Cutting inserts are disclosed having four cutting edges and milling tools comprising the cutting inserts installed in pockets on a rotatable cutting tool holder. The cutting inserts comprise a front face, a rear face and four side faces extending between the front and rear faces. A cutting edge is provided at the intersection of the front face and each side face. Each cutting edge comprises a plurality of cutting edge segments, including a facet cutting edge that forms the flat surface of a workpiece being milled, and a straight lead cutting edge that extends at an angle away from the facet cutting edge. The lead cutting edge angle is selected to provide effective milling of the workpiece at entry. The cutting inserts have side seating surfaces that allow the inserts to be more stably supported in cutting insert pockets.

A cutting insert includes a top face and a bottom face parallel to the top face. Four side faces and four corner faces extend between the top and bottom faces. At least one cutting edge is formed at an intersection of the top face and at least one of the corner faces and two of the side faces connected to the corner face. The top face forms a rake surface, while an upper part of the corner face and the two side faces form a relief surface connected to the cutting edge. In order to reduce the cycle time for crank shaft milling, the cutting insert has two diagonally opposed corners including an acute angle between 70° and 85°. At least one of the acute angled corners including the corner face providing a corner cutting edge. A disc milling tool including such cutting inserts is also provided.

A cutting insert has an upper surface having a long side, a short side, a lower surface, a lateral surface and a through hole. The lateral surface has a first lateral surface. The first lateral surface has a first plane that is overlapped with a central axis of the through hole in a front view and is parallel to the central axis, a second plane that is located closer to the short side than the first plane and is parallel to the central axis, a third plane that is located more away from the short side than the first plane and is parallel to the central axis, and a first inclined surface that is located between the second plane and the upper surface and comes closer to the central axis as coming closer to the long side. The first inclined surface is located away from the first plane.

A cutting insert of the present invention comprises: an upper surface and a lower surface; first and second lateral surfaces; first and second cutting edge parts; and corner cutting edges, wherein the first cutting edge part includes: a first main cutting edge for forming one end at a portion spaced farthest away from the corner cutting edge; a first sub-cutting edge connected to the corner cutting edge; and a first auxiliary cutting edge for connecting the first main cutting edge and the first sub-cutting edge so as to form a step between the same, and the first sub-cutting edge and the corner cutting edge form one straight line when viewed toward the first lateral surface, and are inclined upward in the direction opposite to the direction toward the lower surface while gradually going in the direction toward the second cutting edge part.

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 includes an upper surface including a first upper cutting edge and a second upper cutting edge, a lower surface including a first lower cutting edge and a second lower cutting edge, and a side surface. The side surface includes a first surface extending from the second upper cutting edge, a second surface extending from the first lower cutting edge, a third surface extending from the first upper cutting edge, and a fourth surface extending from the second lower cutting edge. The first surface and the fourth surface are parallel to a central axis. The second surface is inclined so as to depart from the central axis as going from the lower surface toward the upper surface. The third surface is inclined so as to depart from the central axis as going from the upper surface toward the lower surface.

The present invention relates to a cutting device and a chamfering machine comprising the same, and according to one aspect of the present invention, a cutting device for use in a chamfering process of a film laminate is provided, in which the cutting device comprises a rotating wheel having a rotation center; and a cutting bite comprising a main body mounted on the rotating wheel and a cutting tip provided on the main body and provided to perform chamfering of the film laminate by rotating the rotating wheel, wherein the cutting bite is mounted on the rotating wheel such that the central axis of the cutting tip is inclined at a first angle with respect to the tangential direction of a rotation locus of the cutting bite formed by rotating the rotating wheel.

A cutting insert has an upper surface, a lower surface, a side surface connected to each of the upper surface and the lower surface, and a cutting edge having sequentially a corner cutting edge, a first straight cutting edge, a second straight cutting edge, and a third straight cutting edge, which are located along an intersection of the upper surface and the side surface and intersect one another at an obtuse angle. The upper surface has a first inclined surface extending along the first straight cutting edge, a second inclined surface extending along the second straight cutting edge, and a third inclined surface extending along the third straight cutting edge. An inclination angle of the second inclined surface with respect to the lower surface is larger than an inclination angle of each of the first inclined surface and the third inclined surface with respect to the lower surface.

A cutting insert for a rotary cutting tool has a second surface that includes a second seating surface having a shape of a flat surface. The first cutting edge has a first main cutting edge portion and a first sub cutting edge portion. The second cutting edge has a second main cutting edge portion and a second sub cutting edge portion. When viewed in a direction from the first surface toward the second surface, at least a portion of the second sub cutting edge portion is located outside the first main cutting edge portion, and at least a portion of the first sub cutting edge portion is located outside the second main cutting edge portion. When viewed in the direction from the first surface toward the second surface, each of the first sub cutting edge portion and the second sub cutting edge portion has a shape of a curved line.

A plurality of cutting bodies each having a cutting edge are arranged on the main body of a machining tool. During operation, the plurality of cutting bodies rotate in a direction of rotation which runs around an axis of rotation. Each cutting edge has exactly one reference point. The reference points are mutually spaced in the direction perpendicular to the direction of rotation. Reference points of cutting bodies that are directly adjacent in the direction perpendicular to the direction of rotation are arranged with mutual angular spacings with respect to the axis of rotation. The spacings are integer multiples of angle values which lie in an angle range of +/−5° with respect to the golden angle. The sum of the golden angle and an opposite angle produces the round angle. The ratio of golden angle to opposite angle is equal to the ratio of opposite angle to round angle.