Rotary tools and methods for manufacturing cut works

Abstract

To provide a rotary tool capable of improving the surface roughness of the machined surface. [Solution] A rotary tool, not limited to this disclosure, has a rod-shaped body extending from the front to the rear end along the axis of rotation. The body has a burnishing surface located on the front side, an discharge groove extending from the burnishing surface toward the rear end, and a burnishing blade located at the intersection of the burnishing surface and the discharge groove. The burnishing surface has a first region and a second region located on the outer circumference of the first region. The burnishing angle in the first region is smaller than the burnishing angle in the second region.

Description

Technical Field

[0001] The present disclosure relates to a rotary tool used for cutting a workpiece and a method for manufacturing a machined product. Examples of the rotary tool may include, for example, an end mill. Examples of the end mill may include, for example, a ball end mill, a radius end mill, and a square end mill.

Background Art

[0002] As a rotary tool used when cutting a workpiece, for example, a ball end mill described in Patent Document 1 may be mentioned. In the ball end mill described in Patent Document 1, a part of the ball blade is a vanishing blade, and another part of the ball blade is a normal cutting edge. In Patent Document 1, while ensuring cutting performance by the normal cutting edge, the surface roughness of the machined surface is improved by the vanishing effect in the vanishing blade.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the ball end mill described in Patent Document 1, the relief angle of the relief surface along the vanishing blade is a negative value. If this relief angle is increased (smaller in absolute value), the vanishing effect tends to be small. Also, if the above relief angle is decreased (larger in absolute value), the back force particularly near the rotation axis tends to be large. Therefore, there is a limit to improving the surface roughness of the machined surface under the technical idea described in Patent Document 1.

Means for Solving the Problems

[0005] A rotary tool, not limited to this disclosure, has a rod-shaped body extending from a front end to a rear end along a rotation axis. The body has a burnishing surface located on the front end side, an discharge groove extending from the burnishing surface toward the rear end, and a burnishing blade located at the intersection of the burnishing surface and the discharge groove. In a cross section perpendicular to the rotation axis and perpendicular to the burnishing blade when viewed from the front end side, the angle of inclination of the burnishing surface with respect to a virtual straight line perpendicular to the rotation axis is the burnishing angle. The burnishing surface has a first region and a second region located on the outer circumference side of the first region. The burnishing angle in the first region is smaller than the burnishing angle in the second region. [Effects of the Invention]

[0006] The above-mentioned rotary tool can improve the surface roughness of the machined surface. [Brief explanation of the drawing]

[0007] [Figure 1] This is a perspective view showing one aspect of a rotary tool, not limited to this disclosure. [Figure 2] Figure 1 is a plan view of the rotary tool shown, viewed from the tip side. [Figure 3] This is a magnified view of region III shown in Figure 2. [Figure 4] This is an enlarged view of the same figure as Figure 3. [Figure 5] Figure 2 is a side view of the rotary tool as seen from the V direction. [Figure 6] This is a magnified view of region VI shown in Figure 5. [Figure 7] Figure 6 is a cross-sectional view of section VII of the rotary tool shown. [Figure 8] Figure 7 is a magnified view of region VIII shown in Figure 7. [Figure 9] Figure 2 is a side view of the rotary tool shown, viewed from direction IX. [Figure 10] Figure 9 is a magnified view of region X, with the tip pointed to the left. [Figure 11] It is an enlarged view of the region XI shown in FIG. 10. [Figure 12] It is the same enlarged view as FIG. 3. [Figure 13] It is a cross-sectional view of the XIII cross-section in the rotary tool shown in FIG. 12. [Figure 14] It is a cross-sectional view of the XIV cross-section in the rotary tool shown in FIG. 12. [Figure 15] It is a cross-sectional view of the XV cross-section in the rotary tool shown in FIG. 12. [Figure 16] It is a cross-sectional view of the XVI cross-section in the rotary tool shown in FIG. 12. [Figure 17] It is a cross-sectional view of the XVII cross-section in the rotary tool shown in FIG. 12. [Figure 18] It is a cross-sectional view of the XVIII cross-section in the rotary tool shown in FIG. 12. [Figure 19] It is a cross-sectional view of the XIX cross-section in the rotary tool shown in FIG. 12. [Figure 20] It is a plan view of the rotary tool of one aspect of the present disclosure viewed from the tip side, and it is a figure corresponding to FIG. 4. [Figure 21] It is a side view showing the rotary tool of one aspect of the present disclosure, and it is a figure corresponding to FIG. 6. [Figure 22] It is a cross-sectional view of the XXII cross-section in the rotary tool shown in FIG. 21, and it is a figure corresponding to FIG. 7. [Figure 23] It is an enlarged view of the region XXIII shown in FIG. 22, and it is a figure corresponding to FIG. 8. [Figure 24] It is a side view of the rotary tool shown in FIG. 21, and it is a figure corresponding to FIG. 10. [Figure 25] It is a schematic view showing one step in the method for manufacturing a machined product for one aspect of the present disclosure. [Figure 26] It is a schematic view showing one step in the method for manufacturing a machined product for one aspect of the present disclosure. [Figure 27] It is a schematic view showing one step in the method for manufacturing a machined product for one aspect of the present disclosure. [Figure 28]It is a schematic diagram showing one step in a method for manufacturing a machined product according to a non-limiting aspect of the present disclosure.

Embodiments for Carrying out the Invention

[0008] <Rotary tool> Hereinafter, a rotary tool 1 according to a non-limiting aspect of the present disclosure will be described in detail with reference to the drawings. However, in each of the drawings referred to below, for the sake of convenience of explanation, only the main members necessary for explaining the embodiments are shown in a simplified manner. Therefore, the rotary tool 1 may include any constituent members not shown in each of the drawings referred to. Also, the dimensions of the members in each drawing do not faithfully represent the dimensions of the actual constituent members and the dimensional ratios of each member.

[0009] The rotary tool 1 may have a main body 3 as in a non-limiting example shown in FIGS. 1 to 19. The main body 3 may be in a bar shape extending from the tip 3a toward the rear end 3b along the rotation axis O1. The main body 3 is rotatable around the rotation axis O1. Note that the arrow Y1 in FIG. 1 and the like may indicate the rotation direction of the rotation axis O1, or may indicate the rotation direction of the main body 3 around the rotation axis O1.

[0010] The main body 3 may have a shank portion 5 and a cutting portion 7. The shank portion 5 can function as a portion gripped by a rotating spindle of a machine tool. The shank portion 5 may be designed according to the shape of the spindle in the machine tool.

[0011] The cutting portion 7 may be located on the tip-3a side with respect to the shank portion 5. The cutting portion 7 can come into contact with the workpiece and function as a portion that plays a major role in machining the workpiece.

[0012] The main body 3 is not limited to a specific size. For example, when the outer diameter of the cutting portion 7 is D, the maximum value of D may be set to about 1 to 16 mm. Also, when the length of the cutting portion 7 in the direction along the rotation axis O1 is L, L may be set to about L = 1D to 6D.

[0013] The main body 3 may have a burnishing surface 9, an discharge groove 11, and a burnishing blade 13, as shown in the example (not limited to) in Figures 2 and 3. These parts may be located in the cutting section 7.

[0014] The burnishing surface 9 may be located on the side of the tip 3a. The burnishing surface 9 is a surface that can make surface contact with the workpiece. Unlike relief surfaces, which are generally configured to avoid contact with the workpiece, the burnishing surface 9 can function as a part that smooths the workpiece by making surface contact with it.

[0015] The discharge groove 11 may extend from the burnishing surface 9 toward the rear end 3b, as shown in the example (not limited to) in Figures 5 and 6. The discharge groove 11 can function as a part for discharging chips generated by the burnishing blade 13 to the outside. The discharge groove 11 may extend parallel to the rotation axis O1, or it may extend in a helical shape around the rotation axis O1. In a cross section perpendicular to the rotation axis O1, the discharge groove 11 may have a concave curve shape. The number of discharge grooves 11 may be the same as the number of burnishing blades 13.

[0016] The burnishing blade 13 may be located at the intersection of the burnishing surface 9 and the discharge groove 11. The burnishing blade 13 may be located across the entire intersection, or only in part of the intersection. The burnishing blade 13 can function as the part that cuts the workpiece during the cutting process.

[0017] The burnishing blade 13 may be a single blade or multiple blades. If there are multiple burnishing blades 13, the number of burnishing blades 13 may be, for example, 2 to 6.

[0018] If there are multiple burnishing blades 13, they may be positioned so as to be rotationally symmetric with respect to the rotation axis O1 when viewed from the front side from the tip 3a. For example, as shown in the example not limited to Figure 2, if there are two burnishing blades 13, they may be positioned so as to be rotationally symmetric with respect to the rotation axis O1 by 180° when viewed from the front side from the tip 3a. In this case, the straightness of the rotary tool 1 when cutting the workpiece is high.

[0019] Here, when viewed from the front side from the tip 3a, in a cross section perpendicular to the burnishing blade 13 and parallel to the rotation axis O1, the inclination angle of the burnishing surface 9 with respect to a virtual straight line L1 perpendicular to the rotation axis O1 may be the burnishing angle θ1 (see Figures 12 to 19).

[0020] As shown in the example (not limited to) in Figures 13 to 19, if the burnishing surface 9 tilts toward the tip 3a as it moves away from the burnishing blade 13, the relief angle of the burnishing surface 9 may be evaluated as a negative value. In this case, the burnishing angle θ1 may be the absolute value of the negative relief angle.

[0021] The burnishing surface 9 may have a first region 15 and a second region 17, as shown in the example (not limited to) in Figures 2 and 3. The second region 17 may be located closer to the outer periphery 19 than the first region 15. The burnishing angle θ15 in the first region 15 may be smaller than the burnishing angle θ17 in the second region 17 (see Figures 13, 14, 17-19).

[0022] In the second region 17 of the burnishing surface 9, which is located relatively far from the rotation axis O1, the burnishing angle θ17 is relatively large. Therefore, a stable burnishing effect can be easily obtained in the second region 17. Also, in the first region 15 of the burnishing surface 9, which is located relatively close to the rotation axis O1, the burnishing angle θ15 is relatively small. Therefore, it is easier to avoid the back force becoming too large near the rotation axis O1. As a result, a high burnishing effect can be easily obtained while suppressing the effects of the back force. In addition, a high burnishing effect can be easily obtained regardless of the region of the burnishing blade 13 used for cutting. Therefore, the rotary tool 1 can improve the surface roughness of the machined surface.

[0023] The burnishing angle θ15 in the first region 15 may be constant or vary in the radial direction of the rotation axis O1. For example, if the burnishing angle θ15 in the first region 15 is constant in the radial direction, as shown in the example shown in Figures 13 and 14, the variation in the back force generated in the first region 15 is small. Therefore, the effect of the back force can be further suppressed. In particular, in cutting operations that use only the first region 15 of the burnishing surface 9, the surface roughness of the machined surface tends to be more stable.

[0024] The burnishing angle θ17 in the second region 17 may be constant or vary in the radial direction of the rotation axis O1. For example, if the burnishing angle θ17 in the second region 17 is constant in the radial direction, as shown in the example shown in Figures 17 to 19, the variation in the burnishing effect in the second region 17 is small. Therefore, it is possible to further improve the surface roughness of the machined surface.

[0025] Furthermore, the statement that the burnishing angle θ15 in the first region 15 is constant does not mean that it is strictly constant, but rather that a difference of approximately ±0.2° is tolerable. Similarly, the statement that the burnishing angle θ17 in the second region 17 is constant does not mean that it is strictly constant, but rather that a difference of approximately ±0.5° is tolerable.

[0026] The width of the second region 17 in the radial direction of the rotation axis O1 may be the same as, or different from, the width of the first region 15 in the radial direction.

[0027] For example, the width of the second region 17 in the radial direction may be greater than the width of the first region 15 in the radial direction, as shown in the example not limited to Figure 2. Since the first region 15 is located closer to the axis of rotation O1 than the second region 17, the rotational speed of the first region 15 is slower than that of the second region 17. Therefore, the first region 15 is more likely to be subjected to a relatively large load. However, when the widths of the first region 15 and the second region 17 are configured as described above, it is easier to avoid excessively large loads being applied to the first region 15. Therefore, the durability of the burnishing surface 9 is easily improved. The above configuration is effective when the durability of the burnishing surface 9 is important.

[0028] The burnishing surface 9 may further have a connection region 21, as shown in an example not limited to Figure 3. The connection region 21 may be located between the first region 15 and the second region 17. The connection region 21 may be connected to the first region 15 and the second region 17.

[0029] The burnishing angle θ21 in the connection region 21 may increase as it approaches the second region 17, as shown in the example (not limited to) in Figures 15 and 16. In this case, a sudden change in the burnishing angle θ1 can be avoided. Therefore, chipping of the burnishing blade 13 is less likely to occur.

[0030] The vanishing angle θ1 in each region is not limited to a specific value. For example, the vanishing angle θ15 in the first region 15 may be set to approximately 0.2 to 2°. Similarly, the vanishing angle θ17 in the second region 17 may be set to approximately 6 to 10°. The numerical ranges shown as examples may also represent the absolute value of the relief angle, which may be a negative value.

[0031] The widths of the first region 15 and the second region 17 in the radial direction of the rotation axis O1 may be the same as or different from the width of the connection region 21 in the radial direction. For example, the widths of the first region 15 and the second region 17 in the radial direction may be greater than the width of the connection region 21 in the radial direction, as shown in the example shown in Figure 3. In this case, it is easier to achieve both the suppression of the back force by the first region 15 and the vanishing effect by the second region 17.

[0032] The width of each region in the radial direction of the rotation axis O1 is not limited to a specific value. For example, the width of the first region 15 in the radial direction may be set to approximately 0.1 to 2 mm. Also, the width of the second region 17 in the radial direction may be set to approximately 0.3 to 7 mm.

[0033] The width W15 of the first region 15 in the circumferential direction of the rotation axis O1 may be the same as or different from the width W17 of the second region 17 in the circumferential direction. For example, the width W15 of the first region 15 in the circumferential direction may be smaller than the width W17 of the second region 17 in the circumferential direction, as shown in the example shown in Figure 4. In this case, since the width W15 of the first region 15 is relatively small, the effect of the back force in the first region 15 is easily suppressed. Also, since the width W17 of the second region 17 is relatively large, the vanishing effect in the second region 17 is easily enhanced.

[0034] Furthermore, as shown in the example (not limited to) in Figure 20, the width W15 of the first region 15 in the circumferential direction may be greater than the width W17 of the second region 17 in the circumferential direction. The first region 15 is located closer to the axis of rotation O1 than the second region 17 and rotates at a slower speed than the second region 17. Therefore, the first region 15 is more likely to be subjected to a relatively large load. However, when the widths of the first region 15 and the second region 17 are configured as described above, the durability of the first region 15 tends to improve. For example, this configuration is effective when high durability is required for the burnishing surface 9 when burnishing a hard material such as titanium.

[0035] The width W15 of the first region 15 in the circumferential direction may be constant or vary in the radial direction of the rotation axis O1. For example, if the width W15 of the first region 15 in the circumferential direction is constant in the radial direction, as shown in the example shown in Figure 4, the variation in the effect of suppressing the back force by the first region 15 is reduced. Therefore, it is easier to avoid the concentration of load due to the back force on a part of the first region 15. As a result, the durability of the first region 15 is easily improved.

[0036] Furthermore, the statement that the width W15 of the first region 15 in the circumferential direction is constant in the radial direction of the rotation axis O1 does not mean that it is strictly constant, but rather that a difference of approximately ±0.005 mm is to be allowed. The same applies to the width W17 of the second region 17 in the circumferential direction.

[0037] The width W17 of the second region 17 in the circumferential direction may be constant or vary in the radial direction of the rotation axis O1. For example, if the width W17 of the second region 17 in the circumferential direction is constant in the radial direction, as shown in the example shown in Figure 4, the variation in the burnishing effect due to the second region 17 is reduced. Therefore, it is possible to further improve the surface roughness of the machined surface.

[0038] The width W21 of the connection region 21 in the circumferential direction may increase as it approaches the second region 17, as shown in the example (not limited to) in Figure 4. If the width W21 of the connection region 21 changes discontinuously, chipping may occur in this area, or the machined surface may be damaged by this area. However, when the width W21 of the connection region 21 has the above configuration, chipping is less likely to occur in the connection region 21, and the machined surface is less likely to be damaged. For the same reason, the width W21 of the connection region 21 in the circumferential direction may decrease as it approaches the second region 17, as shown in the example (not limited to) in Figure 20.

[0039] The width of each region in the circumferential direction of the rotation axis O1 is not limited to a specific value. For example, the width W15 of the first region 15 in the circumferential direction may be set to approximately 0.01 to 0.08 mm. Also, the width W17 of the second region 17 in the circumferential direction may be set to approximately 0.025 to 0.1 mm.

[0040] The burnishing blade 13 may have an inner end 13a, as shown in one example, not limited to, Figure 3. The inner end 13a may be located near the axis of rotation O1.

[0041] Furthermore, the main body 3 may have an inner surface 23. The inner surface 23 may be connected to the burnishing surface 9, the discharge groove 11, and the inner end 13a. The inner surface 23 may have a concave curved shape.

[0042] The intersection 25 of the burnishing surface 9 and the inner surface 23 may be formed by a convex curve. If the burnishing surface 9 and the inner surface 23 are simply connected, a ridge line is likely to form at the intersection 25. This ridge line may reduce the surface roughness of the machined surface. However, if the intersection 25 of the burnishing surface 9 and the inner surface 23 is formed by a convex curve, it becomes easier to further improve the surface roughness of the machined surface.

[0043] The discharge groove 11 may have a rake face 27, as shown in Figure 13 and other examples, which are not limited to this. The rake face 27 may be positioned along the burnishing blade 13. The rake face 27 can function as a part where chips flow during cutting.

[0044] The main body 3 may further have a relief surface 29, as shown in the example (not limited to) in Figure 13. The relief surface 29 may extend from the burnishing surface 9 toward the rear in the rotational direction Y1 of the rotation axis O1. The relief surface 29 may be inclined with respect to the burnishing surface 9. The relief surface 29 can function as a part that reduces cutting resistance by avoiding contact with the workpiece. The relief surface 29 may be connected to the burnishing surface 9.

[0045] Examples of materials for the main body 3 include cemented carbide and cermet. Examples of cemented carbide compositions include WC-Co, WC-TiC-Co, and WC-TiC-TaC-Co. Here, WC, TiC, and TaC may be hard particles, and Co may be a bonding phase.

[0046] The cermet may be a sintered composite material in which a metal is combined with a ceramic component. Specifically, examples of cermets include titanium compounds mainly composed of titanium carbide (TiC) or titanium nitride (TiN). However, the above materials are not limited to these materials, and the main body 3 is not limited to these materials.

[0047] The surface of the main body 3 may be coated with a film using chemical vapor deposition (CVD) or physical vapor deposition (PVD). Examples of film compositions include titanium carbide (TiC), titanium nitride (TiN), titanium carbonitride (TiCN), and alumina (Al2O3).

[0048] Next, a rotary tool 1A, which is not limited to this disclosure, will be described with reference to the drawings. In the following, the differences between rotary tool 1A and rotary tool 1 will be mainly described, and detailed explanations of aspects that have the same configuration as rotary tool 1 may be omitted. Therefore, the description of rotary tool 1 may be used to understand the configuration of rotary tool 1A.

[0049] In the rotary tool 1A, the main body 3 may further have a relief surface 31 and an outer peripheral cutting edge 33, as shown in the example (not limited to) in Figures 21 to 24.

[0050] The relief surface 31 may extend from the burnishing surface 9 toward the outer circumference 19 and the rear end 3b, as shown in the example shown in Figure 24 (not limited to this example). The relief surface 31 can function as a part that avoids contact with the workpiece and reduces cutting resistance. The relief surface 29 described above may be referred to as the first relief surface 29, and the relief surface 31 as the second relief surface 31.

[0051] The relief surface 31 may have a positive relief angle θ2. As shown in the example shown in Figure 23, the relief angle θ2 may be the angle at which the tangent L2 of the outer cutting edge 33 intersects the relief surface 31 in a cross section perpendicular to the axis of rotation O1. Furthermore, in the above cross section, if the relief surface 31 is located closer to the axis of rotation O1 than the tangent L2 of the outer cutting edge 33, the relief angle θ2 may be evaluated as having a positive value.

[0052] The outer peripheral cutting edge 33 may extend from the burnishing cutting edge 13 toward the outer circumference 19 and the rear end 3b, as shown in the example shown in Figure 24 (not limited to this example). The outer peripheral cutting edge 33 can function as the part that cuts the workpiece during machining. The rake face 27 described above may be located along the outer peripheral cutting edge 33 in addition to the burnishing cutting edge 13.

[0053] A ridge line 35 may be formed at the boundary between the burnishing surface 9 and the flank surface 31. In this case, the strength near the boundary between the burnishing surface 9 and the flank surface 31 is easily improved, and tool life is easily improved. Also, when a ridge line 35 is formed, the boundary between the burnishing surface 9 and the flank surface 31 is easily visually recognized. Therefore, when using the rotary tool 1, it is easy to intuitively judge even if the cutting conditions such as the depth of cut are set incorrectly.

[0054] The relief angle θ2 of the relief surface 31 is not limited to a specific value. For example, the relief angle θ2 of the relief surface 31 may be set to 0 to 12°.

[0055] <Method for manufacturing machined parts> Next, a method for manufacturing a single-sided machined workpiece 101, not limited to the present disclosure, will be explained with reference to the drawings, using the rotary tool 1 described above as an example.

[0056] The machined workpiece 101 may be produced by machining the workpiece material 103. The method for manufacturing the machined workpiece 101 may include the following steps: (1) A step of rotating the rotary tool 1, which is represented by the above-mentioned non-limited embodiments, (2) The step of bringing the rotating tool 1 into contact with the workpiece 103, (3) A step of separating the rotating tool 1 from the workpiece 103, It may be provided.

[0057] Specifically, first, as shown in the example without limitation in Figure 25, the rotary tool 1 may be rotated around the rotation axis O1 and brought relatively close to the workpiece 103. Next, as shown in the example without limitation in Figures 26 and 27, the burnishing blade 13 of the rotary tool 1 may be brought into contact with the workpiece 103 to cut the workpiece 103. Then, as shown in the example without limitation in Figure 28, the rotary tool 1 may be moved relatively far away from the workpiece 103.

[0058] By following the process described above, it is possible to obtain a machined workpiece 101 with high surface finish accuracy. Specifically, when a rotary tool 1 is used in the manufacturing method of the machined workpiece 101, it is possible to improve the surface roughness of the machined surface, thereby enabling excellent machinability. As a result, it is possible to obtain a machined workpiece 101 with high surface finish accuracy.

[0059] In the example shown in Figures 25 to 28, the workpiece 103 is fixed and the rotary tool 1 is moved during each step, but of course, the system is not limited to this configuration.

[0060] For example, in step (1), the workpiece 103 may be brought closer to the rotating tool 1. Alternatively, in step (3), the workpiece 103 may be moved away from the rotating tool 1. If the cutting process is to continue, the rotating tool 1 may be kept rotating, and the process of bringing the rotating tool 1 into contact with different parts of the workpiece 103 may be repeated.

[0061] Examples of materials for the workpiece 103 include aluminum, carbon steel, alloy steel, stainless steel, cast iron, and non-ferrous metals.

[0062] In the example shown in Figures 25 to 28, a rotary tool 1 is used, but the system is not limited to this configuration. For example, a rotary tool 1A may be used instead of rotary tool 1.

[0063] The above illustrates a method for manufacturing a rotary tool 1, 1A and a workpiece 101, which are not limited to the embodiments described herein. However, it goes without saying that the present disclosure is not limited to the embodiments described above, and any method can be used as long as it does not deviate from the gist of the present disclosure.

[0064] For example, the method for manufacturing the rotary tools 1, 1A and the workpiece 101 may have the following configuration. [1] The rotary tool has a rod-shaped body extending from the front to the rear end along the axis of rotation, the body having a burnishing surface located on the front side, an discharge groove extending from the burnishing surface toward the rear end, and a burnishing blade located at the intersection of the burnishing surface and the discharge groove, the burnishing angle is the angle of inclination of the burnishing surface with respect to a virtual straight line perpendicular to the axis of rotation in a cross section perpendicular to the burnishing blade and parallel to the axis of rotation when viewed from the front side from the front side, the burnishing surface having a first region and a second region located on the outer circumference side of the first region, the burnishing angle in the first region being smaller than the burnishing angle in the second region. [2] The rotary tool described in [1] above may have a burnishing angle in the first region that is constant in the radial direction of the rotation axis. [3] The rotary tool described in [1] or [2] above may have a burnishing angle in the second region that is constant in the radial direction of the rotation axis. [4] Any one of the rotary tools described in [1] to [3] above may have a width in the second region in the radial direction of the rotation axis that is greater than the width in the first region in the radial direction. [5] Any one of the rotary tools described in [1] to [4] above further comprises a connecting region where the burnishing surface is located between the first region and the second region, and the burnishing angle in the connecting region may increase as it approaches the second region. [6] The rotary tool described in [5] above may have widths greater than the width of the connection area in the radial direction of the rotating shaft. [7] Any one of the rotary tools described in [1] to [6] above may have a width in the first region in the circumferential direction of the rotation axis that is smaller than the width in the second region in the circumferential direction. [8] The rotary tool described in [7] above may have a width in the first region in the circumferential direction that is constant in the radial direction of the rotation axis. [9] The rotary tool described in [7] or [8] above may have a width in the second region in the circumferential direction that is constant in the radial direction of the rotation axis.

[10] Any one of the rotary tools described in [7] to [9] above further has a connecting region where the burnishing surface is located between the first region and the second region, and the width of the connecting region in the circumferential direction may increase as it approaches the second region.

[11] Any one of the rotary tools described in [1] to

[10] above, wherein the burnishing blade has an inner end located near the axis of rotation, and the body further has an inner surface connected to the burnishing surface, the discharge groove and the inner end, and the intersection of the burnishing surface and the inner surface may be formed by a convex curve.

[12] Any one of the rotary tools described in [1] to

[11] above further comprises a body having a relief surface extending from the burnishing surface toward the outer circumference and the rear end and having a positive relief angle, and an outer peripheral cutting edge extending from the burnishing blade toward the outer circumference and the rear end, wherein a ridge may be formed at the boundary between the burnishing surface and the relief surface.

[13] A method for manufacturing a machined workpiece may include the steps of rotating one of the rotary tools described in [1] to

[12] above, bringing the rotary tool into contact with the workpiece, and separating the rotary tool from the workpiece. [Explanation of Symbols]

[0065] 1. Rotary tools 3. Main unit 3a...Tip 3b...rear end 5. Shank section 7...Cutting part 9. Burnishing surface 11...Discharge groove 13. Vanishing blade 13a...inner end 15...1st area 17...Second area 19... Perimeter 21...Connection area 23...inner direction 25...interaction 27... Scoop surface 29...Escape Face (First Escape Face) 31...Escape Face (Second Escape Face) 33...Peripheral blade 35...ridgeline 101...Cutting workpiece 103...Work material O1... Rotation axis Y1...Direction of rotation θ1···burning angle θ15 ·· Burning angle in the first region θ17 ·· Burning angle in the second region θ21 ·· Burning angle in the connection region W15··Width of the first region in the circumferential direction of the rotation axis W17··Width of the second region in the circumferential direction of the rotation axis W21 ··Width of the connection area in the circumferential direction of the rotation axis θ2···Relief angle L1... Virtual straight line L2...tangent

Claims

1. It has a rod-shaped body that extends from the tip to the rear end along the axis of rotation, The aforementioned main body is The burnishing surface located on the tip side, A discharge groove extending from the burnishing surface toward the rear end, It has a burnishing blade located at the intersection of the burnishing surface and the discharge groove, When viewed from the front side of the tip, in a cross section perpendicular to the burnishing blade and parallel to the axis of rotation, the angle of inclination of the burnishing surface with respect to a virtual straight line perpendicular to the axis of rotation is the burnishing angle. The aforementioned burnishing surface is The first area and, It has a second region located on the outer periphery of the first region, A rotary tool in which the burnishing angle in the first region is smaller than the burnishing angle in the second region.

2. The rotary tool according to claim 1, wherein the burnishing angle in the first region is constant in the radial direction of the rotation axis.

3. The rotary tool according to claim 1, wherein the burnishing angle in the second region is constant in the radial direction of the rotation axis.

4. The rotary tool according to claim 1, wherein the width of the second region in the radial direction of the rotating shaft is greater than the width of the first region in the radial direction.

5. The burnishing surface further has a connecting region located between the first region and the second region, The rotary tool according to claim 1, wherein the burnishing angle in the connection region increases as it approaches the second region.

6. The rotary tool according to claim 5, wherein the widths of the first region and the second region in the radial direction of the rotating shaft are greater than the width of the connecting region in the radial direction.

7. The rotary tool according to claim 1, wherein the width of the first region in the circumferential direction of the rotating shaft is smaller than the width of the second region in the circumferential direction.

8. The rotary tool according to claim 7, wherein the width of the first region in the circumferential direction is constant in the radial direction of the rotation axis.

9. The rotary tool according to claim 7, wherein the width of the second region in the circumferential direction is constant in the radial direction of the rotation axis.

10. The burnishing surface further has a connecting region located between the first region and the second region, The rotary tool according to claim 7, wherein the width of the connection region in the circumferential direction increases as it approaches the second region.

11. The burnishing blade has an inward end located near the axis of rotation, The main body further has the burnishing surface, the discharge groove, and an inner surface connected to the inner end, The rotary tool according to claim 1, wherein the intersection of the burnishing surface and the inward surface is formed by a convex curve.

12. The aforementioned main body is A relief surface extending from the burnishing surface toward the outer circumference and the rear end, and having a positive relief angle, An outer peripheral blade extending from the burnishing blade toward the outer peripheral side and toward the rear end, It further possesses, The rotary tool according to claim 1, wherein a ridge is formed at the boundary between the burnishing surface and the relief surface.

13. A step of rotating a rotary tool according to any one of claims 1 to 12, The process of bringing the rotating tool into contact with the workpiece, A method for manufacturing a cut workpiece, comprising the step of separating the rotating tool from the workpiece.

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