CUTTING ELEMENT

Abstract

A cutting element has a cutting head and a shaft. The cutting head is carried by the shaft and protrudes over the shaft transversely relative to a longitudinal extent of the shaft. The cutting head has a cutting edge, the cutting edge follows a circle segment with a circle center at a side of the shaft located in a virtual cutting head plane and is constructed symmetrically, when viewed in a direction perpendicular to the cutting head plane, with respect to a virtual cutting edge axis of symmetry which is contained in the cutting head plane. The cutting head has a chip guiding structure. The chip guiding structure is associated with the cutting edge, has a chip guiding groove and a plurality of chip guiding elements. Each chip guiding element has a longitudinal rib and a transverse rib.

Claims

1-15. (canceled)

16. A cutting element, comprising: a cutting head having a cutting edge; a shaft carrying said cutting head, said cutting head protruding over said shaft transversely relative to a longitudinal extent of said shaft; wherein said cutting edge follows a circle segment with a circle center at a side of said shaft, is disposed in a virtual cutting head plane and is constructed symmetrically, when viewed in a direction perpendicular to the virtual cutting head plane, with respect to a virtual cutting edge axis of symmetry which is contained in the virtual cutting head plane; and wherein said cutting head has a chip guiding structure, wherein said chip guiding structure is associated with said cutting edge, wherein said chip guiding structure has a chip guiding groove formed therein which is constructed to follow said cutting edge when viewed in the direction perpendicular to the virtual cutting head plane, said chip guiding structure further having a plurality of chip guiding elements which are constructed in a region of said chip guiding groove, wherein each of said chip guiding elements has a longitudinal rib and a transverse rib, wherein said longitudinal rib of each said of chip guiding elements has a rib ridge and rib flanks which decline from said rib ridge at both sides, wherein said rib ridge of each said longitudinal rib, when viewed in the direction perpendicular to the virtual cutting head plane, extends in each case substantially radially away from said cutting edge and is disposed between said transverse rib and said cutting edge, wherein in each of said chip guiding elements said transverse rib protrudes, when viewed in the direction perpendicular to the virtual cutting head plane, transversely relative to a longitudinal extent of said rib ridge over said rib ridge so that chips when rising from said chip guiding groove strike said transverse rib when the chips are guided by said longitudinal rib.

17. The cutting element according to claim 16, wherein said transverse rib in at least one of said chip guiding elements, in a rib longitudinal section which is orientated radially with respect to said cutting edge, when viewed in a direction perpendicular to the rib longitudinal section, is curved in a convex manner at a side of said rib ridge.

18. The cutting element according to claim 17, wherein said longitudinal rib, in said at least one chip guiding element in said rib longitudinal section which is orientated radially with respect to said cutting edge, when viewed in the direction perpendicular to the rib longitudinal section, is curved in a concave manner at a side of said cutting edge.

19. The cutting element according to claim 16, wherein at least one of said chip guiding elements is in a rib longitudinal section orientated radially with respect to said cutting edge, when viewed in a direction perpendicular to the rib longitudinal section, in a form of a capital letter S, wherein one curve of the capital letter S is formed in a region of said transverse rib so that said transverse rib is curved outwards, wherein another curve of the capital letter S is formed in a region of said rib ridge so that said rib ridge is curved inwards.

20. The cutting element according to claim 16, wherein in at least one of said chip guiding elements said transverse rib, when viewed in the direction perpendicular to the virtual cutting head plane, protrudes over said rib ridge at both sides transversely relative to the longitudinal extent of said rib ridge.

21. The cutting element according to claim 16, wherein in at least one of said chip guiding elements said transverse rib is, when viewed in the direction perpendicular to the virtual cutting head plane, in a form of a capital letter D, wherein a curve of the capital letter D faces said cutting edge when viewed in the direction perpendicular to the virtual cutting head plane.

22. The cutting element according to claim 16, wherein at least one of said chip guiding elements has a rib base, wherein said rib base carries said transverse rib with an edge being formed with said transverse rib, protrudes, when viewed in the direction perpendicular to the virtual cutting head plane, transversely with respect to the longitudinal extent of said rib ridge over said transverse rib with a base flank being formed at both sides and carries an end portion of said longitudinal rib.

23. The cutting element according to claim 16, wherein said chip guiding structure has a plurality of additional chip guiding elements, wherein said additional chip guiding elements are formed in a region of said chip guiding groove, wherein each of said additional chip guiding elements has an additional longitudinal rib with an additional rib ridge and additional rib flanks which decline from said additional rib ridge at both sides, wherein said additional rib ridge of each of said additional chip guiding elements, when viewed in the direction perpendicular to the virtual cutting head plane, extends in each case substantially radially away from said cutting edge, wherein each of said additional chip guiding elements, when viewed in the direction perpendicular to the virtual cutting head plane, has an end portion which is free from transverse ribs, wherein each said end portion is opposite said cutting edge when viewed in the direction perpendicular to the virtual cutting head plane, wherein said additional chip guiding elements and said chip guiding elements, when viewed in the direction perpendicular to the virtual cutting head plane, are disposed alternately in an alternating manner with respect to each other in a circumferential direction of said cutting edge.

24. The cutting element according to claim 23, wherein said additional longitudinal rib of one of said additional chip guiding elements is disposed, when viewed in the direction perpendicular to the virtual cutting head plane, substantially centrally on the virtual cutting edge axis of symmetry.

25. The cutting element according to claim 23, wherein, in at least one of said additional chip guiding element said additional longitudinal rib has a rib hump, wherein said rib hump, when viewed in the direction perpendicular to the virtual cutting head plane, is formed and disposed at said side of said cutting edge, wherein said rib hump protrudes from the virtual cutting head plane.

26. The cutting element according to claim 16, wherein said chip guiding structure has a plurality of recesses formed therein at said side of said cutting edge, wherein said recesses and said chip guiding elements are disposed alternately in an alternating manner when viewed in the direction perpendicular to the virtual cutting head plane.

27. The cutting element according to claim 16, wherein said chip guiding structure has a cutting edge chamfer, wherein said cutting edge chamfer, when viewed in the direction perpendicular to the virtual cutting head plane, has at least one V-shaped protuberance, wherein said V-shaped protuberance extends substantially radially away from said cutting edge, is planar and with an edge being formed is connected to said rib ridge of said longitudinal rib of at least one of said chip guiding elements, wherein said rib flanks of said longitudinal rib decline from said cutting edge chamfer laterally at both sides in a region of said V-shaped protuberance.

28. The cutting element according to claim 16, wherein said shaft has a V-shaped groove formed therein, wherein said V-shaped groove extends along the longitudinal extent of said shaft.

29. The cutting element according to claim 16, further comprising an additional cutting head, wherein said additional cutting head is carried by said shaft opposite said cutting head.

30. The cutting element according to claim 16, wherein said transverse rib of at least one of said chip guiding elements protrudes at least partially from the virtual cutting head plane.

Description

[0041] Other advantages and advantageous features of the invention will be appreciated with reference to the following description of an exemplary embodiment with reference to the appended Figures. In the drawings:

[0042] FIG. 1: shows an illustration of a cutting element in the region of a cutting head as a plan view;

[0043] FIG. 2: shows a detailed illustration of a region of the cutting element according to FIG. 1;

[0044] FIG. 3: shows an illustration of the cutting element according to FIG. 1 as a side view;

[0045] FIG. 4: shows a sectioned illustration of the cutting element according to FIG. 1 according to the lines of section A-A from FIG. 1;

[0046] FIG. 5: shows a sectioned illustration of the cutting element according to FIG. 1 according to the lines of section B-B from FIG. 1;

[0047] FIG. 6: shows a perspective illustration of the cutting element according to FIG. 1.

EMBODIMENT

[0048] One embodiment of a cutting element 1 is described with reference to FIGS. 1 to 6.

[0049] The cutting element 1 has a cutting head 2 and a shaft 3. The cutting head 2 is carried by the shaft 3 and protrudes transversely relative to the longitudinal extent of the shaft 3 over the shaft 3.

[0050] The cutting head 1 has a cutting edge 4. The cutting edge 4 follows a circle segment having a circle centre 5 at the side of the shaft 3. The cutting edge 4 is located in this instance in a virtual cutting head plane 6. The virtual cutting head plane 6 coincides in each case with the drawing plane of FIG. 1 and FIG. 2.

[0051] The cutting edge 4, when viewed in a direction perpendicular to the cutting head plane 6, that is, when viewed in a direction perpendicular to the drawing plane of FIG. 1 and FIG. 2, is constructed symmetrically with respect to a virtual cutting edge axis 7 of symmetry contained in the cutting head plane 6.

[0052] The cutting head 2 has a chip guiding structure 8. The chip guiding structure 8 is associated with the cutting edge 4 so that chips produced by the cutting edge 4 are guided away from the cutting edge 4 during feeding with chip breakage.

[0053] The chip guiding structure 8 has a chip guiding groove 9 which is constructed to follow the cutting edge 4 when viewed in a direction perpendicular to the cutting head plane 6 and a plurality of chip guiding elements 10 which are constructed in the region of the chip guiding groove 9; of the chip guiding elements 10, in FIG. 1 for reasons of clarity only one of the chip guiding elements 10 is designated 10.

[0054] Each chip guiding element 10 has a longitudinal rib 11 and a transverse rib 12. The longitudinal rib 11 of each chip guiding element 10 has a rib ridge 13 and rib flanks which decline from the rib ridge 13 at both sides, as shown in particular in FIG. 2.

[0055] The rib ridge 13 of each longitudinal rib 13 when viewed in a direction perpendicular to the cutting head plane 6 extends radially away from the cutting edge 4 in each case and is arranged between the transvers rib 12 and the cutting edge 4, as shown in particular in FIG. 2.

[0056] The transverse rib 12 in each chip guiding element 10, when viewed in a direction perpendicular to the cutting head plane 6, protrudes transversely relative to the longitudinal extent of the rib ridge 13 beyond the rib ridge 13 at both sides so that chips when rising from the chip guiding groove 9 strike the transverse rib 12 when the chips are guided from the longitudinal rib 11.

[0057] The cutting head 2 has a central portion 15. The chip guiding groove 9 extends, when viewed in a direction perpendicular to the cutting head plane 6, between the cutting edge 4 and the central portion 15. The chip guiding groove 9 declines at the side of the cutting edge 4 and rises at the side of the central portion 15 so that the chip guiding groove 9 bends the chips so as to follow the path of the chip guiding groove 9 in a radial direction with respect to the cutting edge 4, wherein the chips are additionally deformed at locations where the chips contact the chip guiding elements 10. The transverse ribs 12 increase the degree of deformation of the chips which has already been provided per se by the chip guiding groove 9 since the transverse ribs 12 are in each case formed and arranged at the side of the incline of the chip guiding groove 9. This leads to a shorter chip breakage and counteracts the formation of snarl chips.

[0058] In each chip guiding element 10, the transverse rib 12 is, when viewed in a direction perpendicular to the cutting head plane 6, in the form of the capital letter D, wherein the curve of the capital letter D faces the cutting edge 4 when viewed in a direction perpendicular to the cutting head plane 6.

[0059] Each chip guiding element 10 has a rib base 16, wherein the rib base 16 carries the transverse rib 12 with an edge being formed with the transverse rib 12, when viewed in a direction perpendicular to the cutting head plane 6, protrudes transversely with respect to the longitudinal extent of the rib ridge 13 beyond the transverse rib 12 with a base flank 17 formation at both sides and carries an end portion 18 of the longitudinal rib 11, as shown in particular in FIG. 2. The rib base 16 makes the incline in the region of the chip guiding groove 9 steeper, whereby the chips are deformed to an even greater extent.

[0060] The chip guiding elements 10 each have a longitudinal rib base 11a, wherein the longitudinal rib base 11a carries the longitudinal rib 11 with an edge being formed with the rib flanks 14, as shown in FIG. 2. The longitudinal rib bases 11a make the transition from the rib flanks 14 to the chip guiding groove 9 gentler.

[0061] The chip guiding structure 8 further has a plurality of additional chip guiding elements 19; of the additional chip guiding elements 19, in FIG. 1 for reasons of clarity, only one of the additional chip guiding elements 19 is designated 19.

[0062] FIG. 2 shows for the additional chip guiding elements 19 by way of example that the additional chip guiding elements 19 are formed in the region of the chip guiding groove 9, wherein each additional chip guiding element 19 has a longitudinal rib 20 having a rib ridge 21 and rib flanks 22 which decline at both sides from the rib ridge 21, wherein the rib ridge 21 of each additional chip guiding element 19, when viewed in a direction perpendicular to the cutting head plane 6, extends in each case radially away from the cutting edge 4, wherein each additional chip guiding element 19 has, when viewed in a direction perpendicular to the cutting head plane 6, an end portion 23 which is free from transverse ribs, wherein each end portion 23, when viewed in a direction perpendicular to the cutting head plane 6, is opposite the cutting edge 4.

[0063] FIG. 2 further shows for the additional chip guiding elements 19 by way of example that the additional chip guiding elements 19 each have a longitudinal rib base 20a, wherein the longitudinal rib base 20a carries the longitudinal rib 20 with an edge being formed with the rib flanks 22. The longitudinal rib bases 20a make the transition from the rib flanks 22 to the chip guiding groove 9 gentler.

[0064] The additional chip guiding elements 19 and the chip guiding elements 10 are, when viewed in a direction perpendicular to the cutting head plane 6, arranged alternately in an alternating manner with respect to each other in the circumferential direction of the cutting edge 4, as shown in particular in FIG. 1. The additional chip guiding elements 19 thus subdivide the region formed between two chip guiding elements 10 which are adjacent when viewed in a direction perpendicular to the cutting head plane 6 so that the chips can be supplied to the transverse ribs 12 with a chip blockage being avoided.

[0065] One of the longitudinal ribs 20 is located, when viewed in a direction perpendicular to the cutting head plane 6, centrally on the cutting edge axis 7 of symmetry, as shown in particular in FIG. 1. When feeding parallel with the cutting edge axis 7 of symmetry, the additional chip guiding element 19 with the longitudinal rib 20 which is arranged centrally in this manner ensures that the chips are supplied to the transverse ribs 12 which are arranged at both sides for this purpose.

[0066] In each of the additional chip guiding elements 19, the longitudinal rib 20 has a rib hump 24. The rib humps 24 are in each case arranged and formed, when viewed in a direction perpendicular to the cutting head plane 6, at the side of the cutting edge 4, wherein the rib humps 24 in each case protrude from the cutting head plane 6. The rib humps 24 prevent the chips from being able to run off directly via the rib ridges 21.

[0067] The chip guiding structure 8 further has a plurality of recesses 25 at the side of the cutting edge 4; of the recesses 25, in FIG. 1, for reasons of clarity, only two of the recesses 25 are designated 25. The recesses 25 are in each case formed in pairs of two recesses 25, which can also be referred to as a dual formation of the recesses 25.

[0068] The recesses 25, the chip guiding elements 20 and the additional chip guiding elements 19 are arranged alternately in an alternating manner when viewed in a direction perpendicular to the cutting head plane 6 so that in each case between a chip guiding element 10 and an additional chip guiding element 19 two recesses 25 are arranged and formed at the side of the cutting edge 4, as shown in particular in FIG. 1. The recesses 25 ensure a pre-deformation of the chips before the chips can slide into the chip guiding groove 9 and are guided at that location from the rib flanks 14 to the transverse ribs 12.

[0069] The chip guiding structure 8 further has a cutting edge chamfer 26. The cutting edge chamfer 26 has, when viewed in a direction perpendicular to the cutting head plane 6, a plurality of V-shaped protuberances 27, wherein the V-shaped protuberances 27 extend in each case radially away from the cutting edge 4, are planar and are connected to a rib ridge 13 in each case with an edge being formed. The rib flanks 14 consequently decline from the cutting edge chamfer 26 in each case laterally at both sides in the region of the V-shaped protuberances 27, which improves the chip deformation.

[0070] In FIG. 3, it can be clearly seen that the rib humps 24 protrude from the cutting head plane 6.

[0071] In FIG. 3, it can further be seen particularly clearly that the transverse ribs 12 protrude from the cutting head plane 6.

[0072] The cutting head 2 has a clearance face 28, wherein the clearance face 28 and the cutting edge chamfer 26 are connected to each other by the cutting edge 4. The clearance face 28 forms a protuberance 29 at the side of the additional cutting element 19, the longitudinal rib 20 of which is located centrally on the cutting edge axis 7 of symmetry.

[0073] When viewed in a direction perpendicular to the cutting head plane 6, two rib ridges 13 and rib ridges 21 which are adjacent to each other have a constant angle ?, wherein the angle ? is measured at the side of the cutting edge 4 and is in the range from 20? to 30?, preferably the angle ? is 25?; in FIG. 1, for reasons of clarity, only an angle ? is illustrated and the reference numerals of the rib ridges 13 and 21 are indicated in FIG. 2 by way of example for all the chip guiding elements 10 or all the additional chip guiding elements 19. The angle ? in the range from 20? to 30? ensures that the chips of the transverse rib 12 are better supplied. At an angle ? greater than 30?, the chips would escape laterally. At an angle ? less than 20?, the chips would run up against each other and thus block the region between the chip guiding elements 10 and the additional chip guiding elements 19 in each case.

[0074] The cross section which is shown in FIG. 4 and which is orientated radially with respect to the cutting edge 4 and can also be referred to as a rib longitudinal section shows for the additional chip guiding elements 19 by way of example that the longitudinal ribs 20 are in each case curved in a concave manner between the rib hump 24 and the central portion 15.

[0075] The cross section which is shown in FIG. 5 and which is orientated radially with respect to the cutting edge 4, and which can also be referred to as a rib longitudinal section, shows for the chip guiding elements 10 by way of example that the transverse rib 12 at the side of the rib ridge 13 is curved in a convex manner and that the longitudinal rib 11 at the side of the cutting edge 4 is curved in a concave manner so that chips which run on the rib ridge 13 are formed to follow the convex curvature and strike the transverse rib 12.

[0076] The chip guiding elements 10 are consequently in the radial rib longitudinal section thereof in the form of a capital letter S, wherein one curve of the capital letter S is formed in the region of the transverse rib 12 so that the transverse rib 12 bends outwards, wherein the other curve of the capital letter S is formed in the region of the rib ridge 13 so that the rib ridge 13 bends inwards.

[0077] FIG. 6 shows a perspective illustration of the cutting element 1, according to which it can be seen that the cutting element 1 has an additional cutting head 200 which is constructed in a similar manner to the cutting head 2. The additional cutting head 200 is carried by the shaft 3 opposite the cutting head 1 so that, after a rotation of the shaft 3 which brings the cutting head 200 into the position of the cutting head 2, a feed operation can be continued.

[0078] The shaft 3 has a V-shaped groove 30 by means of which the cutting element 1 can be clamped in a holder in a positive-locking manner. The V-shaped groove 30 consequently extends along the longitudinal extent of the shaft 3.

[0079] The V-shaped groove 30 has in the groove base thereof a U-shaped groove 31 The U-shaped groove 31 and the V-shaped groove 30 extend into the central portion 15, wherein the U-shaped groove 31 ensures a coolant supply of the cutting edge 4.

[0080] The present invention is not limited to the embodiment of the cutting element 1 as shown in FIGS. 1 to 6. It is also conceivable and possible for the cutting element 1 to be produced without the additional cutting elements 19 and/or without the recesses 25.

[0081] It is further conceivable and also possible for only one of the chip guiding elements 10 to have the transverse rib 12 or preferably only two of the chip guiding elements 10 to have the transverse rib 12 in each case.