Tool changer and machine tool

Abstract

An automatic tool changer capable of accurately detecting the locked state of a tool held by a first gripping portion and a second gripping portion is provided. [Solution] The automatic tool changer includes a tool changer 21. The tool changer 21 includes a first gripper 31A and a second gripper 31B, a first lock mechanism 41A that operates between a locked state and a released state in association with the sliding movement of a first lock pin 42A, a second lock mechanism 41B that operates between a locked state and a released state in association with the sliding movement of a second lock pin 42B, and a pin coupling unit 61 that couples the first lock pin 42A and the second lock pin 42B to each other and slides along the axial direction of a predetermined axis 101 when the first lock mechanism 41A and the second lock mechanism 41B operate. The automatic tool changer further includes a detector 71 that can detect the position of the pin coupling unit 61 in the axial direction of the predetermined axis 101.

Description

[Technical field]

[0001] The present invention relates to an automatic tool changer. [Background technology]

[0002] For example, JP 2020-124762 A (Patent Document 1) discloses an automatic tool changer device including a first changer arm having a first gripping portion capable of holding a tool, and a second changer arm having a second gripping portion capable of holding a tool. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-124762 A Summary of the Invention [Problem to be solved by the invention]

[0004] As disclosed in the above-mentioned Patent Document 1, an automatic tool changer (ATC: Auto Tool Changer) is known that has a first gripping part and a second gripping part, each capable of gripping a tool, and that can simultaneously exchange a tool placed in a tool standby position with a tool held by a tool spindle or the like.

[0005] In such a so-called double-arm type automatic tool changer, it is necessary to accurately detect the locked state of the tool held by the first gripping portion and the second gripping portion in order to prevent the tool from falling off during tool change.

[0006] An object of the present invention is to provide an automatic tool changer capable of accurately detecting the locked state of a tool held by a first gripping portion and a second gripping portion. [Means for solving the problem]

[0007] An automatic tool changer according to the present invention includes a tool changer that changes tools by sliding in the axial direction of a predetermined axis and rotating about the predetermined axis. The tool changer includes a first gripping portion and a second gripping portion that are provided at a distance from each other in the circumferential direction of the predetermined axis and each of which can grip a tool, a first locking mechanism that includes a first locking pin extending in the axial direction of the predetermined axis and operates between a locked state in which the tool gripped by the first gripping portion is held and a released state in which the tool gripped by the first gripping portion is released in association with the sliding movement of the first locking pin along the axial direction of the predetermined axis, a second locking mechanism that includes a second locking pin extending in the axial direction of the predetermined axis and operates between a locked state in which the tool gripped by the second gripping portion is held and a released state in which the tool gripped by the second gripping portion is released in association with the sliding movement of the second locking pin along the axial direction of the predetermined axis, and a pin coupling unit that couples the first locking pin and the second locking pin to each other and slides along the axial direction of the predetermined axis when the first locking mechanism and the second locking mechanism are operated. The automatic tool changer further includes a detection unit capable of detecting the position of the pin connecting unit in the axial direction of the predetermined axis. Effect of the Invention

[0008] According to the present invention, it is possible to provide an automatic tool changer capable of accurately detecting the locked state of the tools held by the first gripping portion and the second gripping portion. [Brief description of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view illustrating a schematic diagram of an automatic tool changer (initial state) according to an embodiment of the present invention. [Diagram 2] 1 is a cross-sectional view illustrating a schematic diagram of an automatic tool changer (in a released state) according to an embodiment of the present invention. [Diagram 3] 1 is a cross-sectional view illustrating a schematic diagram of an automatic tool changer (in a locked state) according to an embodiment of the present invention. [Figure 4] 3 is a perspective view showing a tool exchange unit in the automatic tool exchange device in FIG. 2. [Diagram 5]5 is a cross-sectional view showing a schematic diagram of a drive mechanism of the tool exchange unit shown in FIG. 4. [Figure 6] FIG. 4 is a cross-sectional view showing the automatic tool changer during tool change. [Figure 7] FIG. 4 is another cross-sectional view showing the automatic tool changer during tool change. [Figure 8] FIG. 11 is yet another cross-sectional view showing the automatic tool changer during tool change. [Figure 9] FIG. 2 is a front view showing the automatic tool changer during tool change. [Figure 10] FIG. 4 is another front view showing the automatic tool changer during tool change. [Figure 11] FIG. 11 is yet another front view showing the automatic tool changer during tool change. [Figure 12] 4 is a flowchart showing steps of tool changing by the automatic tool changer. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described with reference to the accompanying drawings, in which the same or corresponding components are designated by the same reference numerals.

[0011] Fig. 1 is a cross-sectional view showing an automatic tool changer (initial state) according to an embodiment of the present invention. Fig. 2 is a cross-sectional view showing an automatic tool changer (released state) according to an embodiment of the present invention. Fig. 3 is a cross-sectional view showing an automatic tool changer (locked state) according to an embodiment of the present invention. Fig. 4 is a perspective view showing a tool changer in the automatic tool changer in Fig. 2.

[0012] Fig. 1 shows a cross-sectional shape of the automatic tool changer 100 shown in Fig. 9, which will be described later, when cut along a vertical plane. Fig. 2 and Fig. 3 show a cross-sectional shape of the automatic tool changer 100 shown in Fig. 10, which will be described later, when cut along a horizontal plane.

[0013] 1 to 4, an automatic tool changer 100 in this embodiment is provided in a machine tool. The machine tool may be a machining center, a multi-tasking machine having a turning function using a fixed tool and a milling function using a rotating tool, or an AM / SM hybrid machine capable of additive manufacturing and subtractive manufacturing of a workpiece.

[0014] The automatic tool changer 100 changes a tool used for machining a workpiece in a machining area of ​​a machine tool. In this embodiment, as an example, a case will be described in which the automatic tool changer 100 changes a tool attached to a tool spindle of a horizontal machining center.

[0015] The automatic tool changer 100 has a tool changer 21. The tool changer 21 changes tools by sliding in the axial direction of a predetermined axis 101 and rotating about the predetermined axis 101. In other words, the tool changer 21 is a part that slides in the axial direction of the predetermined axis 101 and rotates about the predetermined axis 101 together with a tool to be changed when the automatic tool changer 100 changes tools.

[0016] The predetermined axis 101 is an imaginary straight line that extends in a horizontal direction parallel to the rotation axis of the tool spindle.

[0017] The tool exchange unit 21 has a first gripping portion 31A and a second gripping portion 31B. The first gripping portion 31A and the second gripping portion 31B have the same structure.

[0018] As shown in Fig. 4, each of the gripping portions 31 of the first gripping portion 31A and the second gripping portion 31B can grip a tool. The gripping portion 31 has a half-ring shape capable of receiving a shank portion of a tool. The gripping portion 31 has a claw portion 31p. The claw portion 31p can swing about a swing axis 106 parallel to the predetermined axis 101. The claw portion 31p is provided so as to be able to come into contact with the shank portion of the tool gripped by the gripping portion 31.

[0019] The tool exchange unit 21 further has an arm unit 32. The arm unit 32 extends in an arm shape on both sides from the specified axis 101 toward the radially outward direction. The first grip unit 31A and the second grip unit 31B are provided at one end and the other end of the arm unit 32 in the radial direction of the specified axis 101, respectively. The first grip unit 31A and the second grip unit 31B are provided separately in the circumferential direction of the specified axis 101. The first grip unit 31A and the second grip unit 31B are provided at angular positions offset by 180° around the specified axis 101.

[0020] 4, in this specification, for convenience of explaining the structure of the automatic tool changer 100, one side and the other side along the axial direction of the predetermined axis 101 are referred to as the "proximal side" and the "distal side", respectively. The direction from the proximal side to the distal side in the axial direction of the predetermined axis 101 corresponds to the direction in which the tool is removed from the tool spindle or the tool pot, and the direction from the distal side to the proximal side in the axial direction of the predetermined axis 101 corresponds to the direction in which the tool is inserted into the tool spindle or the tool pot. With the gripper 31 as a reference, the shank of the tool extends to the proximal side in the axial direction of the predetermined axis 101, and the blade of the tool extends to the distal side in the axial direction of the predetermined axis 101.

[0021] The tool exchange unit 21 further includes a first locking mechanism 41A and a second locking mechanism 41B. The first locking mechanism 41A and the second locking mechanism 41B have the same structure.

[0022] The first lock mechanism 41A has a first lock pin 42A. The second lock mechanism 41B has a second lock pin 42B. Each of the lock pins 42 of the first lock pin 42A and the second lock pin 42B extends in the axial direction of the specified axis 101. The lock pin 42 has a pin shape extending in the axial direction of the specified axis 101.

[0023] The first locking mechanism 41A operates between a locked state in which the tool held by the first gripping portion 31A is held and a released state in which the tool held by the first gripping portion 31A is released, in accordance with the sliding movement of the first locking pin 42A along the axial direction of the predetermined axis 101. The second locking mechanism 41B operates between a locked state in which the tool held by the second gripping portion 31B is held and a released state in which the tool held by the second gripping portion 31B is released, in accordance with the sliding movement of the second locking pin 42B along the axial direction of the predetermined axis 101.

[0024] More specifically, the first lock pin 42A and the second lock pin 42B are provided at a distance in the circumferential direction of the specified axis 101. The first lock pin 42A and the second lock pin 42B are provided at angular positions offset by 180° around the specified axis 101. The first lock pin 42A is provided at a distance from the first gripping portion 31A on the radially inward side of the specified axis 101. The second lock pin 42B is provided at a distance from the second gripping portion 31B on the radially inward side of the specified axis 101.

[0025] The lock pin 42 is provided with a wedge portion 43. The wedge portion 43 has a groove shape recessed from the outer circumferential surface of the lock pin 42 facing radially outward of the specified axis 101. The wedge portion 43 is provided in a tapered shape so that the distance from the specified axis 101 to the groove bottom surface formed by the wedge portion 43 changes along the axial direction of the specified axis 101. The distance from the specified axis 101 to the groove bottom surface formed by the wedge portion 43 increases from the proximal side to the distal side in the axial direction of the specified axis 101.

[0026] Each of the locking mechanisms 41, the first locking mechanism 41A and the second locking mechanism 41B, further includes a spring member 46 and a locking rod 44.

[0027] The spring member 46 is provided on the lock pin 42. The spring member 46 is formed, for example, of a coil spring extending spirally in the axial direction of the specified axis 101. The spring member 46 applies an elastic force to the lock pin 42 in the axial direction of the specified axis 101. The spring member 46 applies an elastic force to the lock pin 42 in the direction from the distal side to the proximal side in the axial direction of the specified axis 101.

[0028] The lock rod 44 is provided between the grip portion 31 (claw portion 31p) and the lock pin 42. The lock rod 44 extends axially between the claw portion 31p and the lock pin 42. The lock rod 44 is guided by a guide member (not shown) to be slidable along the axial direction in which the lock rod 44 extends.

[0029] One end of the lock rod 44 is disposed relatively radially inward of the specified axis 101, and the other end of the lock rod 44 is disposed relatively radially outward of the specified axis 101. One end of the lock rod 44 abuts against the wedge portion 43. The lock rod 44 has a tapered portion 45. The tapered portion 45 is provided at one end of the lock rod 44. The tapered portion 45 forms a tapered surface that corresponds to the groove bottom surface formed by the wedge portion 43. The tapered portion 45 is in surface contact with the groove bottom surface formed by the wedge portion 43. The other end of the lock rod 44 is connected to the grip portion 31 (claw portion 31p).

[0030] 2, when the lock pin 42 is located on the distal side, the lock rod 44 is disposed at a stroke end on the radially inner side of the predetermined axis 101. The claw portion 31p is positioned away from the shank portion of the tool. Each of the first locking mechanism 41A and the second locking mechanism 41B is in a release state in which the tool gripped by the gripping portion 31 is released.

[0031] 3, when the lock pin 42 is located on the proximal side, the lock rod 44 is disposed at the stroke end on the radially outer side of the predetermined axis 101. The claw portion 31p is positioned by abutting against the shank portion of the tool. Each of the first locking mechanism 41A and the second locking mechanism 41B is in a locked state in which the tool held by the gripping portion 31 is held.

[0032] 1 to 4, the tool changer 21 further includes a pin connecting unit 61. The pin connecting unit 61 connects the first lock pin 42A and the second lock pin 42B to each other.

[0033] The pin coupling unit 61 slides in the axial direction of the specified shaft 101 when the first locking mechanism 41A and the second locking mechanism 41B (locking mechanism 41) operate. The pin coupling unit 61 slides in the axial direction of the specified shaft 101 from the distal side to the proximal side when the locking mechanism 41 operates from the released state to the locked state. The pin coupling unit 61 slides in the axial direction of the specified shaft 101 from the proximal side to the distal side when the locking mechanism 41 operates from the locked state to the released state.

[0034] The pin coupling unit 61 has a plate portion 62 and a plurality of rollers 63. The plate portion 62 is made of a plate material whose axial direction of the specified axis 101 corresponds to the thickness direction. The plate portion 62 is disposed around the specified axis 101. The plate portion 62 has a ring shape centered around the specified axis 101. The plate portion 62 faces the arm portion 32 with a gap in the axial direction of the specified axis 101. The plate portion 62 couples the first lock pin 42A and the second lock pin 42B to each other. The first lock pin 42A and the second lock pin 42B are connected to the plate portion 62. An end of the lock pin 42 on the proximal side in the axial direction of the specified axis 101 is connected to the plate portion 62.

[0035] The rollers 63 are attached to the plate portion 62. The rollers 63 are spaced apart in the circumferential direction of the specified shaft 101. The rollers 63 are equally spaced apart in the circumferential direction of the specified shaft 101. The rollers 63 are rotatable about a rotation axis extending in the radial direction of the specified shaft 101. The rollers 63 are arranged to protrude from the plate portion 62 at least proximally in the axial direction of the specified shaft 101. In this embodiment, the pin coupling unit 61 has two rollers 63.

[0036] The pin coupling unit 61 further includes a first pin member 66A and a second pin member 66B. Each of the pin members 66 of the first pin member 66A and the second pin member 66B is connected to a plate portion 62. The pin member 66 protrudes from the plate portion 62 toward the outside in the radial direction of the predetermined axis 101.

[0037] The first pin member 66A and the second pin member 66B are provided at angular positions offset from each other by 180° in the circumferential direction of the predetermined axis 101.

[0038] The automatic tool changer 100 further has a base member 51. The base member 51 is made of a plate material whose axial direction of the specified axis 101 corresponds to the thickness direction. The base member 51 is disposed opposite the tool changer 21 in the axial direction of the specified axis 101. The base member 51 is disposed opposite the plate portion 62 in the axial direction of the specified axis 101. The base member 51 is disposed between the plate portion 62 and a driving plate 82 described later in the axial direction of the specified axis 101.

[0039] The base member 51 is a fixed plate, and the position of the base member 51 is fixed. The base member 51 is a part that does not slide in the axial direction of the predetermined shaft 101 and does not rotate around the predetermined shaft 101 when the automatic tool changer 100 changes tools.

[0040] 1, the base member 51 comes into contact with the plurality of rollers 63 when the tool exchange unit 21 rotates about the predetermined axis 101. The plurality of rollers 63 rotate while coming into contact with the base member 51 when the tool exchange unit 21 rotates about the predetermined axis 101.

[0041] 2 to 4, the base member 51 is provided with a plurality of cutout portions 52. The cutout portions 52 are formed of through holes penetrating the base member 51 in the axial direction of the specified shaft 101. The plurality of cutout portions 52 are provided spaced apart in the circumferential direction of the specified shaft 101. The plurality of cutout portions 52 are provided corresponding to the plurality of rollers 63, respectively. The plurality of cutout portions 52 face the plurality of rollers 63 in the axial direction of the specified shaft 101 when the locking mechanism 41 operates between the released state and the locked state.

[0042] The automatic tool changer 100 further includes a locking actuator 81. The locking actuator 81 is a drive device for operating the first locking mechanism 41A and the second locking mechanism 41B (locking mechanism 41) between a released state and a locked state.

[0043] The locking actuator 81 is disposed proximal to the tool exchange unit 21 in the axial direction of the specified axis 101. The locking actuator 81 is provided on the opposite side of the locking mechanism 41 in the axial direction of the specified axis 101, with the pin coupling unit 61 (plate portion 62) in between. The locking actuator 81 is a part that does not slide in the axial direction of the specified axis 101 and does not rotate around the specified axis 101 when tools are exchanged by the automatic tool changer 100.

[0044] The locking actuator 81 has a plurality of piston cylinders 83 and a drive plate 82 .

[0045] The plurality of piston cylinders 83 are provided at intervals in the circumferential direction of the predetermined axis 101. The plurality of piston cylinders 83 are provided at equal intervals in the circumferential direction of the predetermined axis 101. The power source of the piston cylinders 83 is hydraulic pressure.

[0046] The driving plate 82 is made of a plate material whose thickness direction corresponds to the axial direction of the specified axis 101. The driving plate 82 has a ring shape centered on the specified axis 101. The driving plate 82 faces the base member 51 in the axial direction of the specified axis 101. The driving plate 82 is disposed on the opposite side of the plate portion 62 with respect to the base member 51 in the axial direction of the specified axis 101.

[0047] 2 to 4, the drive plate 82 is provided with a plurality of protrusions 82s. The protrusions 82s have a protruding shape that protrudes in the axial direction of the specified shaft 101. The protrusions 82s protrude in the axial direction of the specified shaft 101 in a direction approaching the base member 51. The plurality of protrusions 82s are provided spaced apart in the circumferential direction of the specified shaft 101. The plurality of protrusions 82s are provided corresponding to the plurality of rollers 63, respectively. When the first locking mechanism 41A and the second locking mechanism 41B are in operation, the protrusions 82s and the rollers 63 are in contact with each other through the cutout portions 52.

[0048] The piston cylinder 83 can be extended and retracted along the axial direction of the predetermined axis 101. The piston cylinder 83 has a cylinder case 85 and a piston rod 84. The piston rod 84 is combined with the cylinder case 85. The piston rod 84 extends in the axial direction of the predetermined axis 101. An end of the piston rod 84 is connected to the drive plate 82. When the piston cylinder 83 is extended, oil is supplied to a first hydraulic chamber 87 in the cylinder case 85, causing the piston rod 84 to stroke from the proximal side to the distal side in the axial direction of the predetermined axis 101. When the piston cylinder 83 is retracted, oil is supplied to a second hydraulic chamber 86 in the cylinder case 85, causing the piston rod 84 to stroke from the distal side to the proximal side in the axial direction of the predetermined axis 101.

[0049] As shown in FIG. 2 to FIG. 4, when the lock mechanism 41 moves from the released state to the locked state, the piston cylinder 83 is driven to shorten. The drive plate 82 slides from the distal side to the proximal side of the predetermined axis 101. The first lock pin 42A and the second lock pin 42B slide from the distal side to the proximal side in the axial direction of the predetermined axis 101 by the elastic force of the spring member 46 directed from the distal side to the proximal side of the predetermined axis 101. The pin coupling unit 61 that couples the first lock pin 42A and the second lock pin 42B together slides from the distal side to the proximal side of the predetermined axis 101 by the contact of the multiple rollers 63 with the drive plate 82 (multiple convex portions 82s). The lock rod 44 slides toward the radially outward direction of the predetermined axis 101 by the contact position of the tapered portion 45 with the wedge portion 43 moving from the radially inner side to the radially outer side of the predetermined axis 101. The claw portion 31p swings about the swing shaft 106 and comes into contact with the shank portion of the tool.

[0050] When the lock mechanism 41 moves from the locked state to the released state, the piston cylinder 83 is extended. The drive plate 82 slides from the proximal side to the distal side in the axial direction of the specified shaft 101. The pin coupling unit 61 slides from the proximal side to the distal side in the axial direction of the specified shaft 101 by the drive plate 82 (multiple convex portions 82s) pushing the multiple rollers 63 from the proximal side to the distal side in the axial direction of the specified shaft 101. The first lock pin 42A and the second lock pin 42B, which are integrally coupled by the pin coupling unit 61, slide from the proximal side to the distal side in the axial direction of the specified shaft 101 against the elastic force of the spring member 46. The lock rod 44 slides toward the radially inward direction of the specified shaft 101 by the contact position of the tapered portion 45 and the wedge portion 43 moving from the radially outer side to the radially inner side of the specified shaft 101. The claw portion 31p swings about the swing shaft 106 in the opposite direction to the previous case, and moves away from the shank portion of the tool.

[0051] It should be noted that the locking actuator in the present invention is not limited to the above-mentioned piston cylinder 83 driven by hydraulic pressure, and for example, a piston cylinder driven by air pressure may be used.

[0052] The automatic tool changer 100 further has a detection unit 71. The detection unit 71 is capable of detecting the position of the pin connection unit 61 in the axial direction of the specified axis 101. The detection unit 71 is provided on the opposite side of the lock mechanism 41 in the axial direction of the specified axis 101, with the pin connection unit 61 (pin member 66) in between. The detection unit 71 is a part that does not slide in the axial direction of the specified axis 101 and does not rotate around the specified axis 101 when tools are changed by the automatic tool changer 100.

[0053] The detection unit 71 has a sensor 72, a detection pin 73, and a spring member 75. The sensor 72 is a proximity sensor.

[0054] The detection pin 73 has a pin shape extending in the axial direction of the specified axis 101. The detection pin 73 has a dog 74 to be detected by the sensor 72. The detection pin 73 is supported so as to be slidable in the axial direction of the specified axis 101. The detection portion 71 (detection pin 73) is provided facing the pin member 66 in the axial direction of the specified axis 101.

[0055] The spring member 75 is provided on the detection pin 73. The spring member 75 exerts an elastic force on the detection pin 73 from the proximal side to the distal side in the axial direction of the specified axis 101. The detection pin 73 is biased against the pin member 66 in the axial direction of the specified axis 101 by the elastic force of the spring member 75.

[0056] With this configuration, the detection pin 73 slides in the axial direction of the predetermined shaft 101 together with the pin coupling unit 61 when the locking mechanism 41 operates between the released state and the locked state. In the released state of the locking mechanism 41 shown in Fig. 2, the dog 74 is disposed in a position offset from the sensor 72. In the locked state shown in Fig. 3, the dog 74 is disposed in a position facing the sensor 72.

[0057] The type of sensor used in the detection unit of the present invention is not limited to a proximity sensor, and may be, for example, a photoelectric sensor. Also, a contact type sensor such as a microswitch or a limit switch may be used.

[0058] Fig. 5 is a cross-sectional view showing a schematic diagram of a drive mechanism of the tool exchanger in Fig. 4. With reference to Figs. 1 to 5, the automatic tool changer 100 further includes a slide actuator 91 and a turning actuator 95.

[0059] The slide actuator 91 is a drive device for sliding the tool exchange unit 21 in the axial direction of a predetermined axis 101 during tool exchange. The slide actuator 91 has a motor 92, a screw 93, and a nut 94. The screw 93 and the nut 94 form a ball screw.

[0060] The motor 92 is a servo motor capable of controlling the rotation angle (position) of the motor. A screw 93 is connected to the output shaft of the motor 92. The screw 93 extends along a predetermined axis 101. The screw 93 passes through the inside of a plate portion 62 having a ring shape and extends from the proximal side to the distal side of the predetermined axis 101. A gap is provided between the screw 93 and the plate portion 62. The screw 93 can rotate in the forward direction and the reverse direction around the predetermined axis 101 by inputting the rotation from the motor 92. A nut 94 is screwed onto the screw 93. The nut 94 is connected to the tool exchange unit 21. The nut 94 can slide in the axial direction of the predetermined axis 101 as the screw 93 rotates.

[0061] In this configuration, the rotation in the forward or reverse direction output from the motor 92 is transmitted to the screw 93, causing the screw 93 to rotate about the predetermined axis 101. As the screw 93 rotates, the nut 94 slides from the proximal side to the distal side in the axial direction of the predetermined axis 101, or slides from the distal side to the proximal side in the axial direction of the predetermined axis 101. As a result, the tool exchange unit 21 connected to the nut 94 slides from the proximal side to the distal side in the axial direction of the predetermined axis 101, or slides from the distal side to the proximal side in the axial direction of the predetermined axis 101.

[0062] The turning actuator 95 is a drive device for turning the tool exchange unit 21 about a predetermined axis 101 during tool exchange. The turning actuator 95 has a motor 96, a first gear 97, a second gear 98, and a plurality of guide pins 99.

[0063] The motor 96 is a servo motor capable of controlling the rotation angle (position) of the motor. The output shaft of the motor 96 extends in a direction perpendicular to the specified axis 101. A first gear 97 is connected to the output shaft of the motor 96. The first gear 97 is a bevel gear. The second gear 98 is a bevel gear centered on the specified axis 101, and meshes with the first gear 97. A plurality of guide pins 99 are connected to the second gear 98. The plurality of guide pins 99 are provided at intervals in the circumferential direction of the specified axis 101. The guide pins 99 extend in the axial direction of the specified axis 101.

[0064] As shown in Figs. 4 and 5, the plate portion 62 is provided with a plurality of guide pin holes 64. The plurality of guide pin holes 64 are provided at intervals in the circumferential direction of the specified axis 101. The guide pin holes 64 penetrate the plate portion 62 in the axial direction of the specified axis 101. A plurality of guide pins 99 are disposed in each of the plurality of guide pin holes 64. The guide pins 99 pass through the guide pin holes 64 and extend from the proximal side to the distal side of the specified axis 101. A gap is provided between the guide pins 99 and an inner peripheral wall of the plate portion 62 that defines the guide pin holes 64.

[0065] In this configuration, rotation from the motor 96 is transmitted to the second gear 98 via the first gear 97, causing the second gear 98 to rotate about a predetermined axis 101. A plurality of guide pins 99 connected to the second gear 98 move in the circumferential direction of the predetermined axis 101. The movement of the plurality of guide pins 99 in the circumferential direction of the predetermined axis 101 is transmitted to the plate portion 62, causing the pin coupling unit 61 to rotate about the predetermined axis 101.

[0066] Meanwhile, the guide pin 99 and the plate portion 62 are relatively slidable in the axial direction of the predetermined shaft 101 with the guide pin 99 remaining disposed in the guide pin hole 64. The plate portion 62 is guided by the multiple guide pins 99 so as to be slidable in the axial direction of the predetermined shaft 101. With this configuration, when rotation is output from the motor 92 in the slide actuator 91, the plate portion 62 is capable of sliding in the axial direction of the predetermined shaft 101.

[0067] Figures 6 to 8 are cross-sectional views showing the automatic tool changer during tool change. Figures 6 to 8 show cross-sectional shapes of the automatic tool changer 100 corresponding to Figures 2 and 3. Figures 9 to 11 are front views showing the automatic tool changer during tool change. Figures 9 to 11 show the automatic tool changer 100 (tool change unit 21) as viewed from the distal side to the proximal side of a predetermined axis 101. Figure 12 is a flowchart showing steps of tool change by the automatic tool changer.

[0068] 1, 9 and 12, in the initial state of tool exchange, the tool exchange unit 21 is arranged in the home position (S110). In the home position, the tool exchange unit 21 is in a posture in which the arm unit 32 extends in the vertical direction and the second grip unit 31B and the first grip unit 31A are arranged above and below, respectively. Each of the lock mechanisms 41, the first lock mechanism 41A and the second lock mechanism 41B, is in a released state.

[0069] In an initial state of tool exchange, the multiple rollers 63 are in contact with the base member 51. The base member 51 has a first surface 51a. The first surface 51a is a plane perpendicular to the predetermined axis 101. The first surface 51a faces the distal side in the axial direction of the predetermined axis 101. The multiple rollers 63 are in contact with the first surface 51a.

[0070] A plurality of protrusions 82s are arranged in each of the plurality of cutouts 52 (state of the cutouts 52 and the protrusions 82s shown in FIG. 2). The protrusions 82s have a second surface 82a. The second surface 82a is arranged at the protruding end in the axial direction of the predetermined axis 101, and is a plane perpendicular to the predetermined axis 101. The second surface 82a faces the distal side in the axial direction of the predetermined axis 101. The first surface 51a and the second surface 82a are flush with each other. The plurality of rollers 63 are each arranged at a position spaced 90° from the plurality of cutouts 52 (the plurality of protrusions 82s) in the circumferential direction of the predetermined axis 101.

[0071] The tool pot arranged at the tool waiting position holds a first tool Ta to be used in the next machining, and the tool spindle arranged at the tool changing position in the machining area holds a second tool Tb that has finished machining.

[0072] As shown in FIG. 2, FIG. 10 and FIG. 12, next, the tool exchange unit 21 is rotated by 90° by driving the turning actuator 95 (rotation of the motor 96) (S120). When the tool exchange unit 21 is turned, the rollers 63 rotate while contacting the base member 51 (first surface 51a). When the turning operation of the tool exchange unit 21 is completed, the rollers 63 each contact the protrusions 82s (second surface 82a) respectively arranged in the cutout portions 52. The shank portion of the first tool Ta is arranged in the first gripping portion 31A, and the shank portion of the second tool Tb is arranged in the second gripping portion 31B. The detection pin 73 in the detection unit 71 faces the first pin member 66A in the axial direction of the predetermined axis 101.

[0073] As shown in FIG. 3 and FIG. 12, the clamping of the second tool Tb by the tool spindle is released, and the locking actuator 81 is driven (the piston cylinder 83 is contracted) to operate each of the locking mechanisms 41 of the first locking mechanism 41A and the second locking mechanism 41B from the release state to the lock state (S130). The plurality of convex portions 82s retract from the plurality of notches 52. The plurality of rollers 63 enter the plurality of notches 52 while maintaining a state of contact with the plurality of convex portions 82s. This allows the pin coupling unit 61 to slide from the far-sighted side to the proximal side in the axial direction of the predetermined axis 101. The detection pin 73 in the detection unit 71 slides from the far-sighted side to the proximal side in the axial direction of the predetermined axis 101 against the elastic force of the spring member 75 by being pushed by the first pin member 66A.

[0074] By arranging dog 74 in a position facing sensor 72, detection unit 71 detects the locked state of locking mechanism 41 (S140). When detection unit 71 detects the locked state of locking mechanism 41, control unit 120 provided in the machine tool proceeds with the tool replacement steps, which will be described below. When detection unit 71 does not detect the locked state of locking mechanism 41, control unit 120 stops the progress of the tool replacement steps and issues an alert to the operator.

[0075] 6, 11 and 12, next, the tool exchange part 21 is slid from the proximal side to the distal side of the predetermined axis 101 by driving the slide actuator 91 (rotating the motor 92) (S150). While the rollers 63 are separated from the drive plate 82 (the protruding parts 82s), the locked state of the lock mechanism 41 is maintained by the elastic force acting on the lock pin 42 from the spring member 46. The first tool Ta is extracted from the tool pot arranged at the tool standby position, and the second tool Tb is extracted from the tool spindle.

[0076] Next, the tool exchange unit 21 is rotated 180° by driving the turning actuator 95 (rotating the motor 96) (S160). The first tool Ta is positioned opposite the tool spindle arranged at the tool exchange position in the machining area, and the second tool Tb is positioned opposite the tool pot arranged at the tool standby position. The detection pin 73 of the detection unit 71 faces the second pin member 66B in the axial direction of the predetermined axis 101.

[0077] 7 and 12, next, the tool exchange unit 21 is slid from the distal side to the proximal side of the predetermined axis 101 by driving the slide actuator 91 (rotating the motor 92) (S170). The rollers 63 enter the cutout portions 52, respectively, and come into contact with the drive plate 82 (the convex portions 82s). The first tool Ta is inserted into the tool spindle, and the second tool Tb is inserted into the tool pot arranged at the tool standby position.

[0078] In this step, the detection of the locked state of the lock mechanism 41 by the detection unit 71 may or may not be performed.

[0079] As shown in FIG. 8 and FIG. 12, next, the first tool Ta is clamped by the tool spindle, and the locking actuator 81 is driven (the piston cylinder 83 is extended) to operate each of the locking mechanisms 41 of the first locking mechanism 41A and the second locking mechanism 41B from the locked state to the released state (S180). The rollers 63 each retract from the notches 52. The protruding parts 82s each enter the notches 52 while maintaining a state of contact with the rollers 63. This allows the pin coupling unit 61 to slide from the proximal side to the distal side in the axial direction of the specific axis 101. The second pin member 66B slides from the proximal side to the distal side of the specific axis 101. The detection pin 73 in the detection unit 71 slides from the proximal side to the distal side in the axial direction of the specific axis 101 by the elastic force of the spring member 75.

[0080] By disposing the dog 74 at a position offset from the sensor 72, the detection unit 71 detects the release state of the locking mechanism 41 (S190). When the detection unit 71 detects the release state of the locking mechanism 41, the control unit 120 proceeds with the tool replacement steps, which will be described below. When the detection unit 71 does not detect the release state of the locking mechanism 41, the control unit 120 stops the progress of the tool replacement steps and issues an alert to the operator.

[0081] 1 and 12, next, the tool exchange unit 21 is rotated 90° by driving the turning actuator 95 (rotating the motor 96) (S200). When the tool exchange unit 21 turns, the rollers 63 rotate while contacting the base member 51 (first surface 51a). The tool exchange unit 21 returns to the home position where the arm unit 32 extends in the vertical direction and the second gripping unit 31B and the first gripping unit 31A are positioned above and below, respectively. Through the above steps, tool exchange by the automatic tool changer 100 is completed.

[0082] To summarize the structure of the automatic tool changer 100 in the embodiment of the present invention described above, the automatic tool changer 100 in the embodiment includes a tool changer 21 that changes tools by sliding in the axial direction of a predetermined axis 101 and rotating about the predetermined axis 101. The tool changer 21 includes a first gripping portion 31A and a second gripping portion 31B that are provided separately in the circumferential direction of the predetermined axis 101 and each capable of gripping a tool, and a first lock pin 42A extending in the axial direction of the predetermined axis 101. The first lock mechanism 41A operates between a locked state in which the tool gripped by the first gripping portion 31A is held and a released state in which the tool gripped by the first gripping portion 31A is released in accordance with the sliding movement of the first lock pin 42A along the axial direction of the predetermined axis 101. The second lock mechanism 41A extends in the axial direction of the predetermined axis 101. The automatic tool changer 100 further includes a second lock mechanism 41B that operates between a locked state in which the tool held by the second gripping portion 31B is held and a released state in which the tool held by the second gripping portion 31B is released in response to a sliding movement of the second lock pin 42B along the axial direction of the predetermined axis 101, and a pin coupling unit 61 that couples the first lock pin 42A and the second lock pin 42B to each other and slides along the axial direction of the predetermined axis 101 when the first lock mechanism 41A and the second lock mechanism 41B are in operation. The automatic tool changer 100 further includes a detection unit 71 that can detect the position of the pin coupling unit 61 in the axial direction of the predetermined axis 101.

[0083] According to this configuration, the detection unit 71 can collectively detect the positions of the first lock pin 42A and the second lock pin 42B through detection of the position of the pin coupling unit 61. This allows accurate detection of the locked state of the tool held by the first gripping portion 31A and the second gripping portion 31B. Furthermore, the detection unit 71 can be configured simply and compactly compared to a case in which the positions of the first lock pin 42A and the second lock pin 42B are detected separately.

[0084] The pin coupling unit 61 also includes a plate portion 62 to which the first lock pin 42A and the second lock pin 42B are connected, and a plurality of rollers 63 attached to the plate portion 62 and provided spaced apart in the circumferential direction of the predetermined axis 101. The automatic tool changer 100 further includes a base member 51 that faces the plate portion 62 in the axial direction of the predetermined axis 101 and comes into contact with the plurality of rollers 63 when the tool changer 21 turns.

[0085] According to this configuration, when the tool exchange unit 21 rotates about the predetermined axis 101, the multiple rollers 63 rotate while being in contact with the base member 51. This allows the tool exchange unit 21 to rotate about the predetermined axis 101 smoothly.

[0086] The automatic tool changer 100 further includes a locking actuator 81 that has a driving plate 82 disposed on the opposite side of the plate portion 62 with respect to the base member 51 in the axial direction of the predetermined axis 101, and outputs a sliding motion along the axial direction of the predetermined axis 101 to the pin coupling unit 61 when the first locking mechanism 41A and the second locking mechanism 41B are operated. The base member 51 is provided with a notch portion 52 that penetrates in the axial direction of the predetermined axis 101. The driving plate 82 is provided with a convex portion 82s that protrudes in the axial direction of the predetermined axis 101 and faces the notch portion 52 in the axial direction of the predetermined axis 101. When the first locking mechanism 41A and the second locking mechanism 41B are operated, the convex portion 82s and the roller 63 come into contact with each other through the notch portion 52.

[0087] According to this configuration, even in a configuration in which the base member 51 is disposed between the plate portion 62 and the driving plate 82 in the axial direction of the specified axis 101, it is possible to realize a configuration in which the multiple rollers 63 come into contact with the base member 51 when the tool exchange unit 21 rotates, and the multiple rollers 63 come into contact with the multiple protrusions 82s, respectively, when the first locking mechanism 41A and the second locking mechanism 41B are operating.

[0088] In addition, in conjunction with the sliding movement of the tool exchange part 21 along the axial direction of the specific axis 101 during tool exchange, the pin connection unit 61 moves back and forth between a first position (position shown in FIG. 3) where the driving plate 82 (multiple convex portions 82s) and the multiple rollers 63 are in contact, and a second position (position shown in FIG. 6) where the driving plate 82 (multiple convex portions 82s) and the multiple rollers 63 are spaced apart.

[0089] In this configuration, even if an attempt is made to detect the positions of first lock pin 42A and second lock pin 42B by detecting the position of drive plate 82, the positions of first lock pin 42A and second lock pin 42B are not detected because drive plate 82 is not integrally connected to pin connecting unit 61. In contrast, detection unit 71 detects the position of pin connecting unit 61 that connects first lock pin 42A and second lock pin 42B to each other, and therefore can accurately detect the locked state of the tool gripped by first gripping portion 31A and second gripping portion 31B.

[0090] The pin coupling unit 61 further includes pin members 66 (66A, 66B) protruding from the plate portion 62 toward the outside in the radial direction of the predetermined axis 101. The detection portion 71 is provided facing the pin members 66 (66A, 66B) in the axial direction of the predetermined axis 101.

[0091] According to such a configuration, the detection unit 71 can be easily installed without interfering with the base member 51.

[0092] The automatic tool changer 100 in this embodiment includes a tool changer 21 that changes tools by sliding in the axial direction of a predetermined axis 101 and rotating about the predetermined axis 101, and a base member 51 that is disposed opposite the tool changer 21 in the axial direction of the predetermined axis 101. The tool changer 21 has a plurality of rollers 63 that are provided at intervals in the circumferential direction of the predetermined axis 101 and rotate in contact with the base member 51 when the tool changer 21 rotates.

[0093] According to this configuration, when the tool exchange part 21 turns, the multiple rollers 63 rotate while being in contact with the base member 51, so that the turning operation of the tool exchange part 21 can be made smooth.

[0094] The automatic tool changer 100 further includes a slide actuator 91 for outputting a slide motion along the axial direction of the predetermined axis 101 to the tool changer 21. The tool changer 21 further includes a plate portion 62 having a ring shape with a plurality of rollers 63 attached thereto and centered on the predetermined axis 101. The slide actuator 91 includes a screw 93 that extends along the predetermined axis 101, is inserted through the inside of the plate portion 62, and is capable of rotating in forward and reverse directions around the predetermined axis 101, and a nut 94 that is screwed into the screw 93 and connected to the tool changer 21.

[0095] With this configuration, the rotation of the screw 93 in the forward and reverse directions around the specified axis 101 is transmitted to the nut 94, thereby allowing the tool replacement part 21 to slide to one side or the other along the axial direction of the specified axis 101.

[0096] The automatic tool changer 100 further includes a turning actuator 95 for outputting a rotational motion along the circumferential direction of the specified axis 101 to the tool changer 21. The tool changer 21 further includes a plate portion 62 to which a plurality of rollers 63 are attached. The plate portion 62 is provided with a plurality of guide pin holes 64 that are spaced apart in the circumferential direction of the specified axis 101 and each of which penetrates in the axial direction of the specified axis 101. The turning actuator 95 has a plurality of guide pins 99 that each extend in the axial direction of the specified axis 101, are respectively disposed in the plurality of guide pin holes 64, and are movable in the circumferential direction of the specified axis 101.

[0097] According to this configuration, the movement of the multiple guide pins 99 in the circumferential direction of the specified axis 101 is transmitted to the plate portion 62, whereby the tool exchange portion 21 can be rotated about the specified axis 101.

[0098] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0099] 21 tool exchange unit, 31 gripping unit, 31A first gripping unit, 31B second gripping unit, 31p claw unit, 32 arm unit, 41 lock mechanism, 41A first lock mechanism, 41B second lock mechanism, 42 lock pin, 42A first lock pin, 42B second lock pin, 43 wedge unit, 44 lock rod, 45 tapered unit, 46, 75 spring member, 51 base member, 51a first surface, 52 notch unit, 61 pin coupling unit, 62 plate unit, 63 roller, 64 guide pin hole, 66 pin member, 66A first pin member, 66B second pin member, 71 detection unit, 72 sensor, 73 detection pin, 74 dog, 81 lock actuator, 82 drive plate, 82a second surface, 82s convex unit, 83 piston cylinder, 84 Piston rod, 85 cylinder case, 86 second hydraulic chamber, 87 first hydraulic chamber, 91 slide actuator, 92, 96 motor, 93 screw, 94 nut, 95 turning actuator, 97 first gear, 98 second gear, 99 guide pin, 100 automatic tool change device, 101 predetermined axis, 106 oscillating axis, 120 control unit, Ta first tool, Tb second tool.

Claims

1. A tool changer that changes tools by sliding in an axial direction of a predetermined axis and rotating around the predetermined axis, A first gripping portion capable of gripping a tool; A second gripping portion provided at a position spaced apart from the first gripping portion in a circumferential direction of the predetermined axis and capable of gripping a tool; a first lock mechanism including a first lock pin extending in an axial direction of the predetermined axis, the first lock mechanism operating between a locked state in which the tool held by the first gripping portion is held and a released state in which the tool held by the first gripping portion is released in accordance with a sliding movement of the first lock pin along the axial direction of the predetermined axis; a second lock mechanism including a second lock pin extending in the axial direction of the predetermined axis, the second lock mechanism operating between a locked state in which the tool held by the second gripping portion is held and a released state in which the tool held by the second gripping portion is released in accordance with a sliding movement of the second lock pin along the axial direction of the predetermined axis; a pin coupling unit that couples the first lock pin and the second lock pin to each other and slides along the axial direction of the predetermined axis when the first lock mechanism and the second lock mechanism are operated; a detection unit capable of detecting a position of the pin connection unit in an axial direction of the predetermined axis, The pin connection unit includes: a plate portion to which the first lock pin and the second lock pin are connected; a plurality of rollers attached to the plate portion and spaced apart in a circumferential direction of the predetermined axis; a base member that faces the plate portion in the axial direction of the specified axis and that comes into contact with the plurality of rollers when the tool exchange device turns.

2. a locking actuator having a drive plate disposed on the opposite side of the plate portion with respect to the base member in the axial direction of the predetermined axis, the locking actuator outputting a sliding motion along the axial direction of the predetermined axis to the pin coupling unit when the first locking mechanism and the second locking mechanism are operated; The base member is provided with a notch portion penetrating in the axial direction of the predetermined axis, the drive plate is provided with a protrusion that protrudes in an axial direction of the predetermined shaft and faces the notch in the axial direction of the predetermined shaft, The tool changing device according to claim 1 , wherein the protrusion and the roller come into contact with each other through the cutout when the first locking mechanism and the second locking mechanism are operated.

3. The pin coupling unit further includes a pin member protruding from the plate portion toward an outer side in a radial direction of the predetermined axis, The tool exchange device according to claim 1 or 2, wherein the detection portion is provided opposite the pin member in the axial direction of the predetermined axis.

4. A tool holding portion capable of holding a tool used in machining a workpiece; A machine tool comprising: a tool exchange device according to claim 1 or 2, which exchanges a tool held by the tool holding portion.

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