A cutting tool including an insert and a holder to which the insert is secured. The insert has a rod with a substantially circular transverse cross-section. The insert includes a shank portion and a cutting edge portion. The cutting edge portion is located at an end portion continuous with the shank portion. In the cutting edge portion, one end of a cutting edge ridge protrudes toward the periphery of the rod. When the insert is secured to the holder, the cutting edge ridge has a negative radial rake angle.

In a cutting insert of an embodiment of the present invention, an upper surface includes a first corner, and a second corner and a third corner respectively adjacent to both sides of the first corner. The upper surface sequentially includes a rake surface located along an upper cutting edge and inclined toward a lower surface as 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 located more inward than the rake surface and inclined toward the lower surface as 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 the minor rake surface. A cutting tool with the cutting insert, and a method of producing a machined product by using the cutting tool are also provided.

In a cutting insert according to an embodiment of the present invention, an upper cutting edge includes, sequentially from a first corner to a second corner, a corner cutting edge, a minor cutting edge inclined as separating from the corner cutting edge at a first inclination angle on a basis of a vertical plane perpendicular to a central axis extending between upper and lower surfaces, and a major cutting edge inclined as separating from the minor cutting edge at a second inclination angle on the basis of the vertical plane so as to become more closer to the lower surface than the minor cutting edge. A cross section of a rake surface obtained by cutting an inwardly located end portion thereof along a direction of the central axis has a straight line shape or concave shape in a region crossing over at least a minor rake surface and a major rake surface. 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 that has, in an upper surface, a convex portion including a main portion having a flat upper end surface, a first portion projecting from the main portion to a corner portion of the upper surface, a second portion projecting from the first portion to the corner portion, and a third portion projecting from the second portion to the corner portion. Upper end heights of the second portion and the third portion are fixed toward the corner portion, respectively. The first portion and the second portion are connected by a first flat inclined wall surface, the second portion and the third portion are connected by a second wall surface of a convex curved surface, and a front end of the third portion and the breaker groove are connected by a third wall surface of a convex curved surface.

A method for designing a cutting edge of a cutting element configured for removing material from a workpiece to leave therein a desired end profile (B22,B24,B26). The method comprises the steps of modeling a desired end profile (B22,B24,B26) of the workpiece, the profile having a longitudinal axis and being defined by a bottom surface (B12), a side surface (B16) and an adjustment surface (B14) extending therebetween; defining a lead profile plane (RP.sub.L) and an trail profile plane (RP.sub.T) spaced therefrom, each of the planes being oriented perpendicular to the longitudinal axis; determining a profile contour defined by the intersection line between the end profile (B22,B24,B26) and the lead profile plane (RP.sub.L). The contour profile includes a bottom contour, an adjoining contour and a side contour defined as the intersection lines between the lead profile plane (RP.sub.L) and the bottom surface (B12), the adjustment surface (B14) and the side surface (B16) respectively; designing a rake surface and a relief surface, the intersection line between which defines a cutting edge lying in the adjoining surface (B14) and spanning between the lead profile plane (RP.sub.L) and the trail profile plane (RP.sub.T). The cutting edge is designed such that in any reference plane (RP; FIG. 6A) oriented perpendicularly to the cutting edge, the intersection between each of the rake surface and the relief surface with the reference plane (RP) defines a respective rake line (RK; FIG. 7) and relief line (RF; FIG. 7), the angle (.sub.B) between the lines RK,RF) being equal to or smaller than a similar angle (.sub.B) taken along each of a plurality of similar reference planes (RP) disposed between the reference plane (RP.sub.n) and the lead profile plane (RP.sub.L).

In a cutting insert of an embodiment of the present invention, an upper surface includes a first corner, and a second corner and a third corner respectively adjacent to both sides of the first corner. The upper surface sequentially includes a rake surface located along an upper cutting edge and inclined toward a lower surface as 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 located more inward than the rake surface and inclined toward the lower surface as 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 the minor rake 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 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 tool having an indexable cutting insert with three cutting portions, the cutting insert is removably securable to an insert holder by means of a fastener. The cutting insert has two opposing end surfaces with a peripheral side surface extending therebetween. At least one end surface has a central boss protruding therefrom with a raised support surface, and the peripheral side surface has three abutment recesses. In an end view of the cutting insert, each of the three abutment recesses is visible and located inside a first imaginary circle circumscribing the visible central boss. A holding portion of the insert holder has a seating surface with at least one protuberance protruding therefrom. The support surface is in clamping contact with the seating surface, and exactly two of the three abutment recesses are engaged with the at least one protuberance.

A cutting tool including an annular cutter body having at least one V-shaped pocket formed therein and a cutting tool cartridge configured to be received in the at least one pocket of the cutter body. The cutting tool cartridge including a main body. The main body includes a cutting head having a cutting chip control portion and a pocket configured to receive a cutting insert.