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 shaft portion and a blade portion provided on a side surface of the shaft portion are included, and the blade portion includes cutting blades arranged in a plurality of lines on a side surface of the shaft portion along a peripheral direction, and arranged in a plurality of stages in an extending direction of a shaft center of the shaft portion in each line. Further, the cutting blade has a radial-direction clearance angle, a tip end-side clearance angle, and a base end-side clearance angle.

A double-sided cutting insert for milling has a first cutting edge formed at a transition from a top side to a circumferential lateral surface and a second cutting edge formed at a transition from a bottom side to the circumferential lateral surface. A reference plane (R) runs normal to an axis of symmetry (S). The cutting edges have main cutting edge portions and face cutting edge portions arranged in alternation, which extend between raised cutting corners and lowered cutting corners. The circumferential lateral surface has face free surfaces, which extend along the face cutting edge portion and which approach the axis of symmetry (S) with increasing distance from the associated face cutting edge portion. The circumferential lateral surface has main free surfaces, which extend along the main cutting edge portion and which move farther away from the axis of symmetry with increasing distance from the associated main cutting edge portion.

A milling tool comprising a cylindrical shaft part, which has a central axis and which is followed by a cylindrical cutting part comprising at least three circumferential cutting edges, which run helically and which are separated from one another by chip grooves. The circumferential cutting edges continue via cutting edge corner regions in end cutting edges, which run essentially radially and which subsequently slope away from the milling cutter face towards the central axis from radially outer end cutting edge sections, in each case with a cutting edge section, which is formed by ground-in end pockets. The cutting edge section slopes continuously all the way to the central axis. In the region of the milling cutter core, it is formed by a point thinning, which is introduced into the end pocket and by means of which a center cutting edge is created. Also, a method for producing the milling tool.

Disclosed is an indexable face milling cutting insert which comprises an insert body and a cutting body laminated on an upper surface of the insert body, and the insert body comprises multiple positioning side surfaces, an upper plane, and a positioning bottom surface; a projection of an edge of the positioning bottom surface, or an extension line thereof, on a rake face is intersected with a corresponding edge of the rake face, or an extension line thereof, to form a surface deflection angle and multiple flank faces are arranged between the rake face and the multiple positioning side surfaces, so as to avoid damaging the positioning side surfaces when a cutting edge is sharpened, thereby ensuring stability and long-term effect of a positioning reference, and a face cutting milling and a wiper face milling are applicable to a same face milling insert retaining slots.

A cutting insert includes a main surface formed in a substantially parallelogram shape and having a pair of acute angle corner portions and a pair of obtuse angle corner portions, a seating surface that faces a side opposite to the main surface, a side surface that connects the main surface and the seating surface to each other, a corner cutting edge disposed in the acute angle corner portion, and a main cutting edge and a subsidiary cutting edge which are respectively disposed in a pair of side ridge portions of the main surface located each other across the acute angle corner portion. A mounting hole into which the fixing member is inserted penetrates the main surface and the seating surface. The main cutting edge is inclined at an inclination angle equal to or larger than 8° with reference to a plane perpendicular to an axial direction of the mounting hole.

A double-sided cutting insert for milling has a first cutting edge formed at a transition from a top side to a circumferential lateral surface and a second cutting edge formed at a transition from a bottom side to the circumferential lateral surface. A reference plane (R) runs normal to an axis of symmetry (S). The cutting edges have main cutting edge portions and face cutting edge portions arranged in alternation, which extend between raised cutting corners and lowered cutting corners. The circumferential lateral surface has face free surfaces, which extend along the face cutting edge portion and which approach the axis of symmetry (S) with increasing distance from the associated face cutting edge portion. The circumferential lateral surface has main free surfaces, which extend along the main cutting edge portion and which move farther away from the axis of symmetry with increasing distance from the associated main cutting edge portion.

The present disclosure provides a cutting insert that is economical and can be stably fixed to a tool body. A first edge line (10R) of a cutting insert (2) is a rectangle having a first side (11) and a third side (13) as long sides and a second side (12) and a fourth side (14) as short sides. Cutting edges are formed at the first side (11), the second side (12) and the third side (13); on the other hand no cutting edge is formed at the fourth side (14). At a second edge line (20R) having the same shape as the first edge line (10R), a sixth side (22) where a cutting edge is formed is opposite to the fourth side (14), and an eighth side (24) where a cutting edge is not formed is opposite to the second side (12). A peripheral side surface (30) includes a fourth side surface (34) facing the fourth side (14) and the sixth side (22). The fourth side surface (34) extends from a first end surface (10) to a second end surface (20) and is inclined in a direction from the second side (12) to the fourth side (14).

A cutting insert has two opposing end surfaces interconnected by a peripheral side surface, the peripheral side surface having two major side surfaces and two minor side surfaces. Major edges are formed at the intersection of the major side surfaces and the end surfaces. Each end surface has two diagonally opposed raised corners and two diagonally opposed lowered corners with respect to a median plane, each raised corner adjoining one of the major edges at a first major point and each lowered corner adjoining one of the major edges at a third major point. In a major side view, each major edge has an associated first imaginary straight line containing its first and third major points, and an elevated edge portion located on one side of the first imaginary straight line. The cutting insert is removably secured in a rotary cutting tool.

In an end mill body made of ceramic, a corner R rake face is formed in such a manner as to contain a point B and at least a region B, not a region A located on a side toward an end cutting edge. In other words, a first end portion of a cutting edge on a peripheral edge portion of the corner R rake face is formed on a peripheral edge of the region B of a corner R cutting edge, and a second end portion of the cutting edge reaches at least the point B. As a result, partial breakage of the corner R cutting edge is unlikely to occur in the course of cutting. That is, since the corner R rake face is formed in such a manner as to start from the first end portion located apart from a point A, which is the intersection of the end cutting edge and the corner R cutting edge, and such that the second end portion reaches the point B, a large cutting load is unlikely to be imposed on the starting point of the corner R rake face. Therefore, the corner R cutting edge is unlikely to be chipped.