An end mill, preferably made of solid carbide, with a fastening section and a cutting area, in which the cutting area is formed by a core and three or four cutting edges running helically around the axis of rotation of the end mill and arranged around core; each of which has a peripheral main cutting edge and a secondary cutting edge on a face of the cutting area. On the face of the cutting area at least one point thinning of core is provided between two adjacent cutting edges. In order to create end mills that are simple to manufacture and optimized for drilling, the point thinning has an angle of 30 to 40 relative to the axis of rotation of the end mill.

The present disclosure relates to a gear cutting machine for gear cutting a workpiece, in particular a toothed wheel, by form milling having at least one cutter head for mounting at least one end mill, wherein the cutter head or the end mill and/or the workpiece mount are adjustable and the end mill axis can be aligned approximately parallel to the machined tooth flank of the clamped workpiece, and wherein the cutter axis can be applied to the flank contour and the end mill has an outer contour corresponding to the flank contour.

The purpose of the present invention is to perform machining on a double-curved surface to have good finished surface characteristics while achieving high speed feeding. An end mill (2) is provided with a bottom blade (2A) formed in a curved convex and circular arc shape, and a radius blade (2B) located at the edge and formed in a circular arc shape. The bottom blade (2A) has a region where a blade part is not formed on the axis of the end mill (2), and the end mill (2) is further provided with a center blade (2C) in the region of the bottom blade (2A). The center blade (2C) is formed in a circular arc shape with a radius smaller than that of the circular arc part of the bottom blade (2A).

A milling tool includes a first cutting portion having a first and a second cutting edge extending at the periphery of the first cutting portion along, or following a helical path around, a longitudinal axis of the milling tool. The first and second cutting edges are arranged such that, when the milling tool is rotated around its longitudinal axis, they form respective first and second lines of intersection in a central plane containing the longitudinal axis, wherein the first and the second lines of intersection are arcuate. The extension of the first cutting edge is different from the extension of the second cutting edge such that the first line of intersection is different from the second line of intersection.

A milling tool includes a main body and a plurality of cutting inserts with respective cutting edges. The main body has an end face and a barrel-shaped curved lateral face. A first group of the plurality of cutting inserts are fastened on the end face, a second group of the plurality of cutting inserts are fastened on the barrel-shaped curved lateral face, and the respective cutting edges describe a barrel shape. Each one of the plurality of cutting inserts may be designed as an indexable insert.

Provided is a structure for improving accuracy in attaching a cutting tool to a body and making it possible to increase the number of blades while the cutting tool is mounted on the body. A cutting insert 1 includes: an upper surface 10 that has a shape with a lengthwise direction LD and a widthwise direction SD; a lower surface that is located opposite to the upper surface 10; a peripheral side surface 30 that is formed so as to connect the upper surface 10 and the lower surface; cutting edges 51 and 52 that are respectively formed on an intersecting ridge line of the upper surface 10 and the peripheral side surface 30, and on an intersecting ridge line of the lower surface and the peripheral side surface 30, and each have a curved ridge line that extends in a lengthwise direction thereof; and a through hole 60 that penetrates from the upper surface 10 to the lower surface. End surfaces 31 and 32 located in the lengthwise direction LD of the upper surface 10 and the lower surface, of the peripheral side surface 30, are respectively inclined with respect to the upper surface 10 and the lower surface, and are parallel to each other. A reference surface 33 that is located opposite to the cutting edges 51 and 52, of the peripheral side surface 30, is a flat surface that is orthogonal to the upper surface 10 and the lower surface.

An example milling bit comprises a shank and a working sector comprising a cutting anterior part, which is a portion of a hollow sphere, a cutting posterior part fixed to the shank and located between the shank and the spherical anterior part, at least one cutting tooth extending along an entire length of the working sector with a cutting edge, and at least one flute to the cutting tooth extending along length of the working sector following the path of the cutting edge. The spherical anterior part of the working sector is hollow and at least one cutting tooth in the anterior cavity region has a shape of a spherical shell element.

The present disclosure provides a cutting tool that comprises: an end cutting edge that is formed so as to extend radially from the central axis side; a peripheral edge that forms a pair of cutting edges with the end cutting edge; and a chip discharge groove provided around the central axis. The chip discharge groove is formed by two or more grooves that include at least a major groove and a minor groove and have different helix angles from each other. The major groove that forms the peripheral edge on an edge between a peripheral side surface of the cutting tool and such major groove has a helix angle that is the smallest helix angle, and the minor groove that is in contact with the major groove and arranged with its phase shifted forward with respect to the major groove in a tool rotating direction has a helix angle that is greater than the helix angle of the major groove.

An example milling bit comprises a shank and a working sector comprising a cutting anterior part, which is a portion of a hollow sphere, a cutting posterior part fixed to the shank and located between the shank and the spherical anterior part, at least one cutting tooth extending along an entire length of the working sector with a cutting edge, and at least one flute to the cutting tooth extending along length of the working sector following the path of the cutting edge. The spherical anterior part of the working sector is hollow and at least one cutting tooth in the anterior cavity region has a shape of a spherical shell element.