Cutting insert and cutting tool on which same is mounted

Patent metadata

Field	Value
Publication number	US-11260461-B2
Application number	US-201816962041-A
Country	US
Kind code	B2
Filing date	Dec 6, 2018
Priority date	Jan 19, 2018
Publication date	Mar 1, 2022
Grant date	Mar 1, 2022

Abstract

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.

First claim

What is claimed is:

1. A cutting insert comprising an upper surface and a lower surface facing opposite directions to each other, and first and second lateral surfaces connecting the upper surface and the lower surface and being adjacent to each other, wherein the cutting insert comprises:
a first cutting edge part forming a boundary between the upper surface and the first lateral surface;
a second cutting edge part forming a boundary between the upper surface and the second lateral surface; and
a corner cutting edge connecting the first cutting edge part and the second cutting edge part,
wherein the first cutting edge part comprises:
a first main cutting edge 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 connecting the first main cutting edge and the first sub-cutting edge so as to form a step therebetween,

wherein the first sub-cutting edge and the corner cutting edge, when viewing the first lateral surface, form one straight line and are inclined upward in a direction opposite to a direction toward the lower surface while gradually going in the direction toward the second cutting edge part,
wherein the second cutting edge part comprises a second main cutting edge forming one end at a portion contacting the corner cutting edge, and when the upper surface is an X-Y plane and a Z-axis passes through a center of the upper surface, viewing the first lateral surface after rotating the first lateral surface by 45 degrees with respect to the Z axis reveals that the first sub-cutting edge, the corner cutting edge, and the second main cutting edge form one straight line section and are inclined upward in a direction opposite to a direction toward the lower surface while gradually going in the direction toward the other end of the second main cutting edge, and
wherein the first lateral surface comprises:
an upper clearance surface contacting the first cutting edge part;
a lower clearance surface contacting the lower surface; and
an intermediate clearance surface connecting the upper clearance surface and the lower clearance surface.

2. The cutting insert according to claim 1 , wherein the first cutting edge part has a maximum height with respect to the lower surface at a first connection point where the first main cutting edge and the first auxiliary cutting edge meet, and
has a minimum height with respect to the lower surface at a second connection point where the first auxiliary cutting edge and the first sub-cutting edge meet.

3. The cutting insert according to claim 1 , wherein the straight line section forms a rake angle of 0.5 to 3 degrees with respect to the lower surface.

4. The cutting insert according to claim 1 , wherein, when viewing the upper surface, the first and second cutting edge parts are rotationally symmetrical by 90 degrees with respect to a center of the upper surface.

5. The cutting insert according to claim 1 , wherein a main cutting edge-neighboring clearance surface portion of the upper clearance surface, which contacts the first main cutting edge, has a constant width along a circumferential direction, when viewing the first lateral surface.

6. The cutting insert according to claim 1 , wherein a main cutting edge-neighboring clearance surface portion of the upper clearance surface, which contacts the main cutting edge, is shaped such that an angle between the main cutting edge-neighboring clearance surface portion and the lower surface increases with a decreasing distance to the first auxiliary cutting edge.

7. The cutting insert according to claim 1 , wherein the lower clearance surface has a constant width along a circumferential direction thereof, when viewing the first lateral surface, and
an angle formed by the lower clearance surface and the lower surface is constant along the circumferential direction thereof.

8. The cutting insert according to claim 1 , wherein the intermediate clearance surface forms an angle with respect to the lower surface which increases with a decreasing distance to the second lateral surface.

9. A cutting tool on which the cutting insert according to claim 1 is mounted, the cutting tool comprising a seat surface on which the lower surface is placed,
wherein the seat surface is formed such that the cutting insert is mounted at a negative radial rake angle and a positive axial rake angle.

10. A cutting insert comprising an upper surface and a lower surface facing opposite directions to each other, and first and second lateral surfaces connecting the upper surface and the lower surface and being adjacent to each other, wherein the cutting insert comprises:
a first cutting edge part forming a boundary between the upper surface and the first lateral surface;
a second cutting edge part forming a boundary between the upper surface and the second lateral surface; and
a corner cutting edge connecting the first cutting edge part and the second cutting edge part,
wherein the first cutting edge part comprises:
a first main cutting edge 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 connecting the first main cutting edge and the first sub-cutting edge so as to form a step therebetween,

wherein the first sub-cutting edge and the corner cutting edge, when viewing the first lateral surface, form one straight line and are inclined upward in a direction opposite to a direction toward the lower surface while gradually going in the direction toward the second cutting edge part,
wherein the second cutting edge part comprises a second main cutting edge forming one end at a portion contacting the corner cutting edge, and when the upper surface is an X-Y plane and a Z-axis passes through a center of the upper surface, viewing the first lateral surface after rotating the first lateral surface by 45 degrees with respect to the Z axis reveals that the first sub-cutting edge, the corner cutting edge, and the second main cutting edge form one straight line section and are inclined upward in a direction opposite to a direction toward the lower surface while gradually going in the direction toward the other end of the second main cutting edge.

Assignees

• Korloy Inc

Inventors

• Oh Min Seok
• Nam Ki Chan
• Lee Byeong Yun
• Kim Hyo San
• Kim Young Heum

Classifications

• B23C5/202 Primary

  Plate-like cutting inserts with special form (special form related to securing of the insert B23C5/22) · CPC title

• B23C2200/205

  Discontinuous cutting edges · CPC title

• B23C2210/045

  axial rake angle · CPC title

• B23C2200/0455

  Square · CPC title

• B23C2200/0461

  rounded · CPC title