Tool changer for machine tool

Abstract

This tool changer for a machine tool 10 comprises: a tool storage part 35 rotatably journaled to a tool magazine 30 and capable of storing a tool; and an operation means for causing a tool holding part 26 to rotate so that an apex 29d of a holding protrusion 29c is positioned above a recess projection straight line 201Y obtained by projecting a recess 201 of a tool 200 in a state where the tool 200 is stored in the tool storage part 35 in a direction along a rotation central axis J7 of the tool storage part 35 when the tool 200 is handed between the tool storage part 35 and the tool holding part 26 when viewed in the direction along the rotation central axis J7 of the tool storage part 35.

Description

Tool changer for machine tools

[0001] The present disclosure relates to a tool changer for a machine tool.

[0002] A known automatic tool changer for a machine tool includes a tool change arm unit that attaches and detaches tools between a tool magazine having a tool storage section capable of storing tools and a spindle that rotates with the tools attached (see, for example, Patent Document 1). In conventional automatic tool changers, the engagement portion of the tool is generally configured as a recess, and the portion of the tool change arm unit that grips the tool is provided with a holding protrusion that fits into the recess of the tool. The holding protrusion fits into this recess, allowing the tool gripping portion of the tool change arm unit to grip the tool.

[0003] Japanese Patent Application Laid-Open No. 2020-192678

[0004] However, the recess of the tool is generally arranged so that it is linear when projected in the direction of the rotation axis of the tool storage unit. Therefore, when the tool gripping unit or the tool storage unit is rotated to engage or disengage the recess of the tool with the holding protrusion of the tool gripping unit, misalignment occurs between the recess and the holding protrusion during the rotation. This puts a load on the holding protrusion, which can cause it to wear out prematurely.

[0005] The object of the present disclosure is to provide a tool changer for a machine tool that can reduce the load on the holding protrusion of the tool gripping portion when transferring a tool between the tool storage portion of a tool magazine and the tool gripping portion of a tool change arm unit.

[0006] The present disclosure relates to a tool change device for a machine tool including a tool magazine and a tool change arm unit, wherein the tool magazine includes a tool storage section rotatably supported relative to the tool magazine and capable of storing tools, and the tool change arm unit includes a swivel base, a swivel section rotatably supported relative to the swivel base, a tool gripping section rotatably supported relative to the swivel section, and a holding protrusion provided on the tool gripping section, the holding protrusion having an apex capable of engaging with a recessed section of a tool to grip the tool, and comprising operating means for rotating the tool gripping section so that, when viewed from a direction along the central axis of rotation of the tool storage section, when a tool is transferred between the tool storage section and the tool gripping section, the apex of the holding protrusion is positioned on a recessed section projection line obtained by projecting the recessed section of the tool stored in the tool storage section in a direction along the central axis of the tool storage section.

[0007] 5 is a perspective view showing a machine tool unit 1 of a first embodiment. FIG. 6 is a front view showing the machine tool unit 1 of the first embodiment. FIG. 7 is an enlarged perspective view showing the vicinity of the chuck portion 29. FIG. 8 is a side view showing a tool 200. FIG. 9 is a view showing the vicinity of the tool gripping portion 26 in a state where the apex 29d of the holding protrusion 29c is in a position where it starts to engage with the recessed portion 201 of the tool 200. FIG. 10 is a view showing the vicinity of the tool gripping portion 26 in a state where the apex 29d of the holding protrusion 29c is in a position midway through engagement with the recessed portion 201 of the tool 200. FIG. 11 is a view showing the vicinity of the tool gripping portion 26 in a state where the apex 29d of the holding protrusion 29c is engaged with the recessed portion 201 of the tool 200 and the chuck portion 29 holds the tool 200. FIG. 12 is a view explaining the relationship between the apex 29d and the recessed portion 201 in the state of FIG. 5. FIG. 13 is a view explaining the relationship between the apex 29d and the recessed portion 201 in the state of FIG. 14. FIG. 15 is a view explaining the relationship between the apex 29d and the recessed portion 201 in the state of FIG. 15. FIG. 16 is a view explaining the relationship between the apex 29d and the recessed portion 201 in the state of FIG. 16. FIG. 17 is a view explaining the shape of a cam surface 51a. FIG. 18 is a perspective view showing a machine tool unit 1B of a second embodiment. 1 is a front view showing a machine tool unit 1B of a second embodiment; FIG. 2 is a view showing the vicinity of the tool gripping section 26 in a state where the action piece 66 is in a position where it begins to contact the storage section roller 67; FIG. 3 is a view showing the vicinity of the tool gripping section 26 in a state where the action piece 66 is in the middle of pushing the storage section roller 67 to rotate the tool storage section 35 to the tool attachment / detachment position; FIG. 4 is a view showing the vicinity of the tool gripping section 26 in a state where the action piece 66 has pushed the storage section roller 67 to rotate the tool storage section 35 to the tool attachment / detachment position; FIG. 5 is a view showing the vicinity of the tool gripping section 26 in a state where the action piece 66 has completed rotating the tool storage section 35 to the tool attachment / detachment position by pushing the storage section roller 67; FIG. 6 is a view showing a state where the vertex 29d begins to engage with the recess 201 in the second embodiment; FIG. 7 is a view showing a state where the vertex 29d is in the middle of engaging with the recess 201 of the tool 200 in the second embodiment; FIG. 8 is a view showing a state where the vertex 29d is engaged with the recess 201 of the tool 200 and the chuck section 29 holds the tool 200 in the second embodiment; and

[0008] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the description of the second and subsequent embodiments, the same reference numerals will be used to designate components common to the first and second embodiments, and the description thereof will be omitted as appropriate.

[0009] First Embodiment FIG. 1 is a perspective view showing a machine tool unit 1 according to a first embodiment. FIG. 2 is a front view showing a machine tool unit 1 according to the first embodiment. Note that the following drawings, including FIG. 1, are schematic views, and the size and shape of each part are exaggerated or omitted as appropriate for ease of understanding. For ease of explanation, the drawings are provided with X, Y, and Z Cartesian coordinates, and the following description will use these coordinates to explain the orientation of each part. The X and Y axes are parallel to the horizontal direction, and the Z axis is parallel to the vertical direction. In addition, the description will be made with the -Y side as the front, the +Y side as the rear, the +Z side as the top, and the -Z side as the bottom.

[0010] The machine tool unit 1 includes a machine tool 10, a tool change arm unit 20, and a tool magazine 30. The tool change arm unit 20 and the tool magazine 30 form part of a tool change device of the machine tool 10.

[0011] The machine tool 10 includes a base portion 11 , a spindle head 12 , and a spindle 13 .

[0012] In this specification and claims, the base 11 refers to a member that does not move relative to the spindle center axis J1 of the spindle 13 among the members that make up the machine tool 10. Therefore, the base 11 is not limited to a single member, and may be a plurality of members. The machine tool 10 is installed by fixing a portion of the base 11 to the floor or the like of the installation location.

[0013] The spindle head 12 is fixed to the base portion 11 and includes a drive source, a drive mechanism, etc. for driving the spindle 13 to rotate.

[0014] The spindle 13 protrudes downward from the spindle head 12 and is rotated by a drive source (not shown). A tool 200 is detachably attached to the lower end of the spindle 13. The spindle 13 performs various types of machining on a workpiece (not shown) by rotating the tool. In the following description, the spindle central axis J1, which is the center of rotation of the spindle 13, is assumed to be disposed in the vertical direction (the direction along the Z axis in FIG. 1 ), but the direction of the spindle central axis J1 is not limited to this direction.

[0015] The tool change arm unit 20 cooperates with a tool magazine 30 (described later) to form an automatic tool changer (ATC) that automatically changes a held tool between the tool storage section 35 and the spindle 13. The tool change arm unit 20 includes a linear motion unit 21, a lifting shaft 22, a swivel base 23, a swivel shaft 24, a mounting plate section 25, a tool holding section 26, and a holding section cam mechanism 50.

[0016] The linear motion unit 21 is disposed in a region between the spindle 13 (spindle central axis J1) and the tool magazine 30 when viewed from the front (-Y side), and is fixed to the base portion 11 while being positioned with respect to the spindle central axis J1. The linear motion unit 21 is provided with an internal lift motor (not shown), and moves the tool gripping portion 26 up and down together with the swivel base 23 via the lift shaft 22.

[0017] The lift shaft 22 protrudes downward from the linear motion unit 21. A swivel base 23 is attached to the lower end of the lift shaft 22. The lift shaft 22 can be configured, for example, with a ball screw, in which case the swivel base 23 can be configured to be screwed onto the ball screw of the lift shaft 22. When the lift motor of the linear motion unit 21 rotates the lift shaft 22, the lift shaft 22 rotates and the swivel base 23 moves up and down along the Z-axis direction.

[0018] The swivel base 23 is configured in a substantially box shape and is provided so as to be movable up and down by the linear motion unit 21. The direction of the vertical movement of the swivel base 23 is parallel to the spindle central axis J1. A motor (not shown) is housed inside the swivel base 23.

[0019] The swivel shaft 24 extends vertically downward from the underside of the swivel base 23. The swivel shaft 24 is connected to the output shaft of a motor (not shown) housed in the swivel base 23. Driven by the motor of the swivel base 23, the swivel shaft 24 can rotate clockwise and counterclockwise relative to the swivel base 23 around a swivel center axis J2, which is the central axis of the swivel shaft 24. The swivel center axis J2 is disposed along the length of the swivel shaft 24 and parallel to the main spindle center axis J1.

[0020] The mounting plate 25 is attached to the lower end of the pivot shaft 24 by a bolt (not shown). The mounting plate 25 is capable of pivoting clockwise and counterclockwise around the pivot central axis J2 as the pivot shaft 24 pivots. The mounting plates 25 extend in opposite directions across the pivot shaft 24. Tool gripping portions 26, 26 are fixed to each mounting plate 25 via two support base portions 27, 27, which will be described later. Note that, although the mounting plate 25 is plate-shaped in this embodiment, the present invention is not limited thereto and may be a non-plate-shaped portion.

[0021] The tool gripping portions 26 are attached to the mounting plate portion 25. The tool gripping portions 26 are attached to respective fixed positions extending in opposite directions across the pivot shaft 24 of the mounting plate portion 25. Therefore, in this embodiment, as shown in Figures 1 and 2, two tool gripping portions 26 are attached to the fixed positions. The two tool gripping portions 26 have the same configuration except that they extend in opposite directions (180 degrees apart) from each other relative to the mounting plate portion 25. Therefore, the configuration of one tool gripping portion 26 will be described below.

[0022] The support base 27 is a portion that attaches the tool gripping portion 26 to the mounting plate 25, and is formed, for example, in a block shape. The mounting plate 25 and the support base 27 are both pivotally supported so as to be able to pivot clockwise and counterclockwise around the pivot center axis J2 as the pivot shaft 24 pivots.

[0023] The tool gripping unit 26 has an arm 28 and a chuck 29. The arm 28 extends from a portion attached to the support base 27 toward the chuck 29, bending midway. The arm 28 is attached to the support base 27 so as to be rotatable about a rotation axis J5 by driving a motor (not shown) provided on the support base 27. In this embodiment, the arm 28 is driven by a motor, but this is not limited to motor driving and other driving sources may also be used. For example, the arm 28 may be rotated in one direction by an elastic member such as a tension spring, or may be rotated by an air cylinder or the like. The rotation axis J5 is an axis perpendicular to the rotation axis J2 of the pivot shaft 24.

[0024] FIG. 3 is an enlarged perspective view of the chuck portion 29 and its vicinity. FIG. 4 is a side view of the tool 200. The chuck portion 29 is provided at the tip of the arm portion 28. As shown in FIG. 3, the chuck portion 29 has gripping arms 29a, 29a that are bifurcated into a U-shape from the tip of the arm portion 28. The inner sides of the gripping arms 29a, 29a are formed in an arc shape to fit the outer periphery of the tool 200 to be gripped. As shown in FIG. 3, a convex portion 29b extending in an arc shape is formed on the inner sides of the gripping arms 29a, 29a. As shown in FIG. 4, the convex portion 29b is formed to fit into a recess 201 formed in an annular shape on the outer periphery of the tool 200.

[0025] At the tips of the gripping arms 29 a, 29 a, holding protrusions 29 c, 29 c that fit into the recesses 201 of the tool 200 to hold the tool 200 are provided so as to face each other. The tip side of the holding protrusion 29 c is substantially spherical, with an apex 29 d at its center. This apex 29 d does not have to be sharp. When the tip of the holding protrusion 29 c is configured to be substantially spherical, as in this embodiment, the apex 29 d corresponds to the most distal end of the spherical shape, which is the center of the holding protrusion 29 c when viewed from a direction along the rotation center axis J7 of the tool storage unit 35.

[0026] The chuck portion 29 holds the tool 200 by fitting the convex portion 29b into the concave portion 201 of the tool 200 and fitting the holding protrusions 29c, 29c into the concave portion 201 of the tool 200. A tool gripping axis J3 of the tool gripping portion 26 when gripping the tool 200 coincides with a tool central axis J4 which is the center of rotation of the tool 200. The arm portion 28 rotates about a rotation central axis J5 to move the gripped tool 200 toward or away from the spindle 13 or the tool storage portion 35.

[0027] The tool magazine 30 is disposed to the left (-X side) of the pivot shaft 24 (central pivot axis J2) when viewed from the front (-Y side). The tool magazine 30 includes a magazine base 31, a magazine body 32, a turntable 33, a storage arm 34, and a tool storage section 35.

[0028] The magazine base 31 is connected to the base portion 11 of the machine tool 10. In this embodiment, the magazine base 31 is in a generally plate-like shape and protrudes from the magazine body 32 toward the base portion 11 side.

[0029] The magazine body 32 is configured as an integral part with the magazine base 31. Here, "integrated" does not necessarily mean that the parts are integrated as one unit, but also includes a configuration in which a plurality of parts are combined and integrated. In this embodiment, the magazine body 32 and the magazine base 31 are also configured as separate parts and are integrated using bolts (not shown). The magazine body 32 has a motor (not shown) inside it, which rotates and drives the turntable 33 (described later).

[0030] The turntable 33 is located to the side of the magazine body 32 and is attached to the magazine body 32 so as to be rotatable about a rotation center axis J6 by a motor of the magazine body 32. The rotation center axis J6 is an axis that is perpendicular to the main shaft center axis J1 and the turning center axis J2.

[0031] The multiple storage arms 34 are attached to the turntable 33 at radial intervals near the outer periphery of the turntable 33. In this embodiment, the storage arms 34 extend in a generally L-shape with a bend midway, but this shape can be modified as appropriate. The storage arms 34 have a motor (not shown) built in them, which rotates and drives the tool storage unit 35 (described below). Note that, although this embodiment shows an example in which the storage arms 34 are driven by a motor, the storage arms 34 may also be driven by other drive sources other than the motor.

[0032] The tool storage section 35 has a storage hole 35a at one end for storing the tool 200. The other end of the tool storage section 35 is rotatably attached to the tip of the storage arm 34. In this embodiment, the tool storage section 35 has a substantially cylindrical shape, but this shape can be modified as appropriate. The tool storage section 35 is provided at the tip of the storage arm 34 so as to be rotatable about a rotation center axis J7 by the motor of the storage arm 34. Note that, although the tool storage section 35 is driven by a motor in this embodiment, it is not limited to motor drive, and other drive sources may also be used. For example, the tool storage section 35 may be configured to rotate in one direction by an elastic member such as a tension spring, or may be configured to rotate by an air cylinder or the like. The direction in which the rotation center axis J7 extends changes with the rotation of the turntable 33.

[0033] A plurality of storage arms 34 and tool storage sections 35 are arranged near the outer periphery of the turntable 33. Different tools 200 are stored in these tool storage sections. In this embodiment, six sets of storage arms 34 and tool storage sections 35 are arranged radially at equal angular intervals. Note that in Figures 1 and 2, only the tool storage section 35 in the exchange position is shown with the tools 200 stored therein.

[0034] As shown in FIG. 1 , the rotation center axis J7 at the position where the tool 200 is exchanged is perpendicular to the spindle center axis J1 and the swivel center axis J2. The central axis of the storage hole 35a, which coincides with the tool center axis J4 when the tool 200 is stored in the storage hole 35a, is defined as the storage center axis J8. The storage center axis J8 of the tool storage unit 35 at the position where the tool 200 is exchanged is parallel to the spindle center axis J1 and the swivel center axis J2. Meanwhile, the storage center axis J8 of the tool storage unit 35 at the position where the tool 200 is not exchanged is perpendicular to the spindle center axis J1 and the swivel center axis J2 and parallel to the rotation center axis J6 of the turntable 33.

[0035] The gripper cam mechanism 50 includes a flat cam 51 and a gripper roller 52, and is an operating means for rotating the tool gripper 26.

[0036] The planar cam 51 is fixed to the base portion 11, and has a cam surface 51a of the planar cam on the right side surface (surface on the +X side).

[0037] The gripping roller 52 is rotatably attached to the tool gripping portion 26 , and its outer circumferential surface abuts against the cam surface 51 a of the flat cam 51 .

[0038] As described above, the swivel base 23 is moved in the vertical direction (along the Z-axis) by the linear motion unit 21. Therefore, the configuration from the swivel base 23 to the tool gripping portion 26, i.e., the swivel base 23, the swivel shaft 24, the mounting plate portion 25, the support base portion 27, and the tool gripping portion 26, move in the vertical direction (along the Z-axis). When the tool gripping portion 26 moves in the vertical direction (along the Z-axis), the position of the apex 29d of the holding protrusion 29c of the tool gripping portion 26 is regulated by the gripping portion roller 52 abutting against the cam surface 51a. Therefore, the position of the apex 29d changes according to the position of the gripping portion roller 52 abutting against the cam surface 51a.

[0039] In the machine tool unit 1 of this embodiment, the motors of the above-mentioned components are comprehensively controlled by a control unit (not shown) to operate in coordination with each other, and the tool 200 is automatically replaced. When replacing the tool 200, the gripper cam mechanism 50 reduces excessive load on the holding protrusion 29c when the tool 200 is attached to or removed from the tool storage section 35 of the tool magazine 30. The operation when replacing the tool 200 will be described below.

[0040] When attaching a tool to the spindle 13, first, the tool gripping unit 26 rotates, and the tool gripping unit 26 gripping the tool 200 is moved onto the spindle center axis J1 of the spindle 13. Next, the tool gripping unit 26 moves axially relative to the spindle 13, and the tool 200 is inserted into the spindle 13. A clamping mechanism (not shown) of the spindle 13 operates, and the tool 200 is gripped by the spindle 13. Next, the tool gripping unit 26 rotates, thereby releasing the tool 200. When removing the tool from the spindle 13, the above steps are performed in reverse order.

[0041] FIG. 5 is a view showing the vicinity of the tool gripping portion 26 in a state where the apex 29d of the holding protrusion 29c is in a position where it begins to engage with the recess 201 of the tool 200. FIG. 6 is a view showing the vicinity of the tool gripping portion 26 in a state where the apex 29d of the holding protrusion 29c is in a position where it is midway through engagement with the recess 201 of the tool 200. FIG. 7 is a view showing the vicinity of the tool gripping portion 26 in a state where the apex 29d of the holding protrusion 29c is engaged with the recess 201 of the tool 200 and the chuck portion 29 holds the tool 200. FIG. 8 is a view explaining the relationship between the apex 29d and the recess 201 in the state shown in FIG. 5. FIG. 9 is a view explaining the relationship between the apex 29d and the recess 201 in the state shown in FIG. 6. FIG. 10 is a view explaining the relationship between the apex 29d and the recess 201 in the state shown in FIG. 7. In FIGS. 5 to 7, only the outer contour of the tool 200 is shown, and the shape of a portion of the chuck portion 29 that overlaps the tool 200 is shown by a solid line for ease of understanding. 8 to 10, for ease of understanding, only a portion of the shape of the chuck portion 29 around the apex 29d and the holding protrusion 29c is shown, and other shapes are omitted. The operation of removing the tool 200 from the tool storage section 35 of the tool magazine 30 will be described using these Figures 5 to 10.

[0042] 8 to 10 show the tool 200 as viewed from a direction along the rotation center axis J7 of the tool storage unit 35 from which the tool 200 is to be removed (i.e., a direction along the Y axis). In addition, in FIGS. 8 to 10, a recess projection line 201Y, which is a projection of the recess 201 of the tool 200 in a state in which the tool 200 is stored in the tool storage unit 35, in a direction along the rotation center axis J7 of the tool storage unit 35, is shown by a dashed line. Furthermore, a convex portion projection line 29Y, which is a projection of the convex portion 29b of the chuck unit 29 in the same manner as the recess projection line 201Y, is shown by a dashed-dotted line. Note that the convex portion projection line 29Y is shown extended for ease of viewing.

[0043] When removing the tool 200 from the tool storage section 35 of the tool magazine 30, the tool gripping section 26 is moved to the central axis (storage central axis J8) of the tool when the tool storage section 35 stores the tool 200. At this time, the linear motion unit 21 moves the tool gripping section 26 downward (to the -Z side) together with the mounting plate section 25, the support base section 27, etc.

[0044] 5 and 8, when the apex 29d reaches a position where it begins to engage with the recess 201, the gripper roller 52 reaches the cam surface 51a, moving the position of the apex 29d to the position shown in Fig. 8. At this time, when viewed from a direction along the rotation center axis J7 of the tool storage unit 35, i.e., in Fig. 8, the apex 29d is positioned on the recess projection line 201Y. Therefore, the holding protrusion 29c is introduced into the recess 201 without applying a large load to the holding protrusion 29c.

[0045] 6 and 9, when the operation progresses and the apex 29d approaches the center of the tool 200, the gripper roller 52 moves the position of the apex 29d to the position shown in Fig. 9 in accordance with the cam surface 51a. Even in this case, when viewed from the direction along the rotation center axis J7 of the tool storage unit 35, i.e., in Fig. 9, the apex 29d is positioned on the recess projection line 201Y. Therefore, the holding protrusion 29c can continue to move along the recess 201 without applying a large load to the holding protrusion 29c.

[0046] As the operation continues, as shown in Figures 7 and 10, the apex 29d advances to the back of the tool 200, and the tool 200 is completely held by the chuck 29. In this state, the gripper roller 52 moves the position of the apex 29d to the position shown in Figure 10 in accordance with the cam surface 51a. Even in this case, when viewed from the direction along the rotation center axis J7 of the tool storage unit 35, i.e., in Figure 10, the apex 29d is positioned on the recess projection line 201Y. Furthermore, in this state, the recess projection line 201Y and the protrusion projection line 29Y overlap.

[0047] 8 to 10, the vertex 29d is always positioned on the recess projection straight line 201Y from just before reaching the recess 201 until the tool 200 is completely held by the chuck portion 29. In other words, when viewed from a direction along the rotation center axis J7 of the tool storage portion 35, the vertex 29d is always positioned on the recess projection straight line 201Y in the vicinity of the tool 200. Therefore, the holding protrusion 29c can hold the tool 200 without applying a large load to the holding protrusion 29c.

[0048] After the chuck portion 29 completely holds the tool 200, a clamping mechanism (not shown) of the tool storage portion 35 releases the clamp on the tool 200, and the tool gripping portion 26 moves downward (towards the -Z side) to remove the tool from the tool storage portion 35.

[0049] When attaching the tool 200 to the tool storage section 35 of the tool magazine 30, the tool gripping section 26 holding the tool 200 is moved to the storage center axis J8 of the target tool storage section 35, and the tool 200 is inserted into the storage hole 35a, and a clamping mechanism (not shown) clamps the tool 200. The chuck section 29 is then released from the tool 200 by the reverse process of the above-described removal of the tool 200. Even in this case, when viewed from the direction along the rotation center axis J7 of the tool storage section 35, the vertex 29d is always positioned on the recess projection line 201Y in the vicinity of the tool 200. Therefore, the holding protrusion 29c can release the tool 200 without applying a large load to the holding protrusion 29c.

[0050] To specifically realize the above operation, the shape of the cam surface 51a is important. FIG. 11 is a diagram illustrating the shape of the cam surface 51a. The shape of this cam surface 51a is the envelope of the set of outer circumferential circles 52a of the gripper roller 52 at the rotation angle of the tool gripper 26 at which the apex 29d of the holding protrusion 29c is positioned on the recess projection line 201Y. By determining the shape of the cam surface 51a using the envelope, an appropriate cam surface 51a can be easily created. Note that this shape of the cam surface 51a is required only within a specific range within the operating range of the pivoting unit (corresponding to the mounting plate 25 and the support base 27) and the tool gripper 26 along the pivot axis 24 (direction along the Z axis). Specifically, this specific range refers to a range in which the holding protrusion 29c and the recess 201 may come into contact with each other. It is desirable that the range be a range in which the apex 29d overlaps with the tool 200 when viewed from the direction along the rotation center axis J7 of the tool storage unit 35. Furthermore, when viewed from the direction along the rotation center axis J7 of the tool storage section 35, it is more desirable to provide a small margin in the range where the vertex 29d overlaps with the tool 200. The value of this margin can be, for example, 5 mm or more.

[0051] Second Embodiment Fig. 12 is a perspective view showing a machine tool unit 1B of a second embodiment. Fig. 13 is a front view showing a machine tool unit 1B of the second embodiment. The machine tool unit 1B of the second embodiment differs from the first embodiment in that it further includes a storage section cam mechanism 60.

[0052] The storage section cam mechanism 60 has a storage section planar cam 61, a first link 62, a driven roller 63, a second link 64, a linear motion member 65, an action piece 66, and a storage section roller 67. The storage section cam mechanism 60 operates as a tool storage section rotation interlocking mechanism that rotates the tool storage section 35 in conjunction with the operation of the tool change arm unit 20.

[0053] The storage section flat cam 61 is fixed to the swivel base 23, and has a cam surface 61a of the flat cam on its left side (the surface on the -X side). The storage section flat cam 61 moves up and down (along the Z-axis direction) together with the up and down movement of the swivel base 23.

[0054] The first link 62 is rotatably attached to the base portion 11. The first link 62 has a driven roller 63 rotatably attached to one end thereof, and a second link 64 rotatably attached to the other end thereof.

[0055] The driven roller 63 is rotatably attached to one end of the first link 62. The driven roller 63 abuts against the cam surface 61 a of the storage section flat cam 61. Therefore, the abutment position of the driven roller 63 with the cam surface 61 a changes as the storage section flat cam 61 moves up and down (in the direction along the Z axis), causing the driven roller 63 to rotate the first link 62.

[0056] One end of the second link 64 is rotatably attached to the other end of the first link 62, and the other end of the second link 64 is attached to the upper end of the linear motion member 65. In other words, the second link 64 connects the other end of the first link 62 to the upper end of the linear motion member 65. The second link 64 moves in conjunction with the rotation of the first link 62, moving the linear motion member 65 in the vertical direction (direction along the Z axis).

[0057] The linear motion member 65 is attached to a guide portion 11a provided on the base portion 11 so as to be movable in the vertical direction (direction along the Z axis).

[0058] The action piece 66 is located at the lower end (the end on the −Z side) of the linear motion member 65 and protrudes to the left (−X side) from the linear motion member 65 to a position where it can abut against the storage section roller 67.

[0059] The storage section roller 67 is attached to the end of the tool storage section 35 opposite to the side where the storage hole 35a is open. The storage section roller 67 is able to come into contact with the action piece 66. When the action piece 66 comes into contact with the storage section roller 67, the position of the tool storage section 35 in the rotational direction is restricted, and the tool storage section 35 rotates.

[0060] As described above, in the machine tool unit 1B of the second embodiment, the storage section cam mechanism 60 rotates the tool storage section 35 in conjunction with the up and down movement of the tool gripping section 26.

[0061] FIG. 14 is a view showing the vicinity of the tool gripping unit 26 when the action piece 66 is in a position where it begins to contact the storage roller 67. FIG. 15 is a view showing the vicinity of the tool gripping unit 26 when the action piece 66 is in the middle of pushing the storage roller 67 to rotate the tool storage unit 35 to the tool 200 attachment / detachment position. FIG. 16 is a view showing the vicinity of the tool gripping unit 26 when the action piece 66 has pushed the storage roller 67 to rotate the tool storage unit 35 to the tool 200 attachment / detachment position. As shown in FIGS. 14 and 15 , the tool storage unit 35 can rotate between the storage position shown in FIG. 14 and the tool 200 attachment / detachment position shown in FIG. 16 . This rotation of the tool storage unit 35 is performed in conjunction with the vertical movement of the tool gripping unit 26 (in the direction along the Z axis).

[0062] In the second embodiment, as described above, the tool storage unit 35 rotates, and during this rotation, the holding protrusion 29c engages with the recess 201 of the tool 200. Therefore, the cam shape of the cam surface 51a of the planar cam 51 in the second embodiment is a cam shape that takes into account the rotational position of the tool 200, and the cam profile is different from that of the first embodiment. As in the first embodiment, the cam shape of the cam surface 51a of the planar cam 51 in the second embodiment is formed by the envelope of a set of outer circumferential circles 52a of the gripper rollers 52 at the rotation angle of the tool gripper 26 that positions the apex 29d of the holding protrusion 29c on the recess projection straight line 201Y.

[0063] Therefore, in the second embodiment as well, the apex 29d of the holding protrusion 29c is always positioned on the recess projection straight line 201Y during the engagement operation with the recess 201.

[0064] FIG. 17 is a diagram showing a state in which the apex 29d begins to engage with the recess 201 in the second embodiment. FIG. 18 is a diagram showing a state in which the apex 29d is in the middle of engaging with the recess 201 of the tool 200 in the second embodiment. FIG. 19 is a diagram showing a state in which the apex 29d engages with the recess 201 of the tool 200 and the chuck portion 29 holds the tool 200 in the second embodiment. FIGS. 17 to 19 are similar to FIGS. 5 to 7 of the first embodiment. Also, in FIGS. 17 to 19, similar to FIGS. 5 to 7 of the first embodiment, a recess projection line 201Y, which is a projection of the recess 201 of the tool 200 in a state in which the tool 200 is stored in the tool storage portion 35, in a direction along the rotation center axis J7 of the tool storage portion 35, is shown by a dashed line. Also, similar to FIGS. 5 to 7 of the first embodiment, a convex portion projection line 29Y, which is a projection of the convex portion 29b of the chuck portion 29 in the same manner as the recess projection line 201Y, is shown by a dashed line.

[0065] 17 to 19 , in the machine tool unit 1B of the second embodiment, similarly to the machine tool unit 1 of the first embodiment, when viewed from a direction along the rotation central axis J7 of the tool storage section 35, the vertex 29d is always positioned on the recess projection line 201Y in the vicinity of the tool 200. Therefore, the holding protrusion 29c can attach and detach the tool 200 without applying a large load to the holding protrusion 29c.

[0066] Third Embodiment Figure 20 is a front view showing a machine tool unit 1C of a third embodiment. The machine tool unit 1C of the third embodiment is similar to the first embodiment except that it does not include a gripper cam mechanism 50. The machine tool unit 1C of the third embodiment does not use a planar cam as in the first embodiment, and controls the position of the apex 29d of the holding protrusion 29c to move along a path similar to that of the first embodiment. Specifically, a control unit (not shown) controls the vertical movement (direction along the Z axis) of the tool gripper 26 by the linear motion unit 21. In addition, a control unit (not shown) controls the rotation of the tool gripper 26 by driving a motor (not shown) provided on the support base 27. The vertical movement and rotation of the tool gripper 26 are controlled in an integrated manner.

[0067] As a result, in the machine tool unit 1C of the third embodiment, similarly to the machine tool unit 1 of the first embodiment, when viewed from a direction along the rotation central axis J7 of the tool storage section 35, the vertex 29d is always positioned on the recess projection line 201Y in the vicinity of the tool 200. Therefore, the holding protrusion 29c can perform the operation of attaching and detaching the tool 200 without applying a large load to the holding protrusion 29c.

[0068] In the third embodiment, as in the second embodiment, the tool 200 may be attached or detached during the rotation of the tool storage unit 35. In this case, a control unit (not shown) not only controls the vertical movement and rotation of the tool gripping unit 26 but also the rotation of the tool storage unit 35. As a result, as in the second embodiment, during the rotation of the tool storage unit 35, the vertex 29d is always positioned on the recess projection line 201Y in the vicinity of the tool 200 when viewed from the direction along the rotation center axis J7 of the tool storage unit 35. Therefore, the holding protrusion 29c can attach or detach the tool 200 without applying a large load to the holding protrusion 29c.

[0069] According to at least one of the embodiments described above, the load on the holding protrusion of the tool gripping portion can be reduced when a tool is transferred between the tool storage portion of the tool magazine and the tool gripping portion of the tool change arm unit.

[0070] Although the present disclosure has been described in detail, 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.

[0071] The following supplementary notes are further disclosed regarding the above-described embodiment and modified examples. (Supplementary Note 1) A tool changer (20, 30) of a machine tool (10) is a tool changer (20, 30) of a machine tool (10) that includes a tool magazine (30) and a tool change arm unit (20), wherein the tool magazine (30) includes a tool storage section (35) that is pivotally supported on the tool magazine (30) so as to be rotatable relative to the tool magazine (30) and that can store a tool (200), and the tool change arm unit (20) includes a swivel base (23), a swivel section (25, 27) that is pivotally supported on the swivel base (23), a tool gripping section (26) that is pivotally supported on the swivel section (25, 27) so as to be rotatable relative to the tool gripping section (26), and a recess ( and a holding protrusion (29c) having an apex (29d) that can grip the tool (200) by fitting into a recess (201) of the tool storage section (35). When viewed from a direction along the rotation center axis (J7) of the tool storage section (35), when the tool (200) is transferred between the tool storage section (35) and the tool gripping section (26), the apex (29d) of the holding protrusion (29c) is positioned on a recess projection line obtained by projecting the recess (201) of the tool (200) in a state in which the tool (200) is stored in the tool storage section (35) in a direction along the rotation center axis (J7) of the tool storage section (35).

[0072] (Supplementary Note 2) A tool changer (20, 30) for a machine tool (10) including a tool magazine (30) and a tool change arm unit (20), wherein the tool magazine (30) includes a tool storage section (35) that is pivotally supported relative to the tool magazine (30) and that can store a tool (200), and the tool change arm unit (20) includes a swivel base (23) and a tool holder (35) that is pivotally supported relative to the swivel base (23). a tool gripping portion (26) that is pivotally supported relative to the pivoting portions (25, 27) and has a roller (52); a holding protrusion (29c) that is provided on the tool gripping portion (26) and has an apex (29d) that can grip the tool (200) by fitting into a recess (201) of the tool (200); and a holding protrusion (29c) that is provided on the tool gripping portion (26) and has an apex (29d) that can grip the tool (200) by fitting into a recess (201) of the tool (200). and a flat cam (51) having a cam surface (51 a) at a position where the roller (52) abuts when the apex (29 d) of the holding protrusion (29 c) is present within a specific range within the operating range of the apex (29 d) of the holding protrusion (29 c), and the flat cam (51) has a cam surface (51 a) at a position where the roller (52) abuts when the apex (29 d) of the holding protrusion (29 c) is present within a specific range within the operating range of the apex (29 d) of the holding protrusion (29 c), and This defines the rotation angle of the tool gripping portion (26), and when viewed from a direction along the rotation center axis (J7) of the tool storage portion (35), the apex (29d) of the holding protrusion (29c) is positioned on a recess projection line (201Y) obtained by projecting the recess (201) of the tool (200) in a state in which the tool (200) is stored in the tool storage portion (35) in a direction along the rotation center axis (J7) of the tool storage portion (35).

[0073] (Supplementary Note 3) The tool changer (20, 30) of the machine tool (10) described in Supplementary Note 2 is provided with a tool storage unit rotation interlocking mechanism (60) that rotates the tool storage unit (35) in conjunction with the operation of the tool change arm unit (20).

[0074] (Supplementary Note 4) In the tool changer (20, 30) of the machine tool (10) described in Supplementary Note 2 or Supplementary Note 3, the cam surface (51 a) is made up of an envelope of a set of outer circumferential circles (52 a) of the rollers (52) at a rotation angle of the tool gripping portion (26) that positions the apex (29 d) of the holding protrusion (29 c) on the recess projection straight line (201Y) within a specific range within an operating range of the swivel portion (25, 27) and the tool gripping portion (26) in a direction along the pivot axis (24).

[0075] DESCRIPTION OF SYMBOLS 1, 1B, 1C Machine tool unit 10 Machine tool 11 Base portion 11a Guide portion 12 Spindle head 13 Spindle 20 Tool change arm unit 21 Linear motion unit 22 Lifting axis 23 Swivel base 24 Swivel axis 25 Mounting plate portion 26 Tool gripping portion 27 Support base portion 28 Arm portion 29 Chuck portion 29Y Projected straight line of convex portion 29a Grip arm portion 29b Convex portion 29c Holding protrusion 29d Vertex 30 Tool magazine 31 Magazine base 32 Magazine body 33 Turntable 34 Storage arm 35 Tool storage portion 35a Storage hole 50 Grip portion cam mechanism 51 Plane cam 51a Cam surface 52 Grip portion roller 52a Outer periphery circle 60 Storage portion cam mechanism 61 Storage section flat cam 61a Cam surface 62 First link 63 Follower roller 64 Second link 65 Linearly moving member 66 Action piece 67 Storage section roller 200 Tool 201 Recess 201Y Recess projection line

Claims

1. A tool changer for a machine tool comprising a tool magazine and a tool change arm unit, wherein the tool magazine comprises a tool storage section rotatably supported relative to the tool magazine and capable of storing tools, and the tool change arm unit comprises a swivel base, a swivel section rotatably supported relative to the swivel base, a tool gripping section rotatably supported relative to the swivel section, and a holding protrusion provided on the tool gripping section, the holding protrusion having an apex capable of engaging with a recessed section of a tool to grip the tool, and wherein the tool changer for a machine tool comprises operating means for rotating the tool gripping section so that, when viewed from a direction along the central axis of rotation of the tool storage section, when a tool is transferred between the tool storage section and the tool gripping section, the apex of the holding protrusion is positioned on a recessed section projection line obtained by projecting the recessed section of the tool stored in the tool storage section in a direction along the central axis of rotation of the tool storage section.

2. A tool changer for a machine tool comprising a tool magazine and a tool change arm unit, wherein the tool magazine comprises a tool storage section rotatably supported on the tool magazine and capable of storing tools, and the tool change arm unit comprises: a swivel base; a swivel section rotatably supported on the swivel base; a tool gripping section rotatably supported on the swivel section and having a roller; a holding protrusion provided on the tool gripping section and having an apex capable of gripping a tool by fitting into a recess of a tool; a linear motion unit that moves the swivel section and the tool gripping section in a direction along the pivot axis of the swivel section; and a flat cam having a cam surface at a position where the roller abuts when the apex of the holding protrusion is within a specific range within the operating range of the apex of the holding protrusion, The planar cam defines the rotation angle of the tool gripping unit by the roller abutting against the cam surface, and when viewed from a direction along the central axis of rotation of the tool storage unit, the apex of the holding protrusion is positioned on a recess projection line obtained by projecting the recess of the tool when the tool is stored in the tool storage unit in a direction along the central axis of rotation of the tool storage unit. This is a tool changer for a machine tool.

3. A tool changer for a machine tool according to claim 2, characterized in that it is provided with a tool storage unit rotation interlocking mechanism that rotates the tool storage unit in conjunction with the operation of the tool change arm unit.

4. A tool changer for a machine tool according to claim 2 or 3, wherein the cam surface is made up of the envelope of a set of outer circumferential circles of the rollers at a rotation angle of the tool gripping part that positions the apex of the holding protrusion on the projection line of the recess within a specific range within the operating range in the direction along the rotation axis of the swivel part and the tool gripping part.

Images