A disposable cutting insert locking structure includes a shank and a disposable cutting insert. An insert seat is disposed at a front end of the shank. The insert seat has a positioning portion. The positioning portion has a triangular shape. The positioning portion is provided with a screw hole. The disposable cutting insert has a bottom. The bottom is formed with a positioning recess. A through hole is defined in the positioning recess for a screw to be inserted from a top of the disposable cutting insert and screwed to the insert seat.

A combined structure of an arbor and an arbor seat, including: an arbor, having a first assembling portion which has at least one first hole, each first hole having a first central axis; an arbor seat, having a second assembling portion which is disposed in the axial direction, and the first assembling portion and the second assembling portion being insertably connected with each other, the second assembling portion having at least one second hole which has a second central axis, when the first and second assembling portions are connected with each other in the axial direction, each second central axis is noncoaxial and nonoverlapped with the at least one first central axis; and wherein at least one said fastener is inserted into one said first hole and one said second hole, and urges one said first hole and one said second hole in axially opposite directions.

A cutting insert and a shoulder milling tool are disclosed. The cutting insert includes a surface-wiping secondary cutting edge inclined in relation to a median plane of the cutting insert such that a distance to the median plane decreases in a direction toward a corner cutting edge. The corner cutting edge, as seen in a side view along the median plane and towards a main cutting edge, has a concave curve.

A reversible cutting insert for milling including opposing and identically or substantially identically top and bottom surfaces interconnected by a continuous peripheral side surface, with a median plane located between the top and bottom surfaces and intersecting the side surface, and an insert axis perpendicular to the median plane about which the cutting insert is indexable. Each top and bottom surface is limited by a circumferential cutting edge intersecting the side surface, the circumferential cutting edge in a top view having the shape of a truncated equilateral triangle. Each circumferential cutting edge includes three analogous sets of cutting edges exhibiting three-fold rotational symmetry about the insert axis. A first cutting edge portion intersects a first support plane.

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.

According to the present disclosure, a cutting insert includes an upper surface having a polygonal shape and includes a corner, a side surface adjacent to the upper surface, a cutting edge and a protrusion. The cutting edge is located at a ridge part in which the upper surface intersects with the side surface and includes a corner part located at the corner. The protrusion is located on the upper surface. The protrusion includes a first protrusion on a bisector of the corner in a top view. The protrusion further includes a second protrusion adjacent to the first protrusion in a direction orthogonal to the bisector. The second protrusion is closer to the corner than the first protrusion in the top view.

A cutting insert having two opposing end surfaces, two identical opposing major side surfaces and two identical opposing minor side surfaces. Each end surface has four corners with two lowered corners and two raised corners, the two lowered corners being diagonally opposite each other, the two raised corners being diagonally opposite each other. The cutting insert also includes a major cutting edge formed at an intersection of each major edge and the end surface. A first section of the major cutting edge proximate the raised corner constitutes a leading end of the major cutting edge, and a second section of the major cutting edge proximate the lowered corner constitutes a trailing end of the major cutting edge. An angled margin only partially extends along the leading end of the major cutting edge and segments the major cutting edge.

A combined structure of an arbor and an arbor seat, including: an arbor, having a first assembling portion which has at least one first hole, each first hole having a first central axis; an arbor seat, having a second assembling portion which is disposed in the axial direction, and the first assembling portion and the second assembling portion being insertably connected with each other, the second assembling portion having at least one second hole which has a second central axis, when the first and second assembling portions are connected with each other in the axial direction, each second central axis is noncoaxial and nonoverlapped with the at least one first central axis; and wherein at least one said fastener is inserted into one said first hole and one said second hole, and urges one said first hole and one said second hole in axially opposite directions.

A cutting insert comprises: a first end surface and a second end surface which are opposed to each other; a peripheral side surface which extends so as to connect the first end surface and the second end surface; a first cutting edge which is arranged in an intersecting edge between the first end surface and the peripheral side surface; and a second cutting edge which is arranged in an intersecting edge between the second end surface and the peripheral side surface. The peripheral side surface includes a first flank which is connected to the first cutting edge and an intermediate peripheral side surface portion which is arranged closer to the second end surface than the first flank. The first flank extends in a direction perpendicular to the first end surface. The intermediate peripheral side surface portion protrudes outward from the first flank.

A single-sided three-way indexable milling insert for 90 shoulder milling operations, includes a positive basic shape, a rake surface, a peripheral surface including side abutment surfaces, a base bearing surface and a screw hole connecting the rake and base bearing surfaces. The insert has three main cutting edges which lie along an imaginary equilateral triangle. A material volume V.sub.F of the cutting insert and a void volume V.sub.S of the insert's screw hole fulfill the condition V.sub.S/V.sub.F0.30.