Turning tool

Abstract

This turning tool comprises: a rod-like body part having a tip part where a cutting tip is held and a base part which is an end part on the opposite side from the tip part in the longitudinal direction; and a strain sensor installed in the body part. The body part includes: a first part that includes the base part; and a second part that is formed at a position separated from the base part in the longitudinal direction so as to be continuous with the first part, and has a cross-sectional area perpendicular to the longitudinal direction larger than that of the first part. The strain sensor is disposed closer to the tip part side than the boundary between the first part and the second part in the longitudinal direction of the body part.

Description

Turning tools

[0001] The present disclosure relates to turning tools.

[0002] A technique is known in which the state of a turning tool is grasped by measuring the strain of the turning tool using a strain sensor during machining with the turning tool (see, for example, International Publication No. WO 2022 / 230148 (Patent Document 1)).

[0003] International Publication No. 2022 / 230148

[0004] A turning tool according to the present disclosure includes a rod-shaped main body having a distal end for holding a cutting tip and a proximal end that is an end opposite the distal end in the longitudinal direction, and a strain sensor installed in the main body. The main body includes a first portion including the proximal end, and a second portion formed in a position longitudinally spaced from the proximal end and connected to the first portion, the second portion having a larger cross-sectional area perpendicular to the longitudinal direction than the first portion. The strain sensor is located on the distal end side of the boundary between the first and second portions in the longitudinal direction of the main body.

[0005] FIG. 1 is a schematic perspective view showing the structure of a turning tool in a first embodiment. FIG. 2 is a schematic cross-sectional view showing the structure of a turning tool in the first embodiment. FIG. 3 is a schematic perspective view showing the structure of a turret. FIG. 4 is a schematic perspective view showing a state in which a turning tool is held by a turret. FIG. 5 is a schematic perspective view showing the structure of a turning tool in a second embodiment. FIG. 6 is a schematic cross-sectional view showing the structure of a turning tool in the second embodiment. FIG. 7 is a schematic perspective view showing the structure of a turning tool in a third embodiment. FIG. 8 is a schematic cross-sectional view showing the structure of a turning tool in the third embodiment. FIG. 9 is a schematic perspective view showing the structure of a turning tool in the fourth embodiment. FIG. 10 is a schematic cross-sectional view showing the structure of a turning tool in the fourth embodiment. FIG. 11 is a schematic perspective view showing the structure of a turning tool in a fifth embodiment. FIG. 12 is a schematic cross-sectional view showing the structure of a turning tool in the fifth embodiment. FIG. 13 is a schematic perspective view showing the structure of a turning tool in the sixth embodiment. FIG. 14 is a schematic cross-sectional view showing the structure of a turning tool in the sixth embodiment. FIG. 15 is a schematic perspective view showing the structure of a turning tool in the seventh embodiment. FIG. 16 is a schematic cross-sectional view showing the structure of a turning tool in the seventh embodiment. Fig. 17 is a schematic cross-sectional view showing the structure of a turning tool in embodiment 7. Fig. 18 is a schematic perspective view showing the structure of a turning tool in embodiment 8. Fig. 19 is a schematic cross-sectional view showing the structure of a turning tool in embodiment 8. Fig. 20 is a schematic perspective view showing the structure of a turning tool in embodiment 9. Fig. 21 is a schematic cross-sectional view showing the structure of a turning tool in embodiment 9.

[0006] [Problem to be Solved by the Present Disclosure] To measure strain in a turning tool, for example, a strain sensor can be installed on the body of the turning tool. The body of the turning tool is held by a holding mechanism of the machine tool. However, according to the inventors' studies, there are cases where the measured strain value is unstable. Specifically, even when the same machining is performed using the same turning tool, the measured strain value may differ beyond the normal error range. If the measured strain value is unstable in this way, there is a problem that, for example, when detecting an abnormality in the turning tool from the measured strain value, it becomes difficult to set a threshold value for determining an abnormality.

[0007] It is an object of the present disclosure to provide a turning tool that is capable of stabilizing the value of the measured strain.

[0008] Effect of the Present Disclosure According to the turning tool of the present disclosure, the measured strain value can be stabilized.

[0009] [Description of Embodiments of the Present Disclosure] First, embodiments of the present disclosure will be described. A turning tool of the present disclosure includes a rod-shaped main body having a tip end for holding a cutting tip and a base end that is the end opposite the tip end in the longitudinal direction, and a strain sensor installed in the main body. The main body includes a first portion including the base end, and a second portion formed continuous with the first portion at a position spaced apart from the base end in the longitudinal direction and having a larger cross-sectional area perpendicular to the longitudinal direction than the first portion. The strain sensor is located on the tip end side of the boundary between the first and second portions in the longitudinal direction of the main body.

[0010] The inventors investigated the reasons why the measured strain values ​​are unstable when a strain sensor is installed on the main body of a turning tool. As a result, they found that the strain values ​​vary when the area where the strain sensor is installed on the main body is constrained by the holding mechanism of the machine tool, but the measured strain values ​​are stable when the area where the strain sensor is installed is not constrained by the holding mechanism of the machine tool. This is thought to be because when the area where the strain sensor is installed on the main body is constrained by the holding mechanism of the machine tool, the manner of constraint by the holding mechanism affects the measured strain values, whereas when the area is not constrained, the manner of constraint by the holding mechanism has a smaller effect on the measured strain values.

[0011] In the turning tool of the present disclosure, the main body includes a second portion having a larger cross-sectional area perpendicular to the longitudinal direction than the first portion. The strain sensor is disposed on the distal end side of the boundary between the first and second portions in the longitudinal direction of the main body. The second portion, which has a larger cross-sectional area perpendicular to the longitudinal direction than the first portion, interferes with the holding mechanism of the machine tool. Therefore, when the turning tool is held by the holding mechanism, the first portion located closer to the base end than the second portion is held, and the region of the main body on the distal end side of the boundary between the first and second portions is not constrained by the holding mechanism. This means that the region of the main body where the strain sensor is disposed is not constrained by the holding mechanism. As a result, the strain value measured by the strain sensor is stabilized. In this way, the turning tool of the present disclosure can stabilize the measured strain value.

[0012] In the turning tool of the present disclosure, the body may further include a third portion formed to include the tip end and having a larger cross-sectional area perpendicular to the longitudinal direction than the first portion. The second portion may be a region including a protrusion formed on the outer peripheral surface of the body, spaced apart from the third portion, between the base end and the third portion in the longitudinal direction of the body. By forming a region including the protrusion on the outer peripheral surface of the body as the second portion, it is possible to easily achieve a state in which the region of the body toward the tip end from the boundary between the first and second portions is not restrained by the holding mechanism.

[0013] In the turning tool of the present disclosure, the body may include a plurality of flat portions. The protrusions may be formed on the same flat surface among the plurality of flat surfaces on a first annular line formed by an intersection of a plane perpendicular to the longitudinal direction of the body and the surface of the body. This configuration more reliably achieves a state in which the region of the body on the tip side of the boundary between the first and second portions is not restrained by the retaining mechanism.

[0014] In the turning tool of the present disclosure, the protrusions may be formed on each of the plurality of flat surfaces, and this configuration makes it possible to more reliably achieve a state in which the region of the body portion on the tip side of the boundary between the first and second portions is not restrained by the holding mechanism.

[0015] In the turning tool of the present disclosure, the body may further include a third portion formed to include the tip portion and having a cross-sectional area perpendicular to the longitudinal direction larger than that of the first portion. The second portion may be connected to the third portion in the longitudinal direction of the body. This configuration also makes it possible to easily achieve a state in which the region of the body on the tip side of the boundary between the first and second portions is not restrained by the holding mechanism.

[0016] In the turning tool of the present disclosure, a first recess may be formed on the outer peripheral surface of the main body. The strain sensor may be housed in the first recess. By housing the strain sensor in the recess in this manner, handling of the turning tool becomes easy.

[0017] In the turning tool of the present disclosure, a second recess may be formed on the outer peripheral surface of the main body. The strain sensor may be arranged to straddle the second recess. By including a second portion having a larger cross-sectional area perpendicular to the longitudinal direction than the first portion, the rigidity of the main body is increased, and the value of strain occurring in the area of ​​the main body where the strain sensor is installed is reduced. In contrast, by forming a second recess in the main body, strain around the second recess can be amplified. Furthermore, by arranging the strain sensor to straddle the second recess, it becomes easier for the strain sensor to detect strain.

[0018] In the turning tool of the present disclosure, a pair of third recesses may be formed on the outer peripheral surface of the main body portion and arranged side by side along a second annular line formed by the intersection of a plane perpendicular to the longitudinal direction of the main body portion and the surface of the main body portion. The strain sensor may be arranged between the pair of third recesses. By forming the third recesses on the main body portion, strain around the third recesses can be amplified. Furthermore, by arranging the strain sensor between the third recesses, it becomes easier to detect strain using the strain sensor.

[0019] [Details of the embodiment of the present invention] Next, an embodiment of a turning tool according to the present disclosure will be described below with reference to the drawings. In the following drawings, the same or corresponding parts are designated by the same reference numerals, and description thereof will not be repeated.

[0020] (Embodiment 1)

[0021] (1) Structure of the Main Body Fig. 1 is a schematic perspective view showing the structure of the turning tool in embodiment 1. Fig. 2 is a schematic cross-sectional view showing the structure of the turning tool in embodiment 1. Fig. 2 shows a cross section along line II-II in Fig. 1 (a cross section in the XZ plane, which is a cross section perpendicular to the Y direction corresponding to the longitudinal direction of the main body 10).

[0022] 1, a turning tool 1 according to the present embodiment includes a rod-shaped main body 10 extending from a tip end 10A to a base end 10B. In this specification, the direction extending from the tip end 10A to the base end 10B, i.e., the longitudinal direction of the main body 10, is the Y direction. The width direction of the main body 10, which is perpendicular to the Y direction, is the X direction. The height direction of the main body 10, which is perpendicular to the X and Y directions, is the Z direction.

[0023] The main body 10 is made of metal. The main body 10 includes a first surface 10C, a second surface 10D, a third surface 10E, a fourth surface 10F, and a fifth surface 10G. The first surface 10C and the fourth surface 10F are planes along the X-Y plane. The first surface 10C and the fourth surface 10F are parallel to each other. The second surface 10D and the third surface 10E are planes along the Y-Z plane. The second surface 10D and the third surface 10E are parallel to each other. The first surface 10C and the fourth surface 10F are perpendicular to the second surface 10D and the third surface 10E. The first surface 10C, the second surface 10D, the third surface 10E, and the fourth surface 10F form the outer peripheral surface of the main body 10. The fifth surface 10G is a plane along the X-Z plane. The fifth surface 10G is perpendicular to the first surface 10C, the second surface 10D, the third surface 10E, and the fourth surface 10F. The fifth surface 10G is the end surface on the base end portion 10B side of the main body 10. The shape of the main body of the present disclosure is not particularly limited, but the main body 10 in the present embodiment has a rectangular parallelepiped shape.

[0024] As shown in FIG. 1 , a recess for holding a cutting tip 90 is formed in the tip portion 10A of the main body 10. The cutting tip 90 and a base plate 81 are disposed in this recess. The cutting tip 90 is stacked on the base plate 81. A fixing portion 82 for fixing the cutting tip 90 is disposed near the tip portion 10A of the main body 10. The cutting tip 90 is held by being sandwiched between the base plate 81 and the fixing portion 82. The cutting tip 90 is detachably fixed by the rotatable fixing portion 82. That is, the cutting tip 90 is held in the tip portion 10A of the main body 10. The turning tool 1 is a cutting tool that cuts a rotating workpiece by bringing the cutting tip 90 into contact with the workpiece. That is, the turning tool 1 is a cutting tool used for turning.

[0025] 1 and 2, the main body 10 includes a first portion 11 including a base end portion 10B, a second portion 12 formed contiguous with the first portion 11 at a position spaced apart from the base end portion 10B in the longitudinal direction (Y direction) and having a larger cross-sectional area perpendicular to the longitudinal direction than the first portion 11, and a third portion 13 formed to include the tip end portion 10A and having a larger cross-sectional area perpendicular to the longitudinal direction (Y direction) than the first portion 11.

[0026] The second portion 12 is a region in the longitudinal direction (Y direction) of the main body 10 between the base end portion 10B and the third portion 13, including a protrusion 12A formed on the outer peripheral surface of the main body 10, more specifically, on the first surface 10C, away from the third portion 13. The shape of the protrusion 12A is not particularly limited, but in this embodiment, it has a rectangular parallelepiped shape. Referring to FIG. 2 , the protrusion 12A is a portion that protrudes from the region surrounded by the outer edge 11A of the first portion 11 when viewed in the longitudinal direction (Y direction) of the main body 10. In other words, the second portion 12 is a region having a portion that protrudes from the region surrounded by the outer edge 11A of the first portion 11 when viewed in the longitudinal direction (Y direction) of the main body 10.

[0027] In this embodiment, there are a plurality of (two) protrusions 12A. Referring to Fig. 1, these two protrusions 12A are formed side by side on a first surface 10C of the plurality of flat surfaces that make up the surface of the main body 10, on a first annular line β formed by the intersection of a plane α perpendicular to the longitudinal direction of the main body 10 and the surface of the main body 10.

[0028] (2) Structure of the Sensor Module Referring to Figures 1 and 2, the turning tool 1 is equipped with a sensor module 40 including a strain sensor 41. The sensor module 40 includes the strain sensor 41 and a wiring portion 42 electrically connected to the strain sensor 41. The strain sensor 41 has a rectangular plate-like shape. The wiring portion 42 has a strip-like shape. The strain sensor 41 is installed on the wiring portion 42.

[0029] (3) Arrangement of strain sensor A first recess 18 is formed in a first surface 10C, which is part of the outer peripheral surface of the main body 10. The first recess 18 is formed to include an area sandwiched between a pair of protrusions 12A. A sensor module 40 including a strain sensor 41 is housed in the first recess 18. That is, the turning tool 1 includes the strain sensor 41 installed in the main body 10.

[0030] 2 , first recess 18 is filled with filler 15. Filler 15 is made of, for example, resin. Sensor module 40 is arranged so as not to be exposed from filler 15. This prevents cutting fluid and the like from coming into contact with sensor module 40 when turning tool 1 is being used for turning. Instead of or in addition to filler 15, a lid member (not shown) that closes the opening of first recess 18 may be provided on main body 10.

[0031] 1 , the strain sensor 41 is disposed closer to the tip end 10A than the boundary γ between the first portion 11 and the second portion 12 in the longitudinal direction (Y direction) of the main body 10. In this embodiment, the entire sensor module 40 including the strain sensor 41 is disposed closer to the tip end 10A than the boundary γ. It is sufficient that the entire strain sensor 41 is disposed closer to the tip end 10A than the boundary γ, and part of the wiring portion 42 may be disposed closer to the base end 10B than the boundary γ.

[0032] (4) Fixing of Turning Tool to Machine Tool The turning tool 1 can be fixed to a machine tool in various ways for use. For example, the turning tool 1 is fixed to a turret, which is a holding mechanism of the machine tool, in the following manner. FIG. 3 is a schematic perspective view showing the structure of the turret. FIG. 4 is a schematic perspective view showing a state in which the turning tool is held by the turret. Referring to FIG. 3, a groove 141 for holding the turning tool 1 is formed in a turret 140, which serves as a holding mechanism included in the machine tool (not shown). The turret 140 includes a bottom wall 142 and a pair of side walls 143 rising from the bottom wall 142. The bottom wall 142 and the side walls 143 define the groove 141. The turning tool 1 is fixed in the groove 141 of the turret 140 using a first fixing member 150, a second fixing member 160, and screws 169A and 169C.

[0033] Specifically, first fixing member 150 has a pair of trapezoidal end faces 155, and a shape including a top face 151, a bottom face 152, a first side face 153, and a second side face 154, each of which has a rectangular shape and is arranged perpendicular to end faces 155 so as to connect pair of end faces 155. Of the parallel sides of trapezoidal end face 155, the side connected to top face 151 is shorter than the side connected to bottom face 152. Second fixing member 160 has a pair of trapezoidal end faces 165, and a shape including a top face 161, a bottom face 162, a first side face 163, and a second side face 164, each of which has a rectangular shape and is arranged perpendicular to pair of end faces 165 so as to connect pair of end faces 165. Of the parallel sides of trapezoidal end face 165, the side connected to top face 161 is longer than the side connected to bottom face 162. The second fixing member 160 is formed with screw holes 165A, 165B, and 165C that penetrate from the top surface 161 to the bottom surface 162.

[0034] 3 and 4 , the first fixing member 150 is arranged so that its bottom surface 152 contacts the bottom wall 142 of the turret 140 and its first side surface 153 contacts the side wall 143 of the turret 140. The turning tool 1 is arranged so that its third surface 10E contacts the bottom wall 142 of the turret 140 and its fourth surface 10F contacts the side wall 143 of the turret 140. The second fixing member 160 is arranged so that its first side surface 163 contacts the second side surface 154 of the first fixing member 150 and its second side surface 164 contacts the first surface 10C of the turning tool 1. The second fixing member 160 is arranged so that its bottom surface 162 faces the bottom wall 142 of the turret 140. Then, screws 169A and 169C are arranged to pass through threaded holes 165A and 165C of the second fixing member 160, respectively, and be inserted into threaded holes (not shown) formed in the bottom wall 142 of the turret 140. Screw 169B is inserted into threaded hole 165B of the second fixing member 160. By tightening screws 169A and 169C, the distance between the bottom surface 162 of the second fixing member 160 and the bottom wall 142 of the turret 140 is reduced. In this way, the second fixing member 160 functions as a shim, and the turning tool 1 is firmly fixed to the turret 140.

[0035] On the other hand, when removing the turning tool 1 from the turret 140, the screw 169B is screwed into the screw hole 165B. The screw 169B passes through the screw hole 165B, and its tip comes into contact with the bottom wall 142. When the screw 169B is further screwed in, the second fixing member 160 moves relative to the turret 140 so that the distance between the bottom surface 162 and the bottom wall 142 increases. This makes it possible to easily remove the second fixing member 160. When the second fixing member 160 is removed, the turning tool 1 is released from the turret 140, and the turning tool 1 can be easily removed from the turret 140. Note that, in the above description, an example has been described in which the turning tool 1 is fixed to the holding mechanism (turret 140) of the machine tool using a wedge-shaped fixing member, but the method of fixing the turning tool 1 to the machine tool is not limited to this. For example, the turning tool 1 may be fixed by screwing a bolt that passes through a part of the holding mechanism of the machine tool so that the tip of the bolt comes into contact with the turning tool 1, or a plate-shaped member may be interposed between the tip of such a bolt and the turning tool 1, and the bolt may be screwed in so that the tip of the bolt comes into contact with the plate-shaped member, thereby pressing the plate-shaped member against the turning tool 1 and fixing it.

[0036] (5) Operation of Turning Tool Referring to FIGS. 1 to 4, when the turning tool 1 is in operation, the turning tool 1 processes the rotating workpiece by contacting the cutting tip 90 with the workpiece. At this time, strain in the main body 10 is detected by the strain sensor 41. The signal containing information on the strain detected by the strain sensor 41 is an analog signal. The analog signal on the strain information is converted to a digital signal by an AD converter (not shown) installed in the main body 10, and then transmitted to a wireless communication unit (not shown) and then to the outside. This signal is received and analyzed externally to determine the state of the turning tool 1.

[0037] (6) Effects of the Present Embodiment In the turning tool 1 of the present embodiment, the main body 10 includes the second portion 12, which has a larger cross-sectional area perpendicular to the longitudinal direction than the first portion 11. The strain sensor 41 is disposed closer to the tip end 10A than the boundary γ between the first portion 11 and the second portion 12 in the longitudinal direction (Y direction) of the main body 10. The second portion 12 (protrusion 12A), which has a larger cross-sectional area perpendicular to the longitudinal direction than the first portion 11, interferes with holding by the turret 140, which is a holding mechanism of the machine tool. Therefore, when the turning tool 1 is held by the turret 140, the first portion 11, which is located closer to the base end 10B than the second portion 12, is held, and the region of the main body 10 closer to the tip end 10A than the boundary γ between the first portion 11 and the second portion 12, is not constrained by the turret 140. As a result, the region of the main body 10 where the strain sensor 41 is disposed is not constrained by the turret 140. As a result, the value of strain measured by the strain sensor 41 becomes stable. In this way, the turning tool 1 of the present embodiment is a turning tool that can stabilize the value of strain measured.

[0038] Second Embodiment Next, a second embodiment, which is another embodiment, will be described. FIG. 5 is a schematic perspective view showing the structure of a turning tool in the second embodiment. FIG. 6 is a schematic cross-sectional view showing the structure of a turning tool in the second embodiment. FIG. 6 shows a cross section taken along line VI-VI in FIG. 5 (a cross section in the XZ plane, which is a cross section perpendicular to the Y direction corresponding to the longitudinal direction of the main body 10). The turning tool 1 in the second embodiment basically has the same structure as the turning tool 1 in the first embodiment and achieves the same effects. However, the turning tool 1 in the second embodiment differs from the turning tool 1 in the first embodiment in the arrangement of the protrusion 12A, the first recess 18, and the sensor module 40.

[0039] Specifically, the protrusion 12A and the first recess 18 of the turning tool 1 of the second embodiment are formed on the third surface 10E of the main body 10. The sensor module 40 is accommodated in the first recess 18, and is thereby disposed on the third surface 10E of the main body 10.

[0040] Even when such a structure is adopted, as in the first embodiment, the second portion 12 (protrusion 12A), which has a larger cross-sectional area perpendicular to the longitudinal direction than the first portion 11, prevents the second portion 12 from being held by the turret 140, which is the holding mechanism of the machine tool, and the area of ​​the main body 10 on the tip portion 10A side of the boundary γ between the first portion 11 and the second portion 12 is not restrained by the turret 140. As a result, the value of strain measured by the strain sensor 41 is stabilized. In this way, the turning tool 1 of this embodiment is a turning tool that can stabilize the value of strain to be measured.

[0041] Third Embodiment Next, a third embodiment, which is yet another embodiment, will be described. FIG. 7 is a schematic perspective view showing the structure of a turning tool in the third embodiment. FIG. 8 is a schematic cross-sectional view showing the structure of a turning tool in the third embodiment. FIG. 8 shows a cross section taken along line VIII-VIII in FIG. 7 (a cross section in the X-Z plane, which is a cross section perpendicular to the Y direction corresponding to the longitudinal direction of the main body 10). The turning tool 1 in the third embodiment basically has the same structure as the turning tool 1 in the first embodiment and achieves the same effects. However, the turning tool 1 in the third embodiment differs from the turning tool 1 in the first embodiment in the arrangement of the protrusion 12A, the first recess 18, and the sensor module 40.

[0042] Specifically, the protrusion 12A and the first recess 18 of the turning tool 1 of the third embodiment are formed on the fourth surface 10F of the main body 10. The sensor module 40 is accommodated in the first recess 18 and is disposed on the fourth surface 10F of the main body 10.

[0043] Even when such a structure is adopted, as in the first embodiment, the second portion 12 (protrusion 12A), which has a larger cross-sectional area perpendicular to the longitudinal direction than the first portion 11, prevents the second portion 12 from being held by the turret 140, which is the holding mechanism of the machine tool, and the area of ​​the main body 10 on the tip portion 10A side of the boundary γ between the first portion 11 and the second portion 12 is not restrained by the turret 140. As a result, the value of strain measured by the strain sensor 41 is stabilized. In this way, the turning tool 1 of this embodiment is a turning tool that can stabilize the value of strain to be measured.

[0044] Fourth Embodiment Next, a fourth embodiment, which is yet another embodiment, will be described. FIG. 9 is a schematic perspective view showing the structure of a turning tool in the fourth embodiment. FIG. 10 is a schematic cross-sectional view showing the structure of a turning tool in the fourth embodiment. FIG. 10 shows a cross section along line X-X in FIG. 9 (a cross section in the X-Z plane, which is a cross section perpendicular to the Y direction corresponding to the longitudinal direction of the main body 10). FIGS. 9 and 10 correspond to FIGS. 1 and 2 of the first embodiment, respectively. The turning tool 1 in the fourth embodiment basically has the same structure as the turning tool 1 in the first embodiment and achieves the same effects. However, the turning tool 1 in the fourth embodiment differs from the turning tool 1 in the first embodiment in the arrangement of the protrusion 12A, the first recess 18, and the sensor module 40.

[0045] Specifically, the protrusions 12A of the turning tool 1 of the fourth embodiment are formed on each of the first surface 10C, the third surface 10E, and the fourth surface 10F of the main body 10. That is, in this embodiment, a plurality of protrusions 12A (two protrusions each) are formed on each of the three flat surfaces (outer peripheral surfaces) of the main body 10, namely, the first surface 10C, the second surface 10D, the third surface 10E, and the fourth surface 10F. First recesses 18 are formed between the two protrusions 12A formed on each of the first surface 10C, the third surface 10E, and the fourth surface 10F. The first recesses 18 are formed on the first surface 10C, the third surface 10E, and the fourth surface 10F. The sensor modules 40 are accommodated in the first recesses 18, and are arranged on the first surface 10C, the third surface 10E, and the fourth surface 10F of the main body 10. That is, in this embodiment, a plurality of (three) sensor modules 40 are arranged in the main body 10 .

[0046] Even when such a structure is adopted, as in the first embodiment, the second portion 12 (protrusion 12A), which has a larger cross-sectional area perpendicular to the longitudinal direction than the first portion 11, prevents the second portion 12 from being held by the turret 140, which is the holding mechanism of the machine tool. Therefore, the area of ​​the main body 10 closer to the tip portion 10A than the boundary γ between the first portion 11 and the second portion 12 is not restrained by the turret 140. As a result, the strain value measured by the strain sensor 41 is stabilized. Thus, the turning tool 1 of this embodiment is a turning tool capable of stabilizing the measured strain value. Furthermore, in this embodiment, multiple (three) sensors 41 are installed on different outer peripheral surfaces of the main body 10. As a result, the strain state in the main body 10 can be grasped in more detail.

[0047] Fifth Embodiment Next, a fifth embodiment, which is yet another embodiment, will be described. FIG. 11 is a schematic perspective view showing the structure of a turning tool in the fifth embodiment. FIG. 12 is a schematic cross-sectional view showing the structure of a turning tool in the fifth embodiment. FIG. 12 shows a cross section taken along line XII-XII in FIG. 11 (a cross section in the X-Z plane, which is a cross section perpendicular to the Y direction corresponding to the longitudinal direction of the main body 10). FIGS. 11 and 12 correspond to FIGS. 1 and 2 of the first embodiment, respectively. The turning tool 1 in the fifth embodiment basically has the same structure as the turning tool 1 in the first embodiment and achieves the same effects. However, the turning tool 1 in the fifth embodiment differs from the turning tool 1 in the structure of the second portion 12.

[0048] Specifically, the second portion 12 of the turning tool 1 of the fifth embodiment includes a pair of extension portions 12C formed on the first surface 10C and extending along the Y direction, and a connecting portion 12D located on the third portion 13 side of the extension portions 12C and connecting the pair of extension portions 12C. The thickness (height in the Z direction) of the pair of extension portions 12C and the connecting portion 12D is constant throughout. The connecting portion 12D is connected to the third portion 13. In other words, in this embodiment, the second portion 12 is connected to the third portion 13 in the longitudinal direction of the main body 10. The first recess 18 is formed in an area sandwiched between the pair of extension portions 12C. The sensor module 40 is accommodated in the first recess 18 and is disposed on the first surface 10C of the main body 10.

[0049] Even when such a structure is adopted, as in the first embodiment, the second portion 12, which has a larger cross-sectional area perpendicular to the longitudinal direction than the first portion 11, prevents the second portion 12 from being held by the turret 140, which is the holding mechanism of the machine tool, and the region of the main body 10 on the tip portion 10A side of the boundary γ between the first portion 11 and the second portion 12 is not restrained by the turret 140. As a result, the value of strain measured by the strain sensor 41 is stabilized. In this way, the turning tool 1 of this embodiment is a turning tool that can stabilize the value of strain to be measured.

[0050] Sixth Embodiment Next, a sixth embodiment, which is yet another embodiment, will be described. FIG. 13 is a schematic perspective view showing the structure of a turning tool in the sixth embodiment. FIG. 14 is a schematic cross-sectional view showing the structure of a turning tool in the sixth embodiment. FIG. 14 shows a cross section taken along line XIV-XIV in FIG. 13 (a cross section in the X-Z plane, which is a cross section perpendicular to the Y direction corresponding to the longitudinal direction of the main body 10). FIGS. 13 and 14 correspond to FIGS. 11 and 12 of the fifth embodiment, respectively. The turning tool 1 in the sixth embodiment basically has the same structure as the turning tool 1 in the fifth embodiment and achieves the same effects. However, the turning tool 1 in the sixth embodiment differs from the turning tool 1 in the shapes of the extension 12C and the connection portion 12D.

[0051] Specifically, the thickness (height in the Z direction) of the connection portion 12D of the turning tool 1 of the sixth embodiment decreases with increasing distance in the Y direction from the third portion 13. The thickness (height in the Z direction) of the pair of extension portions 12C decreases with increasing distance in the Y direction from the third portion 13, and is constant in the regions sandwiching the first recess 18 in the X direction.

[0052] Even when such a structure is adopted, as in the first embodiment, the second portion 12, which has a larger cross-sectional area perpendicular to the longitudinal direction than the first portion 11, prevents the second portion 12 from being held by the turret 140, which is the holding mechanism of the machine tool, and the region of the main body 10 on the tip portion 10A side of the boundary γ between the first portion 11 and the second portion 12 is not restrained by the turret 140. As a result, the value of strain measured by the strain sensor 41 is stabilized. In this way, the turning tool 1 of this embodiment is a turning tool that can stabilize the value of strain to be measured.

[0053] Seventh Embodiment Next, a seventh embodiment, which is yet another embodiment, will be described. FIG. 15 is a schematic perspective view showing the structure of a turning tool in the seventh embodiment. FIGS. 16 and 17 are schematic cross-sectional views showing the structure of a turning tool in the seventh embodiment. FIG. 16 shows a cross section taken along line XVI-XVI in FIG. 15 (a cross section in the Y-Z plane, which is a cross section perpendicular to the Y direction corresponding to the longitudinal direction of the main body 10). FIG. 17 shows a cross section taken along line XVII-XVII in FIG. 15 (a cross section in the Y-Z plane, which is a cross section perpendicular to the X direction, which is the width direction of the main body 10). The turning tool 1 in the seventh embodiment basically has the same structure as the turning tool 1 in the first embodiment and achieves the same effects. However, the turning tool 1 in the seventh embodiment differs from the turning tool 1 in the first embodiment in the structure of the second portion 12 and the installation manner of the strain sensor 41.

[0054] Specifically, the second portion 12 of the turning tool 1 of the seventh embodiment is connected to the third portion 13. The second portion 12 has a larger thickness in the Z direction than the first portion 11, and therefore a larger cross-sectional area perpendicular to the longitudinal direction than the first portion 11. A first recess 18 extending in the Y direction is formed in the second portion 12. Furthermore, in this embodiment, a groove 17 serving as a second recess extending in the X direction is formed in the second portion 12. The groove 17 intersects with the first recess 18 and penetrates the second portion 12 of the main body 10 in the X direction. The groove 17 serving as the second recess is deeper than the first recess 18. The sensor module 40 is housed in the first recess 18. At this time, the strain sensor 41 is arranged to straddle the groove 17. The first recess 18 and the groove 17 are filled with a filler 15.

[0055] Even when such a structure is adopted, as in the first embodiment, the second portion 12, which has a larger cross-sectional area perpendicular to the longitudinal direction than the first portion 11, prevents the second portion 12 from being held by the turret 140, which is the holding mechanism of the machine tool, and the region of the main body 10 on the tip portion 10A side of the boundary γ between the first portion 11 and the second portion 12 is not restrained by the turret 140. As a result, the value of strain measured by the strain sensor 41 is stabilized. In this way, the turning tool 1 of this embodiment is a turning tool that can stabilize the value of strain to be measured.

[0056] Furthermore, in this embodiment, sensor 41 is disposed so as to straddle groove 17. As a result, the rigidity of main body 10 is increased by the presence of second portion 12 having a large cross-sectional area as in this embodiment, and even when strain is small, the formation of groove 17 amplifies the strain around groove 17, making it easy for sensor 41 to detect the strain.

[0057] Eighth Embodiment Next, an eighth embodiment, which is yet another embodiment, will be described. FIG. 18 is a schematic perspective view showing the structure of a turning tool in the eighth embodiment. FIG. 19 is a schematic cross-sectional view showing the structure of a turning tool in the eighth embodiment. FIG. 19 shows a cross section taken along line XIX-XIX in FIG. 18 (a cross section in the Y-Z plane, which is a cross section perpendicular to the Y direction corresponding to the longitudinal direction of the main body 10). The turning tool 1 in the eighth embodiment basically has the same structure as the turning tool 1 in the seventh embodiment and achieves the same effects. However, the turning tool 1 in the eighth embodiment differs from the turning tool 1 in the seventh embodiment in the structure of the second portion 12 and the installation mode of the sensor 41.

[0058] Specifically, in the eighth embodiment, the groove 17 of the seventh embodiment is omitted, and a pair of third recesses 16 is formed in the first surface 10C, which is the outer peripheral surface of the main body 10. The pair of third recesses 16 are arranged side by side along a second annular line δ formed by the intersection of a plane (X-Z plane) perpendicular to the Y direction, which is the longitudinal direction of the main body 10, and the surface of the main body 10. The strain sensor 41 is arranged on the second annular line δ, between the pair of third recesses 16.

[0059] Even when such a structure is adopted, as in the first embodiment, the second portion 12, which has a larger cross-sectional area perpendicular to the longitudinal direction than the first portion 11, prevents the second portion 12 from being held by the turret 140, which is the holding mechanism of the machine tool, and the region of the main body 10 on the tip portion 10A side of the boundary γ between the first portion 11 and the second portion 12 is not restrained by the turret 140. As a result, the value of strain measured by the strain sensor 41 is stabilized. In this way, the turning tool 1 of this embodiment is a turning tool that can stabilize the value of strain to be measured.

[0060] Furthermore, in this embodiment, the sensor 41 is disposed between the third recesses 16. As a result, even if the presence of the second portion 12 with a large cross-sectional area as in this embodiment increases the rigidity of the main body 10 and reduces the strain, the formation of the third recesses 16 amplifies the strain around the third recesses 16, making it easier for the sensor 41 to detect the strain.

[0061] Ninth Embodiment Next, a ninth embodiment, which is yet another embodiment, will be described. FIG. 20 is a schematic perspective view showing the structure of a turning tool in the ninth embodiment. FIG. 21 is a schematic cross-sectional view showing the structure of a turning tool in the ninth embodiment. FIG. 21 shows a cross section taken along line XXI-XXI in FIG. 20 (a cross section in the Y-Z plane, which is a cross section perpendicular to the Y direction corresponding to the longitudinal direction of the main body 10). The turning tool 1 in the ninth embodiment basically has the same structure as the turning tool 1 in the eighth embodiment, and achieves the same effects. However, the turning tool 1 in the ninth embodiment differs from the eighth embodiment in the manner in which the third recess 16 is formed.

[0062] Specifically, in the ninth embodiment, two pairs of third recesses 16 are formed on the first surface 10C, which is the outer peripheral surface of the main body 10. The strain sensor 41 is disposed between the third recesses 16.

[0063] Even when such a structure is adopted, as in the first embodiment, the second portion 12, which has a larger cross-sectional area perpendicular to the longitudinal direction than the first portion 11, prevents the second portion 12 from being held by the turret 140, which is the holding mechanism of the machine tool, and the region of the main body 10 on the tip portion 10A side of the boundary γ between the first portion 11 and the second portion 12 is not restrained by the turret 140. As a result, the value of strain measured by the strain sensor 41 is stabilized. In this way, the turning tool 1 of this embodiment is a turning tool that can stabilize the value of strain to be measured.

[0064] In the present embodiment, the sensor 41 is disposed between the third recesses 16. As a result, as in the eighth embodiment, the formation of the third recesses 16 amplifies the strain around the third recesses 16, making it easier for the sensor 41 to detect the strain.

[0065] It should be understood that the embodiments disclosed herein are illustrative in all respects and are not limiting in any respect. The scope of the present invention is defined not by the above description but by the claims, and it is intended to include all modifications within the meaning and scope of the claims.

[0066] 1 Turning tool, 10 Main body, 10A Tip, 10B Base end, 10C First surface, 10D Second surface, 10E Third surface, 10F Fourth surface, 10G Fifth surface, 11 First part, 11A Outer edge, 12 Second part, 12A Protrusion, 12C Extension portion, 12D Connection portion, 13 Third part, 15 Filler, 16 Third recess, 17 Groove, 18 First recess, 40 Sensor module, 41 Strain sensor, 42 Wiring portion, 81 Sole plate, 82 Fixing portion, 90 Cutting tip, 140 Turret, 141 Groove, 142 Bottom wall, 143 Side wall, 150 First fixing member, 151 Upper surface, 152 Bottom surface, 153 First side surface, 154 Second side surface, 155 End surface, 160 Second fixing member, 161 top surface, 162 bottom surface, 163 first side surface, 164 second side surface, 165 end surface, 165A screw hole, 165B screw hole, 165C screw hole, 169A screw, 169B screw, 169C screw, α surface, β first annular line, γ boundary, δ second annular line.

Claims

1. A turning tool comprising: a rod-shaped main body having a tip end for holding a cutting tip and a base end which is the end opposite the tip end in the longitudinal direction; and a strain sensor installed on the main body, wherein the main body includes a first portion which includes the base end, and a second portion which is formed continuous with the first portion at a position longitudinally away from the base end and has a larger cross-sectional area perpendicular to the longitudinal direction than the first portion; and the strain sensor is positioned longitudinally on the tip side of the boundary between the first portion and the second portion of the main body.

2. A turning tool as described in claim 1, wherein the main body portion is formed to include the tip end and further includes a third portion having a larger cross-sectional area perpendicular to the longitudinal direction than the first portion, and the second portion is an area including a protrusion formed on the outer circumferential surface of the main body portion, spaced apart from the third portion, between the base end portion and the third portion in the longitudinal direction of the main body portion.

3. A turning tool as described in claim 2, wherein the main body portion includes a plurality of flat surfaces, and the protrusions are formed on a first annular line formed by the intersection of a plane perpendicular to the longitudinal direction of the main body portion and the surface of the main body portion, and a plurality of the protrusions are formed on the same flat surface among the plurality of flat surfaces.

4. The turning tool according to claim 3, wherein a plurality of said projections are formed on each of a plurality of said flat surfaces.

5. The turning tool according to claim 1, wherein the main body portion is formed to include the tip portion and further includes a third portion having a cross-sectional area perpendicular to the longitudinal direction larger than that of the first portion, and the second portion is connected to the third portion in the longitudinal direction of the main body portion.

6. A turning tool as claimed in any one of claims 1 to 5, wherein a first recess is formed on the outer peripheral surface of the main body, and the strain sensor is housed within the first recess.

7. A turning tool as claimed in any one of claims 1 to 6, wherein a second recess is formed on the outer peripheral surface of the main body, and the strain sensor is positioned so as to straddle the second recess.

8. A turning tool as claimed in any one of claims 1 to 6, wherein a pair of third recesses are formed on the outer peripheral surface of the main body portion and are arranged side by side along a second annular line formed by the intersection of a plane perpendicular to the longitudinal direction of the main body portion and the surface of the main body portion, and the strain sensor is arranged between the pair of third recesses.

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