Lathe tool

Abstract

To provide a lathe tool which can measure a distance to a processed face at a high precision by making a distance sensor proximate to the processed face.SOLUTION: A lathe tool 1 comprises: a tool body 2 having a head part 21 extending along a tool axis J and having a pedestal 24 at a tip of one side Dj1 of an axial direction Dj along the tool axis J, and an attachment part 22 provided on a base end part of the other side Dj2 of the axial direction with respect to the head part 21; a cutting insert 4, attached on the pedestal 24 so as to be attached and detached; and a radial distance sensor 32 provided on the tool body 2 to detect a distance to a processed face 100m of a workpiece 100 processed by cutting with the cutting insert 4. The radial distance sensor 32 is provided at a position overlapping with the cutting insert 4 in the axial direction Dj and provided by inclination at an inclination angle α where a sensor axis 32c is 0°<α<90°, as viewed from the axial direction Dj, with respect to a line L combining the tool axis J with a cutting edge 42 of the cutting insert 4.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a turning tool. [Background technology]

[0002] In machine tools such as lathes and machining centers, cutting tools are sometimes equipped with electronic components such as sensors to check the condition of the cutting edge of the cutting tool. Patent Document 1 discloses a configuration including a tool body extending along the tool axis and having a pedestal at its tip, a cutting insert removably attached to the pedestal, and a distance sensor provided on the tool body and measuring in the radially outward direction. The distance sensor is provided on the opposite side of the tool axis from the cutting insert. In this configuration, the distance sensor measures the distance to a machined surface (inner diameter surface) machined by the cutting insert and facing radially inward. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-151384 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above configuration, an eddy current sensor, for example, is used as the distance sensor. Because the detection range of an eddy current sensor is narrow, at only a few millimeters, the distance sensor must be brought close to the machining surface within the detection range when performing measurements. However, depending on the structure of the machine tool, the inner diameter of the machining surface, etc., it may not be possible to bring the distance sensor, which is provided on the opposite side of the tool axis from the cutting insert, close to the machining surface.

[0005] In view of the above circumstances, an object of the present invention is to provide a turning tool that can bring a distance sensor close to a machining surface and measure the distance to the machining surface with high accuracy. [Means for solving the problem]

[0006] One embodiment of the turning tool of the present invention comprises a tool body having a head portion extending along a tool axis and having a base seat at one axial tip along the tool axis, and an attachment portion provided at a base end on the other axial side of the head portion; a cutting insert removably attached to the base seat; and a distance sensor provided on the tool body for detecting the distance to the machined surface of a workpiece machined by the cutting insert, wherein the distance sensor is provided at a position overlapping with the cutting insert in the axial direction, and is inclined with respect to a line connecting the tool axis and the cutting edge of the cutting insert at an inclination angle α such that 0°<α<90° when viewed from the axial direction.

[0007] According to one aspect of the turning tool of the present invention, the distance sensor is provided with its axis inclined at an angle α of 0°<α<90° relative to a line connecting the tool axis and the cutting edge of the cutting insert when viewed from the axial direction, so that the cutting insert and the distance sensor are arranged on the same side of the tool axis. This allows the distance sensor to be brought close to the machined surface of the workpiece machined by the cutting insert, regardless of the structure of the machine tool, the inner diameter of the machined surface, etc. Therefore, by bringing the distance sensor close to the machined surface, the distance to the machined surface can be measured with high accuracy.

[0008] In the above turning tool, the distance sensor may be arranged on the outer peripheral surface of the head portion, which is connected circumferentially around the tool axis relative to the base, so that the sensor axis extends in a direction perpendicular to the tangent direction of the outer peripheral surface at the position where the tip of the distance sensor is provided.

[0009] In this case, the distance sensor is provided on the outer peripheral surface of the head unit so that the sensor axis extends in a direction perpendicular to the tangent direction of the outer peripheral surface at the position where the tip of the distance sensor is provided, thereby preventing the sensor axis from tilting relative to the machining surface and preventing a large difference in the distance to the machining surface between one side and the other side in the circumferential direction of the distance sensor, thereby preventing a decrease in the measurement accuracy of the distance to the machining surface.

[0010] In the turning tool, the distance sensor may be provided at a position that avoids interference with a fixing screw that fixes the cutting insert to the head portion.

[0011] In this case, the distance sensor is positioned to avoid interference with the fixing screw that fixes the cutting insert to the head portion, so even if the fixing screw is attached or detached when replacing the cutting insert, the fixing screw can be prevented from hitting the distance sensor and causing positional deviation, etc.

[0012] In the turning tool, the inclination angle α may be set to be 10°<α<30°.

[0013] In this case, the inclination angle α is 10°<α<30°, so the distance sensor can be positioned close to the cutting insert while avoiding interference with the fixing screw that secures the cutting insert to the head. This allows the distance sensor to be more reliably placed close to the machined surface of the workpiece machined by the cutting insert, enabling highly accurate measurement of the distance to the machined surface.

[0014] In the turning tool, the attachment portion may be configured to be fixable to a holder that is attached to a turret of a machine tool.

[0015] In this case, in a turret-type machine tool, the distance sensor can be brought close to the machined surface of the workpiece machined by the cutting insert, making it possible to measure the distance to the machined surface with high precision. [Effects of the Invention]

[0016] According to a turning tool of one aspect of the present invention, the distance sensor can be brought close to the machining surface, and the distance to the machining surface can be measured with high precision. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a perspective view showing a state in which a turning tool according to an embodiment of the present invention is attached to a holder. FIG. [Figure 2] 1 is a perspective view of a turning tool according to an embodiment of the present invention; [Figure 3] 1 is a perspective development view showing a component configuration of a turning tool according to an embodiment of the present invention. FIG. [Figure 4] FIG. 1 is a side view of a turning tool according to an embodiment of the present invention. [Figure 5] 1 is a view of a turning tool according to an embodiment of the present invention, viewed from one side in the axial direction. [Figure 6] FIG. 10 is a diagram showing a state in which a distance sensor of a turning tool according to an embodiment of the present invention measures the distance to the machined surface of a workpiece. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, a turning tool 1 according to an embodiment of the present invention will be described with reference to the drawings. In the following drawings, the scale and number of each structure may differ from the actual structure in order to make each component easier to understand.

[0019] <Turning tools> FIG. 1 is a perspective view showing a turning tool 1 according to an embodiment of the present invention attached to a holder 80. FIG. 2 is a perspective view of the turning tool 1. FIG. 3 is a perspective development view showing the component configuration of the turning tool 1. FIG. 4 is a side view of the turning tool 1. FIG. 5 is a view of the turning tool 1 as seen from one side Dj1 in the axial direction Dj. As shown in FIG. 1, a turning tool 1 is attached to a holder 80 when in use. The holder 80 is mounted on a turret 202 of a turret lathe, which serves as a machine tool 200. The turret 202 is rotatable around its central axis. A plurality of holders 80 are mounted on the outer periphery of the turret 202 at intervals in the circumferential direction. By rotating the turret 202, the machine tool 200 appropriately selects one of the turning tools 1 held in each of the plurality of holders 80 and moves it to a position facing a workpiece 100 (see FIGS. 5 and 6), thereby performing cutting processing on the workpiece 100.

[0020] The turning tool 1 of this embodiment performs turning, such as boring, on a workpiece 100, such as a metal material, which is rotated around a spindle of a machine tool 200. As shown in FIGS. 2 to 5 , the turning tool 1 of this embodiment is made of metal and includes a tool body 2 and a cutting insert 4.

[0021] The tool body 2 extends in an axial direction Dj along the tool axis J. The tool body 2 has a head portion 21 provided on one side Dj1 of the tool body 2 in the axial direction Dj, and an attachment portion 22 provided at a base end portion of the head portion 21 on the other side Dj2 in the axial direction Dj.

[0022] The head portion 21 extends from the attachment portion 22 to one side Dj1 in the axial direction Dj along the tool axis J. The head portion 21 has a generally polygonal columnar shape when viewed in the axial direction Dj. The head portion 21 may have a circular columnar shape when viewed in the axial direction Dj. A pedestal 24 is provided on one side Dr1 in the radial direction Dr that intersects with the tool axis J of the outer peripheral surface 23 of the head portion 21 when viewed in the axial direction Dj. The pedestal 24 is formed so as to be recessed inward in the radial direction Dr from the outer peripheral surface 23. The cutting insert 4 is held on the pedestal 24 via a seat member 41.

[0023] In this embodiment, the mounting portion 22 has a disk shape that expands in diameter outward in the radial direction Dr relative to the head portion 21. A plurality of through holes 22h are formed in the mounting portion 22, more outward in the radial direction Dr than the head portion 21. As shown in Fig. 1, the mounting portion 22 is detachably fixed to the holder 80 by a plurality of mounting screws 27 that are inserted into the through holes 22h.

[0024] The cutting insert 4 is disposed on one side of the tool body 2 in the radial direction Dr with respect to the tool axis J. As shown in FIG. 3, the cutting insert 4 and the seat member 41 are rhombic when viewed in the thickness direction. The cutting insert 4 has a pair of rhombic main surfaces in a plan view facing the thickness direction and side surfaces connecting the pair of main surfaces. A cutting edge 42 is provided on a ridge between the main surfaces and the side surfaces of the cutting insert 4. As shown in FIG. 4, the cutting edge 42 is provided at a tip end portion of one side Dj1 in the axial direction Dj of the head portion 21. A portion of the cutting edge 42 protrudes from the head portion 21 to the one side Dj1 in the axial direction Dj. Furthermore, as shown in FIG. 5, the cutting edge 42 protrudes outward in the radial direction Dr of the head portion 21. Therefore, a portion of the cutting edge 42 is located at the forefront of the one side Dj1 in the axial direction Dj of the head portion 21 and at the outermost end in the radial direction Dr.

[0025] As shown in FIG. 3 , through-holes 4h, 41h are formed in the central portions of the cutting insert 4 and the seat member 41, respectively, penetrating the cutting insert 4 and the seat member 41 in the thickness direction. The cutting insert 4 and the seat member 41 are detachably attached to the tool body 2 by a clamp member 5. The clamp member 5 in this embodiment is made of a metal material such as steel, and is formed so that, in a plan view, the rear end is wide and the front end becomes narrower toward the front end. A protruding wall portion 5a is formed on the upper portion of the clamp member 5 in the central portion between the rear end and the front end, and has a front wall surface that protrudes upward in a convex curved shape toward the rear end. A through-hole 5h is formed on the rear end side of the protruding wall portion 5a of the clamp member 5, penetrating the clamp member 5 vertically. A locking claw 5s is formed at the front end of the clamp member 5, protruding downward. A protrusion 5t (see FIG. 4 ) is formed at the rear end of the clamp member 5, protruding downward.

[0026] A clamp fixing surface 25 is formed on the head portion 21. The clamp fixing surface 25 is recessed inward from the outer peripheral surface 23 in the radial direction Dr and is formed approximately parallel to the seat surface 24f of the base 24. The clamp member 5 is fixed to the clamp fixing surface 25 by a fixing screw 52 with the seat member 41 and the cutting insert 4 sandwiched between the clamp member 5 and the base 24. At this time, the locking claws 5s of the clamp member 5 are inserted into the through hole 4h of the cutting insert 4 and the through hole 41h of the seat member 41. The protrusion 5t of the clamp member 5 is inserted into the recess 23b formed on the outer peripheral surface 23 of the head portion 21 and determines the orientation of the clamp member 5 around the fixing screw 52. The fixing screw 52 is threaded through the through hole 5h of the clamp member 5 and into the female screw hole 24h formed in the seat surface 24f of the base 24.

[0027] A holder member 7 is provided at a tip end of the head portion 21 on one side Dj1 in the axial direction Dj. The holder member 7 is arranged on the other side of the radial direction Dr with respect to the tool axis J in the tool body 2. That is, the holder member 7 is arranged on the opposite side of the tool axis J from the cutting insert 4 attached to the base 24 in the radial direction Dr of the tool body 2. The holder member 7 is fitted into a recess 21b formed at the tip end of the head portion 21, and is arranged so that a holder tip surface 7f facing one side Dj1 in the axial direction Dj is continuous with the tip surface of the head portion 21. The holder member 7 is detachably attached to the head portion 21 via a mounting screw 72.

[0028] The tool body 2 is provided with an axial distance sensor 31 and a radial distance sensor (distance sensor) 32. In this embodiment, the axial distance sensor 31 and the radial distance sensor 32 measure the distance to a machined surface 100m of a workpiece 100 machined using the cutting insert 4. In this embodiment, the axial distance sensor 31 and the radial distance sensor 32 are eddy current sensors.

[0029] The axial distance sensor 31 and the radial distance sensor 32 have their respective tip surfaces 31a and 32a facing the object to be measured. The axial distance sensor 31 and the radial distance sensor 32 generate a high-frequency magnetic field by passing a high-frequency current through them. This causes eddy currents to flow on the surface (machined surface) of the object to be measured, which is a conductor, and changes the impedance of the coils inside the axial distance sensor 31 and the radial distance sensor 32. The axial distance sensor 31 and the radial distance sensor 32 detect the distance to the machined surface, which is the object to be measured, from this change in impedance. Eddy current sensors tend to maintain stable measurement accuracy despite disturbances such as those in the surrounding environment. Therefore, eddy current sensors are more suitable for distance measurement in a disturbance-prone environment after cutting, regardless of whether wet or dry cutting is selected, compared to optical distance sensors, for example.

[0030] The axial distance sensor 31 is inserted and held in a sensor holding hole 7h formed in the holder member 7. The sensor holding hole 7h penetrates the holder member 7 in the axial direction Dj. A tip end surface 31a of the axial distance sensor 31 is arranged facing one side Dj1 of the axial direction Dj. In this way, the axial distance sensor 31 is arranged on the opposite side of the tool axis J from the cutting insert 4 attached to the base 24 in the radial direction Dr of the tool body 2. The axial distance sensor 31 measures the distance to a measurement object arranged on one side Dj1 of the axial direction Dj of the tool body 2. That is, the measurement direction of the axial distance sensor 31 is one side Dj1 of the axial direction Dj. The axial distance sensor 31 measures the distance to a machined surface machined by the cutting insert 4 and facing the other side Dj2 of the axial direction Dj.

[0031] As shown in Fig. 4, the radial distance sensor 32 is provided at a position overlapping with the cutting insert 4 in the axial direction Dj. As shown in Fig. 5, the radial distance sensor 32 is arranged at a position different from the cutting insert 4 in the circumferential direction around the tool axis J as viewed from the axial direction Dj. The radial distance sensor 32 is arranged on the rear side of the cutting insert 4 in the relative rotation direction R with respect to the workpiece 100.

[0032] The radial distance sensor 32 is provided such that, when viewed from the axial direction Dj, the sensor axis 32c is inclined with respect to a line L connecting the tool axis J and the cutting edge 42 of the cutting insert 4. The inclination angle α between the line L connecting the tool axis J and the cutting edge 42 of the cutting insert 4 and the sensor axis 32c is expressed as follows: 0°<α<90° Furthermore, the tilt angle α is set as follows: 5°<α<45° It is preferable to set the inclination angle α so that it satisfies the following range. 10°<α<30° is. It is preferable to make the inclination angle α as small as possible and to bring the radial distance sensor 32 as close as possible to the cutting insert 4 in the circumferential direction. Meanwhile, the fixing screw 52 and its female screw hole 24h (see FIG. 3) are provided around the cutting insert 4. Therefore, it is preferable to set the inclination angle α so as to avoid interference between the radial distance sensor 32 and the fixing screw 52 and its female screw hole 24h.

[0033] As shown in Fig. 3, the radial distance sensor 32 is inserted and held in a sensor holding hole 21h formed in the head part 21. As shown in Fig. 5, a tip surface 32a of the radial distance sensor 32 is disposed facing outward in the radial direction Dr from the outer peripheral surface 23 of the head part 21. The tip surface 32a of the radial distance sensor 32 is provided so as to be flush with the outer peripheral surface 23s at a position where the tip of the radial distance sensor 32 is provided, on the outer peripheral surface 23 of the head part 21 which is continuous in the circumferential direction around the tool axis J with respect to the base 24.

[0034] The radial distance sensor 32 is preferably provided so that the sensor axis 32c extends in a direction perpendicular to the tangent direction K of the outer peripheral surface 23s at the position where the tip of the radial distance sensor 32 is provided. Here, the direction perpendicular to the tangent direction K of the outer peripheral surface 23s includes a range of approximately 90±10° with respect to the tangent direction of the outer peripheral surface 23s.

[0035] The radial distance sensor 32 measures the distance to a measurement object that is located outside the radial direction Dr of the tool body 2. That is, the radial distance sensor 32 measures the distance to the outside of the radial direction Dr. The radial distance sensor 32 measures the distance to the machined surface that is machined by the cutting insert 4 and faces inward in the radial direction Dr.

[0036] FIG. 6 is a diagram showing a state in which the radial distance sensor 32 of the turning tool 1 measures up to 100 m of the machined surface of the workpiece 100. In FIG. As shown in Figure 6, to machine a workpiece 100 using such a turning tool 1, the workpiece 100 is chucked in a chuck portion (not shown) of a machine tool 200 (see Figure 1), and while the workpiece 100 is rotated around the spindle of the machine tool 200, the cutting blade 42 is brought into contact with an inner peripheral surface 101 of the workpiece 100 and moved axially. Furthermore, the machine tool 200 machines a step surface 102 extending radially inward from the inner peripheral surface 101. At this time, the machine tool 200 moves the cutting blade 42 radially while continuing to rotate the workpiece 100 around the spindle.

[0037] Thereafter, the machined surface 100m of the workpiece 100 is measured. To do this, the axial distance sensor 31 is brought close to the step surface 102, which is part of the machined surface 100m, in the axial direction Dj, and the distance to the workpiece 100 is measured. Also, as shown in Figures 5 and 6, the radial distance sensor 32 is brought close to the inner circumferential surface 101, which is part of the machined surface 100m, in the radial direction Dr, and the distance to the workpiece 100 is measured.

[0038] [Effects of this embodiment] According to the turning tool 1 of the present embodiment described above, the radial distance sensor 32 is provided with the sensor axis 32c inclined at an inclination angle α satisfying 0°<α<90° with respect to the line L connecting the tool axis J and the cutting edge 42 of the cutting insert 4, as viewed from the axial direction Dj. Therefore, the cutting insert 4 and the radial distance sensor 32 are arranged on the same side in the radial direction Dr with respect to the tool axis J. This allows the radial distance sensor 32 to be brought close to the machined surface 100m of the workpiece 100 machined by the cutting insert 4, regardless of the structure of the machine tool 200, the inner diameter of the machined surface 100m, etc. Therefore, by bringing the radial distance sensor 32 close to the machined surface 100m, it is possible to measure the distance to the machined surface 100m with high accuracy.

[0039] Furthermore, in this embodiment, the radial distance sensor 32 is provided on the outer peripheral surface 23 of the head unit 21 so that the sensor axis 32c extends in a direction perpendicular to the tangent direction K of the outer peripheral surface 23s at the position where the tip of the radial distance sensor 32 is provided, thereby preventing the sensor axis 32c from tilting with respect to the machining surface 100m. This prevents a large difference in the distance to the machining surface 100m between one side and the other side in the circumferential direction of the radial distance sensor 32. This prevents a decrease in the measurement accuracy of the distance to the machining surface 100m.

[0040] In addition, in this embodiment, the radial distance sensor 32 is located in a position that avoids interference with the fixing screw 52 that fixes the cutting insert 4 to the head portion 21. Therefore, even if the fixing screw 52 is attached or detached when replacing the cutting insert 4, the fixing screw 52 can be prevented from hitting the radial distance sensor 32 and causing positional deviation, etc.

[0041] Furthermore, in this embodiment, the inclination angle α is 10°<α<30°, so the radial distance sensor 32 can be disposed in a position close to the cutting insert 4 while avoiding interference with the fixing screw 52 that fixes the cutting insert 4 to the head portion 21. Therefore, the radial distance sensor 32 can be more reliably brought close to the machined surface 100m of the workpiece 100 machined by the cutting insert 4, and the distance to the machined surface 100m can be measured with high accuracy.

[0042] In addition, in this embodiment, in a turret-type machine tool 200, the radial distance sensor 32 can be brought close to the machining surface 100m of the workpiece 100 machined by the cutting insert 4, so that the distance to the machining surface 100m can be measured with high accuracy.

[0043] [Other configurations included in the present invention] The present invention is not limited to the above-described embodiment, and the configuration can be changed within the scope of the present invention, as will be described below.

[0044] In the above-described embodiment, the attachment portion 22 is disk-shaped, but is not limited to this. The attachment portion 22 may be shaped like a shaft extending in the axial direction Dj. Furthermore, although a turret lathe has been exemplified as machine tool 200, the present invention is not limited to this. Machine tool 200 may be, for example, a multi-tasking machine or the like.

[0045] Furthermore, the configurations (elements) described in the above-described embodiments, modifications, and notes may be combined without departing from the spirit of the present invention, and additions, omissions, substitutions, and other modifications of the configurations are possible. Furthermore, the present invention is not limited to the above-described embodiments, but is limited only by the claims. [Explanation of symbols]

[0046] 1...Turning tool 2…Tool body 4...Cutting insert 21...Head 22...Mounting part 23...Outer surface 23s…Outer surface 24...Pedestal 32...Radial distance sensor (distance sensor) 32c...Sensor axis 42...Cutting edge 52...Fixing screw 80...Holder 100…Work material 100m…processed surface 200…Machine tools 202...Turret 100…Work material J…Tool axis α…Inclination angle

Claims

1. a tool body including a head portion extending along a tool axis and having a seat at a tip end portion on one side in an axial direction along the tool axis, and an attachment portion provided at a base end portion on the other side in the axial direction relative to the head portion; a cutting insert detachably attached to the base; a distance sensor provided in the tool body for detecting a distance to a machined surface of a workpiece machined by the cutting insert, The distance sensor The cutting insert is provided at a position overlapping the cutting insert in the axial direction, When viewed from the axial direction, the sensor axis is inclined at an inclination angle α of 0°<α<90° with respect to a line connecting the tool axis and the cutting edge of the cutting insert. Turning tools.

2. the distance sensor is provided on an outer peripheral surface of the head portion, which is continuous with the base in a circumferential direction around the tool axis, such that the sensor axis extends in a direction perpendicular to a tangent direction of the outer peripheral surface at a position where a tip end of the distance sensor is provided.

2. The turning tool of claim 1.

3. The distance sensor is provided at a position that avoids interference with a fixing screw that fixes the cutting insert to the head portion.

3. A turning tool according to claim 1 or 2.

4. The inclination angle α is 10°<α<30°.

3. A turning tool according to claim 1 or 2.

5. The mounting portion is fixable to a holder attached to a turret of a machine tool.

3. A turning tool according to claim 1 or 2.

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