A cutting tool having a cutting edge member which forms at least one corner part, wherein a material for the cutting edge member is selected from either diamond, an ultrahigh-pressure sintered body containing cubic boron nitride or a PVD or CVD coating applied to a surface of the ultrahigh-pressure sintered body. At least part of an intersecting edge between an end surface of the cutting edge member and a peripheral side surface thereof is provided with a cutting edge. A chip breaker comprising a breaker wall surface is formed in the end surface of the cutting edge member. The breaker wall surface has at least one projected surface part which bulges outwardly from the cutting tool. As viewed from the end surface, the recessed surface part is arranged so as to be apart from a virtual plane A which is defined so as to divide the corner part into halves.

A cutting tool having a cutting edge member which forms at least one corner part, wherein a material for the cutting edge member is selected from either diamond, an ultrahigh-pressure sintered body containing cubic boron nitride or a PVD or CVD coating applied to a surface of the ultrahigh-pressure sintered body. At least part of an intersecting edge between an end surface of the cutting edge member and a peripheral side surface thereof is provided with a cutting edge. A chip breaker comprising a breaker wall surface is formed in the end surface of the cutting edge member. The breaker wall surface has at least one projected surface part which bulges outwardly from the cutting tool. As viewed from the end surface, the recessed surface part is arranged so as to be apart from a virtual plane A which is defined so as to divide the corner part into halves.

A cutting insert may include a base and a cutting part. The cutting part may include an upper surface, a first cutting edge and a second cutting edge. The first cutting edge may be located on a first ridgeline. The second cutting edge may be located on a second ridgeline. The upper surface may include a first inclined surface, protrusions and a first upheaved part. The first inclined surface may be located along the first ridgeline. The protrusions may be located side by side in a direction along the first ridgeline on the first inclined surface. The first upheaved part may be located at a side further away from the first ridgeline than the pair of protrusions. The second cutting edge may be inclined downward. An upper end of the first upheaved part may be located above the second cutting edge.

A cutting insert may include a base and a cutting part. The cutting part may include an upper surface, a first cutting edge and a second cutting edge. The first cutting edge may be located on a first ridgeline. The second cutting edge may be located on a second ridgeline. The upper surface may include a first inclined surface, protrusions and a first upheaved part. The first inclined surface may be located along the first ridgeline. The protrusions may be located side by side in a direction along the first ridgeline on the first inclined surface. The first upheaved part may be located at a side further away from the first ridgeline than the pair of protrusions. The second cutting edge may be inclined downward. An upper end of the first upheaved part may be located above the second cutting edge.

A cutting insert includes an upper surface and a cutting edge. The upper surface includes a first surface and a second surface which is located further inward than the first surface. The cutting edge includes a first cutting edge and a second cutting edge. The first surface includes a first region along the first cutting edge, a second region adjacent to the first region, and a third region which is adjacent to the second region and along the second cutting edge. The second surface includes a fourth region, a fifth region and a sixth region. A width of the second region is smaller than each of a width of the first region and a width of the third region. An inclination angle of the fifth region is smaller than each of an inclination angle of the fourth region and an inclination angle of the sixth region.

A cutting insert in a non-limiting aspect of the present disclosure may include an upper surface, a lower surface, a lateral surface and a cutting edge. The upper surface may include a first corner and a first side. The upper surface may further include a rake surface, a bottom surface and a raised surface. The bottom surface may include a first bottom surface and a second bottom surface. The first bottom surface may be located on a bisector of the first corner. The second bottom surface may be located inwardly of the first side. The first bottom surface may be an inclined surface located closer to the lower surface as going away from the first corner. The second bottom surface may be an inclined surface located further away from the lower surface as going away from the first side.

There is provided a cutting tool in which chip control is improved. A cutting edge member includes a first wall surface which includes a concave surface which is formed to be depressed in a direction away from an intersection point of an imaginary plane and a corner portion and toward the center of a cutting insert in an end view when viewed from a direction facing an end surface, a second wall surface which includes a convex surface which is provided to be connected to the first wall surface at a position spaced apart from the imaginary plane and is protruded in a direction away from the center of the cutting insert in the end view, a third wall surface which includes a convex surface which is provided to be connected to the first wall surface at a position spaced apart from the imaginary plane on an opposite side to the second wall surface across the imaginary plane and is protruded in a direction away from the center of the cutting insert in the end view, and a fourth wall surface which is provided in an area between the first wall surface and the intersection point in the end view, includes a convex surface which is protruded in a direction away from the center of the cutting insert in the end view, and has a height smaller than heights of the second wall surface and the third wall surface in a side view when viewed from a direction facing a side surface.

A cutting insert may include a first surface, a second surface and a third surface. The first surface may include a corner having a convex curvilinear shape and an inclined surface. The inclined surface may include a first inclined surface, a second inclined surface and a third inclined surface. The first inclined surface may be inclined at a first angle. The second inclined surface may be inclined at a second angle. The third inclined surface may be inclined at a third angle. The first inclined surface may have a concave curvilinear shape in a cross section orthogonal to a bisector of the corner. The second inclined surface may be a flat surface. The second angle may be smaller than either of the first angle and the third angle in a cross section which includes the bisector and is orthogonal to the reference plane.

The present invention provides a novel groove cutter with chip breaker, comprising: a cutter body; a cutter head arranged at the end part of the cutter body, a cutting edge being arranged at a bordering position of the cutter head; and a chip breaker arranged on the cutter head, wherein the chip breaker comprises a breaker bottom and a breaker wall, the breaker bottom being connected to the cutting edge, the breaker wall being arranged on one side of the breaker bottom away from the cutting edge, the breaker bottom being non-coplanar with the breaker wall, an intersecting line of the breaker bottom and the breaker wall comprising multiple connecting sections, and one curved transition section being arranged between two adjacent connecting sections. By means of the technical solutions provided in the present application, the problem that breaking chips in a groove machining process is difficult in the prior art can be solved.

The present invention provides a novel groove cutter with chip breaker, comprising: a cutter body; a cutter head arranged at the end part of the cutter body, a cutting edge being arranged at a bordering position of the cutter head; and a chip breaker arranged on the cutter head, wherein the chip breaker comprises a breaker bottom and a breaker wall, the breaker bottom being connected to the cutting edge, the breaker wall being arranged on one side of the breaker bottom away from the cutting edge, the breaker bottom being non-coplanar with the breaker wall, an intersecting line of the breaker bottom and the breaker wall comprising multiple connecting sections, and one curved transition section being arranged between two adjacent connecting sections. By means of the technical solutions provided in the present application, the problem that breaking chips in a groove machining process is difficult in the prior art can be solved.