Cutting insert, cutting tool, and method of manufacturing machined product using the same

• US 10,442,006 B2
• Filed: 06/20/2016
• Issued: 10/15/2019
• Est. Priority Date: 06/23/2015
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: Inoue, Yoshihiro
• Primary Examiner(s): Fridie, Jr., Willmon
• Application Number:
  US15/738,149
• Publication Number:
  US 20180169767A1
• Time in Patent Office: 1,212 Days
• CPC Class Codes: B23B 2200/049 Triangular
• CPC Class Codes: B23B 27/02 Cutting tools with straight main part and cutting edge at an angle B23B27/04 - B23B27/08 take precedence
• CPC Class Codes: B23B 27/065 Thread-turning tools
• CPC Class Codes: B23B 27/143 characterised by having chip-breakers
• CPC Class Codes: B23B 27/1611 characterised by having a special shape
• CPC Class Codes: B23B 27/1681 Adjustable position of the plate-like cutting inserts
• CPC Class Codes: B23B 27/1688 Height of the cutting tip adjustable
• CPC Class Codes: B23B 27/22 Cutting tools with chip-breaking equipment B23B27/045, B23B27/143, B23B27/16 take precedence; arrangements for chip-breaking B23B25/02; for milling tools B23C5/165
• CPC Class Codes: B23C 2200/0477 Triangular

Abstract

According to the present disclosure, a cutting insert includes an upper surface having a polygonal shape and includes a corner, a side surface adjacent to the upper surface, a cutting edge and a protrusion. The cutting edge is located at a ridge part in which the upper surface intersects with the side surface and includes a corner part located at the corner. The protrusion is located on the upper surface. The protrusion includes a first protrusion on a bisector of the corner in a top view. The protrusion further includes a second protrusion adjacent to the first protrusion in a direction orthogonal to the bisector. The second protrusion is closer to the corner than the first protrusion in the top view.

Claims

1. A cutting insert, comprising:

an upper surface having a polygonal shape and comprising a corner;

a side surface adjacent to the upper surface;

a cutting edge located at a ridge part in which the upper surface intersects with the side surface and comprising a corner part located at the corner; and

a protrusion located on the upper surface, comprising;

a first protrusion located on a bisector of the corner in a top view;

a second protrusion adjacent to the first protrusion in a direction orthogonal to the bisector in the top view; and

a third protrusion; and

wherein

the second protrusion is closer to the corner than the first protrusion in the top view;

the first protrusion is located between the second protrusion and the third protrusion in the direction orthogonal to the bisector in the top view, and

the first protrusion is closer to the corner than the third protrusion in the top view.

2. The cutting insert according to claim 1, wherein

the second protrusion is taller than the first protrusion.

3. The cutting insert according to claim 1, wherein

each of the second protrusion and the third protrusion are taller than the first protrusion.

4. The cutting insert according to claim 1, wherein

the upper surface comprises a recess located along the cutting edge, and

a tip of the first protrusion, a tip of the second protrusion, and a tip of the third protrusion are located at the recess.

5. The cutting insert according to claim 4, wherein

the first protrusion is positioned lower than the cutting edge.

6. The cutting insert according to claim 1, wherein

each of the second protrusion and the third protrusion extends toward more inside the upper surface than the first protrusion in the top view.

7. The cutting insert according to claim 1, wherein

the upper surface further comprises a first surface and a second surface which are located more inside than the protrusion and which are inclined upward as going away from the corner,

the first surface and the second surface are located sequentially from a side close to the second protrusion in the direction orthogonal to the bisector in the top view,

an upper edge of the second surface is inclined and getting away from the corner as going from a second protrusion side toward a third protrusion side in the direction orthogonal to the bisector in the top view, and

an angle θ

1 formed by the upper edge of the second surface and a straight line X orthogonal to the bisector is larger than an angle θ

2 formed by the straight line X and an imaginary straight line connecting a top of the second protrusion and a top of the third protrusion in the top view.

8. The cutting insert according to claim 7, wherein

a distance in a direction parallel to the bisector between the top of the third protrusion and the upper edge of the second surface is larger than a distance in a direction parallel to the bisector between the top of the second protrusion and the upper edge of the second surface.

9. The cutting insert according to claim 8, wherein

each of the first protrusion, the second protrusion, and the third protrusion is positioned lower than the upper edge of the second surface.

10. The cutting insert according to claim 7, wherein

an upper edge of the first surface is inclined and getting away from the corner as going from the second protrusion side toward the third protrusion side in the direction orthogonal to the bisector in the top view, and

an angle θ

3 formed by the upper edge of the first surface and the straight line X is equal to the angle θ

2 in the top view.

11. The cutting insert according to claim 10, wherein

each of the first protrusion, the second protrusion, and the third protrusion is positioned lower than the upper edge of the first surface.

12. The cutting insert according to claim 7, wherein

an inclination angle θ

4 of the second surface decreases and an inclination angle θ

5 of the first surface is constant as going from the second protrusion side toward the third protrusion side in the direction orthogonal to the bisector.

13. A cutting tool, comprising:

a holder comprising an insert pocket; and

a cutting insert according to claim 1, the cutting insert being attached to the insert pocket with the cutting edge protruding outward beyond the holder.

14. A method of manufacturing a machined product, comprising:

rotating a workpiece;

bringing the cutting edge in a cutting tool according to claim 13 into contact with the workpiece being rotated; and

separating the cutting tool from the workpiece.

15. A cutting insert, comprising:

an upper surface having a polygonal shape and comprising a corner;

a side surface adjacent to the upper surface;

a cutting edge located at a ridge part in which the upper surface intersects with the side surface and comprising a corner part located at the corner; and

a protrusion located on the upper surface, comprising;

a first protrusion located on a bisector of the corner in a top view; and

a second protrusion adjacent to the first protrusion in a direction orthogonal to the bisector in the top view, and

wherein

the second protrusion is closer to the corner than the first protrusion in the top view, and

the second protrusion is taller than the first protrusion.

16. The cutting insert according to claim 15, wherein

the protrusion further comprises a third protrusion,

the first protrusion is located between the second protrusion and the third protrusion in the direction orthogonal to the bisector in the top view, and

the first protrusion is closer to the corner than the third protrusion in the top view.

17. The cutting insert according to claim 16, wherein

each of the second protrusion and the third protrusion are taller than the first protrusion.

18. A cutting tool, comprising:

a holder comprising an insert pocket; and

a cutting insert according to claim 15, the cutting insert being attached to the insert pocket with the cutting edge protruding outward beyond the holder.

19. A method of manufacturing a machined product, comprising:

rotating a workpiece;

bringing the cutting edge in a cutting tool according to claim 18 into contact with the workpiece being rotated; and

separating the cutting tool from the workpiece.