Automatic tool changer and machine tool

Abstract

To provide an automatic tool changer which enables smooth swiveling motion of a tool change part.SOLUTION: An automatic tool changer 100 includes: a tool change part 21 that slides in an axial direction of a predetermined axis 101 and swivels about the predetermined axis 101 to change a tool; and a base member 51 which is disposed facing the tool change part 21 in the axial direction of the predetermined axis 101. The tool change part 21 has a plurality of rollers 63 that are provided at intervals in a circumferential direction centered on the predetermined axis 101 and rotate while being in contact with the base member 51 during swiveling of the tool change part 21.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] For example, Patent Publication No. 2020-124762 (Patent Document 1) discloses an automatic tool changer device that includes a first changer arm having a first gripping portion capable of gripping a tool, and a second changer arm having a second gripping portion capable of gripping a tool. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-124762 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 includes a first gripping unit and a second gripping unit, 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] The automatic tool changer includes a tool changer that slides in the axial direction of a predetermined axis and pivots about the predetermined axis during tool change. The tool changer is required to smoothly pivot to prevent the tool from falling off during tool change.

[0006] An object of the present invention is to provide an automatic tool changer in which the turning operation of the tool changer is smoothly performed. [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 pivoting about the predetermined axis, and a base member that is arranged opposite the tool changer in the axial direction of the predetermined axis. The tool changer has a plurality of rollers that are spaced apart in the circumferential direction of the predetermined axis and rotate in contact with the base member when the tool changer pivots. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide an automatic tool changer in which the tool changer can be smoothly rotated. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view schematically showing an automatic tool changer (initial state) according to an embodiment of the present invention. [Figure 2] 1 is a cross-sectional view schematically showing an automatic tool changer (in a released state) according to an embodiment of the present invention. [Figure 3] 1 is a cross-sectional view schematically showing an automatic tool changer (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. FIG. [Figure 5] FIG. 5 is a cross-sectional view schematically showing a drive mechanism of the tool exchanger in FIG. 4. [Figure 6] FIG. 3 is a cross-sectional view showing the automatic tool changer during tool change. [Figure 7] FIG. 10 is another cross-sectional view showing the automatic tool changer during tool change. [Figure 8] FIG. 10 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. 10 is another front view showing the automatic tool changer during tool change. [Figure 11] FIG. 10 is yet another front view showing the automatic tool changer during tool change. [Figure 12] 4 is a flowchart showing steps of tool change by an automatic tool changer. DETAILED DESCRIPTION OF THE INVENTION

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

[0011] Fig. 1 is a cross-sectional view schematically showing an automatic tool changer (initial state) according to an embodiment of the present invention. Fig. 2 is a cross-sectional view schematically showing an automatic tool changer (released state) according to an embodiment of the present invention. Fig. 3 is a cross-sectional view schematically 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. Figs. 2 and 3 show cross-sectional shapes 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 rotary tool, or an AM / SM hybrid machine capable of additive manufacturing and subtractive manufacturing of a workpiece.

[0014] The automatic tool changer 100 changes tools 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 pivoting about the predetermined axis 101. In other words, when the automatic tool changer 100 changes tools, the tool changer 21 slides in the axial direction of the predetermined axis 101 and pivots about the predetermined axis 101 together with the tool to be changed.

[0016] The predetermined axis 101 is an imaginary straight line that extends horizontally in parallel with the rotation axis of the tool spindle.

[0017] The tool exchange unit 21 has a first gripping unit 31 A and a second gripping unit 31 B. The first gripping unit 31 A and the second gripping unit 31 B 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 that can receive the shank portion of the tool. The gripping portion 31 has a claw portion 31p. The claw portion 31p can swing around a swing axis 106 that is parallel to the predetermined axis 101. The claw portion 31p is provided so that it can come into contact with the shank portion of the tool gripped by the gripping portion 31.

[0019] The tool changer 21 further has an arm 32. The arm 32 extends radially outward from the predetermined axis 101 in an arm-like shape. The first grip 31A and the second grip 31B are provided at one end and the other end of the arm 32 in the radial direction of the predetermined axis 101, respectively. The first grip 31A and the second grip 31B are provided at separate positions in the circumferential direction of the predetermined axis 101. The first grip 31A and the second grip 31B are provided at angular positions offset by 180° around the predetermined axis 101.

[0020] 4, for the sake of convenience in describing 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 along 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, etc., and the direction from the distal side to the proximal side along 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, etc. With respect to the gripper 31 as a reference, the shank portion of the tool extends toward the proximal side in the axial direction of the predetermined axis 101, and the cutting portion of the tool extends toward 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, 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 that extends 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 spaced apart in the circumferential direction of the predetermined axis 101. The first lock pin 42A and the second lock pin 42B are spaced apart from each other in the angular position 180° apart around the predetermined axis 101. The first lock pin 42A is spaced apart from the first gripping portion 31A on the radially inward side of the predetermined axis 101. The second lock pin 42B is spaced apart from the second gripping portion 31B on the radially inward side of the predetermined 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 peripheral surface of the lock pin 42 facing radially outward of the predetermined axis 101. The wedge portion 43 is provided in a tapered shape so that the distance from the predetermined axis 101 to the bottom surface of the groove formed by the wedge portion 43 changes along the axial direction of the predetermined axis 101. The distance from the predetermined axis 101 to the bottom surface of the groove formed by the wedge portion 43 increases from the proximal side to the distal side in the axial direction of the predetermined axis 101.

[0026] Each of the locking mechanisms 41 of 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, from a coil spring that extends 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) so as 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 positioned on the distal side, the lock rod 44 is disposed at the stroke end radially inward 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 radially outward from the predetermined axis 101. The claw portion 31p is positioned by abutting against the shank portion of the tool. The first locking mechanism 41A and the second locking mechanism 41B are each in a locked state to hold the tool gripped by the gripping portion 31.

[0032] 1 to 4, the tool changer 21 further includes a pin coupling unit 61. The pin coupling unit 61 couples 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) are operated. When the locking mechanism 41 is operated 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 distal side to the proximal side. When the locking mechanism 41 is operated from the locked state to the released state, the pin coupling unit 61 slides in the axial direction of the specified shaft 101 from the proximal side to the distal side.

[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 thickness direction corresponds to the axial direction of the predetermined axis 101. The plate portion 62 is arranged around the predetermined axis 101. The plate portion 62 has a ring shape with the predetermined axis 101 as its center. The plate portion 62 faces the arm portion 32 with a gap in the axial direction of the predetermined 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. The end of the lock pin 42 on the proximal side in the axial direction of the predetermined 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 axis 101. The rollers 63 are equally spaced apart in the circumferential direction of the specified axis 101. The rollers 63 are rotatable about a rotation axis extending in the radial direction of the specified axis 101. The rollers 63 are arranged to protrude from the plate portion 62 at least proximally in the axial direction of the specified axis 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, 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 radially outward from the predetermined axis 101.

[0037] The first pin member 66A and the second pin member 66B are provided at angular positions offset 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 thickness direction corresponds to the axial direction of the predetermined axis 101. The base member 51 is disposed opposite the tool change unit 21 in the axial direction of the predetermined axis 101. The base member 51 is disposed opposite the plate unit 62 in the axial direction of the predetermined axis 101. The base member 51 is disposed between the plate unit 62 and a drive plate 82 (described later) in the axial direction of the predetermined 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 axis 101 or rotate around the predetermined axis 101 when tools are changed by the automatic tool changer 100.

[0040] 1, the base member 51 comes into contact with the plurality of rollers 63 when the tool changer 21 turns about the predetermined axis 101. The plurality of rollers 63 rotate while coming into contact with the base member 51 when the tool changer 21 turns 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 through-holes that penetrate the base member 51 in the axial direction of the predetermined shaft 101. The plurality of cutout portions 52 are provided spaced apart in the circumferential direction of the predetermined 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 predetermined 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 driving device for operating the first locking mechanism 41A and the second locking mechanism 41B (locking mechanism 41) between a release state and a locked state.

[0043] The locking actuator 81 is disposed proximal to the tool changer 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 or rotate around the specified axis 101 when tools are changed 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 drive plate 82 is made of a plate material whose thickness direction corresponds to the axial direction of the predetermined axis 101. The drive plate 82 has a ring shape centered on the predetermined axis 101. The drive plate 82 faces the base member 51 in the axial direction of the predetermined axis 101. The drive plate 82 is disposed on the opposite side of the base member 51 from the plate portion 62 in the axial direction of the predetermined axis 101.

[0047] As shown in FIGS. 2 to 4 , the drive plate 82 is provided with a plurality of protrusions 82s. The protrusions 82s have a convex shape that protrudes in the axial direction of the predetermined shaft 101. The protrusions 82s protrude in the axial direction of the predetermined shaft 101 toward the base member 51. The plurality of protrusions 82s are provided spaced apart in the circumferential direction of the predetermined 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 operated, the protrusions 82s and the rollers 63 come into contact with each other through the cutouts 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 FIGS. 2 to 4 , when the locking mechanism 41 moves from the released state to the locked state, the piston cylinder 83 is driven to contract. The drive plate 82 slides from the distal side toward the proximal side of the predetermined axis 101. The first lock pin 42A and the second lock pin 42B slide from the distal side toward the proximal side in the axial direction of the predetermined axis 101 due to the elastic force of the spring member 46 acting from the distal side toward the proximal side of the predetermined axis 101. The pin coupling unit 61, which integrally couples the first lock pin 42A and the second lock pin 42B, slides from the distal side toward the proximal side of the predetermined axis 101 as multiple rollers 63 come into contact with the drive plate 82 (multiple protrusions 82s). The lock rod 44 slides radially outward of the predetermined axis 101 as the contact position of the tapered portion 45 with the wedge portion 43 moves from the radially inner side to the radially outer side of the predetermined axis 101. The claw portion 31p swings around the swing shaft 106 and comes into contact with the shank portion of the tool.

[0050] When the locking 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 predetermined axis 101. The drive plate 82 (multiple protrusions 82s) pushes the multiple rollers 63 from the proximal side to the distal side in the axial direction of the predetermined axis 101, causing the pin coupling unit 61 to slide from the proximal side to the distal side in the axial direction of the predetermined axis 101. The first lock pin 42A and the second lock pin 42B, which are coupled together by the pin coupling unit 61, slide from the proximal side to the distal side in the axial direction of the predetermined axis 101 against the elastic force of the spring member 46. The contact position between the tapered portion 45 and the wedge portion 43 moves from the radially outer side to the radially inner side of the predetermined axis 101, causing the lock rod 44 to slide radially inward of the predetermined axis 101. The claw portion 31p swings around the swing shaft 106 in the opposite direction to the previous case, and moves away from the shank portion of the tool.

[0051] The locking actuator in the present invention is not limited to the above-described piston cylinder 83 driven by hydraulic pressure, but may be, for example, a piston cylinder driven by air pressure.

[0052] The automatic tool changer 100 further includes a detection unit 71. The detection unit 71 is capable of detecting the position of the pin coupling unit 61 in the axial direction of the predetermined axis 101. The detection unit 71 is provided on the opposite side of the locking mechanism 41 in the axial direction of the predetermined axis 101, with the pin coupling unit 61 (pin member 66) in between. The detection unit 71 is a part that does not slide in the axial direction of the predetermined axis 101 or rotate around the predetermined 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 predetermined axis 101. The detection pin 73 has a dog 74 that is to be detected by the sensor 72. The detection pin 73 is supported so as to be slidable in the axial direction of the predetermined axis 101. The detection portion 71 (detection pin 73) is provided opposite the pin member 66 in the axial direction of the predetermined axis 101.

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

[0056] With this configuration, the detection pin 73 slides together with the pin coupling unit 61 in the axial direction of the predetermined axis 101 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 positioned away from the sensor 72. In the locked state shown in FIG. 3, the dog 74 is positioned opposite the sensor 72.

[0057] The type of sensor used in the detection unit of the present invention is not limited to a proximity sensor, but 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 schematically showing a drive mechanism of the tool changer in Fig. 4. With reference to Figs. 1 to 5, the automatic tool changer 100 further has a slide actuator 91 and a turning actuator 95.

[0059] The slide actuator 91 is a driving device for sliding the tool changer 21 in the axial direction of a predetermined axis 101 during tool change. 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 ring-shaped plate portion 62 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 is capable of rotating in forward and reverse directions around the predetermined axis 101 by inputting rotation from the motor 92. A nut 94 is threaded onto the screw 93. The nut 94 is connected to the tool changer 21. The nut 94 is slidable in the axial direction of the predetermined axis 101 as the screw 93 rotates.

[0061] In this configuration, forward or reverse rotation 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 from the distal side to the proximal side in the axial direction of the predetermined axis 101. As a result, the tool changer 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 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 changer 21 around a predetermined axis 101 during tool change. 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 Figures 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 predetermined axis 101. The guide pin holes 64 penetrate the plate portion 62 in the axial direction of the predetermined 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 predetermined axis 101. A gap is provided between the guide pins 99 and the inner circumferential 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 around 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 around the predetermined axis 101.

[0066] Meanwhile, the guide pins 99 and the plate portion 62 are relatively slidable in the axial direction of the predetermined axis 101 with the guide pins 99 remaining positioned in the guide pin holes 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 axis 101. With this configuration, when rotation is output from the motor 92 in the slide actuator 91, the plate portion 62 is able to slide in the axial direction of the predetermined axis 101.

[0067] 6 to 8 are cross-sectional views showing the automatic tool changer during tool change. Cross-sectional shapes of the automatic tool changer 100 corresponding to those shown in FIGS. 2 and 3 are shown in FIGS. 9 to 11. Front views showing the automatic tool changer during tool change are shown in FIGS. 9 to 11. The automatic tool changer 100 (tool change unit 21) is shown viewed from the distal side to the proximal side of a predetermined axis 101. FIG. 12 is a flowchart showing the steps of tool change by the automatic tool changer.

[0068] 1, 9, and 12, in the initial state of tool change, the tool changer 21 is located at the home position (S110). At the home position, the tool changer 21 is positioned such that the arm 32 extends in the vertical direction and the second gripping portion 31B and the first gripping portion 31A are located above and below each other. The locking mechanisms 41 of the first locking mechanism 41A and the second locking mechanism 41B are in the released state.

[0069] In the initial state of tool change, 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 (the 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° apart from the plurality of cutouts 52 (the plurality of protrusions 82s) in the circumferential direction of the predetermined axis 101.

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

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

[0073] As shown in FIGS. 3 and 12, next, 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 retracted) 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 contact with the plurality of convex portions 82s. This allows the pin coupling unit 61 to slide from the distal side to the proximal side in the axial direction of the predetermined axis 101. The detection pin 73 of the detection unit 71 is pushed by the first pin member 66A, and slides from the distal side to the proximal side in the axial direction of the predetermined axis 101 against the elastic force of the spring member 75.

[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 changer 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). The rollers 63 move away from the drive plate 82 (the protrusions 82s), while the elastic force of the spring member 46 acting on the lock pin 42 maintains the locked state of the lock mechanism 41. 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 changer 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 change 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 changer 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 respectively enter the cutout portions 52 and come into contact with the drive plate 82 (the protrusions 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 unit 71 may or may not detect the locked state of the lock mechanism 41.

[0079] As shown in FIGS. 8 and 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 change 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 retract from the notches 52. The protrusions 82s enter the notches 52 while maintaining 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 predetermined axis 101. The second pin member 66B slides from the proximal side to the distal side in the axial direction of the predetermined axis 101. The detection pin 73 of the detection unit 71 slides from the proximal side to the distal side in the axial direction of the predetermined axis 101 due to 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). If 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. If 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 changer 21 is rotated 90° by driving the rotation actuator 95 (rotating the motor 96) (S200). When the tool changer 21 rotates, the rollers 63 rotate while contacting the base member 51 (first surface 51a). The tool changer 21 returns to the home position where the arm 32 extends in the vertical direction and the second gripper 31B and the first gripper 31A are positioned above and below each other. Through the above steps, tool change by the automatic tool changer 100 is completed.

[0082] To summarize the structure of the automatic tool changer 100 according to the embodiment of the present invention as described above, the automatic tool changer 100 according to 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 that extends 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 automatic tool changer 100 further includes a second locking mechanism 41B that includes a locking pin 42B and 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 accordance with the sliding movement of the second locking pin 42B along the axial direction of the predetermined axis 101, and a pin coupling unit 61 that couples the first locking pin 42A and the second locking pin 42B to each other and slides along the axial direction of the predetermined axis 101 when the first locking mechanism 41A and the second locking mechanism 41B are operating. 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] With this configuration, the detector 71 can simultaneously detect the positions of the first lock pin 42A and the second lock pin 42B by detecting the position of the pin coupling unit 61. This allows the locked state of the tool held by the first gripping portion 31A and the second gripping portion 31B to be accurately detected. Furthermore, the detector 71 can be configured more simply and compactly than when 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 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 that comes into contact with the plurality of rollers 63 when the tool changer 21 rotates.

[0085] According to this configuration, when the tool changer 21 rotates around the predetermined axis 101, the multiple rollers 63 rotate while contacting the base member 51. This allows the tool changer 21 to rotate smoothly around the predetermined axis 101.

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

[0087] According to this configuration, even in a configuration in which the base member 51 is arranged between the plate portion 62 and the drive 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 when the first locking mechanism 41A and the second locking mechanism 41B operate.

[0088] In addition, in accordance with the sliding movement of the tool changer 21 along the axial direction of the specified axis 101 during tool change, the pin coupling unit 61 moves back and forth between a first position (position shown in FIG. 3) where the drive 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 drive 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 tools gripped by first gripping portion 31A and second gripping portion 31B.

[0090] The pin coupling unit 61 further includes pin members 66 (66A, 66B) that protrude from the plate portion 62 radially outward of the predetermined axis 101. The detection portion 71 is provided opposite the pin members 66 (66A, 66B) in the axial direction of the predetermined axis 101.

[0091] According to this 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 around 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 spaced apart 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 changer 21 turns, the rollers 63 rotate while contacting the base member 51, so that the tool changer 21 can turn smoothly.

[0094] The automatic tool changer 100 also 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 ring-shaped plate portion 62 having 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 inside the plate portion 62, and is rotatable in forward and reverse directions around the predetermined axis 101, and a nut 94 that is threaded onto 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, allowing the tool changer 21 to slide to one side or the other along the axial direction of the specified axis 101.

[0096] The automatic tool changer 100 also includes a turning actuator 95 for outputting rotational motion to the tool changer 21 along the circumferential direction of the predetermined axis 101. 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 predetermined axis 101 and that each penetrates in the axial direction of the predetermined axis 101. The turning actuator 95 has a plurality of guide pins 99 that each extend in the axial direction of the predetermined axis 101, are respectively disposed in the plurality of guide pin holes 64, and are movable in the circumferential direction of the predetermined axis 101.

[0097] According to this configuration, 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, so that the tool changer 21 can be rotated around the predetermined axis 101.

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

[0099] 21 tool change unit, 31 gripping unit, 31A first gripping unit, 31B second gripping unit, 31p claw unit, 32 arm unit, 41 locking mechanism, 41A first locking mechanism, 41B second locking mechanism, 42 lock pin, 42A first locking pin, 42B second locking 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 locking 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 swing 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 base member disposed opposite the tool exchange unit in the axial direction of the predetermined axis, The tool changer has a plurality of rollers that are spaced apart in a circumferential direction of the predetermined axis and that rotate while contacting the base member when the tool changer rotates.

2. a slide actuator for outputting a slide movement along the axial direction of the predetermined axis to the tool changer, the tool exchange unit further includes a plate portion having a ring shape centered on the predetermined axis and to which the plurality of rollers are attached, The slide actuator is a screw extending along the predetermined axis, inserted through the inside of the plate portion, and rotatable in forward and reverse directions around the predetermined axis; 2. The automatic tool changer according to claim 1, further comprising: a nut that is threaded onto the screw and connected to the tool changer.

3. a turning actuator for outputting a rotational motion along a circumferential direction of the predetermined axis to the tool changing unit, the tool changing unit further includes a plate unit to which the rollers are attached; The plate portion is provided with a plurality of guide pin holes spaced apart in a circumferential direction of the predetermined shaft, each of which penetrates in an axial direction of the predetermined shaft, 3. The automatic tool changer according to claim 1, wherein the turning actuator has a plurality of guide pins, each extending in the axial direction of the predetermined axis, arranged in a plurality of the guide pin holes, and movable in the circumferential direction of the predetermined axis.

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