Parallel link robot and robot system

Abstract

A parallel link robot includes a base section, a movable section (3) disposed below the base section, a plurality of arms connecting the base section and the movable section (3) in parallel, and a wrist shaft (5) penetrating the movable section (3) along an axis (A) extending in the vertical direction and rotationally driven around the axis (A) relative to the movable section (3). A jig mounting section is provided on one of an upper surface (3a) of the movable section (3) or an upper portion of the wrist shaft (5) exposed to the upper surface (3a), and a positioning jig (10) is detachably mounted to the jig mounting section. On the other of the movable section (3) or the wrist shaft (5), a contacted surface (51) that contacts the positioning jig (10) mounted to the jig mounting section is provided, or a contacted member provided with the contacted surface (51) is detachably mountable. In a state in which the positioning jig (10) mounted to the jig mounting section contacts the contacted surface (51), a predetermined phase of the wrist shaft (5) around the axis (A) relative to the movable section (3) can be detected using the positioning jig (10).

Description

Technical Field

[0001] This disclosure relates to parallel linkage robots and robot systems. Background Technology

[0002] A parallel linkage robot is known to have a pair of marks on the upper surface of the movable part and on the outer peripheral surface of the wrist axis, which is supported on the movable part in a manner that allows it to rotate about a vertical axis (see, for example, Patent Document 1). Phase alignment of the movable part and the wrist axis is performed by an operator rotating the wrist axis relative to the movable part and visually confirming that the pair of marks are aligned. By achieving phase alignment above the movable part, phase alignment can be easily performed without removing the hand or other parts such as the wrist flange mounted on the lower part of the wrist axis.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2019-119017 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] Workers visually confirmed that a pair of identical markings had a large error.

[0008] Therefore, it is desirable to be able to align the movable part with the wrist axis with high precision and ease without removing the hand or other components mounted on the wrist axis.

[0009] Solution for solving the problem

[0010] One aspect of this disclosure is a parallel linkage robot comprising: a base; a movable part disposed below the base; a plurality of arms connected in parallel to the base and the movable part; and a wrist axis extending through the movable part along an axis extending in a vertical direction and driven to rotate about the axis relative to the movable part. A clamp mounting portion is provided on either the upper surface of the movable part or the upper part of the wrist axis exposed on the upper surface, wherein a positioning clamp is detachably mounted on the clamp mounting portion. On the other side of the movable part or the wrist axis, a contact surface is provided for contacting the positioning clamp mounted on the clamp mounting portion, or a contact member having the contact surface can be detachably mounted. When the positioning clamp mounted on the clamp mounting portion is in contact with the contact surface, a predetermined phase of the wrist axis relative to the movable part about the axis can be detected by the positioning clamp. Attached Figure Description

[0011] Figure 1This is a perspective view illustrating a parallel linkage robot according to one embodiment of the present disclosure.

[0012] Figure 2 It is shown in Figure 1 A top view of the movable component of the robot system of this disclosure, which is a parallel linkage robot equipped with a positioning gripper.

[0013] Figure 3 It is shown Figure 1 A three-dimensional view of the movable components and the wrist axis component.

[0014] Figure 4 It is shown Figure 2 A three-dimensional view of an example positioning fixture for a robotic system.

[0015] Figure 5 It is shown in Figure 2 An exploded perspective view of a method for mounting a support to a movable component of a parallel linkage robot in a first variation of the robot system.

[0016] Figure 6 It is shown Figure 2 A top view of the movable component in the second variant of the robot system.

[0017] Figure 7 It is shown Figure 2 A top view of the movable component in the third variation of the robot system.

[0018] Figure 8 It is shown Figure 2 A partial three-dimensional view of the movable component in the fourth variation of the robot system. Detailed Implementation

[0019] The following description, with reference to the accompanying drawings, illustrates a parallel linkage robot 1 and a robot system 100 according to one embodiment of the present disclosure.

[0020] like Figure 1 and Figure 2 As shown, the robot system 100 of this embodiment includes a parallel linkage robot 1 and a positioning fixture 10 detachably mounted on the parallel linkage robot 1.

[0021] like Figure 1 As shown, the parallel linkage robot 1 has a base 2, a movable member (movable part) 3 with a flat upper surface disposed below the base 2, and three arms 4 for connecting the base 2 and the movable member 3 in parallel. Furthermore, the parallel linkage robot 1 includes a wrist axis member (wrist axis) 5, which is supported on the movable member 3 in a manner that allows it to rotate about a rotation axis (axis) A, which passes through the center of the movable member 3 in the vertical direction.

[0022] The base 2 is fixed to the housing 21 and has three arm actuators 22 that drive the three arms 4 respectively. The housing 21 is fixed to an external structure such as a ceiling or platform (not shown). The three arm actuators 22 are arranged at equal intervals around the vertical axis B passing through the center of the base 2.

[0023] Each arm 4 has a drive link 41 and two parallel driven links 42. One end of the drive link 41 is fixed to the rotation drive shaft of any arm actuator 22, and one end of each of the two parallel driven links 42 is connected to the other end of the drive link 41 via a spherical bearing 61. Furthermore, a wrist actuator 70 is mounted on one of the three arms 4. The wrist actuator 70 and the gear 71 that rotates the wrist shaft member 5 (described later) are connected via a drive shaft 73, clamped by a universal joint 72.

[0024] like Figures 1 to 3 As shown, the movable member 3 is formed in an annular shape with a hollow portion 3h extending along the rotation axis A. Furthermore, the other end of each driven link 42 of each arm 4 is connected to the movable member 3 via a spherical bearing 62. Thus, by synchronously controlling the three arm actuators 22 arranged in the base 2, the movable member 3 moves in three dimensions while maintaining a horizontal orientation.

[0025] like Figure 3 As shown, the upper surface 3a of the movable member 3 is provided with a mounting surface (clamp mounting part) 30 extending along a plane orthogonal to the rotation axis A. The mounting surface 30 is provided with two threaded holes 31 and two pin holes 32 extending parallel to the rotation axis A.

[0026] The wrist shaft member 5 is disposed within the hollow portion 3h and rotates relative to the movable member 3 about the rotation axis A using the driving force transmitted from the wrist actuator 70 via the drive shaft 73, the universal joint 72, and the gear 71. The wrist shaft member 5 passes through the movable member 3 in the direction along the rotation axis A, with its upper end protruding above the movable member 3 and its lower end protruding below the movable member 3.

[0027] A protrusion 50 is provided at the upper end of the wrist shaft member 5, which protrudes above the movable member 3. A portion of the cylindrical upper end of the protrusion 50 protrudes upward in the circumferential direction. A contact surface 51 is provided at one end of the protrusion 50 in the circumferential direction, which is arranged along a plane containing the axis of rotation A.

[0028] A flange 52 for mounting a tool such as a hand (not shown) is provided at the lower end of the wrist shaft member 5. The wrist shaft member 5 has a central hole 5h that extends along the axis of rotation A. Linear objects such as pipes or cables (not shown) can be guided from the base part 2 to the tool through the central hole 5h.

[0029] like Figures 2 to 4As shown, the positioning fixture 10 includes: a bracket 11, which is mounted on the mounting surface 30 of the movable member 3; and a dial indicator (detector) 15, which is fixed to the bracket 11 in a positioning state.

[0030] The bracket 11 includes: a flat mounting portion 12 that is in close contact with the mounting base surface 30; and a flat wall portion 13 that is connected to the mounting portion 12 and on which a dial indicator 15 is mounted.

[0031] The mounting portion 12 is provided with two through holes 12a and two pin holes 12b that extend along the thickness direction of the plate. In addition, the wall portion 13 is provided with: a through hole 13a that extends along the thickness direction of the plate so that the rod 15a of the dial indicator 15 passes through; and a threaded hole (not shown) that extends from the outside of the wall portion 13 to the inner surface of the through hole 13a and secures the locking screw 13b.

[0032] The dial indicator 15 is fixed to the wall 13 by pressing the rod 15a, which passes through the through hole 13a, with the stop screw 13b fastened to the threaded hole. The long axis of the rod 15a is aligned with the reference plane 13c of the wall 13. In this state, when the measuring head 15b at the front end of the rod 15a protrudes from the wall 13 by a predetermined amount, the reading of the dial indicator 15 is adjusted to zero.

[0033] To install the positioning clamp 10 onto the movable member 3, the mounting portion 12 of the bracket 11, on which the dial indicator 15 is mounted, is pressed tightly against the mounting surface 30, and two pins (not shown) are engaged with the pin holes 12b of the mounting portion 12 and the pin holes 32 of the mounting surface 30, respectively. Furthermore, by tightening two bolts (not shown) that pass through the two through holes 12a of the mounting portion 12 into the threaded holes 31 of the mounting surface 30, the bracket 11 is fixed to the mounting surface 30 in a positioned state.

[0034] In this state, the reference surface 13c of the wall portion 13 is positioned parallel to the contact surface 51 at a predetermined interval. The contact surface 51 is the surface that is contacted when the phase of the wrist shaft member 5 relative to the movable member 3 about the rotation axis A is aligned with a predetermined phase. Furthermore, in this state, the measuring head 15b, located at the front end of the lever 15a of the dial indicator 15, is positioned on the rotation track of the contact surface 51 about the rotation axis A.

[0035] The following explains the function of the parallel linkage robot 1 and robot system 100 configured as described in this embodiment.

[0036] With the movable component 3 and wrist axis component 5 of the parallel linkage robot 1 in phase alignment around the rotation axis A, the positioning fixture 10 is mounted to the mounting surface 30 provided on the upper surface 3a of the movable component 3 using two pins and bolts.

[0037] The position of the dial indicator 15 along the mounting surface 30 is uniquely determined by two pins. That is, the long axis of the rod 15a of the dial indicator 15 is arranged tangentially to the rotation track of the protrusion 50 of the wrist axis member 5.

[0038] In this state, the wrist axis member 5 is rotated relative to the movable member 3 about the rotation axis A, and the contact surface 51 provided on the protrusion 50 is brought into contact with the measuring head 15b of the dial indicator 15. Furthermore, by stopping the rotation of the wrist axis member 5 at the position where the reading of the dial indicator 15 is zero, the phase of the wrist axis member 5 relative to the movable member 3 can be aligned with a predetermined phase with high precision.

[0039] Then, in this state, for the control device (not shown) that controls the parallel linkage robot 1, the phase alignment between the movable member 3 and the wrist axis member 5 is completed by setting the phase of the wrist axis member 5 relative to the movable member 3 around the rotation axis A to 0°.

[0040] In this case, according to this embodiment, the positioning jig 10 fixed to the upper surface 3a of the movable member 3 can be used to perform phase alignment between the movable member 3 and the wrist shaft member 5. Therefore, it has the following advantages: the operator can easily perform phase alignment without removing the tool mounted on the flange 52, and the positioning jig 10 can be used to perform phase alignment with high precision.

[0041] In addition, in this embodiment, the positioning clamp 10 is fixed to the mounting surface 30 with two bolts, but it can also be fixed with one bolt.

[0042] Furthermore, in this embodiment, two pins are used to position the positioning clamp 10 relative to the mounting surface 30. Alternatively, the bracket 11 can be positioned using a pin and an abutting surface that abuts in one direction along the mounting surface 30, or two abutting surfaces that abut in two directions along the mounting surface 30.

[0043] In addition, in this embodiment, the mounting surface 30 is arranged along a plane orthogonal to the rotation axis A, but instead, as shown below... Figure 5 As shown, a mounting surface 30 parallel to the plane containing the axis of rotation A can also be used. In this case, the bracket 11 can be configured as a simple flat plate, and the positioning pins or abutment surfaces can be removed.

[0044] Furthermore, in this embodiment, a positioning clamp 10 equipped with a dial indicator 15 is illustrated, but instead, as... Figure 6 As shown, the positioning fixture 10 can also be formed by a block 20 that directly abuts against the contact surface 51.

[0045] Block 20 includes a mounting portion 20a, which is used to fix block 20 to the mounting seat surface 30 of the upper surface 3a of movable member 3 in a positioning state. In addition, block 20 also includes an abutment surface (abutment member) 20b, which abuts against the contact surface 51 when the wrist shaft member 5 is positioned relative to movable member 3 at a predetermined phase around the rotation axis A, with block 20 fixed to the mounting seat surface 30.

[0046] With block 20 fixed to the mounting surface 30 in a positioned state, the wrist shaft member 5 is rotated relative to the movable member 3 about the rotation axis A, causing the contact surface 51 to approach the abutment surface 20b of block 20. Furthermore, when the abutment surface 20b abuts against the contact surface 51, the wrist shaft member 5 is aligned with a predetermined phase relative to the movable member 3. The operator can visually confirm that phase alignment has been achieved through the contact between the contact surface 51 and the abutment surface 20b.

[0047] Figure 6 The example shown is a block 20 formed in an L-shape, but it is not limited to this. As long as it has the same mounting part 20a and abutment surface 20b as described above, the block 20 can be any shape.

[0048] Furthermore, in this embodiment, a contact surface 51 is provided on the protrusion 50 that protrudes upward from the upper end of the wrist shaft member 5. Instead, as... Figure 7 As shown, the contact surface 51 can also be provided on the contact member 55, which is mounted on the upper end of the wrist shaft member 5 in a detachable and positioned state. The contact member 55 can have a shape that protrudes radially outward in a cantilever beam shape than the outer peripheral surface of the upper end of the wrist shaft member 5.

[0049] Therefore, the dial indicator 15 or the contact surface 20b of the positioning fixture 10 can be made to contact the contact surface 51 at a position that is radially outward relative to the outer surface of the wrist shaft member 5. By making the contact position between the contact surface 51 and the positioning fixture 10 away from the axis of rotation A, the amount of movement of the contact surface 51 relative to the rotation angle can be increased, and the accuracy of phase alignment can be improved.

[0050] In this case, the component mounted on the upper end of the wrist shaft member 5 serves as the contacted component 55, and the component mounted on the upper surface 3a of the movable member 3 serves as the positioning clamp 10. However, the functions of the contacted component 55 and the positioning clamp 10 can be interchanged. That is, the component mounted on the upper end of the wrist shaft member 5 and protruding radially outward in a cantilever beam shape can serve as the positioning clamp 10, and the component mounted on the upper surface of the movable member 3 can serve as the contacted component 55. In this case, the mounting surface 30 for mounting the positioning clamp 10 is disposed on the upper surface of the wrist shaft member 5.

[0051] In addition, such as Figure 8 As shown, a wall portion 36, adjacent to the outer peripheral surface (wall portion) 56 of the wrist shaft member 5 with a small gap, is provided on the movable member 3. The wrist shaft member 5 and the wall portion 36 can each be provided with pin holes 57 and 37 that penetrate radially and are coaxially arranged in a predetermined phase. Furthermore, as a positioning clamp 10, a pin can be used to engage with the pin holes 57 and 37 in a manner that allows axial movement.

[0052] In this case, for example, the positioning clamp 10 is pre-fitted into the pin hole 37 of the wall portion 36, and the wrist shaft member 5 is rotated relative to the movable member 3. When the positioning clamp 10 is also fitted into the pin hole 57 of the wrist shaft member 5, the wrist shaft member 5 and the movable member 3 are aligned to a predetermined phase. Furthermore, in this case, the inner circumferential surface of the pin hole 57 of the wrist shaft member 5 functions as the contact surface for the pin of the positioning clamp 10 to contact.

[0053] Operators can easily confirm that phase alignment is completed when the positioning fixture 10 simultaneously engages with the two pin holes 37 and 57.

[0054] The wall portion 36 can be provided on a portion of the circumference around the axis of rotation A, or it can be provided on the entire circumference. Alternatively, it can be combined with... Figure 3 Similarly, the bracket 11, which forms the wall portion 36 with pin holes, is mounted in a positioned state on the mounting surface 30 provided on the movable member 3.

[0055] Explanation of reference numerals in the attached figures:

[0056] 1: Parallel Linkage Robot

[0057] 10: Positioning clamp

[0058] 15: Dial gauge (detector)

[0059] 100: Robotic Systems

[0060] 2: Basic Department

[0061] 20b: Abutment surface (abutment component)

[0062] 3: Movable components (movable parts)

[0063] 3a: Upper surface

[0064] 30: Mounting surface (clamp mounting section)

[0065] 36: Wall

[0066] 37: Pin hole

[0067] 4: Arm

[0068] 5: Wrist pivot component (wrist pivot)

[0069] 51: The surface being contacted

[0070] 55: The component being contacted

[0071] 56: Outer peripheral surface (wall part)

[0072] 57: Pin hole

[0073] A: Axis of rotation (axis)

Claims

1. A parallel link robot, characterized by, Possessing: a base section; a movable section disposed below the base section; a plurality of arms connecting the base section and the movable section in parallel; and a wrist shaft that penetrates the movable section along an axis extending in the vertical direction and is rotationally driven about the axis relative to the movable section, a jig mounting section is provided on one of the upper surface of the movable section or the upper portion of the wrist shaft exposed to the upper surface, the jig mounting section detachably mounting a positioning jig, on the other of the movable section or the wrist shaft, a contacted surface that contacts the positioning jig mounted on the jig mounting section is provided, or a contacted member provided with the contacted surface is detachably mountable, when the positioning jig mounted on the jig mounting section is brought into contact with the contacted surface while the wrist shaft is rotated about the axis relative to the movable section, a predetermined phase of the wrist shaft about the axis relative to the movable section is detected by the positioning jig.

2. A robot system, characterized in that Possessing: the parallel link robot of claim 1; and the positioning jig mounted to the jig mounting section.

3. The robot system according to claim 2, characterized in that the positioning jig is provided with a micrometer having a measurement head, when the measurement head is brought into contact with the contacted surface while the wrist shaft is rotated about the axis relative to the movable section, the predetermined phase is detected by a reading of the micrometer.

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