Parallel link mechanism and link actuation device

Abstract

To provide a parallel link mechanism, where the adjustment work is facilitated, and a link actuation device.SOLUTION: A parallel link mechanism comprises a base end side link hub, a shaft member, three or more rotators, three or more link mechanisms, and a distal end side link hub. The rotators are coupled to the base end side link hub around a rotation center axis by the shaft member while being arranged in such a manner that rotation center axes coincide with each other. A first link member of the link mechanism is fixed to one of the rotators. The first link member is rotatably coupled to a second link member in a first rotation pair part, and the second link member is rotatably coupled to the distal end side link hub in a second rotation pair part. A first rotation axis of the first rotation pair part and a second rotation axis of the second rotation pair part cross a rotation center axis of the rotator at a spherical surface link central point. A mounting part of the distal end side link hub is capable of adjusting a position of a work body in such a manner that an actuation point of the work body coincides with the spherical surface link central point.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a parallel link mechanism and a link actuator. [Background technology]

[0002] Parallel link mechanisms used in various devices have been known. For example, the parallel link mechanism described in JP 2020-153494 A (Patent Document 1) includes a base-end link hub, a tip-end link hub, and multiple link mechanisms. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-153494 Summary of the Invention [Problem to be solved by the invention]

[0004] In various devices, a working body that performs work is attached to a tip-side link hub of a parallel link mechanism. Conventional parallel link mechanisms have room for improvement in terms of ease of adjustment of the movement of the working body. This disclosure proposes technology for facilitating adjustment work for parallel link mechanisms and link actuators. [Means for solving the problem]

[0005] A parallel link mechanism according to an embodiment of the present disclosure is a parallel link mechanism on which a working vehicle is mounted. The parallel link mechanism includes a base-side link hub, a shaft member, three or more rotating bodies, three or more link mechanisms, and a tip-side link hub. The three or more rotating bodies are arranged side by side so that their respective central rotation axes coincide, and are connected to the base-side link hub by the shaft member so as to be rotatable about their central rotation axes. Each of the three or more link mechanisms includes a first link member and a second link member. The first link member of each of the three or more link mechanisms is fixed to one of the three or more rotating bodies. In each of the three or more link mechanisms, the first link member is rotatably connected to the second link member at a first rotation pair, and the second link member is rotatably connected to the tip-side link hub at a second rotation pair. The first rotation axis of the first rotation pair and the second rotation axis of the second rotation pair of each of the three or more link mechanisms intersect with the rotation central axes of the three or more rotating bodies at a spherical link center point. The distal link hub includes a mounting portion to which the working body is attached, and the mounting portion is capable of adjusting the position of the working body so that the point of application of the working body coincides with the center point of the spherical link.

[0006] The parallel link mechanism may further include a working body attached to the attachment portion, wherein the point of application of the working body coincides with the center point of the spherical link.

[0007] In the parallel link mechanism, the tip-side link hub may have a first surface facing the spherical link center point. The tip-side link hub may have a through hole opening to the first surface. The attachment portion may be provided to hold a working body at least a portion of which is passed through the through hole.

[0008] A parallel link mechanism according to another embodiment of the present disclosure includes a base-side link hub, a shaft member, three or more rotating bodies, three or more link mechanisms, a tip-side link hub, and a working body attached to the tip-side link hub. The three or more rotating bodies are arranged side by side so that their respective central rotation axes coincide, and are rotatably connected to the base-side link hub by the shaft member around their central rotation axes. Each of the three or more link mechanisms includes a first link member and a second link member. The first link member of each of the three or more link mechanisms is fixed to one of the three or more rotating bodies. In each of the three or more link mechanisms, the first link member is rotatably connected to the second link member at a first rotation pair, and the second link member is rotatably connected to the tip-side link hub at a second rotation pair. The first rotation axis of the first rotation pair and the second rotation axis of the second rotation pair of each of the three or more link mechanisms intersect with the rotation central axes of the three or more rotating bodies at a spherical link center point. The point of action of the working body coincides with the center point of the spherical link.

[0009] In the parallel link mechanism, the tip-side link hub may have a first surface facing the center point of the spherical link. A through hole opening to the first surface may be formed in the tip-side link hub. At least a portion of the working body may be passed through the through hole.

[0010] In the parallel link mechanism, at least a portion of the second rotation pair of each of the three or more link mechanisms may be disposed closer to the spherical link center point than the first surface in a direction perpendicular to the first surface.

[0011] In the parallel link mechanism, the working body may be an optical sensor, and the focal point of the optical sensor as the point of action coincides with the center point of the spherical link.

[0012] The link actuation device according to the present disclosure includes the parallel link mechanism, a first drive source that rotates a first rotating body among the three or more rotating bodies around a central axis of rotation, and a second drive source that rotates a second rotating body among the three or more rotating bodies around a central axis of rotation.

[0013] The link actuation device may further include a first rotation transmission member disposed between the first rotating body and the base-end link hub in the direction along the rotation central axis, a first connecting member connecting the first rotation transmission member to the first rotation transmission member, a second rotation transmission member disposed between the second rotating body and the base-end link hub in the direction along the rotation central axis, and a second connecting member connecting the second rotating body to the second rotation transmission member. The first rotating body, the second rotating body, the second rotation transmission member, and the first rotation transmission member may be arranged in sequence along the rotation central axis. The shaft member, the first connecting member, and the second connecting member may be arranged in sequence radially relative to the rotation central axis. [Effects of the Invention]

[0014] According to the present disclosure, it is possible to facilitate the adjustment of the movement of the working body in a parallel link mechanism and a link actuator. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 2 is a perspective view for explaining the parallel link mechanism according to the first embodiment. [Figure 2] FIG. 2 is a side view of the parallel link mechanism shown in FIG. [Figure 3] FIG. 2 is a top view of the parallel link mechanism shown in FIG. [Figure 4] FIG. 4 is a partially enlarged cross-sectional view taken along the arrows IV-IV in FIG. 3. [Figure 5] FIG. 10 is a perspective view for explaining a parallel link mechanism according to a second embodiment. [Figure 6] FIG. 10 is a side view for explaining a parallel link mechanism according to a second embodiment. [Figure 7] 10 is a cross-sectional view illustrating a rotating body, a rotation transmission member, and a connecting member of a parallel link mechanism according to a second embodiment. FIG. [Figure 8] FIG. 10 is a partially enlarged cross-sectional view for explaining a link actuation device according to a third embodiment. [Figure 9] FIG. 10 is a perspective view for explaining a link actuation device according to a fourth embodiment. [Figure 10] FIG. 10 is a side view for explaining a link actuation device according to a fourth embodiment. [Figure 11] FIG. 11 is a side view for explaining a link actuation device according to a fifth embodiment. [Figure 12] 1 is a perspective view showing an example of a link actuation device according to the present disclosure, the link actuation device including a dispenser that dispenses a fluid such as grease as a working body. FIG. [Figure 13] FIG. 13 is a side view of the link actuator shown in FIG. 12. [Figure 14] FIG. 13 is a top view of the link actuator shown in FIG. 12. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The same reference numerals are used to designate the same components, and the description thereof will not be repeated.

[0017] (Embodiment 1) <Configuration of parallel link mechanism> Fig. 1 is a perspective view for explaining a parallel link mechanism and a link actuation device according to embodiment 1. Fig. 2 is a side view of the parallel link mechanism shown in Fig. 1. Fig. 3 is a top view of the parallel link mechanism shown in Fig. 1. Fig. 4 is a partially enlarged cross-sectional view taken along arrows IV-IV in Fig. 3.

[0018] The parallel link mechanism 101 according to the first embodiment shown in Figures 1 to 4 is intended to be mounted on various types of equipment. In the various types of equipment, the parallel link mechanism 101 is intended to mount a working body 100.

[0019] 1 to 3, the parallel link mechanism 101 includes a base-end link hub 10, a shaft member 20, three rotating bodies 30a to 30c, three link mechanisms 40a to 40c, and a tip-end link hub 50. Note that in Fig. 4, only the tip-end link hub 50 and the working body 100 are shown.

[0020] The base-end link hub 10 is, for example, a plate-shaped member. The base-end link hub 10 can be attached to, for example, a part of various devices (for example, the end of a robot arm) on which the parallel link mechanism 101 is mounted. The base-end link hub 10 may be a part of various devices on which the parallel link mechanism 101 is mounted. The base-end link hub 10 has a through-hole formed therein, through which the shaft member 20 is passed, for example.

[0021] The shaft member 20 is fixed to the base-end link hub 10. The shaft member 20 connects the three rotating bodies 30a to 30c to the base-end link hub 10 so that they can rotate around a central rotation axis.

[0022] The shaft member 20 has, for example, a bolt 21 and a nut 22. The bolt 21 has a head and an externally threaded portion. The externally threaded portion has a base portion connected to the head and a tip portion located on the opposite side of the base portion. The head of the bolt 21 is disposed, for example, on the opposite side of the base-end link hub 10 with respect to the three rotating bodies 30a to 30c. The externally threaded portion of the bolt 21 is passed, for example, through holes provided in each of the three rotating bodies 30a to 30c and a through hole provided in the base-end link hub 10. The tip of the externally threaded portion of the bolt 21 protrudes on the opposite side of the base-end link hub 10 from the three rotating bodies 30a to 30c. The nut 22 is fastened to the tip of the externally threaded portion of the bolt 21.

[0023] The head of bolt 21 may be arranged on the opposite side of base-side link hub 10 from the three rotating bodies 30a to 30c, and the tip of the male threaded portion of bolt 21 may be arranged on the opposite side of base-side link hub 10 from the three rotating bodies 30a to 30c. Shaft member 20 may not have nut 22. The base-side link hub 10 may be provided with a screw hole that screws into the tip of the male threaded portion of bolt 21.

[0024] The method for fixing the shaft member 20 to the proximal link hub 10 may be any fixing method and is not limited to the fastening method described above. The shaft member 20 may be fixed to the proximal link hub 10 by, for example, crimping, welding, adhesive, or the like.

[0025] The three rotating bodies 30a to 30c are a first rotating body 30a, a second rotating body 30b, and a third rotating body 30c. Each of the first rotating body 30a, the second rotating body 30b, and the third rotating body 30c is rotatable around a rotation central axis CA1. The first rotating body 30a, the second rotating body 30b, and the third rotating body 30c are stacked in a direction along the rotation central axis CA1 so that their respective rotation central axes CA1 coincide. The first rotating body 30a is disposed closest to the distal link hub 50 among the three rotating bodies 30a to 30c. The third rotating body 30c is disposed closest to the proximal link hub 10 among the three rotating bodies 30a to 30c. The second rotating body 30b is disposed between the first rotating body 30a and the third rotating body 30c.

[0026] Each of the first rotating body 30a, the second rotating body 30b, and the third rotating body 30c is, for example, a plate-shaped member. Each of the first rotating body 30a, the second rotating body 30b, and the third rotating body 30c has a through-hole. The through-holes of the first rotating body 30a, the second rotating body 30b, and the third rotating body 30c overlap each other in the direction along the central axis of rotation CA1. A shaft member 20 passes through the through-hole of each of the first rotating body 30a, the second rotating body 30b, and the third rotating body 30c. Bearings (not shown) are disposed between the shaft member 20 and the through-holes of the first rotating body 30a, the second rotating body 30b, and the third rotating body 30c. The bearings reduce friction between the shaft member 20 and each of the first rotating body 30a, the second rotating body 30b, and the third rotating body 30c. The bearings are, for example, rolling bearings.

[0027] Each of the first rotating body 30a, the second rotating body 30b, and the third rotating body 30c has protruding portions 31a to 31c that protrude further radially relative to the central rotation axis CA1 than the other portions. As shown in Fig. 3, in a plan view, each of the protruding portions 31a to 31c of the first rotating body 30a, the second rotating body 30b, and the third rotating body 30c extends outward from the distal link hub 50. In this specification, "plan view" refers to a field of view seen from the distal link hub 50 side in a direction along the central rotation axis CA1. A screw hole, for example, is provided on the outer peripheral surface of each of the protruding portions 31a to 31c.

[0028] The relative positions of the base-side link hub 10, the first rotating body 30a, the second rotating body 30b, and the third rotating body 30c in the direction along the rotation center axis CA1 are restricted by, for example, a plurality of positioning members 32 (see FIG. 2). At least one positioning member 32 is disposed, for example, between the inner rings of the bearings disposed in the through holes of the first rotating body 30a and the second rotating body 30b. At least one positioning member 32 is disposed, for example, between the inner rings of the bearings disposed in the through holes of the second rotating body 30b and the third rotating body 30c. At least one positioning member 32 is disposed, for example, between the base-side link hub 10 and the inner ring of the bearing disposed in the through hole of the third rotating body 30c.

[0029] Each of the three link mechanisms 40a to 40c includes a first link member 41a to 41c and a second link member 42a to 42c.

[0030] One end of each of the first link members 41a to 41c is fixed to the protrusions 31a to 31c of the three rotating bodies 30a to 30c, respectively. One end of the first link member 41a is fixed to the protrusion 31a of the first rotating body 30a. One end of the first link member 41b is fixed to the protrusion 31b of the second rotating body 30b. One end of the first link member 41c is fixed to the protrusion 31c of the third rotating body 30c. One end of each of the first link members 41a to 41c is fixed to the protrusions 31a to 31c of the rotating bodies 30a to 30c, for example, by screws.

[0031] The method of fixing the first link members 41a-41c to the respective protrusions 31a-31c of the rotating bodies 30a-30c may be any method and is not limited to the fastening method described above. The first link members 41a-41c may be fixed to the respective protrusions 31a-31c by, for example, crimping, welding, or adhesive.

[0032] The other end of each of the first link members 41a to 41c is rotatably connected to the other end of each of the first link members 41a to 41c at each of the first rotation pairs 43a to 43c. The other end of the first link member 41a is rotatably connected to one end of the second link member 42a at the first rotation pair 43a. The other end of the first link member 41b is rotatably connected to one end of the second link member 42b at the first rotation pair 43b. The other end of the first link member 41c is rotatably connected to one end of the second link member 42c at the first rotation pair 43c. The shortest distances between each of the first rotation pairs 43a to 43c and the rotation center axis CA1 are equal to each other.

[0033] A through hole (not shown) is formed in the other end of each of the first link members 41a to 41c. A through hole (not shown) is formed in one end of each of the second link members 42a to 42c. A shaft member is passed through both the through hole formed in the other end of each of the first link members 41a to 41c and the through hole formed in one end of each of the second link members 42a to 42c. As a result, one end of each of the second link members 42a to 42c is connected to the other end of each of the first link members 41a to 41c so as to be rotatable around the central axis (first rotation axis RA1) of each shaft member.

[0034] The first link members 41a to 41c have a columnar shape with a bent portion. The lengths of the first link members 41a to 41c are different from one another. The length of the first link member 41a is shorter than the length of the first link member 41b. The length of the first link member 41c is longer than the length of the first link member 41b. In the direction along the rotation center axis CA1, the distance between one end of the first link member 41a and the base-side link hub 10 is longer than the distance between one end of the first link member 41b and the base-side link hub 10. The distance between one end of the first link member 41c and the base-side link hub 10 is shorter than the distance between one end of the first link member 41b and the base-side link hub 10. In the direction along the rotation center axis CA1, the distances between the other ends of the first link members 41a to 41c and the base-side link hub 10 are equal to one another.

[0035] Each of the first link members 41a to 41c has a first portion extending in a direction perpendicular to the surface of the rotors 30a to 30c, a second portion extending obliquely relative to the extending direction of the first portion, and the bent portion that connects the first portion and the second portion. As shown in FIG. 2, the second portion of each of the first link members 41a to 41c is configured to gradually move away from the rotation center axis CA1 as it moves away from the first portion in the direction along the rotation center axis CA1. The one end of each of the first link members 41a to 41c is included in the first portion of each of the first link members 41a to 41c. The other end of each of the first link members 41a to 41c is included in the second portion of each of the first link members 41a to 41c.

[0036] The other end of each of the second link members 42a to 42c is rotatably coupled to a respective protrusion 51a to 51c of the tip side link hub 50 (described later) at each of second revolute pairs 45a to 45c. The other end of the second link member 42a is rotatably coupled to a protrusion 51a of the tip side link hub 50 at the second revolute pair 45a. The other end of the second link member 42b is rotatably coupled to a protrusion 51b of the tip side link hub 50 at the second revolute pair 45b. The other end of the second link member 42c is rotatably coupled to a protrusion 51c of the tip side link hub 50 at the second revolute pair 45c.

[0037] A through hole (not shown) is formed in the other end of each of the second link members 42a to 42c. A through hole (not shown) is formed in each of the protruding portions 51 of the tip-side link hub 50. A shaft member is passed through both the through hole formed in the other end of each of the second link members 42a to 42c and the through hole formed in each of the protruding portions 51 of the tip-side link hub 50. As a result, the other end of each of the second link members 42a to 42c is connected to the respective protruding portion 51 of the tip-side link hub 50 so as to be rotatable around the central axis (second rotation axis RA2) of each shaft member.

[0038] Each of the second rotation axes RA2 extends in a direction different from that of each of the first rotation axes RA1. Each of the first rotation axes RA1 and each of the second rotation axes RA2 extends in a direction toward the rotation central axis CA1.

[0039] The rotation center axis CA1, the first rotation axes RA1, and the second rotation axes RA2 intersect at a single point. In this specification, the point where the rotation center axis CA1, the first rotation axes RA1, and the second rotation axes RA2 intersect is referred to as the spherical link center point P1. The spherical link center point P1 is located on the opposite side of the distal link hub 50 from the proximal link hub 10.

[0040] The structures of the first revolute pairs 43a-43c and the second revolute pairs 45a-45c are not limited to the above structures. For example, in the first revolute pairs 43a-43c, the shaft member may be fixed to either the other end of each of the first link members 41a-41c or one end of each of the second link members 42a-42c, and may be passed through a through hole formed in the other of the other end of each of the first link members 41a-41c or one end of each of the second link members 42a-42c. In the second revolute pairs 45a-45c, the shaft member may be fixed to either the other end of each of the second link members 42a-42c or one of the protrusions 51 of the tip-side link hub 50, and may be passed through a through hole formed in the other of the other end of each of the second link members 42a-42c or one of the protrusions 51 of the tip-side link hub 50.

[0041] The distal link hub 50 is, for example, a plate-shaped member. The distal link hub 50 has a first surface 50a and a second surface 50b located on the opposite side of the first surface 50a. The first surface 50a faces the spherical link center point P1, which will be described later. The second surface 50b faces the proximal link hub 10.

[0042] As shown in FIGS. 1 and 2, the tip-side link hub 50 has protrusions 51a-51c that protrude from the first surface 50a toward the spherical link center point P1 in a direction perpendicular to the first surface 50a. As shown in FIG. 3, in a plan view, each of the protrusions 51a-51c of the tip-side link hub 50 extends outward relative to other portions of the tip-side link hub 50. The center axis CA2 of the tip-side link hub 50 extends in a direction perpendicular to the first surface 50a and passes through the center of each of the protrusions 51a-51c when viewed from the direction perpendicular to the first surface 50a. The shortest distances between each of the second rotation pairs 45a-45c and the center axis CA2 of the tip-side link hub 50 are equal to each other. The center axis CA2 of the tip-side link hub 50 intersects with the rotation center axis CA1, each of the first rotation axes RA1, and each of the second rotation axes RA2 at the spherical link center point P1.

[0043] As shown in FIG. 4, each second rotation axis RA2 is inclined with respect to the central axis CA2 of the tip-side link hub 50. The angle θ1 formed by each second rotation axis RA2 with respect to the central axis CA2 of the tip-side link hub 50 is an acute angle. The angle θ1 formed by each second rotation axis RA2 with respect to the central axis CA2 of the tip-side link hub 50 can be set arbitrarily depending on, for example, the structure of each protrusion 51a to 51c. The smaller the angle θ1, the longer the distance between the spherical link center point P1 and the first surface 50a of the tip-side link hub 50. The distance between the spherical link center point P1 and the first surface 50a of the tip-side link hub 50 can be adjusted depending on the angle θ1 formed by each second rotation axis RA2 with respect to the central axis CA2 of the tip-side link hub 50.

[0044] A working body 100 can be attached to the tip-side link hub 50 to perform work in various devices on which the parallel link mechanism 101 is mounted. The working body 100 is a member that performs any work. The working body 100 is, for example, a non-contact type working body that performs work without contacting a workpiece. The working body 100 has, for example, an optical sensor or a dispenser. The working body 100 may also be a contact type working body that performs work by contacting a workpiece. The working body 100 may have, for example, a tool.

[0045] The tip-side link hub 50 has an attachment portion 52 to which the working body 100 is attached. The attachment portion 52 can adjust the position of the working body 100 so that the point of application P2 of the working body 100 coincides with the spherical link center point P1. The point of application P2 of the working body 100 refers to the center position of an area where the working body 100, positioned at a single coordinate system, works. The point of application P2 of the working body 100 can be located at a position away from the working body 100. If the working body 100 is an optical sensor, the focal point of the optical sensor can be the point of application P2 of the working body 100. In this case, the attachment portion 52 only needs to be arranged so that the focal point of the optical sensor coincides with the spherical link center point P1. If the working body 100 is an optical sensor with an adjustable focal length, the attachment portion 52 only needs to be arranged so that the spherical link center point P1 is located within the adjustment range of the focal length of the optical sensor. If the working body 100 has a dispenser that dispenses a fluid such as grease, the center point of the dispenser's dispensing area can be the point of action P2 of the working body 100. If the working body 100 is a tool, the point of contact of the tool with the workpiece can be the point of action P2 of the working body 100.

[0046] The tip side link hub 50 has a through hole 53 that opens to the first surface 50a, for example. At least a portion of the working body 100 may be passed through the through hole 53. The entire working body 100 may be housed within the through hole 53. The through hole 53 is formed such that, for example, the central axis CA2 of the tip side link hub 50 passes through the through hole 53. The axis of the through hole 53 may coincide with the central axis CA2 of the tip side link hub 50.

[0047] The mounting portion 52 holds the working body 100 so that, for example, a part of the working body 100 protrudes toward the spherical link center point P1 relative to the first surface 50a of the tip-side link hub 50, another part of the working body 100 is positioned within the through hole 53 of the tip-side link hub 50, and the remaining part of the working body 100 protrudes toward the base-side link hub 10 relative to the second surface 50b of the tip-side link hub 50.

[0048] The mounting portion 52 has, for example, a third portion 52a disposed radially outward of the through-hole 53 relative to the central axis CA2 of the tip side link hub 50, and a fourth portion 52b extending from the third portion 52a into the through-hole 53. The third portion 52a is fixed, for example, to the second surface 50b of the tip side link hub 50. The working body 100 is fixed to the fourth portion 52b. Any fixing method may be used to fix the third portion 52a to the tip side link hub 50 and to fix the working body 100 to the fourth portion 52b. The third portion 52a is fixed to the tip side link hub 50 by, for example, fastening. The working body 100 is fixed to the fourth portion 52b by, for example, fastening, crimping, welding, or adhesive.

[0049] The attachment portion 52 may detachably hold the working body 100 relative to the tip side link hub 50. The attachment portion 52 may be configured as a tool changer or a tool holder. Instead of the through hole 53, the tip side link hub 50 may be provided with a recess that opens to the first surface 50a. <Operation of the parallel link mechanism> In the parallel link mechanism 101, by rotating the three rotating bodies 30a to 30c in the same direction and by the same angle around the rotation center axis CA1, the tip side link hub 50 can be rotated around the rotation center axis CA1 while maintaining the attitude of the tip side link hub 50 relative to the base side link hub 10.

[0050] By varying at least one of the rotation direction and rotation angle of each of the three rotating bodies 30a to 30c, the posture of the distal link hub 50 relative to the proximal link hub 10 can be changed as desired. From a different perspective, by varying at least one of the rotation direction and rotation angle of each of the three rotating bodies 30a to 30c, the posture of the distal link hub 50 relative to the proximal link hub 10 can be changed as desired.

[0051] By controlling at least one of the rotation direction and rotation angle of each of the three rotating bodies 30a to 30c, the bending angle and swivel angle that represent the attitude of the tip side link hub 50 as viewed from the spherical link center point P1 can be controlled.

[0052] The bending angle is the angle formed at the spherical link center point P1 between the central axis CA2 of the tip side link hub 50 and the rotation central axis CA1 of each rotating body 30a to 30c. The swivel angle is the angle formed between the straight line obtained by projecting the central axis CA2 of the tip side link hub 50 onto an imaginary plane perpendicular to the rotation central axis CA1 at the spherical link center point P1, and the X-axis set on the imaginary plane with the spherical link center point P1 as its origin.

[0053] In the parallel link mechanism 101, the attitude of the tip side link hub 50 relative to the base side link hub 10 has three degrees of rotational freedom: one degree of rotational freedom around the rotation center axis CA1 and two degrees of rotational freedom around the spherical link center point P1.

[0054] In the parallel link mechanism 101, any one of the rotating bodies 30a to 30c may be fixed to the base-side link hub 10. In this case, by controlling at least one of the rotational direction and rotational angle of each of the remaining two rotating bodies, the attitude of the tip-side link hub 50 relative to the base-side link hub 10 has two rotational degrees of freedom. When using one fixed rotating body, that one rotating body may be omitted, and the first link member of one link mechanism to be connected to that one rotating body may be fixed to the base-side link hub 10.

[0055] <effect> In the parallel link mechanism 101, the first rotation axis RA1 of the first rotation pairs 43a to 43c and the second rotation axis RA2 of the second rotation pairs 45a to 45c of each of the three link mechanisms 40a to 40c intersect with the rotation center axis CA1 of the three rotating bodies 30a to 30c at the spherical link center point P1. Therefore, the attitude of the tip-side link hub 50 relative to the base-side link hub 10 has three rotational degrees of freedom. Therefore, the movable range of the tip-side link hub 50 of the parallel link mechanism 101 is larger than that of a parallel link mechanism that has two rotational degrees of freedom.

[0056] Furthermore, in the parallel link mechanism 101, the attachment portion 52 allows the point of application P2 of the working body 100 to coincide with the spherical link center point P1, and the posture of the working body 100 can be changed around the point of application P2. In this way, it is easy to imagine changes in the posture of the working body 100, making it easier to adjust the movement of the working body 100. In particular, with non-contact working bodies, adjustment of the movement tends to be difficult, but the parallel link mechanism 101 makes it easier to adjust the movement of the working body 100 even if the working body 100 is a non-contact type.

[0057] Furthermore, the parallel link mechanism 101 makes it possible to easily change the posture of the working body 100 relative to one point of application P2. For example, if the working body 100 is an optical sensor, the posture of the working body 100 relative to the inspection area can be easily changed by setting the spherical link center point P1 of the parallel link mechanism 101 in the inspection area of ​​the mechanical part. As a result, the use of the parallel link mechanism 101 makes it easy to perform the above-mentioned inspection work.

[0058] <Modification> In the parallel link mechanism 101, the number of rotating bodies may be three or more. The number of link mechanisms may be three or more. Preferably, the number of rotating bodies is equal to the number of link mechanisms. The parallel link mechanism 101 may include a working body 100.

[0059] (Embodiment 2) 5 to 7, a parallel link mechanism 102 according to the second embodiment will be described. Unless otherwise specified, the parallel link mechanism 102 according to the second embodiment has the same configuration and effects as the parallel link mechanism 101 according to the first embodiment. Therefore, the same components as those in the parallel link mechanism 101 are denoted by the same reference numerals, and description thereof will not be repeated.

[0060] Fig. 5 is a perspective view illustrating a parallel link mechanism 102 according to embodiment 2. Fig. 6 is a side view of the parallel link mechanism 102 according to embodiment 2. Fig. 3 is a top view of the parallel link mechanism shown in Fig. 1. Fig. 7 is a cross-sectional view illustrating a rotating body, a rotation transmission member, and a connecting member of the parallel link mechanism according to embodiment 2.

[0061] 5 shows a state in which the central axis CA2 of the distal link hub 50 of the parallel link mechanism 102 is inclined with respect to the central rotation axis CA1 of the three rotating bodies 30a to 30c. Fig. 6 shows a state in which the central axis CA2 of the distal link hub 50 of the parallel link mechanism 102 overlaps with the central rotation axis CA1 of the three rotating bodies 30a to 30c.

[0062] As shown in FIGS. 5 to 7, the parallel link mechanism 102 differs from the parallel link mechanism 101 in that it further includes three rotation transmission members 60a to 60c and three connecting members 70a to 70c (see FIG. 7).

[0063] The three rotation transmission members 60a to 60c are a first rotation transmission member 60a, a second rotation transmission member 60b, and a third rotation transmission member 60c. Each of the first rotation transmission member 60a, the second rotation transmission member 60b, and the third rotation transmission member 60c is rotatable around a rotation central axis CA1. The first rotation transmission member 60a, the second rotation transmission member 60b, and the third rotation transmission member 60c are stacked in a direction along the rotation central axis CA1 so that their respective rotation central axes CA1 coincide.

[0064] The first rotation transmission member 60a, the second rotation transmission member 60b, and the third rotation transmission member 60c are each, for example, a plate-shaped member. Each of the first rotation transmission member 60a, the second rotation transmission member 60b, and the third rotation transmission member 60c has a through-hole. The through-holes of the first rotation transmission member 60a, the second rotation transmission member 60b, and the third rotation transmission member 60c overlap with each other in the direction along the rotation central axis CA1 and also overlap with the through-holes of the first rotating body 30a, the second rotating body 30b, and the third rotating body 30c.

[0065] The diameter of the through hole of the second rotation transmission member 60b is larger than the diameter of the through hole of the first rotation transmission member 60a, for example. The diameter of the through hole of the third rotation transmission member 60c is larger than the diameter of the through hole of the second rotation transmission member 60b, for example.

[0066] The diameter of the through hole of the first rotation transmission member 60a is equal to the diameter of the through hole of the first rotating body 30a, for example. The diameter of the through hole of the second rotation transmission member 60b is equal to the diameter of the through hole of the second rotating body 30b, for example. The diameter of the through hole of the third rotation transmission member 60c is equal to the diameter of the through hole of the third rotating body 30c, for example.

[0067] The first rotation transmission member 60a, the second rotation transmission member 60b, the third rotation transmission member 60c, the third rotating body 30c, the second rotating body 30b, and the first rotating body 30a are arranged in the above-described order from the side of the base-end link hub 10. The shaft member 20 is passed through each of the through holes of the first rotation transmission member 60a, the second rotation transmission member 60b, the third rotation transmission member 60c, the third rotating body 30c, the second rotating body 30b, and the first rotating body 30a.

[0068] 7, the three connecting members 70a to 70c are a first connecting member 70a, a second connecting member 70b, and a third connecting member 70c. The first connecting member 70a connects the first rotation transmission member 60a and the first rotating body 30a. The second connecting member 70b connects the second rotation transmission member 60b and the second rotating body 30b. The third connecting member 70c connects the third rotation transmission member 60c and the third rotating body 30c.

[0069] The first rotation transmission member 60a, the first rotating body 30a, and the first connecting member 70a are rotatable as a unit around the rotation center axis. The second rotation transmission member 60b, the second rotating body 30b, and the second connecting member 70b are rotatable as a unit around the rotation center axis. The third rotation transmission member 60c, the third rotating body 30c, and the third connecting member 70c are rotatable as a unit around the rotation center axis. The unit consisting of the first rotation transmission member 60a, the first rotating body 30a, and the first connecting member 70a, the unit consisting of the second rotation transmission member 60b, the second rotating body 30b, and the second connecting member 70b, and the unit consisting of the third rotation transmission member 60c, the third rotating body 30c, and the third connecting member 70c are rotatable independently of each other.

[0070] The first connecting member 70a is connected to, for example, the inner circumferential surfaces of the through holes of the first rotation transmission member 60a and the first rotating body 30a. The first connecting member 70a is passed through the inside of the through holes of the second rotation transmission member 60b, the third rotation transmission member 60c, the third rotating body 30c, and the second rotating body 30b.

[0071] The second connecting member 70b is connected to, for example, the inner circumferential surfaces of the through holes of the second rotation transmission member 60b and the second rotor 30b. The second connecting member 70b is passed through the through holes of the third rotation transmission member 60c and the third rotor 30c. The second connecting member 70b is disposed radially outward of the first connecting member 70a relative to the rotation center axis CA1.

[0072] The third connecting member 70c is connected to, for example, the inner circumferential surfaces of the through holes of the third rotation transmission member 60c and the third rotor 30c. The third connecting member 70c is disposed radially outward of the second connecting member 70b with respect to the rotation center axis CA1.

[0073] Each of the first connecting member 70a, the second connecting member 70b, and the third connecting member 70c is, for example, a tubular member. Each of the first connecting member 70a, the second connecting member 70b, and the third connecting member 70c is, for example, a cylindrical member.

[0074] The first connecting member 70a is fitted into the through-holes of the first rotation transmission member 60a and the first rotating body 30a, for example. The second connecting member 70b is fitted into the through-holes of the second rotation transmission member 60b and the second rotating body 30b, for example. The third connecting member 70c is fitted into the through-holes of the third rotation transmission member 60c and the third rotating body 30c, for example.

[0075] The second connecting member 70b is passed through the inside of the third connecting member 70c. The first connecting member 70a is passed through the inside of the second connecting member 70b and the third connecting member 70c. The shaft member 20 is passed through the inside of the first connecting member 70a, the second connecting member 70b, and the third connecting member 70c. The shaft member 20, the first connecting member 70a, the second connecting member 70b, and the third connecting member 70c are arranged side by side from the inside in the radial direction with respect to the rotation central axis CA1.

[0076] In the direction along the rotation center axis CA1, the length of the first connecting member 70a is shorter than the length of the male thread portion of the shaft member 20 and longer than the length of the second connecting member 70b. In the direction along the rotation center axis CA1, the length of the second connecting member 70b is longer than the length of the third connecting member 70c.

[0077] As shown in FIG. 7 , a bearing 80 is disposed between the shaft member 20 and the first connecting member 70a in the through-holes of the first rotating body 30a and the first rotation transmission member 60a. A bearing 80 is disposed between the first connecting member 70a and the second connecting member 70b in the through-holes of the second rotating body 30b and the second rotation transmission member 60b. A bearing 80 is disposed between the second connecting member 70b and the third connecting member 70c in the through-holes of the third rotating body 30c and the third rotation transmission member 60c. Each bearing 80 reduces friction between the shaft member 20 and each of the first rotation transmission member 60a, the second rotation transmission member 60b, the third rotation transmission member 60c, the first rotating body 30a, the second rotating body 30b, and the third rotating body 30c. The bearings are, for example, rolling bearings.

[0078] As shown in FIG. 7 , the relative positions of the base-end link hub 10, the first rotation transmission member 60a, the second rotation transmission member 60b, the third rotation transmission member 60c, the first rotating body 30a, the second rotating body 30b, and the third rotating body 30c in the direction along the rotation central axis CA1 are restricted by, for example, a plurality of positioning members 81. At least one positioning member 81 is disposed, for example, between the first rotating body 30a and the inner ring of a bearing 80 disposed in the through hole of the second rotating body 30b. At least one positioning member 81 is disposed, for example, between the second rotating body 30b and the inner ring of a bearing 80 disposed in the through hole of the third rotating body 30c. At least one positioning member 81 is disposed, for example, between the inner rings of the bearings 80 disposed in the through holes of the third rotating body 30c and the third rotation transmission member 60c. At least one positioning member 81 is disposed, for example, between the inner ring of the bearing 80 disposed in the through hole of the third rotation transmission member 60c and the second rotation transmission member 60b. At least one positioning member 81 is disposed, for example, between the inner ring of the bearing 80 disposed in the through hole of the second rotation transmission member 60b and the first rotation transmission member 60a. At least one positioning member 81 is disposed, for example, between the inner ring of the bearing 80 disposed in the through hole of the first rotation transmission member 60a and the base-end link hub 10.

[0079] <Modification> In the parallel link mechanism 102, each of the first connecting member 70a, the second connecting member 70b, and the third connecting member 70c may be a rod-shaped or plate-shaped member. In the parallel link mechanism 102, the number of rotating bodies may be three or more. The number of link mechanisms may be three or more. Preferably, the number of rotating bodies is equal to the number of link mechanisms. The parallel link mechanism 102 may include a working body 100.

[0080] (Embodiment 3) <Configuration of link actuator> A link actuation device 201 according to the third embodiment will be described with reference to Fig. 8. Fig. 8 is a partially enlarged cross-sectional view for explaining the link actuation device 201 according to the third embodiment. As shown in Fig. 8, the link actuation device 201 mainly includes a parallel link mechanism and three attitude control drive sources 210a to 210c for driving the parallel link mechanism. Note that the number of attitude control drive sources in the link actuation device 201 may be two or more. The number of attitude control drive sources may be less than the number of link mechanisms.

[0081] The parallel link mechanism provided in the link actuation device 201 shown in Fig. 8 has a configuration similar to that of the parallel link mechanism 101 shown in Figs. 1 to 4. The parallel link mechanism shown in Fig. 8 has a plurality of bearings 80 arranged in the through holes of each of the three rotating bodies 30a to 30c. Note that part of the parallel link mechanism is not shown in Fig. 8.

[0082] Each of the rotating bodies 30a to 30c has a first inner circumferential surface 34 and a second inner circumferential surface 35. The first inner circumferential surface 34 and the second inner circumferential surface 35 are the inner circumferential surfaces of through holes provided in each of the rotating bodies 30a to 30c. The first inner circumferential surface 34 and the second inner circumferential surface 35 extend in the circumferential direction about the rotation center axis CA1. The first inner circumferential surface 34 is connected to the outer ring of the bearing 80. The second inner circumferential surface 35 is disposed closer to the base-end link hub 10 than the first inner circumferential surface 34 in the direction along the rotation center axis CA1. The second inner circumferential surface 35 is disposed outward from the first inner circumferential surface 34 in the radial direction about the rotation center axis CA1. The inner diameter of the second inner circumferential surface 35 is larger than the inner diameter of the first inner circumferential surface 34.

[0083] Each of the plurality of bearings 80 is disposed between the first inner peripheral surface 34 of each of the rotors 30a to 30c and the outer peripheral surface of the shaft member 20 in the radial direction relative to the central axis of rotation CA1. Each of the plurality of bearings 80 is disposed, in the direction along the central axis of rotation CA1, between two adjacent yokes of yoke portions 211a to 211c (described later) and between the yoke portion 211a and the positioning member 32. Each of the plurality of bearings 80 reduces friction between the shaft member 20 and the first rotor 30a, the second rotor 30b, or the third rotor 30c.

[0084] Each of the attitude control driving sources 210a-210c is configured as an outer rotor motor. Each of the attitude control driving sources 210a-210c has yoke portions 211a-211c, multiple teeth portions 212a-212c, magnets 213a-213c, stator coils 214a-214c, and a control unit (not shown). The control unit controls the value of the current flowing through each of the stator coils 214a-214c.

[0085] The magnets 213a to 213c are fixed to the second inner circumferential surface 35 of each of the rotors 30a to 30c. The magnets 213a to 213c are provided, for example, in an annular shape. The inner circumferential surface of each of the magnets 213a to 213c is disposed outward of the first inner circumferential surface 34 in the radial direction relative to the rotation central axis CA1.

[0086] Each of the yoke portions 211a to 211c is disposed, in the radial direction relative to the rotation central axis CA1, between the outer peripheral surface of the shaft member 20 and the magnets 213a to 213c fixed to the second inner peripheral surfaces 35 of the rotors 30a to 30c. Each of the yoke portions 211a to 211c is disposed, in the direction along the rotation central axis CA1, between two adjacent bearings 80 or between a bearing 80 and the base-side link hub 10.

[0087] Each of the plurality of teeth 212a to 212c is disposed between each of the yoke portions 211a to 211c and the magnets 213a to 213c in the radial direction relative to the central axis of rotation CA1. Each of the plurality of teeth 212a to 212c extends radially outward beyond the first inner circumferential surfaces 34 of the rotors 30a to 30c.

[0088] The plurality of teeth 212a are arranged at intervals from one another in the circumferential direction relative to the rotation center axis CA1. The stator coil 214a is wound around each of the plurality of teeth 212a. The stator coil 214a is disposed to face the magnet 213a in the radial direction relative to the rotation center axis CA1. At least a portion of the stator coil 214a is disposed radially outward from the first inner circumferential surface 34.

[0089] The plurality of teeth 212b and the plurality of teeth 212b each have the same configuration as the plurality of teeth 212a.

[0090] 8, attitude control drive sources 210a-210c constitute outer rotor motors. When the control unit supplies current to each of stator coils 214a-214c, yoke portions 211a-211c act as electromagnets, causing magnets 213a-213c and rotors 30a-30c to rotate integrally. When at least one of rotors 30a-30c rotates, the attitude of distal link hub 50 changes.

[0091] According to the link actuator 201, the attitude control drive sources 210a to 210c individually control the link mechanisms, thereby enabling the distal end link hub 50 to move over a wide range and precisely.

[0092] (Fourth embodiment) <Configuration of link actuator> 9 and 10, a link actuation device 202 according to the fourth embodiment will be described. Unless otherwise specified, the parallel link mechanism 202 according to the fourth embodiment has the same configuration and effects as the link actuation device 201 according to the third embodiment.

[0093] Fig. 9 is a perspective view illustrating a link actuation device 202 according to the fourth embodiment. Fig. 10 is a side view illustrating the link actuation device 202 according to the fourth embodiment. As shown in Figs. 9 and 10, the link actuation device 202 mainly includes a parallel link mechanism and attitude control drive sources 220a to 220c for driving the parallel link mechanism. Note that Fig. 10 does not show the attitude control drive sources 220b and 220c.

[0094] The parallel link mechanism provided in the link actuator 202 shown in FIGS. 9 and 10 has a configuration similar to that of the parallel link mechanism 102 shown in FIGS. 5 to 7, for example.

[0095] Each of the attitude control driving sources 220a to 220c includes a motor 221a to 221c, a fixed portion 222a to 222c, and a first transmission portion 223a to 223c.

[0096] The motors 221a to 221c are, for example, electric motors. The motors 221a to 221c have rotating shafts. The fixing portions 222a to 222c fix the motors 221a to 221c to the base-end link hub 10. The first transmission portions 223a to 223c are fixed to the rotating shafts of the motors 221a to 221c. The outer peripheral surfaces of the first transmission portions 223a to 223c are connected to the outer peripheral surfaces of the rotation transmission members 60a to 60c, respectively. The first transmission portions 223a to 223c are arranged to transmit the power of the motors 221a to 221c to the rotation transmission members 60a to 60c. The rotation transmission members 60a to 60c and the first transmission portions 223a to 223c each have, for example, gear portions arranged to mesh with each other.

[0097] In the link actuator 202 as well, the number of attitude control drive sources may be two or more. The number of attitude control drive sources may be less than the number of link mechanisms.

[0098] (Embodiment 5) <Configuration of link actuator> A link actuation device 203 according to the fifth embodiment will be described with reference to Fig. 11. Unless otherwise specified, the parallel link mechanism 203 according to the fifth embodiment has the same configuration and effect as the link actuation device 202 according to the fourth embodiment described above. Therefore, the same components as those in the link actuation device 202 described above are denoted by the same reference numerals, and description thereof will not be repeated.

[0099] Link actuation device 203 differs from link actuation device 202 in that each of the plurality of attitude control drive sources further includes a second transmission unit. Note that attitude control drive sources 220b and 220c are not shown in Figure 11.

[0100] As shown in FIG. 11, the attitude control driving source 220a further includes a second transmission part 224a. The second transmission part 224a is wound around the outer circumferential surfaces of the first rotation transmission member 60a and the first transmission part 223a of the attitude control driving source 220a. The second transmission part 224a is, for example, a belt. The second transmission part 224a is, for example, a timing belt. When the second transmission part 224a is a timing belt, the operating noise of the link actuator 203 can be reduced compared to the operating noise of the link actuator 202. The first transmission part 223a and the second transmission part 224a are arranged to transmit the power of the motors 221a to 221c to the rotation transmission members 60a to 60c. Preferably, the outer diameter of the first transmission part 223a is smaller than the outer diameter of the first rotation transmission member 60a. In this way, the link actuator 203 can be made smaller than when the outer diameter of the first transmission part 223a is equal to or larger than the outer diameter of the first rotation transmission member 60a, and it becomes easier to operate the tip side link hub 50 precisely.

[0101] The attitude control drive sources 220b and 220c may have the same configuration as the attitude control drive source 220a.

[0102] In the link actuator 203 as well, the number of attitude control drive sources may be two or more. The number of attitude control drive sources may be less than the number of link mechanisms.

[0103] <Modification of working body> As described above, the type of working body is not particularly limited in the parallel link mechanisms 101 and 102 according to the first and second embodiments and the link actuation devices 201 to 203 according to the third to fifth embodiments. Figures 12 to 14 show an example of a link actuation device equipped with a dispenser that dispenses a fluid such as grease as the working body. Note that tubes and the like for supplying fluid to the dispenser are not shown in Figures 12 to 14.

[0104] In the link actuator 204 shown in FIGS. 12 to 14, a working body 300 is mounted on the distal link hub 50. The working body 300 has, for example, a first pipe 300a and a second pipe 300b. The first pipe 300a is connected to the mounting portion 52. The first pipe 300a extends, for example, parallel to the central axis CA2 of the distal link hub 50. The second pipe 300b has one end communicating with the first pipe 300a and the other end forming an outlet. The extending direction of the central axis of the second pipe 300b intersects with the central axis CA2 of the distal link hub 50. The angle formed between the central axis of the second pipe 300b and the central axis of the first pipe 300a is, for example, an obtuse angle.

[0105] The point of application P2 of the working body 300 is located on the central axis of the second pipe portion 300b. In this case, the direction in which the fluid is discharged from the working body 300 intersects with the central axis CA2 of the distal link hub 50.

[0106] The mounting portion 52 is capable of adjusting the position of the working body 300 relative to the distal link hub 50 so that the point of application P2 of the working body 300 coincides with the spherical link center point P1 of the link actuator 204.

[0107] According to the link actuation device 204, by setting the spherical link center point P1 at a fluid supply point in the mechanical component, the posture of the working body 300 can be easily changed relative to the supply point.

[0108] The parallel link mechanism of the link actuator 204 may have a configuration similar to that of the parallel link mechanism 101, except that the working body 300 can be mounted on the tip-end link hub 50. The link actuator 204 may have a configuration similar to that of the link actuators 201 and 203, except that the working body 300 can be mounted on the tip-end link hub 50.

[0109] Various aspects of the present disclosure are summarized below as appendices. [Appendix 1] A parallel link mechanism on which a working body is mounted, a base end link hub; A shaft member; Three or more rotating bodies; Three or more linkages; a tip side link hub, the three or more rotating bodies are connected to the base-end link hub by the shaft member so as to be rotatable around the rotation central axis, with the rotating bodies being arranged side by side so that their rotation central axes coincide with each other; Each of the three or more link mechanisms includes a first link member and a second link member, the first link member of each of the three or more link mechanisms is fixed to one of the three or more rotating bodies; In each of the three or more link mechanisms, the second link member is rotatably connected to the first link member at a first rotation pair and is rotatably connected to the tip-side link hub at a second rotation pair, a first rotation axis of the first rotation pair and a second rotation axis of the second rotation pair of each of the three or more link mechanisms intersect with the rotation center axis of the three or more rotating bodies at a spherical link center point, the tip-side link hub includes a mounting portion to which the working body is attached, a parallel link mechanism, wherein the attachment portion is capable of adjusting the position of the working body so that the point of application of the working body coincides with the center point of the spherical link; [Appendix 2] The working body is attached to the attachment portion, 2. The parallel link mechanism according to claim 1, wherein the point of action of the working body coincides with the center point of the spherical link. [Appendix 3] the tip side link hub has a first surface facing the spherical link center point, The tip-side link hub has a through hole that opens to the first surface, 3. The parallel link mechanism according to claim 1, wherein the attachment portion is configured to hold the working body, at least a portion of which is passed through the through hole. [Appendix 4] a base end link hub; A shaft member; Three or more rotating bodies; Three or more linkages; a tip side link hub; a working body attached to the tip side link hub, the three or more rotating bodies are connected to the base-end link hub by the shaft member so as to be rotatable around the rotation central axis, with the rotating bodies being arranged side by side so that their rotation central axes coincide with each other; Each of the three or more link mechanisms includes a first link member and a second link member, the first link member of each of the three or more link mechanisms is fixed to one of the three or more rotating bodies; In each of the three or more link mechanisms, the second link member is rotatably connected to the first link member at a first rotation pair and is rotatably connected to the tip-side link hub at a second rotation pair, a first rotation axis of the first rotation pair and a second rotation axis of the second rotation pair of each of the three or more link mechanisms intersect with the rotation center axis of the three or more rotating bodies at a spherical link center point, A parallel link mechanism in which the point of action of the working body coincides with the center point of the spherical link. [Appendix 5] the tip side link hub has a first surface facing the spherical link center point, The tip-side link hub has a through hole that opens to the first surface, 5. The parallel link mechanism according to claim 4, wherein at least a portion of the working body is passed through the through hole. [Appendix 6] 6. The parallel link mechanism according to any one of appendixes 1 to 5, wherein at least a portion of the second rotation pair of each of the three or more link mechanisms is disposed closer to the spherical link center point than the first surface in a direction perpendicular to the first surface. [Appendix 7] the working body is an optical sensor, 7. The parallel link mechanism according to any one of claims 1 to 6, wherein a focal point of the optical sensor serving as the point of action coincides with a center point of the spherical link. [Appendix 8] the three or more rotating bodies include a first rotating body and a second rotating body, a first rotation transmission member disposed between the first rotor and the base-end link hub in a direction along the rotation central axis; a first connecting member that connects the first rotor and the first rotation transmission member; a second rotation transmission member disposed between the second rotor and the base-end link hub in a direction along the rotation central axis; a second connecting member that connects the second rotor and the second rotation transmission member, the first rotating body, the second rotating body, the second rotation transmission member, and the first rotation transmission member are arranged in sequence in a direction along the rotation central axis, 8. The parallel link mechanism according to any one of claims 1 to 7, wherein the shaft member, the first connecting member, and the second connecting member are arranged in order in a radial direction relative to the central axis of rotation. [Appendix 9] A parallel link mechanism according to any one of appendices 1 to 8; a first drive source that rotates a first rotating body among the three or more rotating bodies around the rotation center axis; a second drive source that rotates a second rotating body among the three or more rotating bodies around the central rotation axis. [Appendix 10] a parallel link mechanism according to appendix 8; a first drive source that rotates the first rotor around the rotation center axis via the first rotation transmission member; a second drive source that rotates the second rotating body around the rotation center axis via the second rotation transmission member.

[0110] Although the embodiments of the present disclosure have been described above, the above-described embodiments can be modified in various ways. Furthermore, the scope of the present disclosure is not limited to the above-described embodiments. The scope of the present disclosure is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0111] 10 base end side link hub, 20 shaft member, 21 bolt, 22 nut, 30a to 30c rotating body, 31a to 31c protrusion, 32 positioning member, 34 first inner circumferential surface, 35 second inner circumferential surface, 40a to 40c link mechanism, 41a to 41c first link member, 42a to 42c second link member, 43a to 43c first rotation pair, 45a to 45c second rotation pair, 50 tip end side link hub, 50a first surface, 50b second surface, 51a to 51c protrusion, 52 mounting portion, 52a third portion, 52b fourth portion, 53 through hole, 60a to 60c rotation transmission member, 70a to 70c connecting member, 80 bearing, 81 positioning member, 100 working body, 101, 102 Parallel link mechanism, 201, 202, 203 link actuators, 210a to 210c attitude control drive source, 211a to 211c yoke portion, 212a to 212c teeth portion, 213a to 213c magnet, 214a to 214c stator coil, 220a to 220c attitude control drive source, 221a to 221c motor, 222a to 222c fixed portion, 223a to 223c first transmission portion, 224a second transmission portion, 300 working body, 300a first pipe portion, 300b second pipe portion, CA1 rotation central axis, CA2 central axis, P1 spherical link central point, P2 point of action, RA1 first rotation axis, RA2 second rotation axis.

Claims

1. A parallel link mechanism on which a working body is mounted, a base end link hub; A shaft member; Three or more rotating bodies; three or more link mechanisms; a tip side link hub, the three or more rotating bodies are connected to the base-end link hub by the shaft member so as to be rotatable around the rotation central axis, with the rotating bodies being arranged side by side so that their rotation central axes coincide with each other; each of the three or more link mechanisms includes a first link member and a second link member; the first link member of each of the three or more link mechanisms is fixed to one of the three or more rotating bodies, In each of the three or more link mechanisms, the second link member is rotatably connected to the first link member at a first revolute pair and is rotatably connected to the tip-side link hub at a second revolute pair, a first rotation axis of the first rotation pair and a second rotation axis of the second rotation pair of each of the three or more link mechanisms intersect with the rotation center axis of the three or more rotating bodies at a spherical link center point, the tip-side link hub includes a mounting portion to which the working body is attached, a parallel link mechanism, wherein the attachment portion is capable of adjusting the position of the working body so that the point of application of the working body coincides with the center point of the spherical link;

2. The working body is attached to the attachment portion, The parallel link mechanism according to claim 1 , wherein the point of application of the working body coincides with the center point of the spherical link.

3. the tip side link hub has a first surface facing the spherical link center point, The tip-side link hub has a through-hole or a recess that opens to the first surface, The parallel link mechanism according to claim 1 , wherein the attachment portion is provided to hold the working body, at least a portion of which is passed through the through hole.

4. a base end link hub; A shaft member; Three or more rotating bodies; three or more link mechanisms; A tip side link hub; a working body attached to the tip side link hub, the three or more rotating bodies are connected to the base-end link hub by the shaft member so as to be rotatable around the rotation central axis, with the rotating bodies being arranged side by side so that their rotation central axes coincide with each other; each of the three or more link mechanisms includes a first link member and a second link member; the first link member of each of the three or more link mechanisms is fixed to one of the three or more rotating bodies, In each of the three or more link mechanisms, the second link member is rotatably connected to the first link member at a first revolute pair and is rotatably connected to the tip-side link hub at a second revolute pair, a first rotation axis of the first rotation pair and a second rotation axis of the second rotation pair of each of the three or more link mechanisms intersect with the rotation center axis of the three or more rotating bodies at a spherical link center point, A parallel link mechanism in which the point of action of the working body coincides with the center point of the spherical link.

5. the tip side link hub has a first surface facing the spherical link center point, The tip-side link hub has a through-hole or a recess that opens to the first surface, The parallel link mechanism according to claim 4 , wherein at least a portion of the working body is passed through the through hole.

6. 6. The parallel link mechanism according to claim 3, wherein at least a part of the second rotational pair of each of the three or more link mechanisms is disposed closer to the spherical link center point than the first surface in a direction perpendicular to the first surface.

7. the working body is an optical sensor, 5. The parallel link mechanism according to claim 1, wherein a focal point of the optical sensor serving as the point of action can coincide with a center point of the spherical link.

8. the three or more rotating bodies include a first rotating body and a second rotating body, a first rotation transmission member disposed between the first rotor and the base-end link hub in a direction along the rotation central axis; a first connecting member that connects the first rotor and the first rotation transmission member; a second rotation transmission member disposed between the second rotor and the base-end link hub in a direction along the rotation central axis; a second connecting member that connects the second rotor and the second rotation transmission member, the first rotating body, the second rotating body, the second rotation transmission member, and the first rotation transmission member are arranged in order in a direction along the rotation central axis, The parallel link mechanism according to claim 1 or 4, wherein the shaft member, the first connecting member, and the second connecting member are arranged in order in a radial direction relative to the central axis of rotation.

9. The parallel link mechanism according to claim 1 or 4; a first drive source that rotates a first rotating body among the three or more rotating bodies around the rotation center axis; a second drive source that rotates a second rotating body among the three or more rotating bodies about the central rotation axis.

10. The parallel link mechanism according to claim 8; a first drive source that rotates the first rotor around the rotation center axis via the first rotation transmission member; a second drive source that rotates the second rotating body about the rotation center axis via the second rotation transmission member.

Images