Indexable cutting insert

Abstract

The present invention relates to an indexable cutting insert (4) for mounting in an insert seat (3) of a tool body (2) of a shoulder milling tool (1), wherein the cutting insert (4) is generally defined by a triangular top surface (5), a triangular bottom surface (6), and three peripheral surfaces (7) extending between the top surface (5) and the bottom surface (6), and on each side of the cutting insert (4), a respective one of the three peripheral surfaces extends along an edge of the triangular top surface (5) and along an edge of the triangular bottom surface (6), and the cutting insert (4) has three cutting corners ( The present invention relates to an indexable cutting insert (4) having a cutting corner (8), three major cutting edges (9), and three minor cutting edges (10), each of the cutting corners (8) connecting the major cutting edges (9) and the minor cutting edges (10), each of the cutting corners (8), each of the major cutting edges (9), and each of the minor cutting edges (10) being located at an intersection of the top surface (5) or the bottom surface (6) with one of the peripheral surfaces (7), each of the peripheral surfaces (7) having a flat contact surface (15), the flat contact surface being defined by the major cutting edge (9) of the top surface (5) and the major cutting edge (9) of the bottom surface (6).

Description

[Technical field]

[0001] The present invention relates to an indexable cutting insert for mounting in an insert seat of a tool body of a shoulder milling tool, the cutting insert being generally defined by a triangular top surface, a triangular bottom surface, and three peripheral surfaces extending between the top and bottom surfaces, with each side of the cutting insert having a respective one of the three peripheral surfaces extending along an edge of the triangular top surface and along an edge of the triangular bottom surface, the cutting insert comprising three cutting corners, three major cutting edges, and three minor cutting edges on each of the top and bottom surfaces, each of the cutting corners connecting the major and minor cutting edges, each of the cutting corners, each of the major cutting edges, and each of the minor cutting edges being located at an intersection of the top or bottom surface with one of the peripheral surfaces. [Background technology]

[0002] Many machine parts have designs that require machining of a metal workpiece to form a shoulder that is disposed at an angle relative to a wall surface. In so-called shoulder milling, various types of indexable cutting inserts are known, for example triangular double-sided cutting inserts of the type described above. A problem with some such known cutting inserts is that it can be difficult to manufacture machine parts that meet close tolerances. Summary of the Invention

[0003] It is an object of the present invention to provide an indexable cutting insert which alleviates the above-mentioned problems and improves the ability to manufacture machine parts meeting tight tolerances.

[0004] The above object is achieved by the invention as set forth in claim 1.

[0005] According to a first aspect of the present invention, at least one of the above objects is addressed by an indexable cutting insert for mounting in an insert seat of a tool body of a shoulder milling tool, the cutting insert being generally defined by a triangular top surface, a triangular bottom surface and three peripheral surfaces extending between the top and bottom surfaces, with each side of the cutting insert having a respective one of the three peripheral surfaces extending along an edge of the triangular top surface and along an edge of the triangular bottom surface, the cutting insert comprising three cutting corners, three major cutting edges and three minor cutting edges on each of the top and bottom surfaces, each of the cutting corners connecting the major and minor cutting edges, each of the cutting corners, each of the major cutting edges and each of the minor cutting edges being provided at an intersection of the top or bottom surface with one of the peripheral surfaces, each of the peripheral surfaces comprising a flat contact surface, the flat contact surface being defined by the major cutting edge on the top surface and the major cutting edge on the bottom surface.

[0006] The present invention provides a triangular indexable cutting insert, the indexable cutting insert has six sets of cutting edges. After indexing and reversing the cutting insert, the six sets of cutting edges can be used in turn, and the overall tool life is six times that of a cutting insert with one set of cutting edges. Each set of cutting edges includes a primary cutting edge for milling a wall surface, a secondary cutting edge for milling a bottom surface, and a cutting corner for milling a corner between the wall surface and the bottom surface of the workpiece to provide a shoulder on the workpiece. The cutting corner connects the primary cutting edge and the secondary cutting edge.

[0007] Thanks to the inventive flat contact surfaces on each side of the cutting insert, defined by the top and bottom major cutting edges respectively, the indexable cutting insert can be held securely in the insert seat and a stable connection between the cutting insert and the cutting tool body can be provided. Another advantage is the improved precision of the mounting position of the cutting insert in the insert seat. Thus, the cutting insert is less susceptible to vibration and due to the precise positioning, machine parts can be manufactured to tighter tolerances.

[0008] Advantageously, the contact surface of the present invention does not interfere with other design aspects of the cutting insert, so that the cutting insert of the present invention further provides improved positional accuracy and stability.

[0009] The intersection of each of the side surfaces with the top surface provides a single major cutting edge, a single minor cutting edge, and two cutting corners. Similarly, the intersection of each of the side surfaces with the bottom surface provides a single major cutting edge, a single minor cutting edge, and two cutting corners.

[0010] In one embodiment of the present invention, the top surface portion and the bottom surface portion are substantially parallel. Additionally, the cutting insert includes a mid-plane located intermediate the top surface and the bottom surface. The mid-plane extends parallel to the mutually parallel top and bottom surface portions.

[0011] In one embodiment, each of the contact surfaces is perpendicular to the mid-plane. Thus, in this embodiment, the cutting insert is a negative cutting insert with respect to the major cutting edge.

[0012] In one embodiment, each of the minor cutting edges is straight.

[0013] In one embodiment of the present invention, the cutting insert comprises a mid-plane located intermediate the top and bottom surfaces, the cutting insert comprises three transition edges on each of the top and bottom surfaces, the transition edges are located at intersections of the top or bottom surfaces with one of the peripheral surfaces, each of the transition edges connects a major cutting edge and a minor cutting edge, when the major cutting edges and the transition edges extend on the mid-plane, each of the transition edges forms an angle with the major cutting edge to which it is connected, when extended on the mid-plane, each of the major cutting edges is straight and has an overall length, the overall length being between the cutting corner to which the major cutting edge is connected and the transition edge to which the major cutting edge is connected, each of the contact surfaces extends along at least 2 / 3 of the overall length of the major cutting edges, and the major cutting edges define respective contact surfaces of the top and bottom surfaces.

[0014] In one embodiment, each of the contact surfaces extends along at least 2 / 3 of the length of the major cutting edge, the major cutting edges defining the respective contact surfaces. In one embodiment, each of the contact surfaces extends along the entire length of the major cutting edge. Increasing the distance that the contact surfaces extend along the major cutting edge increases the area of ​​the flat contact surface.

[0015] In one embodiment of the invention, each of the flat contact surfaces extends from a cutting corner connecting the major cutting edge on the top surface with the minor cutting edge on the other periphery surface to a cutting corner connecting the major cutting edge on the bottom surface with the minor cutting edge on the other periphery surface. This design provides a maximum area for each of the flat contact surfaces in an oblique direction from the cutting corner on the top surface to the cutting corner on the bottom surface.

[0016] In one embodiment of the invention, in a first circumferential direction, each of the contact surfaces is at least partially defined by a first transition surface and in a second circumferential direction, at least partially defined by a second transition surface. The transition surfaces are part of the circumferential surface. Each transition edge is provided at the intersection of the first transition surface with the top surface or the intersection of the second transition surface with the bottom surface. Each transition surface connects the contact surface with a secondary clearance surface of the secondary cutting edge.

[0017] In one embodiment, the extent of the circumferential contact surface at the mid-plane is less than the extent of the contact surface along each of the major cutting edges.

[0018] In one embodiment of the invention, the top and bottom surfaces have a common axis of rotational symmetry, and each of the peripheral surfaces comprises two minor flanks, a first of which intersects the top surface at a minor cutting edge, and a second of which intersects the bottom surface at a minor cutting edge, and each of the minor flanks starting from the minor cutting edge is inclined towards the axis of rotational symmetry. In other words, each of the minor flanks is inclined inwardly towards the axis of rotational symmetry in its extent from the minor cutting edge towards the mid-plane. Thus, when viewed in a section through the minor flanks and including the axis of rotational symmetry, any point on the minor flank close to the minor cutting edge is farther away from the axis of rotational symmetry than any point on the minor flank close to the mid-plane.

[0019] According to this embodiment, the cutting insert is positive with respect to each of the secondary cutting edges. The positive inserts at the secondary cutting edges enable inclined plunge machining with a cutting tool comprising a tool body with at least one indexable cutting insert according to this embodiment. Furthermore, the inclined secondary clearance avoids collisions between the cutting insert and the workpiece while maximizing the area of ​​the flat contact surface.

[0020] In one embodiment of the present invention, each of the minor clearance surfaces is a planar surface.

[0021] In one embodiment of the present invention, each of the triangular top surface and the triangular bottom surface has three-fold symmetry. However, in one embodiment, the top surface and the bottom surface are provided such that the angular positions of the cutting corners of the top surface relative to the angular positions of the cutting corners of the bottom surface are twisted with respect to each other. Furthermore, in this embodiment, the top surface and the bottom surface have a common axis of rotational symmetry. The twisted arrangement of the cutting corners of the top surface and the bottom surface allows for providing a cutting insert with a positive cutting edge with respect to the minor cutting edge.

[0022] In one embodiment of the invention, each of the minor flanks extends from the minor cutting edge to a mid-plane, the mid-plane being intermediate the top and bottom surfaces. The extent of the minor flanks from their respective minor cutting edges to the mid-plane improves the relief of the minor cutting edges. In one embodiment, each of the minor flanks terminates at the mid-plane.

[0023] In one embodiment of the invention, the top surface comprises a flat top support surface and the bottom surface comprises a flat bottom support surface. The provision of flat support surfaces on the top and bottom surfaces in addition to the flat contact surface on the circumferential surface increases the mechanical positioning stability and / or positioning accuracy of the cutting insert when mounted in its seat in the tool body.

[0024] In one embodiment, each of the minor cutting edges of the top surface protrudes beyond the top support surface over the entire length of the minor cutting edge, each of the minor cutting edges of the bottom surface protrudes beyond the bottom support surface over the entire length of the minor cutting edge, each of the major cutting edges of the top surface protrudes at least partially beyond the top support surface, each of the major cutting edges of the top surface inclines from adjacent cutting corners toward the top support surface, the adjacent cutting corners connecting the major cutting edges and the minor cutting edges, each of the major cutting edges of the bottom surface protrudes at least partially beyond the bottom support surface, each of the major cutting edges of the bottom surface inclines from adjacent cutting corners toward the bottom support surface, the adjacent cutting corners connecting the major cutting edges and the minor cutting edges. In other words, the minor cutting edges are elevated above their respective top or bottom surfaces over their entire extent, and at least a portion of each major cutting edge is elevated above their respective top or bottom surfaces. By disposing the cutting edges beyond their respective support surfaces, the area of ​​the flat support surfaces of the top and bottom surfaces is increased.

[0025] In one embodiment of the present disclosure, the top and bottom support surfaces are parallel.

[0026] In one embodiment of the invention, each of the major cutting edges is at least partially elevated above the respective flat support surface and the major cutting edge and the respective flat support surface, i.e. the top support surface or the bottom support surface, form an angle in the range of 5° to 15° or in the range of 8° to 12°, the angle being measured in a plane perpendicular to the respective contact surface, in other words between the cutting edge and a line perpendicular to the respective support surface normal.

[0027] A major cutting edge that is angled relative to the top or bottom support surface allows the cutting insert to be mounted in the tool body such that the major cutting edge provides a positive effective axial angle.

[0028] In one embodiment of the invention, the top and bottom surfaces each comprise a major and a minor chip surface, each of the major cutting edges defines a major chip surface, each of the minor cutting edges defines a minor chip surface, each of the major and each of the minor chip surfaces forms an angle in the range of 0° to 45° with respect to the respective support surface, i.e., the top support surface or the bottom support surface, each of the major chip surfaces is raised in a direction toward the major cutting edge, and each of the minor chip surfaces is raised in a direction toward the minor cutting edge. This design of the chip surfaces strengthens the cutting edges by increasing the wedge angle of each cutting edge that defines the chip surface.

[0029] In one embodiment of the present invention, the angle between each of the minor chip surfaces and the respective top or bottom support surface is constant.

[0030] In one embodiment of the invention, the angle between each of the major chip faces and the respective top or bottom support surface increases or decreases along the major cutting edge, hi one embodiment, the angle between the major chip faces and the respective support surface, i.e., top or bottom support surface, is constant along the major cutting edge.

[0031] In embodiments in which the minor chip faces are inclined relative to the respective support surfaces or in which the minor chip faces are parallel to the respective support surfaces and the minor flank faces are inclined from the minor cutting edge toward the axis of rotational symmetry, the inclination of the minor flank faces provides the minor cutting edge with a positive design.

[0032] In one embodiment of the present invention, each of the minor cutting edges is parallel to the upper support surface.

[0033] In one embodiment of the present invention, each pair of major and minor cutting edges connected by a cutting corner includes an angle in the range of 85° to 95° or 89° to 91° when extended in a plane parallel to the upper support surface. Angles within the claimed ranges are considered to be approximately perpendicular. Upon viewing a cutting insert according to this embodiment, an operator would realize that the cutting insert is suitable for shoulder milling operations that provide a 90° angle between the wall and bottom surfaces of a workpiece.

[0034] In one embodiment, a triangular cutting insert according to the present invention has a major cutting edge and a minor cutting edge, each of the major cutting edges having the same length, each of the minor cutting edges having the same length, and the length of the major cutting edge is at least twice the length of the minor cutting edge. In one embodiment, the length of the major cutting edge is at least three or at least four times the length of the minor cutting edge. Less material is required to provide the same cutting depth as compared to cutting inserts in which the major and minor cutting edges have the same or nearly the same length.

[0035] At least one of the above objects is solved by a shoulder milling tool comprising a tool body, the tool body including a plurality of insert seats and a plurality of indexable cutting inserts according to any one of the embodiments as described above, the cutting inserts being mounted in the insert seats.

[0036] Further advantages, features and applications of the present disclosure will become apparent from the following description of the embodiments and the accompanying drawings. The foregoing description and the following detailed description of the embodiments of the present disclosure will be better understood when read in conjunction with the accompanying drawings. It should be understood that the illustrated embodiments are not limited to the precise arrangements and instrumentalities shown. Unless otherwise indicated, the same reference numerals in different drawings refer to the same or corresponding parts. [Brief description of the drawings]

[0037] [Figure 1] FIG. 1 is a side view of a shoulder milling tool with an indexable cutting insert according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a top view of the indexable cutting insert of FIG. 1. [Diagram 3] FIG. 3 is a side view of the indexable cutting insert of FIGS. 1 and 2. [Figure 4] FIG. 4 is a side view of the indexable cutting insert of FIGS. 1 to 3 rotated 30° when compared to the side view of FIG. 3 . DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] The shoulder milling tool of FIG. 1 is designed for milling a shoulder into a workpiece (not shown), the shoulder having a 90° angle between the wall surface and the bottom surface to be machined into the workpiece.

[0039] The shoulder milling tool 1 comprises a tool body 2 which includes a plurality of seats 3 and, in operation, a plurality of indexable cutting inserts 4 mounted in the seats 3. In Figure 1, only a single indexable cutting insert 4 is shown in the seats 3, the remaining seats 3 are shown without the cutting insert 4.

[0040] Each of the cutting inserts 4 has a triangular basic shape. The cutting inserts 4 have identical upper and lower surfaces 5 and 6, such that a bottom view of the cutting insert 4 is the same as the top view of FIG. 2. Each feature described below with respect to the upper surface 5 can also be described with respect to the bottom surface 6, however.

[0041] The top surface 5 and the bottom surface 6 each have three-fold symmetry. However, the triangles defined by the top surface 5 and the bottom surface 6 are twisted relative to one another such that the angular positions of the corners of the top triangle are different from the angular positions of the corners of the bottom triangle. The triangular top surface 5 and the triangular base surface 6 are connected by three peripheral surfaces 7. Each of the peripheral surfaces 7 extends along a single side of the top surface 5 and along a single side of the bottom surface 6.

[0042] Each of the top and bottom surfaces 5, 6 includes three sets of cutting edges, each set being formed by a major cutting edge 9, a minor cutting edge 10, and a cutting corner 8 connecting the major cutting edge 9 and the minor cutting edge 10. Thus, the cutting insert 4 has a total of six sets of cutting edges. Each of the cutting corners 8 and cutting edges 9, 10 is provided at the intersection of either the top or bottom surface 5, 6 with one of the three peripheral surfaces 7.

[0043] The upper surface 5 comprises a flat upper support surface 11, and each of the secondary cutting edges 10 is elevated over its entire extent above the height defined by the flat support surface 11. A cutting corner 8 connects the elevated secondary cutting edge 10 with the primary cutting edge 9, so that the primary cutting edge 9 is at least partially elevated above the flat support surface 11. However, starting from the cutting corner 8, the primary cutting edge 9 descends completely to a height below the upper support surface 11. This inclination of the primary cutting edge 9 allows the insert 4 to be mounted in the tool body 2 with a positive effective axial angle.

[0044] Due to the elevated geometry, each of the secondary cutting edges 10 includes a secondary chip surface 12 that is similarly elevated above the height defined by the flat support surface 11. Each of the primary cutting edges 9 includes a primary chip surface 13 that is partially elevated above the height defined by the flat support surface 11. The primary chip surface 13 and the secondary chip surface 12 are inclined relative to the support surface 11 such that the primary cutting edges 9 and the secondary cutting edges 10 have a positive wedge angle.

[0045] When the cutting insert 4 is mounted in the insert seat 3 of the tool body 2 of Figure 1, a set of cutting edges is active, comprising a cutting corner 8 and cutting edges 9, 10. The effective secondary cutting edge 10 is perpendicular to the rotation axis 14 of the tool body 2. The effective primary cutting edge 9, which is connected to the effective secondary cutting edge 10 by the cutting corner 8, is perpendicular to the effective secondary cutting edge 10 when extending in a plane parallel to and containing the rotation axis and the secondary cutting edge 10.

[0046] The viewing direction of the side view in Figure 3 is perpendicular to each of the top and bottom main cutting edges 9. Each of the peripheral surfaces 7 has several surface portions.

[0047] Each peripheral surface 7 is provided with a single central flat contact surface 15. Each flat contact surface 15 is defined by a major cutting edge 9 of the top surface 5 and a major cutting edge 9 of the bottom surface 6. Furthermore, each oblique flat contact surface 15 extends from a cutting corner 8 of the top surface 5 to a cutting corner 8 of the bottom surface 6.

[0048] From the side view of Figure 3, it is clear that each major cutting edge 9 of the first set of cutting edges, comprising the corners 8 and cutting edges 9, 10, is connected to the minor cutting edge 10 of the "adjacent" set by a transition edge 16. Thus, each of the top and bottom faces 5 and 6 comprises three transition edges 16. The transition edges 16 terminate the major cutting edges 9 at one end thereof. When extended in the mid-plane, the transition edges 16 form an angle with the major cutting edges 9.

[0049] Since the secondary cutting edge 10 and the main cutting edge 9 are at least partially elevated above the height defined by the support surface 11, a transition edge 16 connecting the main cutting edge 9 to an adjacent secondary cutting edge 10 on the same peripheral surface 7 rises from a height below the support surface 11 to the height defined by the secondary cutting edge 10.

[0050] The contact surface 15 is perpendicular to the support surfaces 11 of both the top surface 5 and the bottom surface 6. The contact surface 15 is therefore perpendicular to a mid-plane located halfway between the top and bottom surfaces. The contact surface 15 forms the clearance surface of the main cutting edge 9. As a result, the cutting insert of Figures 1 to 4 is a negative cutting insert with respect to the main cutting edge 9.

[0051] In the mid-plane, each of the contact surfaces 15 has a circumferential extent that is smaller than the length of the contact surface 15 along the major cutting edge 9 at the location of the major cutting edge 9 that defines the contact surface 15 .

[0052] The contact surface 15 is separated on both sides in the longitudinal, circumferential direction from secondary clearance faces 18 associated with the secondary cutting edges 10 by transition surface portions 17. Each of the secondary clearance faces 18 starts from the respective secondary cutting edge 10 and inclines towards the mid-plane in that area such that the cutting insert 4 becomes a positive insert with respect to the secondary cutting edge 10.

[0053] Each of the major cutting edges 9 has the same overall length and each of the minor cutting edges 10 has the same overall length. When extended in the mid-plane, the overall length of each of the major cutting edges is approximately five times the overall length of each of the minor cutting edges 10. Thus, a circle inscribed in a triangle touches each side of the triangle exactly once. Due to the selected geometry, the inscribed circle touches each of the sides at the major cutting edges 9.

[0054] In the embodiment of Figures 1 to 4, each of the major cutting edge 9 and the minor cutting edge 10 is straight.

[0055] The complex geometry of the cutting insert 4 described above provides the cutting insert 4 with a negative main cutting edge 9 and a positive secondary cutting edge 10. The selected geometry allows a large area of ​​contact surface 15 of the peripheral surface 7, improving the positioning stability of the insert 4 when mounted in the insert seat 3 of the tool body 2. Furthermore, by making the cutting edges 9, 10 and the cutting corners 8 higher than the height of the support surface 11, the area of ​​the support surface 11 is further increased, which further improves the positioning stability of the insert 4 when mounted in the insert seat 3.

[0056] It should be noted that features described in connection with one embodiment may also be used in other embodiments, as can be readily appreciated by those skilled in the art.

[0057] Although the present disclosure has been described in detail with reference to the drawings, the description is by way of example only and is not to be considered as limiting the scope of protection defined by the claims.

[0058] In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" does not exclude a plurality. The mere fact that several features are claimed in different claims does not exclude their combination. Reference numbers in the claims are not to be considered as limiting the scope of protection. [Explanation of symbols]

[0059] 1 Shoulder milling tool 2 Tool body 3 Insert seat 4 Cutting insert 5 Triangular top surface 6. Triangular base 7 Peripheral surface 8 Cutting Corners 9 Main cutting edge 10 Secondary cutting edge 11 Flat support surface 12 Secondary chip surface 13 Main chip surface 14 Rotational Axis 15 Flat contact surface 16 Transition Edge 17 Transition Surface Section 18 Secondary relief face

Claims

1. An indexable cutting insert (4) for mounting in an insert seat (3) in a tool body (2) of a shoulder milling tool (1), comprising: The cutting insert (4) generally comprises: A triangular upper surface (5); A triangular base (6); three peripheral surfaces (7) extending between said top surface (5) and said bottom surface (6); It is defined by On each side of the cutting insert (4), a respective one of the three peripheral surfaces (7) extends along the edge of the upper surface (5) of the triangle and along the edge of the base surface (6) of the triangle, The cutting insert (4) Each of said top surface (5) and said bottom surface has three cutting corners (8), three major cutting edges (9) and three minor cutting edges (10); Each of said cutting corners (8) connects said major cutting edge (9) and said minor cutting edge (10); 1. An indexable cutting insert (4), wherein each of said cutting corners (8), each of said major cutting edges (9) and each of said minor cutting edges (10) are provided at an intersection of said top surface (5) or said bottom surface (6) with one of said peripheral surfaces (7), each of said peripheral surfaces (7) comprises a flat contact surface (15), said flat contact surface (15) being defined by said main cutting edge (9) of said top surface (5) and said main cutting edge (9) of said bottom surface (6); 1. An indexable cutting insert (4), characterized in that said top surface (5) and said bottom surface (6) have a common axis of rotational symmetry, each of said peripheral surfaces (7) comprises two minor clearances (18), a first of said two minor clearances (18) intersects said top surface (5) at said minor cutting edge (10) and a second of said two minor clearances (18) intersects said bottom surface (6) at said minor cutting edge (10), and each of said minor clearances (18) starting from said minor cutting edge (10) is inclined towards said axis of rotational symmetry.

2. The cutting insert (4) has a mid-plane located midway between the top surface (5) and the bottom surface (6), the cutting insert (4) comprises three transition edges (16) on each of the top surface (5) and the bottom surface (6), the transition edges (16) being provided at the intersection of the top surface (5) or the bottom surface (6) with one of the peripheral surfaces (7); Each of said transition edges (16) connects said major cutting edge (9) and said minor cutting edge (10); when said main cutting edges (9) and said transition edges (16) extend on said intermediate plane, each of said transition edges (16) forms an angle with the main cutting edge (9) to which it is connected; When extended on said intermediate plane, each of said main cutting edges (9) is straight and has a total length, said total length being between said cutting corner (8) to which said main cutting edge (9) is connected and said transition edge (16) to which said main cutting edge (9) is connected; each of said flat contact surfaces (15) extends along at least ⅔ of said total length of said main cutting edge (9), said main cutting edge (9) defining said flat contact surface (15) on each of said top surface (5) and said bottom surface (6); An indexable cutting insert (4) according to claim 1.

3. 3. The indexable cutting insert (4) according to claim 2, wherein each of said flat contact surfaces (15) extends along the entire length of said main cutting edge (9).

4. 2. The indexable cutting insert (4) of claim 1, wherein each of the minor clearance surfaces (18) extends from the minor cutting edge (10) to a mid-plane, the mid-plane being located intermediate the top surface (5) and the bottom surface (6).

5. The top surface (5) comprises an upper support surface (11) and the bottom surface (6) comprises a bottom support surface (11); Each of the secondary cutting edges (10) of the top surface (5) projects beyond the upper support surface (11) over the entire length of the secondary cutting edge (10), and each of the secondary cutting edges (10) of the bottom surface (6) projects beyond the bottom support surface (11) over the entire length of the secondary cutting edge (10), each of said main cutting edges (9) of said upper surface (5) at least partially projects beyond said upper support surface (11); each of the major cutting edges (9) of the upper surface (5) is inclined from the adjacent cutting corner (8) towards the upper support surface (11), the adjacent cutting corner (8) connecting the major cutting edge (9) with the minor cutting edge (10); each of said main cutting edges (9) of said bottom surface (6) at least partially projects beyond said bottom support surface (11); each of the main cutting edges (9) of the bottom surface (6) is inclined from the adjacent cutting corner (8) towards the bottom support surface (11), the adjacent cutting corner (8) connecting the main cutting edge (9) with the secondary cutting edge (10); An indexable cutting insert (4) according to any one of claims 1 to 4.

6. 6. The indexable cutting insert (4) according to claim 5, wherein the top surface (5) and the bottom surface (6) respectively comprise a major chip surface (13) and a minor chip surface (12), each of the major cutting edges (9) defining the major chip surface (13) and each of the minor cutting edges (10) defining the minor chip surface (12), each of the major chip surfaces (13) and each of the minor chip surfaces (12) forming an angle in the range of 0° to 45° with respect to the top support surface (11) and the bottom support surface (11), respectively, each of the major chip surfaces (13) being raised in a direction towards the major cutting edge (9) and each of the minor chip surfaces (12) being raised in a direction towards the minor cutting edge (10).

7. The indexable cutting insert (4) according to any one of claims 5 or 6, wherein each of the secondary cutting edges (10) is parallel to an upper support surface (11).

8. 8. The indexable cutting insert (4) according to any one of claims 5 to 7, wherein each pair of the major cutting edge (9) and the minor cutting edge (10) connected by the cutting corner (8) includes an angle in the range of 85° to 95° when extended in a plane parallel to an upper support surface (11).

9. 9. The indexable cutting insert (4) according to any one of claims 1 to 8, wherein each of the major cutting edges (9) has a same overall length and each of the minor cutting edges (10) has a same overall length, the overall length of the major cutting edges (9) being at least twice the overall length of the minor cutting edges (10).

10. 10. A shoulder milling tool (1) comprising a tool body (2), the tool body (2) comprising a plurality of insert seats (3) and a plurality of indexable cutting inserts (4) according to any one of claims 1 to 9, mounted in the insert seats (3).

Images