Bidirectional indexable V-shaped cutting insert and tool holder thereof

Abstract

A bi-directionally indexable V-shaped cutting insert has a first rake face and a second rake face in an insert front face thereof. First and second relief faces connect the first and second rake faces to the first and second converging insert abutment surfaces, respectively. The first cutting edge is located at an intersection of the first rake face and the first relief face. The second cutting edge is located at the intersection of the second rake face and the second relief face. A first relief angle is formed between the first relief face and the first converging insert abutment surface. A second relief angle is formed between the second relief face and the second converging insert abutment surface. The first relief angle and the second relief angle are obtuse angles. In a cutting tool, the bi-directionally indexable V-shaped cutting insert is removably secured in a tool holder by a fastening member.

Description

TECHNICAL FIELD

[0001] The subject matter of the present application relates to the field of turning operations. In particular, it relates to the field of threading, grooving and parting operations. BACKGROUND

[0002] In the field of turning operations, and in particular in the field of metal working, it is known to provide bidirectional indexable V-shaped cutting inserts. Such cutting inserts are for example shown in EP3702074 and JP6937987.

[0003] In particular, EP3702074 relates to an indexable cutting insert for a cutting tool. The cutting insert comprises a first side surface and an opposite second side surface, and a peripheral surface extending between the first side surface and the second side surface. A cutting portion comprises a first cutting surface and an opposite second cutting surface, a relief surface extending between the first cutting surface and the second cutting surface, a first cutting edge between the first cutting surface and the relief surface, and a second cutting edge between the second cutting surface and the relief surface. The cutting portion is bisected by a first plane transverse to the first side surface, and the cutting portion has a bi-concave cross-section transverse to the first plane. It is shown that the first cutting surface and the second cutting surface have a first rake surface and a second rake surface, respectively. Correspondingly, it is shown that the relief surface has a relief surface.

[0004] JP6937987 relates to a double-sided V-shaped cutting insert comprising an insert front face, an insert back face, and a peripheral surface extending between the insert front face and the back face. The peripheral surface further comprises a forward surface, a first converging surface which is a planar surface, and a first rake surface extending between the forward surface and the first converging surface. The peripheral surface further comprises a second converging surface which is a planar surface, and forms a convergence angle f with the first converging surface, satisfying the following condition: 30° ≤ f ≤ 45°. A second rake surface extends between the forward surface and the second converging surface. A bisector plane defining a convergence angle between the first rake surface and the second rake surface, and equidistant from each of the first rake surface and the second rake surface, and the cutting insert has mirror symmetry about the bisector plane at least in a view taken normal to the insert front face. The first rake surface and the second rake surface both face away from the bisector plane. The first rake surface is more inclined towards the bisector plane than the first converging surface, and the second rake surface is more inclined towards the bisector plane than the second converging surface.

[0005] It is an object of the present application to provide a bidirectional indexable V-shaped cutting insert having advantageous geometrical properties as detailed below. SUMMARY

[0006] According to a first aspect of the subject matter of the present application, there is provided a bidirectional indexable V-shaped cutting insert comprising: a first insert side surface and a second insert side surface opposite to the first insert side surface; and a peripheral surface extending between the first insert side surface and the second insert side surface. a blade peripheral surface connecting the first and second blade side surfaces; the blade peripheral surface comprises: a blade rake surface located in the blade cutting portion; a blade flank surface located opposite the blade rake surface and in a blade abutment portion adjacent the blade cutting portion; and first and second converging blade abutment surfaces converging towards each other in a direction away from the blade rake surface and towards the blade flank surface; wherein: the blade rake surface comprises a first rake surface and a second rake surface; and the blade peripheral surface further comprises: a first relief surface connecting the first rake surface and the first converging blade abutment surface; a second relief surface connecting the second rake surface and the second converging blade abutment surface; and first and second cutting edges, the first cutting edge being located at an intersection of the first rake surface and the first relief surface, the second cutting edge being located at an intersection of the second rake surface and the second relief surface. According to a second aspect of the present application there is provided a cutting tool comprising: a bidirectionally indexable V-shaped cutting insert as described above; a clamping member; and a cartridge having a longitudinal axis defining opposite forward and rearward directions, the cartridge comprising: a shank portion and a cartridge cutting portion located forward of the shank portion in the forward direction; opposite cartridge top and bottom faces extending along the longitudinal axis and on opposite sides of the longitudinal axis; opposite cartridge front and back faces extending along the longitudinal axis and on opposite sides of the longitudinal axis, connecting the cartridge top and bottom faces; and a cartridge forward surface located between the top, bottom, front and back faces, bounding the cartridge in the forward direction; the cartridge cutting portion comprises: an insert seat outwardly open to the cartridge front face and the cartridge forward surface, the insert seat comprising: a first converging cartridge abutment surface; a second converging cartridge abutment surface located forward of the first converging cartridge abutment surface; and a main cartridge abutment surface connecting the first and second converging cartridge abutment surfaces.

[0007] It will be appreciated that the above description is a summary and that the features described below can be applied to the present application in any combination, for example, any of the following features can be applied to the bidirectionally indexable V-shaped cutting insert and / or the cutting tool.

[0008] A first clearance angle arl formed between the first clearance face and the first converging tool engagement surface, and a second clearance angle ar2 formed between the second clearance face and the second converging tool engagement surface, can satisfy the following condition: 90° < arl, ar2 < 175°.

[0009] The bidirectional indexable V-shaped cutting insert can include exactly two cutting edges consisting of a first cutting edge and a second cutting edge.

[0010] The first and second converging tool engagement surfaces can be planar.

[0011] The symmetry plane can pass through the first and second insert side surfaces and bisect the bidirectional indexable V-shaped cutting insert. The first cutting edge can exhibit mirror symmetry about the symmetry plane with respect to the second cutting edge.

[0012] The first converging tool engagement surface can exhibit mirror symmetry about the symmetry plane with respect to the second converging tool engagement surface.

[0013] The bidirectional indexable V-shaped cutting insert can exhibit mirror symmetry about the symmetry plane.

[0014] An insert wedge angle awi can be formed between the first converging tool engagement surface and the second converging tool engagement surface. The insert wedge angle awi can satisfy the following condition: 25° < awi < 80°.

[0015] The first and second clearance angles arl, ar2 can satisfy the following condition: 120° < arl, ar2 < 165°.

[0016] The insert rake face can further include a chip deflector protrusion located between the first rake surface and the second rake surface and further away from the insert relief surface than at least a portion of the first rake surface and the second rake surface.

[0017] The first insert side surface can include a first insert engagement sub-surface located in the insert engagement portion and a first cutting sub-surface located in the insert cutting portion. The second insert side surface can include a second insert engagement sub-surface located in the insert engagement portion and a second cutting sub-surface located in the insert cutting portion. An engagement portion thickness Ta defined from the first insert engagement sub-surface to the second insert engagement sub-surface and a cutting portion thickness Tp defined from the first cutting sub-surface to the second cutting sub-surface can satisfy the following condition: Ta > Tp.

[0018] The first cutting sub-surface can comprise a first central region and a first inner region located closer to the first and second cutting edges than the first central region. The second cutting sub-surface can comprise a second central region and a second inner region located closer to the first and second cutting edges than the second central region. The central region thickness Tc (defined as the distance from the first central region to the second central region) and the inner region thickness Ti (defined as the distance from the first inner region to the second inner region) can satisfy the following condition: Ti < Tc.

[0019] The central region thickness Tc can satisfy the following condition: Tc < 2 mm, and the inner region thickness Ti can satisfy the following condition: Ti < Tc.

[0020] The central region thickness Tc can satisfy the following condition: 2 mm ≤ Tc, and the inner region thickness Ti can satisfy the following condition: Ti = Tc.

[0021] The insert wedge angle awi formed between the first converging insert abutment surface and the second converging insert abutment surface, and the insert seat angle asi formed between the first converging holder abutment surface and the second converging holder abutment surface, can satisfy the following condition: 25° ≤ awi, asi ≤ 80°.

[0022] The first holder abutment angle ah1 formed between a first holder normal orthogonal to the first converging holder abutment surface and the longitudinal axis can satisfy the following condition: -10° ≤ ah1 ≤ 10°.

[0023] The second holder abutment angle ah2 formed between a second holder normal orthogonal to the second converging holder abutment surface and the longitudinal axis can satisfy the following condition: 130° ≤ ah2 ≤ 150°.

[0024] The bidirectional indexable V-shaped cutting insert fixed in the insert seat can be bounded in the forward direction by the working cutting edge, which is the one of the first and second cutting edges that is most forward.

[0025] The cutting tool can be bounded in the forward direction by the working cutting edge.

[0026] The bidirectional indexable V-shaped cutting insert can further comprise a through hole opening outwardly to the first and second insert abutment sub-surfaces. The holder's insert seat can further comprise a holder bore opening outwardly to the main holder abutment surface. The first and second converging insert abutment surfaces can each abut one of the first and second converging holder abutment surfaces. One of the first and second insert abutment sub-surfaces can abut the main holder abutment surface. A fastening member can pass through the bidirectional indexable V-shaped cutting insert's through hole, engage with the holder bore, and detachably fix the bidirectional indexable V-shaped cutting insert to the holder. BRIEF DESCRIPTION OF DRAWINGS

[0027] For a better understanding of the present application, and to show how it can be carried into practice, reference will now be made, purely by way of example, to the accompanying drawings in which: Figure 1 is a perspective view of a cutting tool according to an aspect of the present application; Figure 2 is an exploded view of the cutting tool shown in Figure 1 Figure 3 is a perspective view of a bidirectional indexable V-shaped cutting insert shown in Figure 1 Figure 4 is a flipped side view of the bidirectional indexable V-shaped cutting insert shown in Figure 3 Figure 5 is an abutment side view of the bidirectional indexable V-shaped cutting insert shown in Figure 4 Figure 6 is a first side view of the tool holder shown in Figure 1 Figure 7 is a front view of the tool holder shown in Figure 6 Figure 8 is a first side view of the cutting tool shown in Figure 1 Figure 9 is a perspective view of a bidirectional indexable V-shaped cutting insert according to another aspect of the present application; Figure 10 is a flipped side view of the bidirectional indexable V-shaped cutting insert shown in Figure 9 Figure 11 is an abutment side view of the bidirectional indexable V-shaped cutting insert shown in Figure 9 Figure 12 is a perspective view of a cutting tool according to a second aspect of the present application; Figure 13 is a first side view of the cutting tool shown in Figure 12 Figure 14 is a first side view of the tool holder shown in Figure 12

[0028] It should be understood that the elements shown in the figures are not necessarily to scale, especially when illustrated conceptually. For example, the dimensions of some of the elements can be exaggerated relative to others for clarity. Also, one functional block or element can contain several physical components, where appropriate. Where appropriate, reference numbers have been repeated in the drawings to indicate corresponding or analogous elements.DETAILED DESCRIPTION

[0029] ​​​​​​​​​​​In the following description, various aspects of the present application subject matter will be described. For the purpose of explanation, specific configurations and details are set forth in order to provide a thorough understanding of the present application subject matter. However, it will also be understood by those skilled in the art that the present application subject matter can be practiced without the specific configurations and details set forth herein.

[0030] First note that Figure 1 and Figure 2 a cutting tool 1 according to the present application is shown. The cutting tool 1 comprises a bidirectional indexable V-shaped cutting insert 10, a fastening member 80 and a tool holder 100. The bidirectional indexable V-shaped cutting insert 10 is detachably secured to the tool holder 100 by the fastening member 80. The bidirectional indexable V-shaped cutting insert 10 is typically made of a material that is harder than the tool holder 100, such as cemented carbide.

[0031] The bidirectional indexable V-shaped cutting insert 10 is preferably, but optionally, plate-shaped. The bidirectional indexable V-shaped cutting insert 10 can be used in, for example, grooving and parting operations. In particular, the cutting tool 1 can be a Swiss turning tool for use in Swiss machining operations. Swiss turning operations involve complex and high-precision cutting operations, typically with small dimensions, and with a high density of cutting tools placed in a turret. Alternatively, the bidirectional indexable V-shaped cutting insert 10 can have a cutting edge geometry for use in, for example, turning or threading (i.e. straight / oblique / V-shaped / profiled cutting edges).

[0032] As seen in Figures 3 to 5 the bidirectional indexable V-shaped cutting insert 10 comprises an insert abutment portion 11a, an insert cutting portion 11b, a first insert side surface 12, a second insert side surface 20 and an insert peripheral surface 28 connecting the first and second insert side surfaces 12, 20. In side view, as shown in Figure 4 the bidirectional indexable V-shaped cutting insert 10 comprises a narrow end at the bottom of the V-shape and a wider end at the top of the V-shape. The insert abutment portion 11a is provided at the narrow end of the bidirectional indexable V-shaped cutting insert 10 and the insert cutting portion 11b is provided at the wider end of the bidirectional indexable V-shaped cutting insert 10. A symmetry plane S passes through the first and second insert side surfaces 12, 20 and bisects the bidirectional indexable V-shaped cutting insert 10.

[0033] The first and second blade sides 12 and 20 are located on opposite sides of the plane of symmetry S. The first blade side 12 includes a first blade abutment surface 14 located in the blade abutment portion 11a and a first cutting surface 16 located in the blade cutting portion 11b. The second blade side 20 includes a second blade abutment surface 22 located in the blade abutment portion 11a and a second cutting surface 24 located in the blade cutting portion 11b. As described below, when the bidirectional indexable V-shaped cutting blade 10 is fixed to the tool holder 100, one of the first and second blade abutment surfaces 14 and 22 abuts against the tool holder 100. Preferably, but optionally, the first and second blade sides 12 and 20 are identical to each other.

[0034] The cutting portion 11b of the insert includes a first cutting edge 46 and a second cutting edge 48. The first cutting edge 46 and the second cutting edge 48 are located on opposite sides of the plane of symmetry S and are oriented laterally (i.e. not parallel) to the first and second insert side surfaces 12, 20.

[0035] Preferably, but optionally, the insert abutment portion 11a is thicker than the insert cutting portion 11b. For clarity, the abutment portion thickness Ta is defined as the minimum distance from the first insert abutment surface 14 to the second insert abutment surface 22. The cutting portion thickness Tp is defined as the minimum distance from the first cutting surface 16 to the second cutting surface 24. The abutment portion thickness Ta and the cutting portion thickness Tp may satisfy the condition: Ta > Tp. Specifically, the abutment portion thickness Ta and the cutting portion thickness Tp may satisfy the condition: 1.5 * Tp ≤ Ta. The increase in the thickness of the first and second insert abutment surfaces 14, 22 (i.e., the abutment portion thickness Ta) relative to the thickness of the first and second cutting surfaces 16, 24 (i.e., the cutting portion thickness Tp) can strengthen the bidirectional indexable V-shaped cutting insert 10 and, for example, can reduce vibration during machining operations.

[0036] like Figure 5 As shown, in the abutment side view of the bidirectional indexable V-shaped cutting insert 10, the cutting width Wc of the first and second cutting edges 46, 48 is defined as the width of the first and second cutting edges 46, 48 in the direction from one of the first and second insert side surfaces 12, 20 to the other side of the first and second insert side surfaces 12, 20. In some embodiments, the cutting width Wc, the cutting portion thickness Tp, and the abutment portion thickness Ta satisfy the following condition: Ta > Wc > Tp.

[0037] like Figures 9 to 11Another bi-directional indexable V-shaped cutting insert 10' according to the subject application is shown in FIG. 2. For simplicity, features common to both bi-directional indexable V-shaped cutting inserts 10, 10' are numbered identically. First cutting sub-surface 16 of bi-directional indexable V-shaped cutting insert 10' includes a first central region 18a and a first inner region 18b. Similarly, second cutting sub-surface 24 includes a second central region 26a and a second inner region 26b. First and second inner regions 18b, 26b are closer to first and second cutting edges 46, 48 than first and second central regions 18a, 26a. In some embodiments, first and second inner regions 18b, 26b can each be partitioned into separate regions by first and second central regions 18a, 26a, respectively.

[0038] First and second inner regions 18b, 26b are narrower than first and second cutting edges 46, 48 (i.e., cutting width Wc is greater than cutting portion thickness Tp: Wc > Tp). Thus, first and second inner regions 18b, 26b are capable of entering a groove (not shown) being machined in a workpiece during a parting and grooving operation. First and second central regions 18a, 26a can be capable of entering the groove. In other words, while first and second inner regions 18b, 26b are always capable of embedding in a groove machined by the respective cutting edges of first and second cutting edges 46, 48, in some cases first and second central regions 18a, 26a will not be capable of embedding in a groove being machined. For example, the difference in thickness described above can enhance bi-directional indexable V-shaped cutting insert 10' to reduce chatter during a machining operation.

[0039] Thus, in some embodiments, central region thickness Tc (defined as the minimum distance from first central region 18a to second central region 26a) and inner region thickness Ti (defined as the minimum distance from first inner region 18b to second inner region 26b) can satisfy the following condition: Ti < Tc.

[0040] In some embodiments, central region thickness Tc satisfies the following condition: Tc < 2 mm, and inner region thickness Ti satisfies the following condition: Ti < Tc. In these embodiments, first and second central regions 18a, 26a are not capable of embedding in a groove being machined, while first and second inner regions 18b, 26b are capable of embedding in these grooves. Thus, the depth of cut of bi-directional indexable V-shaped cutting insert 10 is limited to the area of first and second inner regions 18b, 26b. For very thin bi-directional indexable V-shaped cutting inserts 10', it can be desirable to find such a difference in thickness in the insert cutting portion 1 lb, as it can stabilize the insert and enhance its ability to resist cutting forces.

[0041] In some embodiments, the central region thickness Tc, the inner region thickness Ti and the cutting width Wc satisfy the following conditions: Tc > Wc > Ti. Such conditions maximize the rigidity of the bidirectional indexable V-shaped cutting insert 10, 10' while still enabling partial embedding of the bidirectional indexable V-shaped cutting insert 10, 10' into a groove being machined by the bidirectional indexable V-shaped cutting insert 10, 10'.

[0042] In some embodiments, for example as seen in Figures 3 to 5 In some embodiments, the central region thickness Tc satisfies the following condition: 2 mm < Tc, and the inner region thickness Ti satisfies the following condition: Ti = Tc. In these embodiments, the first and second central regions 18a, 26a are capable of embedding into a groove being machined. Thus, the depth of cut of the bidirectional indexable V-shaped cutting insert 10 (as compared to embodiments where Tc > Ti) is increased to the entire area of the first and second cutting sub-surfaces 16, 24. For sufficiently thick bidirectional indexable V-shaped cutting inserts 10, it can be desirable to increase the possible depth of cut during a machining operation rather than to enhance the ability of the cutting insert to resist cutting forces (as is done in embodiments where Tc > Ti).

[0043] If the bidirectional indexable V-shaped cutting insert 10 is too thin (particularly the thickness between the first and second cutting sub-surfaces 16, 24), the performance of the cutting tool 1 will be degraded. Thus, when a cutting operation requires the use of a sufficiently thin bidirectional indexable V-shaped cutting insert 10, the depth of cut of the bidirectional indexable V-shaped cutting insert 10 can be reduced to obtain better quality performance (e.g., less chatter or better surface quality). Likewise, if the cutting operation allows for the use of a sufficiently thick bidirectional indexable V-shaped cutting insert 10, there is no need to reduce the depth of cut.

[0044] The first central region 18a and the second central region 26a are positioned opposite one another. Preferably, but optionally, the first central region 18a and the second central region 26a can exhibit mirror symmetry with respect to one another about the plane of symmetry S. Similarly, the first central region 18a can be identical to the second central region 26a. Furthermore, the first central region 18a and the second central region 26a can be parallel to one another.

[0045] Likewise, the first and second inner regions 18b and 26b are opposite one another, and preferably, but optionally, they can exhibit mirror symmetry with respect to one another about the plane of symmetry S. The first inner region 18b can be identical to the second inner region 26b. The first and second inner regions 18b and 26b can also be parallel to one another. It is noted that the first and second inner regions 18b and 26b can be discontinuous. For example, the first and second central regions 18a and 26a can separate the first and second inner regions 18b and 26b, respectively.

[0046] With further reference Figures 3-5 The insert peripheral surface 28 comprises an insert rake face 30, an insert relief face 36, a first converging insert abutment surface 38, a second converging insert abutment surface 42, a first rear relief surface 40 and a second rear relief surface 44. The insert rake face 30 and the insert relief face 36 are opposite each other and connect the first insert side surface 12 and the second insert side surface 20. The insert rake face 30 comprises a first rake land 32a and a second rake land 32b.

[0047] The first and second converging insert abutment surfaces 38, 42 are located on opposite sides of the symmetry plane S. Furthermore, the first and second converging insert abutment surfaces 38, 42 are located between the insert rake face 30 and the insert relief face 36 and converge towards each other in a direction away from the insert rake face 30 and towards the insert relief face 36.

[0048] The first and second rake lands 32a, 32b are provided in the insert rake face 30 to enable the bi-directional indexable V-shaped cutting insert 10 to be seated in a desired orientation with respect to the tool holder 100. During a machining operation, a cutting force generated by machining a rotating workpiece will thus be directed in a direction from the insert rake face 30 to the insert relief face 36 and one of the first and second converging insert abutment surfaces 38, 42. This can be highly advantageous in Y-axis machining (as discussed below). This can further allow machining of workpieces having a large diameter.

[0049] In some embodiments, the first and second converging insert abutment surfaces 38, 42 can intersect the insert relief face 36. Preferably, but optionally, the first and second converging insert abutment surfaces 38, 42 can also intersect the first and second rear relief surfaces 40, 44, respectively.

[0050] To elaborate, a distance from the first converging insert abutment surface 38 to the second converging insert abutment surface 42, when measured proximate the insert rake face 30, is greater than the distance when measured proximate the insert relief face 36. The first converging insert abutment surface 38 and the second converging insert abutment surface 42 connect the first insert side surface 12 and the second insert side surface 20. Preferably, but optionally, the first converging insert abutment surface 38 and the second converging insert abutment surface 42 are planar.

[0051] The first converging insert abutment surface 38 comprises a first converging abutment sub-surface 39a and a first converging cutting sub-surface 39b. The second converging insert abutment surface 42 comprises a second converging abutment sub-surface 43a and a second converging cutting sub-surface 43b. The first and second converging abutment sub-surfaces 39a, 43a are located adjacent the first and second insert abutment sub-surfaces 14, 22. The first and second converging cutting sub-surfaces 39b, 43b are located adjacent the first and second cutting sub-surfaces 16, 24.

[0052] When the cutting insert 1 is assembled, the first and second converging abutment sub-surfaces 39a and 43a abut the holder 100. When the cutting insert 1 is assembled, the first and second converging cutting sub-surfaces 39b and 43b do not necessarily abut the holder 100. Rather, in some embodiments, the first and second converging cutting sub-surfaces 39b, 43b can be located within a recess being machined by the cutting insert 1, while the first and second converging abutment sub-surfaces 39a, 43a cannot be embedded within such a recess.

[0053] Preferably, but optionally, when the cutting insert 1 is assembled, one of the first and second converging cutting sub-surfaces 39b, 43b abuts the holder 100, as will be discussed below.

[0054] The first clearance facet 40 connects the first rake face 32a and the first converging insert abutment surface 38. The second clearance facet 44 connects the second rake face 32b and the second converging insert abutment surface 42. When the cutting insert 1 is assembled, the first and second clearance facets 40, 44 do not abut the holder 100. Preferably, but optionally, the first and second clearance facets 40, 44 are at least partially planar.

[0055] In some embodiments, the first and second clearance facets 40, 44 can comprise first and second sub-clearance facets 41, 45, respectively. The first sub-clearance facet 41 extends from the first cutting edge 46, and the second sub-clearance facet 45 extends from the second cutting edge 48. The first and second sub-clearance facets 41, 45 are preferably, but optionally, at least partially planar.

[0056] A first sub-clearance angle afl is formed between the first clearance facet 40 and the first sub-clearance facet 41. A second sub-clearance angle af2 is formed between the second clearance facet 44 and the second sub-clearance facet 45. Preferably, but optionally, the first and second sub-clearance angles afl, af2 satisfy the following condition: afl = af2. In particular, the first and second sub-clearance angles afl, af2 can satisfy the following condition: 4° < afl, af2 < 12°. More particularly, the first and second sub-clearance angles afl, af2 can satisfy the following condition: 5° < afl, af2 < 8°.

[0057] In side view (only shown in Figure 10 , but equally applicable to Figure 4In some embodiments, the first and second relief surfaces 40, 44 extend transversely (i.e. non-parallel) to the first and second converging insert abutment surfaces 38, 42, respectively. In other words, a first insert clearance angle arl is formed internally between the first relief surface 40 and the first converging insert abutment surface 38, and a second insert clearance angle ar2 is formed internally between the second relief surface 44 and the second converging insert abutment surface 42.

[0058] The bidirectionally indexable V-shaped cutting insert 10, 10' includes exactly two cutting edges formed by a first cutting edge 46 and a second cutting edge 48. The first cutting edge 46 is located at the intersection of the first rake surface 32a and the first relief surface 40. The second cutting edge 48 is located at the intersection of the second rake surface 32b and the second relief surface 44.

[0059] During a turning operation, one of the first and second cutting edges 46, 48 is in working condition and performs the cutting of the workpiece (not shown) being machined. The one of the first and second cutting edges 46, 48 in working condition during machining can be interchangeably referred to as the working cutting edge 50.

[0060] In some embodiments, the first and second relief surfaces 40, 44 extend transversely (i.e. non-parallel) to the first and second converging insert abutment surfaces 38, 42, respectively. In other words, a first insert clearance angle arl is formed internally between the first relief surface 40 and the first converging insert abutment surface 38, and a second insert clearance angle ar2 is formed internally between the second relief surface 44 and the second converging insert abutment surface 42.

[0061] In some embodiments, the first and second insert clearance angles arl, ar2may satisfy the following condition: 90° < arl, ar2< 175°. The first and second insert clearance angles arl, ar2may also satisfy the following condition: arl= ar2. Preferably, the first and second insert clearance angles arl, ar2may satisfy the following condition: 120° < arl, ar2< 165°. More preferably, the first and second insert clearance angles arl, ar2may satisfy the following condition: 135° < arl, ar2< 155°. The first and second insert clearance angles arl, ar2have an effect on the way the insert is positioned with respect to the holder 100. In order to facilitate cutting, the cutting insert has a relief (i.e. has a distance / pitch) between the workpiece being machined and the cutting insert (the angle between the direction of the cutting force during the machining operation and the adjacent clearance surface is typically not more than 10°). Thus, the bidirectional indexable V-shaped cutting insert 10, 10' is positioned to ensure that a relief is maintained between the workpiece and the one of the first clearance surface 40 and the second clearance surface 44 that is closer to the working cutting edge 50. Thus, for different values of the first and second insert clearance angles arl, ar2, the bidirectional indexable V-shaped cutting insert 10, 10' must be differently located in the holder 100 to allow for the relief between the clearance surface and the workpiece. The above conditions for the first and second insert clearance angles arl, ar2thus define the desired positioning of the bidirectional indexable V-shaped cutting insert 10, 10' with respect to the holder 100.

[0062] In some embodiments, the insert rake face 30 can further comprise a chip deflection protrusion 34. The chip deflection protrusion 34 is located between the first rake surface 32a and the second rake surface 32b. The chip deflection protrusion 34 is also positioned further away from the insert back face 36 than at least a portion of the first and second rake surfaces 32a, 32b as exemplified by the deflection line I-I (as shown) that intersects the chip deflection protrusion 34 and connects the two portions of the first and second rake surfaces 32a, 32b. Figure 4

[0063] Preferably, but optionally, the chip deflection protrusion 34 intersects the deflection line I-I when connecting the portions of the first and second rake surfaces 32a, 32b that are adjacent to the first and second cutting edges 46, 48, respectively. That is, the chip deflection protrusion 34 is preferably, but optionally, located at the farthest position from the insert back face 36.

[0064] The chip deflection protrusion 34 extending out from the insert back face 36 and located between the first and second rake surfaces 32a, 32b can ensure that the chip cut from the workpiece being machined by the first cutting edge 46 (when the first cutting edge 46 is the working cutting edge 50) does not affect the second cutting edge 48 during the machining operation.

[0065] ​The cutting forces generated by the cutting tool 1 machining a workpiece generally point in a direction from the rake face 30 to the relief face 36, and the resulting chips are guided along the rake face 30, in particular along one of the first and second rake faces 32a, 32b. The first and second clearance faces 40 and 44 are inclined so as to leave a necessary clearance from the workpiece during operation. This can make it possible to machine workpieces having a large diameter, and the directionality of the cutting forces during the machining operation can further secure the bi-directional indexable V-shaped cutting insert 10, 10' in the tool holder 100.

[0066] This can also make it possible to position the bi-directional indexable V-shaped cutting insert 10, 10' in the tool holder 100 during the machining operation such that it is bounded in the longitudinal direction of the cutting tool 1 by the working cutting edge 50. In a Swiss machining operation, it can be desirable to have the working cutting edge 50 bound the bi-directional indexable V-shaped cutting insert 10, 10' as prescribed. Further advantages can include, for example, that the cutting forces can wedge the bi-directional indexable V-shaped cutting insert 10, 10' into the tool holder 100, which can result in better stability of the cutting tool 1 during the cutting operation.

[0067] The symmetry plane S can bisect the insert wedge angle awi formed between the first converging insert abutment surface 38 and the second converging insert abutment surface 42. The insert wedge angle awi is internal to the bi-directional indexable V-shaped cutting insert 10, 10'. More specifically, the symmetry plane S can be perpendicular to the first and second insert side surfaces 12, 20.

[0068] In some embodiments, the first cutting edge 46 can be mirror-symmetrical about the symmetry plane S with respect to the second cutting edge 48. Further, the first converging insert abutment surface 38 can be mirror-symmetrical about the symmetry plane S with respect to the second converging insert abutment surface 42. Additionally, the bi-directional indexable V-shaped cutting insert 10, 10' can be mirror-symmetrical about the symmetry plane S.

[0069] In some embodiments, the insert wedge angle awi can satisfy the following condition: 25° < awi < 80°. In particular, the insert wedge angle awi can satisfy the following condition: 30° < awi < 70°. More specifically, the insert wedge angle awi can satisfy the following condition: 35° < awi < 55°. An insert wedge angle awi that is too large can result in a reduced strength of the connection between the bi-directional indexable V-shaped cutting insert 10, 10' and the tool holder 100, for example, which can result in increased vibrations during the machining operation. An insert wedge angle awi that is too small can result in the bi-directional indexable V-shaped cutting insert changing its cutting edge height with respect to the workpiece, for example, due to deflection of the tool holder 100.

[0070] Reference is now made to Figures 6 to 8The tool holder 100 has a longitudinal axis L. The longitudinal axis L defines opposite forward and rearward directions Df, Dr (i.e. directions parallel to the longitudinal axis L). The tool holder 100 includes a shank portion 102, a tool holder cutting portion 104, a tool holder top face 106, a tool holder bottom face 108, a tool holder front face 110, a tool holder back face 112, and a tool holder forward face 114.

[0071] The shank portion 102 is fixed in a tool turret during a machining operation. The tool holder cutting portion 104 is located in the forward direction Df from the shank portion 102 and includes a blade seat 120 for securing a bi-directionally indexable V-shaped cutting insert 10, 10' thereto. The tool holder top, bottom, front, back, and forward faces 106, 108, 110, 112, 114 can span both the shank portion 102 and the tool holder cutting portion 104.

[0072] The tool holder top and bottom faces 106, 108 are opposite one another about the longitudinal axis L (i.e. on opposite sides of the longitudinal axis L). The tool holder top and bottom faces 106, 108 can extend along the longitudinal axis L (i.e. lengthwise along the longitudinal axis L). The tool holder front and back faces 110, 112 are opposite one another about the longitudinal axis L and connect the tool holder top and bottom faces 106, 108. The tool holder front and back faces 110, 112 can also extend along the longitudinal axis L. The tool holder forward face 114 is located between the tool holder top, bottom, front, and back faces 106, 108, 110, 112 and bounds the tool holder 100 in the forward direction Df. Preferably, but optionally, the tool holder forward face 114 also connects the tool holder top, bottom, front, and back faces 106, 108, 110, 112.

[0073] In some embodiments, the tool holder top, bottom, front, back, and forward faces 106, 108, 110, 112, 114 can each be planar surfaces. The tool holder top and bottom faces 106, 108 can be parallel to one another. The tool holder front and back faces 110, 112 can be parallel to one another and perpendicular to the tool holder top and bottom faces 106, 108. The tool holder forward face 114 can be perpendicular to the tool holder top, bottom, front, and back faces 106, 108, 110, 112.

[0074] The blade seat 120 is outwardly open to the tool holder front and forward faces 110, 114. Preferably, but optionally, the blade seat is further outwardly open to the tool holder top face 106. The blade seat 120 includes a first converging tool holder abutment surface 122, a second converging tool holder abutment surface 126, and a main tool holder abutment surface 130. The main tool holder abutment surface 130 connects the first and second converging tool holder abutment surfaces 122, 126. Preferably, but optionally, the main tool holder abutment surface 130 extends parallel to the longitudinal axis L. The main tool holder abutment surface 130 can also extend parallel to the tool holder front and back faces 110, 112.

[0075] In some embodiments, the first converging tool post abutment surface 122 may face forward (i.e., towards the forward direction Df). Similarly, the second converging tool post abutment surface 126 may face backward (i.e., towards the rearward direction Dr) and is located in front of the first converging tool post abutment surface 122. In this orientation, the bidirectional indexable V-shaped cutting inserts 10, 10' mounted in the tool post 100 are connected in such a way that the cutting force generated by the cutting tool 1 during the machining operation points transversely to the longitudinal axis L. This is known in the industry as X-axis cutting operation.

[0076] In a cutting operation known as a "Y-axis" cutting operation, the cutting force generated by the cutting operation points along the length of the cutting tool (i.e., along its longitudinal axis).

[0077] In some embodiments, such as in Figures 12 to 14 As shown, the cutting tool 1' can be used in Y-axis operation. The cutting tool 1' includes a bidirectional indexable V-shaped cutting insert 10'' and a tool holder 100'. The bidirectional indexable V-shaped cutting insert 10'' and the tool holder 100'' are connected in such a way that the cutting force generated during the machining operation points along the longitudinal axis L (i.e., Y-axis cutting operation).

[0078] The bidirectional indexable V-shaped cutting insert 10'' can be the same as the aforementioned bidirectional indexable V-shaped cutting inserts 10, 10'. The tool holder 100' is manufactured to facilitate Y-axis cutting operations. Specifically, the first converging tool holder abutment surface 122 can be located closer to the tool holder top surface 106 than the second converging tool holder abutment surface 126. This orientation of the first and second converging tool holder abutment surfaces 122 and 126 will allow for better positioning and assembly of the bidirectional indexable V-shaped cutting insert 10'' for Y-axis machining. The first converging tool holder abutment surface 122 can also be opposite the second converging tool holder abutment surface 126 about the longitudinal axis L.

[0079] In some embodiments, the bidirectional indexable V-shaped cutting inserts 10, 10', 10'' may further include through holes 60 opening outward to the first and second insert sidewalls 12, 20. Specifically, the through holes 60 open outward to the first and second insert abutment surfaces 14, 22. The insert holder 120 may also include a tool holder hole 150 opening outward to the main tool holder abutment surface 130. The fastening member 80 may be a screw 80 having a screw head 82 and a threaded portion 84. Different fastening members are also possible, such as clamping fastening members (not shown) and bayonet-type fastening members (not shown).

[0080] When the bidirectional indexable V-shaped cutting insert 10, 10', 10" is secured to the tool holder 100, 100', the bidirectional indexable V-shaped cutting insert 10, 10', 10" is placed in the insert seat 120. One of the first and second insert abutment surfaces 14, 22 abuts the main tool holder abutment surface 130. Each of the first and second converging abutment surfaces 39a, 43a abuts a different one of the first and second converging tool holder abutment surfaces 122, 126. Preferably, but optionally, one of the first and second cutting sub-surfaces 39b, 43b, in particular the one farthest from the working cutting edge 50, also abuts the first converging tool holder abutment surface 122. This can help to better support the bidirectional indexable V-shaped cutting insert 10, 10', 10" secured to the tool holder 100, 100'.

[0081] The securing member 80 can pass through the through-hole 60 of the bidirectional indexable V-shaped cutting insert 10, 10', 10", engage the tool holder bore 150, and releasably secure the bidirectional indexable V-shaped cutting insert 10, 10', 10" to the tool holder. In particular, in embodiments where the securing member 80 is a screw, the threaded portion 84 passes through the through-hole 60 and engages the tool holder bore 150. The screw head 82 abuts the bidirectional indexable V-shaped cutting insert 10, 10', 10" and secures it to the tool holder 100, 100'.

[0082] In some embodiments, when the bidirectional indexable V-shaped cutting insert 10, 10', 10" is secured to the insert seat 120 of the tool holder 100, 100', it is preferably, but optionally, defined in the forward direction Df by the working cutting edge 50. It is preferably, but optionally, the cutting tool 1 that is defined in the forward direction by the working cutting edge 50. In Swiss machining operations, it can be desirable to have no protrusion in the forward direction from the working cutting edge 50.

[0083] In some embodiments, the insert seat angle asi defined outside the tool holder 100, 100', from the first converging tool holder abutment surface 122 to the second converging tool holder abutment surface 126, can satisfy the following condition: asi = awi.

[0084] The insert seat angle asi can satisfy the following condition: 25° < asi < 80°. The insert seat angle asi can also satisfy the following condition: 30° < asi < 70°. In particular, the insert seat angle asi can satisfy the following condition: 35° < asi < 55°.

[0085] In some embodiments, a first tool holder abutment angle ah1 formed between a first tool holder normal line N1 normal to (i.e. perpendicular to) the first converging tool holder abutment surface 122 and the longitudinal axis L can satisfy the following condition: -10° < ah1 < 10°.

[0086] In some embodiments, a second tool holder abutment angle ahi formed between a second tool holder normal N2 normal to the second converging tool holder abutment surface 126 and the longitudinal axis L can satisfy the following condition: 30° < ahi < 50°. For higher values of the second tool holder abutment angle ahi, the cutting forces generated during the X-axis machining operation can cause excessive strain on the second converging tool holder abutment surface 126 that directly supports the bi-directional indexable V-shaped cutting insert 10, 10', 10" to resist the cutting forces. Alternatively, for lower values of the second tool holder abutment angle ahi, the cutting forces generated during the X-axis machining operation can cause the first and second converging tool holder abutment surfaces 122, 126 to separate. It is noted that the first and second tool holder abutment angles ahi, ahi2 and the insert seat angle asi are related to each other. The angles ensure that the insert seat 120 is rigid. Furthermore, the angles also ensure the rigidity of the second converging tool holder abutment surface 126.

[0087] In some embodiments, the tool holder 100, 100' comprises a coolant outlet 116 fluidly connected to the coolant inlet 117. The coolant outlet 116 and the coolant inlet 117 can be connected by a coolant channel 118. The coolant outlet 116 can be located directly below the active cutting edge 50 (i.e. a straight line perpendicular to the longitudinal axis L that passes through both the active cutting edge 50 and the coolant outlet 116). Due to the orientation of the bi-directional indexable V-shaped cutting insert 10, 10', 10" in the tool holder 100, 100' - the active cutting edge 50 bounds the bi-directional indexable V-shaped cutting insert 10, 10', 10" in the forward direction Df - this allows for direct access to the coolant / lubricant from below.

[0088] While the subject matter of the present application has been described in detail with respect to specific aspects thereof, it will be understood that various changes and modifications can be made without departing from the spirit or scope of the application as claimed below.

Claims

1. A bidirectional indexable V-shaped cutting insert (10, 10', 10''), comprising: The first blade side (12) and the second blade side (20) located opposite to the first blade side (12); as well as The blade peripheral surface (28) connects the sides (12, 20) of the first and second blades; The peripheral surface (28) of the blade includes: The front side (30) of the blade is located in the cutting part (11b); Located opposite the front side (30) of the blade and in the blade abutment portion (11a), the blade abutment portion (11a) is adjacent to the blade cutting portion (11b); and The first and second converging blade abutment surfaces (38, 42) converge toward each other in a direction away from the front (30) and toward the back (36) of the blade. in: The front side of the blade (30) includes a first rake face (32a) and a second rake face (32b); The peripheral surface (28) of the blade also includes: A first clearance surface (40) connecting the first rake face (32a) and the first converging insert abutment surface (38); The second clearance surface (44) connecting the second rake face (32b) and the second converging insert abutment surface (42); and The first cutting edge (46) and the second cutting edge (48) are located at the intersection of the first rake face (32a) and the first clearance face (40), and the second cutting edge (48) is located at the intersection of the second rake face (32b) and the second clearance face (44).

2. The bidirectional indexable V-shaped cutting insert (10, 10', 10'') according to claim 1, wherein: The first clearance angle (ar1) formed between the first clearance surface (40) and the first converging blade abutment surface (38), and the second clearance angle (ar2) formed between the second clearance surface (44) and the second converging blade abutment surface (42), satisfy the following condition: 90° <ar1,ar2<175°。 3. The bidirectional indexable V-shaped cutting insert (10, 10', 10'') according to any one of claims 1 and 2, wherein: The bidirectional indexable V-shaped cutting insert (10, 10', 10'') comprises exactly two cutting edges, consisting of a first cutting edge and a second cutting edge (46, 48).

4. The bidirectional indexable V-shaped cutting insert (10, 10', 10'') according to any one of the preceding claims, wherein: The plane of symmetry (S) passes through the sides (12, 20) of the first and second inserts and bisects the bidirectional indexable V-shaped cutting insert (10, 10', 10''); and The first cutting edge (46) is mirror-symmetric with respect to the second cutting edge (48) about the plane of symmetry (S).

5. The bidirectional indexable V-shaped cutting insert (10, 10', 10'') according to claim 4, wherein: The blade contact surface (38) of the first converging edge is mirror-symmetric about the plane of symmetry (S) relative to the blade contact surface (42) of the second converging edge.

6. The bidirectional indexable V-shaped cutting insert (10, 10', 10'') according to claim 5, wherein: The bidirectional indexable V-shaped cutting inserts (10, 10', 10'') are mirror-symmetric about the plane of symmetry (S).

7. The bidirectional indexable V-shaped cutting insert (10, 10', 10'') according to any one of the preceding claims, wherein: The blade wedge angle awi formed between the first converging blade abutment surface (38) and the second converging blade abutment surface (42) satisfies the following condition: 25°≤awi≤80°.

8. The bidirectional indexable V-shaped cutting insert (10, 10', 10'') according to any one of the preceding claims, wherein: The first rear angle ar1 and the second rear angle ar2 satisfy the following conditions: 120°≤ar1, ar2≤165°.

9. The bidirectional indexable V-shaped cutting insert (10, 10', 10'') according to any one of the preceding claims, wherein: The front side of the blade (30) also includes a chip deflection protrusion (34) located between the first rake face (32a) and the second rake face (32b), and further away from the back side of the blade (36) than at least a portion of the first rake face (32a) and the second rake face (32b).

10. The bidirectional indexable V-shaped cutting insert (10, 10', 10'') according to any one of the preceding claims, wherein: The first blade side surface (12) includes a first blade abutting sub-surface (14) located in the blade abutting portion (11a) and a first cutting sub-surface (16) located in the blade cutting portion (11b). The second blade side surface (20) includes a second blade abutting sub-surface (22) located in the blade abutting portion (11a) and a second cutting sub-surface (24) located in the blade cutting portion (11b). The abutment portion thickness Ta defined from the first blade abutment surface (14) to the second blade abutment surface (22), and the cutting portion thickness Tp defined from the first cutting surface (16) to the second cutting surface (24), satisfy the following condition: Ta > Tp.

11. The bidirectional indexable V-shaped cutting insert (10, 10', 10'') according to claim 10, wherein: The first cutting surface (16) includes a first central region (18a) and a first inner region (18b), the first inner region being located closer to the first and second cutting edges (46, 48) than the first central region (18a). The second cutting surface (24) includes a second central region (26a) and a second inner region (26b), the second inner region being located closer to the first and second cutting edges (46, 48) than the second central region (26a); and The central region thickness Tc, defined as the distance from the first central region (18a) to the second central region (26a), and the internal region thickness Ti, defined as the distance from the first internal region (18b) to the second internal region (26b), satisfy the following condition: Ti≤Tc.

12. The bidirectional indexable V-shaped cutting insert (10') according to claim 11, wherein: The thickness Tc of the central region must satisfy the following condition: Tc < 2 mm; The thickness Ti of the internal region satisfies the following condition: Ti <Tc。 13. The bidirectional indexable V-shaped cutting insert (10, 10'') according to claim 11, wherein: The thickness Tc of the central region satisfies the following condition: 2 mm ≤ Tc; The thickness Ti of the internal region satisfies the following condition: Ti = Tc.

14. A cutting tool (1, 1'), comprising: Bidirectional indexable V-shaped cutting inserts (10, 10', 10'') according to any of the preceding claims; Fastening component (80); and A tool holder (100, 100') having a longitudinal axis (L), the tool holder defining opposing forward and backward directions (Df, Dr), the tool holder comprising: The shank portion (102) and the tool holder cutting portion (104) located in the forward direction (Df) from the shank portion (102). The tool holder top surface and tool holder bottom surface (106, 108) extend along the longitudinal axis (L) and are located on opposite sides of the longitudinal axis (L). Extending along the longitudinal axis (L) and on opposite sides of the longitudinal axis (L) are opposing tool holder front and back faces (110, 112), the tool holder front and back faces connecting the tool holder top surface and the tool holder bottom surface (106, 108). The tool holder has a forward surface (114) located between the top surface, bottom surface, front surface and back surface (106, 108, 110, 112) and defines the tool holder (100, 100') in the forward direction (Df). The tool holder cutting section (104) includes: A blade holder (120) opening outwards to the front of the tool holder and the forward surface (110, 114) of the tool holder, the blade holder (120) comprising: The first converging tool holder abutment surface (122); The second converging tool holder abutment surface (126) located in front of the first converging tool holder abutment surface (122); and The main tool post abutment surface (130) connects the first and second converging tool post abutment surfaces (122, 126).

15. The cutting tool (1, 1') according to claim 14, wherein: The blade wedge angle awi formed between the first converging blade abutment surface (38) and the second converging blade abutment surface (42), and the blade seat angle asi formed between the first converging tool holder abutment surface (122) and the second converging tool holder abutment surface (126), satisfy the following conditions: 25°≤awi, asi≤80°.

16. The cutting tool (1, 1') according to any one of claims 14 and 15, wherein: The first tool post contact angle ah1 formed between the first tool post normal (N1) and the longitudinal axis (L) of the first tool post contact surface (122) orthogonal to the first convergence satisfies the following condition: -10°≤ah1≤10°.

17. The cutting tool (1, 1') according to any one of claims 14 to 16, wherein: The second tool post contact angle ah2 formed between the second tool post normal (N2) and the longitudinal axis (L) of the tool post contact surface (126) orthogonal to the second convergence satisfies the following condition: 130°≤ah2≤150°.

18. The cutting tool (1, 1') according to any one of claims 14 to 17, wherein: The bidirectional indexable V-shaped cutting inserts (10, 10', 10'') fixed in the insert holder (120) are defined in the forward direction (Df) by working cutting edges (50), which are the foremost cutting edges among the first and second cutting edges (46, 48).

19. The cutting tool (1, 1') according to claim 18, wherein: The cutting tool (1, 1') is defined by the working cutting edge (50) in the forward direction (Df).

20. The cutting tool (1, 1') according to claim 14, wherein: The bidirectional indexable V-shaped cutting inserts (10, 10', 10'') also include through holes (60) that open outward to the first and second insert abutment surfaces (14, 22). The blade holder (120) of the tool holder (100, 100') also includes a tool holder hole (150) that opens outward to the main tool holder abutment surface (130). The first and second converging blade abutment surfaces (38, 42) each abut against one of the first and second converging blade holder abutment surfaces (122, 126); One of the first and second blade abutting surfaces (14, 22) abuts against the main blade holder abutting surface (130); The fastening member (80) passes through the through hole (60) of the bidirectional indexable V-shaped cutting insert (10,10',10''), engages with the tool holder hole (150), and detachably fixes the bidirectional indexable V-shaped cutting insert (10,10',10'') to the tool holder (100,100').

Images