Boring cutter and cutting insert

Abstract

A boring tool (10) has a cutting insert (1), a holder (2), and a pressing member (3). The cutting insert includes a base member (50) and a cutting member (30). The base member includes a first side surface (11), a second side surface (12), a third side surface (13), and a fourth side surface (14). The holder includes a front end surface (74), a rear end surface (75), and an outer peripheral surface (76). The holder has a first hole (71) and a second hole (72) formed therein. The first hole opens at the front end surface. The second hole opens at the outer peripheral surface. The holder includes a stopper (79). A surface constituting the second hole includes a first inner side surface (91) and a second inner side surface (92). The pressing member is in contact with the fourth side surface in a state of being disposed in the first hole. The base member is disposed in the second hole. The first side surface is in contact with the first inner side surface. The second side surface is in contact with the second inner side surface. The third side surface is in contact with the stopper. When viewed in a direction along an extension direction of the second hole, a distance between the first inner side surface and the second inner side surface becomes smaller as it goes from the front end surface toward the rear end surface.

Description

Technical Field

[0001] This invention relates to boring tools and cutting inserts. Background Technology

[0002] Japanese Patent Application Publication No. 2005-34911 (Patent Document 1) discloses a cutting tool having a cutting blade and a blade holder.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2005-34911 Summary of the Invention

[0004] The boring bar of this invention includes a cutting insert, a retainer, and a pressing member. The cutting insert is mounted on the retainer. The pressing member secures the cutting insert to the retainer. The cutting insert includes a base member and a cutting member located on the base member. The base member includes a first side, a second side, a third side, and a fourth side. The second side is inclined relative to the first side. The third side is inclined relative to and connected to both the first and second sides. The fourth side is inclined relative to the first, second, and third sides, separate from and connected to the third side. The retainer includes a front end face, a rear end face, and an outer peripheral face. The outer peripheral face is connected to the front end face. The rear end face is connected to the outer peripheral face from the opposite side of the front end face. The outer peripheral face is connected to both the front end face and the rear end face. A first hole and a second hole are formed in the retainer. The first hole opens on the front end face and extends axially from the front end face. The second hole is connected to the first hole, opens on its outer peripheral surface, and extends radially perpendicular to the axial direction. The retainer includes a stop that covers at least a portion of the second hole. The surface constituting the second hole includes a first inner surface and a second inner surface inclined relative to the first inner surface. The pressing member, when disposed in the first hole, contacts the fourth side surface. The base member is disposed in the second hole. The first side surface contacts the first inner surface. The second side surface contacts the second inner surface. The third side surface contacts the stop. When viewed along the extension direction of the second hole, the distance between the first and second inner surfaces decreases from the front end surface toward the rear end surface.

[0005] The cutting insert of the present invention has a base component and a cutting component disposed on the base component. The base component includes a first side surface, a second side surface, a third side surface, and a fourth side surface. The second side surface is inclined relative to the first side surface. The third side surface is inclined relative to and connected to both the first and second side surfaces. The fourth side surface is inclined relative to the first, second, and third side surfaces, separate from and connected to the third side surface. When viewed in a direction perpendicular to the third side surface, the distance between the first and second side surfaces decreases as one moves away from the fourth side surface. The interface between the base component and the cutting component is provided along a plane parallel to the third side surface. Attached Figure Description

[0006] Figure 1 This is a perspective view showing the structure of the boring bar according to the first embodiment.

[0007] Figure 2 This is a slanted view showing the state of the boring bar according to the first embodiment after disassembly.

[0008] Figure 3 This is a perspective view showing the structure of the cutting insert according to the first embodiment.

[0009] Figure 4 This is a top view schematic diagram showing the structure of the cutting insert according to the first embodiment.

[0010] Figure 5 It is along Figure 4 A cross-sectional view of the V-V line.

[0011] Figure 6 This is a side view schematic diagram showing the structure of the cutting insert according to the first embodiment.

[0012] Figure 7 This is a perspective view showing the structure of the cage according to the first embodiment.

[0013] Figure 8 This is a top view schematic diagram showing the structure of the cage according to the first embodiment.

[0014] Figure 9 It is along Figure 8 A cross-sectional view of the IX-IX line.

[0015] Figure 10 This is a front view showing the structure of the cage according to the first embodiment.

[0016] Figure 11 It is along Figure 10 A cross-sectional view of the XI-XI line.

[0017] Figure 12 This is a top view schematic diagram showing the structure of the boring bar according to the first embodiment.

[0018] Figure 13 It is along Figure 12 A cross-sectional view of line XIII-XIII.

[0019] Figure 14 This is a front view showing the structure of the boring bar according to the first embodiment.

[0020] Figure 15 It is along Figure 14 A cross-sectional view of the XV-XV line.

[0021] Figure 16 This is a perspective view illustrating a method for machining a cylindrical component using a boring bar according to the first embodiment.

[0022] Figure 17 This is a perspective view showing the structure of the cutting insert according to the second embodiment.

[0023] Figure 18 This is a top view schematic diagram showing the structure of the cutting insert according to the second embodiment.

[0024] Figure 19 This is a perspective view showing the structure of the cutting insert according to the third embodiment.

[0025] Figure 20 This is a top view schematic diagram showing the structure of the cutting insert according to the third embodiment.

[0026] Figure 21 This is a perspective view showing the structure of the cutting insert according to the fourth embodiment.

[0027] Figure 22 This is a top view schematic diagram showing the structure of the cutting insert according to the fourth embodiment. Detailed Implementation

[0028] [The problem to be solved by this invention]

[0029] The purpose of this invention is to provide boring tools and cutting inserts that can improve clamping performance through a simple construction.

[0030] [Effects of the Invention]

[0031] According to the present invention, boring tools and cutting inserts with improved clamping performance can be provided through a simple construction.

[0032] [Description of Embodiments of the Invention]

[0033] First, embodiments of the present invention will be described.

[0034] (1) The boring bar 10 of the present invention includes a cutting insert 1, a retainer 2, and a pressing member 3. The cutting insert 1 is mounted on the retainer 2. The pressing member 3 fixes the cutting insert 1 to the retainer 2. The cutting insert 1 includes a base member 50 and a cutting member 30 located on the base member 50. The base member 50 includes a first side 11, a second side 12, a third side 13, and a fourth side 14. The second side 12 is inclined relative to the first side 11. The third side 13 is inclined relative to each of the first side 11 and the second side 12 and is connected to each of the first side 11 and the second side 12. The fourth side 14 is inclined relative to each of the first side 11, the second side 12, and the third side 13, is separate from each of the first side 11 and the second side 12, and is connected to the third side 13. The retainer 2 includes a front end face 74, a rear end face 75, and an outer peripheral face 76. The outer peripheral face 76 is connected to the front end face 74. The rear end face 75 is connected to the outer peripheral face 76 from the opposite side of the front end face 74. A first hole 71 and a second hole 72 are formed in the retainer 2. The first hole 71 opens in the front end face 74 and extends axially from the front end face 74. The second hole 72 is connected to the first hole 71, opens in the outer peripheral face 76, and extends radially perpendicular to the axial direction. The retainer 2 includes a stop 79 that covers at least a portion of the second hole 72. The surface constituting the second hole 72 includes a first inner surface 91 and a second inner surface 92 inclined relative to the first inner surface 91. The pressing member 3, when disposed in the first hole 71, is in contact with the fourth side surface 14. The base member 50 is disposed in the second hole 72. The first side surface 11 is in contact with the first inner surface 91. The second side surface 12 is in contact with the second inner surface 92. The third side surface 13 is in contact with the stop 79. When viewed along the extension direction of the second hole 72, the distance between the first inner surface 91 and the second inner surface 92 decreases as it moves from the front end face 74 toward the rear end face 75.

[0035] (2) According to the boring bar 10 mentioned in (1) above, the cutting component 30 can be made of cubic boron nitride.

[0036] (3) According to the boring bar 10 mentioned in (1) above, the cutting component 30 can be made of sintered diamond.

[0037] (4) According to any one of (1) to (3) above, a coolant supply hole 73 may be provided in the holder 2, which opens in the region between the first inner surface 91 and the second inner surface 92. The direction in which the coolant supply hole 73 extends may be inclined relative to both the axial and radial directions.

[0038] (5) According to any one of (1) to (4) above, the outer diameter of the front end face 74 of the boring tool 10 can be more than 2 mm and less than 10 mm.

[0039] (6) According to any one of (1) to (5) above, the angle formed by the first inner surface 91 and the second inner surface 92 can be more than 70° and less than 110°.

[0040] (7) According to the boring bar 10 mentioned in (1) above, the cutting component 30 can be made of cubic boron nitride. A coolant supply hole 73 can be provided in the holder 2, which opens in the region between the first inner surface 91 and the second inner surface 92. The direction in which the coolant supply hole 73 extends can be inclined relative to both the axial and radial directions. The outer diameter of the front end face 74 can be 2 mm or more and 10 mm or less.

[0041] (8) The processing method of the cylindrical component 100 according to the present invention includes the following steps: A cylindrical component 100 having an outer wall surface 111 and an inner wall surface 112 located inside the outer wall surface 111 is prepared. The cylindrical component 100 is cut using the boring bar 10 described in any one of (1) to (7) above. In the step of cutting the cylindrical component 100, the cutting member 30 contacts the inner wall surface 112.

[0042] (9) The cutting insert 1 according to the present invention has a base member 50 and a cutting member 30 disposed on the base member 50. The base member 50 includes a first side 11, a second side 12, a third side 13, and a fourth side 14. The second side 12 is inclined relative to the first side 11. The third side 13 is inclined relative to each of the first side 11 and the second side 12 and is connected to each of the first side 11 and the second side 12. The fourth side 14 is inclined relative to each of the first side 11, the second side 12, and the third side 13, is separate from each of the first side 11 and the second side 12, and is connected to the third side 13. When viewed in a direction perpendicular to the third side 13, the distance between the first side 11 and the second side 12 decreases as it moves away from the fourth side 14. The interface 60 between the base member 50 and the cutting member 30 is provided along a plane parallel to the third side 13.

[0043] (10) According to the cutting insert 1 mentioned in (9) above, the cutting component 30 can be made of cubic boron nitride.

[0044] (11) According to the cutting insert 1 mentioned in (9) above, the cutting component 30 can be made of sintered diamond.

[0045] (12) In the cutting insert 1 according to any one of (9) to (11) above, the arithmetic mean roughness of each of the first side surface 11, the second side surface 12 and the fourth side surface 14 can be 0.5 μm or more. The arithmetic mean roughness of the third side surface 13 can be less than the arithmetic mean roughness of each of the first side surface 11, the second side surface 12 and the fourth side surface 14.

[0046] [Detailed Description of Embodiments of the Invention]

[0047] Next, the embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following drawings, the same or equivalent parts are labeled with the same reference numerals, and the description will not be repeated.

[0048] (First Embodiment)

[0049] First, a general description of the structure of the boring bar 10 according to the first embodiment will be given.

[0050] Figure 1 This is a perspective view showing the structure of the boring bar 10 according to the first embodiment. Figure 2 This is a perspective view showing the disassembled state of the boring bar 10 according to the first embodiment. The boring bar 10 according to the first embodiment is a turning tool for internal diameter machining. Figure 1 and Figure 2 As shown, the boring bar 10 according to the first embodiment mainly includes a cutting insert 1, a retainer 2, and a pressing member 3. The cutting insert 1 has a cutting edge 34. A first hole 71 and a second hole 72 are provided in the retainer 2. The cutting insert 1 is mounted on the retainer 2. The cutting insert 1 is disposed in the second hole 72. The pressing member 3 fixes the cutting insert 1 to the retainer 2. The pressing member 3 is disposed in the first hole 71.

[0051] Next, the structure of the cutting insert 1 according to the first embodiment will be described.

[0052] Figure 3 This is a perspective view showing the structure of the cutting insert 1 according to the first embodiment. Figure 4 This is a top view schematic diagram showing the structure of the cutting insert 1 according to the first embodiment. (As shown) Figure 3 and Figure 4 As shown, the cutting insert 1 according to the first embodiment has a base component 50 and a cutting component 30. The cutting component 30 is located on the base component 50. The material constituting the base component 50 is different from the material constituting the cutting component 30. The material constituting the base component 50 is, for example, a superhard alloy. The material constituting the cutting component 30 is, for example, cubic boron nitride. The material constituting the cutting component 30 may also be sintered diamond.

[0053] like Figure 3As shown, the base component 50 has a first side 11, a second side 12, a third side 13, a fourth side 14, a fifth side 15, a sixth side 16, a seventh side 17, and a tenth side 20. The second side 12 is inclined relative to the first side 11. The second side 12 is separate from the first side 11. The third side 13 is connected to the first side 11. The third side 13 is inclined relative to the first side 11. The third side 13 is substantially perpendicular to the first side 11. The third side 13 is connected to the second side 12. The third side 13 is inclined relative to the second side 12. The third side 13 is substantially perpendicular to the second side 12.

[0054] The 7th side 17 is located between the 1st side 11 and the 2nd side 12. The 7th side 17 is connected to both the 1st side 11 and the 2nd side 12. The 7th side 17 is inclined relative to both the 1st side 11 and the 2nd side 12. The 7th side 17 is connected to the 3rd side 13. The 7th side 17 is inclined relative to the 3rd side 13. The 7th side 17 is substantially perpendicular to the 3rd side 13.

[0055] The fourth side 14 is located on the opposite side of the seventh side 17. The fourth side 14 may be parallel to the seventh side 17. The fourth side 14 is separate from the seventh side 17. The fourth side 14 is connected to the third side 13. The fourth side 14 is inclined relative to the third side 13. The fourth side 14 is substantially perpendicular to the third side 13. The fourth side 14 is inclined relative to the first side 11. The fourth side 14 is separate from the first side 11. The fourth side 14 is inclined relative to the second side 12. The fourth side 14 is separate from the second side 12.

[0056] The 10th side 20 is located on the opposite side of the 3rd side 13. The 10th side 20 is separate from the 3rd side 13. The 10th side 20 is connected to the 1st side 11, the 2nd side 12, the 4th side 14, the 5th side 15, the 6th side 16, and the 7th side 17. The 10th side 20 has a 1st region 21, a 2nd region 22, and a 3rd region 23. In a direction perpendicular to the 3rd side 13, the 1st region 21 can be separated from the 2nd region 22. The 2nd region 22 is connected to the 3rd region 23. The 2nd region 22 can be parallel to the 3rd side 13. The 2nd region 22 is connected to the 1st side 11. The 2nd region 22 can be separated from the 2nd side 12. The 3rd region 23 is inclined relative to the 2nd region 22. The 3rd region 23 can be connected to the 5th side 15 and the 1st side 11.

[0057] The base component 50 has a protruding component 40. The protruding component 40 is located on the tenth side surface 20. The protruding component 40 is connected to the first region 21. The protruding component 40 can protrude in a direction perpendicular to the third side surface 13. The protruding component 40 has a first top surface 41, a first bottom surface 42, and a first wall surface 43. The first top surface 41 is connected to both the first region 21 and the second region 22. The first top surface 41 is inclined relative to both the first region 21 and the second region 22. The first top surface 41 is substantially perpendicular to the third side surface 13. The first top surface 41 is substantially parallel to both the fifth side surface 15 and the sixth side surface 16.

[0058] The first bottom surface 42 is located on the opposite side of the first top surface 41 in a direction perpendicular to the fifth side surface 15. The first bottom surface 42 is separate from the first top surface 41. The first bottom surface 42 is inclined relative to the first top surface 41. The first wall surface 43 is located between the first top surface 41 and the first bottom surface 42. The first wall surface 43 connects the first top surface 41 and the first bottom surface 42 respectively.

[0059] like Figure 3 and Figure 4 As shown, the cutting component 30 has a second top surface 31, a second bottom surface 32, a second wall surface 33, and a cutting edge 34. The second top surface 31 is connected to the first top surface 41. The second top surface 31 is disposed along the first top surface 41. The second top surface 31 functions, for example, as a forward-inclined surface. The second bottom surface 32 is connected to the first bottom surface 42. The second bottom surface 32 is disposed along the first bottom surface 42. The second bottom surface 32 is located on the opposite side of the second top surface 31. The second bottom surface 32 is inclined relative to the second top surface 31. The second wall surface 33 is connected to the first wall surface 43. The second wall surface 33 is an outwardly convex curved surface. The second wall surface 33 functions, for example, as a back clearance surface. The edge between the second wall surface 33 and the second top surface 31 forms the cutting edge 34.

[0060] Figure 5 It is along Figure 4 A cross-sectional view of the V-V line. Figure 5 The cross-section shown is parallel to the third side surface 13. (As shown) Figure 5 As shown, the base component 50 also has an eighth side surface 18 and a ninth side surface 19. The eighth side surface 18 is located between the fourth side surface 14 and the fifth side surface 15. The eighth side surface 18 is connected to both the fourth side surface 14 and the fifth side surface 15. The eighth side surface 18 is an outwardly convex curved surface. The ninth side surface 19 is located between the fourth side surface 14 and the sixth side surface 16. The ninth side surface 19 is connected to both the fourth side surface 14 and the sixth side surface 16. The ninth side surface 19 is an outwardly convex curved surface.

[0061] Side 5 15 is located on the opposite side of side 6 16. Side 5 15 may be substantially parallel to side 6 16. Side 5 15 is located between side 8 18 and side 11. Side 5 15 is connected to side 8 18 and side 11 respectively. Side 5 15 is inclined relative to side 11, side 2 12, side 4 14 and side 7 17 respectively. Side 6 16 is located between side 9 19 and side 2 12. Side 6 16 is connected to side 9 19 and side 2 12 respectively. Side 6 16 is inclined relative to side 11, side 2 12, side 4 14 and side 7 17 respectively.

[0062] like Figure 5 As shown, when viewed along a direction perpendicular to the third side 13, the distance between the first side 11 and the second side 12 decreases as the distance moves away from the fourth side 14. The distance between the first side 11 and the second side 12 is the distance in a direction parallel to the fourth side 14. The distance between the first side 11 and the second side 12 decreases monotonically as the distance moves from the fourth side 14 toward the seventh side 17. The first side 11 and the second side 12 are each planar. The fourth side 14, the fifth side 15, the sixth side 16, and the seventh side 17 are each planar.

[0063] like Figure 5 As shown, when viewed in a direction perpendicular to the third side 13, the angle (first angle θ1) formed by the first side 11 and the second side 12 is, for example, 90°. When viewed in a direction perpendicular to the third side 13, the angle (first angle θ1) formed by the first side 11 and the second side 12 can be, for example, greater than 70° and less than 110°. The angle formed by the fifth side 15 and the fourth side 14 is, for example, 90°. The angle formed by the sixth side 16 and the fourth side 14 is, for example, 90°.

[0064] Figure 6 This is a side view schematic diagram showing the structure of the cutting insert 1 according to the first embodiment. Figure 6 The side shown is viewed from a direction perpendicular to the fourth side 14. (As shown) Figure 6 As shown, the interface 60 between the base component 50 and the cutting component 30 is provided along a plane parallel to the third side surface 13. The case where the interface 60 between the base component 50 and the cutting component 30 is provided along a plane parallel to the third side surface 13 includes the case where the interface 60 is completely parallel to the third side surface 13 and the case where the interface 60 is substantially parallel to the third side surface 13. The case where the interface 60 is substantially parallel to the third side surface 13 is when the angle formed by the interface 60 and the third side surface 13 is 3° or less.

[0065] The arithmetic mean roughness (Ra) of each of the first side surface 11, the second side surface 12, and the fourth side surface 14 is, for example, 0.5 μm or more. The lower limit of the arithmetic mean roughness of each of the first side surface 11, the second side surface 12, and the fourth side surface 14 is not particularly limited; for example, it can be 0.7 μm or more, or 1.0 μm or more. The upper limit of the arithmetic mean roughness of each of the first side surface 11, the second side surface 12, and the fourth side surface 14 is not particularly limited; for example, it can be 4.0 μm or less, or 3.5 μm or less.

[0066] Similarly, the arithmetic mean roughness of each of the 5th side surface 15, the 6th side surface 16, and the 7th side surface 17 is, for example, 0.5 μm or more. The lower limit of the arithmetic mean roughness of each of the 5th side surface 15, the 6th side surface 16, and the 7th side surface 17 is not particularly limited; for example, it can be 0.7 μm or more, or 1.0 μm or more. The upper limit of the arithmetic mean roughness of each of the 5th side surface 15, the 6th side surface 16, and the 7th side surface 17 is not particularly limited; for example, it can be 4.0 μm or less, or 3.5 μm or less.

[0067] The arithmetic mean roughness of the third side 13 can be less than the arithmetic mean roughness of the first side 11, the second side 12 and the fourth side 14. The arithmetic mean roughness of the third side 13 can be less than the arithmetic mean roughness of the fifth side 15, the sixth side 16 and the seventh side 17.

[0068] Next, the method for measuring the arithmetic mean roughness of each of the above-mentioned surfaces will be explained. The arithmetic mean roughness of each of the above-mentioned surfaces can be measured using a surface roughness measuring apparatus (SURFCOM NEX 041) manufactured by Tokyo Seimitsu Co., Ltd. The measurement conditions for the arithmetic mean roughness are as follows: The measurement length is set to 3 mm. The measurement speed is set to 0.3 mm / s. The cutoff wavelength is set to 0.8 mm. The calculation standard is set to JIS (Japan Industrial Standard) '01 / '13.

[0069] Next, the structure of the cage 2 according to the first embodiment will be described.

[0070] Figure 7 This is a perspective view showing the structure of the cage 2 according to the first embodiment. Figure 8 This is a top view schematic diagram showing the structure of the cage 2 according to the first embodiment. (See attached diagram.) Figure 7 and Figure 8 As shown, the cage 2 has a front end face 74, a rear end face 75, and an outer peripheral face 76. The outer peripheral face 76 is connected to the front end face 74. The rear end face 75 is connected to the outer peripheral face 76 from the opposite side of the front end face 74. Figure 8As shown, the rear end face 75 has a first rear end face 77 and a second rear end face 78. The second rear end face 78 is connected to the first rear end face 77. The first rear end face 77 is inclined relative to the second rear end face 78. In the axial direction of the cage 2, the first rear end face 77 is located between the front end face 74 and the second rear end face 78.

[0071] like Figure 7 and Figure 8 As shown, the outer peripheral surface 76 has a first outer peripheral surface 81, a second outer peripheral surface 82, and a third outer peripheral surface 83. The first outer peripheral surface 81 is connected to the front end surface 74. The third outer peripheral surface 83 is connected to the rear end surface 75. The second outer peripheral surface 82 is located between the first outer peripheral surface 81 and the third outer peripheral surface 83. The second outer peripheral surface 82 is connected to both the first outer peripheral surface 81 and the third outer peripheral surface 83. The diameter of the third outer peripheral surface 83 may be larger than the diameter of the first outer peripheral surface 81. The diameter of the second outer peripheral surface 82 may monotonically increase from the first outer peripheral surface 81 toward the third outer peripheral surface 83.

[0072] The boring bar 10 according to the first embodiment is a small tool. The outer diameter D of the front end face 74 of the retainer 2 is, for example, 2 mm or more and 10 mm or less. The lower limit of the outer diameter D of the front end face 74 is not particularly limited, for example, it can be 3 mm or more, or 3.5 mm or more. The upper limit of the outer diameter D of the front end face 74 is not particularly limited, for example, it can be 8.0 mm or less, or 6 mm or less.

[0073] Figure 9 It is along Figure 8 A cross-sectional view of the IX-IX line. Figure 9 The cross-section shown includes the central axis X of the retainer 2 and is parallel to the direction in which the second hole 72 extends (second direction 102). A first hole 71 and a second hole 72 are formed in the retainer 2. The first hole 71 opens at the front end face 74. The first hole 71 extends axially (first direction 101) from the front end face 74. The second hole 72 connects to the first hole 71. The second hole 72 opens at the outer peripheral face 76. Specifically, the second hole 72 opens at the first outer peripheral face 81. The second hole 72 extends radially perpendicular to the axial direction. The second hole 72 can be a through hole through which the retainer 2 passes, or a bottomed hole that does not pass through the retainer 2.

[0074] The retainer 2 may have a coolant supply hole 73, a coolant inlet hole 85, and a connecting hole 84. The coolant supply hole 73 opens on the outer peripheral surface 76. Specifically, the coolant supply hole 73 opens on the first outer peripheral surface 81. The coolant supply hole 73 can be connected to a second hole 72. The direction in which the coolant supply hole 73 extends can be inclined relative to both the first direction 101 (axial) and the second direction 102 (radial). The coolant inlet hole 85 is provided along the first direction 101. The coolant inlet hole 85 opens on the first rear end surface 77 of the rear end surface 75. The coolant inlet hole 85 is a hole for introducing coolant. The connecting hole 84 is connected to both the coolant inlet hole 85 and the coolant supply hole 73. The connecting hole 84 is located between the coolant inlet hole 85 and the coolant supply hole 73. The coolant supply hole 73 is, for example, a hole for supplying a fluid such as a liquid or gas. This fluid can cool the cutting edge 34 or blow away chips.

[0075] like Figure 9 As shown, when viewed along directions perpendicular to both the first direction 101 and the second direction 102, the width of the connecting hole 84 along the second direction 102 can expand as it extends from the coolant inlet hole 85 toward the coolant supply hole 73. Sometimes, the base end side of the retainer 2 is made of hard alloy, and the front end side of the retainer 2 is made of steel, and the two are joined together, with the connecting hole 84 in between. In this case, when machining the coolant supply hole 73 after joining, if the connecting hole 84 is large, it can prevent the drill bit from contacting the hard alloy on the base end side of the retainer 2 and breaking.

[0076] Figure 10 This is a front view showing the structure of the cage 2 according to the first embodiment. Figure 11 It is along Figure 10 A cross-sectional view of the XI-XI line. Figure 11 The cross-section shown includes the central axis X of the cage 2 and is parallel to the third direction 103. The third direction 103 is orthogonal to both the first direction 101 and the second direction 102.

[0077] like Figure 10 and Figure 11 As shown, the retainer 2 has a stop portion 79. The stop portion 79 covers at least a portion of the second hole 72. The stop portion 79 can completely cover the second hole 72. The stop portion 79 is provided along the outer peripheral surface 76.

[0078] like Figure 11As shown, the surface 90 constituting the second hole 72 has, for example, a first inner surface 91, a second inner surface 92, a third inner surface 93, a fourth inner surface 94, and a fifth inner surface 95. The fifth inner surface 95 is connected to both the first and second inner surfaces 91 and 92. The fifth inner surface 95 is located between the first and second inner surfaces 91 and 92. The fifth inner surface 95 is a concave curved surface. The second inner surface 92 is inclined relative to the first inner surface 91. The first inner surface 91 is connected to the third inner surface 93. The third inner surface 93 is inclined relative to the first inner surface 91. The second inner surface 92 is connected to the fourth inner surface 94. The fourth inner surface 94 is inclined relative to the second inner surface 92. The fourth inner surface 94 is opposite to the third inner surface 93. The fourth inner surface 94 can be parallel to the third inner surface 93. The third inner surface 93 and the fourth inner surface 94 can each be parallel to the central axis X.

[0079] like Figure 11 As shown, when viewed along the extension direction of the second hole 72, the distance between the first inner surface 91 and the second inner surface 92 decreases as it moves from the front end face 74 toward the rear end face 75. The distance between the first inner surface 91 and the second inner surface 92 is the distance along the third direction 103. The first inner surface 91 is inclined towards the third inner surface 93 relative to the central axis X. The second inner surface 92 is inclined towards the fourth inner surface 94 relative to the central axis X. The angle formed by the first inner surface 91 and the second inner surface 92 (the second angle θ2) is, for example, 90°. The second angle θ2 can be, for example, greater than 70° and less than 110°. The lower limit of the second angle θ2 is not particularly limited; for example, it can be greater than 75° or greater than 80°. The upper limit of the second angle θ2 is not particularly limited; for example, it can be less than 105° or less than 100°. The second angle θ2 can be the same as the first angle θ1 or slightly smaller than the first angle θ1. For example, the second angle θ2 can be a smaller angle than the first angle θ1 by more than 10 minutes but less than 50 minutes. When viewed along the extension direction of the second hole 72, the width of the connecting hole 84 along the third direction 103 can narrow as it moves from the coolant inlet hole 85 toward the coolant supply hole 73. For example... Figure 8 As shown, the coolant supply hole 73 opens in the region between the first inner surface 91 and the second inner surface 92. Figure 9 As shown, the coolant supply hole 73 can open on the fifth inner side 95.

[0080] Next, the detailed structure of the boring bar 10 according to the first embodiment will be described.

[0081] Figure 12 This is a top view schematic diagram showing the structure of the boring bar 10 according to the first embodiment. Figure 13 It is along Figure 12 A cross-sectional view of line XIII-XIII. Figure 13 The cross-section shown includes the central axis X and is parallel to the direction in which the second hole 72 extends (second direction 102).

[0082] like Figure 12 and Figure 13 As shown, the cutting insert 1 is disposed in the second hole 72. The base component 50 of the cutting insert 1 is disposed in the second hole 72. The cutting edge 34 of the cutting insert 1 is disposed on the outer side of the second hole 72. The third side surface 13 of the base component 50 is in contact with the stop portion 79. A portion of the third side surface 13 is in contact with the stop portion 79, while the remaining portion of the third side surface 13 can be separated from the stop portion 79. A gap can be provided between the stop portion 79 and the fifth inner side surface 95. Chips can be discharged through this gap.

[0083] Figure 14 This is a front view showing the structure of the boring bar 10 according to the first embodiment. Figure 15 It is along Figure 14 A cross-sectional view of the XV-XV line. Figure 15 The cross-section shown includes the central axis X and is parallel to the third direction 103.

[0084] like Figure 14 and Figure 15 As shown, the pressing member 3, when positioned in the first hole 71, contacts the fourth side surface 14 of the cutting insert 1. The pressing member 3 has a head 4 and an external threaded portion 5. An internal threaded portion 6 is formed on the surface constituting the first hole 71 (see reference). Figure 2 The external threaded portion 5 engages with the internal threaded portion 6. The external threaded portion 5 is disposed in the first hole 71. The pressing member 3 is screwed into the first hole 71. The end of the external threaded portion 5 on the rear end face 75 side is located in the second hole 72. The external threaded portion 5 is in contact with the fourth side face 14 of the cutting insert 1 in the second hole 72.

[0085] The pressing member 3 presses the cutting insert 1 from the front end face 74 toward the rear end face 75. The cutting insert 1 is pushed towards the retainer 2 by the pressing member 3. The first side 11 of the cutting insert 1 is in contact with the first inner side 91 of the retainer 2. The first side 11 is pushed against the first inner side 91 by the pressing force of the pressing member 3. The second side 12 of the cutting insert 1 is in contact with the second inner side 92. The second side 12 is pushed against the second inner side 92 by the pressing force of the pressing member 3. In this manner, the cutting insert 1 is securely fixed to the retainer 2.

[0086] Next, a method for machining the cylindrical component 100 using the boring bar 10 according to the first embodiment will be described.

[0087] Figure 16This is a perspective view illustrating a method for machining a cylindrical component 100 using the boring bar 10 according to the first embodiment. First, the cylindrical component 100 is prepared as the material to be cut. The cylindrical component 100 is, for example, the nut portion of a ball screw. Figure 16 Only the lower half of the cylindrical component 100 is shown. Figure 16 As shown, the cylindrical component 100 has an outer wall surface 111, an inner wall surface 112, a first side wall surface 113, and a second side wall surface 114. The inner wall surface 112 is located inside the outer wall surface 111. The first side wall surface 113 is connected to both the outer wall surface 111 and the inner wall surface 112. The second side wall surface 114 is connected to both the outer wall surface 111 and the inner wall surface 112.

[0088] Next, the cylindrical component 100 is cut using a boring bar 10. The boring bar 10 is mounted on a connector 200. The connector 200 has a main body 201 and a fixing screw 202. A portion of the holder 2 of the boring bar 10 is mounted on the main body 201 of the connector 200. The holder 2 of the boring bar 10 is fixed to the main body 201 using the fixing screw 202.

[0089] Next, the boring bar 10 is inserted into the space surrounded by the inner wall surface 112 of the cylindrical member 100. The diameter of the front end face 74 of the boring bar 10 is smaller than the diameter of the space surrounded by the inner wall surface 112 of the cylindrical member 100. The cylindrical member 100 rotates about its rotation axis. The boring bar 10 does not rotate while fixed to the coupling 200, but moves linearly in the axial direction relative to the cylindrical member 100. The cutting edge 34 of the cutting member 30 contacts the inner wall surface 112 of the cylindrical member 100. Thus, the inner wall surface 112 of the cylindrical member 100 is turned by the boring bar 10.

[0090] Furthermore, the above description refers to the case where the cylindrical component 100 is the nut portion of a ball screw, but the cylindrical component 100 is not limited to the nut portion of a ball screw.

[0091] (Second Implementation)

[0092] Next, the structure of the cutting insert 1 according to the second embodiment will be described. The main difference between the cutting insert 1 according to the second embodiment and the cutting insert 1 according to the first embodiment is that the widths of the first top surface 41 and the second top surface 31 are larger. Other structural aspects are the same as those of the cutting insert 1 according to the first embodiment. The following description will focus on the structural differences from those of the cutting insert 1 according to the first embodiment.

[0093] Figure 17 This is a perspective view showing the structure of the cutting insert 1 according to the second embodiment. Figure 18 This is a top view schematic diagram showing the structure of the cutting insert 1 according to the second embodiment. (As shown) Figure 17 and Figure 18 As shown, the base component 50 has a protruding component 40. The protruding component 40 has a first top surface 41, a first bottom surface 42, and a first wall surface 43. The cutting component 30 has a second top surface 31, a second bottom surface 32, a second wall surface 33, and a cutting edge 34.

[0094] (Third Implementation)

[0095] Next, the structure of the cutting insert 1 according to the third embodiment will be described. The main difference between the cutting insert 1 according to the third embodiment and the cutting insert 1 according to the first embodiment is that the cutting member 30 is biased towards the fourth side 14. The other structures are the same as those of the cutting insert 1 according to the first embodiment. Hereinafter, the description will focus on the structure that is different from that of the cutting insert 1 according to the first embodiment.

[0096] Figure 19 This is a perspective view showing the structure of the cutting insert 1 according to the third embodiment. Figure 20 This is a top view schematic diagram showing the structure of the cutting insert 1 according to the third embodiment. (As shown) Figure 19 and Figure 20 As shown, the cutting insert 1 according to the third embodiment has a base component 50 and a cutting component 30.

[0097] (Fourth implementation)

[0098] Next, the structure of the cutting insert 1 according to the fourth embodiment will be described. The cutting insert 1 according to the fourth embodiment differs from the cutting insert 1 according to the first embodiment mainly in that the cutting member 30 has a first cutting portion 131 and a second cutting portion 132; the other structures are the same as those of the cutting insert 1 according to the first embodiment. Hereinafter, the description will focus on the structure that differs from that of the cutting insert 1 according to the first embodiment.

[0099] Figure 21 This is a perspective view showing the structure of the cutting insert 1 according to the fourth embodiment. Figure 22 This is a top view schematic diagram showing the structure of the cutting insert 1 according to the fourth embodiment. (See attached diagram.) Figure 21 and Figure 22 As shown, the base component 50 of the cutting insert 1 according to the fourth embodiment has a protruding component 40. The protruding component 40 has a first protrusion 141 and a second protrusion 142. The second protrusion 142 is separate from the first protrusion 141. The first protrusion 141 and the second protrusion 142 each have a first top surface 41, a first bottom surface 42, and a first wall surface 43. The first protrusion 141 is provided along the fourth side surface 14. The second protrusion 142 is provided along the seventh side surface 17.

[0100] like Figure 21 and Figure 22 As shown, the cutting component 30 of the cutting insert 1 according to the fourth embodiment has a first cutting portion 131 and a second cutting portion 132. The second cutting portion 132 is separate from the first cutting portion 131. The first cutting portion 131 and the second cutting portion 132 each have a second top surface 31, a second bottom surface 32, a second wall surface 33, and a cutting edge 34. The first cutting portion 131 is connected to a first protrusion 141. The second cutting portion 132 is connected to a second protrusion 142. The interface 60 between the first cutting portion 131 and the first protrusion 141 can be located on the same plane as the interface 60 between the second cutting portion 132 and the second protrusion 142.

[0101] Next, the effects of the boring bar 10 and the cutting insert 1 involved in the above embodiments will be explained.

[0102] The boring bar 10 according to the above embodiment includes a cutting insert 1, a retainer 2, and a pressing member 3. The cutting insert 1 is mounted on the retainer 2. The pressing member 3 fixes the cutting insert 1 to the retainer 2. The cutting insert 1 includes a base member 50 and a cutting member 30 located on the base member 50. The base member 50 includes a first side surface 11, a second side surface 12, a third side surface 13, and a fourth side surface 14. The retainer 2 includes a front end surface 74, a rear end surface 75, and an outer peripheral surface 76. A first hole 71 and a second hole 72 are formed in the retainer 2. The surface constituting the second hole 72 includes a first inner side surface 91 and a second inner side surface 92 inclined relative to the first inner side surface 91. The first side surface 11 is in contact with the first inner side surface 91. The second side surface 12 is in contact with the second inner side surface 92. The third side surface 13 is in contact with a stop portion 79. When viewed along the extension direction of the second hole 72, the distance between the first inner side surface 91 and the second inner side surface 92 decreases as it moves from the front end face 74 toward the rear end face 75. The first side surface 11 of the cutting insert 1 is pressed against the first inner side surface 91 of the retainer 2 by the pressing member 3, and the second side surface 12 of the cutting insert 1 is pressed against the second inner side surface 92 of the retainer 2.

[0103] The boring bar 10 according to the above embodiment can improve clamping performance through a simple structure. Specifically, the cutting insert 1 is clamped with high precision by the retainer 2. In addition, both the cutting insert 1 and the retainer 2 have simple structures, thus maintaining high strength. Furthermore, both the cutting insert 1 and the retainer 2 have simple structures, thus making them easy to manufacture.

[0104] According to the boring bar 10 of the above embodiment, a coolant supply hole 73 may be provided in the holder 2, which opens in the region between the first inner surface 91 and the second inner surface 92. The direction in which the coolant supply hole 73 extends may be inclined relative to both the axial and radial directions. As a result, coolant can be supplied with high precision to the vicinity of the cutting edge 34 from between the first inner surface 91 and the second inner surface 92.

[0105] According to the boring bar 10 of the above embodiment, the outer diameter D of the front end face 74 can be 2 mm or more and 10 mm or less. When miniaturizing the boring bar 10, the shape of the cutting insert 1 also needs to be reduced. Conventionally, a threaded hole is provided in the cutting insert 1, and a fastening screw is inserted into the threaded hole to fix the cutting insert 1 to the retainer 2. However, according to the boring bar 10 of the above embodiment, even a cutting insert 1 without a threaded hole can be fixed to the retainer 2. Therefore, compared with a cutting insert 1 provided with a threaded hole, high strength can be maintained and the cutting insert 1 can be reduced in size. As a result, the boring bar 10 can be miniaturized.

[0106] According to the cutting insert 1 of the above embodiment, there is a base member 50 and a cutting member 30 disposed on the base member 50. The base member 50 includes a first side 11, a second side 12, a third side 13, and a fourth side 14. The second side 12 is inclined relative to the first side 11. The third side 13 is inclined relative to each of the first side 11 and the second side 12 and is connected to each of the first side 11 and the second side 12. The fourth side 14 is inclined relative to each of the first side 11, the second side 12, and the third side 13, is separate from each of the first side 11 and the second side 12, and is connected to the third side 13. When viewed in a direction perpendicular to the third side 13, the distance between the first side 11 and the second side 12 decreases as it moves away from the fourth side 14. The interface 60 between the base member 50 and the cutting member 30 is provided along a plane parallel to the third side 13.

[0107] The cutting insert 1 according to the above embodiment can improve clamping performance through a simple structure. In the cutting insert 1 according to the above embodiment, no screw holes for clamping are formed. Therefore, even when the cutting insert 1 is miniaturized, high strength can be maintained.

[0108] According to the cutting insert 1 of the above embodiment, the arithmetic mean roughness of each of the first side surface 11, the second side surface 12, and the fourth side surface 14 can be 0.5 μm or more. The arithmetic mean roughness of the third side surface 13 can be less than the arithmetic mean roughness of each of the first side surface 11, the second side surface 12, and the fourth side surface 14. Each of the first side surface 11, the second side surface 12, and the fourth side surface 14 can be formed by electrical discharge wire cutting. Since the first side surface 11, the second side surface 12, and the fourth side surface 14 are formed by cutting, their respective arithmetic mean roughness increases. The cutting insert 1 can be easily manufactured without the need for grinding of each of the first side surface 11, the second side surface 12, and the fourth side surface 14. On the other hand, the third side surface 13 is finished by grinding. Therefore, the arithmetic mean roughness of the third side surface 13 decreases. As a result, the position of the cutting edge 34 in the direction perpendicular to the third side surface 13 can be adjusted with high precision.

[0109] The embodiments disclosed herein should be considered illustrative in all respects and are not restrictive. The scope of the invention is defined not by the foregoing description but by the claims, including all modifications within the meaning and scope of the claims.

[0110] Explanation of the label

[0111] 1. Cutting insert, 2. Retainer, 3. Pressing component, 4. Head, 5. External thread, 6. Internal thread, 10. Boring tool, 11. First side, 12. Second side, 13. Third side, 14. Fourth side, 15. Fifth side, 16. Sixth side, 17. Seventh side, 18. Eighth side, 19. Ninth side, 20. Tenth side, 21. First region, 22. Second region, 23. Third region, 30. Cutting component, 31. Second top surface, 32. Second bottom surface, 33. Second wall surface, 34. Cutting edge, 40. Protruding component, 41. First top surface, 42. First bottom surface, 43. First wall surface, 50. Base component, 60. Interface, 71. First hole, 72. Second hole, 73. Coolant supply hole, 74. Front end face, 75. Rear end face, 76. Outer peripheral surface, 77. First rear end face. 78. Face, 79. Second rear end face, 81. Stop, 82. First outer peripheral face, 83. Third outer peripheral face, 84. Connecting hole, 85. Coolant inlet hole, 90. Face, 91. First inner surface, 92. Second inner surface, 93. Third inner surface, 94. Fourth inner surface, 95. Fifth inner surface, 100. Cylindrical component, 101. First direction, 102. Second direction, 103. Third direction, 111. Outer wall surface, 112. Inner wall surface, 113. First side wall surface, 114. Second side wall surface, 131. First cutting part, 132. Second cutting part, 141. First protrusion, 142. Second protrusion, 200. Connector, 201. Main body, 202. Fixing screw, D. Outer diameter, X. Central axis, θ1. First angle, θ2. Second angle.

Claims

1. A boring tool, comprising: Cutting inserts; A retainer for mounting the cutting insert; and The pressing component secures the cutting insert to the retainer. The cutting insert includes a base component and a cutting component located on the base component. The base component includes: First side view; The second side is inclined relative to the first side; A third side, which is inclined relative to the first side and the second side respectively and is connected to the first side and the second side respectively; and The fourth side is inclined relative to the first, second, and third sides, and is separate from the first and second sides but connected to the third side. The cage comprises: Front end; The outer peripheral surface, which is connected to the front end surface; and The rear end face is connected to the outer peripheral face from the opposite side of the front end face. The cage is formed with: A first hole, which opens on the front end face and extends axially from the front end face; and The second hole, which is connected to the first hole, opens on the outer peripheral surface and extends radially perpendicular to the axis. The retainer includes a stop that covers at least a portion of the second hole. The surface constituting the second hole includes a first inner surface and a second inner surface inclined relative to the first inner surface. The pressing component is in contact with the fourth side when it is positioned in the first hole. The base component is disposed in the second hole. The first side surface is connected to the first inner side surface. The second side surface is connected to the second inner side surface. The third side is in contact with the stop portion. When viewed along the extension direction of the second hole, the distance between the first inner side surface and the second inner side surface decreases as viewed from the front end surface toward the rear end surface. The first side, the second side, the third side, and the fourth side are each planar.

2. The boring tool according to claim 1, wherein, The cutting component is made of cubic boron nitride.

3. The boring tool according to claim 1, wherein, The cutting component is made of sintered diamond.

4. The boring tool according to any one of claims 1 to 3, wherein, The retainer is provided with a coolant supply hole, which opens in the region between the first inner surface and the second inner surface. The coolant supply hole extends in a direction that is inclined relative to both the axial and radial directions.

5. The boring tool according to any one of claims 1 to 3, wherein, The outer diameter of the front end face is more than 2 mm and less than 10 mm.

6. The boring tool according to any one of claims 1 to 3, wherein, The angle between the first inner surface and the second inner surface is greater than 70° and less than 110°.

7. The boring tool according to claim 1, wherein, The cutting component is made of cubic boron nitride. The retainer is provided with a coolant supply hole, which opens in the region between the first inner surface and the second inner surface. The coolant supply orifice extends in an inclined direction relative to both the axial and radial directions. The outer diameter of the front end face is more than 2 mm and less than 10 mm.

8. A method for processing a cylindrical component, comprising the following steps: Prepare a cylindrical component having an outer wall surface and an inner wall surface located inside the outer wall surface; and The cylindrical component is cut using the boring tool according to any one of claims 1 to 7. During the cutting process of the cylindrical component, the cutting component comes into contact with the inner wall surface.

9. A cutting insert, comprising: Base components; and The cutting component is located on the base component. The base component includes: First side view; The second side is inclined relative to the first side; A third side, which is inclined relative to the first side and the second side respectively and is connected to the first side and the second side respectively; and The fourth side is inclined relative to the first, second, and third sides, and is separate from the first and second sides but connected to the third side. When viewed in a direction perpendicular to the third side, the distance between the first and second sides decreases as the distance from the fourth side increases. The interface between the base component and the cutting component is provided along a plane parallel to the third side surface. The arithmetic mean roughness of each of the first, second, and fourth side surfaces is 0.5 μm or greater. The arithmetic mean roughness of the third side is less than the arithmetic mean roughness of the first side, the second side, and the fourth side. The first side, the second side, the third side, and the fourth side are each planar.

10. The cutting insert according to claim 9, wherein, The cutting component is made of cubic boron nitride.

11. The cutting insert according to claim 9, wherein, The cutting component is made of sintered diamond.

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