Cutting tool

A cutting tool comprising:

• an upper surface;
• a lower surface that is disposed to face the upper surface;
• a side surface that connects the upper surface and the lower surface;
• a cutting edge that includes a pair of major cutting edges and a corner cutting edge having a projected curve shape which connects the pair of major cutting edges, the cutting edge being formed at a part of an intersecting edge of the upper surface and the side surface;
• a first upper surface and a second upper surface formed on the upper surface, with the second upper surface being more distant from the lower surface than the first upper surface;
• an inclined surface that connects the first upper surface and the second upper surface;
• one groove disposed on the second upper surface to extend on a bisector of an angle formed by the pair of major cutting edges, or two or more grooves disposed on the second upper surface to extend linearly symmetric with respect to the bisector;
• and
• a first projection and a second projection which are formed to be projected from the inclined surface, wherein
• the first projection extends on an extended line of the groove, or along a line parallel with the extended line, wherein
• the second projection is disposed to be linearly symmetric with respect to the bisector of the angle formed by the pair of major cutting edges, and extends to be gradually closer to the extended line of the groove as gradually approaching the corner cutting edge,
• at an intersection between the corner cutting edge and the bisector of the angle formed by the pair of major cutting edges in a top view, L1<L2 is established, where L1 is a distance from a virtual line intersecting perpendicularly to the bisector of the angle formed by the major cutting edges to a leading end of the first projection, and L2 is a distance from the virtual line to a leading end of the second projection, and
• in a side view from a direction that is perpendicular to the bisector of the angle formed by the major cutting edges and that is parallel with the upper surface, h1<h2<h3 is established, where h1 is a distance from the first upper surface to a top of the first projection, h2 is a distance from the first upper surface to a top of the second projection, and h3 is a distance from the first upper surface to the second upper surface respectively, in a direction perpendicular to the upper surface.