Cutting insert, cutting tool, and method for manufacturing cut product

Abstract

The purpose of the present invention is to improve the cooling effect of a coolant on a cutting edge, and to improve the durability of a cutting insert and the discharge of cuttings. The cutting insert includes an upper surface having a corner and a first side, a corner side surface, and a corner cutting edge. The upper surface also has a corner land surface extending along the corner cutting edge and inclined upward as it moves away from the corner cutting edge, and a plurality of corner grooves extending from the corner land surface. The plurality of corner grooves have a first corner groove and a second corner groove positioned closer to the first side than the first corner groove, and in a side view of the corner side surface, a lower end of an opening edge of the first corner groove that opens to the corner land surface is positioned above a lower end of an opening edge of the second corner groove that opens to the corner land surface.

Description

Technical Field

[0001] This disclosure relates to cutting inserts, cutting tools, and methods for manufacturing workpieces for cutting workpieces. Background Technology

[0002] As a cutting insert used for machining a workpiece, the cutting insert described in Patent Document 1 can be cited as an example. During machining, a coolant, such as a cooling solvent, is typically sprayed toward the cutting insert to remove chips and cool the cutting insert. To improve the cooling effect of the coolant on the cutting edge, the cutting insert described in Patent Document 1 is provided with grooves.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2014-018891 Summary of the Invention

[0006] The cutting insert disclosed herein has: an upper surface having a corner and a first side connected to the corner; a corner side surface connected to the corner; and a corner cutting edge located at the corner. The upper surface further has: a corner cutting edge surface extending along the corner cutting edge and inclined upwards as it moves away from the corner cutting edge; and a plurality of corner grooves extending from the corner cutting edge surface toward the inner side of the upper surface. The plurality of corner grooves have a first corner groove and a second corner groove located closer to the first side than the first corner groove. In a side view of the corner side surface, the lower end of the first corner groove at the opening edge of the corner cutting edge surface is located above the lower end of the second corner groove at the opening edge of the corner cutting edge surface. Attached Figure Description

[0007] Figure 1 This is a schematic perspective view of a cutting tool according to an embodiment of the present disclosure.

[0008] Figure 2 yes Figure 1 A schematic side view of the cutting tool shown.

[0009] Figure 3 This is a schematic perspective view of a cutting blade according to an embodiment of the present disclosure.

[0010] Figure 4 yes Figure 3 A schematic top view of the cutting blade shown.

[0011] Figure 5 yes Figure 3 The cutting blade shown is from Figure 4A schematic side view viewed from the A1 direction.

[0012] Figure 6 yes Figure 3 The enlarged view of region VI in the figure is a schematic enlarged perspective view of a portion of the cutting blade of an embodiment of the present disclosure.

[0013] Figure 7 yes Figure 4 The enlarged view of region VII in the figure is a schematic enlarged perspective view of a portion of the cutting blade of an embodiment of the present disclosure.

[0014] Figure 8 yes Figure 5 The enlarged view of region VIII in the figure is a schematic enlarged perspective view of a portion of the cutting blade of an embodiment of the present disclosure.

[0015] Figure 9 yes Figure 8 The enlarged view of region IX in the figure is a schematic enlarged perspective view of a portion of the cutting blade of an embodiment of the present disclosure.

[0016] Figure 10 It is along Figure 7 A sectional view of the XX line.

[0017] Figure 11 It is along Figure 7 The sectional views of lines XI-A, XI-B, and XI-C.

[0018] Figure 12 This is a schematic diagram illustrating a method for manufacturing a machined workpiece according to an embodiment of the present disclosure. Detailed Implementation

[0019] Hereinafter, a detailed description of the manufacturing method of the cutting insert, cutting tool, and workpiece according to embodiments of the present disclosure will be provided using the accompanying drawings. However, for ease of explanation, the figures referred to below only show simplified components necessary for illustrating the embodiments. Therefore, the cutting insert of the embodiments of the present disclosure can have any components not shown in the referenced figures. The dimensions of the components in the figures do not faithfully represent the actual dimensions of the components or the dimensional ratios of each component. Furthermore, in this disclosure, parallelism is not limited to strict parallelism, but rather means that an error of approximately ±5 degrees is allowed.

[0020] <Cutting Tools>

[0021] Reference Figure 1 and Figure 2 The cutting tool 1 according to the embodiments of this disclosure will be described. Figure 1 and Figure 2As shown in the example, the cutting tool 1 of the embodiments of this disclosure is used for the workpiece W (refer to...). Figure 12 Turning tools are used in the cutting of workpieces W, including turning, internal machining, grooving, and parting. The cutting tool 1 may have a tool holder 2 mounted on a lathe tool post and a cutting insert 10 held in the tool holder 2.

[0022] The tool holder 2 can be a square bar shape extending from the front end 2a (as the first end) to the rear end 2b (as the second end). The tool holder 2 can also be a bar shape other than a square bar shape, such as a round bar shape. Examples of materials for the tool holder 2 include stainless steel, carbon steel, cast iron, and aluminum alloy. The tool groove 3 for holding the cutting insert 10 can be located on the front end 2a side of the tool holder 2. The length of the tool holder 2 can be set to, for example, 100mm to 400mm.

[0023] A nozzle 4 for spraying coolant, or in other words, spraying cooling medium, toward the cutting insert 10 can be provided on the front end 2a side of the tool holder 2. The coolant may be composed of, for example, a non-water-soluble oil or a water-soluble oil, and can be appropriately selected according to the material of the workpiece W being cut. Examples of non-water-soluble oils include oily, inactive extreme pressure, and active extreme pressure cutting oils. Examples of water-soluble oils include emulsion, water-adjusting, and solvent-based cutting oils. Furthermore, the coolant is not limited to a liquid and may also be a gas such as an inactive gas.

[0024] The cutting insert 10 can be located in the tool groove 3 of the tool holder 2. The cutting insert 10 can also be fixed to the tool groove 3 of the tool holder 2 by means of a clamping member 5. A spray nozzle 6 for spraying coolant toward the cutting insert 10 can be provided on the clamping member 5. Alternatively, the cutting insert 10 can be fixed to the tool groove 3 of the tool holder 2 by means of a fixing screw instead of the clamping member 5.

[0025] <Cutting inserts>

[0026] Reference Figures 3 to 11 The structure of the cutting blade 10 according to the embodiments of this disclosure will be described. For example... Figures 3 to 5 As shown in the example, the cutting insert 10 of the present disclosure may also have a base portion 11 for mounting to the tool groove 3 of the tool holder 2. The base portion 11 may have an upper surface 12 and a bottom surface 13 located on the opposite side of the upper surface 12. The upper surface 12 and the bottom surface 13 may be approximately quadrilateral or other approximately polygonal shapes. In other words, the base portion 11 may also be approximately quadrilateral or other approximately polygonal shapes.

[0027] The base portion 11 may have multiple side surfaces located between the upper surface 12 and the bottom surface 13 of the base portion, any one of which may be a corner side surface 26 described later. The base portion 11 may also have a through hole 14 in its central portion for inserting the aforementioned clamping member 5 or fixing screw. The through hole 14 may also be open on both the upper surface 12 side and the bottom surface 13 side of the base portion.

[0028] The cutting insert 10 of the embodiments of this disclosure may have a cutting portion 20 that contacts the workpiece W to perform cutting. For example... Figure 3 , Figure 4 As shown in the example, the cutting portion 20 may be provided at two opposite corners of the plurality of corners of the base portion 11. Alternatively, the cutting portion 20 may be provided at only one corner of the plurality of corners of the base portion 11. Alternatively, the cutting portion 20 may be provided at each of the plurality of corners of the base portion 11.

[0029] Figure 3 , 4 In the example shown, the cutting portion 20 is located at the intersection of the upper surface 12 and the side surface of the base portion 11, but the structure is not limited to this. For example, the cutting portion 20 may also be located at the intersection of the bottom surface 13 and the side surface of the base portion 11. Alternatively, the cutting portion 20 may be located at both the intersection of the upper surface 12 and the side surface of the base portion 11 and the intersection of the bottom surface 13 and the side surface of the base portion 11.

[0030] Materials used for the cutting part 20 include, for example, hard materials such as cBN (Cubic Boron Nitride) and PCD (PolyCrystalline Diamond). The cutting part 20 can also be bonded to the base part 11 using brazing filler metal. Materials used for the base part 11 include, for example, cemented carbide or cermet.

[0031] Examples of components in cemented carbide include WC-Co, WC-TiC-Co, and WC-TiC-TaC-Co. WC-Co is produced by adding cobalt (Co) powder to tungsten carbide (WC) and then sintering it. WC-TiC-Co is a WC-Co compound with added titanium carbide (TiC). WC-TiC-TaC-Co is a WC-TiC-Co compound with added tantalum carbide (TaC). Furthermore, cermets are sintered composite materials formed by combining metal and ceramic components. Specifically, examples of cermets include those primarily composed of titanium compounds such as titanium carbide (TiC) and titanium nitride (TiN).

[0032] A coating can be applied to the surface of the cutting tool 10 using chemical vapor deposition (CVD) or physical vapor deposition (PVD). Examples of coating materials include titanium carbide (TiC), titanium nitride (TiN), titanium carbonitride (TiCN), or aluminum oxide (Al2O3).

[0033] (Cutting section)

[0034] Reference Figures 6 to 11 The specific structure of the cutting portion 20 of the cutting blade 10 according to the embodiments of this disclosure will be described. For example... Figure 6 , Figure 8 As shown in the example, the cutting portion 20 of the cutting insert 10 may have a cutting portion upper surface (upper surface) 21, which serves as the upper surface of the cutting portion 20. The cutting portion upper surface 21 may function as a rake face for chip flow. The cutting portion upper surface 21 may be connected to the upper surface 12 of the base portion (see reference). Figures 3-5 Together, they form the upper surface of the cutting blade 10.

[0035] The upper surface 21 of the cutting portion may also have a corner 22 and a first side 23 connected to the corner 22. The corner 22 may be curved. The first side 23 may be straight or slightly curved. In addition, the upper surface 21 of the cutting portion may also have a second side 24 connected to the corner 22 on the side opposite to the first side 23.

[0036] The cutting section 20 may also have a corner side 26 connected to the corner 22. The corner side 26 may also function as a flank face. The cutting section 20 may also have a first side 27 connected to the first side 23, and the first side 27 may function as a flank face. The cutting section 20 may also have a second side 28 connected to the second side 24, and the second side 28 may function as a flank face.

[0037] The cutting part 20 may also have a corner cutting edge Ec located at the corner 22. The corner cutting edge Ec may be located at the intersection of the upper surface 21 of the cutting part and the corner side 26. The corner cutting edge Ec may also be located in the entire area or a part of the corner 22. Figure 8 As shown in the example, the corner cutting edge Ec can be a rounded surface that has undergone honing to improve the rigidity of the tool tip.

[0038] The cutting portion 20 may also have a first cutting edge E1 located on the first side 23. The first cutting edge E1 may be located at the intersection of the upper surface 21 of the cutting portion and the first side surface 27. The first cutting edge E1 may also be located over the entire area or a portion of the first side surface 27. The cutting portion 20 may also have a second cutting edge E2 located on the second side 24. The second cutting edge E2 may be located at the intersection of the upper surface 21 of the cutting portion and the second side surface 28. The second cutting edge E2 may also be located over the entire area or a portion of the second side surface 28. Figure 8 As shown in the example, the first cutting edge E1 and the second cutting edge E2 can also be surfaces that have undergone honing to improve the rigidity of the tool tip.

[0039] The upper surface 21 of the cutting part can also have a corner cutting edge surface 30. For example... Figure 8 As shown in the example, the corner cutting edge surface 30 can extend along the corner cutting edge Ec and be inclined upwards as it moves away from the corner cutting edge Ec. That is, the corner cutting edge surface 30 can be a negative cutting edge.

[0040] The corner cutting edge 30 can also be located on the outer edge of the upper surface 21 of the cutting part. The corner cutting edge 30 can also have the function of improving the strength of the corner cutting edge Ec. In a top view, the corner cutting edge 30 can be set as a strip-shaped area with a width of about 0.03 mm to 0.5 mm.

[0041] The upper surface 21 of the cutting section may have a first cutting edge surface 31 and a second cutting edge surface 32. The first cutting edge surface 31 may extend along the first cutting edge E1 and be inclined upward as it moves away from the first cutting edge E1. The second cutting edge surface 32 may extend along the second cutting edge E2 and be inclined upward as it moves away from the second cutting edge E2.

[0042] like Figure 6 , Figure 7 As shown in the example, the upper surface 21 of the cutting portion may also have a plane 33 located inside the upper surface 21 of the cutting portion, relative to the corner cutting edge surface 30 located at the outer edge of the upper surface 21 of the cutting portion, i.e., the upper surface 12 of the base portion (see reference). Figures 3-5 )side.

[0043] (Corner groove)

[0044] like Figure 6 , Figure 7 As shown in the example, the upper surface 21 of the cutting part may also have a plurality of corner grooves 40 extending from the corner cutting edge surface 30 toward the inner side of the upper surface 21 of the cutting part. The plurality of corner grooves 40 may also each function as a coolant storage section for storing coolant. The number of the plurality of corner grooves 40 is not limited to a specific value.

[0045] By designing the upper surface 21 of the cutting part to have multiple corner grooves 40, coolant can be effectively supplied to the corner cutting edge Ec. This improves the cooling effect of the coolant on the corner cutting edge Ec.

[0046] like Figure 7 As shown in the example, multiple corner grooves 40 can also be formed on both sides of the vertical bisecting line L of the corner cutting edge Ec. That is, a first group G1 consisting of multiple corner grooves 40 can be formed on one side of the vertical bisecting line L, and a second group G2 consisting of multiple corner grooves 40 can be formed on the other side of the vertical bisecting line L.

[0047] For ease of explanation, the following description will only cover the multiple corner slots 40 included in the first group G1, omitting the description of the multiple corner slots 40 included in the second group G2. In the case of the multiple corner slots 40 included in the second group G2, the first side 23 can be replaced with the second side 24 in the following description of the multiple corner slots 40 included in the first group G1.

[0048] like Figure 6 , Figure 7 As shown in the example, the multiple corner grooves 40 can also be located away from the corner cutting edge Ec. The multiple corner grooves 40 can also be connected to the corner cutting edge surface 30. The multiple corner grooves 40 can also be connected to the plane 33. When the multiple corner grooves 40 are connected to the plane 33, coolant can easily flow from the plane 33 into the multiple corner grooves 40. As a result, coolant can easily accumulate in the multiple corner grooves 40.

[0049] The multiple corner slots 40 may have a first corner slot 41 to a fourth corner slot 44. Alternatively, the second corner slot 42 may be located closer to the first side 23 than the first corner slot 41, the third corner slot 43 may be located closer to the first side 23 than the second corner slot 42, and the fourth corner slot 44 may be located closer to the first side 23 than the third corner slot 43.

[0050] like Figure 8 , Figure 9 As shown in the example, the opening edge 41a can open at the corner cutting edge surface 30 of the first corner groove 41, and the opening edge 42a can open at the corner cutting edge surface 30 of the second corner groove 42. Alternatively, it can also be as follows... Figure 8 , Figure 9 As shown in the example, when viewed from the side of the corner side 26, the lower end 41aa of the opening edge 41a of the first corner groove 41 is located above the lower end 42aa of the opening edge 42a of the second corner groove 42. When viewed from the side of the corner side 26, the lower the lower end of the opening edge of the corner groove 40 is, the closer the corner groove 40 is to the corner cutting edge Ec.

[0051] The cutting load applied to the corner cutting edge Ec is smaller on the side closer to the first side 23 with a smaller entry angle, and larger closer to the center of the corner cutting edge Ec with a larger entry angle. The center of the corner cutting edge Ec refers to the perpendicular bisecting line L (refer to...). Figure 7 The part that the corner cutting edge Ec passes through. That is, the central side of the corner cutting edge Ec is the area with thicker chips and greater cutting load, while the side closer to the first side 23 is the area with thinner chips and less cutting load.

[0052] Therefore, if the lower ends of the multiple corner grooves 40 are all set to the same low position to ensure cooling effect, sufficient wall thickness cannot be ensured on the central side of the corner cutting edge Ec, resulting in decreased durability. Conversely, if durability is prioritized and the lower ends of the opening edges of the multiple corner grooves 40 are all set to the same high position, the cooling effect will be insufficient.

[0053] In the case of the first corner groove 41 and the second corner groove 42, the first corner groove 41 is located in a region where the cutting load is greater than that of the second corner groove 42. By adopting the above structure, the first corner groove 41, located in a region with a larger cutting load, can be kept away from the corner cutting edge Ec, thus ensuring durability. In addition, by adopting the above structure, for the second corner groove 42, located in a region where the cutting load is smaller than that of the first corner groove 41, a cooling effect can be ensured by being close to the corner cutting edge Ec.

[0054] Furthermore, by adopting the above structure, the velocity difference between the inside and outside of the chip generated at the corner cutting edge Ec increases, which promotes chip curling without increasing resistance, and improves chip discharge performance.

[0055] Specifically, when the upper surface 21 of the cutting section has multiple corner grooves 40, chips are easily introduced into these multiple corner grooves 40. In this case, the multiple corner grooves 40 can play a guiding role, so the flow direction of the chips is easily stabilized.

[0056] Furthermore, by introducing chips into the multiple corner grooves 40, stripes are formed on the chips along the multiple corner grooves 40. By forming stripes in this way, the chips solidify, and thus the behavior of the chips is easily stabilized. Therefore, when a velocity difference is generated between the inside and outside of the chips generated at the aforementioned corner cutting edge Ec, chip curling can be stably promoted.

[0057] That is, by setting the structure as described above, the cooling effect of the coolant on the corner cutting edge Ec can be improved, and the durability of the corner cutting edge Ec, in other words, the cutting insert 10, can be improved, and the chip removal can also be improved.

[0058] exist Figure 9In the text, the lower ends 41aa~44aa of the opening edges 41a~44a of the first corner groove 41~the fourth corner groove 44, and the centers 41ab~44ab of the lower edges of the opening edges 41a~44a are marked. Additionally, below, sometimes the lower end of the opening edge of the corner groove 40 is simply represented as the lower end of the corner groove 40, and the center of the lower edge of the opening edge of the corner groove 40 is simply represented as the center of the corner groove 40.

[0059] like Figure 8 , Figure 9 As shown in the example, the opening edge 43a can open at the corner cutting edge 30 of the third corner groove 43. Alternatively, it can be as follows: Figure 8 , Figure 9 As shown in the example, when viewed from the side of the corner side 26, the lower end 42aa of the opening edge 42a of the second corner groove 42 is located above the lower end 43aa of the opening edge 43a of the third corner groove 43.

[0060] With this structure, when viewed from the side of the corner 26, the lower ends of the multiple corner grooves 40 are positioned progressively downwards, closer to the corner cutting edge Ec, as they approach the first side 23. Therefore, for corner grooves 40 located in areas with high cutting loads, durability can be ensured by positioning them away from the corner cutting edge Ec. Furthermore, for corner grooves 40 located in areas with low cutting loads, the cooling effect of the corner cutting edge Ec can be further improved by positioning them closer to it.

[0061] like Figure 8 , Figure 9 As shown in the example, the opening edge 44a can open at the corner cutting edge 30 of the fourth corner groove 44. In addition, when viewed from the side of the corner side 26, the lower end 43aa of the opening edge 43a of the third corner groove 43 can also be located above the lower end 44aa of the opening edge 44a of the fourth corner groove 44.

[0062] In addition, such as Figure 9 As shown in the example, when viewed from the side of the corner side 26, the lower end 41aa of the opening edge 41a in the first corner groove 41 can also be located closer to the first side 23 than the center 41ab of the lower edge of the opening edge 41a.

[0063] By setting it to such a structure, such as Figure 7As shown in the example, when viewed from above on the upper surface 21 of the cutting section, the lower edge of the opening edge 41a of the first corner groove 41 is positioned such that the side closer to the first side 23 is closer to the corner cutting edge Ec than the side closer to the center of the corner cutting edge Ec. Therefore, the lower edge of the first corner groove 41 is positioned further away from the corner cutting edge Ec in areas of high cutting load and closer to the corner cutting edge Ec in areas of low cutting load, ensuring the durability of the corner cutting edge Ec and improving its cooling effect.

[0064] In this case, it is also possible to... Figure 9 As shown in the example, when viewed from the side of the corner side 26, the lower end of the opening edge of each of the multiple corner grooves 40 at the corner edge surface 30 is located closer to the first side 23 than the center of the lower edge of the opening edge of each of the multiple corner grooves 40. Specifically, when viewed from the side of the corner side 26, the lower end 42aa of the second corner groove 42 may also be located closer to the first side 23 than the center 42ab. In addition, when viewed from the side of the corner side 26, the lower end 43aa of the third corner groove 43 may also be located closer to the first side 23 than the center 43ab. Moreover, when viewed from the side of the corner side 26, the lower end 44aa of the fourth corner groove 44 may also be located closer to the first side 23 than the center 44ab.

[0065] By configuring the structure in this way, in each of the multiple corner grooves 40, the lower edge is positioned further away from the corner cutting edge Ec in areas with higher cutting loads, and closer to the corner cutting edge Ec in areas with lower cutting loads. This further ensures the durability of the corner cutting edge Ec and improves its cooling effect.

[0066] In addition, such as Figure 7 As shown in the example, when viewed from above the upper surface 21 of the cutting portion, the multiple corner grooves 40 can also be located away from the outer edge of the upper surface 21 of the cutting portion. That is, when viewed from above the upper surface 21 of the cutting portion, the multiple corner grooves 40 can also be located away from the corner cutting edge Ec.

[0067] By designing the structure in this way, all the corner grooves 40 are far away from the outer edge of the upper surface 21 of the cutting part. Therefore, compared with the structure in which there are corner grooves that intersect with the outer edge of the upper surface 21 of the cutting part, the durability of the corner cutting edge Ec can be improved.

[0068] Furthermore, in this case, such as Figure 7 As shown in the example, when viewed from above on the upper surface 21 of the cutting portion, the first corner groove 41 may be farther from the outer edge of the upper surface 21 of the cutting portion than the second corner groove 42.

[0069] By designing the structure in this way, the first corner groove, located in the area with a higher cutting load, is farther away from the corner cutting edge Ec, while the second corner groove, located in the area with a lower cutting load, is closer to the corner cutting edge Ec. This ensures the durability of the corner cutting edge Ec and improves its cooling effect.

[0070] In addition, such as Figure 7 As shown in the example, when viewed from above on the upper surface 21 of the cutting section, the directions in which the multiple corner grooves 40 extend can also be parallel to each other.

[0071] By adopting this structure, as described above, the guiding function of the multiple corner grooves 40 can be enhanced, and the flow direction of the chips can be more easily stabilized.

[0072] Moreover, in this case, such as Figure 7 As shown in the example, when viewed from above the upper surface 21 of the cutting part, the plurality of corner grooves 40 can also extend toward the direction of the vertical bisecting line L of the corner cutting edge Ec, respectively, toward the inner side of the upper surface 21 of the cutting part. That is, when viewed from above the upper surface 21 of the cutting part, the first corner groove 41 to the fourth corner groove 44 can also extend toward the direction of the vertical bisecting line L, respectively.

[0073] With this structure, the angle at which the multiple corner grooves 40 intersect the corner cutting edge Ec when stretched in the extending direction of the multiple corner grooves 40 is close to 90°. That is, the flow direction of the chips can be made nearly parallel to the extending direction of the multiple corner grooves 40. Therefore, the guiding effect based on the multiple corner grooves 40 is improved.

[0074] In addition, such as Figure 10 As shown in the example, the first corner groove 41 may also have a bottom 41c and an outer wall portion 41d in a first section D1 that is parallel to the extension direction of the first corner groove 41 and orthogonal to the plane 33. The outer wall portion 41d may also stand up from the bottom 41c and connect the bottom 41c to the corner blade surface 30.

[0075] By designing the structure in this way, even if the wear of the corner cutting edge Ec is aggravated due to the cutting process, the corner cutting edge Ec will have difficulty reaching the first corner groove 41 due to the outer wall portion 41d, thus forming a structure that can withstand wear.

[0076] like Figure 10 As shown in the example, the bottom 41c of the first corner groove 41 in the first section D1 can also be a convex shape that curves upward.

[0077] By introducing chips into the first corner groove 41, the flow direction of the chips is easily stabilized. On the other hand, the first corner groove 41 may wear due to friction, or the flow of chips may stagnate. However, by configuring it in this way, the space in the first corner groove 41 as a coolant storage area can be ensured, and chips are less likely to excessively enter the first corner groove 41. This is because it can reduce the possibility of chips excessively entering the first corner groove 41 from the top of the convex bottom 41c.

[0078] From the viewpoint of efficiently reducing excessive chip entry into the first corner groove 41, the bottom 41c in the first section D1 can also be a convex curve shape that curves upwards.

[0079] In addition, such as Figure 10 As shown in the example, in the first section D1, the outer wall portion 41d can be inclined in such a way that it approaches the outer edge of the upper surface 21 of the cutting portion as it moves away from the bottom 41c. That is, the outer wall portion 41d can be inclined in such a way that it approaches the corner cutting edge Ec as it moves away from the bottom 41c.

[0080] With such a structure, the coolant stored in the first corner groove 41 can be easily supplied to the corner cutting edge Ec.

[0081] In addition, such as Figure 10 As shown in the example, in the first section D1, the first corner groove 41 may also have an inner wall portion 41e located on the opposite side of the outer wall portion 41d and rising from the bottom 41c. The inner wall portion 41e may be formed with an imaginary straight line orthogonal to the plane 33 as the reference axis R, and the angle θ1 formed by the reference axis R and the outer wall portion 41d is larger than the angle θ2 formed by the reference axis R and the inner wall portion 41e.

[0082] With such a structure, the coolant accumulated in the first corner groove 41 is difficult to flow out from the inner wall 41e side, and the coolant is more easily supplied to the corner cutting edge Ec.

[0083] like Figure 11 As shown in the examples of reference numerals 1101 to 1103, in the first corner groove 41, the bottom 41c can also be a concave surface that is recessed downwards in the second section D2 orthogonal to the extending direction of the first corner groove 41.

[0084] The first corner groove 41 may also have a central region as shown by reference numeral 1102, an outer region as shown by reference numeral 1103, and an inner region as shown by reference numeral 1101. In the extending direction of the first corner groove 41, the outer region may be closer to the outer edge of the upper surface 21 of the cutting part than the central region, and the inner region may be farther away from the outer edge of the upper surface 21 of the cutting part than the central region.

[0085] like Figure 11 As shown in the examples with reference numerals 1101 to 1103, in the second section D2, the radius of curvature of the bottom 41c in the central region can be larger than the radius of curvature of the bottom 41c in the outer region and the radius of curvature of the bottom 41c in the inner region, respectively.

[0086] When the chip enters the first corner groove 41, it is easier for the chip to contact the bottom 41c in the central region than the bottom 41c in the outer region and the bottom 41c in the inner region. Thus, the chip in the bottom 41c has a larger radius of curvature in the central region where it is more easily contacted, and the bottom 41c in the central region becomes a gentle curve. Therefore, even when the chip contacts the bottom 41c in the central region, it is difficult for cracks to form in the first corner groove 41.

[0087] Furthermore, when the radius of curvature of the bottom 41c of the second section D2 in the outer region and the radius of curvature of the bottom 41c of the second section D2 in the inner region are relatively small, it is easier to ensure the space in the first corner groove 41 that serves as a coolant storage section.

[0088] In each of the plurality of corner grooves 40, the length of the grooves extending in the direction of extension can be the same or different. In each of the plurality of corner grooves 40, the width of the grooves can be the same or different. In each of the plurality of corner grooves 40, the depth of the grooves can be the same or different. In the plurality of corner grooves 40, the groove spacing between the grooves can be the same or different. In each of the plurality of corner grooves 40, the width of the groove in the length direction can be constant or variable. In the plurality of corner grooves 40, the ends of the grooves on the inner side of the upper surface 21 of the cutting portion can be aligned or misaligned.

[0089] The cross-sectional shape of the multiple corner grooves 40 along the width direction can be V-shaped or rectangular. The length of the multiple corner grooves 40 can be set to, for example, 0.1mm to 3mm. The width of the multiple corner grooves 40 can be set to, for example, 0.03mm to 0.5mm. The depth of the multiple corner grooves 40 can be set to, for example, 0.03mm to 0.5mm.

[0090] <Methods for manufacturing machined parts>

[0091] Reference Figure 12 A method for manufacturing a workpiece according to an embodiment of the present disclosure will be described. Figure 12 This is a schematic diagram illustrating a method for manufacturing a machined workpiece according to an embodiment. For example... Figure 12As shown in the example, the method for manufacturing a workpiece to be cut in the embodiment is a method for manufacturing a workpiece W, i.e., a workpiece M, that has been cut, and includes a first step, a second step, and a third step.

[0092] The first step refers to the step of rotating the workpiece W about its axis S. The second step refers to the step of bringing the cutting insert 10 of the cutting tool 1 into contact with the rotating workpiece W. The third step refers to the step of moving the cutting tool 1 away from the workpiece W. Examples of materials for the workpiece W include stainless steel, carbon steel, alloy steel, cast iron, or non-ferrous metals. Furthermore, the specific details of the method for manufacturing the machined workpiece according to the embodiment are as follows.

[0093] First, the cutting tool 1 is mounted on a tool post (not shown) of the lathe, and the workpiece W to be cut is mounted on a chuck (not shown) of the lathe. Next, as the first operation, as follows... Figure 12 As shown in the example with reference numeral 1201, the chuck is rotated, causing the workpiece W to rotate about its axis S. And, as a second process, as... Figure 12 As shown in the example with reference numeral 1202, the cutting tool 1 is brought close to the workpiece W, and the cutting portion 20 of the cutting insert 10 contacts the outer peripheral surface of the rotating workpiece W and moves downward, thereby cutting the workpiece W. Thus, the workpiece W is machined, and its outer diameter is machined.

[0094] Then, as the third process, such as Figure 12 As shown in the example with reference numeral 1203, the cutting tool 1 is moved radially outward from the circle centered on the axis S, thereby moving the cutting tool 1 away from the workpiece W. Thus, the cutting of the workpiece W is completed, and a machined product M consisting of the workpiece W is produced. The cutting insert 10 possesses excellent cutting ability for the reasons described above, and therefore can produce a machined product M with excellent machining accuracy.

[0095] While continuing the cutting process, the cutting portion 20 of the cutting tool 10 is repeatedly brought into contact with different parts of the workpiece W while the workpiece W is rotated. In the embodiments of this disclosure, the cutting tool 1 is brought close to the workpiece W, but it is sufficient for the cutting tool 1 and the workpiece W to be relatively close; therefore, for example, the workpiece W can also be brought close to the cutting tool 1. This is also done when the cutting tool 1 is moved away from the workpiece W.

[0096] Summary

[0097] The cutting insert of embodiment 1 of this disclosure has: an upper surface having a corner and a first side connected to the corner; a corner side connected to the corner; and a corner cutting edge located at the corner. The upper surface further has: a corner cutting edge surface extending along the corner cutting edge and inclined upwards as it moves away from the corner cutting edge; and a plurality of corner grooves extending from the corner cutting edge surface toward the inner side of the upper surface. The plurality of corner grooves have a first corner groove and a second corner groove located closer to the first side than the first corner groove. When viewed from the side, the lower end of the first corner groove at the opening edge of the corner cutting edge surface is located above the lower end of the second corner groove at the opening edge of the corner cutting edge surface.

[0098] In the cutting blade of Scheme 2 of this disclosure, based on Scheme 1, the plurality of corner grooves further have a third corner groove located closer to the first side than the second corner groove. When viewed from the side of the corner, the lower end of the second corner groove is located above the lower end of the opening edge of the corner cutting edge.

[0099] In embodiment 3 of this disclosure, the cutting blade, based on embodiment 1 or 2, has the plurality of corner grooves located away from the outer edge of the upper surface when viewed from above.

[0100] In embodiment 4 of this disclosure, the cutting blade, based on embodiment 3, has the first corner groove further away from the outer edge of the upper surface than the second corner groove when viewed from above.

[0101] In embodiment 5 of this disclosure, the cutting blade, based on any of embodiments 1 to 4, has, when viewed from the side of the corner side, the lower end of the first corner groove located closer to the first side than the center of the lower edge of the opening edge of the first corner groove.

[0102] In embodiment 6 of this disclosure, the cutting blade, based on embodiment 5, has, when viewed from the side of the corner side, each of the plurality of corner grooves located at the lower end of the opening edge of the corner cutting edge opening closer to the first side than the center of the lower edge of the opening edge of each of the plurality of corner grooves.

[0103] In embodiment 7 of this disclosure, the cutting blade, based on any of embodiments 1 to 6, has the extension directions of the plurality of corner grooves parallel to each other when viewed from above on the upper surface.

[0104] In embodiment 8 of this disclosure, the cutting insert, based on embodiment 7, has multiple corner grooves that, when viewed from above the upper surface, extend toward the direction of the vertical bisecting line of the corner cutting edge, toward the inner side of the upper surface.

[0105] The cutting blade in embodiment 9 of this disclosure is based on any of embodiments 1 to 8, wherein the upper surface has a plane located inside the upper surface than the corner cutting edge surface, and the first corner groove has a bottom and an outer wall portion that rises from the bottom and connects the bottom to the corner cutting edge surface in a first cross section that is parallel to the extension direction of the first corner groove and orthogonal to the plane.

[0106] In embodiment 10 of this disclosure, the cutting blade, based on embodiment 9, has a bottom that is curved upwards in the first cross-section.

[0107] In embodiment 11 of this disclosure, the cutting blade, based on embodiment 9 or 10, has its outer wall portion inclined in the first cross-section in a manner that moves closer to the outer edge of the upper surface as it moves away from the bottom.

[0108] In embodiment 12 of this disclosure, the cutting insert, based on any of embodiments 9 to 11, further comprises, in the first cross section, an inner wall portion located on the opposite side of the outer wall portion and rising from the bottom, the inner wall portion having an imaginary straight line orthogonal to the plane as a reference axis, the angle between the reference axis and the outer wall portion being greater than the angle between the reference axis and the inner wall portion.

[0109] The cutting insert in embodiment 13 of this disclosure, based on any of embodiments 9 to 12, has a bottom that is a concave surface facing downwards in a second cross-section orthogonal to the extension direction of the first corner groove. The first corner groove has, in the extension direction of the first corner groove, a central region; an outer region that is closer to the outer edge of the upper surface than the central region; and an inner region that is farther from the outer edge of the upper surface than the central region. The radius of curvature of the bottom of the second cross-section in the central region is greater than the radius of curvature of the bottom of the second cross-section in the outer region and the radius of curvature of the bottom of the second cross-section in the inner region, respectively.

[0110] The cutting tool in embodiment 14 of this disclosure has: a tool holder that is rod-shaped and extends from a first end toward a second end, having a tool groove at the first end; and a cutting insert of any one of embodiments 1 to 13, which is located in the tool groove.

[0111] The method for manufacturing a workpiece in embodiment 15 of this disclosure includes: a step of rotating a workpiece; a step of bringing the cutting tool of embodiment 14 into contact with the rotating workpiece; and a step of moving the cutting tool away from the workpiece.

[0112] [Additional Items]

[0113] The invention disclosed herein has been described above based on the accompanying drawings and embodiments. However, the invention disclosed herein is not limited to the embodiments described above. That is, the invention disclosed herein 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 within the technical scope of the invention disclosed herein. In other words, please note that those skilled in the art can easily make various modifications or alterations based on this disclosure. In addition, it should be noted that these modifications or alterations are included within the scope of this disclosure.

[0114] Explanation of reference numerals in the attached figures:

[0115] 1. Cutting tools

[0116] 2. Knife handle

[0117] 2a Frontend

[0118] 2B backend

[0119] 3. Tool Groove

[0120] 10 Cutting inserts

[0121] 20 Cutting section

[0122] 21. Upper surface of the cutting section (upper surface)

[0123] 22 Corner

[0124] 26. Corner side

[0125] 30 Corner blade with face

[0126] 33 Plane

[0127] 40 Corner Groove

[0128] 41 First corner groove

[0129] 41aa, 42aa, 43aa (lower end)

[0130] 41c bottom

[0131] 41d outer wall part

[0132] 41a, 42a, 43a Opening edge

[0133] 41c bottom

[0134] 41d outer wall part

[0135] 41e Inner wall portion

[0136] 42 Second corner groove

[0137] 43 Third corner groove

[0138] D1 First Section

[0139] D2 Second Section

[0140] Ec Corner cutting edge

[0141] L perpendicular bisector

[0142] R reference axis

[0143] θ1 Angle between the reference axis and the outer wall portion

[0144] θ2 is the angle between the reference axis and the inner wall.

Claims

1. A cutting insert, wherein, The cutting blade has: The upper surface has a corner and a first side connected to the corner; The side of the corner, which connects to the corner; and A corner cutting edge, located at the corner. The upper surface also has: A corner cutting edge, extending along the corner cutting edge and inclined upwards as it moves away from the corner cutting edge; and Multiple corner grooves extend from the corner cutting edge towards the inside of the upper surface. The plurality of corner slots have a first corner slot and a second corner slot located closer to the first side than the first corner slot. When viewed from the side of the corner, the lower end of the first corner groove at the opening edge of the corner blade surface opening is located above the lower end of the second corner groove at the opening edge of the corner blade surface opening.

2. The cutting insert according to claim 1, wherein, The plurality of corner grooves also includes a third corner groove, which is located closer to the first side than the second corner groove. When viewed from the side of the corner, the lower end of the second corner groove is located above the lower end of the opening edge of the corner blade surface opening of the third corner groove.

3. The cutting insert according to claim 1 or 2, wherein, When viewed from above, the plurality of corner grooves are located away from the outer edge of the upper surface.

4. The cutting insert according to claim 3, wherein, When viewed from above, the first corner groove is farther from the outer edge of the upper surface than the second corner groove.

5. The cutting insert according to any one of claims 1 to 4, wherein, When viewed from the side of the corner, the lower end of the first corner groove is located closer to the first side than the center of the lower edge of the opening edge of the first corner groove.

6. The cutting insert according to claim 5, wherein, When viewed from the side of the corner, the lower end of each of the plurality of corner grooves is located closer to the first side than the center of the lower edge of the opening edge of each of the plurality of corner grooves.

7. The cutting insert according to any one of claims 1 to 6, wherein, When viewed from above on the upper surface, the extension directions of the plurality of corner grooves are parallel to each other.

8. The cutting insert according to claim 7, wherein, When viewed from above, the plurality of corner grooves extend toward the vertical bisecting line of the corner cutting edge, toward the inner side of the upper surface.

9. The cutting insert according to any one of claims 1 to 8, wherein, The upper surface has a plane, and the plane is located inside the upper surface compared to the corner cutting edge surface. The first corner groove has the following characteristics in a first cross-section that is parallel to the extension direction of the first corner groove and orthogonal to the plane: bottom; and The outer wall portion rises from the bottom and connects the bottom to the corner blade surface.

10. The cutting insert according to claim 9, wherein, In the first cross-section, the bottom has a convex shape that curves upwards.

11. The cutting insert according to claim 9 or 10, wherein, In the first cross-section, the outer wall portion is inclined in such a way that it approaches the outer edge of the upper surface as it moves away from the bottom.

12. The cutting insert according to any one of claims 9 to 11, wherein, In the first cross section, The first corner groove also has an inner wall portion, which is located on the opposite side of the outer wall portion and rises from the bottom. The inner wall portion uses an imaginary straight line orthogonal to the plane as a reference axis. The angle between the reference axis and the outer wall portion is greater than the angle between the reference axis and the inner wall portion.

13. The cutting insert according to any one of claims 9 to 12, wherein, The bottom has a concave curved surface that curves downwards in a second cross-section orthogonal to the extension direction of the first corner groove. The first corner groove has the following characteristics in its extending direction: Central region; The outer region, which is closer to the outer edge of the upper surface than the central region; and The inner region is farther from the outer edge of the upper surface than the central region. The radius of curvature of the bottom of the second section in the central region is greater than the radius of curvature of the bottom of the second section in the outer region and the radius of curvature of the bottom of the second section in the inner region.

14. A cutting tool, wherein, The cutting tool has: A knife handle, which is rod-shaped extending from a first end toward a second end, has a groove located at the first end; and The cutting insert according to any one of claims 1 to 13, which is located within the tool groove.

15. A method for manufacturing a workpiece that has been machined by cutting, wherein, The method for manufacturing the workpiece includes: The process of rotating the workpiece; The process of bringing the cutting tool of claim 14 into contact with the rotating workpiece; and The process of moving the cutting tool away from the workpiece being cut.

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