Cutting insert and shoulder milling tool

Patent metadata

Field	Value
Publication number	US-11229960-B2
Application number	US-201716472713-A
Country	US
Kind code	B2
Filing date	Nov 10, 2017
Priority date	Dec 22, 2016
Publication date	Jan 25, 2022
Grant date	Jan 25, 2022

Abstract

A cutting insert and a shoulder milling tool are disclosed. The cutting insert includes a surface-wiping secondary cutting edge inclined in relation to a median plane of the cutting insert, such that a distance to the median plane decreases in a direction toward a corner cutting edge. A circumferential surface includes a clearance surface extending along a main cutting edge. The clearance surface along the main cutting edge extends at an acute angle to the median plane, such that the clearance surface forms a negative nominal clearance angle, and wherein the circumferential surface includes first and second abutment surfaces configured for abutment against axial and/or radial support surfaces of the milling tool, the abutment surfaces extending along at least part of the main cutting edge and the surface-wiping secondary cutting edge.

First claim

The invention claimed is:

1. A cutting insert for a shoulder milling tool, the cutting insert comprising:
a body having a trigonal shape and a median plane extending through the body;
a first surface, an opposite second surface, and a circumferential surface extending between the first surface and the second surface, the first and second surfaces extending on opposite sides of the median plane;
three indexable cutting edges extending along an intersection between the first surface and the circumferential surface, wherein each indexable cutting edge, as seen in a view towards the first surface, extends along a corner of the trigonally shaped body, wherein each indexable cutting edge includes a main cutting edge, a corner cutting edge, and a surface-wiping secondary cutting edge, wherein the main cutting edge adjoins the corner cutting edge, and the corner cutting edge adjoins the surface-wiping secondary cutting edge, wherein the surface-wiping secondary cutting edge is inclined in relation to the median plane such that a distance to the median plane decreases in a direction towards the corner cutting edge, wherein the circumferential surface includes a clearance surface extending along the main cutting edge, wherein the clearance surface along the main cutting edge extends at an acute angle to the median plane, such that the clearance surface forms a negative nominal clearance angle, wherein the circumferential surface includes a first abutment surface configured for abutment against an axial and/or radial support surface of the shoulder milling tool, the first abutment surface extending along at least part of the main cutting edge, and wherein the circumferential surface includes a second abutment surface configured for abutment against the axial and/or radial support surface of the shoulder milling tool, the second abutment surface extending along at least a part of the surface-wiping secondary edge, wherein the first surface includes a flat centre surface transforming into an inclined main rake face adjacent to the main cutting edge, wherein an entirety of the main cutting edge and the inclined main rake face extends at a greater distance from the median plane than the flat centre surface.

2. The cutting insert according to claim 1 , wherein the circumferential surface includes a circumferential countersunk waist portion situated at the median plane, wherein the first and second abutment surfaces are formed in the circumferential countersunk waist portion.

3. The cutting insert according to claim 1 , wherein the surface-wiping secondary cutting edge extends at an average angle within a range of 1-6 degrees to the median plane.

4. The cutting insert according to claim 1 , wherein the flat centre surface transforms into an inclined secondary rake face adjacent to the surface-wiping secondary cutting edge, wherein an entirety of the surface-wiping secondary cutting edge and the inclined secondary rake face are arranged at a greater distance from the median plane than the flat centre surface.

5. The cutting insert according to claim 1 , wherein the cutting insert is a double-sided cutting insert with three additional indexable cutting edges extending along an intersection between the second surface and the circumferential surface, each of the first and second surfaces having a flat centre surface arranged to abut against a bottom support surface of the shoulder milling tool.

6. The cutting insert according to claim 1 , wherein the main cutting edge is inclined in relation to the median plane such that a distance to the median plane decreases in a direction away from the corner cutting edge.

7. The cutting insert according to claim 6 , wherein the main cutting edge extends at an average angle within a range of 6-14 degrees to the median plane.

8. The cutting insert according to claim 1 , wherein the clearance surface along the main cutting edge extends at an acute angle within a range of 83-87 degrees to the median plane.

9. A shoulder milling tool comprising:
a tool body provided with an insert seat; and
a cutting insert according to claim 1 arranged in the insert seat.

10. The shoulder milling tool according to claim 9 , wherein the insert seat is provided with a bottom support surface, a first side support surface, a second side support surface, and a third side support surface, wherein the insert seat has a radial opening for exposing the main cutting edge of the cutting insert and an axial opening for exposing the surface-wiping secondary cutting edge of the cutting insert, wherein the first side support surface, the second side support surface, and the third side support surface extend transverse to the bottom support surface, wherein the first and second side support surfaces are arranged to support the first and second abutment surfaces of an inactive indexable cutting edge at a first end of the insert seat opposite to the axial opening, and the third side support surface is arranged to support the second abutment surface of another inactive indexable cutting edge at a second end of the insert seat close to the axial opening, and wherein the cutting insert is arranged with the second surface abutting against the bottom support surface.

11. The shoulder milling tool according to claim 9 , wherein the insert seat is configured to provide a negative axial rake angle for the median plane of the cutting insert arranged in the insert seat, and wherein the negative axial rake angle is within a range of 1-11 degrees.

12. The shoulder milling tool according to claim 9 , wherein the insert seat is configured to provide a negative radial rake angle for the median plane of the cutting insert arranged in the insert seat, and wherein the negative radial rake angle is within a range of 8-20 degrees.

Assignees

• Sandvik Intellectual Property

Inventors

• Eriksson Thomas
• Jansson Udd Jorgen

Classifications

• B23C5/202 Primary

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

• B23C2200/293

  Variable clearance angles · CPC title

• B23C5/2213

  having a special shape · CPC title

• B23C5/06 Primary

  Face-milling cutters, i.e. having only or primarily a substantially flat cutting surface · CPC title

• B23C2200/284

  Negative clearance angles · CPC title