Cutting tool, and method for manufacturing cut workpiece

Abstract

The objective of the present invention is to reduce the risk of an increase in the manufacturing cost of a cutting tool, even if the cutting tool is provided with a sensor. The sensor is positioned on an outer surface on a tip end side of a holder. A wiring member is electrically connected to the sensor and extends from the sensor side toward a rear end of the holder. The holder includes a groove that opens in both a lower surface and a second side surface, and that extends from the tip end side toward the rear end. The wire member is positioned within the groove.

Description

Cutting tool and method for manufacturing machined product

[0001] The present disclosure relates to a cutting tool used for cutting a workpiece and a method for manufacturing a machined product.

[0002] A known cutting tool used in cutting a workpiece to manufacture a machined product is, for example, the cutting tool described in Patent Document 1. The cutting tool described in Patent Document 1 includes a rod-shaped holder (referred to as a main body in Patent Document 1), a sensor unit for detecting a physical quantity (referred to as physical information in Patent Document 1) of a cutting insert (referred to as a cutting blade in Patent Document 1), and a wiring member (referred to as a cable member in Patent Document 1) electrically connected to the sensor unit. In the cutting tool described in Patent Document 1, the wiring member is built into the holder.

[0003] Japanese Patent Publication No. 2012-020359

[0004] A cutting tool according to the present disclosure includes a holder, a cutting insert, a sensor, and a wiring member. The holder has a rod shape extending from a front end to a rear end, and has a front end surface located on the front end side, an upper surface extending from the front end surface toward the rear end, a lower surface located opposite the upper surface, a first side surface located between the upper and lower surfaces and extending from the front end surface toward the rear end, a second side surface located opposite the first side surface, and a pocket opening to the front end surface, the upper surface, and the first side surface. The cutting insert is located in the pocket and has a cutting edge. The sensor is located on an outer surface of the holder on the front end side and detects a physical quantity of the holder. The wiring member is electrically connected to the sensor and extends from the sensor side toward the rear end. The holder further has a groove opening to both the lower surface and the second side surface and extending from the front end side toward the rear end. The wiring member is located in the groove.

[0005] 5 is a schematic perspective view of a cutting tool according to an embodiment of the present disclosure. FIG. 6 is a schematic perspective view of the cutting tool shown in FIG. 1, viewed from another angle. FIG. 7 is a schematic plan view of the cutting tool shown in FIG. 1. FIG. 8 is a schematic view of the cutting tool shown in FIG. 1, viewed from the tip side. FIG. 9 is a schematic side view of the cutting tool shown in FIG. 1. FIG. 10 is a schematic enlarged view of another side of the cutting tool shown in FIG. 5. FIG. 6 is a cross-sectional view taken along line VII-VII in FIG. 5. FIG. 7 is a cross-sectional view taken along line VIII-VIII in FIG. 5. FIG. 8 is a cross-sectional view taken along line IX-IX in FIG. 5. FIG. 9 is an enlarged view of portion X in FIG. 8, showing a groove in a holder and a wiring member. FIG. 10 is an enlarged cross-sectional view of a groove in a holder and a wiring member in a cutting tool according to another aspect of an embodiment of the present disclosure. FIG. 11 is an enlarged cross-sectional view of a groove in a holder and a wiring member in a cutting tool according to another aspect of an embodiment of the present disclosure. FIG. 12 is an enlarged cross-sectional view of a groove in a holder and a wiring member in a cutting tool according to another aspect of an embodiment of the present disclosure. FIG. 13 is a schematic view illustrating a method for manufacturing a machined product according to an embodiment of the present disclosure. FIG. 14 is a schematic view illustrating a method for manufacturing a machined product according to an embodiment of the present disclosure.

[0006] In the cutting tool described in Patent Document 1, in order to incorporate the wiring member into the holder, it is necessary to form a through hole in the holder to accommodate the wiring member. However, it is not easy to form a long, thin through hole along the central axis of the rod-shaped holder, and there is a concern that this will increase the manufacturing cost of the cutting tool. In other words, if the cutting tool described in Patent Document 1 is provided with a sensor unit, there is a concern that this will increase the manufacturing cost of the cutting tool.

[0007] According to the present disclosure, even when a cutting tool is equipped with a sensor, it is possible to reduce the risk of an increase in the manufacturing cost of the cutting tool.

[0008] Hereinafter, a cutting tool and a method for manufacturing a machined product according to an embodiment of the present disclosure will be described in detail with reference to the drawings. However, for the sake of convenience, the drawings referred to below show only the components necessary for explaining the embodiment in a simplified form. Therefore, a cutting insert according to an embodiment of the present disclosure may include any components not shown in the drawings referred to. The dimensions of the components in the drawings do not faithfully represent the actual dimensions of the components and the dimensional ratios of each member.

[0009] Furthermore, in this disclosure, the description will be based on an orthogonal coordinate system XYZ defined by three mutually orthogonal directions. The X direction refers to the front-to-rear direction, with one side of the X direction being the front side or forward direction, and the other side of the X direction being the rear side or backward direction. The Y direction refers to the left-to-right direction, with one side of the Y direction being the left side or leftward direction, and the other side of the Y direction being the right side or rightward direction. The Z direction refers to the up-down direction, with one side of the Z direction being the upper side or upward direction, and the other side of the Z direction being the lower side or downward direction. The XY direction refers to the two directions of the X direction and the Y direction, the XZ direction refers to the two directions of the X direction and the Z direction, and the YZ direction refers to the two directions of the Y direction and the Z direction. The XYZ direction refers to the three directions of the X direction, the Y direction, and the Z direction.

[0010] In the drawings, "FF" indicates the forward direction, "FR" indicates the rearward direction, "L" indicates the leftward direction, "R" indicates the rightward direction, "U" indicates the upward direction, and "D" indicates the downward direction.

[0011] <Cutting Tool> A cutting tool 10 according to an embodiment of the present disclosure will be described with reference to FIGS. 1 to 13 . FIG. 1 is a schematic perspective view of the cutting tool 10 according to an embodiment of the present disclosure. FIG. 2 is a schematic perspective view of the cutting tool shown in FIG. 1 as viewed from another angle. FIG. 3 is a schematic plan view of the cutting tool 10 shown in FIG. 1. FIG. 4 is a schematic view of the cutting tool 10 shown in FIG. 1 as viewed from the tip side. FIG. 5 is a schematic side view of the cutting tool 10 shown in FIG. 1. FIG. 6 is an enlarged side view of the vicinity of the sensor unit as viewed from the opposite side to FIG. 5. FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. 5. FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 5. FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. 5. FIG. 10 is an enlarged view of portion X in FIG. 8 , showing the groove in the holder and the wiring member. FIGS. 11 to 13 are enlarged cross-sectional views showing the groove in the holder and the wiring member in cutting tools according to other aspects of the embodiment of the present disclosure.

[0012] 1 to 3 , a cutting tool 10 according to an embodiment of the present disclosure is a tool used for cutting a workpiece W (see FIG. 14 ). Cutting of the workpiece W includes external diameter machining, internal diameter machining, grooving, cut-off, and the like. The cutting tool 10 may also include a holder 14 attached to a tool rest 12 of a lathe, a cutting insert 16 held by the holder 14, a clamp 18 that fixes the cutting insert 16 to the holder 14, and a clamp screw 20 that attaches the clamp 18 to the holder 14.

[0013] 1 to 3, the holder 14 may be rod-shaped and extend in the X direction from the front end 14a to the rear end 14b. The longitudinal direction of the holder 14 may be the X direction. The holder 14 may have a main body 14m in the shape of a square pillar located closer to the rear end 14b than the clamp 18.

[0014] 1 to 5 , the holder 14 may have a leading end surface 22 located on the leading end 14 a side and a trailing end surface 24 located opposite the leading end surface 22. The holder 14 may have an upper surface 26 extending in the X direction from the leading end surface 22 toward the trailing end 14 b to the trailing end surface 24. The holder 14 may have a lower surface 28 located opposite the upper surface 26, and the lower surface 28 may extend in the X direction from the leading end surface 22 toward the trailing end 14 b to the trailing end surface 24.

[0015] The holder 14 may have a first side surface 30 located between the upper surface 26 and the lower surface 28, and the first side surface 30 may extend in the X direction from the tip surface 22 toward the rear end 14b to the rear end surface 24. The first side surface 30 of the holder 14 may be connected to the upper surface 26 and the lower surface 28. In the main body portion 14m of the holder 14, the first side surface 30 may be perpendicular to the lower surface 28 and the upper surface 26.

[0016] The holder 14 may have a second side surface 32 located opposite the first side surface 30, and the second side surface 32 may extend in the X direction from the tip surface 22 toward the rear end 14b to the rear end surface 24. The second side surface 32 may be connected to the upper surface 26 and the lower surface 28. In the main body portion 14m, the second side surface 32 may be perpendicular to the lower surface 28 and the upper surface 26.

[0017] The front end surface 22, the rear end surface 24, the upper surface 26, the lower surface 28, the first side surface 30, and the second side surface 32 of the holder 14 may form an outer surface of the holder 14. The holder 14 may also have a pocket 34 on the front end 14a side for holding the cutting insert 16. The pocket 34 may be open to the front end surface 22, the upper surface 26, and the first side surface 30.

[0018] When the cutting tool 10 is attached to the tool rest 12, a lower surface 28 of the main body 14m of the holder 14 is supported by the mounting surface 12a (see FIG. 8) of the tool rest 12. A second side surface 32 of the main body 14m of the holder 14 is supported by the inner wall surface 12b (see FIG. 8) of the tool rest 12. An upper surface 26 of the main body 14m of the holder 14 is pressed by the fixing screw 12c (see FIG. 8) of the tool rest 12.

[0019] Examples of materials for the holder 14 include metals such as stainless steel, carbon steel, cast iron, and aluminum alloys. The length of the holder 14 may be set to, for example, 100 mm to 400 mm.

[0020] As shown in the example in FIGS. 1 to 5 , the cutting insert 16 may be positioned in a pocket 34 of the holder 14. The cutting insert 16 may be a replaceable insert known as a throw-away insert. The cutting insert 16 may have a rectangular plate shape, or may have a shape other than a rectangular plate shape, such as a triangular or pentagonal plate shape. The cutting insert 16 may have a first insert surface 36, a second insert surface 38 located opposite the first insert surface 36, and a plurality of insert side surfaces 40 located between the first insert surface 36 and the second insert surface 38.

[0021] The cutting insert 16 may have a cutting edge 42 at the intersection of the first insert surface 36 and the insert side surface 40. The first insert surface 36 may function as a rake surface for chip flow. The insert side surface 40 may function as a clearance surface.

[0022] The cutting insert 16 may have a through hole 44 that opens to the first insert surface 36 and the second insert surface 38. The cutting insert 16 is attached to the pocket 34 by tightening the clamp screw 20 with the tip of the clamp 18 engaged with the through hole 44.

[0023] Examples of materials for the cutting insert 16 include cemented carbide and cermet. Examples of cemented carbide compositions include WC-Co, WC-TiC-Co, and WC-TiC-TaC-Co. WC-Co is produced by adding cobalt (Co) powder to tungsten carbide (WC) and sintering the mixture. WC-TiC-Co is produced by adding titanium carbide (TiC) to WC-Co. WC-TiC-TaC-Co is produced by adding tantalum carbide (TaC) to WC-TiC-Co. Cermets are sintered composite materials in which a ceramic component is combined with a metal. Specifically, examples of cermets include those primarily composed of titanium compounds such as titanium carbide (TiC) and titanium nitride (TiN).

[0024] The surface of the cutting insert 16 may be coated with a film by chemical vapor deposition (CVD) or physical vapor deposition (PVD). The material of the film may be, for example, titanium carbide (TiC), titanium nitride (TiN), titanium carbonitride (TiCN), or alumina (Al ２ O ３ ) etc.

[0025] As shown in the examples of FIGS. 2 to 7 , the cutting tool 10 may include a sensor unit 46 for detecting physical quantities such as acceleration, vibration, strain, or internal stress of the holder 14 (cutting tool 10). The sensor unit 46 may be located on the tip 14a side of the holder 14, from the lower surface 28 to the second side surface 32 of the main body 14m. The unit base 48 may be attached to the main body 14m of the holder 14 with an adhesive. The unit base 48 may be attached to the main body 14m of the holder 14 by the magnetic force of a built-in magnet. Alternatively, the unit base 48 may be attached to the main body 14m of the holder 14 with a fixing member such as a screw. Examples of materials for the unit base 48 include synthetic resin and metal.

[0026] 4 and 7 , the unit base 48 may be L-shaped in a cross section perpendicular to the X direction, which is the longitudinal direction of the holder 14. The unit base 48 may have a first portion 48a located on the lower surface 28 of the holder 14 and a second portion 48b located on the second side surface 32 of the holder 14.

[0027] As shown in the examples in FIGS. 6 and 7 , the first portion 48a of the unit base 48 may have a first recess 50 that opens toward the lower surface 28 of the holder 14. The first recess 50 of the unit base 48 may be a bottomed hole (recess) or a through hole. The second portion 48b of the unit base 48 may have a second recess 52 that opens toward the second side surface 32 of the holder 14. The second recess 52 of the unit base 48 may be a bottomed hole or a through hole. The second portion 48b of the unit base 48 may have a third recess 54 that opens toward the second side surface 32 of the holder 14. The third recess 54 of the unit base 48 may be a bottomed hole or a through hole. The third recess 54 of the unit base 48 may be continuous with the second recess 52.

[0028] The sensor unit 46 may have a first sensor 56 located in a first recess 50 of the unit base 48. The first sensor 56 may be fixed in the first recess 50 of the unit base 48 with an adhesive or the like. The first sensor 56 may abut against the lower surface 28 of the holder 14. The first sensor 56 may be located on the lower surface 28, which is the outer surface, on the side of the tip 14a of the holder 14. The first sensor 56 may detect one or more physical quantities of the holder 14, such as acceleration, vibration, strain, or internal stress. The detection direction of the first sensor 56 may be the Y direction. In other words, the first sensor 56 may detect physical quantities of the holder 14 in the Y direction, such as acceleration, vibration, strain, or internal stress. The first sensor 56 may detect acceleration of the holder 14 corresponding to a feed force, which is one of the cutting loads.

[0029] The sensor unit 46 may have a second sensor 58 located in the second recess 52 of the unit base 48. The second sensor 58 may be fixed in the second recess 52 of the unit base 48 with an adhesive or the like. The second sensor 58 may abut against the second side surface 32 of the holder 14. The second sensor 58 may be located on the second side surface 32, which is the outer surface of the holder 14, on the side of the tip 14a of the holder 14. The second sensor 58 may detect one or more physical quantities, such as acceleration, vibration, strain, or internal stress of the holder 14. The second sensor 58 may detect the same physical quantities as the first sensor 56. The detection direction of the second sensor 58 may be the X direction, which is perpendicular to the detection direction of the first sensor 56. In other words, the second sensor 58 may detect physical quantities, such as acceleration, vibration, strain, or internal stress of the holder 14 in the X direction. The second sensor 58 may detect acceleration of the holder 14, which corresponds to a thrust force, which is a cutting load.

[0030] The sensor unit 46 may have a third sensor 60 located in the third recess 54 of the unit base 48. The third sensor 60 may be fixed in the third recess 54 of the unit base 48 with an adhesive or the like. The third sensor 60 may abut against the second side surface 32 of the holder 14. The third sensor 60 may be located on the second side surface 32 on the side of the tip 14a of the holder 14. The third sensor 60 may detect one or more physical quantities, such as acceleration, vibration, strain, or internal stress of the holder 14. The third sensor 60 may detect the same physical quantities as the first sensor 56 and the second sensor 58. The detection direction of the third sensor 60 may be the Z direction perpendicular to the detection direction of the first sensor 56 and the second sensor 58. In other words, the third sensor 60 may detect physical quantities, such as acceleration, vibration, strain, or internal stress of the holder 14 in the Z direction. The third sensor 60 may detect the acceleration of the holder 14 corresponding to a principal component force, which is one of the cutting loads.

[0031] The first sensor 56, the second sensor 58, and the third sensor 60 may detect physical quantities such as acceleration, vibration, distortion, or internal stress of the holder 14 in the X, Y, and Z directions. The first sensor 56, the second sensor 58, and the third sensor 60 may detect acceleration of the holder 14 corresponding to cutting loads in three directions (principal force, thrust force, and feed force).

[0032] The positions of the first sensor 56, the second sensor 58, and the third sensor 60 in the X direction may be the same. The first sensor 56, the second sensor 58, and the third sensor 60 may be capacitance detection type sensors or piezoresistive type sensors. If the first sensor 56, the second sensor 58, and the third sensor 60 are capacitance detection type sensors, the sensors may be MEMS (Micro Electro Mechanical Systems).

[0033] The detection direction of the first sensor 56 may be changed from the Y direction to the X and Y directions. The first sensor 56 may detect physical quantities such as acceleration, vibration, distortion, or internal stress of the holder 14 in the X and Y directions. The first sensor 56 may detect acceleration, etc. of the holder 14 corresponding to the feed force and the principal force. In these cases, either the second sensor 58 or the third sensor 60 may be omitted from the components of the sensor unit 46. The first sensor 56 and the second sensor 58, or the first sensor 56 and the third sensor 60, may detect physical quantities such as acceleration, vibration, distortion, or internal stress of the holder 14 in the X, Y, and Z directions. The first sensor 56 and the second sensor 58, or the first sensor 56 and the third sensor 60, may detect acceleration, etc. of the holder 14 corresponding to the cutting load in three directions.

[0034] The detection direction of the second sensor 58 may be changed from the X direction to the XZ directions. The second sensor 58 may detect physical quantities such as acceleration, vibration, distortion, or internal stress of the holder 14 in the XZ directions. The second sensor 58 may detect acceleration, etc. of the holder 14 corresponding to the thrust force and the principal force. In this case, the third sensor 60 may be omitted from the components of the sensor unit 46. The first sensor 56 and the second sensor 58 may detect physical quantities such as acceleration, vibration, distortion, or internal stress of the holder 14 in the X, Y, and Z directions. The first sensor 56 and the second sensor 58 may detect acceleration, etc. of the holder 14 corresponding to the cutting load in three directions.

[0035] The detection direction of the third sensor 60 may be changed from the Z direction to the XZ direction. The third sensor 60 may detect physical quantities such as acceleration, vibration, distortion, or internal stress of the holder 14 in the XZ directions. The third sensor 60 may detect acceleration, etc. of the holder 14 corresponding to the principal force and thrust force. In this case, the second sensor 58 may be omitted from the components of the sensor unit 46. The first sensor 56 and the third sensor 60 may detect physical quantities such as acceleration, vibration, distortion, or internal stress of the holder 14 in the X, Y, and Z directions. The first sensor 56 and the third sensor 60 may detect acceleration, etc. of the holder 14 corresponding to the cutting load in three directions.

[0036] 2 , 5 , 6 , 8 , and 9 , the cutting tool 10 may include a wiring member 62 electrically connected to the first sensor 56, the second sensor 58, and the third sensor 60. The wiring member 62 may extend in the X direction from the first sensor 56 side toward the rear end 14 b of the holder 14.

[0037] As shown in the examples in Figures 2, 5, 6, and 9 to 13, the holder 14 may have a groove 64 that opens to both the lower surface 28 and the second side surface 32. When the groove 64 opens to both the lower surface 28 and the second side surface 32, it is easier to form the groove 64 than when it opens to only one of the lower surface 28 and the second side surface 32. Furthermore, as will be described later, when the wiring member 62 is positioned in the groove 64, it is easier to attach the wiring member 62. The groove 64 of the holder 14 may open to the rear end surface 24. The groove 64 of the holder 14 may extend in the X direction from the front end 14a toward the rear end 14b. The groove 64 of the holder 14 may have a first seating surface 66 connected to the second side surface 32 and a second seating surface 68 connected to the lower surface 28.

[0038] 10 , in a cross section perpendicular to the X direction, which is the longitudinal direction of the holder 14, the width J of the groove 64 in a direction parallel to the second side surface 32 may be larger than the width K of the groove in a direction parallel to the lower surface 28. Also, as in the examples shown in FIGS. 2 and 3 , the groove 64 of the holder 14 may be located closer to the rear end 14b of the holder 14 than the pocket 34. The groove 64 of the holder 14 may be located closer to the second side surface 32 than the pocket 34.

[0039] 2 , 6 , and 9 to 13 , the wiring member 62 may be positioned in the groove 64 of the holder 14. In other words, the groove 64 of the holder 14 may accommodate the wiring member 62. The wiring member 62 may be electrically connected to the first sensor 56, the second sensor 58, and the third sensor 60. The wiring member 62 may extend in the X direction from the first sensor 56 side toward the rear end 14 b of the holder 14.

[0040] 9 to 13 , the wiring member 62 may have a wiring conductor 70 electrically connected to the first sensor 56, the second sensor 58, and the third sensor 60. The wiring conductor 70 may extend in the X direction from the first sensor 56 side toward the rear end 14b of the holder 14.

[0041] The wiring member 62 may have a cylindrical holding member 72 that holds the wiring conductor 70. The holding member 72 may be positioned in the groove 64 of the holder 14. In other words, the groove 64 of the holder 14 may accommodate the holding member 72. The holding member 72 may extend in the X direction from the front end 14a of the holder 14 toward the rear end 14b. The material of the holding member 72 may be the same as that of the holder 14. If the material of the holding member 72 is metal, the holding member 72 may be divided along the X direction. The material of the holding member 72 may be synthetic resin, and the holding member 72 may be an extrusion molded product.

[0042] 10 to 13 , the holding member 72 may have a first end surface 74 located on the side of the lower surface 28 of the holder 14 and a second end surface 76 located on the side of the second side surface 32 of the holder 14. The distance in the Z direction from the upper surface 26 of the holder 14 to the first end surface 74 of the holding member 72 may be equal to or less than the distance in the Z direction from the upper surface 26 to the lower surface 28 of the holder 14. The distance in the Y direction from the first side surface 30 of the holder 14 to the second end surface 76 of the holding member 72 may be equal to or less than the distance in the Y direction from the first side surface 30 to the second side surface 32 of the holder 14.

[0043] The retaining member 72 may have a first abutment surface 78 located opposite the first end surface 74, and the first abutment surface 78 may abut against the first seating surface 66 of the groove 64 of the holder 14. The retaining member 72 may have a second abutment surface 80 located opposite the second end surface 76, and the second abutment surface 80 may abut against the second seating surface 68 of the groove 64 of the holder 14.

[0044] 11 , the first abutment surface 78 of the holding member 72 and the first seating surface 66 of the groove 64 of the holder 14 may be inclined with respect to an imaginary plane VF parallel to the lower surface 28 so as to move away from the lower surface 28 with increasing distance from the second side surface 32 of the holder 14. Also, as in the example shown in FIG. 12 , the second abutment surface 80 of the holding member 72 and the second seating surface 68 of the groove 64 of the holder 14 may be inclined with respect to an imaginary plane VP perpendicular to the lower surface 28 so as to move away from the second side surface 32 with increasing distance from the lower surface 28 of the holder 14.

[0045] 13 , the first seating surface 66 and the second seating surface 68 of the groove 64 of the holder 14 may each be flat. The groove 64 of the holder 14 may further have a connecting surface 82 in the shape of a concave curved surface located between the first seating surface 66 and the second seating surface 68. The wiring member 62 may be spaced apart from the connecting surface 82 of the groove 64 of the holder 14.

[0046] The wiring member 62 may be electrically connected to an information processing device installed outside the machine tool, etc. The information processing device may be configured by a computer, and may have a memory that stores various control programs, etc., and a CPU (Central Processing Unit) that interprets and executes the control programs.

[0047] The control program is executed by the CPU, causing the information processing device to perform various functions. In one aspect, the information processing device may adjust the movement speed of the cutting tool 10 based on the physical quantities of the holder 14 detected by the first sensor 56, the second sensor 58, and the third sensor 60. In another aspect, the information processing device may adjust the rotation speed of the workpiece W based on the physical quantities of the holder 14 detected by the first sensor 56, the second sensor 58, and the third sensor 60.

[0048] According to the exemplary embodiment of the present disclosure, the groove 64 of the holder 14 is open to both the lower surface 28 and the second side surface 32 and extends in the X direction from the side of the first sensor 56, etc. toward the rear end 14b of the holder 14. Therefore, the groove 64 can be easily machined in the holder 14 using a milling tool such as an end mill having a width larger than the groove width of the groove 64. As a result, according to the exemplary embodiment of the present disclosure, even when the cutting tool 10 is equipped with the sensor unit 46, the risk of an increase in the manufacturing cost of the cutting tool 10 can be reduced. If the groove 64 of the holder 14 is open only to one of the lower surface 28 and the second side surface 32, the groove 64 must be machined in the holder 14 using a milling tool with a small diameter having a shape corresponding to the groove width of the groove 64.

[0049] Furthermore, when the wiring member 62 has a cylindrical holding member 72, it is possible to reduce play of the wiring member 62 within the groove 64 of the holder 14. As a result, according to the example embodiment of the present disclosure, it is possible to avoid damage to the wiring member 62.

[0050] According to the example embodiment of the present disclosure, as described above, the distance in the Z direction from the upper surface 26 of the holder 14 to the first end surface 74 of the holding member 72 is equal to or less than the distance in the Z direction from the upper surface 26 to the lower surface 28 of the holder 14. Furthermore, the distance in the Y direction from the first side surface 30 of the holder 14 to the second end surface 76 of the holding member 72 is equal to or less than the distance in the Y direction from the first side surface 30 to the second side surface 32 of the holder 14. In such a case, the wiring member 62 is less likely to protrude from the outer surface of the holder 14. As a result, according to the example embodiment of the present disclosure, the cutting tool 10 is more likely to be stably fixed to the tool post 12.

[0051] 11 , when the first abutment surface 78 of the holding member 72 and the first seat surface 66 of the groove 64 of the holder 14 are inclined with respect to the imaginary plane VF, the wiring member 62 is less likely to protrude from the outer surface of the holder 14. As a result, according to the example of the embodiment of the present disclosure, the cutting tool 10 is more likely to be stably fixed to the tool post 12.

[0052] 12 , when the second abutment surface 80 of the holding member 72 and the second seat surface 68 of the groove 64 of the holder 14 are inclined with respect to the imaginary plane VP, the wiring member 62 is less likely to protrude from the outer surface of the holder 14. As a result, according to the example of the embodiment of the present disclosure, the cutting tool 10 is more likely to be stably fixed to the tool post 12.

[0053] 10 to 13 , when the first abutment surface 78 and the second abutment surface 80 of the holding member 72 abut against the first seating surface 66 and the second seating surface 68 of the groove 64 of the holder 14, respectively, it is easy to position the wiring member 62 relative to the holder 14. This makes it easy to attach the cutting tool 10 to the tool post 12 according to the exemplary embodiment of the present disclosure.

[0054] 10 , in a cross section perpendicular to the X direction, when the width K of the groove 64 in a direction parallel to the second side surface 32 is larger than the width J of the groove in a direction parallel to the lower surface 28, the rigidity of the holder 14 is likely to be ensured even if the groove 64 is machined in the holder 14. As a result, according to the example embodiment of the present disclosure, the durability of the cutting tool 10 can be increased even when the cutting tool 10 is equipped with the sensor unit 46.

[0055] 2 and 3 , when the groove 64 of the holder 14 is located closer to the rear end 14b of the holder 14 than the pocket 34, the principal component of force is less likely to be transmitted to the groove 64 of the holder 14. This prevents stress from concentrating at the boundary between the first bearing surface 66 and the second bearing surface 68 in the groove 64 of the holder 14, reducing deformation of this boundary. Furthermore, cracks are less likely to occur at the boundary. As a result, according to the exemplary embodiment of the present disclosure, the durability of the cutting tool 10 can be improved even when the cutting tool 10 includes the sensor unit 46.

[0056] 2 and 3 , when the groove 64 of the holder 14 is located closer to the second side surface 32 than the pocket 34, the principal component of force is less likely to be transmitted to the groove 64 of the holder 14. This prevents stress from concentrating at the boundary between the first bearing surface 66 and the second bearing surface 68 in the groove 64 of the holder 14, reducing deformation of this boundary. Furthermore, cracks are less likely to occur at the boundary. As a result, according to the exemplary embodiment of the present disclosure, the durability of the cutting tool 10 can be improved even when the cutting tool 10 includes the sensor unit 46.

[0057] 13 , when a concavely curved connecting surface 82 is located between the first and second bearing surfaces 66 and 68 in the groove 64 of the holder 14, stress concentration at the connecting surface 82, which is the boundary between the first and second bearing surfaces 66 and 68 in the groove 64 of the holder 14, is avoided, reducing deformation of this boundary. Furthermore, cracks are less likely to occur at the boundary. Thus, according to the exemplary embodiment of the present disclosure, the durability of the cutting tool 10 can be improved even when the cutting tool 10 includes a sensor unit 46.

[0058] In particular, when the wiring member 62 is separated from the connection surface 82 of the groove 64 of the holder 14, even if stress is concentrated on the connection surface 82, the connection surface 82 can be intentionally deformed slightly, making it less likely that cracks will occur on the connection surface 82 of the holder 14. As a result, according to the example embodiment of the present disclosure, the durability of the cutting tool 10 can be further improved even when the cutting tool 10 is equipped with the sensor unit 46.

[0059] When the groove 64 of the holder 14 is open to the rear end surface 24, the wiring member 62 can be pulled out from the rear end 14b of the holder 14. Therefore, according to the example embodiment of the present disclosure, the wiring member 62 is less likely to become an obstacle, and the cutting tool 10 can be easily attached to the tool post 12.

[0060] <Method for manufacturing machined product> A method for manufacturing a machined product according to an embodiment of the present disclosure will be described with reference to Fig. 14 to Fig. 16. Fig. 14 to Fig. 16 are schematic views illustrating a method for manufacturing a machined product according to an embodiment of the present disclosure.

[0061] As shown in the examples of FIGS. 14 to 16 , the method for manufacturing a machined product according to an embodiment of the present disclosure is a method for manufacturing a machined product M, which is a workpiece W that has been machined, and includes a first step, a second step, and a third step. The first step is a step of rotating the workpiece W around its axis S. The second step is a step of bringing the cutting insert 16 of the cutting tool 10 into contact with the rotating workpiece W to cut the workpiece W. The third step is a step of separating the cutting tool 10 from the cut workpiece W. Examples of materials for the workpiece W include stainless steel, carbon steel, alloy steel, cast iron, and non-ferrous metals. The specific details of the method for manufacturing a machined product according to the embodiment are as follows.

[0062] First, the cutting tool 10 is attached to the tool rest 12, and the workpiece W is attached to the chuck of the lathe. Next, as shown in the example of Fig. 14, the chuck is rotated to rotate the workpiece W about its axis S (first step). Then, as shown in the example of Fig. 15, the cutting tool 10 is moved in the direction of arrow D1 to approach the workpiece W, and the cutting insert 16 is brought into contact with the rotating workpiece W, thereby cutting the workpiece W (second step). This allows a machined surface Wf to be formed on the workpiece W.

[0063] 16, the cutting tool 10 is then moved in the direction of arrow D2 to separate the cutting tool 10 from the workpiece W (third step). This completes the cutting of the workpiece W, and a machined product M can be produced, which is the machined workpiece W. Because the cutting tool 10 has excellent cutting ability for the reasons described above, it is possible to produce a machined product M with excellent machining precision.

[0064] To continue cutting, the cutting insert 16 may be repeatedly brought into contact with different locations on the workpiece W while the workpiece W is being rotated. In the embodiment of the present disclosure, the cutting tool 10 is brought close to the workpiece W, but since it is sufficient that the cutting tool 10 and the workpiece W are relatively close to each other, the workpiece W may also be brought close to the cutting tool 10. In this regard, the cutting tool 10 is moved away from the workpiece W in the same manner.

[0065] In one embodiment, (1) a cutting tool has a rod shape extending from a front end to a rear end, and includes a holder having a front end surface located on the front end side, an upper surface extending from the front end surface toward the rear end, a lower surface located opposite the upper surface, a first side surface located between the upper surface and the lower surface and extending from the front end surface toward the rear end, a second side surface located opposite the first side surface, and a pocket opening to the front end surface, the upper surface, and the first side surface; a cutting insert located in the pocket and having a cutting edge; a sensor located on an outer surface of the holder on the front end side and detecting a physical quantity of the holder; and a wiring member electrically connected to the sensor and extending from the sensor side toward the rear end, wherein the holder further has a groove opening to both the lower surface and the second side surface and extending from the front end side toward the rear end, and the wiring member is located in the groove.

[0066] (2) In the cutting tool of (1), the wiring member may have a wiring conductor electrically connected to the sensor and extending from the sensor side toward the rear end, and a cylindrical holding member located in the groove, extending from the tip side toward the rear end, and holding the wiring conductor.

[0067] (3) In the cutting tool of (2), the holding member may have a first end face located on the side of the lower surface and a second end face located on the side of the second side surface, and the distance from the upper surface to the first end face may be equal to or less than the distance from the upper surface to the lower surface, and the distance from the first side surface to the second end face may be equal to or less than the distance from the first side surface to the second side surface.

[0068] (4) In the cutting tool of (3), the groove may have a first seating surface connected to the second side surface and a second seating surface connected to the bottom surface, and the holding member may further have a first abutment surface located on the opposite side of the first end surface and abutting against the first seating surface, and a second abutment surface located on the opposite side of the second end surface and abutting against the second seating surface.

[0069] (5) In the cutting tool of (4), the first abutment surface and the first seating surface may each be inclined with respect to an imaginary plane parallel to the lower surface so as to move away from the lower surface as they move away from the second side surface.

[0070] (6) In the cutting tool of (4), the second abutment surface and the second seating surface may each be inclined with respect to an imaginary plane perpendicular to the lower surface so as to move away from the second side surface as they move away from the lower surface.

[0071] (7) In any of the cutting tools (4) to (6), the first seating surface and the second seating surface may each be a flat surface, and the groove may further have a connecting surface having a concave curved shape located between the first seating surface and the second seating surface.

[0072] (8) In the cutting tool of (7), the wiring member may be separated from the connection surface.

[0073] (9) In any of the cutting tools (1) to (8), in a cross section perpendicular to the longitudinal direction of the holder, the width of the groove in a direction parallel to the second side surface may be greater than the width of the groove in a direction parallel to the lower surface.

[0074] (10) In the cutting tool according to any one of (1) to (9), the groove may be located closer to the rear end than the pocket.

[0075] (11) In the cutting tool according to any one of (1) to (10), the groove may be positioned closer to the second side surface than the pocket.

[0076] (12) In the cutting tool according to any one of (1) to (11), the holder may further have a rear end surface located opposite the tip surface, and the groove may open to the rear end surface.

[0077] (13) A method for manufacturing a machined product includes the steps of rotating a workpiece, bringing any one of the cutting tools (1) to (12) into contact with the rotating workpiece to cut the workpiece, and removing the cutting tool from the cut workpiece.

[0078] The invention according to the present disclosure has been described above based on the drawings and embodiments. However, the invention according to the present disclosure is not limited to the above-described embodiments. In other words, the invention according to the present disclosure can be modified in various ways within the scope of the present disclosure, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the invention according to the present disclosure. In other words, it should be noted that a person skilled in the art can easily make various modifications or corrections based on the present disclosure. It should also be noted that these modifications or corrections are included in the scope of the present disclosure.

[0079] REFERENCE SIGNS LIST 10 Cutting tool 12 Tool rest 12a Mounting surface 12b Inner wall surface 12c Fixing screw 14 Holder 14a Tip 14b Rear end 14m Main body 16 Cutting insert 18 Clamp 20 Clamp screw 22 Tip surface 24 Rear end surface 26 Upper surface 28 Lower surface 30 First side surface 32 Second side surface 34 Pocket 36 First insert surface 38 Second insert surface 40 Insert side surface 42 Cutting edge 44 Through hole 46 Sensor unit 48 Unit base 48a First portion 48b Second portion 50 First recess 52 Second recess 54 Third recess 56 First sensor 58 Second sensor 60 Third sensor 62 Wiring member 64 Groove 66 First seating surface 68 Second seating surface 70 Wiring conductor 72 Holding member 74 First end surface 76 Second end surface 78 First contact surface 80 Second contact surface 82 Connecting surface

Claims

1. It has a rod shape extending from the front end to the rear end, A tip surface located on the tip side; an upper surface extending from the tip surface toward the rear end; a lower surface located opposite the upper surface; and a first side surface located between the upper surface and the lower surface and extending from the tip surface toward the rear end; a second side opposite the first side; a pocket opening to the tip surface, the top surface, and the first side surface; A holder having a cutting insert located in the pocket and having a cutting edge; a sensor located on an outer surface of the holder on the side of the tip, the sensor detecting a physical quantity of the holder; a wiring member electrically connected to the sensor and extending from the sensor side toward the rear end, the holder further has a groove that opens on both the lower surface and the second side surface and extends from the tip end side toward the rear end, The wiring member is located within the groove.

2. The wiring member is a wiring conductor electrically connected to the sensor and extending from the sensor side toward the rear end; The cutting tool according to claim 1 , further comprising: a cylindrical holding member located within the groove, extending from the tip end toward the rear end, and holding the wiring conductor.

3. The holding member is A first end surface located on the lower surface side; a second end surface located on the second side surface side, a distance from the upper surface to the first end surface is equal to or less than a distance from the upper surface to the lower surface; The cutting tool according to claim 2 , wherein a distance from the first side surface to the second end surface is equal to or less than a distance from the first side surface to the second side surface.

4. The groove is A first seating surface connected to the second side surface; A second seating surface connected to the lower surface, The holding member is a first abutment surface located on the opposite side of the first end surface and abutting the first seating surface; The cutting tool according to claim 3 , further comprising: a second abutment surface located opposite the second end surface and abutting the second seating surface.

5. The cutting tool according to claim 4 , wherein the first contact surface and the first seating surface are each inclined with respect to an imaginary plane parallel to the lower surface so as to move away from the lower surface with increasing distance from the second side surface.

6. The cutting tool according to claim 4 , wherein the second contact surface and the second seating surface are each inclined with respect to an imaginary plane perpendicular to the lower surface so as to move away from the second side surface with increasing distance from the lower surface.

7. The first seating surface and the second seating surface are each a flat surface, The cutting tool according to claim 4 , wherein the groove further includes a connecting surface having a concave curved shape and located between the first seating surface and the second seating surface.

8. The cutting tool according to claim 7 , wherein the wiring member is spaced apart from the connection surface.

9. In a cross section perpendicular to the longitudinal direction of the holder, The cutting tool according to claim 1 , wherein a width of the groove in a direction parallel to the second side surface is greater than a width of the groove in a direction parallel to the lower surface.

10. The cutting tool according to claim 1 , wherein the groove is located closer to the rear end than the pocket.

11. The cutting tool according to claim 1 , wherein the groove is located closer to the second side surface than the pocket.

12. The holder further has a rear end surface located opposite the front end surface, The cutting tool according to claim 1 , wherein the groove is open to the rear end surface.

13. Rotating the workpiece; a step of bringing the cutting tool according to any one of claims 1 to 6 into contact with the rotating workpiece to cut the workpiece; and removing the cutting tool from the cut workpiece.