Cutting insert and cutting tool

Patent metadata

Field	Value
Publication number	US-11745276-B2
Application number	US-202217589352-A
Country	US
Kind code	B2
Filing date	Jan 31, 2022
Priority date	Feb 18, 2021
Publication date	Sep 5, 2023
Grant date	Sep 5, 2023

Abstract

Provided is a cutting insert configured to be able to realize downsizing of a cutting tool. A cutting insert includes: an upper surface and a lower surface facing each other and having a plurality of corner parts; a side surface connecting the upper surface and the lower surface and forming intersecting edges with the upper surface and the lower surface, respectively; and a through hole that has a central axis extending from the upper surface to the lower surface and that is formed for penetration from the upper surface to the lower surface. A corner cutting edge arranged at a position corresponding to a corner part of the upper surface, a minor cutting edge connected to a first end of the corner cutting edge, and a major cutting edge connected to a second end of the corner cutting edge are formed on the intersecting edge between the upper surface and the side surface. A flank of the corner cutting edge and a recessed part located on the lower surface side of the flank of the corner cutting edge are formed on the side surface.

First claim

What is claimed is:

1. A cutting insert, comprising:
an upper surface and a lower surface away from each other and having a plurality of corner parts;
a side surface connecting the upper surface and the lower surface and forming intersecting edges with the upper surface and the lower surface, respectively; and
a through hole that has a central axis extending from the upper surface to the lower surface and that is formed for penetration from the upper surface to the lower surface, wherein
a corner cutting edge arranged at a position corresponding to a corner part of the upper surface, a minor cutting edge connected to a first end of the corner cutting edge, and a major cutting edge connected to a second end of the corner cutting edge are formed on the intersecting edge between the upper surface and the side surface,
a flank of the corner cutting edge and a recessed part are formed on the side surface, the recessed part being located between the lower surface and the flank of the corner cutting edge,
an outer rim of the recessed part includes a lower rim intersecting edge between the lower surface and the side surface,
the lower rim intersecting edge of the recessed part recedes toward the central axis of the through hole from a first extended projection line obtained by stretching the flank of the corner cutting edge toward the lower surface along the flank of the corner cutting edge and projecting the flank of the corner cutting edge on the same plane as the lower surface,
a flank of the major cutting edge is formed on the side surface,
a first intersecting edge that is between the side surface and the lower surface and that is located between the lower surface and the major cutting edge recedes toward the central axis of the through hole from a second extended projection line obtained by stretching the flank of the major cutting edge toward the lower surface along the flank of the major cutting edge and projecting the flank of the major cutting edge on the same plane as the lower surface, and
a maximum receding quantity of the lower rim intersecting edge of the recessed part from the first extended projection line is greater than a maximum receding quantity of the first intersecting edge from the second extended projection line.

2. The cutting insert according to claim 1 , wherein
a flank of the minor cutting edge is formed on the side surface, and
the recessed part is formed so as to extend to a position between the lower surface and the flank of the minor cutting edge.

3. The cutting insert according to claim 1 , wherein, in a bottom view, a first internal angle that is formed by a virtual extension line obtained by stretching the lower rim intersecting edge of the recessed part toward the major cutting edge and a virtual line on the major cutting edge is greater than a second internal angle that is formed by a virtual extension line obtained stretching the minor cutting edge toward the corner cutting edge and a virtual extension line obtained by stretching the major cutting edge toward the corner cutting edge.

4. The cutting insert according to claim 1 , wherein, in the bottom view, a first end and a second end of the lower rim intersecting edge of the recessed part are positioned so as to oppose each other with a virtual line therebetween, the virtual line passing through a peak of the corner cutting edge and the central axis of the through hole.

5. The cutting insert according to claim 1 , wherein the outer rim of the recessed part includes a top rim part formed at a lower end of the flank of the corner cutting edge, a first lateral rim part connected from the top rim part to the first end of the lower rim intersecting edge, and a second lateral rim part connected from the top rim part to the second end of the lower rim intersecting edge.

6. The cutting insert according to claim 1 , wherein the recessed part has a curved shape that is recessed toward the central axis of the through hole.

7. The cutting insert according to claim 1 , wherein
the cutting insert is configured to be fixed to a tool body of a cutting tool, and
when viewed in a direction of the central axis of the through hole, a size twice a maximum length of the cutting insert is greater than a tool diameter of the tool body of the cutting tool to which the cutting insert is fixed.

8. A cutting tool, comprising:
the cutting insert described in claim 1 ; and
a tool body to which the cutting insert is fixed.

9. A cutting insert, comprising:
an upper surface and a lower surface facing each other and having a plurality of corner parts;
a side surface connecting the upper surface and the lower surface and forming intersecting edges with the upper surface and the lower surface, respectively; and
a through hole that has a central axis extending from the upper surface to the lower surface and that is formed for penetration from the upper surface to the lower surface, wherein
a corner cutting edge arranged at a position corresponding to a corner part of the upper surface, a minor cutting edge connected to a first end of the corner cutting edge, and a major cutting edge connected to a second end of the corner cutting edge are formed on the intersecting edge between the upper surface and the side surface,
a flank of the corner cutting edge and a recessed part are formed on the side surface, the recessed part being located between the lower surface and the flank of the corner cutting edge,
an outer rim of the recessed part includes a lower rim intersecting edge between the lower surface and the side surface,
the lower rim intersecting edge of the recessed part recedes toward the central axis of the through hole from a first extended projection line obtained by stretching the flank of the corner cutting edge toward the lower surface along the flank of the corner cutting edge and projecting the flank of the corner cutting edge on the same plane as the lower surface,
in a bottom view, a first internal angle that is formed by a virtual extension line obtained by stretching the lower rim intersecting edge of the recessed part toward the major cutting edge and a virtual line on the major cutting edge is greater than a second internal angle that is formed by a virtual extension line obtained stretching the minor cutting edge toward the corner cutting edge and a virtual extension line obtained by stretching the major cutting edge toward the corner cutting edge.

10. The cutting tool according to claim 8 , wherein, when viewed in a direction of the central axis of the through hole, a size twice a maximum length of the cutting insert is greater than a tool diameter of the tool body of the cutting tool to which the cutting insert is fixed.

Assignees

• Tungaloy Corp

Inventors

• Aso Takahiro

Classifications

• B23C5/2213 Primary

  having a special shape · CPC title

• B23C5/20

  with removable cutter bits or teeth {or cutting inserts} · CPC title

• B23C2200/0477

  Triangular · CPC title

• B23C2200/12

  Side or flank surfaces · CPC title

• B23C2200/125

  discontinuous · CPC title