutting insert may include a first surface having a polygonal shape, a second surface, a third surface and a cutting edge. The first surface may include a first corner, a first side, a first inclined surface located along the first side, and a second inclined surface located along the second side. In a plan view of the first surface, a width of the first inclined surface in a direction orthogonal to the first side may become larger as approaching the second side. A width of the second inclined surface in a direction orthogonal to the second side may become larger as approaching the first side.

Abstract: A cutting insert may include a first surface, a second surface, a first lateral surface, a second lateral surface, a first cutting edge and a second cutting edge. The first lateral surface may include a first inclined surface located along the first cutting edge, a second inclined surface located along the first inclined surface, a third inclined surface located along the second cutting edge, a fourth inclined surface located along the third inclined surface, and a flat surface located along the second inclined surface and the fourth inclined surface. A second inclination angle of the second inclined surface may be smaller than a first inclination angle of the first inclined surface. A fourth inclination angle of the fourth inclined surface may be larger than a third inclination angle of the third inclined surface.

Abstract: An insert may include a first surface, a second surface, a ridge line located at an intersection of the first surface and the second surface. The first surface may include a first corner, a first side and a second side. The ridge line may include a corner cutting edge located on the first corner, a first cutting edge located on the first side, and a second cutting edge located on the second side. The first surface may further include a first region located from the first cutting edge toward a midportion of the first surface, a second region located from the second cutting edge toward the midportion of the first surface, and a concave part located on at least one of the first region and the second region.

Abstract: A cutting insert may include a first surface having a polygonal shape, a second surface, and a cutting edge located on a ridge line where the first surface intersects with the second surface. The first surface may include a first corner, a second corner, a third corner, a first side, and a second side. In a plan view of the first surface, the first side may have a straight line shape or a convex shape protruded outward relative to a first imaginary line connecting the first corner and the second corner, and the second side may have a concave shape recessed inward relative to a second imaginary line connecting the first corner and the third corner.

Abstract: A cutting insert may include a first surface having a polygonal shape, a second surface, a third surface and a cutting edge. The first surface may include a first corner, a first side, a first inclined surface located along the first side, and a second inclined surface located along the second side. In a plan view of the first surface, a width of the first inclined surface in a direction orthogonal to the first side may become larger as approaching the second side. A width of the second inclined surface in a direction orthogonal to the second side may become larger as approaching the first side.

Abstract: A cutting insert of an embodiment includes an upper surface including a first upper cutting edge and a second upper cutting edge, a lower surface including a first lower cutting edge and a second lower cutting edge, and a side surface. The side surface includes a first surface extending from the second upper cutting edge, a second surface extending from the first lower cutting edge, a third surface extending from the first upper cutting edge, and a fourth surface extending from the second lower cutting edge. The first surface and the fourth surface are parallel to a central axis. The second surface is inclined so as to depart from the central axis as going from the lower surface toward the upper surface. The third surface is inclined so as to depart from the central axis as going from the upper surface toward the lower surface.

Abstract: A cutting insert of an embodiment includes an upper surface including a first upper cutting edge and a second upper cutting edge, a lower surface including a first lower cutting edge and a second lower cutting edge, and a side surface. The side surface includes a first surface extending from the second upper cutting edge, a second surface extending from the first lower cutting edge, a third surface extending from the first upper cutting edge, and a fourth surface extending from the second lower cutting edge. The first surface and the fourth surface are parallel to a central axis. The second surface is inclined so as to depart from the central axis as going from the lower surface toward the upper surface. The third surface is inclined so as to depart from the central axis as going from the upper surface toward the lower surface.

Abstract: A cutting insert has: first sub cutting edges at positions corresponding to first corner portions of a polygonal top surface; second sub cutting edges at positions corresponding to second corner portions; and main cutting edges on side portions. In a side view, each of the main cutting edges has a first cutting edge adjacent to the first sub cutting edge, a second cutting edge adjacent to the second sub cutting edge, and a third cutting edge between the first cutting edge and the second cutting edge. Each of the main cutting edges inclines such that the height thereof decreases from a portion adjacent to the first sub cutting edge to a portion adjacent to the second sub cutting edge. An inclination angle of the third cutting edge is greater than inclination angles of the first cutting edge and the second cutting edge.

Abstract: A cutting insert of an embodiment includes an upper surface including a first upper cutting edge and a second upper cutting edge, a lower surface including a first lower cutting edge and a second lower cutting edge, and a side surface. The side surface includes a first surface extending from the second upper cutting edge, a second surface extending from the first lower cutting edge, a third surface extending from the first upper cutting edge, and a fourth surface extending from the second lower cutting edge. The first surface and the fourth surface are parallel to a central axis. The second surface is inclined so as to depart from the central axis as going from the lower surface toward the upper surface. The third surface is inclined so as to depart from the central axis as going from the upper surface toward the lower surface.

Abstract: A cutting insert of an embodiment includes an upper surface including a first upper cutting edge and a second upper cutting edge, a lower surface including a first lower cutting edge and a second lower cutting edge, and a side surface. The side surface includes a first surface extending from the second upper cutting edge, a second surface extending from the first lower cutting edge, a third surface extending from the first upper cutting edge, and a fourth surface extending from the second lower cutting edge. The first surface and the fourth surface are parallel to a central axis. The second surface is inclined so as to depart from the central axis as going from the lower surface toward the upper surface. The third surface is inclined so as to depart from the central axis as going from the upper surface toward the lower surface.

Abstract: A cutting insert of an embodiment includes an upper surface including a first upper cutting edge and a second upper cutting edge, a lower surface including a first lower cutting edge and a second lower cutting edge, and a side surface. The side surface includes a first surface extending from the second upper cutting edge, a second surface extending from the first lower cutting edge, a third surface extending from the first upper cutting edge, and a fourth surface extending from the second lower cutting edge. The first surface and the fourth surface are parallel to a central axis. The second surface is inclined so as to depart from the central axis as going from the lower surface toward the upper surface. The third surface is inclined so as to depart from the central axis as going from the upper surface toward the lower surface.

Abstract: A cutting insert has: first sub cutting edges at positions corresponding to first corner portions of a polygonal top surface; second sub cutting edges at positions corresponding to second corner portions; and main cutting edges on side portions. In a side view, each of the main cutting edges has a first cutting edge adjacent to the first sub cutting edge, a second cutting edge adjacent to the second sub cutting edge, and a third cutting edge between the first cutting edge and the second cutting edge. Each of the main cutting edges inclines such that the height thereof decreases from a portion adjacent to the first sub cutting edge to a portion adjacent to the second sub cutting edge. An inclination angle of the third cutting edge is greater than inclination angles of the first cutting edge and the second cutting edge.