A cutting insert includes a cutting edge having an involute-curve approximate shape. A cutting edge is formed so as to wholly take on a first curved shape with a first curvature radius when the cutting insert is viewed from the end surface, and is formed so that a large part of the cutting edge takes on a second curved shape with a second curvature radius when the cutting insert is viewed from the side surface.

A double-sided tangential cutting insert comprising a pair of cutting rake faces, a pair of major side surfaces and a pair of opposing minor side faces each having a twisted convex shape. Each of the cutting rake faces is defined between a pair of main cutting edges, a pair of full nose cutting edges, and a pair of opposing convex minor cutting edges. Each of the minor side faces is defined between one of the convex minor cutting edges at one of the rake faces and one of the convex minor cutting edges at the other one of the rake faces wherein, at each minor side face, a ridge line interconnects an apex of the convex minor edge at the one of the rake faces and an apex of the convex minor cutting edge at the other one of the rake faces. Other variants and embodiments are broadly contemplated herein.

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.

An insert includes a rake angle set corresponding to the hardness of a material to be cut and that can suppress an increase in the material cost even when the strength of a cut edge section is increased. The insert has a polygonal shape and includes a cutting edge portion on at least one side of the polygonal shape. The cutting edge portion includes a rake face having a convex formed on one of opposite surfaces in the thickness direction a flank face having a concave formed on a surface intersecting with the one surface in the thickness direction and a concave cutting edge that is formed between the rake face and the flank face.

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.

Provided is a cutting insert that can suppress damage of a corner cutting edge. The cutting insert has an approximately polygonal shape, and is constituted of a main cutting edge and a corner cutting edge connected to the main cutting edge. The cutting insert includes: a first side face portion that is connected to the main cutting edge, has a negative clearance angle, and is formed such that height thereof increases gradually in a direction of approaching the corner cutting edge; and a second side face portion that is connected to the corner cutting edge, has a negative clearance angle, and has height that is greater than the first side face portion.

Railway wheel milling tool system including a railway wheel truing cutters and tangential railway wheel milling inserts are disclosed. The tangential milling inserts have at least four indexable cutting edges, each with a central wiper cutting edge segment between two convex cutting edge segments. The milling inserts may allow both the flat portion and curved portion of a railway wheel to be machined with an improved surface finish. The railway wheel truing cutters comprise a plurality of insert pockets structured and arranged to receive the tangential railway wheel milling inserts.

Large diameter edges formed in arc shapes having curvature radii larger than a ball radius are provided. This allows improving surface roughness of a machined surface by cutting of a planar surface with the respective large diameter edges compared with cutting of a planar surface with a ball end cutting edge formed in an arc shape having a single curvature radius. Further, since the respective large diameter edges are formed in the arc shape, compared with cutting of a curved surface with linear cutting edges, surface roughness of a machined surface can be improved by cutting a curved surface with the respective large diameter edges. Accordingly, a pick feed during the cutting of the planar surface and the curved surface with the respective large diameter edges can be increased, and therefore machining efficiency in the cutting of both of the planar surface and the curved surface can be improved.

A cutting insert has an upper surface, a lower surface, a side surface connecting the upper and lower surfaces. An intersecting edge between the upper surface and the side surface is provided with a cutting edge. The cutting edge has, in order, a second major cutting edge, a first major cutting edge, a corner cutting edge connected to these major cutting edges, and a flat cutting edge. An obtuse interior first angle (θ) is formed by the second and first major cutting edges. A interior second angle (α) formed by the flat cutting edge and the first major cutting edge is larger than an interior third angle (β) formed by the flat cutting edge and the second major cutting edge. A land is provided adjacent to the first major cutting edge, a width of the land increasing toward the first corner cutting edge.

A double-sided cutting insert for milling which has eight main cutting edges and eight wiper edges. The cutting insert includes top and bottom faces and four side faces. Each side face includes first and second sub-faces inclined with respect to each other. The first sub-face has a main cutting edge adjacent to the top face and a wiper edge adjacent to the bottom face. The second sub-face has a wiper edge adjacent to the top face and a main cutting edge adjacent to the bottom face. The wiper edge of the second sub-face is inclined inwardly relative to the cutting insert with respect to the main cutting edge of the first sub-face. The wiper edge of the first sub-face is inclined inwardly relative to the cutting insert with respect to the main cutting edge of the second sub-face.