A cutting insert suitable for a small-diameter milling tool is provided. A cutting insert has a rake face, a bottom surface, a circumferential side surface, and a through hole. A first ridgeline at which the rake face and the circumferential side surface intersect each other includes a first main cutting edge, and a first corner cutting edge connected to a tip of the first main cutting edge. The bottom surface includes a first bottom surface that comes closer to the rake face gradually toward a side at which the first main cutting edge is located when viewed from a central axis of the through hole, and a second bottom surface that comes closer to the rake face gradually toward a side opposite to the first main cutting edge when viewed from the central axis. A distance between a virtual intersection line, at which a first virtual surface formed by extending the first bottom surface and a second virtual surface formed by extending the second bottom surface intersect each other, and the first main cutting edge decreases from a tip side, at which the tip of the first main cutting edge is located, toward an end side, at which an end opposite to the tip is located, in an extending direction of the first main cutting edge.

A cutting insert includes an upper surface, a lower surface opposite to the upper surface, a first side surface and a second side surface configured to connect the upper surface and the lower surface, a mounting hole formed to penetrate the upper surface and the lower surface, a first cutting edge formed at an edge of the upper surface that meets the first side surface, and a second cutting edge formed at an edge of the upper surface that meets the second side surface. The lower surface includes a ridge portion, and a first inclined surface and a second inclined surface positioned on both sides of the ridge portion as a boundary. When looking at the lower surface, the first inclined surface and the second inclined surface have asymmetric shapes with respect to the ridge portion.

Indexable insert has a non-rectangular parallelogram shape with nearly rhombic basic shape and an imaginary intermediate plane spanned by four corners of an imaginary rhombus with sides running at a distance away from the upper side and the underside along the peripheral lateral surface in a plane such that each equivalent cutting edge has the same variation of distance and angle from the intermediate plane. Two diagonally opposing corners of both the upper side and the underside each have a greater distance from the intermediate plane than do the respective diagonally opposing corners of the upper side and the underside lying therebetween, and the diagonally opposing corners of the upper side and of the underside are shifted parallel to the intermediate plane and, as viewed in a plan view onto the intermediate plane, in mutually opposite directions away from the associated diagonals of the rhombus spanning the intermediate plane.

A tool body having an insert seat and a cutting tool which allow a cutting insert to be stably held are provided. A tool body according to the present invention is a tool body having an insert seat for mounting a cutting insert on the tool body, wherein the insert seat has a base surface and a side wall surface which extends so as to intersect with the base surface. The base surface has a contact surface and a contact projected part which come into contact with the cutting insert. A contact part of the contact surface is comprised of a surface, and a contact part of the contact projected part has a linear shape or a point shape.

A cutting insert has opposing first and second end surfaces, and a peripheral side surface (connecting the end surfaces. A central axis penetrates the two end surfaces. The peripheral sure surface includes an outwardly inclined first side surface part related to a major cutting edge and a second side surface part related to a minor cutting edge. The outwardly inclined first side surface part gradually extends outward from the cutting insert, heading from the first end surface to the second end surface. When a second virtual plane, which is substantially perpendicular to the central axis and passes through the major cutting edge, is defined, an inwardly inclined part, on a back side of the cutting edge, of the second end surface is inclined so as to become more distant from the second virtual plane, heading from the outwardly inclined first side surface part to the central axis.

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.

Provided is a milling tool that allows a life of a tool main body to be elongated. The milling tool includes a replaceable cutting insert and a tool main body in which at least one insert seat that fixes the cutting insert is provided on a distal end side. The tool main body has a reinforcing wall covering at least a portion of the cutting insert when the cutting insert that is in a state of being fixed to the tool main body is viewed from the distal end side.

A cutting insert suitable for a small-diameter milling tool is provided. A cutting insert has a rake face, a bottom surface, a circumferential side surface, and a through hole. A first ridgeline at which the rake face and the circumferential side surface intersect each other includes a first main cutting edge, and a first corner cutting edge connected to a tip of the first main cutting edge. The bottom surface includes a first bottom surface that comes closer to the rake face gradually toward a side at which the first main cutting edge is located when viewed from a central axis of the through hole, and a second bottom surface that comes closer to the rake face gradually toward a side opposite to the first main cutting edge when viewed from the central axis. A distance between a virtual intersection line, at which a first virtual surface formed by extending the first bottom surface and a second virtual surface formed by extending the second bottom surface intersect each other, and the first main cutting edge decreases from a tip side, at which the tip of the first main cutting edge is located, toward an end side, at which an end opposite to the tip is located, in an extending direction of the first main cutting edge.

Provided is a milling tool that allows a life of a tool main body to be elongated. The milling tool includes a replaceable cutting insert and a tool main body in which at least one insert seat that fixes the cutting insert is provided on a distal end side. The tool main body has a reinforcing wall covering at least a portion of the cutting insert when the cutting insert that is in a state of being fixed to the tool main body is viewed from the distal end side.

A cutting body rotatable about a tool axis has an insert receiving pocket with a seat surface at an axial forward end thereof. The seat surface has a plurality of abutment elements, including an axial abutment element having an axially forward facing abutment surface and at least one radial abutment element. In a top view of the insert receiving pocket, the axially forward facing abutment surface forms an external acute clamping angle with a radially outward facing pocket wall. A rotary cutting tool includes the cutting body, and a cutting insert removably secured in the insert receiving pocket, having a base surface in contact with the seat surface. The at least one radial abutment element occupies or is occupied by at least one radial abutting element of the base surface, and the axially forward facing abutment surface is in contact with an axial abutting surface of the base surface.