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

Abstract

A cutting insert according to an undefined embodiment of the present disclosure has a main body part and a cutting part positioned closer to the tip than the main body part. The cutting portion has an upper surface extending from the tip surface toward the main body portion. The upper surface is provided with: a pair of first chip-breaking protrusions that extend from the main body section side toward the tip surface; and a pair of second chip-breaking protrusions extending from the first chip-breaking protrusions toward the tip surface, respectively. Each of the pair of first chip breaking protrusions has a front side surface located on the front end side and having a flat inclined region. The pair of second chip-breaking protrusions are curved-surface-shaped and extend from the front side surfaces of the pair of first chip-breaking protrusions toward the front end surfaces, respectively.

Description

[0001] Cross-reference of related applications

[0002] This application claims priority to Japanese Patent Application No. 2023-185156, filed on October 30, 2023, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] This disclosure relates to a method for manufacturing cutting inserts, cutting tools, and machined parts for cutting workpieces. Examples of cutting operations include turning and milling. Examples of turning operations include internal diameter machining, external diameter machining, grooving, and parting. Background Technology

[0004] As a cutting tool used for machining a workpiece, an example can be found in Japanese Patent Application Publication No. 9-174308 (Patent Document 1). The cutting tool described in Patent Document 1 is a tool for grooving, having a tool holder and a cutting insert (hereinafter also simply referred to as "insert"). The insert described in Patent Document 1 has a pair of chip-breaking protrusions extending from its leading edge. During machining, the chip is deformed by contacting these chip-breaking protrusions, and the speed of chip flow is controlled.

[0005] However, with only a simple pair of chip-breaking protrusions, there is a lack of versatility for cutting conditions and the types of materials being cut. For example, in machining with small feed rates, or in machining soft materials such as aluminum, mild steel, or low-carbon steel, it is difficult to control chip deformation, and the control of chip flow speed based on chip-breaking protrusions, i.e., the effect of chip brake, is limited.

[0006] This disclosure was made in view of the above-mentioned problems, and its purpose is to provide an insert with excellent versatility relative to cutting conditions and the type of material of the workpiece. Summary of the Invention

[0007] The cutting insert disclosed herein is a rod-shaped insert extending along a central axis from a front end to a rear end. The cutting insert has a body portion and a cutting portion located on the front end side of the body portion. The cutting portion has: a front end face located on the front end side; an upper surface extending from the front end face toward the body portion; a first side surface adjacent to the front end face and the upper surface; and a front cutting edge located at the intersection of the front end face and the upper surface.

[0008] The upper surface has: a pair of first chip-breaking protrusions extending from the main body side toward the front end face; and a pair of second chip-breaking protrusions extending from the first chip-breaking protrusions toward the front end face. Each of the first chip-breaking protrusions has a front side face located on the front end side and having a flat, sloping region. The pair of second chip-breaking protrusions are curved and extend from the front side face of the first chip-breaking protrusions toward the front end face. Attached Figure Description

[0009] Figure 1 This is a perspective view of a cutting insert in an undefined manner according to the present disclosure.

[0010] Figure 2 It is Figure 1 The image shown is an enlarged view of region II.

[0011] Figure 3 View from the front Figure 1 A top view of the upper surface of the cutting blade shown.

[0012] Figure 4 It is Figure 3 The area shown is an enlarged view of region IV.

[0013] Figure 5 Viewed from the V direction Figure 3 The side view of the cutting blade shown.

[0014] Figure 6 It is Figure 5 The area shown is a magnified view of region VI.

[0015] Figure 7 Observed from direction VII Figure 3 The top view of the cutting blade shown.

[0016] Figure 8 It is Figure 3 The image shown is an enlarged view of the front end of the cutting blade.

[0017] Figure 9 yes Figure 8 The cutting blade shown is a cross-sectional view of section IX.

[0018] Figure 10 yes Figure 8 The cross-sectional view of the cutting blade shown in the X section.

[0019] Figure 11 yes Figure 8 The cross-sectional view of section XI of the cutting blade shown.

[0020] Figure 12 yes Figure 8 The cross-sectional view of section XII of the cutting insert shown.

[0021] Figure 13 yes Figure 8 The cutting insert shown is a cross-sectional view of section XIII.

[0022] Figure 14 yes Figure 8 The cross-sectional view of section XIV of the cutting insert shown.

[0023] Figure 15 It is Figure 3 The enlarged view shown is of the front end of the cutting insert, and is a cross-sectional view parallel to the central axis and the front cutting edge.

[0024] Figure 16 This is a perspective view of a cutting tool in an undefined manner according to the present disclosure.

[0025] Figure 17 This is a schematic diagram illustrating one step in a method for manufacturing a machined object according to an undefined aspect of this disclosure.

[0026] Figure 18 This is a schematic diagram illustrating one step in a method for manufacturing a machined object according to an undefined aspect of this disclosure.

[0027] Figure 19 This is a schematic diagram illustrating one step in a method for manufacturing a machined object according to an undefined aspect of this disclosure. Detailed Implementation

[0028] <Cutting inserts>

[0029] Hereinafter, a cutting blade 1 (hereinafter also simply referred to as "blade 1") of an unlimited aspect of the present disclosure will be described in detail using the accompanying drawings. However, in the figures referred to below, only the main components necessary for illustrating the embodiments are simplified for ease of explanation. Therefore, the blade 1 can include any constituent components not shown in the referenced figures. In addition, the dimensions of the components in the figures do not faithfully represent the actual dimensions of the constituent components or the dimensional ratios of each component.

[0030] like Figures 1-15 As shown in the undefined example, blade 1 can be a rod-shaped component extending along the central axis O1 from the front end 1a to the rear end 1b. Blade 1 can be prism-shaped. Blade 1 can also be a tetragonal prism-shaped component. It should be noted that the tetragonal prism shape only needs to be approximately tetragonal prism-shaped, and does not need to be a strictly tetragonal prism-shaped component.

[0031] Blade 1 can be like Figure 1 , Figure 3 and Figure 5 As shown in the undefined example, it has a main body 3 and a cutting part 5.

[0032] The main body 3 functions as a part that fixes the blade 1 to the tool holder when it is mounted. The main body 3 can be located at the center of the blade 1 along the central axis O1.

[0033] The cutting part 5 can also be located on the side closer to the front end 1a than the main body part 3. The cutting part 5 can contact the workpiece being cut and can function as a part that plays a major role in the cutting process (e.g., grooving) of the workpiece.

[0034] It should be noted that the blade 1 may also have a cutting portion 7 located on the side further back 1b than the main body 3. In this case, the cutting portion 5 may be referred to as the first cutting portion 5, and the cutting portion 7 as the second cutting portion 7. Furthermore, the second cutting portion 7 may have the same structure as the first cutting portion 5. Therefore, descriptions related to the first cutting portion 5 may also be cited for the purpose of understanding the structure of the second cutting portion 7.

[0035] like Figure 2 As shown in the undefined example, the cutting part 5 may have a front end face 9, an upper surface 11, a first side surface 13, and a front end blade 15.

[0036] The front end face 9 can be located on the front end 1a side. In addition, the upper surface 11 can extend from the front end face 9 toward the main body 3. The first side face 13 can be adjacent to the front end face 9 and the upper surface 11.

[0037] It should be noted that the upper surface 11 is shown for convenience and does not indicate an upward direction. For example, the upper surface 11 does not need to be oriented upward when using the blade 1. This is also the case for other parts that include both upward and downward representations. In addition, the direction orthogonal to the central axis O1 and the direction from the central axis O1 toward the upper surface 11 can be defined as "upward", and the direction from the upper surface 11 toward the central axis O1 can be defined as "downward" to determine the positional relationship in the vertical direction.

[0038] The front cutting edge 15 can be located at the intersection of the front face 9 and the upper surface 11. The front cutting edge 15 can be located entirely at the intersection, or it can be located only at a portion of the intersection. For example, as... Figure 2 As shown in the undefined example, the front cutting edge 15 can also be located entirely at the aforementioned intersection. When using the insert 1 to manufacture a workpiece, the front cutting edge 15 can be used to cut the workpiece. The front cutting edge 15 can generally be referred to as the front cutting edge or the main cutting edge.

[0039] The front cutting edge 15 can be a straight line or a curved shape when viewed from the front or from above. Alternatively, the front cutting edge 15 can be a combination of straight lines and curves when viewed from the front or from above. For example, as... Figure 7 As shown in the undefined example, the front cutting edge 15 can be a straight shape when viewed from the front. Additionally, as... Figure 4 As shown in the undefined example, the front blade 15 can be a straight shape when viewed from above.

[0040] It should be noted that front-end viewing can also be viewed from the front side 1a. Additionally, top-down viewing can also be viewed from the top surface 11. In other words, top-down viewing can also be viewed from the front of the top surface 11.

[0041] Here, as Figure 2 and Figure 4 As shown in the undefined example, the upper surface 11 may have a pair of first chip-breaking protrusions 17 and a pair of second chip-breaking protrusions 19. The pair of first chip-breaking protrusions 17 may extend from the main body portion 3 toward the front end face 9. The pair of second chip-breaking protrusions 19 may extend from the first chip-breaking protrusions 17 toward the front end face 9.

[0042] Each of the pair of first chip-breaking protrusions 17 may have a front side 21. The front side 21 may be located on the front end 1a side. The front side 21 may have a flat, sloping region 23.

[0043] The pair of second chip-breaking protrusions 19 may be curved and extend from the front side 21 of the pair of first chip-breaking protrusions 17 toward the front end face 9.

[0044] In these situations, the insert 1 exhibits excellent versatility in adapting to cutting conditions and the types of materials being cut. For example, in machining soft materials such as aluminum, mild steel, or low-carbon steel, or in machining with small feed rates, the chips tend to elongate, making chip control difficult. In machining such materials, a pair of second chip-breaking protrusions 19 impede the chips, and the chip's direction of travel is easily stabilized. Furthermore, the front surfaces 21 of a pair of first chip-breaking protrusions 17 further impede the chips, and the chips are easily and stably curled.

[0045] In machining hard materials or machining with high feed rates, chip control is difficult because chips are hard to deform. For example, forcibly deforming chips too close to the front face 9 can cause chip clogging. In machining such materials, by making the pair of second chip-breaking protrusions 19 curved, chips can easily cross over them. Therefore, it is possible to prevent chips from curling too close to the front face 9. As a result, chip clogging is less likely to occur.

[0046] Furthermore, the flat, inclined region 23 on the front side 21 facilitates the contact of non-deformable chips with the inclined region 23. This provides resistance to the chips and facilitates their stable curling. Therefore, the insert 1 exhibits excellent versatility for various cutting conditions and types of workpiece materials.

[0047] It should be noted that the front side 21 can be entirely composed of the inclined region 23. The inclined region 23 can also be a flat region that faces upwards as it approaches the main body 3. The flatness of the inclined region 23 does not need to be strictly flat. The inclined region 23 only needs to be generally flat, and can be slightly curved to a degree that is not noticeable when the blade 1 is viewed as a whole, or it can have tiny bumps and depressions. For example, the inclined region 23 can have tiny bumps and depressions of about tens of μm.

[0048] The curved surface shape of the second chip-breaking protrusion 19 can be described as a convex curved surface shape. The second chip-breaking protrusion 19 can be connected to the first chip-breaking protrusion 17.

[0049] A pair of first chip-breaking protrusions 17 can be connected on the side of the main body 3. Additionally, as... Figure 4 As in the undefined example shown, when viewed from above, the pair of first chip-breaking protrusions 17 and the pair of second chip-breaking protrusions 19 can be linearly symmetrical about the vertical bisecting line of the front cutting edge 15. The vertical bisecting line of the front cutting edge 15 can coincide with the central axis O1 when viewed from above.

[0050] The second chip protrusion 19 can be as follows Figure 2 and Figure 4 As shown in the undefined example, it is connected to the front cutting edge 15. In this case, the effect of controlling the direction of chip travel at the second chip-breaking protrusion 19, in other words, guiding the chip, is improved.

[0051] like Figure 10 As in the undefined example shown, in a cross-section orthogonal to the central axis O1, the inclined region 23 can be parallel to the tip edge 15. This cross-section can be orthogonal to the central axis O1 and pass through the inclined region 23. Alternatively, the imaginary line L15 projected onto this cross-section can be considered the tip edge 15. In other words, the imaginary line L15 that causes the tip edge 15 to move parallel to it and intersect the aforementioned cross-section can be considered the tip edge 15. Furthermore, parallelism is not limited to strict parallelism; it can also refer to an inclination that allows for approximately ±5°.

[0052] In the above cross section, when the inclined region 23 is parallel to the front cutting edge 15 (imaginary line L15), the chips tend to flow in a direction orthogonal to the imaginary line L15. Therefore, the chips tend to make stable contact with the inclined region 23, and stable chip discharge can be achieved.

[0053] like Figure 6 and Figure 7 As in the undefined example shown, the inclined region 23 can be located above the second chip-breaking protrusion 19. In this case, the effect of obstructing the chip movement in the inclined region 23 can be improved.

[0054] like Figure 7 As in the undefined example shown, the width W23 of the inclined region 23 along the direction of the front cutting edge 15 can narrow as it faces upwards. In this case, the chips tend to curl stably.

[0055] Inclined region 23 can be as follows Figure 7 As shown in the undefined example, the shape when viewed from the front is triangular. It should be noted that the shape of the inclined region 23 is not limited to the illustrated shape. The shape of the inclined region 23 when viewed from the front can also be trapezoidal, etc.

[0056] Inclined region 23 can also be like Figure 6 As shown in the undefined example, it has a straight shape when viewed from the side of the first side 13. Viewing from the side of the first side 13 is also possible.

[0057] like Figure 2 As in the undefined example shown, the upper surface 11 may also have an inclined surface 25. The inclined surface 25 may be located closer to the main body 3 than the pair of first chip-breaking protrusions 17. The inclined surface 25 may also be a surface that faces upward as it approaches the main body 3.

[0058] like Figure 6 As in the undefined example shown, the tilt angle θ23 of the tilted region 23 can be larger than the tilt angle θ25 of the tilted surface 25. Generally, the tool holder is located behind the blade 1. With the tilt angle θ23 of the tilted region 23 as described above, chips are less likely to travel towards the tool holder, which is located behind the blade 1. Therefore, damage to the tool holder due to chips is easily avoided.

[0059] The tilt angle θ23 of the tilted region 23 and the tilt angle θ25 of the tilted surface 25 can also be tilt angles relative to the central axis O1. When evaluating the tilt angle, an imaginary straight line O1a parallel to the central axis O1 can also be used as a reference. If the tilted region 23 is a straight line when viewed from the side of the first side 13, the tilt angle θ23 can also be evaluated using an imaginary straight line L23 along the tilted region 23. The same applies to the tilted surface 25.

[0060] The tilt angle is not limited to a specific value. For example, the tilt angle θ23 of the tilt region 23 can be set to 30~60°. The tilt angle θ25 of the tilt surface 25 can be set to 25~55°.

[0061] like Figure 2 , Figure 4 as well as Figure 11 As in the undefined example shown, the upper surface 11 may also have a rake face 27. The rake face 27 may be located between a pair of first chip-breaking protrusions 17 and a pair of second chip-breaking protrusions 19. The rake face 27 may also be a face that faces downward away from the tip edge 15. The rake face 27 can function as a part of the chip flow during cutting.

[0062] As in Figure 2 and Figure 4 As in the undefined example shown, the lower end 27a of the rake face 27 can be located between a pair of first chip-breaking protrusions 17. In this case, the chip is unlikely to reach the lower end 27a of the rake face 27, thus easily avoiding excessive obstruction to the chip.

[0063] It should be noted that the lower end 27a can refer to the lowest part of the rake face 27. The lower end 27a of the rake face 27 can be located between the front sides 21 of the pair of first chip breaker protrusions 17. The lower end 27a of the rake face 27 can be located between the inclined regions 23 of the pair of first chip breaker protrusions 17.

[0064] A pair of first chip-breaking protrusions 17 may extend in a direction Y1 where their spacing narrows as they approach the front cutting edge 15. Additionally, a pair of second chip-breaking protrusions 19 may extend in a direction Y2 where their spacing widens as they approach the front cutting edge 15. Figure 15 As shown in the undefined example, these structures can be evaluated with a cross section parallel to the central axis O1 and the front cutting edge 15.

[0065] When the pair of first chip-breaking protrusions 17 extend in a direction Y1 where the distance between them narrows as they approach the front cutting edge 15, it is easy to stably curl the chips traveling between the pair of first chip-breaking protrusions 17. When the pair of second chip-breaking protrusions 19 extend in a direction Y2 where the distance between them widens as they approach the front cutting edge 15, it is easy to avoid excessive obstruction to the chips traveling between the pair of first chip-breaking protrusions 17.

[0066] like Figure 2 and Figure 4As shown in the undefined example, the cutting portion 5 may also have a first transverse cutting edge 29. The first transverse cutting edge 29 may be located at the intersection of the first side surface 13 and the upper surface 11. The first transverse cutting edge 29 may be located entirely at the intersection, or it may be located only at a portion of the intersection. When manufacturing a workpiece using the insert 1, the first transverse cutting edge 29 can be used to improve the smoothness of the inner surface of the groove, or to enlarge the width of the groove in grooving.

[0067] When viewed from the side or top of the first side 13, the first transverse blade 29 can be a straight line or a curved line. Alternatively, when viewed from the side or top of the first side 13, the first transverse blade 29 can be a combination of straight lines and curves. For example, as... Figure 6 As shown in the undefined example, the first transverse blade 29 can be a straight line when viewed from the first side surface 13. Furthermore, when viewed from the first side surface 13, the first transverse blade 29 can be parallel to the central axis O1. However, as stated above, "parallel" in this disclosure is not limited to a strictly parallel structure, and an error (tilt) of approximately ±5° is permissible. For example, even a structure where the first transverse blade 29 is slightly tilted by approximately ±5° relative to the central axis O1 can be considered as having the first transverse blade 29 parallel to the central axis O1. Figure 4 As shown in the undefined example, the first transverse blade 29 can be straight when viewed from above.

[0068] like Figure 6 As shown in the undefined example, when viewed from the side of the first side 13, the inclined region 23 may also be located above the first transverse cutting edge 29. In this case, the chips are less likely to cross the inclined region 23, and the chips tend to curl stably within the inclined region 23.

[0069] The cutting part 5 may also have a first corner cutting edge 31 located at the corner where the front cutting edge 15 intersects with the first transverse cutting edge 29. For example... Figure 4 As shown in the undefined example, the first corner blade 31 can be a convex curve shape when viewed from above.

[0070] It should be noted that, as Figure 2 and Figure 4 As shown in the undefined example, the cutting part 5 may also have: a second side surface 33 located on the opposite side of the first side surface 13 and adjacent to the front end surface 9 and the upper surface 11; a second transverse blade 35 located at the intersection of the second side surface 33 and the upper surface 11; and a second corner blade 37 located at the corner where the front end blade 15 and the second transverse blade 35 intersect.

[0071] The second side edge 33 may have the same structure as the first side edge 13. Additionally, the second transverse cutting edge 35 may have the same structure as the first transverse cutting edge 29. The second corner cutting edge 37 may have the same structure as the first corner cutting edge 31. Therefore, descriptions of the first side edge 13, the first transverse cutting edge 29, and the first corner cutting edge 31 may be cited separately for the purpose of understanding the structures of the second side edge 33, the second transverse cutting edge 35, and the second corner cutting edge 37.

[0072] The blade 1 is not limited to a specific size. For example, the length of the blade 1 along the direction of the central axis O1 can be set to approximately 10 to 40 mm. In addition, the width of the blade 1 in the direction orthogonal to the central axis O1 when viewed from above can be set to approximately 2 to 12 mm. The height of the blade 1 in the direction orthogonal to the central axis O1 when viewed from the front can be set to approximately 2 to 10 mm.

[0073] Materials for the cutting tool 1 can include, for example, cemented carbide and cermet. Compositions of cemented carbide can include, for example, WC-Co, WC-TiC-Co, and WC-TiC-TaC-Co. Here, WC, TiC, and TaC can be hard particles, and Co can be a bonding phase.

[0074] Metal-ceramics can be sintered composite materials incorporating metals into ceramic compositions. Examples of metal-ceramics include titanium compounds with titanium carbide (TiC) or titanium nitride (TiN) as the main components. The material of blade 1 is, of course, not limited to the above compositions.

[0075] The surface of the blade 1 can be coated with a film using chemical vapor deposition (CVD) or physical vapor deposition (PVD). Examples of the components of the coating include titanium carbide (TiC), titanium nitride (TiN), titanium carbonitride (TiCN), and aluminum oxide (Al2O3).

[0076] <Cutting Tools>

[0077] Next, a cutting tool 101 of an unlimited aspect of this disclosure will be described using the accompanying drawings.

[0078] like Figure 16 As shown in the undefined example, the cutting tool 101 may have a tool holder 103 and an insert 1. When the cutting tool 101 has an insert 1, the insert 1 has excellent versatility for cutting conditions and the types of materials of the workpiece, and therefore can achieve high cutting performance.

[0079] The handle 103 can extend from the first end 103a toward the second end 103b. The extending direction of the handle 103 can be consistent with the extending direction of the central axis O1 of the blade 1. Alternatively, the handle 103 can be a rod shape extending from the first end 103a toward the second end 103b. The handle 103 can also be prism-shaped. Alternatively, the handle 103 can be a quadrangular prism shape.

[0080] The tool holder 103 may have a tool groove 105. The tool groove 105 may be located on the side of the first end 103a. The cutting tool 1 can be installed in the tool groove 105.

[0081] The handle 103 may have an upper jaw 107 and a lower jaw 109 located on the first end 103a and in a separated position, or the upper jaw 107 and the lower jaw 109 may form a cutting groove 105.

[0082] The blade 1 can be located within the blade groove 105. When the handle 103 has an upper jaw 107 and a lower jaw 109, the blade 1 can also be held by the upper jaw 107 and the lower jaw 109.

[0083] The blade 1 may be located in the cutter groove 105 such that at least a portion of the part serving as the cutting edge protrudes outward from the first end 103a of the shank 103. For example, the blade 1 may also be located in the cutter groove 105 such that the tip edge 15 protrudes outward from the first end 103a of the shank 103.

[0084] The blade 1 can also be mounted in the blade slot 105 using a screw 111. For example, the blade 1 can also be mounted in the blade slot 105 by inserting the screw 111 into the threaded holes of the upper jaw 107 and the lower jaw 109, thereby fixing the screw 111 in the threaded holes.

[0085] Materials for the handle 103 include, for example, steel and cast iron. When the handle 103 is made of steel, it has high toughness.

[0086] <Methods for Manufacturing Machined Workpieces>

[0087] Next, a method for manufacturing a machined workpiece 201 of an unlimited aspect of this disclosure will be described using the accompanying drawings.

[0088] The workpiece 201 can be manufactured by machining the workpiece 203. The manufacturing method of the workpiece 201 may include the following steps.

[0089] That is, it can include:

[0090] (1) The process of rotating the workpiece 203;

[0091] (2) The process of bringing the rotating workpiece 203 into contact with the cutting tool 101, as represented by the embodiment not specified above; and

[0092] (3) The process of moving the cutting tool 101 away from the workpiece 203.

[0093] Specifically, firstly, such as Figure 17 As shown in the undefined example, the workpiece 203 can be rotated about axis O2, and the cutting tool 101 can be brought relatively close to the workpiece 203. Then, as... Figure 18 As shown in the undefined example, the cutting edge 15 of the cutting tool 101 can be brought into contact with the workpiece 203 to cut the workpiece 203. Furthermore, as... Figure 19 As in the undefined example shown, the cutting tool 101 can also be positioned relatively away from the workpiece 203.

[0094] After the process described above, since the cutting tool 101 has a insert 1 that is highly versatile for cutting conditions and the types of materials of the workpiece 203, it is possible to obtain a machined workpiece 201 with high precision of the finished surface.

[0095] It should be noted that, in Figures 17-19 In one example that is not limited to the one shown, the workpiece 203 to be cut is fixed and the cutting tool 101 is moved in each step, but of course it is not limited to this method.

[0096] For example, in step (1), the workpiece 203 can be brought close to the cutting tool 101. Alternatively, in step (3), the workpiece 203 can be moved away from the cutting tool 101. If the cutting process continues, the workpiece 203 can be kept in a rotating state, and the process of bringing different parts of the cutting tool 101 into contact with the workpiece 203 can be repeated.

[0097] Materials that can be used for the workpiece 203 include, for example, titanium alloys, aluminum, mild steel, carbon steel (high carbon steel and low carbon steel), alloy steel, stainless steel, cast iron and non-ferrous metals.

[0098] The above examples illustrate a method for manufacturing a cutting insert 1, a cutting tool 101, and a workpiece 201 that is not limited to one embodiment of the present disclosure. However, the present disclosure is not limited to the above embodiments, and any method may be used as long as it does not depart from the spirit of the present disclosure.

[0099] For example, the manufacturing method of the cutting insert 1, the cutting tool 101 and the workpiece 201 can be the following structure.

[0100] [1] The cutting insert is a rod-shaped part extending from the front end to the rear end along a central axis, having a main body and a cutting part located on the side of the main body closer to the front end. The cutting part has: a front end face located on the front end side; an upper surface extending from the front end face toward the main body; a first side face adjacent to the front end face and the upper surface; and a front cutting edge located at the intersection of the front end face and the upper surface. The upper surface has: a pair of first chip-breaking protrusions extending from the side of the main body toward the front end face; and a pair of second chip-breaking protrusions extending from the first chip-breaking protrusions toward the front end face. The pair of first chip-breaking protrusions each has a front side face located on the front end side and having a flat inclined region. The pair of second chip-breaking protrusions are curved and extend from the front side face of the pair of first chip-breaking protrusions toward the front end face.

[0101] [2] In the cutting inserts described in [1] above, the second chip-breaking protrusion may also be connected to the front cutting edge.

[0102] [3] In the cutting inserts of [1] or [2] above, the inclined region may be parallel to the front cutting edge in a cross section orthogonal to the central axis.

[0103] [4] In any of the cutting inserts described in [1] to [3] above, the inclined region may be located above the second chip breaking protrusion.

[0104] [5] In any of the cutting blades in [1] to [4] above, the width of the inclined region along the direction of the front cutting edge may narrow as it faces upward.

[0105] [6] In any of the cutting inserts described in any of [1] to [5] above, the upper surface may also have an inclined surface located closer to the main body than the pair of first chip-breaking protrusions and facing upward as it approaches the main body, wherein the inclination angle of the inclined region is greater than the inclination angle of the inclined surface.

[0106] [7] In any of the cutting inserts described in any of [1] to [6] above, the upper surface may also have a rake face located between the pair of first chip-breaking protrusions and the pair of second chip-breaking protrusions, facing downwards away from the front edge, with the lower end of the rake face located between the pair of first chip-breaking protrusions.

[0107] [8] In any of the cutting inserts described in [1] to [7] above, the pair of first chip-breaking protrusions may extend in a direction in which the distance between them narrows as they approach the front cutting edge, and the pair of second chip-breaking protrusions may extend in a direction in which the distance between them widens as they approach the front cutting edge.

[0108] [9] The cutting tool may have: a tool holder that extends from a first end toward a second end and has a tool groove on the side of the first end; and a cutting insert as described in any one of [1] to [8] above, which is located in the tool groove.

[0109]

[10] A method for manufacturing a workpiece may include: a process of rotating the workpiece; a process of bringing the cutting tool described above [9] into contact with the rotating workpiece; and a process of moving the cutting tool away from the workpiece.

[0110] Explanation of reference numerals in the attached figures:

[0111] 1…Cutting insert (blade)

[0112] 1a…Frontend

[0113] 1b…backend

[0114] 3…Main body

[0115] 5…Cutting section (first cutting section)

[0116] 7… Cutting section (second cutting section)

[0117] 9…Front end

[0118] 11… Upper surface

[0119] 13…First profile

[0120] 15…front edge

[0121] 17…First chip breakage protrusion

[0122] 19…Second chip breakage protrusion

[0123] 21…Front Side

[0124] 23…sloping area

[0125] 25… Inclined surface

[0126] 27…Front face

[0127] 27a…lower end

[0128] 29…First Horizontal Blade

[0129] 31…First Corner Blade

[0130] 33…Second side view

[0131] 35…Second Horizontal Blade

[0132] 37…Second Corner Blade

[0133] 101…Cutting tools

[0134] 103…handle

[0135] 103a…First end

[0136] 103b…Second end

[0137] 105…tool groove

[0138] 107…maxilla

[0139] 109… lower jaw

[0140] 111…screw

[0141] 201…workpiece

[0142] 203…workpiece

[0143] O1…Central Axis

[0144] O2… axis.

Claims

1. A cutting insert, which is rod-shaped and extends along a central axis from a front end to a rear end, wherein, The cutting blade has: Main body; as well as The cutting portion is located on the side closer to the front end than the main body portion. The cutting part has: The front end face, which is located on the front end side; The upper surface extends from the front end face toward the main body; The first side surface is adjacent to the front end surface and the upper surface; as well as The front cutting edge is located at the intersection of the front face and the upper surface. The upper surface has: A pair of first chip-breaking protrusions, each extending from the side of the main body toward the front end face; as well as A pair of second chip-breaking protrusions extend from the first chip-breaking protrusion toward the front end face. The pair of first chip-breaking protrusions each have a front side surface, which is located on the front end side and has a flat, sloping area. The pair of second chip-breaking protrusions are curved and extend from the front side of the pair of first chip-breaking protrusions toward the front end face, respectively.

2. The cutting insert according to claim 1, wherein, The second chip-breaking protrusion is connected to the front cutting edge.

3. The cutting insert according to claim 1 or 2, wherein, In a cross section orthogonal to the central axis, the inclined region is parallel to the front cutting edge.

4. The cutting insert according to any one of claims 1 to 3, wherein, The inclined region is located above the second chip-breaking protrusion.

5. The cutting insert according to any one of claims 1 to 4, wherein, The width of the inclined region along the direction of the front edge narrows as it faces upwards.

6. The cutting insert according to any one of claims 1 to 5, wherein, The upper surface also has an inclined surface located closer to the main body than the pair of first chip-breaking protrusions, and oriented upwards as it approaches the main body. The tilt angle of the tilted region is greater than the tilt angle of the tilted surface.

7. The cutting insert according to any one of claims 1 to 6, wherein, The upper surface also has a rake face located between the pair of first chip-breaking protrusions and the pair of second chip-breaking protrusions, facing downwards as it moves away from the front cutting edge. The lower end of the rake face is located between the pair of first chip-breaking protrusions.

8. The cutting insert according to any one of claims 1 to 7, wherein, The pair of first chip-breaking protrusions extend in a direction in which the spacing between them narrows as they approach the tip edge. The pair of second chip-breaking protrusions extend in a direction in which the spacing between them widens as they approach the front cutting edge.

9. A cutting tool, wherein, The cutting tool has: A handle extending from a first end toward a second end, and having a groove on the side of the first end; and The cutting insert according to any one of claims 1 to 8, which is located within the tool groove.

10. 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 9 into contact with the rotating workpiece; and The process of moving the cutting tool away from the workpiece being cut.

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