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.

The present invention provides a tool body (20) for use in an indexable rotary cutting tool, the tool body (20) having a rotational axis and a substantially cylindrical shape. Spiral grooves (28) are formed so as to extend from a base end side of the tool body to a leading end side in a peripheral surface (23) of the tool body. The spiral grooves (28) each have a plurality of insert seats (30) formed so as to be shifted from each other from the base end side toward the leading end side. The insert seats (30) each have a bottom surface (31) and first and second side surfaces (32, 33) that extend so as to intersect with the bottom surface (31). The first side surface (32) faces the base end side of the tool body (20), and the second side surface (33) faces the leading end side of the tool body (20) and is located on the base end side with respect to the first side surface (32). In at least one insert seat (30) located closer to the base end side with respect to an insert seat (30) located closest to the leading end side of the tool body (20), a length (L1) of the first side surface (32) is longer than a length (L2) of the second side surface (33).

An indexable roughing end mill having a peripheral surface provided with a plurality of spiral grooves. When the positions of cutting inserts (40) arranged in each spiral groove (28) are defined as a first segment to an n.sup.th segment from a leading end surface (22) side of a tool body (20) toward a base end surface (21) side, all of the angles 1 . . . m between lines connecting a rotational axis (O) and the cutting inserts (40) in the first segments of the respective spiral grooves (28) are different from each other, as viewed from the leading end, and an angle (t) between the cutting insert (40) in the first segment and the cutting insert (40) in the uppermost n.sup.th segment in a spiral groove 28 is different from any of the angles 1 . . . m between the lines, as viewed from the leading end.

A rotary cutting tool has a plurality of circumferentially spaced grooves, each having a plurality of cutting inserts mounted. Each cutting insert has a wave-shaped major cutting edge, a corner cutting edge, and a minor cutting edge. The cutting inserts are arranged such that, the phases of the waves of the rotational trajectories formed by the cutting inserts that are adjacent to each other in a direction along the tool rotational axis coincide with each other in one groove. Also, the rotational trajectories of at least part of cutting edge portions of at least some cutting inserts are overlapped with each other in the direction of the tool rotational axis. Accordingly, even when the cutting edge portion is used as a major cutting edge and as an inner cutting edge, it is still possible to reduce cutting load and suppress breakage.

An indexable cutting insert, arranged for being mounted in an insert seat of a tool body of a shoulder milling tool, includes a triangular top surface, a triangular bottom surface, and three circumferential surfaces extending between the top and bottom surface. On each side of the cutting insert an individual one of the three circumferential surfaces extends along an edge of the triangular top surface and along an edge of the triangular bottom surface. The cutting insert includes at each of the top and bottom surfaces three cutting corners, three main cutting edges and three minor cutting edges. Each cutting corner connects a main cutting edge and a minor cutting edge. Each of the cutting corners, each of the main cutting edges and each of the minor cutting edges are provided at an intersection between the top surface or the bottom surface and one of the circumferential surface.

A reversible and indexable tangential milling insert includes two major surfaces and a peripheral surface which extends therebetween. The milling insert includes a mid-plane (M) located midway between the major surfaces, and an insert clamping bore with a central bore axis (H). The peripheral surface includes three side surfaces, each of which includes exactly two cutting portions, two relief portions and two minor abutment surfaces located on opposite sides of the mid-plane (M), each continuously extends between respective cutting portion and relief portion. Each cutting portion includes a major cutting edge, a minor cutting edge, and a corner cutting edge. In a cross section along a first imaginary plane perpendicular to the bore axis (H), each minor abutment surface is concavely curved, and on each side surface, the minor abutment surfaces converge outwardly.

A thread milling cutter (1) includes an integrally formed thread milling tool (10) having a rotational axis (S), a shank portion (24) and a forward cutting portion (34). The cutting portion (34) has at least five insert pockets (42) recessed therein with at least one insert pocket (42) being devoid of an associated support protrusion (46), allowing different insert placements for different thread pitches.

A double-sided milling cutting insert has a first cutting edge disposed at an intersection of a top side and a side surface and a second cutting edge disposed at an intersection of a bottom side and the side surface. Each of the first and second cutting edges contains three cutting edge portions which are useable by indexing. The cutting edge portions each have a cutting corner, a main cutting edge adjacent to one side of the cutting corner, and a wiper edge adjacent to the other side of the cutting corner. The main cutting edge and the wiper edge are each inclined towards a reference plane with increasing distance from the cutting corner such that the first and second cutting edges have the largest distance to the reference plane in the regions of the cutting corners. The side surface has main clearance surfaces, secondary clearance surfaces, and curved corner surfaces.

A cylindrical tool body has a peripheral surface provided with one or more spiral grooves extending from a base end side to a leading end side. The grooves each have a plurality of insert seats which are shifted relative to one another from the base end side toward the leading end side. The insert seats each have a bottom surface, a first side surface of length L1, and a second side surface of length L2. The first side surface faces the tool body's base end side, and the second side surface faces the tool body's leading end side and is located on the base end side with respect to the first side surface. In at least one insert seat located closer to the base end side than an insert seat located closest to the tool body's leading end side, the first side surface is longer than the second side surface.

An insert, a housing, and a power skiving assembly each configured for use in a power skiving process is provided. The insert includes multiple cutting edges such that when one of the cutting edges is no longer suitable for use in a power skiving process, an orientation of the insert with respect to the housing can be changed so that another of the multiple cutting edges is aligned with a work piece upon which the power skiving process is being performed.