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 front and back chamfering rotary milling cutter includes a cutter body including an insert pocket and a star-shaped indexable cutting insert releasably retained in the pocket. The cutting insert has star-shaped upper and lower surfaces connected by a peripheral surface intersecting each of the upper and lower surfaces. The cutting insert includes a plurality of circumferentially alternating inner and outer corner portions. A cutting portion is defined by each outer corner portion together with an adjacent first inner corner portion rotationally forward thereof and an adjacent second inner corner portion located rotationally rearward thereof. Each cutting portion includes a front chamfering cutting edge extending from the outer corner portion to the first inner corner portion and a back chamfering cutting edge extending from the outer corner portion to the second inner corner portion.

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.

A cutting insert in a non-limiting aspect of the present disclosure may include an upper surface having a polygonal shape and including a first side, a lower surface, and a lateral surface. The lateral surface may include a first lateral surface located between the first side and the lower surface. The first lateral surface may include a first region that is flat. The first region may include a first central region, a first upper region and a first lower region. The first upper region may be located closer to the upper surface than the first central region, and may have a larger width than the first central region. The first lower region may be located closer to the lower surface than the first central region, and may be a larger width than the first central region.

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 has: an upper surface; a lower surface; a side surface, having a first surface and a second surface disposed opposite each other between the upper surface and the lower surface; and a first cutting edge. The lower surface has a plurality of slots extending from a side of the first surface to a side of the second surface. In addition, when viewed from a side of the lower surface, if the angle between a ridge line on which the upper surface and the first surface intersect and an imaginary extension line of the plurality of slots is defined as θ1, and the angle between a ridge line on which the lower surface and the first surface intersect and the imaginary extension line is defined as θ2, then θ2>θ1.

An indexable milling cutter includes a milling cutter body with a plurality of flutes and a plurality of seating surfaces adapted to mount a cutting insert thereon. The milling cutter body includes a plurality of coolant reservoirs in fluid communication with an adapter. In one aspect, each coolant reservoir lies along a circular intersection line of a coolant manifold. In another aspect, a longitudinal axis of each coolant reservoir is oriented at a non-zero angle, A, with respect to a central, longitudinal axis of the milling cutter. A plurality of coolant ducts in fluid communication with each coolant reservoir, each coolant duct having a smaller cross-sectional area than the coolant reservoir, provide multiple streams of coolant targeted at a plurality of specific critical cutting areas of the cutting insert.

A rotary cutting tool includes a cutting head having a plurality of insert-receiving pockets for radially mounting a first type of cutting insert in a first cutting region and for tangentially mounting a second type of cutting insert in a second cutting region. The first cutting region has a first length, L1, and the second cutting region has a second length, L2, that is greater in magnitude than the first length, L1. The two types of cutting inserts provides a hybrid cutting insert design in which the first type of cutting inserts provide an increased chip gash volume for effective chip evacuation, and the second type of cutting inserts provide an increased core diameter to minimize deflection of the rotary cutting tool.

The present disclosure provides a cutting device. The cutting device includes a shaft, two or more gussets, two or more radial cutting members, and a circumferential cutting member. The shaft extends from a first end to a second end. The two or more gussets include at least a first gusset and a second gusset extending radially away from the shaft. The two or more radial cutting members include at least a first radial cutting member axially supported by the first gusset and a second radial cutting member axially supported by the second gusset. The circumferential cutting member is axially supported by each of the first gusset and the second gusset.

The first cutting insert is attached to a first pocket. The second cutting insert is attached to a second pocket. The third cutting insert is attached to a third pocket. The first pocket has a first seat surface, a second seat surface, a third seat surface, and a first swarf discharging groove. The second pocket has a fourth seat surface, a fifth seat surface, a sixth seat surface, and a second swarf discharging groove. The third pocket has a seventh seat surface, an eighth seat surface, a ninth seat surface, and a third swarf discharging groove. In a cross section perpendicular to an axis, an angle formed between a straight line along the sixth seat surface and a tangent of the second swarf discharging groove at a boundary between the outer circumferential surface and the second swarf discharging groove is more than 90°.