A cutting insert includes: a polygonal shaped upper surface; a lower surface; a side surface connected to each of the upper and lower surfaces; and an upper cutting edge located at the intersection of the upper surface and the side surface. The upper surface alternately includes three major corners and three minor corners. The upper cutting edge includes: a corner cutting edge; a minor cutting edge inclined toward the lower surface as separating from the corner cutting edge at a first inclination angle; and a major cutting edge inclined toward the lower surface as separating from the minor cutting edge at a second inclination angle. The corner cutting edge, the minor cutting edge and the major cutting edge are located sequentially from a first major corner to each of first and second minor corners, both of which are adjacent to the first major corner.

A cutting insert comprises an upper surface including a first corner, and a second and third corner, respectively, adjacent to both sides of the first corner. The upper surface sequentially includes a rake surface along an upper cutting edge, inclined toward a lower surface, going inward from the upper cutting edge at a rake angle on a basis of a perpendicular plane perpendicular to a central axis extending between the upper and lower surfaces, and a connection surface more inward than the rake surface, inclined toward the lower surface, going inward at a connection angle on the basis of the perpendicular plane. An intersecting part of the rake surface and the connection surface includes a highest position in a portion of the intersecting part corresponding to a minor rake surface. A cutting tool with cutting insert, and a method of producing a machined product using the cutting tool are provided.

In a cutting insert according to an embodiment of the present invention, an upper surface sequentially includes a first rake surface and a second rake surface. The first rake surface being inclined toward the lower surface as going inward from the cutting edge at a first rake angle on a basis of a perpendicular plane perpendicular to a central axis extending between the upper surface and a lower surface. The second rake surface is located more inward than the first rake surface and is inclined toward the lower surface at a second rake angle different from the first rake angle on the basis of the perpendicular plane. An intersecting part of the first rake surface and the second rake surface includes a protruded part located at a highest position in a region of the intersecting part along the second side surface. A cutting tool with the cutting insert, and a method of producing a machined product by using the cutting tool are also provided.

A cutting insert has an upper surface, a lower surface, a side surface connecting the upper and lower surfaces. An intersecting edge between the upper surface and the side surface is provided with a cutting edge. The cutting edge has, in order, a second major cutting edge, a first major cutting edge, a corner cutting edge connected to these major cutting edges, and a flat cutting edge. An obtuse interior first angle () is formed by the second and first major cutting edges. A interior second angle () formed by the flat cutting edge and the first major cutting edge is larger than an interior third angle () formed by the flat cutting edge and the second major cutting edge. A land is provided adjacent to the first major cutting edge, a width of the land increasing toward the first corner cutting edge.

A double-sided milling insert for high feed milling of metal workpieces includes upper and lower faces facing in opposite directions and convex clearance surfaces extending between the upper and lower faces. Each one of the faces includes a recessed support surface. The support surfaces are substantially parallel to each other and have a cavity therein for receiving a fastening device. Intersections of the convex clearance surfaces with the upper and lower faces form convex cutting edges when seen in a plan view. A rake face is provided adjacent the convex cutting edges. Each convex cutting edge is concave when seen in a side view and includes a substantially straight cutting edge portion on each side of a curved cutting edge portion when seen in plan view. A milling tool with a plurality of such inserts and a method of high feed milling using this tool are also disclosed.

Ceramic end mill with cutting edge portion including gashes between cutting edges and adjacent in a rotation direction. Center cut edges are formed at end cutting edges close to and facing rotation axis O. Center grooves are formed on rear sides of center cut edges and end cutting edges in the rotation direction continuous with a radial direction. The center grooves are continuous with positions where end cutting edge second surfaces face or approach rotation axis O. End cutting edge second surfaces are laid between center cut edges and end cutting edges. Center grooves are formed between end cutting edge second surfaces and center cut edges positioned on a rear side of end cutting edge second surfaces in the rotation direction. The center grooves pass on rotation axis O. Center grooves double as rake faces of the respective center cut edges and are continuous with the gashes.

An indexable cutting insert for a milling tool includes an upper side defining an upper extension plane and a lower side defining a lower extension plane parallel to the upper extension plane. A side surface connects the upper side and the lower side, the side surface including a plurality of upper main clearance surfaces and secondary clearance surfaces. At least six identical and alternately usable upper cutting edges extend around the upper side. Each cutting edge has a chip removing main cutting edge portion and at least one secondary cutting edge portion. The main cutting edge portion is formed in a transition between the upper side and one of the upper main clearance surfaces. The secondary cutting edge portion is formed in a transition between the upper side and one of the secondary clearance surfaces between two main cutting edge portions. The upper main clearance surfaces are formed at an obtuse inner angle with respect to the upper extension plane as seen in side elevation view.

A double-sided milling insert for high feed milling of metal workpieces includes upper and lower faces facing in opposite directions and convex clearance surfaces extending between the upper and lower faces. Each one of the faces includes a recessed support surface. The support surfaces are substantially parallel to each other and have a cavity therein for receiving a fastening device. Intersections of the convex clearance surfaces with the upper and lower faces form convex cutting edges when seen in a plan view. A rake face is provided adjacent the convex cutting edges. Each convex cutting edge is concave when seen in a side view and includes a substantially straight cutting edge portion on each side of a curved cutting edge portion when seen in plan view. A milling tool with a plurality of such inserts and a method of high feed milling using this tool are also disclosed.

A cutting insert of an embodiment of the present invention includes an upper surface, a lower surface, a side surface connected to each of the upper surface and the lower surface, and an upper cutting edge located at an intersection of the upper surface and the side surface. The lower surface includes a mount part having alternately three first top portions spaced a distance a away from a central axis extending between the upper and lower surfaces and three second top portions spaced a distance b away from the central axis in a bottom view. The mount part further has a concave part including at least the central axis. The second top portions are located closer to the upper surface than the first top portions. A cutting tool with the cutting insert, and a method of manufacturing a machined product by using the cutting tool are also provided.

A cutting insert comprises a first surface sequentially including a first and second inclined surface. The first inclined surface is inclined toward the second surface, going inward from the edge at a first inclined angle on a basis of a perpendicular plane perpendicular to a central axis extending between the first surface and a second surface. The second inclined surface, located more inward than the first inclined surface, is inclined toward the second surface at a second inclined angle different from the first inclined angle on the basis of the perpendicular plane. An intersecting part of the first inclined surface and the second inclined surface includes a first part located at a highest position in a region of the intersecting part along the second side surface. A cutting tool with the cutting insert, and a method of producing a machined product using the cutting tool are provided.