Manufacturing method for cutting inserts, cutting tools, and machined products

Abstract

A cutting insert based on one embodiment of the present disclosure has a cutting part having a first surface, a second surface, a third surface positioned between the first and second surfaces, and a flow path extending from the first surface toward the second surface. The flow path has an outflow port that opens in the first surface, and a first flow path that extends from the outflow port toward the second surface. In a first cross-section that passes through the central axis of the first flow path and is orthogonal to the first surface, the width of the first flow path in a direction parallel to the first surface increases with increasing distance from the first surface.

Description

Cross-reference to related applications

[0001] This application claims the priority of Japanese Patent Application No. 2022-151559 filed on September 22, 2022, and incorporates the entire disclosure of the prior application herein by reference.

Technical Field

[0002] This aspect relates to a cutting insert, a cutting tool, and a method for manufacturing a machined product.

Background Art

[0003] As a cutting insert of a cutting tool used for machining a workpiece, for example, the cutting inserts described in Japanese Patent Application Laid-Open No. 5-116008 (Patent Document 1) and International Publication No. 2021 / 074979 (Patent Document 2) are known. The cutting inserts described in Patent Document 1 and Patent Document 2 have a flow path inside through which a coolant for cooling the cutting insert flows.

[0004] Since a flow path is provided inside the cutting insert, it is possible to efficiently supply the coolant to the cutting edge during cutting, thereby enhancing the durability of the cutting insert.

[0005] When a flow path is provided inside the cutting insert, it is required to supply the coolant more efficiently to the cutting edge during cutting.

Summary of the Invention

[0006] A cutting insert according to one aspect of the present disclosure , the has a cutting portion having a first surface, a second surface located on the opposite side of the first surface, a third surface located between the first surface and the second surface, and a flow path extending from the first surface toward the second surface. The flow path has an outlet opening on the first surface, a first flow path extending from the outlet toward the second surface, Place and A second channel extending from the first channel toward the second surface, has. The first channel includes a first channel wall located near the third surface and a second channel wall facing the first channel wall.In a first cross-section passing through the central axis of the first flow channel and perpendicular to the first surface, the width of the first flow channel in the direction parallel to the first surface increases as it moves away from the first surface. In a second cross-section passing through the central axis of the second flow channel and perpendicular to the first surface, the wall of the second flow channel has a first recess in the portion connected to the second flow channel. [Brief explanation of the drawing]

[0007] [Figure 1] This is a perspective view showing a cutting insert according to the first embodiment. [Figure 2] Figure 1 is a plan view of the cutting insert as seen from direction A1. [Figure 3] This is a magnified view of region B1 shown in Figure 1. [Figure 4] This is an enlarged view of region B2 shown in Figure 2. [Figure 5] Figure 4 is an enlarged view of the VV cross-section. [Figure 6] This figure shows a modified example of the first channel of the cutting insert according to the first embodiment, and corresponds to Figure 5. [Figure 7] Figure 5 is an enlarged view of region B3. [Figure 8] Figures 4 and 5 show enlarged views of the VII-VII section. [Figure 9] Figures 4 and 5 show enlarged views of the VIII-VIII section. [Figure 10] This is an enlarged view showing a cutting insert according to the second embodiment, and corresponds to Figure 3. [Figure 11] This is an enlarged view showing a cutting insert according to the second embodiment, and corresponds to Figure 4. [Figure 12] Figure 11 is an enlarged view of the XI-XI cross section, corresponding to Figure 5. [Figure 13] Figures 11 and 12 show enlarged views of the XII-XII section, corresponding to Figure 8. [Figure 14] Figures 11 and 12 show enlarged views of the XIII-XIII section, corresponding to Figure 9. [Figure 15] A side view showing a cutting tool according to an embodiment of the present disclosure. [Figure 16] This figure shows one step in the method for manufacturing a machined workpiece according to an embodiment of the present disclosure. [Figure 17] This figure shows one step in the method for manufacturing a machined workpiece according to an embodiment of the present disclosure. [Figure 18] This figure shows one step in the method for manufacturing a machined workpiece according to an embodiment of the present disclosure. [Modes for carrying out the invention]

[0008] <Cutting inserts> Hereinafter, cutting inserts of non-limiting embodiments of this disclosure (hereinafter sometimes referred to as "inserts") will be described in detail with reference to the drawings. Specifically, cutting inserts of the first and second embodiments will be described in detail with reference to the drawings. However, for the sake of clarity, the drawings referenced below show only the main components necessary to explain the inserts according to each embodiment in a simplified manner. Therefore, the inserts of this disclosure may include any components not shown in the drawings referenced. Furthermore, the dimensions of the components in each drawing do not faithfully represent the dimensions of the actual components or the dimensional ratios of each component.

[0009] In the following explanation, the insert according to the first embodiment will be referred to as insert 1A, and the insert according to the second embodiment will be referred to as insert 1B. However, for the sake of clarity, when describing common configurations between the two, both insert 1A and insert 1B will be referred to as insert 1.

[0010] As shown in Figure 1, an insert 1A according to the first embodiment comprises a first surface 3 (top surface), a second surface 5 (bottom surface) located opposite the first surface 3, and a third surface 7 (side surface) located between the first surface 3 and the second surface 5.

[0011] The first face 3 and the second face 5 are polygonal, and in a non-limiting example shown in FIG. 2, they are rhombic. Therefore, the first face 3 in a non-limiting example shown in FIG. 2 has four corners 9 and four sides 11. Further, in the insert 1A in a non-limiting example shown in FIG. 2, the third face 7 has four faces, and each face is substantially rectangular.

[0012] In a non-limiting example shown in FIG. 2, the first face 3 has a plurality of corners 9 and a plurality of sides 11. Specifically, the first face 3 has a first corner 9A, a second corner 9B, and a third corner 9C. The first corner 9A is one of the plurality of corners 9. The second corner 9B and the third corner 9C are each located adjacent to the first corner 9A among the plurality of corners 9. Further, the first face 3 has a first side 11A extending from the first corner 9A to the second corner 9B, and a second side 11B extending from the first corner 9A to the third corner 9C.

[0013] Here, FIG. 2 is a plan view of the cutting insert 1A shown in FIG. 1 as viewed from the A1 direction, and is a view of the first face 3 in a front view. Hereinafter, the front view of the first face 3 may be alternatively referred to as a top view. In FIG. 2, the second corner 9B is located on the right side of the insert 1, and the third corner 9 C is located on the left side of the insert 1, but it may be the reverse. <000​​​​​​​​ In the example shown in Figure 3, the first cutting edge 13A and the second cutting edge 13B are linear in shape because they are located along the first side 11A and the second side 11B, respectively. The first corner cutting edge 13C is curved in shape because it is located along the first corner 9A. In this case, the radius of curvature of the first corner cutting edge 13C may be constant. Also, in the example shown in Figure 3, since the insert 1 has the cutting edge 13 between the first surface 3 and the third surface 7, the first surface 3 has a rake face region 15 and the third surface 7 has a flank face region 17.

[0017] In one example not limited to Figure 3, the insert 1 has a land surface 19 located between the first surface 3 and the third surface 7. Here, the land surface 19 is a band-shaped surface region provided along the cutting edge 13 to suppress chipping of the cutting edge 13. In one example not limited to Figure 2, for manufacturing purposes, the insert 1 has a surface with the same shape as the land surface 19 even in the parts where the cutting edge 13 is not located.

[0018] The cutting edge 13 may, but is not limited to, be located at the intersection of the first surface 3 and the third surface 7. For example, as described above, if the insert 1 has a land surface 19 or a surface with a similar shape to the land surface 19, the cutting edge 13 may be located at the intersection of the land surface 19 and the third surface 7.

[0019] The size of insert 1 is not particularly limited, but for example, in insert 1A according to the first embodiment, the length of the first side 11A is set to 3 to 20 mm. Also, the height from the first surface 3 to the second surface 5 is set to 2 to 20 mm.

[0020] Furthermore, in an example not limited to the one shown in Figure 1, the insert 1 has through holes 21 that open on the first surface 3 and the second surface 5. The through holes 21 are used as holes into which fasteners are inserted when the insert 11 is mounted on the holder. Examples of fasteners include screws, clamp members, and wedges.

[0021] Furthermore, the through-hole 21 is not limited to the above configuration, and may, for example, open into the third surface 7. In this case, it may penetrate from one surface region of the third surface 7 to another surface region located on the opposite side of that surface.

[0022] The insert 1A according to the first embodiment has a flow channel 22 extending from the first surface 3 to the second surface 5. The flow channel 22 is a passage provided inside the insert 1 to supply coolant to the cutting edge 13 during cutting. There are no particular limitations on the method of forming the flow channel 22. For example, the flow channel 22 may be formed in the insert 1 by drilling, laser processing, or manufacturing with a 3D printer.

[0023] In the example shown in Figure 4, the flow path 22 has an outlet 23 that opens on the first surface 3. The outlet 23 is configured for the discharge of the coolant that has flowed through the flow path 22. In the example shown in Figure 4, when viewed from above, the outlet 23 is elliptical. More specifically, when viewed from above, the ellipse is elongated in the direction in which the first flow path 25 extends, i.e., it is a vertically elongated ellipse. The shape of the outlet 23 is not limited to the above case, and may be circular, horizontally elongated ellipse, or roughly triangular, for example.

[0024] In the insert 1A according to the first embodiment, as shown in the example not limited to Figure 5, the flow path 22 has a first flow path 25 extending from the outlet 23 toward the second surface 5. Also, as shown in the example not limited to Figure 7, in a cross section (hereinafter referred to as the first cross section) that passes through the central axis of the first flow path 25 (hereinafter referred to as the first central axis N1) and is perpendicular to the first surface 3, the width of the first flow path 25 in the direction parallel to the first surface 3 increases as it moves away from the first surface 3. Specifically, in the example not limited to Figure 7, the width W1 of the first flow path 25 in the direction parallel to the first surface 3 increases as it moves away from the first surface 3. This point is the same in the configuration shown in Figure 6.

[0025] Figure 5 shows a VV cross-section obtained by cutting the insert 1 along the VV line shown in Figure 4. The VV cross-section includes the first central axis N1 and is perpendicular to the first surface 3. The first cross-section (VV cross-section) may also include the central axis O of the insert 1. In the example shown in Figure 4, which is not limited to this, the VV line coincides with the bisector of the first corner 9A. Therefore, the first cross-section (VV cross-section) may be a cross-section along the bisector of the first corner 9A. Figure 6 is a diagram showing a modified example of the first flow path 25 in the insert 1A according to the first embodiment, and corresponds to Figure 5.

[0026] Furthermore, in the first cross-section, if the majority of the first surface 3 is not linear and the direction parallel to the first surface 3 cannot be uniquely determined, the direction parallel to the first surface 3 may be defined as the direction perpendicular to the central axis O of the insert 1, which passes through the center of the first surface 3 and the center of the second surface 5. Also, in the insert 1A according to the first embodiment, the first flow channel 25 is formed by laser processing.

[0027] In conventional technology, measures have been taken to efficiently supply coolant to the cutting edge, such as creating a flow path inside the insert to shorten the distance between the cutting edge and the outlet. However, even with such measures, there are limits to increasing the coolant flow velocity (injection pressure), and there is a risk that sufficient coolant may not be supplied to the cutting edge.

[0028] In the insert 1A according to the first embodiment, in the first cross-section, the width of the first flow path 25 in the direction parallel to the first surface 3 increases as it moves away from the first surface 3. That is, because the first flow path 25 has an inverse taper shape, the flow velocity (injection pressure) of the coolant can be increased without being constrained by the insert shape, making it possible to efficiently supply coolant to the cutting edge. Therefore, according to the insert 1A according to the first embodiment, coolant can be efficiently supplied to the cutting edge 13.

[0029] Furthermore, in the insert 1A according to the first embodiment, the first flow channel 25 in a cross-section parallel to the first surface 3 is elliptical, but is not limited to this, and may be circular or approximately triangular, for example. Also, in the insert 1A according to the first embodiment, the first flow channel 25 in a cross-section perpendicular to the first central axis N1 is circular, but is not limited to this, and may be elliptical or approximately triangular, for example.

[0030] In the insert 1A according to the first embodiment, the first central axis N1 approaches the third surface 7 as it approaches the outlet 23. In this case, the coolant flowing through the flow path 22 can be discharged more efficiently in the direction of the cutting edge 13. Specifically, in the first cross-section, as shown in the example not limited to Figure 5, the first central axis N1 approaches the third surface 7 as it approaches the outlet 23. In the example not limited to Figure 5, the first central axis N1 extends upward to the left so that it approaches the third surface 7 shown on the left side of the figure as it approaches the outlet 23 from inside the flow path 22.

[0031] Furthermore, in the example shown in Figure 5, the first central axis N1 is linear in shape and approaches the third surface 7 as it approaches the outlet 23. Alternatively, it can be said that the first central axis N1 approaches the third surface 7 as it approaches the first surface 3. More specifically, as in the example shown in Figure 5, the first central axis N1 approaches the cutting edge 13 as it approaches the outlet 23. Also, the first central axis N1 approaches the first corner 9A as it approaches the outlet 23.

[0032] In the example shown in Figure 5, the first channel 25 has a first channel wall 29 located near the third surface 7, and a second channel wall 31 facing the first channel wall 29. The first channel 25 may also be composed only of the first channel wall 29 and the second channel wall 31. Furthermore, as in the example shown in Figure 5, the first channel wall 29 and the second channel wall 31 are straight in the first cross-section, but are not limited to this, and may be curved, for example.

[0033] In the example shown in Figure 7, the angle between the first channel wall 29 and the first surface 3 is greater than the angle between the second channel wall 31 and the first surface 3. Specifically, as in the example shown in Figure 7, in the first cross-section, if we define the first virtual line as S1 as the line parallel to the first channel wall 29, the second virtual line as S2 as the line parallel to the second channel wall 31, the virtual extension line as T as the line parallel to the first surface 3, the first angle θ1 as the angle between the first virtual line S1 and the virtual extension line T, and the second angle θ2 as the angle between the second virtual line S2 and the virtual extension line T, then θ1 > θ2.

[0034] If the first channel wall 29 is curved, the first virtual line S1 may be a straight line passing through the endpoint on the side of the first surface 3 and the endpoint on the side of the second surface 5 of the first channel wall 29. Similarly, if the second channel wall 31 is curved, a second virtual line S2 may be defined. Furthermore, if the entire first surface 3 in the first cross-section is not straight, the virtual extension line T may be a straight line perpendicular to the central axis O of the insert 1, passing through the center of the first surface 3 and the center of the second surface 5. The first angle θ1 is the angle between the first virtual line S1 and the virtual extension line T that is relatively farther from the third surface 7. The second angle θ2 is the angle between the second virtual line S2 and the virtual extension line T that is relatively farther from the third surface 7. The first angle θ1 and the second angle θ2 may both be acute angles.

[0035] In the above case, the coolant flowing through the flow path 22 can be discharged more efficiently in the direction of the cutting edge 13. Also, as shown in the example without limitation in Figures 5 and 7, in the first cross-section, the second flow path wall 31 is longer than the first flow path wall 29. Specifically, when the length of the first flow path wall 29 is L1 and the length of the second flow path wall 31 is L2, L2 > L1. In this case as well, the coolant flowing through the flow path 22 can be discharged more efficiently in the direction of the cutting edge 13.

[0036] In the insert 1A according to the first embodiment, in the first cross-section, the first flow channel wall 29 and the second flow channel wall 31 each approach the third surface 7 as they approach the outlet 23. In this case, the coolant flowing through the flow channel 22 can be discharged more efficiently in the direction of the cutting edge 13. In the example shown in Figure 5, which is not limited to this, the entirety of the first flow channel wall 29 and the entirety of the second flow channel wall 31 each approach the third surface 7 as they approach the outlet 23.

[0037] In the example shown in Figure 5, at least a portion of the first flow path 25 is located on the side of the second surface 5 rather than the land surface 19. Specifically, as in the example shown in Figure 5, a portion of the first flow path 25 passes through an endpoint on the land surface 19 that is located on the side of the second surface 5, and is located on the side of the second surface 5 than a virtual extension line T' which is a straight line parallel to the first surface 3. In such a case, the length of the first flow path 25 is ensured, so that the coolant flowing through the flow path 22 can be discharged more efficiently in the direction of the cutting edge 13.

[0038] In the insert 1A according to the first embodiment, the flow path 22 further has a second flow path 27 extending from the first flow path 25 toward the second surface 5. In the insert 1A according to the first embodiment, in a cross section (hereinafter referred to as the second cross section) that passes through the central axis of the second flow path 27 (hereinafter referred to as the second central axis N2) and is perpendicular to the first surface 3, the width of the second flow path 27 in the direction perpendicular to the second central axis N2 is constant.

[0039] Specifically, in the example shown in Figures 5 and 7, the width W2 of the second channel 27 in the direction perpendicular to the second central axis N2 is constant from the side of the first surface 3 towards the side of the second surface 5. Note that "constant" does not mean exactly the same; for example, if the maximum and minimum values ​​of the width W2 of the second channel 27 are within ±5% of the average value of the width W2 of the second channel 27, the width W2 of the second channel 27 can be considered constant.

[0040] Furthermore, Figure 5 shows a VV cross-section obtained by cutting insert 1 along the VV line shown in Figure 4. The VV cross-section includes the second central axis N2 and is perpendicular to the first surface 3. The second cross-section (VV cross-section) may also include the central axis O of insert 1.

[0041] In the insert 1A according to the first embodiment, since the first central axis N1 and the second central axis N2 are located on the same cross-section, the cross-section in Figure 5 is both the first cross-section and the second cross-section. However, the invention is not limited to this case, and the first and second cross-sections may be located on different planes. In the insert 1A according to the first embodiment, the second flow path 27 is formed by drilling.

[0042] Furthermore, there are no particular limitations on the shape of the second channel 27 in a cross-section perpendicular to the second central axis N2, but in the insert 1A according to the first embodiment, it is circular. Also, in the insert 1A according to the first embodiment, the second channel 27 is connected to the first channel 25. Specifically, in the example shown in Figure 5, which is not limited, the end of the second channel 27 on the side of the first surface 3 is connected to the end of the first channel 25 on the side of the second surface 5.

[0043] Furthermore, at the above-mentioned end, the inner diameter of the first flow path 25 and the inner diameter of the second flow path 27 are the same, or the inner diameter of the first flow path 25 is smaller than the inner diameter of the second flow path 27. In such cases, the risk of fluid pressure loss is reduced, and the coolant supply efficiency tends to improve.

[0044] In the example shown in Figure 5, the second channel 27 has a third channel wall 33 located near the third surface 7, and a fourth channel wall 35 facing the third channel wall 33. The second channel 27 may also be composed of the third channel wall 33 and the fourth channel wall 35. Also, as in the example shown in Figure 5, the third channel wall 33 and the fourth channel wall 35 are straight in the second cross-section, but are not limited to this, and may be curved, for example. In the example shown in Figure 5, the third channel wall 33 is connected to the first channel wall 29, and the fourth channel wall 35 is connected to the second channel wall 31.

[0045] As shown in the example not limited to Figure 7, in the second cross-section, the second flow channel wall 31 has a first recess 37 in the portion connected to the second flow channel 27. The first recess 37 is located at the end of the second flow channel wall 31 on the side of the second surface 5 and can also be described as being connected to the fourth flow channel wall 35. The end of the second flow channel wall 31 on the side of the second surface 5 is susceptible to impact from the coolant flowing through the second flow channel 27. Therefore, by providing the first recess 37 in the second flow channel wall 31, the above impact can be mitigated and the durability of the first flow channel 25 can be increased.

[0046] As shown in the example not limited to Figure 7, in the first cross-section, the fourth flow channel wall 35 has a second recess 39 in the portion connected to the first flow channel 25. The second recess 39 is located at the end of the fourth flow channel wall 35 on the side of the first surface 3 and can also be described as being connected to the second flow channel wall 31. The coolant flowing through the second flow channel 27 collides with the end of the second flow channel wall 31 on the side of the second surface 5 and is prone to backflow in the direction of coolant flow. Therefore, by providing the second recess 39 in the fourth flow channel wall 35, the backflowing coolant can be received by the second recess 39, and excessive backflow of coolant can be suppressed.

[0047] Furthermore, in the example shown in Figure 7, which is not limited to this, the first recess 37 and the second recess 39 are each V-shaped, but the design is not limited to this, and for example, it may be U-shaped with a concave curved portion at the bottom.

[0048] Furthermore, if the second channel wall 31 and the fourth channel wall 35 each have a first recess 37 and a second recess 39, then the second channel wall 31 and the fourth channel wall 35 are not strictly linear in the first and second cross-sections. However, since the first recess 37 and the second recess 39 are small relative to the entire channel 22, even in the above case, the second channel wall 31 and the fourth channel wall 35 are evaluated as having a linear shape. Specifically, the shapes of the second channel wall 31 and the fourth channel wall 35 as they would be if the first recess 37 and the second recess 39 did not exist are used as the shapes of the second channel wall 31 and the fourth channel wall 35, respectively.

[0049] In the insert 1A according to the first embodiment, the shape of the first channel 25 in the cross section perpendicular to the first surface 3 and the first cross section (hereinafter referred to as the third cross section) is circular. Specifically, as shown in the example without limitation in Figures 8 and 9, if, among any two third cross sections, the cross section on which the first channel 25 is located on the side of the first surface 3 is the VII-VII cross section, and the cross section on which the first channel 25 is located on the side of the second surface 5 is the VIII-VIII cross section, then in either cross section, the shape of the first channel 25 is circular.

[0050] In the insert 1A according to the first embodiment, the VII-VII section and the VIII-VIII section represent sections cut along the VII-VII line and the VIII-VIII line shown in Figures 4 and 5, respectively.

[0051] Here, in the VII-VII section, the first channel 25 is connected to the first surface 3, so the shape of the first virtual circle Q1 centered at the first point P1 shown in Figure 8 is defined as the shape of the first channel 25. Also, in the VIII-VIII section, the first channel 25 is connected to the second channel 27, so the shape of the second virtual circle Q2 centered at the second point P2 shown in Figure 9 is defined as the shape of the first channel 25. Furthermore, since the first central axis N1 passes through the first point P1 and the second point P2, the first point P1 and the second point P2 may be considered as part of the first central axis N1.

[0052] Furthermore, in the insert 1A according to the first embodiment, as the first flow path 25 moves away from the first surface 3, the inner diameter of the first flow path 25 in the third cross-section gradually increases. Specifically, as shown in the example without limitation in Figures 8 and 9, when the inner diameter of the first virtual circle Q1 is R1 and the inner diameter of the second virtual circle Q2 is R2, R2 > R1. In such cases, the coolant supply efficiency tends to improve.

[0053] In the insert 1B according to the second embodiment, it is the same as the insert 1A according to the first embodiment, except for the contents described later (contents related to the flow path 22). Therefore, for contents other than those described later, the description of the first embodiment will be used and a detailed explanation will be omitted. Figures 10 to 14 shown in the insert 1B according to the second embodiment correspond to Figures 3 to 5, Figure 8, and Figure 9 shown in the insert 1A according to the first embodiment, respectively.

[0054] In the insert 1B according to the second embodiment, the shape of the first channel 25 in the third cross-section is elliptical. Specifically, as shown in the example without limitation in Figures 13 and 14, if any two third cross-sections are such that the cross-section where the first channel 25 is located on the side of the first surface 3 is the XII-XII cross-section and the cross-section where the first channel 25 is located on the side of the second surface 5 is the XIII-XIII cross-section, then in either cross-section, the shape of the first channel 25 is elliptical.

[0055] In the insert 1B according to the second embodiment, the XII-XII section and the XIII-XIII section represent sections cut along the XII-XII line and the XIII-XIII line shown in Figures 11 and 12, respectively.

[0056] In the XII-XII section, since the first channel 25 is connected to the first surface 3, the shape of the first channel 25 is defined as the shape of the third virtual ellipse Q3 centered at the third point P3 shown in Figure 13. Also, in the XIII-XIII section, since the first channel 25 is connected to the second channel 27, the shape of the first channel 25 is defined as the shape of the fourth virtual ellipse Q4 centered at the fourth point P4 shown in Figure 14. Furthermore, since the first central axis N1 passes through the third point P3 and the fourth point P4, the third point P3 and the fourth point P4 may be considered as part of the first central axis N1.

[0057] Furthermore, in the insert 1B according to the second embodiment, the width of the first channel 25 in the third cross-section is greater than the length of the first channel 25. Here, width refers to the width in the direction parallel to the first surface 3, and length refers to the width in the direction perpendicular to the first surface 3. Hereafter, unless otherwise specified, width refers to the width of the first channel 25 in the third cross-section, and length refers to the length of the first channel 25 in the third cross-section.

[0058] As shown in the example (not limited to) in Figures 13 and 14, the width W31 of the third virtual ellipse Q3 is greater than the height W32 of the third virtual ellipse Q3, and the width W41 of the fourth virtual ellipse Q4 is greater than the height W42 of the fourth virtual ellipse Q4. In such cases, the coolant can be discharged over a wide area, which tends to improve the coolant supply efficiency.

[0059] Furthermore, in the third cross-section, if the majority of the first surface 3 is not linear and the direction parallel to the first surface 3 and the direction perpendicular to the first surface 3 cannot be uniquely determined, the direction parallel to the first surface 3 may be defined as the direction perpendicular to the central axis O of the insert 1, and the direction perpendicular to the first surface 3 may be defined as the direction parallel to the central axis O of the insert 1.

[0060] In the insert 1B according to the second embodiment, the vertical width of the first flow path 25 gradually increases as it moves away from the first surface 3. Specifically, as shown in the example without limitation in Figures 13 and 14, the vertical width W42 of the fourth virtual ellipse Q4 is larger than the vertical width W32 of the third virtual ellipse Q3. In such cases, the second angle θ2 tends to become smaller, and the coolant supply efficiency tends to improve.

[0061] Furthermore, in the insert 1B according to the second embodiment, the ratio of the vertical width to the horizontal width gradually increases as the first flow path 25 moves away from the first surface 3. Specifically, in the example shown in Figures 13 and 14, W42 / W41 > W32 / W31. In such cases, the coolant supply efficiency tends to improve.

[0062] In the insert 1B according to the second embodiment, the width is constant. Specifically, in the example shown in Figures 13 and 14, W31 = W41. Note that "constant" does not mean strictly the same; for example, the width may be considered constant if the maximum and minimum values ​​of the width are within ±5% of the average value of the width.

[0063] In the insert 1B according to the second embodiment, the outlet 23 is approximately triangular when viewed from above. Specifically, in the example shown in Figures 11 and 12, the width of the outlet 23 in the direction perpendicular to the first central axis N1 increases as it approaches the third surface 7. In the insert 1B according to the second embodiment, since the width of the first flow path 25 in the third cross-section is greater than its height, the apex angle located near the central axis of the insert 1 is greater than 60° in the example shown in Figure 11.

[0064] Examples of materials for insert 1 include cemented carbide, cermet, ceramics, cBN (cubic boron nitride), and PCD (polycrystalline diamond).

[0065] Examples of cemented carbide compositions include WC (tungsten carbide)-Co, WC-TiC (titanium carbide)-Co, and WC-TiC-TaC (tantalum carbide)-Co. Here, WC, TiC, and TaC are hard particles, and Co is the binder phase. Cermets are sintered composite materials formed by combining a metal with a ceramic component. Specifically, cermets include compounds mainly composed of TiC or TiN (titanium nitride). However, the material of insert 1 is not limited to these.

[0066] Furthermore, insert 1 may consist of only one member made of the material exemplified above, or it may consist of multiple members made of the material exemplified above.

[0067] The insert 1 according to this embodiment is composed of a base portion 41 and a cut portion 43, as shown in the example shown in Figure 1, and has a polygonal plate shape overall. The base portion 41 is substantially polygonal plate-shaped and has a cut-out portion at one of its corners. The cut portion 43 is joined to this cut-out portion using brazing material or the like. The joining of the cut portion 43 to the base portion 41 can also be rephrased as the cut portion 43 being attached to the base portion 41. If the insert 1 is composed of only one of the above-mentioned components, the entire insert 1 may be considered as the cut portion 43.

[0068] In the example shown in Figures 3 and 5, the cutting portion 43 includes a part of the first surface 3, a part of the third surface 7, a first corner 9A, a part of the first side 11A, a part of the second side 11B, a cutting edge 13, a land surface 19, and a flow path 22. Regarding the flow path 22, the outlet 23 and the first flow path 25 may be located in the cutting portion 43, and the second flow path 27 may be located in the base portion 41. The cutting portion 43 also has a second surface located on the opposite side of the first surface 3. When the entire insert 1 is the cutting portion 43, the cutting portion 43 has a second surface 5.

[0069] If the material of the cutting portion 43 is a relatively hard material such as cBN and PCD, and the material of the base portion 41 is a cemented carbide, cermet, or ceramic, then the insert 1 can be manufactured inexpensively while having high durability against cutting loads. For example, the base portion 41 is made of cemented carbide and the cutting portion 43 is made of cBN or PCD. The hardness of the base portion 41 and the cutting portion 43 can be evaluated by measuring the Vickers hardness of each part.

[0070] In the case of insert 1 according to this embodiment, where the cutting portion 43 is made of a relatively hard material such as cBN and PCD, it is difficult to perform fine machining on the shape of the cutting portion 43, making it difficult to ensure the efficiency of coolant supply. However, in insert 1 according to this embodiment, by making the first flow path 25 in the reverse taper shape, coolant can be supplied more efficiently to the cutting edge 13 without being restricted by the shape of the insert 1. Therefore, when the cutting portion 43 is made of the above material, the advantages of making the first flow path 25 provided in the cutting portion 43 in the reverse taper shape are more fully utilized.

[0071] Furthermore, the insert 1 may consist only of the base portion 41 and the cutting portion 43 described above, but as an example of a configuration other than the above, it may also include a coating layer (not shown) that covers the surface of the insert 1. The coating layer may cover the entire surface of the insert 1, or it may cover only a part of the surface of the insert 1.

[0072] Examples of materials for the coating layer include aluminum oxide (alumina), as well as titanium carbides, nitrides, oxides, carbonites, nitrogen oxides, carbonitrides, and carbonitrides. The coating layer may contain only one of the above materials, or it may contain multiple materials.

[0073] Furthermore, the coating layer may consist of a single layer or a configuration in which multiple layers are laminated. The material of the coating layer is not limited to these. The coating layer can be positioned on the surface of insert 1, for example, by using chemical vapor deposition (CVD) or physical vapor deposition (PVD).

[0074] Examples of coolants include water-insoluble and water-soluble lubricants. Examples of water-insoluble lubricants include cutting fluids such as oily, inert extreme-pressure, and active extreme-pressure types. Examples of water-soluble lubricants include cutting fluids such as emulsions, solubles, and solutions. The coolant is not limited to a liquid and may also be a gas such as an inert gas. The coolant may be appropriately selected and used depending on the material of the workpiece.

[0075] <Cutting tools> Next, a cutting tool 101 of an embodiment not limited to the present disclosure will be described with reference to the drawings.

[0076] The cutting tool 101 of this embodiment comprises a holder 105 having a pocket 103 located on the tip side, as shown in the example not limited to Figure 15, and an insert 1 according to this embodiment located within the pocket 103. In the cutting tool 101 of this embodiment, the insert 1 is mounted such that at least a portion of the cutting edge 13 protrudes from the tip of the holder 105.

[0077] The holder 105 has a long, slender rod shape. A pocket 103 is provided on the tip side of the holder 105. The pocket 103 is the part into which the insert 1 is inserted and is open to the tip surface of the holder 105. At this time, the pocket 103 is also open to the side of the holder 105, which makes it easy to insert the insert 1. Specifically, the pocket 103 has a seating surface parallel to the bottom surface of the holder 105 and a restraining side surface that is inclined with respect to the seating surface.

[0078] Insert 1 is positioned in pocket 103. In this case, the lower surface of insert 1 may be in direct contact with pocket 103, or a sheet may be placed between insert 1 and pocket 103.

[0079] The insert 1 is mounted such that the cutting edge 13 protrudes outward from the holder 105. In this embodiment, the insert 1 is mounted on the holder 105 by a clamping member 107. That is, the head of the clamping member 107 is pressed against the inner wall of the through hole 21 of the insert 1, thereby restraining the insert 1 in the pocket 103.

[0080] Examples of materials for the holder 105 include steel and cast iron. When the holder 105 is made of steel, its toughness is high.

[0081] In this embodiment, cutting tools used in so-called turning operations are illustrated. Examples of turning operations include internal diameter machining, external diameter machining, and grooving operations. However, the cutting tools are not limited to those used in turning operations. For example, the insert 1 according to the above embodiment may be used as a cutting tool for milling operations.

[0082] <Method for manufacturing machined parts> Next, a method for manufacturing a machined workpiece according to one embodiment not limited to the present disclosure will be described with reference to the drawings.

[0083] The machined workpiece is produced by cutting the workpiece material 201. The method for manufacturing the machined workpiece in this embodiment comprises the following steps: (1) A step of rotating the workpiece 201, (2) A step of bringing a cutting tool 101, as represented in the above embodiment, into contact with a rotating workpiece 201, (3) A step of separating the cutting tool 101 from the workpiece 201, It is equipped with.

[0084] More specifically, first, as shown in the example without limitation in Figure 16, the workpiece 201 is rotated around axis Z, and the cutting tool 101 is brought relatively close to the workpiece 201. Next, as shown in the example without limitation in Figure 17, the cutting edge 13 of the cutting tool 101 is brought into contact with the workpiece 201, and the workpiece 201 is cut. Then, as shown in the example without limitation in Figure 18, the cutting tool 101 is moved relatively away from the workpiece 201.

[0085] In this embodiment, the cutting tool 101 is moved closer to the workpiece 201 by moving it in the Y1 direction while the axis Z is fixed and the workpiece 201 is rotating. Also in Figure 17, the cutting edge 13 is brought into contact with the rotating workpiece 201 and the workpiece 201 is cut by moving it in the Y2 direction. Also in Figure 18, the cutting tool 101 is moved away from the workpiece 201 by moving it in the Y3 direction while the workpiece 201 is rotating.

[0086] In the cutting process in this embodiment, the cutting tool 101 is moved in each step to bring it into contact with the workpiece 201 or to move it away from the workpiece 201. However, the method is not limited to this configuration.

[0087] For example, in step (1), the workpiece 201 may be brought closer to the cutting tool 101. Similarly, in step (3), the workpiece 201 may be moved away from the cutting tool 101. If the cutting process is to be continued, the process of maintaining the rotation of the workpiece 201 and bringing the cutting edge 13 of the insert 1 into contact with different parts of the workpiece 201 can be repeated.

[0088] Examples of materials for the workpiece 201 include carbon steel, alloy steel, stainless steel, cast iron, and non-ferrous metals.

[0089] In one embodiment, [1] the cutting insert has a cutting portion having a first surface having a rake face region, a second surface located opposite the first surface, a third surface located between the first and second surfaces and having a flank surface region, and a flow path extending from the first surface toward the second surface, wherein the flow path has an outlet opening on the first surface and a first flow path extending from the outlet toward the second surface, and in a first cross section passing through the central axis of the first flow path and perpendicular to the first surface, the width of the first flow path in a direction parallel to the first surface increases with distance from the first surface.

[0090] [2] In the cutting insert described in [1] above, the central axis may approach the third surface as it approaches the outlet.

[0091] [3] In the cutting insert described in [1] or [2] above, the first flow channel has a first flow channel wall located near the third surface and a second flow channel wall facing the first flow channel wall, and in the first cross section, the angle between the first flow channel wall and the first surface may be greater than the angle between the second flow channel wall and the first surface.

[0092] [4] In the cutting insert described in [3] above, in the first cross section, the first channel wall and the second channel wall may each approach the third surface as they approach the outlet.

[0093] [5] In any of the cutting inserts described in [1] to [4] above, the cutting portion further has a land surface located between the first surface and the third surface, and at least a portion of the first flow path may be located on the side of the second surface rather than the land surface.

[0094] [6] In any of the cutting inserts described in [1] to [5] above, the flow path further has a second flow path extending from the first flow path toward the second surface, and in a second cross section passing through the central axis of the second flow path and perpendicular to the first surface, the width of the second flow path in a direction parallel to the first surface may be constant from the side of the first surface toward the side of the second surface.

[0095] [7] In the cutting insert described in [6] above, the first flow channel has a first flow channel wall located near the third surface and a second flow channel wall facing the first flow channel wall, and in the second cross section, the second flow channel wall may have a first recess in the portion connected to the second flow channel.

[0096] [8] In the cutting insert described in [6] or [7] above, the first channel has a first channel wall located near the third surface and a second channel wall facing the first channel wall, the second channel has a third channel wall located near the third surface and a fourth channel wall facing the third channel wall, and in the first cross section, the fourth channel wall may have a second recess in the portion connected to the second channel wall.

[0097] [9] In any of the cutting inserts described in [1] to [8] above, the first flow channel may be elliptical in shape in the third cross section perpendicular to the first surface and the first cross section.

[0098]

[10] In the cutting insert described in [9] above, the width of the first channel may be greater than the length of the first channel in the third cross-section.

[0099]

[11] In the cutting insert described in

[10] above, the vertical width may gradually increase as the first flow path moves away from the first surface, and the ratio of the vertical width to the horizontal width may gradually increase.

[0100]

[12] In any of the cutting inserts described in [1] to

[11] above, the cutting portion further comprises a base to which the cutting portion is joined, the base being made of a cemented carbide, and the cutting portion being made of cubic boron nitride or polycrystalline diamond.

[0101]

[13] The cutting tool may have a holder having a pocket located on the tip side, and any of the cutting inserts [1] to

[12] located within the pocket.

[0102]

[14] A method for manufacturing a machined workpiece may include the steps of: rotating a workpiece; bringing the cutting tool described in

[13] into contact with the rotating workpiece; and removing the cutting tool from the workpiece.

[0103] The inventions described in this disclosure have been explained based on the drawings and embodiments. However, the inventions described in this disclosure are not limited to the embodiments described above. That is, the inventions described in this disclosure can be modified in various ways within the scope shown in this disclosure, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the inventions described in this disclosure. In other words, it should be noted that it is easy for those skilled in the art to make various modifications or alterations based on this disclosure. Furthermore, it should be noted that these modifications or alterations are included in the scope of this disclosure. [Explanation of Symbols]

[0104] 1A, 1B... Cutting inserts (inserts) 3...1st side (top side) 5...2nd side (bottom side) 7...Third side (side) 9... Corner 9A...Corner 1 9B... Second corner 9C... Third corner 11...side 11A... First side 11B...Second side 13...cutting blade 13A...First cutting edge 13B...Second cutting edge 13C...First corner cutting edge 15. Rake face area 17. Escape area 19..Land side 21... Through hole 22...flow channel 23...outlet 25...First channel 27...Second channel 29...First channel wall 31...Second channel wall 33. Third channel wall 35...Fourth channel wall 37...First recess 39...Second recess 41...Base 43...Cutting part 101...Cutting tools 103... Pocket 105...Holder 107... Clamp component 201...Work material N1, N2...center axis W1, W2, W31, W32, W41, W42... width O... Insert central axis S1, S2... virtual straight lines T, T'...virtual extension line θ1...first angle θ2···Second angle L1, L2... Length P1~P4...Center of a virtual circle (virtual ellipse) Q1-Q4...Virtual circle (virtual ellipse) R1, R2... Inner diameter Z...axis Y1~Y3...Movement direction

Claims

1. The first surface and, The second surface located on the opposite side of the first surface, A third surface located between the first and second surfaces, It has a cutting section having a flow channel extending from the first surface toward the second surface, The aforementioned flow path is The outlet opening on the first surface, A first flow channel extending from the outlet toward the second surface, It has a second channel extending from the first channel toward the second surface, The first channel is, The first channel wall located near the third surface, The first flow channel wall and the second flow channel wall facing each other are provided, In a first cross-section passing through the central axis of the first flow path and perpendicular to the first surface, The width of the first flow channel in the direction parallel to the first surface increases as it moves away from the first surface. In a second cross-section passing through the central axis of the second flow path and perpendicular to the first surface, The cutting insert has a first recess in the portion of the second channel wall that is connected to the second channel.

2. The first surface has a scooping surface region, The third surface has a relief surface region, The cutting insert according to claim 1, wherein in the second cross-section, the width of the second flow channel in a direction parallel to the first surface is constant from the side of the first surface toward the side of the second surface.

3. The cutting insert according to claim 1, wherein the central axis of the first flow path approaches the third surface as it approaches the outlet.

4. The cutting insert according to claim 1, wherein in the first cross-section, the angle between the first channel wall and the first surface is greater than the angle between the second channel wall and the first surface.

5. The cutting portion further has a land surface located between the first surface and the third surface, The cutting insert according to claim 1, wherein at least a portion of the first flow path is located on the side of the second surface rather than the land surface.

6. The second flow path is A third channel wall located near the aforementioned third surface, It has a fourth channel wall facing the third channel wall, The cutting insert according to claim 1, wherein in the first cross-section, the fourth channel wall has a second recess in the portion connected to the second channel wall.

7. The cutting portion further has a base to which it is joined, The cutting insert according to claim 1, wherein the base is made of a cemented carbide alloy and the cutting portion is made of cubic boron nitride or polycrystalline diamond.

8. The first surface and, The second surface located on the opposite side of the first surface, A third surface located between the first and second surfaces, It has a cutting section having a flow channel extending from the first surface toward the second surface, The aforementioned flow path is The outlet opening on the first surface, A first flow channel extending from the outlet toward the second surface, It has a second channel extending from the first channel toward the second surface, The first channel is, The first channel wall located near the third surface, The first flow channel wall and the second flow channel wall facing each other are provided, In a first cross-section passing through the central axis of the first flow path and perpendicular to the first surface, The width of the first flow channel in the direction parallel to the first surface increases as it moves away from the first surface. The cutting insert has a second recess in the portion of the second channel that is connected to the wall of the second channel.

9. The first surface has a scooping surface region, The third surface has a relief surface region, In a second cross-section passing through the central axis of the second flow path and perpendicular to the first surface, The cutting insert according to claim 8, wherein the width of the second flow channel in a direction parallel to the first surface is constant from the side of the first surface toward the side of the second surface.

10. The cutting portion further has a base to which it is joined, The cutting insert according to claim 8, wherein the base is made of a cemented carbide alloy and the cutting portion is made of cubic boron nitride or polycrystalline diamond.

11. The first surface and, The second surface located on the opposite side of the first surface, A third surface located between the first and second surfaces, It has a cutting section having a flow channel extending from the first surface toward the second surface, The aforementioned flow path is The outlet opening on the first surface, It has a first flow path extending from the outlet toward the second surface, In a first cross-section passing through the central axis of the first flow path and perpendicular to the first surface, The width of the first flow channel in the direction parallel to the first surface increases as it moves away from the first surface. In the third cross-section perpendicular to the first surface and the first cross-section, The first channel is elliptical in shape, The width of the first channel is greater than the length of the first channel. As the first flow path moves away from the first surface, The aforementioned vertical width gradually increases, A cutting insert in which the ratio of the vertical width to the horizontal width gradually increases.

12. The cutting insert according to claim 11, wherein, when the first surface is viewed from the front, the width of the outlet in the direction perpendicular to the central axis of the first flow path increases as it approaches the side of the third surface.

13. A holder having a pocket located on the tip side, A cutting insert according to any one of claims 1 to 12, located within the aforementioned pocket, A cutting tool.

14. The process of rotating the workpiece, A step of bringing the cutting tool described in claim 13 into contact with the rotating workpiece, A method for manufacturing a machined workpiece, comprising the step of separating the cutting tool from the workpiece.

Images