Cutting Insert and Chip-Control Arrangement Therefor

• US 20130064613A1
• Filed: 04/20/2012
• Published: 03/14/2013
• Est. Priority Date: 09/13/2011
• Status: Active Grant

• Current Assignee: Iscar Limited (Berkshire Hathaway Incorporated)
• Original Assignee: Iscar Limited (Berkshire Hathaway Incorporated)
• Inventors: Krishtul, Roman
• Granted Patent: US 8,967,920 B2
• Time in Patent Office: Days
• US Class Current: 407/114
• CPC Class Codes: B23B 2200/0447 Parallelogram
• CPC Class Codes: B23B 2200/081 with projections chip breaking projections in general B23B2200/321
• CPC Class Codes: B23B 2200/082 with elevated clamping surface
• CPC Class Codes: B23B 2200/321 by chip breaking projections with projections on rake surface B23B2200/081
• CPC Class Codes: B23B 2260/104 Markings, i.e. symbols or other indicating marks
• CPC Class Codes: B23B 27/143 characterised by having chip-breakers
• CPC Class Codes: Y10T 407/23 including tool having plural alternatively usable cutting edges
• CPC Class Codes: Y10T 407/235 with integral chip breaker, guide or deflector
• CPC Class Codes: Y10T 407/24 with chip breaker, guide or deflector

Abstract

A cutting insert has at least first and second side surfaces, with a chip-control arrangement. The chip-control arrangement includes at least one projection disposed at an intersection of a corner of the cutting insert. When the chip-control arrangement includes two projections they can be disposed symmetrically on both sides of the intersection. Each of the at least one projections is elongated and extends longitudinally along an associated side surface.

Claims

1. A cutting insert (20), comprising

opposing top and bottom ends (22, 24) and at least first and second side surfaces (26A, 26B) extending therebetween,

a first insert corner (44A) comprising a corner cutting edge (54) formed at an intersection (56) of the first and second side surfaces (26A, 26B) and the top end (22), and

a chip-control arrangement (60) at the first insert corner (44A);

the chip-control arrangement (60) comprising

a first projection (28, 128) which is elongated and disposed on the top end (22) adjacent to the intersection (56) and which extends longitudinally along the first side surface (26A).

2. The cutting insert (20) according to claim 1, further comprising at the top end:

a land (58) extending along the intersection (56),

a chip evacuation surface (64), and

a chip deflecting surface (66) extending between the land (58) and chip evacuation surface (64); and

wherein at least a majority of the first projection (28) is located at the chip deflecting surface (66).

3. The cutting insert (20) according to claim 2, wherein the land (58) has a land width (W_L) which is variable.

4. The cutting insert (20) according to claim 3, wherein the land width (W_L) fulfills the condition 0.25 mm≦

W_L≦

0.36 mm.

5. The cutting insert (20) according to claim 2, wherein the land has a land maximum width (W_L2) which is located between the first projection (28) and the first side surface (26A).

6. The cutting insert (20) according to claim 1, wherein the first projection (28, 128) comprises first and second extremities (78, 80) and a middle portion (82) therebetween;

and

each of the first and second extremities (78, 80) is respectively closer to the first side surface (26A) than the middle portion (82).

7. The cutting insert (20) according to claim 2, wherein the first projection (28) is spaced-apart from the land (58).

8. The cutting insert (20) according to claim 2, wherein the first projection (28) is partly located on the chip evacuating surface (64).

9. The cutting insert (20) according to claim 2, wherein the land (58) decreases in height with increasing distance from the first side surface (26A) at a predetermined land angle α

, wherein 8°

≦

α

≦

12°

.

10. The cutting insert (20) according to claim 1, comprising a plurality of corners (44A, 44B, 44C, 44D), each of which comprises a chip-control arrangement (60) identical to said chip-control arrangement (60).

11. The cutting insert (20) according to claim 1, wherein the top and bottom ends (22, 24) are mirror-symmetrical.

12. The cutting insert (20) according to claim 1, wherein the corner cutting edge (54) has a radius of curvature (R) a

13. The cutting insert (20) according to claim 1, further comprising a central island (32) which comprises an elongated nose portion (34) directed towards the intersection (56).

14. The cutting insert (20) according to claim 1, wherein the first projection (28) has a length L_P, wherein 0.82 mm<

L_P<

1.42 mm.

15. The cutting insert (20) according to claim 1, wherein the first projection (28) has a width W_P, wherein 0.09 mm<

W_P<

0.49 mm.

16. The cutting insert (20) according to claim 2, wherein the first projection (28) comprises a projection peak (68), and

in relation to an upward direction D_U, a lowest point (86) of the land (58) is located higher than the projection peak (68).

17. The cutting insert (20) according to claim 16, wherein the projection peak (68) is spaced-apart from a cutting edge plane (P_CE) by a projection peak distance D_P, wherein 0.95 mm≦

D_P≦

1.05 mm.

18. The cutting insert (20) according to claim 1, wherein the chip-control arrangement (60) further comprises a second projection (30) which is elongated and disposed on the top end (22) adjacent to the intersection (56) and which extends longitudinally along the second side surface (26B).

19. The cutting insert (20) according to claim 18, wherein the first and second projections (28, 30) are disposed symmetrically about a corner bisector (B) at the intersection (56).

20. The cutting insert (20) according to claim 19, wherein the first and second projections (28, 30) are identical.

21. The cutting insert (20) according to claim 18, wherein the first and second projections (28, 30) are identical.

22. The cutting insert (20) according to claim 1, wherein the chip-control arrangement (60) comprises exactly and only two projections (28, 30).

23. The cutting insert (20) according to claim 1, wherein the chip-control arrangement (60) is associated with a single nose portion (34) of a central island (32).

24. The cutting insert (20) according to claim 1;

wherein

the first projection (128) comprises first and second extremities (78, 80) and a middle portion (82) therebetween;

each of the first and second extremities (78, 80) is respectively closer to the first side surface (26A) than the middle portion (82); and

the first and second extremities (78, 80) are generally perpendicular to the middle portion (82) and extend in a direction of the first side surface (26A) therefrom.

25. The cutting insert (20) according to claim 24, wherein the chip-control arrangement (60) comprises exactly and only two projections (128, 130).

26. The cutting insert (20) according to claim 1, wherein the first projection (28) is entirely located between ⅙

and 2/6 of a distance from the second side surface (26B) at the first corner (44A) to a midway point (P) of the first side surface (26A).

27. The cutting insert (20) according to claim 1, wherein the first projection (28) is entirely located within the first third of a distance from the second side surface (26B) at the first corner (44A) to a midway point (P) of the first side surface (26A).

28. The cutting insert (20) according to claim 27, wherein the chip-control arrangement (60) further comprises a second projection (30) which is elongated and disposed on the top end (22) adjacent to the intersection (56) and which extends longitudinally along the second side surface (26B).

29. The cutting insert (20) according to claim 28, wherein the first and second projections (28, 30) are disposed symmetrically about a corner bisector (B) at the intersection (56).

30. The cutting insert (20) according to claim 29, wherein the first and second projections (28, 30) are identical.

31. The cutting insert (20) according to claim 30, wherein the chip-control arrangement (60) at the first corner (44A) comprises exactly and only two projections (28, 30).

32. The cutting insert (20) according to claim 31, wherein the first projection (28) has a projection length L_P and a projection width W_P perpendicular to the projection length L_P and L_P≧

3 W_P.

33. The cutting insert (20) according to claim 1, wherein the first projection (28) has a projection length L_P and a projection width W_P perpendicular to the projection length L_P and L_P≧

3 W_P.