WO2022123740A1

WO2022123740A1 - Cutting tool

Info

Publication number: WO2022123740A1
Application number: PCT/JP2020/046112
Authority: WO
Inventors: 雄介小池; 浩充栗山
Original assignee: 住友電気工業株式会社
Priority date: 2020-12-10
Filing date: 2020-12-10
Publication date: 2022-06-16
Also published as: JP7156581B1; JPWO2022123740A1

Abstract

This cutting tool comprises a shaft part extending from a first end section to a second end section along a rotational axis, and a sensor unit disposed so as to surround one long-axis-direction portion of the shaft part. The cutting tool rotates about the rotational axis of the shaft part, thereby cutting a workpiece. The sensor unit includes a sensor module, and a case that accommodates the sensor module. The sensor module includes: a sensor that detects a physical quantity pertaining to the shaft part; a substrate that is electrically connected to the sensor; and a wireless communication unit that is electrically connected to the substrate and that transmits, to the outside, signals including information about the physical quantity detected by the sensor. The case includes a retaining part that retains the sensor module.

Description

Cutting tools

This disclosure relates to cutting tools.

A technique for grasping the state of a cutting tool by measuring the physical amount of the cutting tool with a sensor during machining with the cutting tool is known (for example, US Patent Application Publication No. 2015/0261207 (Patent Document 1), Japanese Patent Application Laid-Open No. 2018-54611 (Patent Document 2), Japanese Patent Application Laid-Open No. 2009-285804 (Patent Document 3), International Publication No. 2017/002762 (Patent Document 4), Patent No. 5988066 (Patent Document 5), Practical use. New Document Registration No. 3170029 (Patent Document 6), Japanese Patent Application Laid-Open No. 2015-77658 (Patent Document 7), International Publication No. 2015-056495 (Patent Document 8), European Patent Application Publication No. 3292929 (Patent Document 9) and European Patent Application Publication No. 32929930 (Patent Document 10)).

U.S. Patent Application Publication No. 2015/0261207 Japanese Unexamined Patent Publication No. 2018-54611 Japanese Unexamined Patent Publication No. 2009-285804 International Publication No. 2017/002762 Japanese Unexamined Patent Publication No. 2016-221665 Utility model registration No. 3170029 JP-A-2015-77658 International Publication No. 2015-056495 European Patent Application Publication No. 3292929 European Patent Application Publication No. 32929930

A cutting tool according to the present disclosure includes a shaft portion extending from a first end portion to a second end portion along a rotation axis, a sensor portion arranged so as to surround a part of the shaft portion in the longitudinal direction, and a sensor portion. To prepare for. This cutting tool is a cutting tool that cuts a workpiece by rotating around the rotation axis of the shaft portion. The sensor unit includes a sensor module and a case for accommodating the sensor module. The sensor module transmits to the outside a sensor that detects the physical quantity of the shaft portion, a substrate that is electrically connected to the sensor, and a signal that is electrically connected to the substrate and contains information on the physical quantity detected by the sensor. Including the wireless communication unit. The case includes a holder that holds the sensor module.

FIG. 1 is a schematic perspective view showing the structure of a cutting tool. FIG. 2 is a schematic perspective view showing the structure of the shaft portion. FIG. 3 is a schematic perspective view showing the structure of the shaft portion as viewed from a viewpoint different from that of FIG. 2. FIG. 4 is a schematic plan view showing the structure of the shaft portion as viewed from the first end side in the direction of the rotation axis. FIG. 5 is a schematic plan view showing the structure of the shaft portion as viewed from the second end side in the direction of the rotation axis. FIG. 6 is a schematic plan view showing the structure of the shaft portion as viewed in the direction perpendicular to the axial direction. FIG. 7 is a schematic cross-sectional view showing a cross section along the line segment VII-VII of FIG. FIG. 8 is a schematic cross-sectional view showing a state in which the substrate module is housed in the case. FIG. 9 is a schematic perspective view showing the structure of the strain sensor component. FIG. 10 is a schematic plan view showing the structure of the substrate module. FIG. 11 is a schematic cross-sectional view showing a cross section taken along the line segment XI-XI of FIG. FIG. 12 is a schematic plan view showing a state in which the substrate module is housed in the case. FIG. 13 is a schematic perspective view showing the structure of the case body. FIG. 14 is a schematic perspective view showing the structure of the first fixing member. FIG. 15 is a schematic perspective view showing the structure of the second fixing member. FIG. 16 is a schematic perspective view showing the structure of the lid (upper wall portion). FIG. 17 is a schematic perspective view showing the structure of the holding portion. FIG. 18 is a schematic plan view showing the structure of the substrate module when the substrate of the modified example is adopted. FIG. 19 is a schematic cross-sectional view showing a cross section along the line segment XIX-XIX of FIG.

[Problems to be solved by this disclosure]
If the balance of rotation of the cutting tool deteriorates due to the adoption of the sensor unit, the machining accuracy and durability of the cutting tool may decrease. It is one of the objects of the present disclosure to provide a cutting tool capable of suppressing deterioration of the rotation balance due to the adoption of the sensor unit.
[Effect of this disclosure]

According to the cutting tool of the present disclosure, it is possible to suppress deterioration of the rotational balance due to the adoption of the sensor unit.
[Explanation of Embodiments of the present disclosure]

First, the embodiments of the present disclosure will be listed and described. The cutting tool of the present disclosure includes a shaft portion extending from a first end portion to a second end portion along a rotation axis, and a sensor portion arranged so as to surround a part of the shaft portion in the longitudinal direction. .. This cutting tool is a cutting tool that cuts a workpiece by rotating around the rotation axis of the shaft portion. The sensor unit includes a sensor module and a case for accommodating the sensor module. The sensor module transmits to the outside a sensor that detects the physical quantity of the shaft portion, a substrate that is electrically connected to the sensor, and a signal that is electrically connected to the substrate and contains information on the physical quantity detected by the sensor. Including the wireless communication unit. The case includes a holder that holds the sensor module.

In the cutting tool of the present disclosure, the sensor detects the physical quantity of the shaft portion, and the signal including the information of the physical quantity is transmitted to the outside by the wireless communication unit. The sensor module, including the sensor and the wireless communication unit, is held in an appropriate position by the holding unit included in the case. Therefore, according to the cutting tool of the present disclosure, it is possible to suppress deterioration of the rotational balance due to the adoption of the sensor unit including the sensor module and the case.

In the above-mentioned cutting tool, the first end portion may be the end portion on the side where the blade for cutting the workpiece is arranged. The case has a cylindrical side wall that surrounds the outer peripheral surface of the shaft, a bottom wall that closes the opening of the side wall on the first end side of the shaft, and a side wall on the second end side of the shaft. It may include an upper wall portion that closes the opening of the. A case having such a structure is suitable as a case for accommodating a sensor module.

In the above cutting tool, the holding portion may be arranged on the bottom wall portion or the upper wall portion. With such a configuration, it becomes easy to hold the sensor module in an appropriate position by the holding portion.

In the above cutting tool, the bottom wall portion may be made of metal. At least a part of the upper wall portion and the side wall portion may be made of resin. Chips of the workpiece are likely to collide with the bottom wall portion located on the first end side, which is the end on the side where the blade for cutting the workpiece is arranged. Since the bottom wall portion is made of metal, it becomes easy to ensure sufficient durability against collision of chips. On the other hand, since at least a part of the upper wall portion and the side wall portion is made of resin, the signal from the wireless communication unit can be easily transmitted to the outside.

In the cutting tool, the sensor module may further include a secondary battery that supplies power to the sensor and a charging port that is connected to the secondary battery and exposed to the outside on the side wall. With this configuration, power can be supplied to the sensor from a secondary battery arranged inside the case. Further, by arranging the charging port so as to be exposed to the outside on the side wall portion, it is possible to prevent chips from colliding with the charging port.

In the above cutting tool, the holding portion may include at least a pair of wall portions. The holding portion may be held by sandwiching at least a part of the sensor module between the at least a pair of wall portions. This configuration makes it easy to hold the sensor module by the holding portion.

In the above cutting tool, the sensor portion may further include an annular fixing member for fixing the case to the shaft portion. The outer peripheral surface of the shaft portion surrounded by the sensor portion may have a first flat portion. The inner peripheral surface of the fixing member may have a second flat portion facing the first flat portion in the radial direction of the shaft portion. It may be restricted that the sensor portion rotates relative to the shaft portion due to the contact between the first flat portion and the second flat portion. With this configuration, it becomes easy to install the sensor portion on the shaft portion while restricting the rotation of the sensor portion relative to the shaft portion.

In the above cutting tool, the outer peripheral surface of the shaft portion surrounded by the sensor portion when viewed in the direction along the rotation axis may have a polygonal shape including the first flat portion. The inner peripheral surface of the fixing member may have a portion corresponding to the polygonal shape, and the portion corresponding to the polygonal shape may be the second flat portion. With this configuration, it becomes easier to install the sensor portion on the shaft portion while restricting the rotation of the sensor portion relative to the shaft portion.

In the above-mentioned cutting tool, the case has a cylindrical side wall portion that surrounds the outer peripheral surface of the shaft portion, a bottom wall portion that closes the opening of the side wall portion on the first end side of the shaft portion, and a second end of the shaft portion. It may include an upper wall portion that closes the opening of the side wall portion on the portion side. The fixing member may be fixed to the bottom wall portion or the upper wall portion. With this configuration, it becomes easier to install the sensor portion on the shaft portion while restricting the rotation of the sensor portion relative to the shaft portion.

In the above cutting tool, the fixing member may be formed with a screw hole penetrating in the direction along the rotation axis. The fixing member may be fixed to the bottom wall portion or the upper wall portion by screws. The screw may penetrate the screw hole and enter the bottom wall portion or the upper wall portion. With this configuration, it becomes easier to install the sensor portion on the shaft portion.

In the above cutting tool, a groove extending in the circumferential direction of the shaft portion may be formed on the outer peripheral surface of the shaft portion. A part of the fixing member may be fitted in this groove. This configuration facilitates positioning of the sensor unit with respect to the shaft unit in the direction of the rotation axis.

In the above cutting tool, the sensor module may be arranged so that the straight line passing through the rotation axis when viewed in the direction along the rotation axis is a perpendicular line to the portion of the surface of the substrate on which the wireless communication unit is mounted. .. With this configuration, it is possible to suppress the centrifugal force due to the rotation of the cutting tool, which is applied to the wireless communication unit having a relatively large mass, from being applied in the direction along the surface of the substrate. As a result, it is possible to prevent an abnormality from occurring in the electrical connection or the like of the wireless communication unit.

In the cutting tool, the sensor module may further include at least one component selected from the group consisting of AD converters, switches, connectors, variable resistors and battery holders mounted on the substrate. The sensor module may be arranged so that the straight line passing through the axis of rotation when viewed in the direction along the axis of rotation is a perpendicular line to the portion of the surface of the substrate on which the at least one component is mounted. With this configuration, it is possible to suppress the centrifugal force due to the rotation of the cutting tool applied to these parts having a relatively large mass in the direction along the surface of the substrate. As a result, it is possible to prevent an abnormality from occurring in the electrical connection or the like of these parts.
[Details of Embodiments of the present invention]

Next, an embodiment of the cutting tool according to the present disclosure will be described below with reference to the drawings. In the following drawings, the same or corresponding parts will be given the same reference number and the explanation will not be repeated.
(Overview of cutting tool structure)

FIG. 1 is a schematic perspective view showing the structure of a cutting tool. First, the outline of the structure of the cutting tool will be described with reference to FIG. The cutting tool 1 in the present embodiment includes a shaft portion 10 and a sensor portion 20. The shaft portion 10 extends from the first end portion 10A to the second end portion 10B along the rotation axis A. The sensor portion 20 is arranged so as to surround a part of the shaft portion 10 in the longitudinal direction. The shaft portion 10 is formed with a plurality of (here, four) recesses 13 that open at the first end portion 10A and the outer peripheral surface at equal intervals in the circumferential direction. A cutting tip 91 is attached to the wall surface defining the recess 13. The work piece can be machined by rotating the cutting tool 1 around the rotation axis A and bringing the cutting tip 91 into contact with the work piece (not shown). That is, the cutting tool 1 is a cutting tool that cuts a workpiece by rotating around the rotation axis A of the shaft portion 10.
(Structure of shaft part)

Next, the details of each part of the cutting tool will be explained. FIG. 2 is a schematic perspective view showing the structure of the shaft portion as seen from the second end portion 10B side. FIG. 3 is a schematic perspective view showing the structure of the shaft portion as seen from the side of the first end portion 10A. FIG. 4 is a schematic plan view showing the structure of the shaft portion as viewed from the first end side in the direction of the rotation axis. FIG. 5 is a schematic plan view showing the structure of the shaft portion as viewed from the second end side in the direction of the rotation axis. FIG. 6 is a schematic plan view showing the structure of the shaft portion as viewed in the direction perpendicular to the axial direction. FIG. 7 is a schematic cross-sectional view showing a cross section along the line segment VII-VII of FIG. The structure of the shaft portion 10 will be described with reference to FIGS. 2 to 7.

With reference to FIGS. 2 and 3, the shaft portion 10 includes a main body portion 11 and a diameter-expanded portion 12 as a first region. The main body 11 has a cylindrical shape. The rotation axis A coincides with the central axis of the main body 11. The enlarged diameter portion 12 is a portion having a larger diameter than the main body portion 11. The position of the enlarged diameter portion 12 in the longitudinal direction of the main body portion 11 is not particularly limited, but in the present embodiment, it is arranged in the central portion in the longitudinal direction of the main body portion 11. The enlarged diameter portion 12 is arranged in a region of the shaft portion 10 surrounded by the sensor portion 20.

With reference to FIGS. 2 to 4, as described above, the cutting tip 91 is attached to the wall surface defining the recess 13 of the shaft portion 10. The cutting tip 91 is fixed to the shaft portion 10 by inserting a screw 92 into a screw hole formed in the cutting tip 91 and tightening the screw 92.

With reference to FIGS. 2 to 6, the enlarged diameter portion 12 has an octagonal columnar shape. With reference to FIGS. 4 and 5, the enlarged diameter portion 12 has an octagonal shape when viewed in a direction along the rotation axis A. More specifically, the enlarged diameter portion 12 has an octagonal shape in which four right-angled isosceles triangles having the same shape are removed from each of the four square portions in the cross section perpendicular to the rotation axis A. ing. The axis of rotation A passes through the center of gravity of this octagon. The shape of this octagon is the same in the direction along the rotation axis A. The central axis of the main body portion 11 and the central axis of the enlarged diameter portion 12 coincide with each other. Here, the central axis of the enlarged diameter portion 12 means a straight line passing through the center of gravity of the octagon.

With reference to FIGS. 4 and 5, when viewed in the direction along the axis of rotation A, the octagon has an outer peripheral surface 12A corresponding to the alternately arranged long sides and an outer circumference corresponding to a short side shorter than the long side. It is composed of a surface 12B. The angles θ formed by the perpendicular lines LA and LB passing through the rotation axis A on the outer peripheral surfaces _12A and _12B of the enlarged diameter portions 12 corresponding to the sides of the octagons adjacent to each other in the circumferential direction are equal to each other. Specifically, the angle θ is 45 °. The octagonal shape is not limited to the above shape, and the outer peripheral surface 12A and the outer peripheral surface 12B may have the same length when viewed in the direction along the rotation axis A.

With reference to FIGS. 2 to 6, each outer peripheral surface 12B is formed with a first recess 16 extending in a direction along the rotation axis A. The bottom surface 16A defining the first recess 16 is a flat surface. The first recess 16 is arranged at a position intersecting the perpendicular line _LB. The first recess 16 penetrates the outer peripheral surface 12B in the direction along the rotation axis A. Second recesses 15 extending in the circumferential direction of the enlarged diameter portion 12 are formed on the outer

peripheral surfaces

12A and 12B of the enlarged diameter portion 12. The second recess 15 is formed so as to overlap the first recess 16. The second recess 15 intersects (orthogonally) the first recess 16. The second recess 15 is formed over the entire circumference of the outer

peripheral surfaces

12A and 12B of the enlarged diameter portion 12. That is, the second recess 15 is formed in an annular shape.

With reference to FIGS. 6 and 7, the depth d ₂ of the second recess 15 is larger than the depth d ₁ of the first recess 16. A first small diameter portion 11A having a smaller diameter than the other portions is formed at the boundary portion of the main body portion 11 with the enlarged diameter portion 12 on the first end portion 10A side. A second small diameter portion 11B having a smaller diameter than the other portions is formed at the boundary portion of the main body portion 11 with the enlarged diameter portion 12 on the second end portion 10B side. The shaft portion 10 is formed with a through hole 10C that penetrates the shaft portion 10 in the direction along the rotation axis A. The through hole 10C extends so as to include the rotation axis A.
(Structure of sensor part)

Next, the structure of the sensor unit 20 will be described with reference to FIGS. 8 to 17. With reference to FIG. 8, the sensor unit 20 includes a sensor module 80, a case 21 for accommodating the sensor module 80, and a resin filler 93 filled inside the case 21. The case 21 has a cylindrical side wall portion 23 that surrounds the outer peripheral surface of the shaft portion 10, a bottom wall portion 24 that closes the opening of the side wall portion 23 on the first end portion 10A side of the shaft portion 10, and a first shaft portion 10. 2 includes an upper wall portion 22 that closes the opening of the side wall portion 23 on the end portion 10B side. The sensor module 80 includes a plurality of strain sensors 31 as a plurality of first sensors, a substrate 49 electrically connected to the strain sensor 31, and a wireless communication unit 51 electrically connected to the substrate 49 (FIG. 10, FIG. FIG. 11), a secondary battery 98 that supplies power to the strain sensor 31, and a charging port 99 that is connected to the secondary battery 98 and is exposed to the outside on the outer peripheral surface of the case 21. The secondary battery 98 and the substrate 49 (circuit pattern on the substrate 49) are electrically connected by the wiring 98B. The secondary battery 98 and the charging port 99 are electrically connected by wiring 98A. The strain sensor 31 detects the strain of the shaft portion 10 as a first physical quantity. The wireless communication unit 51 transmits a signal including strain information detected by the strain sensor 31 to the outside.

With reference to FIG. 9, the strain sensor 31 constitutes the strain sensor component 30. The strain sensor component 30 includes a strain sensor 31 and a wiring 32 connected to the strain sensor 31 and having a connector 33 at its tip. The wiring 32 has a strip-shaped shape. The strain sensor 31 is arranged near one end of the wiring 32. A connector 33 is arranged at the other end of the wiring 32.

With reference to FIGS. 10 and 11, the substrate 49 constitutes the substrate module 40. The substrate 49 includes a substrate main body made of an insulator such as resin, and a circuit pattern (not shown) made of a conductor such as copper formed on the surface of the substrate main body. The board module 40 includes a board 49, a wireless communication unit 51, an acceleration sensor 52 as a second sensor, a socket 53, and an AD converter 54. The wireless communication unit 51, the acceleration sensor 52, the socket 53, and the AD converter 54 are arranged on one main surface of the substrate 49 and are electrically connected to the substrate 49 (circuit pattern of the substrate 49). The acceleration sensor 52 detects the acceleration of the shaft portion 10 as a second physical quantity. A plurality of acceleration sensors 52 are arranged on the substrate 49. The wireless communication unit 51 is electrically connected to the acceleration sensor 52 via the substrate 49. The wireless communication unit 51 transmits a signal including information on the acceleration of the shaft unit 10 detected by the acceleration sensor 52 to the outside.

The board 49 is a rigid board. The substrate 49 has a strip-shaped shape. The substrate 49 includes a first zone 41, a second zone 42, a third zone 43, a fourth zone 44, a fifth zone 45, a sixth zone 46, a seventh zone 47 and an eighth zone 48. The first area 41 to the eighth area 48 are arranged in this order in the longitudinal direction of the substrate 49. The wireless communication unit 51 and the acceleration sensor 52 are mounted on the first area 41. A socket 53 is mounted in the second area 42. An acceleration sensor 52 is mounted in the third area 43. A socket 53 is mounted in the fourth area 44. An acceleration sensor 52 and an AD converter 54 are mounted in the fifth area 45. A socket 53 is mounted in the sixth area 46. An acceleration sensor 52 is mounted in the seventh area 47. A socket 53 is mounted in the eighth area 48.

A bendable region 49A having a thickness smaller than that of other portions is formed between the adjacent first region 41 to eighth region 48. The bendable region 49A is a groove connecting both ends of the substrate 49 in the width direction (direction perpendicular to the longitudinal direction). The first area 41 is a second area in which the wireless communication unit 51 is mounted. The fifth area 45 is a third area in which the AD converter 54 is mounted. The bendable region 49A is a fourth region having a smaller thickness than the second region and the third region. The lengths of the first area 41, the third area 43, the fifth area 45, and the seventh area 47 in the longitudinal direction of the substrate 49 are the long sides of the octagon when the enlarged diameter portion 12 is viewed in the direction along the rotation axis A. The length of the outer peripheral surface 12A is extended by a constant ratio α. The lengths of the second area 42, the fourth area 44, the sixth area 46, and the eighth area 48 in the longitudinal direction of the substrate 49 are the short sides of the octagon when the enlarged diameter portion 12 is viewed in the direction along the rotation axis A. The length of the outer peripheral surface 12B is extended by the above-mentioned constant ratio α.

Next, case 21 will be described. With reference to FIGS. 8 and 13-17, the case 21 includes a case body 61, a first fixing member 63, a second fixing member 65, a lid 22, and a holding portion 81. As shown in FIG. 13, the case body 61 includes a disk-shaped bottom wall portion 24 having a through hole 61A in the center, and a side wall portion 23 rising from the outer periphery of the bottom wall portion 24 and having a cylindrical shape. The bottom wall portion 24 is formed with a plurality of (here, eight) screw holes 62 penetrating the bottom wall portion 24 in the thickness direction at equal intervals in the circumferential direction. The material constituting the case body 61 is, for example, metal. Examples of the metal that can be adopted include aluminum alloys and iron alloys (steel such as stainless steel). The first fixing member 63 and the second fixing member 65 form an annular fixing member 67 that fixes the case 21 to the shaft portion 10.

With reference to FIG. 14, the first fixing member 63 has an annular flat plate shape divided into two. The first fixing member 63 has a plurality of screw holes 64 in the circumferential direction (here, the first fixing member 63 is divided into two) so as to correspond to the screw holes 62 of the bottom wall portion 24 of the case body 61. 8 pieces in total) are formed at equal intervals. The inner peripheral surface 63A of the first fixing member 63 has a shape corresponding to the first small diameter portion 11A of the shaft portion 10. In a state where the two first fixing members 63 are combined to form an annular shape, the diameter of the inner peripheral surface 63A is the same as or slightly larger than the diameter of the first small diameter portion 11A. The material constituting the first fixing member 63 is, for example, metal. Examples of the metal that can be adopted include aluminum alloys and iron alloys (steel such as stainless steel).

With reference to FIG. 15, the second fixing member 65 is a component having a flat plate arc shape. In this embodiment, the case 21 includes two second fixing members 65. The inner peripheral surface 65A of each second fixing member 65 has a shape corresponding to a part of the planar shape of the outer peripheral surface of the enlarged diameter portion 12, that is, a shape corresponding to a part of an octagon. The second fixing member 65 has a plurality of screw holes 66 (here, each second fixing) so as to correspond to the screw holes 62 of the bottom wall portion 24 of the case body 61 and the screw holes 64 of the first fixing member 63. (Two for each member 65) are formed. The material constituting the second fixing member 65 is, for example, resin.

With reference to FIG. 16, the lid (upper wall portion) 22 has a disk-shaped shape having a through hole 22A in the center. The material constituting the lid 22 is, for example, resin.

With reference to FIGS. 17 and 8, the holding portion 81 is formed from a bottom wall portion 82 having a flat plate annular shape, an annular outer peripheral wall 84 rising from the outer periphery of the bottom wall portion 82, and an inner circumference of the bottom wall portion 82. It includes a rising annular inner peripheral wall 83 and a battery holding portion 85 connected to the inner peripheral side of the inner peripheral wall 83. The inner peripheral wall 83 extends along the outer peripheral wall 84. The distance between the inner peripheral wall 83 and the outer peripheral wall 84 is substantially constant over the entire circumference. When viewed in the axial direction, the gap between the inner peripheral wall 83 and the outer peripheral wall 84 has an octagonal shape in which the enlarged diameter portion 12 is viewed in the direction along the rotation axis A and is enlarged at a constant rate. is doing. When viewed in the axial direction, the gap between the inner peripheral wall 83 and the outer peripheral wall 84 corresponds to the lengths of the first zone 41, the third zone 43, the fifth zone 45, and the seventh zone 47 in the longitudinal direction of the substrate 49. It has an octagonal shape in which the long sides of the length corresponding to the second area 42, the fourth area 44, the sixth area 46, and the eighth area 48 are alternately arranged. There is. The distance between the inner peripheral wall 83 and the outer peripheral wall 84 is the same as the thickness of the substrate module 40 or slightly larger than the thickness of the substrate module 40. The holding portion 81 has a shape that allows the outer peripheral wall 84 to be arranged inside the case main body 61 so as to be along the inner circumference of the side wall portion 23 of the case main body 61.

Next, the installation of the strain sensor component 30, the board module 40, and the case 21 on the shaft portion 10 will be described. The strain sensor component 30 is arranged so that the strain sensor 31 straddles the second recess 15 and the strain sensor 31 is housed in the first recess 16 (see FIGS. 2, 4, 8, etc.). The strain sensor component 30 is installed on each of the four outer peripheral surfaces 12B. As a result, when viewed in the direction along the rotation axis A, the strain sensor 31 forms 90 ° with each other in the vertical lines LB passing through the rotation axis _A on the outer peripheral surface of the enlarged diameter portion 12 corresponding to each side of the octagon. It is arranged on all of the outer peripheral surfaces 12B (outer peripheral surfaces corresponding to the short sides) of the enlarged diameter portion 12.

The case 21 can be installed in a state where the strain sensor component 30 is installed on the shaft portion 10. Specifically, first, the holding portion 81 is arranged inside the case main body 61 so that the outer peripheral wall 84 is along the inner circumference of the side wall portion 23 of the case main body 61. In this state, the case body 61 is arranged so that the body portion 11 of the shaft portion 10 penetrates the through hole 61A of the bottom wall portion 24 of the case body 61. The first fixing member 63 is fitted into the first small diameter portion 11A so that the inner peripheral surface 63A comes into contact with the bottom wall of the first small diameter portion 11A of the main body portion 11 in a state of being arranged on the bottom wall portion 24. .. That is, the first fixing member 63 constituting the fixing member 67 is fitted into the first small diameter portion 11A which is a groove formed so as to extend in the circumferential direction on the outer peripheral surface of the shaft portion 10. As a result, the sensor unit 20 is positioned with respect to the shaft unit 10 in the direction along the rotation axis A.

The second fixing member 65 is arranged so that the inner peripheral surface 65A comes into contact with the outer

peripheral surfaces

12A and 12B of the enlarged diameter portion 12 in a state of being arranged on the first fixing member 63. Then, the case body 61 and the first fixing member 63 are formed by the screw 69 that penetrates the screw hole 66 of the second fixing member 65 and the screw hole 64 of the first fixing member 63 and reaches the screw hole 62 of the bottom wall portion 24. And the second fixing member 65 are fixed to each other. At this time, since the inner diameter of the first fixing member 63 corresponds to the outer diameter of the first small diameter portion 11A, the central axis of the case body 61 and the rotation axis A coincide with each other. Further, since the inner peripheral surface 65A of the second fixing member 65 has a shape corresponding to a part of the planar shape of the outer peripheral surface of the enlarged diameter portion 12 (a shape corresponding to a part of the octagon), the case main body. The rotation of the 61 in the circumferential direction relative to the shaft portion 10 is hindered. That is, the inner peripheral surface 65A of the second fixing member 65 constituting the fixing member 67 corresponds to the second flat portion (corresponding to the octagonal side) facing the outer

peripheral surfaces

12A and 12B of the enlarged diameter portion 12 as the first flat portion. The area to be used) is included. Then, the sensor portion 20 rotates relative to the shaft portion 10 due to the contact between the outer

peripheral surfaces

12A and 12B which are the first flat portions and the flat regions of the inner peripheral surfaces 65A which are the second flat portions. It is regulated.

With reference to FIGS. 8 and 12, in the board module 40, the main surface on the board 49 on which the wireless communication unit 51, the acceleration sensor 52, the socket 53, the AD converter 54, etc. are mounted is the outer peripheral surface of the enlarged diameter portion 12. It is held by the holding portion 81 by being inserted between the inner peripheral wall 83 and the outer peripheral wall 84 of the holding portion 81 so as to face the 12A and 12B. That is, the holding portion 81 is held by sandwiching the sensor module 80 between the inner peripheral wall 83 and the outer peripheral wall 84, which are a pair of wall portions. At this time, the first area 41, the third area 43, the fifth area 45 and the seventh area 47 are arranged so as to face the outer peripheral surface 12A, and the second area 42, the fourth area 44, the sixth area 46 and the eighth area are arranged. The area 48 is arranged so as to face the outer peripheral surface 12B. Further, the substrate 49 bends in the bendable region 49A, which is a groove connecting both ends in the direction along the rotation axis A (a groove connecting both ends in the width direction).

As a result, when viewed in the direction along the rotation axis A, the substrate 49 is arranged so as to surround the outer

peripheral surfaces

12A and 12B at intervals from the outer

peripheral surfaces

12A and 12B of the enlarged diameter portion 12. The socket 53 is arranged on the main surface of the substrate 49 facing the outer peripheral surface 12B. Then, the connector 33 located at the end of the wiring 32 connected to the strain sensor 31 is connected to the socket 53. As a result, the substrate 49 and the strain sensor 31 are electrically connected. As shown in FIG. 8, the wiring 32 is in a state of being warped in an arch shape. That is, the wiring 32 connects the strain sensor 31 and the socket 53 with slack. The secondary battery 98 is held by the battery holding portion 85 of the holding portion 81.

With reference to FIG. 12, when viewed in the direction along the rotation axis A, the straight line passing through the rotation axis _A is a perpendicular line LA with respect to the portion of the surface of the substrate 49 on which the wireless communication unit 51 and the AD converter 54 are mounted. As such, the sensor module 80 is arranged. Further, the sensor module 80 is arranged so that the straight line passing through the rotation axis _A is a perpendicular line LB with respect to the portion of the surface of the substrate 49 on which the socket 53 (connector) is mounted. As a result, the centrifugal force due to the rotation of the cutting tool 1 applied to these parts having a relatively large mass is suppressed from being applied in the direction along the surface of the substrate 49. As a result, it is possible to prevent an abnormality from occurring in the electrical connection or the like of these parts.

The accelerometer 52 is arranged on the first area 41, the third area 43, the fifth area 45, and the seventh area 47 of the substrate 49. Therefore, when the substrate module 40 is held by the holding portion 81 as described above, the acceleration sensor 52 is viewed in the direction along the rotation axis A, and the acceleration sensor 52 is the outer peripheral surface of the enlarged diameter portion 12 corresponding to each side of the octagon. Of these, the vertical lines LA passing through the rotation axis _A are arranged at positions facing the outer peripheral surface 12A (outer peripheral surface corresponding to the long side) of the enlarged diameter portion 12 forming 90 ° with each other.

With reference to FIGS. 10 and 8, the acceleration sensor 52 and the strain sensor 31 are arranged at the same position in the direction along the rotation axis A. By doing so, it is possible to reduce the axial length required for installing the sensor. As a result, the sensor unit 20 can be made smaller. Here, the state in which the acceleration sensor 52 and the strain sensor 31 are arranged at the same position in the direction along the rotation axis A is the state in the direction along the rotation axis A with reference to FIGS. 8 and 10. The measurement range a of the acceleration sensor 52 (specifically, the range in which the electric resistance wiring for detecting acceleration is arranged) and the measurement range b of the strain sensor 31 (specifically, the electric resistance wiring for detecting strain). It means that it overlaps with (the range in which) is arranged at least in part. The positional relationship between the acceleration sensor 52 and the strain sensor 31 in the direction along the rotation axis A may be changed in consideration of the ease of detecting acceleration and strain. For example, in the direction along the rotation axis A, the strain sensor 31 may be arranged at a position farther from the first end 10A than the acceleration sensor 52 (the side far from the cutting tip 91; the upper side in FIG. 8). The strain of the shaft portion 10 caused by the cutting process increases as the distance from the cutting tip increases. The acceleration of the shaft portion 10 generated by the cutting process increases at a position closer to the cutting tip. Therefore, by adopting such an arrangement, the sensitivity of detecting strain and acceleration by the strain sensor 31 and the acceleration sensor 52 is improved. On the other hand, in the direction along the rotation axis A, the strain sensor 31 may be arranged at a position closer to the first end 10A than the acceleration sensor 52 (the side closer to the cutting tip 91; the lower side in FIG. 8). If the shaft portion 10 is long, the strain of the shaft portion 10 at the position where the strain sensor 31 is arranged may become too large in the above arrangement. In such a case, by arranging the strain sensor 31 at a position closer to the first end 10A than the acceleration sensor 52, the strain sensor 31 detects the magnitude of the strain at the position where the strain sensor 31 is arranged. It can be in a range that is easy to do.

Further, referring to FIGS. 8 and 12, in the present embodiment, the strain sensor 31 includes a temperature sensor. That is, in the present embodiment, as the strain sensor 31, a sensor in which the strain sensor 31 and the temperature sensor are integrated is adopted. The temperature sensor does not necessarily have to be integrated with the strain sensor 31, and may be a separate body. In this case, referring to FIG. 8, the temperature sensor is arranged at the same position as the strain sensor 31 in the direction along the rotation axis A. More specifically, with reference to FIGS. 8 and 12, the temperature sensor corresponds to the measurement range b of the strain sensor 31 in the direction along the rotation axis A among the outer

peripheral surfaces

12A and 12B of the enlarged diameter portion 12. It is arranged at an arbitrary position in the annular region (a band-shaped region whose width corresponds to the measurement range b among the outer

peripheral surfaces

12A and 12B of the enlarged diameter portion 12). Although the temperature sensor is not essential in the cutting tool of the present disclosure, by adopting the temperature sensor, the measurement range of the strain sensor 31 in the position where the strain sensor 31 is installed or in the outer

peripheral surfaces

12A and 12B of the diameter-expanded portion 12 The temperature in the region corresponding to b can be detected. Based on the temperature detected by the temperature sensor, the thermal strain is calculated in the region corresponding to the measurement range b of the strain sensor 31 among the outer

peripheral surfaces

12A and 12B of the position where the strain sensor 31 is installed or the enlarged diameter portion 12. be able to. Thermal strain is the product of temperature change and coefficient of linear expansion. By correcting the strain detected by the strain sensor 31 based on the thermal strain, the strain generated by cutting can be grasped more accurately.

With reference to FIG. 8, with the sensor module 80 housed in the case body 61 as described above, the resin filler 93 is filled inside the case body 61. As a result, the sensor module 80 is fixed to the case body 61. At this time, since the sensor module 80 is held by the holding portion 81, it is suppressed that the sensor module 80 moves to an unintended position due to the inflow of the filler 93 in the flowable state (before solidification). Then, the lid (upper wall portion) 22 is placed on the end surface of the side wall portion 23 and the end surface of the diameter-expanded portion 12, and is fixed to the diameter-expanded portion 12 by, for example, a screw. In this way, the case 21 is fixed to the shaft portion 10 in a state where the sensor module 80 is housed inside.
(Operation of cutting tool)

During the operation of the cutting tool 1, the cutting tool 1 rotates around the rotation axis A. Then, when the cutting tip 91 comes into contact with the workpiece, the workpiece is machined. At this time, the strain and acceleration of the shaft portion 10 are detected by the strain sensor 31 and the acceleration sensor 52, respectively. The strain and acceleration information, which is an analog signal, is converted into a digital signal by the AD converter 54 and then transmitted to the outside by the wireless communication unit 51. Here, since the lid (upper wall portion) 22 of the case 21 is made of resin, the wireless communication unit 51 can transmit a signal to the outside through the lid (upper wall portion) 22. By receiving and analyzing this signal externally, the state of the shaft portion 10 in the plane perpendicular to the rotation axis is grasped.
(Effect of this embodiment)

In the cutting tool 1 of the present embodiment, the strain sensor 31 (including the temperature sensor) and the acceleration sensor 52 detect the strain, temperature and acceleration of the shaft portion 10, and the signal including these information is the wireless communication unit 51. Is sent to the outside by. The sensor module 80 including the sensors (strain sensor 31 and acceleration sensor 52) and the wireless communication unit 51 is held in an appropriate position by the holding unit 81 included in the case 21. Therefore, the cutting tool 1 of the present embodiment is a cutting tool 1 in which deterioration of the rotation balance is suppressed due to the adoption of the sensor unit 20 including the sensor module 80 and the case 21.

Further, in the present embodiment, the case 21 has a bottom wall that closes the opening of the cylindrical side wall portion 23 that surrounds the outer peripheral surface of the shaft portion 10 and the side wall portion 23 on the first end portion 10A side of the shaft portion 10. A portion 24 and an upper wall portion 22 that closes the opening of the side wall portion on the second end portion 10B side of the shaft portion 10 are included. The holding portion 81 is arranged on the bottom wall portion 24. As a result, the holding portion 81 makes it easy to hold the sensor module 80 in an appropriate position.

Further, in the present embodiment, the bottom wall portion 24 is made of metal. The upper wall portion 22 is made of resin. Since the bottom wall portion 24 is made of metal, it is easy to ensure sufficient durability against collision of chips. Since the upper wall portion 22 is made of resin, it is easy to transmit the signal from the wireless communication unit 51 to the outside.

Further, in the present embodiment, the sensor module 80 is connected to the secondary battery 98 that supplies power to the sensors (strain sensor 31 and the acceleration sensor 52) and the secondary battery 98, and is exposed to the outside at the side wall portion 23. Includes a charging port 99 and a charging port 99. As a result, power can be supplied to the sensor from the secondary battery 98 arranged inside the case 21. Further, by arranging the charging port 99 so as to be exposed to the outside on the side wall portion 23, it is suppressed that chips collide with the charging port 99.

Further, in the present embodiment, the holding portion 81 includes a pair of wall portions, an inner peripheral wall 83 and an outer peripheral wall 84. The holding portion 81 holds a part of the sensor module 80 by sandwiching it between the inner peripheral wall 83 and the outer peripheral wall 84. As a result, it is easy to hold the sensor module 80 by the holding portion 81.

Further, in the present embodiment, the fixing member 67 is fixed to the bottom wall portion 24. As a result, it is easier to install the sensor unit 20 on the shaft unit 10 while restricting the rotation of the sensor unit 20 relative to the shaft unit 10.

Further, in the present embodiment, the fixing member 67 is formed with screw holes 64 and 66 penetrating in the direction along the rotation axis A. The fixing member 67 is fixed to the bottom wall portion 24 by a screw 69. The screw 69 penetrates the screw holes 64 and 66 and enters the bottom wall portion 24. As a result, it is easier to install the sensor unit 20 on the shaft unit 10.
(Modification example of board)

Instead of the substrate 49 of the above-described embodiment, which is a rigid substrate, the substrate 49 of the following modified example may be adopted. With reference to FIGS. 18 and 19, the substrate 49 of the present modification is arranged at least in the main body 49B which is a flexible substrate and the first area 41 and the fifth area 45 as the second and third regions. It includes a reinforcing plate 72 having a Young's modulus larger than that of the main body 49B. In this modification, the reinforcing plate 72 is arranged in the first area 41, the third area 43, the fifth area 45, and the seventh area 47. As described above, by adopting the main body portion 49B which is a flexible substrate and having a structure in which only the necessary portion is reinforced by the reinforcing plate 72, the same effect as that of the above embodiment can be obtained.
(Other variants)

In the above embodiment, the case where two types of sensors, the strain sensor 31 and the acceleration sensor 52, are adopted as the first sensor and the second sensor, respectively, has been described. However, for example, the acceleration sensor 52 as the second sensor may be omitted. Further, the strain sensor 31 may be omitted and only the acceleration sensor 52 may be adopted. That is, the first sensor may be an acceleration sensor. Further, a sensor that detects physical quantities other than strain and acceleration may be adopted in place of one or both of the strain sensor 31 and the acceleration sensor 52, or may be adopted in addition to these.

In the above embodiment, the end mill has been described as an example of the cutting tool of the present disclosure, but the cutting tool of the present disclosure is not limited to this. The cutting tool of the present disclosure may be, for example, a drill, a milling cutter, a boring, a reamer, a tap, or the like.

In the above embodiment, the case where the enlarged diameter portion 12 arranged in the region surrounded by the sensor portion 20 of the shaft portion 10 is octagonal when viewed in the direction along the rotation axis A has been described. However, the planar shape of the enlarged diameter portion may be a 4n square (n is a natural number of 2 or more), and may be, for example, a dodecagon, a hexadecagon, or an icosagon.

In the above embodiment, the strain sensor 31 has an enlarged diameter portion in which the vertical lines passing through the rotation axis A of the outer

peripheral surfaces

12A and 12B of the enlarged diameter portion 12 corresponding to each side of the octagon form 90 ° with each other. Although the case where the strain sensors are arranged on all (four surfaces) of the outer peripheral surfaces 12B of the twelve has been described, the strain sensors may be arranged on at least two surfaces. More generally, of the outer peripheral surfaces of the first region (expanded portion) corresponding to each side of the 4n square, the rotation axis is related to the first outer peripheral surface and the first outer peripheral surface. A total of two outer peripheral surfaces of the second outer peripheral surface in which the vertical lines passing through the outer peripheral surface form 90 ° with each other, or in addition to this, a third outer peripheral surface in which the vertical line passing through the rotation axis forms 180 ° in relation to the first outer peripheral surface. A total of three outer peripheral surfaces are set as a set of outer peripheral surfaces, and strain sensors are arranged on each of the set of outer peripheral surfaces. By installing strain sensors on the first outer peripheral surface and the second outer peripheral surface where the perpendiculars passing through the rotation axis form 90 ° with each other, information on the magnitude and direction of the load acting in the plane perpendicular to the rotation axis can be obtained. Obtainable. Furthermore, by installing a strain sensor on the third outer peripheral surface, the influence of the load parallel to the rotation axis is removed, and information on the magnitude and direction of the load acting in the plane perpendicular to the rotation axis can be obtained. Can be obtained accurately. A plurality of the outer peripheral surfaces of the above set may exist. For example, when there are two sets of outer peripheral surfaces, the strain sensor is arranged on each of the outer peripheral surfaces of each set including the two outer peripheral surfaces or the three outer peripheral surfaces. That is, the strain sensors are arranged on a maximum of six outer peripheral surfaces. There is no angle limit between the two sets of perimeter surfaces.

In the above embodiment, the case where the first fixing member 63 and the second fixing member 65 are separate bodies has been described. However, the first fixing member 63 and the second fixing member 65 may be integrated. In this case, the first fixing member 63 and the second fixing member 65 may be an integral metal member.

In the above embodiment, the case where the inside of the case 21 is filled with the resin filler 93 has been described. However, the filler 93 is not an essential configuration and may be omitted if, for example, the sensor module 80 is sufficiently firmly held by the holding portion 81.

Further, in the above embodiment, the case where the holding portion 81 and the fixing member 67 are fixed to the bottom wall 24 has been described, but one or both of the holding portion 81 and the fixing member 67 are fixed to the upper wall portion 22. It may be fixed.

Further, in the above embodiment, the case where the side wall portion 23 is made of metal and the upper wall portion 22 is made of resin has been described. However, the upper wall portion 22 may be made of metal, and at least a part of the side wall portion 23 may be made of resin.

Further, the sensor module 80 may further include at least one component of a switch, a variable resistor and a battery holder mounted on the substrate 49. In this case, the sensor module 80 is such that the straight line passing through the rotation axis _A when viewed in the direction along the rotation axis _A is a perpendicular line LA or a perpendicular line LB with respect to the portion of the surface of the substrate 49 on which the above component is mounted. Is preferably placed.

It should be understood that the embodiments disclosed this time are exemplary in all respects and are not restrictive in any respect. The scope of the present invention is defined by the scope of claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims.

1 Cutting tool, 10 Shaft part, 10A 1st end part, 10B 2nd end part, 10C through hole, 11 main body part, 11A 1st small diameter part, 11B 2nd small diameter part, 12 enlarged diameter part, 12A outer peripheral surface , 12B outer peripheral surface, 13 recess, 15 second recess, 16 first recess, 16A bottom surface, 20 sensor part, 21 case, 22 lid, 22A through hole, 23 side wall part, 24 bottom wall part, 30 sensor parts, 31 strain Sensor, 32 wiring, 33 connector, 40 board module, 41 1st area, 42 2nd area, 43 3rd area, 44 4th area, 45 5th area, 46 6th area, 47 7th area, 48 8th area Area, 49 board, 49A bendable area, 49B main body, 51 wireless communication part, 52 acceleration sensor, 53 socket, 54 AD converter, 61 case body, 61A through hole, 62 screw hole, 63 first fixing member, 63A Peripheral surface, 64 screw holes, 65 second fixing member, 65A inner peripheral surface, 66 screw holes, 67 fixing member, 72 reinforcing plate, 80 sensor module, 81 holding part, 82 bottom wall part, 83 inner peripheral wall, 84 outer peripheral wall , 85 Battery holder, 91 Cutting tip, 92 screw, 93 Filling material, 98 Secondary battery, 98A wiring, 98B wiring, 99 ... Charging port, _A rotating shaft, LA, _LA vertical line, θ angle, d ₁ , d ₂ depth, a, b measurement range.

Claims

A shaft that extends from the first end to the second end along the axis of rotation,
A sensor portion arranged so as to surround a part of the shaft portion in the longitudinal direction is provided.
A cutting tool that cuts a workpiece by rotating around the axis of rotation of the shaft portion.
The sensor unit is
A sensor that detects the physical quantity of the shaft portion, a substrate that is electrically connected to the sensor, and a signal that is electrically connected to the substrate and contains information on the physical quantity detected by the sensor are transmitted to the outside. The wireless communication unit, the sensor module including, and
Including a case for accommodating the sensor module.
The case is a cutting tool that includes a holding portion that holds the sensor module.
The first end portion is an end portion on the side where a blade for cutting the workpiece is arranged.
The case is
A cylindrical side wall portion that surrounds the outer peripheral surface of the shaft portion, and
A bottom wall portion that closes the opening of the side wall portion on the first end side of the shaft portion, and a bottom wall portion.
The cutting tool according to claim 1, further comprising an upper wall portion that closes an opening of the side wall portion on the second end side of the shaft portion.
The cutting tool according to claim 2, wherein the holding portion is arranged on the bottom wall portion or the upper wall portion.
The bottom wall is made of metal and
The cutting tool according to claim 2 or 3, wherein at least a part of the upper wall portion and the side wall portion is made of resin.
The sensor module includes a secondary battery that supplies electric power to the sensor, and
The cutting tool according to any one of claims 2 to 4, further comprising a charging port connected to the secondary battery and exposed to the outside at the side wall portion.
The holding portion includes at least a pair of wall portions.
The cutting tool according to any one of claims 1 to 5, wherein the holding portion holds at least a part of the sensor module by sandwiching it between the at least a pair of wall portions.
The sensor portion further includes an annular fixing member that secures the case to the shaft portion.
The outer peripheral surface of the shaft portion surrounded by the sensor portion has a first flat portion.
The inner peripheral surface of the fixing member has a second flat portion facing the first flat portion in the radial direction of the shaft portion.
One of claims 1 to 6, wherein the sensor portion is restricted from rotating relative to the shaft portion when the first flat portion and the second flat portion come into contact with each other. Cutting tool described in.
Looking in the direction along the axis of rotation,
The outer peripheral surface of the shaft portion surrounded by the sensor portion has a polygonal shape including the first flat portion.
The cutting tool according to claim 7, wherein the inner peripheral surface of the fixing member has a portion corresponding to the polygonal shape, and the portion corresponding to the polygonal shape is the second flat portion.
The case is
A cylindrical side wall portion that surrounds the outer peripheral surface of the shaft portion, and
A bottom wall portion that closes the opening of the side wall portion on the first end side of the shaft portion, and a bottom wall portion.
Includes an upper wall portion that closes the opening of the side wall portion on the second end side of the shaft portion.
The cutting tool according to claim 7 or 8, wherein the fixing member is fixed to the bottom wall portion or the upper wall portion.
The fixing member is formed with a screw hole penetrating in a direction along the rotation axis.
The fixing member is fixed to the bottom wall portion or the upper wall portion by a screw, and is fixed to the bottom wall portion or the upper wall portion.
The cutting tool according to claim 9, wherein the screw penetrates the screw hole and enters the bottom wall portion or the upper wall portion.
A groove extending in the circumferential direction of the shaft portion is formed on the outer peripheral surface of the shaft portion.
The cutting tool according to any one of claims 7 to 10, wherein a part of the fixing member is fitted in the groove.
The sensor module is arranged so that a straight line passing through the rotation axis when viewed in a direction along the rotation axis is a perpendicular line to a portion of the surface of the substrate on which the wireless communication unit is mounted. The cutting tool according to any one of claims 1 to 11.
The sensor module further comprises at least one component selected from the group consisting of AD converters, switches, connectors, variable resistors and battery holders mounted on the substrate.
The sensor module is arranged such that a straight line passing through the axis of rotation when viewed in a direction along the axis of rotation is a perpendicular line to a portion of the surface of the substrate on which the at least one component is mounted. The cutting tool according to any one of items 1 to 12.