Tool changing arm and method for adjusting tool changing arm

Abstract

The present invention provides a tool changing arm with little misalignment between a tool holding part of the tool changing arm and a spindle. Provided is a tool changing arm for changing a tool on a spindle of a machine tool, the tool changing arm comprising: a base part; a turning part supported on the base part so as to be able to turn about a turning axis parallel to a spindle center axis, which is the center of rotation center of the spindle; a tool holding part attached to the turning part and capable of holding a tool in an orientation such that a tool center axis, which is the center of rotation of the tool, is parallel to the spindle center axis; an abutting part provided on either the tool holding part or the turning part and disposed so as to contact the turning part or the tool holding part when the tool holding part moves in a rotational direction centered on the tool center axis in a state in which the spindle center axis is aligned with the tool center axis while the tool holding part is holding the tool; and a securing part that secures the tool holding part and the turning part in the state with the abutting part contacting the turning part or the tool holding part.

Description

Tool change arm and tool change arm adjustment method

[0001] The present disclosure relates to a tool change arm and a method for adjusting a tool change arm.

[0002] A known automatic tool changer for a machine tool includes a spindle that rotates with a tool attached thereto, and a tool change arm that attaches and detaches the tool to and from the spindle. The tool change arm includes a base, a swivel that is rotatable relative to the base about a pivot that is parallel to the spindle central axis that is the center of rotation of the spindle, and a tool gripper that is attached to the swivel.

[0003] Known tool gripping sections of tool change arms include those configured to rotate around a rotation axis perpendicular to the rotation axis of the swivel section to move the gripped tool closer to and away from the spindle (see, for example, Patent Document 1), and those configured to rotate around the rotation axis of the swivel section to move the gripped tool closer to and away from the spindle (see, for example, Patent Documents 2 and 3).

[0004] Japanese Patent Application Laid-Open No. 2020-192678 Japanese Patent Application Laid-Open No. 2016-43466 Japanese Patent Application Laid-Open No. 2021-133472

[0005] Accumulation of errors in the component precision and assembly precision of the tool change arm and the spindle can cause misalignment between the tool change arm and the spindle. If misalignment occurs between the tool change arm and the spindle, the tool central axis of the tool held by the tool gripping unit may be misaligned with the spindle central axis when transferring a tool between the tool gripping unit and the spindle, which may result in wear on the spindle and the tool or failure to transfer the tool. Therefore, it is desirable to minimize the misalignment between the tool central axis of the tool held by the tool gripping unit and the spindle central axis during tool replacement.

[0006] A commonly known method for reducing the misalignment between the tool central axis and the spindle central axis during tool change involves measuring the misalignment between the gripping axis of the tool gripping unit (the axis that coincides with the tool central axis of the tool gripped in the tool gripping unit) and the spindle central axis, and adjusting the position of the base of the tool change arm based on the measured value. However, this method requires measuring the amount of misalignment and adjusting the position of the base based on the measurement results, which takes time for the adjustment work.

[0007] An object of the present disclosure is to provide a tool change arm with a small positional misalignment between the tool gripping portion of the tool change arm and the spindle, and a method for adjusting the tool change arm that can reduce the positional misalignment between the tool gripping portion of the tool change arm and the spindle.

[0008] One aspect of the present disclosure is a tool change arm that changes tools for a spindle of a machine tool, the tool change arm comprising: a base portion; a swivel portion supported relative to the base portion so as to be rotatable about a pivot axis that is parallel to a spindle central axis that is the center of rotation of the spindle; a tool gripping portion attached to the swivel portion and capable of gripping the tool in an attitude in which the tool central axis that is the center of rotation of the tool is parallel to the spindle central axis; a stop portion provided on either the tool gripping portion or the swivel portion and arranged to come into contact with the swivel portion or the tool gripping portion when the tool gripping portion moves in a rotational direction about the tool central axis with the spindle central axis and the tool central axis when the tool gripping portion grips the tool aligned; and a fixing portion that fixes the tool gripping portion and the swivel portion in a state in which the stop portion comes into contact with the swivel portion or the tool gripping portion.

[0009] One aspect of the present disclosure is a method for adjusting a tool change arm that changes tools for a spindle of a machine tool, the tool change arm including: a base; a swivel supported relative to the base so as to be rotatable about a pivot axis parallel to a spindle central axis that is the center of rotation of the spindle; and a tool gripping unit attached to the swivel, capable of gripping the tool in an attitude in which the tool central axis that is the center of rotation of the tool is parallel to the spindle central axis, the method comprising: a first step of positioning the tool gripping unit at a position where the spindle central axis and the tool central axis when the tool gripping unit grips the tool coincide with each other; a second step of moving the tool gripping unit in a rotational direction about the spindle central axis to a position of the swivel unit to adjust its attachment position with respect to the swivel unit; and a third step of fixing the tool gripping unit that has been moved to the position of the swivel unit and the swivel unit.

[0010] 4 is a perspective view showing a tool change arm and a spindle according to the first embodiment; FIG. 5 is a plan view showing a fixing portion of the swivel portion of the tool change arm shown in FIG. 1; FIG. 6 is a cross-sectional view taken along line A-A in FIG. 2; FIG. 7 is a perspective view of the tool gripping portion shown in FIG. 1; FIG. 8 is an enlarged perspective view of the chuck portion of the tool gripping portion shown in FIG. 4; FIG. 9 is a front view showing an example of a tool; FIG. 10 is a view showing a first step in the method for adjusting a tool change arm according to the first embodiment; FIG. 11 is a plan view showing the start of a second step in the method for adjusting a tool change arm according to the first embodiment; FIG. 12 is a plan view showing the end of the second step in the method for adjusting a tool change arm according to the first embodiment; FIG. 13 is an enlarged plan view showing the fixing portion between the swivel portion and the tool gripping portion at the end of the second step in the method for adjusting a tool change arm according to the first embodiment; FIG. 14 is a perspective view showing a tool change arm according to the second embodiment; FIG. 15 is a perspective view of a tool change arm according to a third embodiment as viewed from below; FIG. 16 is a bottom view showing the tool change arm at the end of the second step in the method for adjusting a tool change arm according to the third embodiment; FIG. 17 is a perspective view showing a tool change arm according to a fourth embodiment;

[0011] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. FIG. 1 shows a tool change arm 1 and a spindle unit 100 according to a first embodiment. The spindle unit 100 has a spindle 101 that rotates by driving a motor (not shown). A tool 200 is detachably attached to the lower end of the spindle 101. The spindle 101 performs various machining operations on a workpiece (not shown) by rotating the tool 200. In the following description, a spindle center axis J1, which is the center of rotation of the spindle 101, is assumed to be disposed along the vertical direction (the up-down direction in FIG. 1 ), but the direction of the spindle center axis J1 is not limited.

[0012] The tool change arm 1 constitutes a part of the tool changer. More specifically, the tool change arm 1 constitutes a part of an automatic tool changer (ATC) that automatically exchanges a gripped tool 200 with a tool 200 attached to a spindle 101. The tool change arm 1 is disposed to the side of the spindle unit 100 and is fixed to the tool changer while being positioned relative to the spindle unit 100. The tool change arm 1 is constituted by a base portion 2, a swivel portion 3, and a tool gripper portion 4.

[0013] The base 2 is a box-shaped body and is mounted on the tool changer so that it can be raised and lowered in the vertical direction by a lifting mechanism (not shown). The direction of the lifting movement of the base 2 is parallel to the spindle central axis J1. A motor (not shown) is housed inside the base 2.

[0014] The swivel unit 3 has a rotary shaft unit 31 and a mounting plate unit 32, and is supported by the base unit 2. The rotary shaft unit 31 extends vertically downward from the underside of the base unit 2. The rotary shaft unit 31 is connected to the output shaft of a motor (not shown) housed in the base unit 2. Driven by the motor of the base unit 2, the rotary shaft unit 31 can rotate clockwise and counterclockwise relative to the base unit 2 around a rotary axis J2, which is the central axis of the rotary shaft unit 31. The rotary axis J2 is disposed along the length direction of the rotary shaft unit 31 and parallel to the main spindle central axis J1.

[0015] The mounting plate 32 is attached to the lower end 31a of the rotating shaft 31 with bolts (not shown). More specifically, the mounting plate 32 is attached to the lower end 31a of the rotating shaft 31 with its flat surface facing up and down. This allows the mounting plate 32 to rotate clockwise and counterclockwise around the rotation axis J2 as the rotating shaft 31 rotates. The mounting plate 32 has a pair of fixing portions 321, 321 extending in opposite directions with the rotating shaft 31 in between. Note that, although the mounting plate 32 is plate-shaped in this embodiment, it is not limited thereto and may be a non-plate-shaped portion having fixing portions.

[0016] The fixing portions 321, 321 are fixed to the two tool gripping portions 4, 4 described below. As shown in Fig. 2, the side surface of the fixing portion 321 has a tip peripheral surface 321a which is the peripheral surface farthest from the rotating shaft portion 31, and a pair of side peripheral surfaces 321b, 321b extending from the rotating shaft portion 31 toward both ends of the tip peripheral surface 321a. The side peripheral surfaces 321b, 321b are connected to both ends of the tip peripheral surface 321a. The direction D1 indicated by the arrow in Fig. 2 indicates the direction in which the fixing portion 321 extends (moves away) from the rotating shaft portion 31, and the direction D2 indicates the opposite direction to the direction D1.

[0017] As shown in FIG. 2 , four bolt insertion holes 322 are formed in the fixing portions 321, 321. The bolt insertion holes 322 are holes through which bolts 300 for fixing the tool gripping portion 4 (described later) are inserted. As shown in FIG. 3 , the bolt insertion holes 322 are stepped holes having, in order from the top surface 32a of the mounting plate portion 32, a large diameter portion 322a and a small diameter portion 322b. The large diameter portion 322a and the small diameter portion 322b are formed concentrically and continuously in the thickness direction of the mounting plate portion 32. The inner diameter of the large diameter portion 322a is larger than the outer diameter of the head portion 301 of the bolt 300 (see FIG. 11 ). The inner diameter of the small diameter portion 322b is smaller than the outer diameter of the head portion 301 of the bolt 300 and larger than the outer diameter of the bolt shank 302 (see FIG. 11 ). Therefore, the head 301 and the bolt shank 302 of the bolt 300 can be loosely inserted into the bolt insertion hole 322 with a gap that allows their positions to be adjusted in the radial direction.

[0018] The tool gripping unit 4 is attached to the swivel unit 3 by the fixing portions 321 of the mounting plate 32 of the swivel unit 3. The tool gripping unit 4 is attached to each of the pair of fixing portions 321, 321 of the mounting plate 32. Therefore, as shown in FIG. 1 , two tool gripping units 4, 4 are attached to the swivel unit 3 of this embodiment. The two tool gripping units 4, 4 have the same configuration except that they extend in opposite directions (180 degrees apart) from the mounting plate 32. Therefore, the configuration of one tool gripping unit 4 will be described below.

[0019] As shown in Fig. 4, the tool gripping unit 4 has a support base 41 and a rotating unit 42. The support base 41 is a block-shaped portion that mounts the tool gripping unit 4 to the fixed portion 321 of the mounting plate 32 of the swivel unit 3. The upper surface of the support base 41 is a rectangular flat surface that forms a mounting surface 41a for the fixed portion 321. The mounting surface 41a is provided with four bolt holes 411 that are arranged to correspond to the four bolt insertion holes 322 of the fixed portion 321. The inner surfaces of the bolt holes 411 are each formed with a female thread that screws into the male thread on the outer periphery of the bolt shank 302 of the bolt 300.

[0020] The mounting surface 41a is provided with one abutment portion 412. In this embodiment, the abutment portion 412 is a single cylindrical protrusion that protrudes upward from the mounting surface 41a. The abutment portion 412 is arranged on the D1 direction side, which is the extension direction of the fixed portion 321 from the rotating shaft portion 31, with respect to the four bolt holes 411 in the mounting surface 41a. More specifically, the abutment portion 412 is arranged between one edge portion 41b on the D1 direction side of the four edge portions that form the outer periphery of the mounting surface 41a and the four bolt holes 411.

[0021] The abutment portion 412 of the tool gripping unit 4 comes into contact with the tip peripheral surface 321a of the mounting plate portion 32 of the swivel unit 3 from the direction D2. Because the abutment portion 412 has a cylindrical shape, it abuts on an arcuate surface against the tip peripheral surface 321a of the mounting plate portion 32. Therefore, the abutment portion 412 comes into line contact with the tip peripheral surface 321a of the mounting plate portion 32 along a direction parallel to the rotation axis J2 of the swivel unit 3, which is the protruding direction of the abutment portion 412. This ensures that the tool gripping unit 4 is positioned with respect to the swivel unit 3.

[0022] The abutment portion 412 is provided on the mounting surface 41a at a position where the bolt holes 411 formed in the mounting surface 41a of the tool gripping unit 4 are located, inside the bolt insertion holes 322 formed in the fixed portion 321 of the mounting plate 32 when in contact with the tip peripheral surface 321a of the mounting plate 32 (see FIG. 10 ). The support base 41 is attached to the fixed portion 321 with four bolts 300 inserted through the four bolt insertion holes 322 of the fixed portion 321, with the mounting surface 41a butted against the underside of the fixed portion 321 and the abutment portion 412 in contact with the mounting plate 32 of the swivel unit 3.

[0023] The rotating unit 42 integrally includes a base 421 attached to the support base 41, a tip end 422 extending away from the support base 41 relative to the base 421, and a chuck 423 for detachably gripping the tool 200. The base 421 is attached to the support base 41 so as to be rotatable about a rotation axis J5 by driving a motor (not shown). The rotation axis J5 is an axis perpendicular to the rotation axis J2 of the rotating unit 3 and is arranged parallel to the D1 direction and the D2 direction as shown in FIG. 4. The base 421 and the tip end 422 are bent at an obtuse angle. The chuck 423 is provided at the tip of the tip end 422.

[0024] As shown in Figures 4 and 5, the chuck portion 423 has gripping arms 423a, 423a that are bifurcated into a U-shape from a tip portion 422. The inside of the gripping arms 423a, 423a is formed in an arc shape to fit the outer periphery of the tool 200 to be gripped. As shown in Figure 5, an arc-shaped convex portion 423b is formed on the inside of the gripping arms 423a, 423a. As shown in Figure 6, the convex portion 423b is formed to fit into an annular recess 201 formed on the outer periphery of the tool 200. At the tips of the gripping arms 423a, 423a, holding protrusions 423c, 423c that fit into the recess 201 of the tool 200 to hold the tool 200 are provided facing each other.

[0025] The chuck portion 423 grips the tool 200 by fitting the convex portion 423b into the concave portion 201 of the tool 200 and fitting the holding protrusions 423c, 423c into the concave portion 201 of the tool 200 to hold the tool 200. When the tool 200 is gripped, the gripping axis J3 of the tool gripping portion 4 coincides with the tool central axis J4, which is the center of rotation of the tool 200.

[0026] The rotating unit 42 rotates about the rotation axis J5 to move the gripped tool 200 toward and away from the spindle 101. Figures 1 and 4 show a state in which the rotating unit 42 has rotated about the rotation axis J5 so that the chuck portion 423 side is positioned at the uppermost position. The tip end 422 is positioned approximately horizontally. At this time, the tool gripping unit 4 has an orientation in which the tool center axis J4 of the gripped tool 200 and the spindle center axis J1 of the spindle 101 are parallel to each other.

[0027] Next, an adjustment method for attaching the tool gripping portion 4 of the tool exchange arm 1 according to the first embodiment to the swivel portion 3 will be described with reference to FIGS.

[0028] 7, the base unit 2 and the swivel unit 3 are raised and on standby. At this time, the base unit 2 and the swivel unit 3 are positioned so that the tool 200 held by the tool gripping unit 4 is attached to the spindle 101, or so that the tool gripping unit 4 grips the tool 200 attached to the spindle 101. In this state, the tool gripping unit 4, with the tool 200 held by the chuck 423, is positioned so that the spindle central axis J1 and the tool central axis J4 coincide with each other (first step).

[0029] More specifically, the tool gripping unit 4 gripping the tool 200 is moved upward as indicated by the outline arrow in Figure 7, and the tool 200 is attached to the spindle 101. As a result, the tool central axis J4 of the tool 200 gripped by the tool gripping unit 4 coincides with the spindle central axis J1.

[0030] As another example, the tool 200 may be attached to the spindle 101 in advance. In this case, the chuck portion 423 of the tool gripping unit 4 is brought close to the tool 200 attached to the spindle 101, thereby causing the chuck portion 423 to grip the tool 200. That is, in the first step, the tool 200 is gripped by the spindle 101 and the tool gripping unit 4, thereby positioning the tool gripping unit 4 at a position where the spindle central axis J1 and the tool central axis J4 coincide with each other.

[0031] 8 and 9, the tool gripping part 4, which grips the tool 200 attached to the spindle 101, is then moved in the rotational direction about the spindle central axis J1 to the position of the swivel part 3. This adjusts the horizontal attachment position of the tool gripping part 4 relative to the swivel part 3 (second step).

[0032] In Fig. 8, the tool gripping unit 4 is rotated clockwise in a plan view around the spindle central axis J1. As a result, as shown in Fig. 9, the mounting surface 41a of the support base 41 of the tool gripping unit 4 is positioned so as to face the underside of the fixed portion 321 of the mounting plate 32 of the swivel unit 3, and the fixed portion 321 of the swivel unit 3 and the support base 41 of the tool gripping unit 4 are positioned so as to overlap one another vertically.

[0033] When the tool gripping part 4 rotates around the spindle central axis J1, an abutment part 412 protruding from the mounting surface 41a of the tool gripping part 4 abuts against and makes line contact with the tip peripheral surface 321a of the fixed part 321. This positions the tool gripping part 4 with respect to the swivel part 3. At this time, as shown in Figure 10, four bolt holes 411 opening into the mounting surface 41a of the tool gripping part 4 are positioned inside four bolt insertion holes 322 provided in the fixed part 321.

[0034] The swivel unit 3 of the tool change arm 1 is attached in advance to an appropriate position relative to the spindle unit 100 so that the gripping axis J3 of the tool gripping unit 4 and the spindle center axis J1 of the spindle 101 coincide with each other. However, due to accumulated errors in component accuracy and assembly accuracy, misalignment may occur between the swivel unit 3 and the spindle unit 100. This may result in misalignment between the gripping axis J3 of the tool gripping unit 4 and the spindle center axis J1 of the spindle 101. Figure 10 shows a state in which a misalignment has occurred between the gripping axis J3 of the tool gripping unit 4 and the spindle center axis J1 of the spindle 101. In this state, the bolt insertion hole 322 of the fixing portion 321 and the bolt hole 411 of the tool gripping unit 4 are not concentrically arranged but are slightly misaligned.

[0035] Next, the tool gripping portion 4 is moved to the position of the swivel portion 3 and positioned by the abutment portion 412, and then the swivel portion 3 is fixed (third step).

[0036] 11 , the bolts 300 are threaded through the bolt insertion holes 322 of the fixing part 321 and into the bolt holes 411 of the tool gripping part 4. The bolt insertion holes 322 can loosely accommodate the head 301 and the bolt shank 302 of the bolt 300. Therefore, even if the bolt insertion holes 322 and the bolt holes 411 are misaligned due to misalignment between the swivel part 3 and the spindle 101, the bolts 300 can be threaded through the bolt insertion holes 322 into the bolt holes 411.

[0037] As a result, the tool gripping unit 4 is fixed to the fixing portion 321 of the swivel unit 3. The tool gripping unit 4 is fixed to the swivel unit 3 with the spindle central axis J1, the gripping axis J3, and the tool central axis J4 aligned, so that positional deviation with respect to the spindle 101 caused by errors in component accuracy and assembly accuracy can be reduced without the need for tedious adjustment work.

[0038] 12 is a plan view showing a tool exchange arm 1A according to the second embodiment. Since parts having the same reference numerals as those in the tool exchange arm 1 according to the first embodiment have the same configuration, their description will be omitted below.

[0039] The tool gripping unit 4 of this tool change arm 1A has a butt portion 413 that protrudes upward in a wall-like manner from the mounting surface 41a of the support base 41, instead of the cylindrical butt portion 412 of the tool gripping unit 4 of the tool change arm 1 according to the first embodiment. The butt portion 413 extends across the entire width of the mounting surface 41a. The surface 413a of the butt portion 413 that faces the mounting plate 32 is formed in an arc shape that curves horizontally. When the tool gripping unit 4 is moved in the rotational direction around the spindle central axis J1 (gripping axis J3) to the position of the swivel unit 3 in the second step, the butt portion 413 makes line contact with the tip peripheral surface 321a of the mounting plate 32 from the direction D2, similar to the cylindrical butt portion 412. Therefore, this tool change arm 1A can reliably position the tool gripping unit 4, similar to the tool change arm 1.

[0040] 13 and 14 are plan views showing a tool change arm 1B according to the third embodiment. Since parts with the same reference numerals as those in the tool change arm 1 according to the first embodiment have the same configuration, their description will be omitted below.

[0041] The tool gripping unit 4 of this tool change arm 1B does not have an abutment portion, but has an abutment portion 323 provided on the swivel unit 3. The abutment portion 323 protrudes downward from the lower surface 321c of the fixed portion 321 of the mounting plate portion 32 of the swivel unit 3. The abutment portion 323 may be formed in a cylindrical shape similar to the abutment portion 412 of the tool change arm 1 according to the first embodiment, or may be formed to protrude in a wall shape similar to the abutment portion 413 provided on the tool change arm 1A according to the second embodiment. When the tool gripping unit 4 is moved in the rotational direction about the spindle central axis J1 (gripping axis J3) to the position of the swivel unit 3 in the second step, the abutment portion 323 comes into line contact with the side surface 41c of the support base portion 41 of the tool gripping unit 4 from the direction D1. Therefore, like the tool change arm 1, this tool change arm 1B can reliably position the tool gripping unit 4.

[0042] 15 is a plan view showing a tool change arm 1C according to the fourth embodiment. Since parts with the same reference numerals as those in the tool change arm 1 according to the first embodiment have the same configuration, their description will be omitted below.

[0043] This tool change arm 1C has a tool gripping portion 4A disposed on a fixed portion 321 of the mounting plate portion 32 of the swivel portion 3 and arranged parallel to the fixed portion 321. The tool gripping portion 4A extends in a direction away from the fixed portion 321 along the extension direction of the fixed portion 321 from the rotating shaft portion 31. A chuck portion 431 for gripping a tool 200 is formed at the end of the tool gripping portion 4A farthest from the fixed portion 321. The tool gripping portion 4A is fixed to the fixed portion 321 by a bolt 300 (not shown in FIG. 15 ) inserted through a bolt insertion hole 322 of the fixed portion 321, with an upper surface 43 a of the end portion closest to the rotating shaft portion 31 abutting against the lower surface of the fixed portion 321. This tool gripping portion 4A is configured to move the tool 200 gripped by the chuck portion 431 toward and away from the spindle 101 as the rotary shaft portion 31 of the swivel portion 3 rotates.

[0044] An abutment portion 432 is formed on the upper surface 4a of the tool gripping portion 4A. The abutment portion 432 protrudes upward from the upper surface 4a of the tool gripping portion 4A. The abutment portion 432 may be formed in a cylindrical shape similar to the abutment portion 412 of the tool change arm 1 according to the first embodiment, or may be formed to protrude in a wall shape similar to the abutment portion 413 provided on the tool change arm 1A according to the second embodiment. The abutment portion 432 comes into line contact with the side peripheral surface 321b of the fixed portion 321 when the tool gripping portion 4A is moved in the rotational direction about the spindle central axis J1 (grip axis J3) to the position of the swivel portion 3 in the second step. Therefore, like the tool change arm 1, the tool gripping portion 4A of this tool change arm 1C can reliably position the tool gripping portion 4A.

[0045] Instead of the abutment portion 432 of the tool gripping portion 4A, the tool exchange arm 1C may be provided with an abutment portion that protrudes downward from the underside of the fixed portion 321 of the mounting plate portion 32 in the swivel portion 3, as in the tool exchange arm 1B of the third embodiment.

[0046] The following supplementary notes are further disclosed regarding the above-described embodiment and modified examples. (Supplementary Note 1) A tool change arm (1, 1A, 1B, 1C) in a tool changer that changes a tool (200) for a spindle (101) of a machine tool includes a base (2), a swivel (3) supported on the base (2) so as to be rotatable about a rotation axis (J2) parallel to a spindle central axis (J1) that is the rotation center of the spindle (101), a tool gripping unit (4, 4A) attached to the swivel (3) and capable of gripping the tool (200) in an orientation in which a tool central axis (J4) that is the rotation center of the tool (200) is parallel to the spindle central axis (J1), and either the tool gripping unit (4, 4A) or the swivel (3) is supported. abutting portions (412, 413, 323, 432) provided on either the swivel portion (3) or the tool gripping portion (4, 4A) and arranged to come into contact with the swivel portion (3) or the tool gripping portion (4, 4A) when the tool gripping portion (4, 4A) moves in a rotational direction about the tool central axis (J4) in a state where the spindle central axis (J1) and the tool central axis (J4) when the tool gripping portion (4, 4A) grips the tool (200) are aligned, and a fixing portion (321) that fixes the tool gripping portion (4, 4A) to the swivel portion (3) in a state where the abutting portions (412, 413, 323, 432) are in contact with the swivel portion (3) or the tool gripping portion (4, 4A).

[0047] (Supplementary Note 2) In the tool change arm (1, 1A, 1B, 1C) of Supplementary Note 1, the abutment portion (412, 413, 323, 432) is arranged to be in line contact with the swivel portion (3) or the tool gripping portion (4, 4A) along a direction parallel to the swivel axis (J2) of the swivel portion (3).

[0048] (Supplementary Note 3) In the tool change arm (1, 1A, 1B) of Supplementary Note 1 or 2, the tool gripping unit (4) has a support base (41) fixed to the swivel unit (3) at the fixing portion (321), and a rotating unit (42) that rotates relative to the support base (41) around a rotation axis (J5) perpendicular to the rotation axis (J2) of the swivel unit (3) to move the gripped tool (200) toward and away from the spindle (101).

[0049] (Supplementary Note 4) In the tool change arm (1C) of Supplementary Note 1 or 2, the tool gripping portion (4A) is configured to move the gripped tool (200) toward and away from the spindle (101) by pivoting about the pivot axis (J2) of the pivoting portion (3).

[0050] (Supplementary Note 5) A method for adjusting a tool change arm (1, 1A, 1B, 1C) for changing a tool (200) for a spindle (101) of a machine tool, the tool change arm (1, 1A, 1B, 1C) comprising: a base (2); a swivel (3) supported on the base (2) so as to be swivelable about a swivel axis (J2) parallel to a spindle central axis (J1) which is the rotation center of the spindle (101); and a tool (200) attached to the swivel (3) and capable of gripping the tool (200) in a position where a tool central axis (J4) which is the rotation center of the tool (200) is parallel to the spindle central axis (J1). The tool gripping method includes a tool gripping portion (4, 4A) and includes a first step of arranging the tool gripping portion (4, 4A) at a position where the spindle central axis (J1) coincides with the tool central axis (J4) when the tool gripping portion (4, 4A) grips the tool (200); a second step of moving the tool gripping portion (4, 4A) in a rotational direction about the spindle central axis (J1) to the position of the swivel portion (3) to adjust its attachment position relative to the swivel portion (3); and a third step of fixing the tool gripping portion (4, 4A) moved to the position of the swivel portion (3) and the swivel portion (3).

[0051] (Appendix 6) In the method for adjusting the tool change arm (1, 1A, 1B, 1C) of Appendix 5, in the first step, the tool (200) is attached to the spindle (101) and held by the tool holding portion (4, 4A), thereby positioning the tool holding portion (4, 4A) at a position where the spindle central axis (J1) and the tool central axis (J4) coincide with each other.

[0052] (Supplementary Note 7) In the method for adjusting the tool change arm (1, 1A, 1B, 1C) of Supplementary Note 5 or 6, abutment portions (412, 413, 323, 432) are provided on either the tool gripping portion (4, 4A) or the swivel portion (3), and in a second step, when the tool gripping portion (4, 4A) is moved in a rotational direction around the spindle central axis (J1) to the position of the swivel portion (3), the abutment portions (412, 413, 323, 432) are brought into contact with the swivel portion (3) or the tool gripping portion (4, 4A), and in a third step, the tool gripping portion (4, 4A) and the swivel portion (3) are fixed in a state in which the abutment portions (412, 413, 323, 432) are in contact with the swivel portion (3) or the tool gripping portion (4, 4A).

[0053] (Appendix 8) In the method for adjusting the tool change arm (1, 1A, 1B, 1C) of Appendix 7, the abutment portion (412, 413, 323, 432) is arranged to be in line contact with the swivel portion (3) or the tool gripping portion (4, 4A) along a direction parallel to the swivel axis (J2) of the swivel portion (3).

[0054] Although the present disclosure has been described in detail above, the present disclosure is not limited to the individual embodiments described above. Various additions, substitutions, modifications, partial deletions, etc. are possible in these embodiments without departing from the gist of the present disclosure or the spirit of the present disclosure derived from the content of the claims and their equivalents. These embodiments can also be implemented in combination. For example, in the above-described embodiments, the order of each operation and the order of each process are shown as examples and are not limited to these. The same applies when numerical values ​​or mathematical expressions are used in the description of the above-described embodiments.

[0055] 1, 1A, 1B, 1C Tool exchange arm 2 Base portion 3 Swivel portion 321 Fixed portion 4, 4A Tool gripping portion 41 Support base portion 412, 413, 323, 432 Abutment portion 42 Rotating portion 101 Spindle of machine tool 200 Tool J1 Spindle central axis J2 Swivel axis J4 Tool central axis J5 Rotation axis

Claims

1. A tool changing arm for changing a tool with respect to a spindle of a machine tool, comprising: a base portion; a swivel portion supported so as to be swivellable about a swivel axis parallel to a spindle center axis which is the rotation center of the spindle, with respect to the base portion; a tool gripping portion attached to the swivel portion and capable of gripping the tool in a posture in which a tool center axis which is the rotation center of the tool is parallel to the spindle center axis; a butting portion provided on either one of the tool gripping portion and the swivel portion, and arranged so as to contact the swivel portion or the tool gripping portion when the tool gripping portion moves in a rotational direction about the tool center axis in a state where the spindle center axis and the tool center axis when the tool gripping portion grips the tool coincide; and a fixing portion for fixing the tool gripping portion and the swivel portion in a state where the butting portion contacts the swivel portion or the tool gripping portion.

2. The tool changing arm according to claim 1, wherein the butting portion is arranged so as to be in line contact with the swivel portion or the tool gripping portion along a direction parallel to the swivel axis of the swivel portion.

3. The tool changing arm according to claim 1 or 2, wherein the tool gripping portion has: a support base portion fixed to the swivel portion in the fixing portion; and a rotating portion that rotates about a rotation axis orthogonal to the swivel axis of the swivel portion with respect to the support base portion, and thereby moves the tool to be gripped closer to and away from the spindle.

4. The tool changing arm according to claim 1 or 2, wherein the tool gripping portion is configured to move the tool to be gripped closer to and away from the spindle by rotating about the swivel axis of the swivel portion.

5. A method for adjusting a tool changing arm that changes a tool with respect to a spindle of a machine tool, the tool changing arm comprising: a base portion; a swivel portion supported by the base portion so as to be capable of swiveling about a swivel axis parallel to a spindle center axis that is the rotation center of the spindle; and a tool gripping portion attached to the swivel portion and capable of gripping the tool in a posture in which a tool center axis that is the rotation center of the tool is parallel to the spindle center axis, the method comprising: a first step of arranging the tool gripping portion at a position where the spindle center axis and the tool center axis coincide when the tool is gripped by the tool gripping portion; a second step of moving the tool gripping portion in a rotational direction about the spindle center axis to a position of the swivel portion to adjust an attachment position with respect to the swivel portion; and a third step of fixing the tool gripping portion that has been moved to the position of the swivel portion and the swivel portion.

6. The method for adjusting a tool changing arm according to claim 5, wherein in the first step, the tool gripping portion is arranged at a position where the spindle center axis and the tool center axis coincide by attaching the tool to the spindle and gripping the tool with the tool gripping portion.

7. A method for adjusting a tool changing arm according to claim 5 or 6, wherein a butting portion is provided on either the tool gripping portion or the swivel portion, and in the second step, when the tool gripping portion is moved in a rotational direction about the spindle center axis to the position of the swivel portion, the butting portion is brought into contact with the swivel portion or the tool gripping portion, and in the third step, the tool gripping portion and the swivel portion are fixed in a state where the butting portion is in contact with the swivel portion or the tool gripping portion.

8. The method for adjusting a tool changing arm according to claim 7, wherein the butting portion is arranged so as to be in line contact with the swivel portion or the tool gripping portion along a direction parallel to the swivel axis of the swivel portion.

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