Cutting insert and rotary cutting tool

Abstract

This cutting insert has a base member and a blade edge member. The blade edge member has a rake face and a flank face that is contiguous to the rake face. The ridgeline between the rake face and the flank face forms a cutting edge. The base member is provided with a flow passage through which a fluid passes. The base member has: a front end face at which the blade edge member is disposed; a back end face which is located opposite to the front end face; a first side face which is located between the front end face and the back end face and is provided with the inlet of the flow passage; and a second side face which is located opposite to the first side face and is provided with the outlet of the flow passage. The back end face has a planar shape. The first side face has a planar shape. A virtual plane along the back end face and a virtual plane along the first side face are perpendicular to each other. A vector parallel to the direction in which the fluid flows out of the outlet and which is the tangential direction of the outlet of the flow passage has a component in a first direction which is perpendicular to the back end face and directed toward the back end face from the front end face. Said component is positive.

Description

Cutting inserts and rotary cutting tools

[0001] The present disclosure relates to cutting inserts and rotary cutting tools.

[0002] WO 2019 / 220528 (Patent Document 1) discloses a cutting insert provided with coolant supply holes.

[0003] International Publication No. 2019 / 220528

[0004] A cutting insert according to the present disclosure is for use in a rotary cutting tool and includes a base member and a cutting edge member attached to the base member. The cutting edge member has a rake face and a flank face connected to the rake face. A ridgeline between the rake face and the flank face forms a cutting edge. The base member is provided with a flow path through which a fluid passes. The base member has a front end surface on which the cutting edge member is disposed, a rear end surface opposite the front end surface, a first side surface between the front end surface and the rear end surface and provided with an inlet of the flow path, and a second side surface opposite the first side surface and provided with an outlet of the flow path. The rear end surface is planar. The first side surface is planar. An imaginary plane along the rear end surface and an imaginary plane along the first side surface are perpendicular. A vector in a direction in which the fluid flows out of the outlet and which is parallel to a tangent direction of the outlet of the flow path has a component in a first direction that is perpendicular to the rear end surface and extends from the front end surface to the rear end surface, and the component is positive.

[0005] FIG. 1 is a first perspective schematic view showing the configuration of a cutting insert according to a first embodiment. FIG. 2 is a second perspective schematic view showing the configuration of a cutting insert according to the first embodiment. FIG. 3 is a cross-sectional schematic view showing the configuration of a cutting insert according to the first embodiment. FIG. 4 is a front schematic view showing the shape of an outlet of a flow channel. FIG. 5 is a cross-sectional schematic view showing the configuration of a cutting insert according to a second embodiment. FIG. 6 is a perspective schematic view showing the configuration of a cutting insert according to a third embodiment. FIG. 7 is a perspective schematic view showing the configuration of a cutting insert according to a fourth embodiment. FIG. 8 is a cross-sectional schematic view showing the configuration of a cutting insert according to the fourth embodiment. FIG. 9 is a perspective schematic view showing the configuration of a rotary cutting tool according to this embodiment. FIG. 10 is a front schematic view showing the configuration of a rotary cutting tool according to this embodiment. FIG. 11 is a cross-sectional schematic view taken along line XI-XI in FIG. 10. FIG. 12 is a cross-sectional schematic view taken along line XII-XII in FIG. 10. FIG. 13 is a cross-sectional schematic view showing a state in which a workpiece is cut using the rotary cutting tool.

[0006] [Description of Embodiments of the Present Disclosure] First, embodiments of the present disclosure (also referred to as the present embodiments) will be listed and described.

[0007] (1) A cutting insert according to the present disclosure is for a rotary cutting tool and includes a base member and a cutting edge member attached to the base member. The cutting edge member has a rake face and a flank face continuous with the rake face. A ridgeline between the rake face and the flank face forms a cutting edge. The base member is provided with a flow path through which a fluid passes. The base member has a front end surface on which the cutting edge member is disposed, a rear end surface opposite the front end surface, a first side surface between the front end surface and the rear end surface and provided with an inlet of the flow path, and a second side surface opposite the first side surface and provided with an outlet of the flow path. The rear end surface is planar. The first side surface is planar. An imaginary plane along the rear end surface and an imaginary plane along the first side surface are perpendicular. A vector in a direction in which the fluid flows out of the outlet and parallel to a tangent direction of the outlet of the flow path has a component in a first direction perpendicular to the rear end surface and directed from the front end surface to the rear end surface, the component being positive. This allows the fluid to be discharged behind the cutting edge, which reduces the amount of chips that get into recesses in the workpiece.

[0008] (2) According to the cutting insert of (1), the flow path may have a first flow path portion that forms an inlet and stores the fluid, and a second flow path portion that forms an outlet and is connected to the first flow path portion. This allows the cutting insert to be lightweight. As a result, the rotary cutting tool can be rotated at high speed.

[0009] (3) According to the cutting insert of (1) or (2), the width of the outlet in a direction perpendicular to the rake face in a front view of the outlet may be larger than the width of the outlet in a direction parallel to the rake face. This increases the amount of fluid discharged. As a result, it is possible to further reduce the amount of chips entering the recess provided in the workpiece.

[0010] (4) In the cutting insert according to any one of (1) to (3) above, in a cross section parallel to the first direction and intersecting the inlet and the outlet, the angle between the direction in which the fluid flows into the inlet and the tangential direction of the inlet of the flow channel and the second direction opposite the first direction may be between 0° and 90°, and the angle between the direction in which the fluid flows out of the outlet and the tangential direction of the outlet of the flow channel and the second direction may be between 90° and 180°. This allows the fluid to be discharged from the outlet of the flow channel in a region close to the cutting edge. As a result, it is possible to further reduce the amount of chips entering the recess provided in the workpiece.

[0011] (5) According to the cutting insert of (2) above, in a front view of the outlet, the width of the outlet in a direction perpendicular to the rake face may be greater than the width of the outlet in a direction parallel to the rake face. In a cross section parallel to the first direction and intersecting the inlet and the outlet, the angle between a direction in which the fluid flows into the inlet and a tangential direction of the inlet of the flow path and a second direction opposite the first direction may be greater than or equal to 0° and less than or equal to 90°, and the angle between a direction in which the fluid flows out of the outlet and a tangential direction of the outlet of the flow path and the second direction may be greater than 90° and less than or equal to 180°. This increases the amount of fluid discharged. Furthermore, the fluid can be released from the outlet of the flow path in a region close to the cutting edge. As a result, chips can be further reduced from entering the recess provided in the workpiece.

[0012] (6) According to the cutting insert according to any one of (1) to (5) above, a protruding wall portion may be provided on the second side surface. The outlet may open to the side surface of the protruding wall portion. The protruding wall portion can prevent chips from moving forward of the cutting edge. As a result, it is possible to further reduce chips from entering recesses provided in the workpiece.

[0013] (7) According to the cutting insert according to any one of (1) to (6) above, the number of outlets may be two or more.

[0014] (8) A rotary cutting tool according to the present disclosure is rotatable about an axis and includes a cutting insert and a body to which the cutting insert is attached. The cutting insert includes a base member and a cutting edge member attached to the base member. The cutting edge member has a rake face and a flank face continuous with the rake face. The ridges of the rake face and the flank face form a cutting edge. The base member is provided with a flow path through which a fluid passes. The base member has a front end face on which the cutting edge member is disposed, a rear end face opposite the front end face, a first side face between the front end face and the rear end face and provided with an inlet of the flow path, and a second side face opposite the first side face and provided with an outlet of the flow path. The body member has a first side face facing the workpiece and a second side face opposite the first side. In a cross section parallel to the axis and intersecting the inlet and outlet, the direction in which the fluid flows out of the outlet and the tangential direction of the outlet of the flow path are parallel to the axis and form an angle greater than 90° and less than 180° with the forward direction of the axis extending from the second surface to the first surface. This allows the fluid to be discharged in the direction opposite to the direction in which the workpiece is located. As a result, it is possible to reduce the amount of chips entering the recesses provided in the workpiece.

[0015] (9) According to the rotary cutting tool of (8), the main body may be provided with a third flow passage portion through which a fluid passes. The third flow passage portion may have a main body outlet connected to the flow passage and a main body inlet opposite the main body outlet. In a cross section parallel to the axis and intersecting the main body inlet and the main body outlet, the angle between the direction from the main body inlet to the main body outlet and the forward axis may be greater than 0° and less than 90°. This allows the fluid to be discharged from the flow passage outlet in a region close to the cutting edge. As a result, it is possible to further reduce the amount of chips entering recesses provided in the workpiece.

[0016] Specific examples of embodiments of the present disclosure will be described below with reference to the drawings. In the following drawings, the same or corresponding parts are designated by the same reference numerals, and descriptions thereof will not be repeated.

[0017] (First embodiment) Fig. 1 is a first perspective schematic view showing the configuration of a cutting insert according to a first embodiment. As shown in Fig. 1, the cutting insert 1 according to the first embodiment is for a rotary cutting tool and has a base member 10 and a cutting edge member 20. The cutting edge member 20 is attached to the base member 10. The cutting edge member 20 has a rake face 21 and a flank face 22. The flank face 22 is continuous with the rake face 21. The ridge line between the rake face 21 and the flank face 22 forms a cutting edge 23.

[0018] FIG. 2 is a second perspective schematic view showing the configuration of the cutting insert 1 according to the first embodiment. As shown in FIGS. 1 and 2 , the base member 10 has a front end surface 15, a rear end surface 16, a first side surface 11, a second side surface 12, a third side surface 13, and a fourth side surface 14. The front end surface 15 faces the workpiece. The rear end surface 16 is located opposite the front end surface 15. The rear end surface 16 is flat. The direction from the front end surface 15 to the rear end surface 16 is defined as a first direction R1 (see FIG. 3 ). The first direction R1 is perpendicular to the rear end surface 16. The direction opposite to the first direction R1 is defined as a second direction R2 (see FIG. 3 ). A cutting edge member 20 is disposed on the front end surface 15. A portion of the cutting edge 23 formed by the cutting edge member 20 is located in the second direction R2 relative to the front end surface 15.

[0019] The base member 10 is provided with a flow path 50. A fluid passes through the flow path 50. The fluid is, for example, a coolant, but is not limited to a coolant. The fluid may be a liquid, a gas, or a mist.

[0020] The base member 10 has an inlet (hereinafter also referred to as a first opening 41) of the flow path 50 and an outlet (hereinafter also referred to as a second opening 42) of the flow path 50. The first opening 41 is provided on the first side surface 11. The first side surface 11 is located between the front end surface 15 and the rear end surface 16. The first side surface 11 is flat. An imaginary plane along the rear end surface 16 and an imaginary plane along the first side surface 11 are perpendicular to each other. The second opening 42 is provided on the second side surface 12. The second side surface 12 is located opposite the first side surface 11. The second side surface 12 is located between the front end surface 15 and the rear end surface 16. The fluid enters the flow path 50 through the first opening 41. The fluid exits the flow path 50 through the second opening 42.

[0021] The base member 10 is provided with a mounting screw arrangement hole 2. The mounting screw arrangement hole 2 penetrates the base member 10. A mounting screw 3 is arranged in the mounting screw arrangement hole 2 (see FIG. 9 ). The mounting screw arrangement hole 2 opens to each of the first side surface 11 and the second side surface 12. In a direction parallel to the first direction R1, the mounting screw arrangement hole 2 is located between the second opening 42 and the rear end surface 16. The cutting insert 1 is attached to the main body portion 70 using the mounting screw 3 (see FIG. 9 ).

[0022] The fourth side surface 14 is opposite the third side surface 13. In the direction from the third side surface 13 toward the fourth side surface 14, the cutting edge member 20 is disposed between the third side surface 13 and the fourth side surface 14. In the direction parallel to the first direction R1, each of the third side surface 13 and the fourth side surface 14 is located between the front end surface 15 and the rear end surface 16.

[0023] 3 is a cross-sectional view showing the configuration of the cutting insert 1 according to the first embodiment. The cross section shown in FIG. 3 is parallel to the first direction R1 and intersects with each of the inlet and outlet of the flow channel 50.

[0024] 3, the flow path 50 has a first flow path section 51 and a second flow path section 52. The first flow path section 51 forms an inlet (first opening 41) of the flow path 50. A fluid accumulates in the first flow path section 51. The second flow path section 52 forms an outlet (second opening 42) of the flow path 50. The second flow path section 52 is connected to the first flow path section 51. The second flow path section 52 is located downstream of the first flow path section 51. The volume of the first flow path section 51 may be larger than the volume of the second flow path section 52.

[0025] A third opening 43 is provided on the side surface of the first flow path section 51. The third opening 43 is the inlet of the second flow path section 52. The fluid enters the second flow path section 52 through the third opening 43. The direction in which the fluid enters the first flow path section 51 through the first opening 41 is referred to as a first flow direction A1. In a cross section parallel to the first direction R1 and intersecting each of the inlet and outlet of the flow path 50, the first flow direction A1 may be, for example, perpendicular to the second direction R2 or may be inclined with respect to a line perpendicular to the second direction R2. The direction in which the fluid enters the second flow path section 52 through the third opening 43 is referred to as a second flow direction A2. The second flow direction A2 is, for example, substantially the same direction as the second direction R2. The cross section shown in FIG. 3 includes the center of the second opening 42 and the center of the third opening 43. In this specification, the center of an opening is defined as the midpoint between the two points where the opening intersects with a straight line in the direction in which the width of the opening is greatest, as viewed in the flow direction of the fluid passing through the opening.

[0026] The direction in which the fluid flows out of the second opening 42 and the tangential direction of the second opening 42 are defined as the third flow direction A3. A vector parallel to the third flow direction A3 has a component in the first direction R1. This component is positive. From another perspective, the angle between the third flow direction A3 and the second direction R2 (hereinafter also referred to as the first angle θ1) is greater than 90° and less than or equal to 180°. The first angle θ1 may be greater than 100°, greater than 110°, or greater than 120°. The first angle θ1 may be less than or equal to 170°, less than or equal to 160°, or less than or equal to 150°. The tangential direction of the second opening 42 is measured at a position in the second flow path section 52 closest to the second opening 42, excluding the chamfered portion of the second opening 42.

[0027] As shown in FIGS. 1 and 3 , a protruding wall portion 19 is provided on the second side surface 12. The protruding wall portion 19 is continuous with the front end surface 15. The protruding wall portion 19 has a first region 31 and a second region 32. The first region 31 extends along the first direction R1. The second region 32 is continuous with the first region 31. The second region 32 is located closer to the first region 31 in the first direction R1. The second region 32 is inclined with respect to the first region 31. The second region 32 is located on the opposite side of the front end surface 15 from the first region 31. An outlet of the flow path 50 is provided in the second region 32.

[0028] The second side surface 12 has a third region 33 and a fourth region 34. The third region 33 is located in the first direction R1 relative to the second region 32. The third region 33 is continuous with the second region 32 (see FIG. 1 ). The third region 33 is curved so as to be concave. The fourth region 34 is located in the first direction R1 relative to the third region 33. The fourth region 34 is continuous with the third region 33. The fourth region 34 extends along the first direction R1. The mounting screw arrangement hole 2 opens into the fourth region 34.

[0029] Chips of the workpiece cut by the cutting edge 23 move from the cutting edge 23 toward the third region 33, where they curl and are broken up. The broken up chips are blown in the third flow direction A3 by the fluid exiting from the second opening 42 of the flow path 50. Note that part of the fluid exiting from the second opening 42 of the flow path 50 may hit the third region 33.

[0030] FIG. 4 is a front schematic view showing the shape of the outlet of the flow path 50. As shown in FIG. 4, the second opening 42, which is the outlet of the flow path 50, has an elongated shape. Specifically, in a front view of the second opening 42, the width of the outlet in a direction perpendicular to the rake face 21 (first width W1) may be larger than the width of the outlet in a direction parallel to the rake face 21 (second width W2). Note that the front view of the second opening 42 is a field of view seen in the direction opposite to the third flow direction A3. The first width W1 may be 1.5 times or more, or may be 2 times or more, the second width W2. The first width W1 may be 10 times or less, or may be 5 times or less, the second width W2.

[0031] Second Embodiment Next, the configuration of the cutting insert 1 according to the second embodiment will be described. The cutting insert 1 according to the second embodiment is substantially the same as the cutting insert 1 according to the first embodiment, except that the fluid flow path 50 does not have a flow path portion where the fluid accumulates. The following description will focus on the configuration that differs from the cutting insert 1 according to the first embodiment.

[0032] 5 is a cross-sectional view schematically illustrating the configuration of the cutting insert 1 according to the second embodiment. The cross-sectional view shown in FIG. 5 corresponds to the cross-sectional view shown in FIG.

[0033] 5 , the fluid flow path 50 does not have a flow path portion where the fluid accumulates. The width of the flow path 50 in the second direction R2 may continuously decrease. The first opening 41 forming the inlet of the flow path 50 has a first opening end 41 a and a second opening end 41 b. In the second direction R2, the second opening end 41 b is located between the first opening end 41 a and the front end face 15.

[0034] The direction in which the fluid flows into the flow channel 50 and is tangent to the flow channel 50 at the first opening end 41a is defined as a seventh tangential direction A7. The angle between the second direction R2 and the seventh tangential direction A7 is defined as a seventh angle θ7. The direction in which the fluid flows into the flow channel 50 and is tangent to the flow channel 50 at the second opening end 41b is defined as an eighth tangential direction A8. The angle between the second direction R2 and the eighth tangential direction A8 is defined as an eighth angle θ8. The angle in which the fluid flows into the inlet and is tangent to the inlet of the flow channel 50 and the second direction R2 is defined as a second angle θ2. The second angle θ2 is defined as the average value of the seventh angle θ7 and the eighth angle θ8. The tangential direction of the flow channel 50 at the first opening end 41 a is measured at a position closest to the first opening end 41 a, excluding the chamfered portion of the first opening end 41 a, in the flow channel 50. Similarly, the tangential direction of the flow channel 50 at the second opening end 41 b is measured at a position closest to the second opening end 41 b, excluding the chamfered portion of the second opening end 41 b, in the flow channel 50.

[0035] 5, the second angle θ2 is equal to or greater than 0° and equal to or less than 90°. The second angle θ2 may be equal to or greater than 10°, or may be equal to or greater than 20°. The second angle θ2 may be equal to or less than 80°, or may be equal to or less than 70°.

[0036] (Third embodiment) Next, the configuration of the cutting insert 1 according to the third embodiment will be described. The cutting insert 1 according to the third embodiment differs from the cutting insert 1 according to the first embodiment mainly in that the number of outlets of the flow path 50 is two or more, and other configurations are substantially the same as those of the cutting insert 1 according to the first embodiment. Below, the configurations different from the cutting insert 1 according to the first embodiment will be mainly described.

[0037] Fig. 6 is a perspective schematic view showing the configuration of the cutting insert 1 according to the third embodiment. As shown in Fig. 6, the number of outlets (second openings 42) of the flow path 50 may be two. From another perspective, the second flow path portion 52 may be branched into two from the first flow path portion 51. The fluid outlets may be arranged side by side along a direction perpendicular to the rake face 21. The number of outlets of the flow path 50 is not limited to two. The number of outlets of the flow path 50 may be three, four or more.

[0038] (Fourth embodiment) Next, the configuration 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 flow path 50 has two outlets and the orientation of the outlets is different, but the other configurations are substantially the same as those of the cutting insert 1 according to the first embodiment. The following description will focus on the configurations that differ from the cutting insert 1 according to the first embodiment.

[0039] Fig. 7 is a schematic perspective view showing the configuration of the cutting insert 1 according to the fourth embodiment. Fig. 8 is a schematic cross-sectional view showing the configuration of the cutting insert 1 according to the fourth embodiment. The cross-sectional view shown in Fig. 8 corresponds to the cross-sectional view shown in Fig. 3.

[0040] 7 and 8 , the flow path 50 has a first flow path section 51, a second flow path section 52, and a fourth flow path section 54. The first flow path section 51 has a first opening 41. The first opening 41 is an inlet of the first flow path section 51. The second flow path section 52 has a second opening 42 and a third opening 43. The second opening 42 is an outlet of the second flow path section 52. The second flow path section 52 is connected to the first flow path section 51. The third opening 43 is an inlet of the second flow path section 52 and an outlet of the first flow path section 51.

[0041] The fourth flow path section 54 has a fourth opening 44 and a fifth opening 45. The fourth opening 44 is an outlet of the fourth flow path section 54. The fourth flow path section 54 is connected to the first flow path section 51. The fifth opening 45 is an inlet of the fourth flow path section 54 and an outlet of the first flow path section 51. The fluid passes through the fifth opening 45 and enters the fourth flow path section 54. The direction in which the fluid passes through the fifth opening 45 and enters the fourth flow path section 54 is defined as a fifth flow direction A5. The fifth flow direction A5 is, for example, substantially the same direction as the second direction R2.

[0042] The direction in which the fluid flows out of the fourth opening 44 and the tangential direction of the fourth opening 44 are defined as a fourth flow direction A4. The fourth flow direction A4 is different from the third flow direction A3. When viewed in a direction perpendicular to the rake face 21, the fourth flow direction A4 may intersect with the cutting edge 23. The fourth flow direction A4 may be substantially the same direction as the first flow direction A1. The tangential direction of the fourth opening 44 is measured at a position in the fourth flow path section 54 that is closest to the fourth opening 44, excluding the chamfered portion of the fourth opening 44.

[0043] 8 , the fourth opening 44 is provided in the first region 31 of the protruding wall portion 19. The second opening 42 is provided in the second region 32 of the protruding wall portion 19. In the second direction R2, the fourth opening 44 is located between the front end face 15 and the second opening 42. In the direction from the first side surface 11 toward the second side surface 12, the fifth opening 45 is located between the third opening 43 and the first side surface 11.

[0044] Fig. 9 is a perspective schematic diagram showing the configuration of a rotary cutting tool according to this embodiment. As shown in Fig. 9, the rotary cutting tool according to this embodiment is, for example, a milling cutter. The rotary cutting tool is rotatable around an axis B. The rotary cutting tool mainly has a main body 70, a cutting insert 1, a mounting screw 3, and a position adjustment screw 4. The cutting insert 1 is attached to the main body 70.

[0045] The main body 70 has a first surface 71, a second surface 72, an outer circumferential surface 73, and an inner circumferential surface 74. The first surface 71 is a surface facing a workpiece. The second surface 72 is opposite the first surface 71. The second surface 72 faces the spindle of the machine tool. The outer circumferential surface 73 is continuous with each of the first surface 71 and the second surface 72. In the direction along the axis B, the outer circumferential surface 73 is located between the first surface 71 and the second surface 72. The multiple cutting inserts 1 are arranged at the boundary between the first surface 71 and the outer circumferential surface 73. The multiple cutting inserts 1 are arranged at equal intervals along the rotational direction.

[0046] The cutting insert 1 is attached to the main body 70 using a mounting screw 3. The position adjustment screw 4 adjusts the position of the cutting insert 1 in the direction along the axis B. In the direction along the axis B, the position adjustment screw 4 is between the cutting insert 1 and the second surface 72. A corresponding position adjustment screw 4 is provided for each of the multiple cutting inserts 1.

[0047] FIG. 10 is a schematic front view showing the configuration of the rotary cutting tool according to this embodiment. As shown in FIG. 10 , a third flow path portion 80 is provided in the main body portion 70. A fluid passes through the third flow path portion 80. The third flow path portion 80 extends from the inner circumferential surface 74 of the main body portion 70 toward the outer circumferential surface 73. The third flow path portion 80 has a main body inlet 81 and a main body outlet 82. The main body inlet 81 opens to the inner circumferential surface 74. The main body outlet 82 is located opposite the main body inlet 81. As shown in FIG. 10 , when viewed along the axis B, the third flow path portion 80 extends linearly. A plurality of third flow path portions 80 are provided corresponding to the plurality of cutting inserts 1, respectively.

[0048] Fig. 11 is a cross-sectional schematic view taken along line XI-XI in Fig. 10. The cross-sectional schematic view shown in Fig. 11 is parallel to the axis B and intersects with the outlet and the inlet of the flow path 50 provided in the cutting insert 1. The cross section shown in Fig. 11 includes the center of the second opening 42, which is the outlet of the second flow path portion 52, and the center of the third opening 43, which is the inlet of the second flow path portion 52.

[0049] The third flow direction A3 is a direction in which the fluid flows out from the outlet of the cutting insert 1 and is a tangential direction of the outlet of the flow path 50 of the cutting insert 1. The axial forward direction R3 is parallel to the axis B and is a direction from the second surface 72 toward the first surface 71. The angle formed by the third flow direction A3 and the axial forward direction R3 (hereinafter also referred to as a tenth angle θ10) is greater than 90° and equal to or less than 180°.

[0050] The tenth angle θ10 is substantially the same as the first angle θ1. The tenth angle θ10 may be greater than 100°, greater than 110°, or greater than 120°. The tenth angle θ10 may be equal to or less than 170°, equal to or less than 160°, or equal to or less than 150°.

[0051] Fig. 12 is a schematic cross-sectional view taken along line XII-XII in Fig. 10. The schematic cross-sectional view shown in Fig. 12 is parallel to the axis B and intersects with each of the main body inlet 81 and the main body outlet 82. The cross section shown in Fig. 12 includes the center of the main body inlet 81 and the center of the main body outlet 82.

[0052] When the cutting insert 1 is attached to the body portion 70, the body outlet 82 of the third flow path portion 80 is connected to the flow path 50 of the cutting insert 1. The fluid enters the third flow path portion 80 from the body inlet 81 of the third flow path portion 80 and flows toward the body outlet 82. The fluid that leaves the body outlet 82 enters the first flow path portion 51 provided in the cutting insert 1 from the first opening 41 of the cutting insert 1. The fluid that enters the first flow path portion 51 passes through the second flow path portion 52 and is released to the outside of the cutting insert 1 from the second opening 42.

[0053] As shown in FIG. 12 , in a cross section parallel to the axis B and intersecting the main body inlet 81 and the main body outlet 82, the direction from the main body inlet 81 to the main body outlet 82 is defined as a sixth flow direction A6. The angle between the sixth flow direction A6 and the forward axial direction R3 (hereinafter also referred to as the third angle θ3) is greater than 0° and less than or equal to 90°. When the third flow path section 80 is virtually cut along a plane perpendicular to the sixth flow direction A6, the center of the main body inlet 81 is determined at a cross section closest to the main body inlet 81 among the cross sections where the contour of the third flow path section 80 is continuously continuous. Similarly, when the third flow path section 80 is virtually cut along a plane perpendicular to the sixth flow direction A6, the center of the main body outlet 82 is determined at a cross section closest to the main body outlet 82 among the cross sections where the contour of the third flow path section 80 is continuously continuous. In this specification, the center of the inlet or outlet is defined as the midpoint between two points where the flow path intersects with a straight line in the direction in which the width of the flow path in the cross section is at its maximum when viewed in a direction perpendicular to the cross section.

[0054] The third angle θ3 may be greater than 10°, greater than 20°, or greater than 30°. The third angle θ3 may be equal to or less than 80°, equal to or less than 70°, or equal to or less than 60°.

[0055] Fig. 13 is a cross-sectional schematic diagram showing a state in which a workpiece is cut using a rotary cutting tool. As shown in Fig. 13, the rotary cutting tool 100 is positioned so that a first surface 71 of the rotary cutting tool 100 faces a workpiece 90. The workpiece 90 is, for example, an engine block. A plurality of recesses 92 are formed in a cutting surface 91 of the engine block.

[0056] When flattening a workpiece 90 using the rotary cutting tool 100, a coolant fluid is introduced into the third flow path portion 80 of the main body 70. After passing through the third flow path portion 80 of the main body 70, the coolant enters the flow path 50 of the cutting insert 1 and is discharged to the outside of the cutting insert 1 along the third flow direction A3. Chips of the workpiece 90 cut by the cutting edge 23 move on the rake face 21 and are curled and broken in the third region 33. The broken chips are blown in the third flow direction A3 by the coolant. A portion of the coolant cools the cutting edge 23.

[0057] Although the rotary cutting tool 100 is a milling cutter in the above description, the rotary cutting tool 100 is not limited to a milling cutter. The rotary cutting tool 100 may be, for example, a reamer.

[0058] Next, the effects of the cutting insert 1 and the rotary cutting tool 100 according to this embodiment will be described.

[0059] According to the cutting insert 1 of this embodiment, a vector that is a direction in which the fluid flows out of the outlet and is parallel to the tangential direction of the outlet of the flow path 50 has a component in the first direction R1 that is directed from the front end face 15 to the rear end face 16, and this component is positive. This allows the fluid to be discharged behind the cutting edge 23. As a result, it is possible to reduce the amount of chips that get into the recess 92 provided in the workpiece 90.

[0060] According to the cutting insert 1 of this embodiment, the flow path 50 may have a first flow path portion 51 that forms an inlet and where a fluid accumulates, and a second flow path portion 52 that forms an outlet and is connected to the first flow path portion 51. This makes it possible to reduce the weight of the cutting insert 1. As a result, the rotary cutting tool 100 can be rotated at high speed.

[0061] According to the cutting insert 1 of this embodiment, in a front view of the outlet, the width of the outlet in a direction perpendicular to the rake face 21 may be larger than the width of the outlet in a direction parallel to the rake face 21. This increases the amount of fluid discharged. As a result, it is possible to further reduce the amount of chips entering the recess 92 provided in the workpiece 90.

[0062] According to the cutting insert 1 of this embodiment, in a cross section parallel to the first direction R1 and intersecting the inlet and the outlet, the angle between the tangential direction of the inlet of the flow channel 50, which is the direction in which the fluid flows into the inlet, and the second direction R2, which is the opposite direction to the first direction R1, may be 0° or more and 90° or less, and the angle between the tangential direction of the outlet of the flow channel 50, which is the direction in which the fluid flows out of the outlet, and the second direction R2 may be more than 90° and 180° or less. This allows the fluid to be discharged from the outlet of the flow channel 50 in a region close to the cutting edge 23. As a result, it is possible to further reduce the amount of chips entering the recess 92 provided in the workpiece 90.

[0063] According to the cutting insert 1 according to this embodiment, the second side surface 12 may be provided with a protruding wall portion 19. The outlet may open to the side surface of the protruding wall portion 19. The protruding wall portion 19 can prevent chips from moving forward of the cutting edge 23. As a result, it is possible to further reduce chips from entering the recess 92 provided in the workpiece 90.

[0064] In the rotary cutting tool 100 according to this embodiment, in a cross section parallel to the axis B and intersecting the inlet and the outlet, the angle formed by the direction in which the fluid flows out of the outlet and the tangential direction of the outlet of the flow path 50 and the forward axial direction R3 parallel to the axis B and extending from the second surface 72 to the first surface 71 is greater than 90° and not greater than 180°. This allows the fluid to be discharged in the direction opposite to the direction in which the workpiece 90 is located. As a result, it is possible to reduce the amount of chips entering the recess 92 provided in the workpiece 90.

[0065] According to the rotary cutting tool 100 of this embodiment, in a cross section parallel to the axis B and intersecting each of the main body inlet 81 and the main body outlet 82, the angle formed by the direction from the main body inlet 81 toward the main body outlet 82 and the forward axial direction R3 may be greater than 0° and not greater than 90°. This allows the fluid to be effectively introduced through the third flow path portion 80 of the main body portion 70 to the flow path 50 of the cutting insert 1 attached near the boundary between the outer peripheral surface 73 of the main body portion 70 and the first surface 71.

[0066] The embodiments disclosed herein are illustrative in all respects and should not be considered limiting. The scope of the present invention is defined by the claims, not by the above-described embodiments, and is intended to include meanings equivalent to the claims and all modifications within the scope thereof.

[0067] 1 Cutting insert, 2 Mounting screw arrangement hole, 3 Mounting screw, 4 Position adjustment screw, 10 Base member, 11 First side surface, 12 Second side surface, 13 Third side surface, 14 Fourth side surface, 15 Front end surface, 16 Rear end surface, 19 Protruding wall portion, 20 Cutting edge member, 21 Rake face, 22 Flank face, 23 Cutting edge, 31 First region, 32 Second region, 33 Third region, 34 Fourth region, 41 First opening, 41a First opening end, 41b Second opening end, 42 Second opening, 43 Third opening, 44 Fourth opening, 45 Fifth opening, 50 Flow path, 51 First flow path portion, 52 Second flow path portion, 54 Fourth flow path portion, 70 Main body portion, 71 First surface, 72 Second surface, 73 Outer circumferential surface, 74 Inner circumferential surface, 80 Third flow path portion, 81 Main body inlet, 82 Main body outlet, 90 Work material, 91 Work surface, 92 Dent, 100 Rotary cutting tool, A1 First flow direction, A2 Second flow direction, A3 Third flow direction, A4 Fourth flow direction, A5 Fifth flow direction, A6 Sixth flow direction, A7 Seventh tangential direction, A8 Eighth tangential direction, B Axis, R1 First direction, R2 Second direction, R3 Axis forward, W1 First width, W2 Second width.

Claims

1. A cutting insert for a rotary cutting tool, comprising: a base member; and a cutting edge member attached to the base member, wherein the cutting edge member has a rake face and a flank face continuous with the rake face, and a ridge line between the rake face and the flank face forms a cutting edge, and the base member is provided with a flow path through which a fluid passes, and the base member has a front end face on which the cutting edge member is disposed, a rear end face opposite the front end face, a first side face between the front end face and the rear end face and on which an inlet of the flow path is provided, and a second side face opposite the first side face and on which an outlet of the flow path is provided, wherein the rear end face is flat, and the first side face is flat, and an imaginary plane along the rear end face and an imaginary plane along the first side face are perpendicular, a vector in a direction in which the fluid flows out of the outlet and which is parallel to a tangent direction of the outlet of the flow path is perpendicular to the rear end surface and has a component in a first direction from the front end surface toward the rear end surface, the component being positive.

2. A cutting insert as described in claim 1, wherein the flow path has a first flow path portion that forms the inlet and in which the fluid accumulates, and a second flow path portion that forms the outlet and is connected to the first flow path portion.

3. A cutting insert according to claim 1 or claim 2, wherein, in a front view of the outlet, the width of the outlet in a direction perpendicular to the cutting surface is greater than the width of the outlet in a direction parallel to the cutting surface.

4. A cutting insert according to any one of claims 1 to 3, wherein in a cross section parallel to the first direction and intersecting each of the inlet and the outlet, an angle formed between a direction in which the fluid flows into the inlet and a tangential direction of the inlet of the flow path and a second direction opposite to the first direction is between 0° and 90°, and an angle formed between a direction in which the fluid flows out of the outlet and a tangential direction of the outlet of the flow path and the second direction is between 90° and 180°.

5. The cutting insert according to claim 2, wherein, in a front view of the outlet, the width of the outlet in a direction perpendicular to the cutting face is larger than the width of the outlet in a direction parallel to the cutting face; and in a cross section parallel to the first direction and intersecting each of the inlet and the outlet, an angle formed between a tangential direction of the inlet of the flow path, which is a direction in which the fluid flows into the inlet, and a second direction, which is the opposite direction to the first direction, is between 0° and 90°, and an angle formed between a tangential direction of the outlet of the flow path, which is a direction in which the fluid flows out of the outlet, and the second direction is between 90° and 180°.

6. A cutting insert according to any one of claims 1 to 5, wherein the second side surface is provided with a protruding wall portion, and the outlet opens into the side surface of the protruding wall portion.

7. The cutting insert according to any one of claims 1 to 6, wherein the number of outlets is two or more.

8. A rotary cutting tool rotatable around an axis, comprising: a cutting insert; and a body portion to which the cutting insert is attached, wherein the cutting insert includes: a base member; and a cutting edge member attached to the base member, wherein the cutting edge member has a rake face and a flank face continuous with the rake face, and a ridge line between the rake face and the flank face forms a cutting edge, wherein the base member is provided with a flow path through which a fluid passes, and wherein the base member has a front end face on which the cutting edge member is disposed, a rear end face opposite the front end face, a first side face between the front end face and the rear end face and on which an inlet of the flow path is provided, and a second side face opposite the first side face and on which an outlet of the flow path is provided, wherein the body portion has a first face facing a workpiece and a second face opposite the first face, a direction in which the fluid flows out of the outlet and which is tangential to the outlet of the flow path, and an axial forward direction parallel to the axis and extending from the second surface to the first surface, the angle formed by the direction in which the fluid flows out of the outlet and which is tangential to the outlet of the flow path, is greater than 90° and is not greater than 180°.

9. A rotary cutting tool as described in claim 8, wherein the main body portion is provided with a third flow path portion through which the fluid passes, the third flow path portion having a main body outlet connected to the flow path and a main body inlet opposite the main body outlet, and in a cross section parallel to the axis and intersecting each of the main body inlet and the main body outlet, the angle formed by the direction from the main body inlet toward the main body outlet and the forward direction of the axis is greater than 0° and not more than 90°.

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