Cutting insert having a variable-width land and cutting tool

Patent metadata

Field	Value
Publication number	US-10010950-B2
Application number	US-201515129467-A
Country	US
Kind code	B2
Filing date	Mar 26, 2015
Priority date	Mar 27, 2014
Publication date	Jul 3, 2018
Grant date	Jul 3, 2018

Abstract

A cutting insert has an upper surface, a lower surface, a side surface connecting the upper and lower surfaces. An intersecting edge between the upper surface and the side surface is provided with a cutting edge. The cutting edge has, in order, a second major cutting edge, a first major cutting edge, a corner cutting edge connected to these major cutting edges, and a flat cutting edge. An obtuse interior first angle (θ) is formed by the second and first major cutting edges. A interior second angle (α) formed by the flat cutting edge and the first major cutting edge is larger than an interior third angle (β) formed by the flat cutting edge and the second major cutting edge. A land is provided adjacent to the first major cutting edge, a width of the land increasing toward the first corner cutting edge.

First claim

What is claimed is:

1. A cutting insert comprising an upper surface, a lower surface, and a side surface connecting the upper surface and the lower surface, wherein:
an intersecting edge between the upper surface and the side surface is partially or entirely provided with an upper cutting edge comprising a plurality of cutting edge portion groups;
in a plan view of the upper surface, each cutting edge portion group comprises a linear or curved first major cutting edge, a linear or curved second major cutting edge connected to the first major cutting edge, a substantially arc-like corner cutting edge connected to the first major cutting edge on an opposite side of the second major cutting edge, and a linear or curved flat cutting edge connected to the corner cutting edge on an opposite side of the first major cutting edge;
an interior first angle (θ) formed by the linear second major cutting edge or a chord formed by connecting both ends of the curved second major cutting edge, and the linear first major cutting edge or a chord formed by connecting both ends of the curved first major cutting edge, is an obtuse angle;
an interior second angle (α) formed by the flat cutting edge and the linear first major cutting edge or the chord of the curved first major cutting edge is larger than an interior third angle (β) formed by the flat cutting edge and the linear second major cutting edge or the chord of the curved second major cutting edge;
a land is provided adjacent to the first major cutting edge on the upper surface; and
a width of the land provided adjacent the first major cutting edge increases toward the corner cutting edge.

2. The cutting insert according to claim 1 , wherein:
the land is also provided adjacent to the second major cutting edge on the upper surface,
a width of the land provided adjacent to the second major cutting edge also increases toward the corner cutting edge, and
a rate of increase of the width of the land adjacent to the first major cutting edge is larger than a rate of increase of the width of the land adjacent to the second major cutting edge.

3. The cutting insert according to claim 2 , wherein:
the rate of increase of the width of the land adjacent to the first major cutting edge is two to five times larger than the rate of increase of the width of the land adjacent to the second major cutting edge.

4. The cutting insert according to claim 1 , wherein, in a side view of the insert:
the second major cutting edge and the first major cutting edge are inclined with respect to the lower surface; and
a direction of inclination is set such that the second major cutting edge and the first major cutting edge approach the lower surface as distances from the corner cutting edge increase.

5. The cutting insert according to claim 1 , wherein:
an intersecting edge between the lower surface and the side surface is partially or entirely provided with a lower cutting edge;
the lower cutting edge also comprises a plurality of cutting edge portion groups;
the lower cutting edge has the same shape as the upper cutting edge formed on the intersecting edge between the upper surface and the side surface.

6. The cutting insert according to claim 1 , wherein:
the side surface is provided with a first inclined surface arranged on an upper surface side and a second inclined surface arranged on a lower surface side with respect to the first inclined surface,
the first inclined surface being inclined such that a portion closer to the lower surface is located closer to a center of the cutting insert,
the second inclined surface being inclined such that a portion closer to the upper surface is located closer to the center of the cutting insert.

7. A tool body on which the cutting insert according to claim 6 is mounted, wherein:
the tool body comprises an insert mounting seat for mounting the cutting insert;
the insert mounting seat comprises a first side wall; and
the first side wall comprises a projected part that is brought into contact with the second inclined surface formed in the side surface of the cutting insert.

8. The tool body according to claim 7 , wherein:
an outer shape of the tool body is cylindrical;
the insert mounting seat further comprises a second side wall that is located on an outer circumferential side of the body with respect to the first sidewall; and
the second side wall comprises a projected part that is brought into contact with the first inclined surface formed in the side surface of the cutting insert.

9. A cutting insert comprising an upper surface, a lower surface, and a side surface connecting the upper surface and the lower surface, wherein:
an intersecting edge between the upper surface and the side surface is provided with an upper cutting edge comprising a plurality of cutting edge portion groups;
in a plan view of the upper surface, each cutting edge portion group comprises a first major cutting edge, a second major cutting edge connected to the first major cutting edge, a substantially arc-like corner cutting edge connected to the first major cutting edge on an opposite side of the second major cutting edge, and a flat cutting edge connected to the corner cutting edge on an opposite side of the first major cutting edge;
an interior first angle (θ) formed between the second major cutting edge and the first major cutting edge is an obtuse angle;
an interior second angle (α) formed by the flat cutting edge and the first major cutting edge is larger than an interior third angle (β) formed by the flat cutting edge and the second major cutting edge;
a land is provided adjacent to the first major cutting edge on the upper surface; and
a width of the land provided adjacent the first major cutting edge increases toward the corner cutting edge.

10. The cutting insert according to claim 9 , wherein:
the land is also provided adjacent to the second major cutting edge;
a width of the land provided adjacent to the second major cutting edge also increases toward the corner cutting edge; and
a rate of increase of the width of the land adjacent to the first major cutting edge is larger than a rate of increase of the width of the land adjacent to the second major cutting edge.

11. The cutting insert according to claim 10 , wherein:
the rate of increase of the width of the land adjacent to the first major cutting edge is two to five times larger than the rate of increase of the width of the land adjacent to the second major cutting edge.

12. The cutting insert according to claim 10 , wherein, in a side view of the insert:
the second major cutting edge and the first major cutting edge are inclined with respect to the lower surface; and
a direction of inclination is set such that the second major cutting edge and the first major cutting edge approach the lower surface as distances from the corner cutting edge increase.

13. The cutting insert according to claim 10 , wherein:
an intersecting edge between the lower surface and the side surface is provided with a lower cutting edge;
the lower cutting edge also comprises a plurality of cutting edge portion groups; and
the lower cutting edge has the same shape as the upper cutting edge formed on the intersecting edge between the upper surface and the side surface.

14. The cutting insert ( 1 ) according to claim 10 , wherein:
the side surface is provided with a first inclined surface arranged on an upper surface side and a second inclined surface arranged on a lower surface side with respect to the first inclined surface,
the first inclined surface being inclined such that a portion closer to the lower surface is locat

Assignees

• Tungaloy Corp

Inventors

• Matsumura Takahiro
• Yoshida Satoru

Classifications

• B23C5/202

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

• B23C2200/128

  with one or more grooves · CPC title

• B23C2210/045

  axial rake angle · CPC title

• B23C2200/201

  Details of the nose radius and immediately surrounding areas · CPC title

• B23C2200/366

  Variable · CPC title