Cutting tool, method for manufacturing cutting tool, and method for manufacturing cutting article

Abstract

The invention provides a cutting tool, a method for manufacturing the cutting tool, and a method for manufacturing a cutting material. A cutting tool (10) is provided with: a tool body (12) that rotates relative to a workpiece about an axis (A); a cutting edge (22) formed at the tip of the tool body; a mounting seat (24) formed by cutting a rake face (18) adjacent to the cutting edge into a concave shape; a cutter (14) embedded in the mount and engaged with the tool body; a first positioning portion (36) having a first engagement portion (34) formed on a side surface of the cutter, and a first locking portion (30) formed on a step portion (28) of the mount and fitted with the first engagement portion; and a second positioning portion (40) having a second engagement portion (38) formed on a side surface of the cutter at a position different from that of the first positioning portion, and a second locking portion (32) formed on the stepped portion of the mount and fitted with the second engagement portion. Therefore, the cost can be reduced.

Description

Technical Field

[0001] The present invention relates to a cutting tool for cutting a workpiece by rotating relative to the workpiece about an axis, a method for manufacturing the cutting tool, and a method for manufacturing a cutting piece (chip). Background Art

[0002] Among tools such as drills that rotate around an axis, there are known cutting tools (also called edged tools) in which a cutting piece made of a hard material is mounted on the top of the tool body. In such cutting tools, in order to break the chips and improve the discharge of the chips, a concave-convex structure called a chip breaker is sometimes provided on the front face of the cutting piece (for example, International Publication No. 2022 / 209460). Summary of the invention

[0003] The cutting tool described in International Publication No. 2022 / 209460 is manufactured by forming a concave mounting seat on the front cutting edge of the top of the tool body, and arranging a cutting piece on the mounting seat and joining them by brazing or other methods. In the manufacturing method of the prior art, it is easy to cause positional offset between the cutting piece and the tool body. Therefore, a structure that requires high positional accuracy, such as a chip breaker, is formed by precision machining after joining the cutting piece to the tool body. However, such a manufacturing method requires more processing time and has the problem of poor production efficiency.

[0004] The purpose of the present invention is to solve the above technical problems.

[0005] A technical solution disclosed below is a cutting tool, comprising: a tool body, which rotates relative to a workpiece around an axis; a cutting edge, which is formed at the top of the tool body; a mounting seat, which is formed by cutting the front cutting surface of the cutting edge into a concave shape; a cutting piece, which is arranged on the mounting seat and engaged with the tool body; a first positioning portion, which has a first engaging portion and a first stopping portion, wherein the first engaging portion is formed on the side surface of the cutting piece, and the first stopping portion is formed on the step portion of the mounting seat to stop the first engaging portion; and a second positioning portion, which has a second engaging portion and a second stopping portion, wherein the second engaging portion is formed on the side surface of the cutting piece at a different position from the first engaging portion, and the second stopping portion is formed on the step portion of the mounting seat to stop the second engaging portion.

[0006] Another technical solution is a method for manufacturing a cutting tool, the cutting tool comprising: a tool body, which rotates relative to a workpiece around an axis; a cutting edge, which is formed at the top of the tool body; a mounting seat, which is formed by cutting the front cutting surface of the cutting edge into a concave shape; a cutting piece, which is arranged on the mounting seat and engaged with the tool body; a first positioning portion, which has a first engaging portion and a first stopping portion, wherein the first engaging portion is formed on the side of the cutting piece, and the first stopping portion is formed on the step portion of the mounting seat to stop the first engaging portion; and a second positioning portion, which has a second engaging portion and a second stopping portion, wherein the second engaging portion is formed on the side of the cutting piece. The side surface of the cutting piece is different from the first locking portion, and the second locking portion is formed on the step portion of the mounting seat to lock the second locking portion. The manufacturing method of the cutting tool includes: a process of preparing the cutting piece having the first locking portion and the second locking portion; a process of preparing the mounting seat formed with the tool body having the first locking portion and the second locking portion; a positioning process of positioning the cutting piece on the mounting seat by locking the first locking portion to the first locking portion and locking the second locking portion to the second locking portion; and a joining process of brazing the cutting piece positioned on the mounting seat to the tool body.

[0007] Another technical solution is a method for manufacturing a cutting piece for a cutting tool, wherein the cutting tool comprises: a tool body, which rotates relative to a workpiece around an axis; a cutting edge, which is formed at the top of the tool body; a mounting seat, which is formed by cutting the front cutting surface of the cutting edge into a concave shape; a cutting piece, which is arranged on the mounting seat and engaged with the tool body; a first positioning portion, which has a first engaging portion and a first stopping portion, wherein the first engaging portion is formed on the side of the cutting piece, and the first stopping portion is formed on the step portion of the mounting seat to stop the first engaging portion; a second positioning portion, which has a second engaging portion and a second stopping portion, wherein the second engaging portion is formed on the cutting piece. The side surface of the cutting piece is different from the first engaging portion, the second engaging portion is formed on the step portion of the mounting seat to engage the second engaging portion; and a chip breaker groove is formed on the surface of the cutting piece and crushes the chips. The manufacturing method of the cutting piece includes: a process of preparing a thin plate-shaped cutting piece base material having a plurality of cutting piece forming areas formed with the cutting piece; a chip breaker groove forming process of forming the chip breaker groove for crushing the chips by respectively forming concave and convex structures in the cutting piece forming areas of the cutting piece base material; and a cutting process of forming the cutting piece by cutting the cutting piece forming area while forming the first engaging portion and the second engaging portion after the chip breaker groove forming process.

[0008] The cutting tool, the method for manufacturing the cutting tool, and the method for manufacturing the cutting piece of the above-mentioned technical solution can form a concave-convex structure on the cutting piece before it is joined to the tool body, thereby improving production efficiency compared with the prior art.

[0009] The above-mentioned objects, features and advantages will be easily understood through the following description of the embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a perspective view of the cutting tool involved in the first embodiment.

[0011] Figure 2 yes Figure 1 An enlarged stereoscopic view of the top of the cutting tool.

[0012] Figure 3 yes Figure 1 Front view of the top surface of the cutting tool.

[0013] Figure 4 This is a perspective view of the tip of the cutting tool in a state where no cutting tool is attached.

[0014] Figure 5 It is an explanatory diagram of the manufacturing method of the cutting tool involved in the first embodiment.

[0015] Fig. 6A It is a top view of the cutting piece base material. Figure 6B It means formed in Fig. 6A A top view of the chip breaker groove and the cutting piece forming area of ​​the cutting piece base material. Figure 6C is from Figure 6B A top view of the cutting piece cut from the cutting piece base material.

[0016] Figure 7 This is an explanatory diagram showing an example of positioning of the cutting tool and the tool body when the curvature radius of the curved portion of the step portion is larger than the curvature radius of the corner portion of the cutting tool.

[0017] Figure 8 It is a side view of the cutting tool involved in the second embodiment. DETAILED DESCRIPTION

[0018] (First Embodiment) Figure 1 to Figure 3The cutting tool 10 involved in the present embodiment shown is a drill that cuts a workpiece (not shown) by rotating in a rotation direction B1 with an axis A (axis center) as the center. In addition, the cutting tool 10 can also be fixed to a fixture, and the workpiece can be cut by rotating it in a rotation direction B2 with the axis A as the center. This cutting tool 10 is used for hole processing of a workpiece. In this specification, the direction orthogonal to the axis A is called radial. The direction close to the axis A in the radial direction is the inner side, and the direction away from the axis A is the outer side. Arrows A0 and A1 are directions parallel to the axis A, and the end located in the direction shown by the arrow A0 is called the top end, and the end located in the direction shown by the arrow A1 is called the base end.

[0019] The cutting tool 10 has a tool body 12 and a cutting piece 14. The tool body 12 has a cylindrical rod-shaped shank 12a and a main body 12b located at the top of the shank 12a. The main body 12b has a plurality of grooves 16 on the outer periphery. The grooves 16 discharge chips generated by cutting. A plurality of grooves 16 are provided at predetermined intervals in the circumferential direction centered on the axis A. Figure 1 The tool body 12 shown has two grooves 16 arranged at intervals of 180° from each other. The grooves 16 extend parallel to the axis A. However, the extending direction of the grooves 16 is not limited to being parallel to the axis A, and the grooves 16 may also be in a twisted shape inclined at a predetermined angle relative to the direction of the axis A.

[0020] The groove 16 is formed in a V-shape or an L-shape in a cross section of the tool body 12 cut perpendicularly to the axis A. The groove 16 has a first inner surface 16a and a second inner surface 16b. The first inner surface 16a is located near the rotation direction B2, and the second inner surface 16b is located near the rotation direction B1. Figure 3 As shown, the first inner surface 16 a forms a rake face 18 at the tip of the cutting tool 10 .

[0021] The tool body 12 has a back cutting face 20 at its top end. The back cutting face 20 constitutes at least a portion of the top end surface 12d of the tool body 12. The back cutting face 20 may also be perpendicular to the axis A. In addition, the back cutting face 20 may also be formed along a conical surface inclined relative to the axis A. The back cutting face 20 forms a sharp cutting edge 22 on the ridgeline intersecting with the front cutting face 18. The cutting edge 22 extends from the vicinity of the axis A to the outer periphery of the tool body 12. Figure 2 In the example of, the cutting edge 22 extends in a straight line in the radial direction. In addition, the direction of the cutting edge 22 is not limited to the radial direction. In addition, the cutting edge 22 is not limited to a straight line, and can also extend along a curve.

[0022] like Figure 4As shown, the cutting tool 10 of the present embodiment has a mounting seat 24 near the cutting edge 22. The mounting seat 24 is formed by cutting the first inner surface 16a of the tool body 12 into a concave shape. The cutting piece 14 is mounted on the mounting seat 24. The mounting seat 24 has a planar bottom surface 26 and a step portion 28 formed between the bottom surface 26 and the front cutting edge 18. The bottom surface 26 is formed as a surface parallel to the front cutting edge 18. The height of the step portion 28 (the distance between the bottom surface 26 and the front cutting edge 18 in a direction perpendicular to the front cutting edge 18) is substantially the same as the thickness of the cutting piece 14.

[0023] The step portion 28 includes a first straight portion 28a, a second straight portion 28b, a curved portion 28c, a first locking portion 30, and a second locking portion 32. The first straight portion 28a extends in a straight line parallel to or substantially parallel to the direction of the axis A. The second straight portion 28b extends in a direction intersecting the first straight portion 28a. Figure 4 In the example shown, the extending direction of the second straight portion 28b is parallel to the radial direction of the tool body 12, but the present invention is not limited thereto. The curved portion 28c is a portion that connects the first straight portion 28a and the second straight portion 28b with a smooth curve. The curved portion 28c may be a curved arc that is curved in a concave shape. The curved portion 28c disperses the local load of the mounting seat 24 and prevents the cutting tool 14 from peeling off.

[0024] The first locking portion 30 is formed on the first straight portion 28a. The first locking portion 30 is formed at a portion corresponding to a first engaging portion 34 of the cutting tool 14 described later, and is used to lock the first engaging portion 34. The first locking portion 30 and the first engaging portion 34 together constitute a first positioning portion 36. Figure 4 In the example shown, the first locking portion 30 is formed as a recessed portion recessed relative to the first straight portion 28a. However, the first locking portion 30 is not limited thereto, and may be a convex portion protruding from the first straight portion 28a.

[0025] The second stopper 32 is formed on the second straight portion 28b. The second stopper 32 is formed at a portion corresponding to the second engaging portion 38 of the cutting member 14 described later, and is used to engage the second engaging portion 38. The second stopper 32 and the second engaging portion 38 together constitute the second positioning portion 40. The second stopper 32 is formed as a recessed portion recessed relative to the second straight portion 28b. However, the second locking portion 32 is not limited thereto, and may also be a convex portion protruding from the second straight portion 28b.

[0026] like Figure 2 As shown in FIG. 1 , the cutting tool 14 is arranged on the mounting seat 24 and is engaged with the tool body 12. That is, the cutting tool 14 is embedded in the mounting seat 24. Figure 2In the example shown, the cutting edge 22A of the cutting piece 14 constitutes the cutting edge 22 together with the tool body 12. In addition, the entire cutting edge 22 of the cutting tool 10 may be constituted by only the cutting edge 22A of the cutting piece 14. The cutting piece 14 is formed of a harder material than the material constituting the tool body 12 (for example, tool steel or high-speed steel), so that the life of the cutting tool 10 can be extended. The cutting piece 14 is located in the tool body 12 near the outer periphery where the relative speed with the workpiece increases, and bears most of the cutting of the workpiece.

[0027] like Figure 4 As shown, the cutting tool 14 is in the shape of a thin plate, and has a cutting tool joint surface 14a, a cutting tool surface 14b, a cutting tool top end surface 14c, a cutting tool outer peripheral surface 14d, a first side surface 14e, a second side surface 14f, and a corner 14g as main outer surfaces. The cutting tool joint surface 14a is a surface that abuts and joins with the bottom surface 26 of the mounting seat 24. The cutting tool surface 14b is located on the opposite side of the cutting tool joint surface 14a, and constitutes the rake face 18A of the cutting tool 14.

[0028] like Figure 2 As shown, the cutting piece surface 14b is connected to the first inner surface 16a of the tool body 12 without any height difference, forming the same plane. That is, the cutting piece surface 14b is coplanar with the first inner surface 16a of the tool body 12. The cutting piece surface 14b and the first inner surface 16a of the tool body 12 together form the front cutting face 18 of the cutting tool 10. The cutting piece 14 of this embodiment has a chip breaker groove 42 formed by a concave-convex structure on the cutting piece surface 14b. The chip breaker groove 42 crushes the chips of the workpiece generated at the cutting edge 22A, thereby improving the chip discharge. The details of the chip breaker groove 42 are described, for example, in International Publication No. 2022 / 209460.

[0029] The cutting tool top end face 14c is located at the top end of the cutting tool 14. The cutting tool top end face 14c is formed to be coplanar with the top end face 12d of the tool body 12 by grinding or the like, and constitutes the flank face 20 of the cutting tool 10. The cutting edge 22A of the cutting tool 14 is formed at the intersection of the cutting tool top end face 14c and the cutting tool surface 14b.

[0030] like Figure 2 As shown, the cutter outer peripheral surface 14d is exposed to the outer periphery of the cutting tool 10 when the cutter 14 is joined to the mounting seat 24. The cutter outer peripheral surface 14d is connected to the outer peripheral surface 12c of the tool body 12 without any height difference by grinding or the like, and is formed into a curved surface having the same curvature as the outer peripheral surface 12c.

[0031] The first side surface 14e is in contact with the first straight portion 28a of the mounting seat 24. The first side surface 14e extends in a straight line. The second side surface 14f extends in a straight line in a direction intersecting the first side surface 14e and is in contact with the second straight portion 28b of the mounting seat 24. The corner portion 14g connects the first side surface 14e and the second side surface 14f with a smooth curved surface. The corner portion 14g prevents stress concentration of the cutting piece 14 and thus prevents damage to the cutting piece 14. The radius of curvature of the corner portion 14g may be the same as or different from the radius of curvature of the curved portion 28c.

[0032] Furthermore, if the curvature radius of the curved portion 28c and the corner portion 14g is extremely small, it becomes easy to position the cutting tool 14. However, when the curvature radius is set to an extremely small radius, the load during cutting is locally concentrated on the corner portion 14g and the curved portion 28c, which may cause wear and other problems and may cause peeling of the cutting tool 14. Therefore, the curvature radius of the curved portion 28c and the corner portion 14g is preferably 0.1 mm or more, for example.

[0033] The cutting member 14 of the present embodiment also has a first engaging portion 34 and a second engaging portion 38. The first engaging portion 34 is a protrusion formed by protruding from the first side surface 14e. The first engaging portion 34 is engaged with the first stop portion 30 formed as a recessed portion in the first straight portion 28a of the mounting seat 24. In addition, the first engaging portion 34 can also be a recessed portion recessed from the first side surface 14e. In this case, the first engaging portion 34 is engaged with the first stop portion 30 formed as a convex portion in the first straight portion 28a of the mounting seat 24. The first engaging portion 34 and the first stop portion 30 together constitute a first positioning portion 36. The first positioning portion 36 prevents the displacement of the cutting member 14 in the direction along the first side surface 14e and the first straight portion 28a. In one example, the first positioning portion 36 positions the cutting member 14 in the axial direction.

[0034] The second engaging portion 38 is a protrusion formed by protruding from the second side surface 14f, and engages with the second stopper 32 formed as a recessed portion in the second straight portion 28b of the mounting seat 24. In addition, the second engaging portion 38 can also be a recessed portion recessed from the second side surface 14f. In this case, the second engaging portion 38 is engaged with the second stopper 32 formed as a convex portion in the second straight portion 28b of the mounting seat 24. The second engaging portion 38 and the second stopper 32 together constitute the second positioning portion 40. The second positioning portion 40 prevents the displacement of the cutting member 14 in the direction along the second side surface 14f and the second straight portion 28b. In one example, the second positioning portion 40 performs radial positioning of the cutting member 14.

[0035] The cutting tool 10 as described above is Figure 3The cutting tool 10 is used to cut a workpiece by rotating in the direction of arrow B. A cutting piece 14 disposed at the tip of the cutting tool 10 comes into contact with the surface of the workpiece to cut the workpiece, thereby forming a hole of a predetermined size in the workpiece.

[0036] Next, a method for manufacturing the cutting tool 10 according to the present embodiment will be described.

[0037] like Figure 5 As shown, the manufacturing method of the cutting tool 10 includes a machining step (S10 to S30) of the tool body 12, a manufacturing step (S40 to S60) of the cutting piece 14, a joining step (S70, S80) of the cutting piece 14 and the tool body 12, and a finishing step (S90 to S100). Each step will be described below in the above order.

[0038] The processing steps of the tool body 12 are as follows: Figure 5 The outer diameter grinding process (S10) of the tool body 12 is started. First, the tool body 12 is prepared. The tool body 12 has a structure in which a rod-shaped main body 12b made of a hard metal material such as tool steel is joined to a rod-shaped shank 12a (see Figure 1 ). Next, the tool body 12 is ground into a cylindrical rod shape. Through this process (step S10), the outer peripheral surface 12c is formed, thereby forming the cylindrical rod-shaped tool body 12 extending in the axial direction.

[0039] Next, the processing step of the tool body 12 enters Figure 5 In the groove processing step (S20), the outer peripheral surface 12c of the tool body 12 is engraved by grinding to form the groove 16 (see Figure 1 ). In this step (S20), if Figure 1 As in the example shown in FIG. 1 , a plurality of grooves 16 are formed in a circumferential direction of the tool body 12 .

[0040] Next, the processing step of the tool body 12 enters Figure 5 The mounting seat processing step (S30) is a grinding process using a grinding wheel tool. In the mounting seat processing step (S30), the first inner surface 16a of the groove 16 is ground to form the mounting seat 24. Through this process, a mounting seat having Figure 4 The step portion 28 and the mounting seat 24 of the bottom surface 26 are shown. In addition, the step portion 28 is formed with a first straight portion 28a, a second straight portion 28b, a curved portion 28c, a first locking portion 30, and a second locking portion 32. Thus, the processing step of the tool body 12 is completed.

[0041] Next, the manufacturing process of the cutting tool 14 will be described. The manufacturing process of the cutting tool 14 starts with a cutting tool base material preparation process (S40). The cutting tool base material 44 is, for example, Fig. 6A A thin plate-shaped substrate as shown. The cutting piece base material 44 has a thickness of several hundred μm to several mm. The cutting piece base material 44 has an area capable of forming multiple cutting pieces 14 at the same time, and multiple cutting piece forming areas 46 are set on its surface 44a. The materials used for the cutting piece base material 44 include, for example, sintered diamond (PCD), cubic boron nitride (CBN), ceramics, metal ceramics or tungsten carbide alloys. The surface 44a of the cutting piece base material 44 later becomes the cutting piece surface 14b. The back side 44b of the cutting piece base material 44 later becomes the cutting piece joint surface 14a.

[0042] Next, the manufacturing process of the cutting tool 14 enters the chip breaker forming process (S50). In the chip breaker forming process (S50), as shown in FIG. Figure 6B As shown, the cutting piece surface 14b is engraved on each cutting piece forming area 46 of the cutting piece base material 44. Through this process, a chip breaker 42 including a plurality of groove-shaped concave-convex structures is formed. This process is performed, for example, by laser processing. Since this process forms the chip breaker 42 for a plurality of cutting piece forming areas 46 at the same time, there is no need to perform processes such as positioning processes and cutting piece conveying processes for individual cutting pieces 14, and the chip breaker 42 can be efficiently formed.

[0043] Then, if Figure 5 As shown, the manufacturing process of the cutting piece 14 enters the cutting piece cutting process (S60). In the cutting piece cutting process (S60), the cutting Figure 6B Each cutting piece forming area 46 of the cutting piece base material 44 shown in the figure is processed by cutting the cutting piece 14 from the cutting piece base material 44. The cutting piece cutting step (S60) is performed by laser processing, for example. Figure 6C As shown, the cutting piece 14 having the chip breaker groove 42 on the cutting piece surface 14b is completed. In this process, the first engaging portion 34 and the second engaging portion 38 are formed at the predetermined position of the cutting piece 14. Thus, the manufacturing process of the cutting piece 14 is completed. The implementation of the manufacturing process of the cutting piece 14 can be independent of the processing of the tool body 12.

[0044] Next, the process of joining the cutting tool 14 and the tool body 12 will be described. Figure 5 The cutting piece installation process (S70) shown in FIG. 1 starts. In the cutting piece installation process (S70), as shown in FIG. Figure 7As shown, the cutting tool 14 is arranged on the mounting seat 24 of the tool body 12, and the cutting tool 14 is positioned relative to the tool body 12. When the curvature radius of the curved portion 28c of the mounting seat 24 is larger than the curvature radius of the corner portion 14g of the cutting tool 14, as shown in FIG. Figure 7 As shown, the cutting piece 14 is rotated and displaced around the contact portion T between the corner portion 14g of the cutting piece 14 and the curved portion 28c, and the cutting piece 14 is easily tilted. Therefore, in the cutting piece 14 and the mounting seat 24 without the first positioning portion 36 and the second positioning portion 40, the cutting piece 14 shakes in the mounting seat 24, and there is a possibility of positional deviation and angular deviation.

[0045] In contrast, in the cutting tool 14 and the tool body 12 of the present embodiment, the first engaging portion 34 of the cutting tool 14 is engaged with the first locking portion 30 of the mounting seat 24 in the first positioning portion 36. In addition, in the second positioning portion 40, the second engaging portion 38 of the cutting tool 14 is engaged with the second locking portion 32 of the mounting seat 24. The cutting tool 14 is accurately positioned on the mounting seat 24 without shaking due to the first positioning portion 36 and the second positioning portion 40. Since the depth of the mounting seat 24 is the same as the thickness of the cutting tool 14, the cutting tool surface 14b of the cutting tool 14 disposed on the mounting seat 24 forms the same plane as the first inner surface 16a of the tool body 12.

[0046] After that, the process of joining the cutting tool 14 and the tool body 12 is carried out. Figure 5 The brazing process (step S80) shown in FIG. 1 is performed. In the brazing process (S80), the cutting piece 14 positioned on the mounting seat 24 is joined to the tool body 12 by brazing. In the present embodiment, since the cutting piece surface 14b and the first inner surface 16a are coplanar, the inclination and floating of the cutting piece 14 during brazing can be easily found. Thus, the joining process of the cutting piece 14 and the tool body 12 is completed.

[0047] Next, the tool body 12 joined with the cutting tool 14 is subjected to a finishing process. Figure 5 As shown in FIG. 1 , the finishing process includes a finishing process of the top peripheral surface (S90). In the finishing process of the top peripheral surface (S90), the outer peripheral surface 12c of the tool body 12 and the outer peripheral surface 14d of the cutting piece are ground. Figure 2 As shown, the cutter outer peripheral surface 14d is formed so as to be continuous with the outer peripheral surface 12c of the tool body 12 without any unevenness.

[0048] Finishing process includes Figure 5 The flank machining step (S100) is a step of grinding the top end face 14c of the cutting piece and the top end face 12d of the tool body 12 to form the flank face 20 of the cutting tool 10. Figure 2As shown, the flank face 20 is formed so that the top end face 14c of the cutting piece is connected to the top end face 12d of the tool body 12 without any height difference. Figure 2 ) intersect to form sharp cutting edges 22, 22A (see Figure 2 ).also, Figure 5 The order of the back face processing step (S100) and the top peripheral surface finishing step (S90) can also be the same as Figure 5 The order shown is reversed. Through the above steps, the cutting tool 10 according to the embodiment is completed.

[0049] In the manufacturing method of the prior art, since the cutting piece 14 is tilted and offset, it is necessary to form the chip breaker 42 while adjusting the position and the concave and convex surface in accordance with the tilt and position offset of the cutting piece 14, which results in a time-consuming manufacturing of the chip breaker 42. In addition, since the processing of the tool body 12 and the formation of the chip breaker 42 on the cutting piece surface 14b cannot be performed simultaneously, the manufacturing of one cutting tool takes time and the manufacturing cost becomes high.

[0050] In contrast, the manufacturing method of the cutting tool 10 of the present embodiment can join the cutting piece 14 to the tool body 12 with good position accuracy, so that the chip breaker 42 can be formed on the cutting piece 14 before joining with the tool body 12. Accordingly, the formation of the chip breaker 42 can be separated from the processing of the tool body 12 and performed simultaneously, so that the time required for manufacturing the cutting tool 10 can be greatly shortened, thereby reducing the manufacturing cost. In addition, the chip breaker 42 of multiple cutting pieces 14 can be formed at the same time, so that the manufacturing cost of the chip breaker 42 can be effectively reduced.

[0051] (Second Embodiment) Figure 8 The cutting tool 10A of the present embodiment shown is a step reamer. Figure 1 to Figure 3 The same components of the cutting tool 10 described above are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0052] The cutting tool 10A has a tool body 12A with cutting edges formed at the top and the periphery. The tool body 12A has a step portion 48 whose diameter changes at a predetermined position in the axial direction. The tool body 12A is formed with a plurality of grooves 16A extending in a spiral shape inclined relative to the axial direction. In the example shown in the figure, each groove 16A forms the end portion of the top side with the top surface 12d or the step portion 48. The groove 16A may not be divided by the step portion 48, or may be formed across the step portion 48 in the axial direction.

[0053] A mounting seat 24 for mounting the cutting tool 14 is formed near the top of each groove 16A. In this embodiment, the cutting tool 14 is respectively arranged in the adjacent portion of the top surface 12d and the adjacent portion of each step portion 48. Each cutting tool 14 is inserted into the mounting seat 24 and joined by brazing. The mounting seat 24 and the cutting tool 14 are as shown in FIG. Figure 1 to Figure 3 As described.

[0054] The cutting tool 10A of this embodiment fixes the cutting piece 14 to the tool body 12A with high positioning accuracy, so that the chip breaker groove 42 can be formed on the cutting piece 14 before it is joined to the tool body 12A. Accordingly, the formation of the chip breaker groove 42 can be performed separately from the processing of the tool body 12A, so the time required for manufacturing the cutting tool 10A can be greatly shortened, thereby reducing the manufacturing cost.

[0055] In connection with the above disclosure, the following notes are also disclosed.

[0056] (Note 1) The above disclosed technical solution is a cutting tool (10, 10A), comprising: a tool body (12, 12A) which rotates relative to a workpiece around an axis; a cutting edge (22, 22A) which is formed at the top of the tool body; a mounting seat (24) which is formed by cutting the front cutting surface (18, 18A) of the cutting edge into a concave shape; a cutting piece (14) which is arranged on the mounting seat and engaged with the tool body; a first positioning portion (36) which has a first engaging portion (34) and a first stopping portion (30 ), wherein the first engaging portion (34) is formed on the side surface of the cutting piece, and the first stopping portion (30) is formed on the step portion (28, 48) of the mounting seat to stop the first engaging portion; and a second positioning portion (40), which has a second engaging portion (38) and a second stopping portion (32), wherein the second engaging portion (38) is formed on the side surface of the cutting piece at a different position from the first engaging portion, and the second stopping portion (32) is formed on the step portion of the mounting seat to stop the second engaging portion.

[0057] The cutting tool can join the cutting piece to the tool body with good position accuracy, so that a chip breaker groove can be formed on the cutting piece before joining with the tool body. Accordingly, the formation of the chip breaker groove can be separated from the processing of the tool body, so the time required for manufacturing the cutting tool can be greatly shortened, thereby reducing the manufacturing cost.

[0058] (Note 2) According to the cutting tool described in Note 1, the first positioning portion may position the cutting piece relative to the tool body in the axial direction, and the second positioning portion may position the cutting piece relative to the tool body in the radial direction. The cutting tool can suppress errors when the cutting piece is joined to the tool body, thereby joining the cutting piece to the correct position.

[0059] (Note 3) According to the cutting tool described in Note 1 or 2, the step portion may include: a first straight portion (28a) intersecting the cutting edge; a second straight portion (28b) extending in a direction intersecting the first straight portion; and a curved portion (28c) connecting the first straight portion and the second straight portion with a curved surface, the first stopper being located at the first straight portion, and the second stopper being located at the second straight portion. The cutting tool can form the first stopper and the second stopper at the same time as the grinding process of the mounting seat, so the productivity is excellent.

[0060] (Note 4) According to the cutting tool described in Note 3, the cutting piece may have a first side surface (14e) abutting against the first straight portion, a second side surface (14f) abutting against the second straight portion, and a corner portion (14g) connecting the first side surface and the second side surface by a curved surface, the first engaging portion is located on the first side surface, and the second engaging portion is located on the second side surface. The cutting tool can form the first engaging portion and the second engaging portion of the cutting piece while performing the cutting piece cutting process, so the productivity is excellent.

[0061] (Note 5) The cutting tool according to any one of Notes 1 to 4 may be such that the thickness of the cutting piece is equal to the height of the mounting seat, and the cutting piece surface (14b) of the cutting piece is coplanar with the rake face of the tool body. The cutting tool can easily detect the inclination or lifting of the cutting piece when the cutting piece is engaged.

[0062] (Note 6) The cutting tool according to any one of Supplementary Notes 1 to 5 may be such that the cutting piece has a chip breaker (42) on a cutting piece surface (14b) for breaking up chips. The cutting tool can efficiently form the chip breaker.

[0063] (Note 7) Another technical solution disclosed above is a method for manufacturing a cutting tool, wherein the cutting tool comprises: a tool body, which rotates relative to a workpiece around an axis; a cutting edge, which is formed at the top end of the tool body; a mounting seat, which is formed by cutting the front cutting surface of the cutting edge into a concave shape; a cutting piece, which is arranged on the mounting seat and engaged with the tool body; a first positioning portion, which comprises a first engaging portion and a first stopping portion, wherein the first engaging portion is formed on a side surface of the cutting piece, and the first stopping portion is formed on a step portion of the mounting seat to stop the first engaging portion; and a second positioning portion, which comprises a second engaging portion and a second stopping portion, wherein the second engaging portion is formed on the side surface of the cutting piece, and the first stopping portion is formed on a step portion of the mounting seat to stop the first engaging portion. The second locking portion is formed on the step portion of the mounting seat to lock the second locking portion, and the manufacturing method of the cutting tool includes: a process of preparing the cutting piece having the first locking portion and the second locking portion; a process of preparing the mounting seat having the first locking portion and the second locking portion; a positioning process of positioning the cutting piece on the mounting seat by locking the first locking portion and the second locking portion by locking the second locking portion; and a joining process of brazing the cutting piece positioned on the mounting seat to the tool body.

[0064] In the above-described method for manufacturing a cutting tool, since the cutting piece can be joined to the tool body with good positional accuracy, the time required for manufacturing the cutting tool can be significantly shortened, thereby reducing the manufacturing cost.

[0065] (Note 8) The manufacturing method of the cutting tool according to Note 7 may also include a chip breaker forming step, in which a chip breaker for breaking chips is formed on the front cutting edge of the cutting piece, and the chip breaker forming step is performed before the positioning step. The manufacturing method of the cutting tool can form a chip breaker on the cutting piece before it is joined to the tool body. Accordingly, the time required for manufacturing the cutting tool can be greatly shortened, thereby reducing the manufacturing cost.

[0066] (Note 9) Another technical solution disclosed above is a method for manufacturing a cutting piece for a cutting tool, wherein the cutting tool comprises: a tool body, which rotates relative to a workpiece around an axis; a cutting edge, which is formed at the top end of the tool body; a mounting seat, which is formed by cutting the front cutting surface of the cutting edge into a concave shape; a cutting piece, which is arranged on the mounting seat and engaged with the tool body; a first positioning portion, which comprises a first engaging portion and a first stopping portion, wherein the first engaging portion is formed on the side surface of the cutting piece, and the first stopping portion is formed on the step portion of the mounting seat to stop the first engaging portion; a second positioning portion, which comprises a second engaging portion and a second stopping portion, wherein the second engaging portion is formed on the side of the cutting piece that is engaged with the first positioning portion The side surfaces of different parts of the positioning portion, the second locking portion is formed on the step portion of the mounting seat to lock the second locking portion; and a chip breaker groove is formed on the cutting piece surface of the cutting piece for crushing chips. The manufacturing method of the cutting piece includes: a process of preparing a thin plate-shaped cutting piece base material (44) having a plurality of cutting piece forming areas (46) formed with the cutting piece; a chip breaker groove forming process of forming the chip breaker groove for crushing chips by forming a concave-convex structure in each forming area of ​​the cutting piece forming area of ​​the cutting piece base material; and a cutting piece cutting process of forming the cutting piece by cutting the cutting piece forming area while forming the first locking portion and the second locking portion after the chip breaker groove forming process.

[0067] The manufacturing method of the cutting tool can form a plurality of cutting tool chip breaker grooves on the surface of a cutting tool base material at the same time, thereby reducing the time required for machining the cutting tool and thus reducing the manufacturing cost of the cutting tool.

[0068] In addition, the present invention is not limited to the above disclosure, and various structures can be adopted without departing from the gist of the present invention.

Claims

1. A cutting tool, characterized in that: have: A tool body that rotates relative to the workpiece about an axis; a cutting edge formed at a top end of the tool body; A mounting seat formed by cutting the rake face of the cutting edge into a concave shape; a cutting element, which is disposed on the mounting seat and engaged with the tool body; A first positioning portion having a first engaging portion and a first stopping portion, wherein the first engaging portion is formed on a side surface of the cutting piece, and the first stopping portion is formed on a step portion of the mounting seat to stop the first engaging portion; and a second positioning portion, which has a second engaging portion and a second stopping portion, wherein the second engaging portion is formed on a side surface of the cutting piece at a different location from the first engaging portion, and the second stopping portion is formed on the step portion of the mounting seat to stop the second engaging portion.

2. The cutting tool according to claim 1, characterized in that The first positioning portion positions the cutting tool in the axial direction relative to the tool body, and the second positioning portion positions the cutting tool in the radial direction relative to the tool body.

3. The cutting tool according to claim 1, characterized in that The step portion has: a first straight portion intersecting with the cutting edge; a second straight line portion extending in a direction intersecting the first straight line portion; and a curved portion connecting the first straight portion and the second straight portion with a curved surface, The first locking portion is located on the first straight portion, and the second locking portion is located on the second straight portion.

4. The cutting tool according to claim 3, characterized in that The cutting tool has a first side surface abutting against the first straight portion, a second side surface abutting against the second straight portion, and a corner portion connecting the first side surface and the second side surface by a curved surface. The first engaging portion is located on the first side surface, and the second engaging portion is located on the second side surface.

5. The cutting tool according to claim 1, characterized in that The thickness of the cutting element is the same as the height of the mounting seat, and the cutting element surface of the cutting element is coplanar with the rake face of the tool body.

6. The cutting tool according to any one of claims 1 to 5, characterized in that: The cutting piece has a chip breaking groove on the surface of the cutting piece for breaking chips.

7. A method for manufacturing a cutting tool, the cutting tool comprising: a tool body that rotates relative to a workpiece about an axis; a cutting edge formed at the top of the tool body; a mounting seat formed by cutting a front cutting surface of the cutting edge into a concave shape; a cutting piece that is arranged on the mounting seat and engaged with the tool body; a first positioning portion that has a first engaging portion and a first stopping portion, wherein: The first engaging portion is formed on the side surface of the cutting piece, and the first stopping portion is formed on the step portion of the mounting seat to stop the first engaging portion; and the second positioning portion has a second engaging portion and a second stopping portion, wherein the second engaging portion is formed on the side surface of the cutting piece at a different position from the first positioning portion, and the second stopping portion is formed on the step portion of the mounting seat to engage with the second engaging portion. The invention is characterized by comprising: a step of preparing the cutting tool having the first engaging portion and the second engaging portion; A step of preparing the tool body formed with the mounting seat having the first locking portion and the second locking portion; a step of positioning the cutting tool on the mounting seat by causing the first engaging portion to be locked by the first locking portion and causing the second engaging portion to be locked by the second locking portion; and A joining step of brazing the cutting tool positioned on the mounting seat to the tool body.

8. The method for manufacturing a cutting tool according to claim 7, characterized in that: The method comprises a chip breaker groove forming step of forming a chip breaker groove for breaking chips on the rake face of the cutting piece, and the chip breaker groove forming step is performed before the positioning step.

9. A method for manufacturing a cutting piece for a cutting tool, the cutting tool comprising: A tool body that rotates relative to a workpiece about an axis; a cutting edge formed at the top of the tool body; a mounting seat formed by cutting the rake face of the cutting edge into a concave shape; a cutting piece that is arranged on the mounting seat and engaged with the tool body; a first positioning portion having a first engaging portion and a first stopping portion, wherein: The first engaging portion is formed on the side of the cutting piece, and the first stopping portion is formed on the step portion of the mounting seat to stop the first engaging portion; the second positioning portion has a second engaging portion and a second stopping portion, wherein the second engaging portion is formed on the side of the cutting piece at a different position from the first positioning portion, and the second stopping portion is formed on the step portion of the mounting seat to stop the second engaging portion; and a chip breaker groove, It is formed on the cutting surface of the cutting piece and is used to break up the chips. The invention is characterized by comprising: a step of preparing a thin plate-shaped cutting tool base material having a plurality of cutting tool forming regions on which the cutting tools are formed; A chip breaker forming step of forming the chip breaker groove for breaking chips by forming a concavo-convex structure in each forming area of ​​the cutting tool forming area of ​​the cutting tool base material; and After the chip breaker forming step, a cutting tool cutting step is performed to form the cutting tool by cutting the cutting tool forming region while forming the first engaging portion and the second engaging portion.

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