Sumitomo Electric Hardmetal Corp.

Yusuke Koike

Atsuhiko Maeta

Kouki Matsubara

Yasuyuki Kanada

Tomoyuki Fukuyama

Yoshinari Nagami

Katsuya Nakakihara

Keiji Kinoshita

Yuta Morisaki

Shota Tsujimoto

A cutting insert according to the present disclosure includes a first surface, a second surface, a side surface, and a cutting edge. The first surface has a rake face continuous to the cutting edge. The cutting edge has a corner cutting edge, a flat cutting edge, and a main cutting edge. The rake face has a first rake face portion, a second rake face portion, and a third rake face portion, the first rake face portion being continuous to the flat cutting edge, the second rake face portion being continuous to the main cutting edge, the third rake face portion being continuous to the corner cutting edge and being located between the first rake face portion and the second rake face portion. The rake face is provided with a level difference portion.

Cutting insert

A cutting edge has a corner cutting edge, a flat drag, and a main cutting edge. The rake surface has a first rake surface portion, a second rake surface portion, and a third rake surface portion. The first rake surface portion has a first inclined surface inclined at a first angle. The second rake surface portion has a second inclined surface inclined at a second angle greater than the first angle. The first end portion and the second end portion are higher than the reference surface in a direction perpendicular to the reference surface, and the main cutting edge extends so as to intersect the reference surface when viewed in a direction parallel to the reference surface. A first step portion rising from the third rake surface portion and continuous with the first rake surface portion is provided on the rake surface.

The cutting edge has: a corner cutting edge; a flat cutting edge continuous to a first end portion of the corner cutting edge; and a main cutting edge continuous to a second end portion of the corner cutting edge opposite to the first end portion of the corner cutting edge. The rake face has: a first rising surface portion; and a first rake face portion continuous to the first rising surface portion and located opposite to the corner cutting edge when viewed from the first rising surface portion. When viewed in a direction perpendicular to the reference surface, the first boundary includes a first line segment extending, from one of the flat cutting edge and the corner cutting edge, in a direction crossing a straight line extending along the main cutting edge.

A second distance is longer than a first distance and a value obtained by dividing the third distance by the fourth distance is more than or equal to 0.5 and less than or equal to 0.8 when it is assumed that the first distance represents a distance between the cutting edge and the mounting surface in a direction perpendicular to the rake face, the second distance represents a distance between the mounting surface and a boundary portion between the rising portion and the flat portion in the direction perpendicular to the rake face, the third distance represents a distance between the boundary portion and a tip of the cutting edge in a direction parallel to the rake face, and the fourth distance represents a distance between the second discharging opening portion and the tip of the cutting edge in the direction parallel to the rake face.

Cutting insert and milling tool

A cutting tool including: a tool body () provided with an insert support seat () including a major seat surface () that supports a bearing surface of a cutting insert, a plurality of seat side surfaces () that supports side surfaces of the cutting insert at different positions, and a thinned portion () continuous with the major seat surface and the seat side surfaces; and a cutting insert attached to the insert support seat, wherein a ridge at a position where the major seat surface and the thinned portion intersect, a ridge at a position where the seat side surface and the thinned portion intersect, and a ridge at a position where the thinned portions continuous with each other intersect are each formed of a convex arc curved surface.

Cutting tool and tool body

A cutting insert includes a first surface and a second surface each of which is polygonal and that face away from each other; a side surface that is continuous with the first surface and a side surface that is continuous with the second surface; a cutting edge formed along each of a ridge where the first surface and the side surface intersect and a ridge where the second surface and the side surface intersect; a bearing surface formed in each of a part the first surface and a part of the second surface adjacent to an insert center, the bearing surfaces disposed parallel to each other; and a recessed portion that separates the side surface that is continuous with the first surface from the side surface that is continuous with the second surface. The cutting edge includes three corner edges, a first cutting edge, and a second cutting edge, the first and second cutting edges being continuous with each other and located between each pair of the corner edges. A length of the first cutting edge is greater than that of the second cutting edge, an end portion of the first cutting edge adjacent to one of the corner edges is at a position higher than the bearing surface, and an end portion of the first cutting edge opposite to the end portion adjacent to the corner edge is at a position lower than the bearing surface. Each of the first surface, the second surface, and a cross section of the recessed portion has such a shape that outlines of the shape before and after rotation of the insert by 120&#xb0; around the insert center are coincident with each other. The first surface and the second surface have the same shape, and the second cutting edge of the second surface is located at a corner at which the first cutting edge of the first surface is located.

Growing community of inventors

Itami, Japan

Yusuke Koike