JP7417917B2 - Parallel link mechanism and link actuator - Google Patents

Description

The present invention relates to a parallel link mechanism and a link actuating device.

Parallel link mechanisms used in various devices such as medical equipment and industrial equipment are conventionally known. Such a parallel link mechanism is disclosed, for example, in Japanese Patent Application Publication No. 2000-94245 (Patent Document 1) and US Pat. No. 5,893,296 (Patent Document 2).

Japanese Patent Application Publication No. 2000-94245 US Patent No. 5,893,296

The parallel link mechanism disclosed in Japanese Unexamined Patent Publication No. 2000-94245 has a relatively simple configuration, but the operating angle of each link is small. Therefore, if the operating range of the traveling plate is set to be large, the length of the link becomes long, which increases the dimensions of the entire mechanism, leading to a problem in that the device becomes larger.

The parallel link mechanism disclosed in U.S. Patent No. 5,893,296 connects a proximal link hub as a proximal member and a distal link hub as a distal member into three or more sets of four-bar chains. They are connected via a mechanism. In the parallel link mechanism disclosed in US Pat. No. 5,893,296, the attitude of the distal end member relative to the proximal end member can be changed. The parallel link mechanism of US Pat. No. 5,893,296 is compact, yet capable of high speed, high precision, and wide operating range operation.

However, in the parallel link mechanism of U.S. Pat. No. 5,893,296, the radius of rotation of the moving path of the tip member changes depending on the position of the tip member, and the position of the rotation center of the rotational movement of the tip member changes. Cannot be fixed. That is, when viewed from the proximal end member, the distal end member cannot move on a spherical surface having a constant radius from a fixed center of rotation, so there is a problem in that it is difficult to visualize the operation of the distal end member. Furthermore, since the distal end member operates with two rotational degrees of freedom relative to the proximal end member, there is also the problem that the radius of rotation of the distal end member cannot be controlled independently of the rotational movement of the distal end member. Moreover, when an end effector, which is a working body, is mounted on the tip member and operated, the moment of inertia increases and vibration increases, which may reduce the life of the parallel link mechanism.

The present invention has been made in view of the above problems. The purpose of this is to enable the tip member to move on a spherical surface having a constant radius from a fixed center of rotation, to control the rotation radius of the tip member independently of the rotational movement, and to further suppress vibrations. It is an object of the present invention to provide a parallel link mechanism and a link actuating device that can improve the service life.

A parallel link mechanism according to the present disclosure includes a proximal member and three or more link mechanisms. The three or more linkages are configured to connect the proximal member and the distal member. Three or more link mechanisms can change the attitude of the distal end member relative to the proximal end member. Each of the three or more link mechanisms includes first to fourth link members. The first link member is rotatably connected to the proximal member at the first rotating pair. The second link member is rotatably connected to the first link member at a second rotating pair. The third link member is rotatably connected to the second link member at a third rotating pair. The fourth link member is rotatably connected to the third link member at a fourth rotating pair. The fourth link member is further configured to be rotatably connected to the tip member at the fifth rotating pair. In a link mechanism of three or more, the first central axis of the first rotating pair and the second central axis of the second rotating pair intersect at the center point of the spherical link. The fifth rotating pairs of the three or more link mechanisms are independently arranged at different positions.

A link actuating device according to the present disclosure includes the above-described parallel link mechanism and a posture control drive source. The posture control drive source is installed in at least three link mechanisms among the three or more link mechanisms, and arbitrarily changes the posture of the distal end member with respect to the proximal end member.

According to the above, the tip member can move on a spherical surface having a constant radius from a fixed rotation center, and the rotation radius of the tip member can be controlled independently of the rotational movement, and further vibration can be suppressed. A parallel link mechanism and a link actuating device that can be controlled and have an improved lifespan are obtained.

1 is a schematic perspective view showing the configuration of a parallel link mechanism according to Embodiment 1. FIG. FIG. 2 is a schematic front view of the parallel link mechanism shown in FIG. 1. FIG. 3 is a schematic cross-sectional view taken along line III-III in FIG. 2. FIG. 4 is a schematic cross-sectional view taken along line IV-IV in FIG. 3. FIG. 3 is a schematic cross-sectional view taken along line VV in FIG. 2. FIG. FIG. 2 is a schematic perspective view showing a state in which the attitude of the tip member in the parallel link mechanism shown in FIG. 1 has been changed. FIG. 7 is a schematic perspective view showing a state in which the attitude of the tip member in the parallel link mechanism shown in FIG. 1 has been changed, viewed from a different angle from that in FIG. 6; 8 is a schematic cross-sectional view taken along line segment VIII-VIII in FIG. 7. FIG. FIG. 3 is a schematic perspective view showing a first example of a mode in which an end effector is attached to a tip member through hole of the parallel link mechanism according to the first embodiment. FIG. 7 is a schematic perspective view showing a second example of a mode in which an end effector is attached to a tip member through hole of the parallel link mechanism according to the first embodiment. FIG. 7 is a schematic perspective view showing a third example of a mode in which an end effector is attached to a tip member through hole of the parallel link mechanism according to the first embodiment. FIG. 3 is a schematic cross-sectional view of a parallel link mechanism according to a second embodiment. 13 is a schematic cross-sectional view taken along line XIII-XIII in FIG. 12. FIG. 14 is an enlarged schematic cross-sectional view of region XIV surrounded by dotted lines in FIG. 13. FIG. FIG. 7 is a schematic perspective view of a link actuating device according to Embodiment 3; FIG. 7 is a schematic perspective view of a link actuating device according to a fourth embodiment. FIG. 7 is a schematic perspective view of a link actuating device according to a fifth embodiment.

Embodiments of the present invention will be described below with reference to the drawings. In the following drawings, the same or corresponding parts are given the same reference numerals, and the description thereof will not be repeated.

(Embodiment 1)
<Configuration of parallel link mechanism>
First, the essential configuration of the parallel link mechanism according to the first embodiment will be briefly described. FIG. 1 is a schematic perspective view showing the configuration of a parallel link mechanism according to the first embodiment. Referring to FIG. 1, parallel link mechanism 10 according to the first embodiment generally includes three link mechanisms 11A, 11B, and 11C. The link mechanism 11A, the link mechanism 11B, and the link mechanism 11C each have a fifth rotating pair R5. The fifth rotating pair portions R5 of each of the link mechanisms 11A, 11B, and 11C are independently arranged at different positions. This is an essential configuration of the parallel link mechanism 10.

FIG. 2 is a schematic front view of the parallel link mechanism shown in FIG. 1. FIG. 3 is a schematic cross-sectional view taken along line III-III in FIG. FIG. 4 is a schematic cross-sectional view taken along line IV-IV in FIG. 3. FIG. 5 is a schematic cross-sectional view taken along line VV in FIG. 2. The configuration of the parallel link mechanism 10 will be described in detail below using FIGS. 1 to 5.

The parallel link mechanism 10 shown in FIGS. 1 to 5 includes a base end member 1, a distal end member 81, and three link mechanisms 11A, 11B, and 11C. The proximal end member 1 is a plate-shaped body having a circular planar shape. In addition, the shape of the proximal end member 1 can be made into arbitrary shapes. For example, the planar shape of the base end member 1 may be a polygonal shape such as a quadrangular shape or a triangular shape, or an elliptical shape or a semicircular shape. Further, the number of link mechanisms 11A to 11C may be three or more, and may be four or five, for example.

The three link mechanisms 11 connect the proximal member 1 and the distal member 81 in a state where the attitude of the distal member 8 with respect to the proximal member 1 can be changed. Each of the three link mechanisms 11 includes first link members 4a, 4b, 4c, second link members 6a, 6b, 6c, third link members 7a, 7b, 7c, and fourth link members 8a, 8b, 8c. . The first link members 4a, 4b, 4c are rotatably connected to the proximal end member 1 at the first rotating pair R1. Specifically, the proximal end connecting portions 2a, 2b, and 2c are installed on the outer periphery of the proximal member 1. The proximal end connecting parts 2a, 2b, and 2c each include a base part 21 fixed to the surface of the proximal member 1, and a shaft part 22 formed so as to protrude from the base part 21 toward the outer circumferential side. The shaft portion 22 is inserted into the through hole 43 of the first link members 4a, 4b, 4c. Nuts 3a, 3b, 3c, which are examples of fixing members, are fixed to the tip portions of the shaft portions 22 protruding from the through holes 43 of the first link members 4a, 4b, 4c. The first link members 4a, 4b, and 4c are rotatable around the shaft portion 22. The shaft portion 22 and the portions of the first link members 4a, 4b, and 4c in which the through hole 43 into which the shaft portion 22 is inserted constitute a first rotating pair portion R1.

The first link members 4a, 4b, and 4c are rod-shaped members extending in an arc shape. The through hole 43 is formed at one end of the first link members 4a, 4b, 4c. As shown in FIG. 3, the inner circumferential surfaces of the first link members 4a, 4b, and 4c are curved when viewed in plan from a direction perpendicular to the surface of the base end member 1. The radius of curvature of the inner circumferential surface in the plan view is smaller than the radius of curvature of the outer circumference of the proximal member 1 . Note that the radius of curvature of the inner circumferential surface may be the same as the radius of curvature of the outer circumference of the proximal end member 1, or may be larger than the radius of curvature of the outer circumference. Moreover, the shape of the first link members 4a, 4b, and 4c may be other than a circular arc shape. For example, the first link members 4a, 4b, and 4c may have a straight rod shape or a rod shape including a bent portion. As shown in FIG. 3, the first link members 4a, 4b, 4c are arranged outside the outer periphery of the proximal end member 1.

A shaft portion 42 is formed at the other end portion 41 of the first link members 4a, 4b, 4c, which is located on the opposite side to the one end portion where the through hole 43 is formed. The shaft portion 42 is formed to extend outward from the outer periphery of the proximal member 1 . The shaft portion 42 is formed on the outer circumferential side surface of the first link members 4a, 4b, 4c, which is opposite to the inner circumferential side surface facing the base end member 1. The shaft portion 42 is inserted into the through hole 63 of the second link members 6a, 6b, 6c. Nuts 5a, 5b, 5c, which are examples of fixing members, are fixed to the tip portions of the shaft portions 42 protruding from the through holes 63 of the second link members 6a, 6b, 6c. The second link members 6a, 6b, and 6c are rotatable around the shaft portion 42. The shaft portion 42 and the portions of the second link members 6a, 6b, and 6c in which the through hole 63 into which the shaft portion 42 is inserted constitute a second rotating pair R2. That is, the second link members 6a, 6b, 6c are rotatably connected to the first link members 4a, 4b, 4c at the second rotating pair R2.

The first central axes 15a, 15b, 15c of the shaft portions 22 in the base end connecting portions 2a, 2b, 2c correspond to the central axis of the first rotating pair portion R1. The second central axes 16a, 16b, 16c of the shaft portions 42 at the other ends 41 of the first link members 4a, 4b, 4c correspond to the central axes of the second rotating pair R2. As shown in FIGS. 1 and 3, the first central axes 15a, 15b, 15c of the shaft portion 22 and the second central axes 16a, 16b, 16c of the shaft portion 42 intersect at the center point 30 of the spherical link. This intersection is a necessary condition, and the first central axes 15a, 15b, 15c of the first rotating pair R1 and the second central axes 16a, 16b, 16c of the second rotating pair R2 are at the center point 30 of the spherical link. If they intersect, the arrangement of the first rotating pair R1 and the second rotating pair R2 can be arbitrarily changed.

The second link members 6a, 6b, and 6c are rod-shaped members that extend linearly. The through hole 63 is formed at one end of the second link members 6a, 6b, 6c. The shape of the second link members 6a, 6b, and 6c may be any shape other than a linearly extending rod shape. For example, the second link members 6a, 6b, 6c may be rod-shaped bodies extending in an arc shape. As shown in FIGS. 1 and 3, the first link members 4a, 4b, 4c are arranged so as to extend along the surface of the proximal end member 1, and the second link members 6a, 6b, 6c are arranged at the proximal end. It is arranged outside the outer periphery of the member 1. Note that the second link members 6a, 6b, and 6c may be arranged at positions overlapping the outer periphery of the proximal end member 1, or may be arranged inside the outer periphery of the proximal end member 1.

A recess for receiving one end of the third link member 7a, 7b, 7c is formed at the other end of the second link member 6a, 6b, 6c opposite to the one end where the through hole 63 is formed. has been done. A through hole is formed at the other end of the second link members 6a, 6b, 6c at a position facing the recess. A through hole is also formed at one end of the third link members 7a, 7b, and 7c. The through holes at the other ends of the second link members 6a, 6b, 6c and the through holes 73 at the one ends of the third link members 7a, 7b, 7c are arranged in a straight line. Connecting members 13a, 13b, 13c are inserted into the through holes at the other ends of the second link members 6a, 6b, 6c and the through holes 73 at one ends of the third link members 7a, 7b, 7c. . The connecting members 13a, 13b, 13c connect the second link members 6a, 6b, 6c and the third link members 7a, 7b, 7c in a relatively rotatable state. The connecting members 13a, 13b, 13c are, for example, bolts and nuts. A third rotating pair portion R3 is constituted by the connecting members 13a, 13b, 13c, the other end portions of the second link members 6a, 6b, 6c, and the one end portions of the third link members 7a, 7b, 7c. That is, the second link members 6a, 6b, 6c and the third link members 7a, 7b, 7c are rotatably connected at the third rotating pair R3.

The third central axes 17a, 17b, 17c of the connecting members 13a, 13b, 13c correspond to the central axes of the third rotating pair R3. The third central axes 17a, 17b, and 17c extend in a direction perpendicular to the second central axes 16a, 16b, and 16c, respectively. Therefore, in the second link members 6a, 6b, 6c, the second central axes 16a, 16b, 16c of the second rotating pair R2 on one end side are the same as the second central axes 16a, 16b, 16c of the third rotating pair R3 on the other end side. It is configured to be orthogonal to each of the three central axes 17a, 17b, and 17c.

The third link members 7a, 7b, and 7c are rod-shaped members that extend linearly. The through hole 73 is formed at one end of the third link members 7a, 7b, and 7c. The shape of the third link members 7a, 7b, and 7c may be any shape other than a linearly extending rod shape. For example, the third link members 7a, 7b, 7c may be rod-shaped bodies extending in an arc shape.

A through hole 74 is formed at the other end of the third link members 7a, 7b, and 7c located on the opposite side from one end where the through hole 73 is formed. The fourth link members 8a, 8b, 8c are formed with recesses for receiving the other ends of the third link members 7a, 7b, 7c. A through hole connected to the recess is formed in the wall portion 83 of the fourth link members 8a, 8b, 8c facing the recess. The through holes 74 at the other ends of the third link members 7a, 7b, 7c and the through holes formed in the walls 83 of the fourth link members 8a, 8b, 8c are arranged in a straight line. Connecting members 14a, 14b, 14c are inserted into the through holes 74 at the other ends of the third link members 7a, 7b, 7c and the through holes in the walls 83 of the fourth link members 8a, 8b, 8c. . The connecting members 14a, 14b, 14c connect the third link members 7a, 7b, 7c and the fourth link members 8a, 8b, 8c in a relatively rotatable state. The connecting members 14a, 14b, 14c are, for example, bolts and nuts. A fourth rotating pair R4 is constituted by the connecting members 14a, 14b, 14c, the other ends of the third link members 7a, 7b, 7c, and the wall portions 83 of the fourth link members 8a, 8b, 8c. That is, the third link members 7a, 7b, 7c and the fourth link members 8a, 8b, 8c are rotatably connected at the fourth rotating pair R4.

The fourth central axes 18a, 18b, 18c of the connecting members 14a, 14b, 14c correspond to the central axis of the fourth rotating pair R4. The fourth central axes 18a, 18b, 18c extend in a direction parallel to the third central axes 17a, 17b, 17c, respectively. That is, the fourth central axes 18a, 18b, 18c, like the third central axes 17a, 17b, 17c, extend in the direction perpendicular to the second central axes 16a, 16b, 16c, respectively.

A wall portion 83 for connection to the third link members 7a, 7b, 7c is formed on the outer peripheral side of the fourth link members 8a, 8b, 8c when viewed from above. The fourth link members 8a, 8b, and 8c extend in a direction along the main surface of the proximal member 1, that is, in a direction from the outer circumferential side to the inner side of the proximal member 1 in plan view. As shown in FIG. 4, the fourth link members 8a, 8b, 8c have a thickness in the vertical direction in the inner region (left side in FIG. 4) than in the outer region (right side in FIG. 4). It may be thinner. A tip member 81 is arranged so as to overlap one end (outer circumferential side) of the fourth ring members 8a, 8b, 8c where the wall portion 83 is formed and the other end (inner side) located on the opposite side. ing. The planar shape of the outer periphery of the tip member 81 is, for example, circular. However, the planar shape of the outer periphery of the tip member 81 is not limited to this. For example, the planar shape of the outer periphery of the tip member 81 may be a polygonal shape such as a quadrangular shape or a triangular shape, or an elliptical shape or a semicircular shape.

The tip member 81 has a central axis 82 located at its center and extending in a direction perpendicular to the upper surface of the tip member 81, as shown in FIG. The parallel link mechanism 10 is characterized in that the center axis 82 of the tip member 81 passes through the spherical link center point 30. The central axis 82 may also pass through the tip member center point 31, for example. The tip member center point 31 is a point located at the center of the tip member 81 in plan view and at the center of the tip member 81 in the thickness direction. A tip member through hole 84 is formed in the tip member 81 at a central portion in plan view, that is, in a region including the central axis 82 . The tip member through hole 84 is a hole provided to penetrate the tip member 81 from one main surface to the other main surface of the disk shape, for example. For example, when the tip member 81 has a circular planar shape, the tip member through hole 84 preferably has a diameter of 1/4 or more and 2/3 or less of the circular diameter of the tip member 81. Among these, it is more preferable that the tip member through hole 84 has a diameter of 1/3 or more and 1/2 or less of the circular diameter of the tip member 81.

As shown in FIG. 4, in the other end side (inside) of each of the fourth link members 8a, 8b, 8c, for example, in a region where the thickness is thinner than the other region, a hole is formed to pass through the region in the vertical direction in the figure. A hole 85 is formed. Further, a through hole 86 is formed in the tip member 81 so as to overlap the through hole 85 . Bolts 9a, 9b, and 9c are inserted through through holes 85 of fourth link members 8a, 8b, and 8c, and through holes 86 directly above the through holes 85, respectively. In FIGS. 1 and 4, the bolts 9a, 9b, and 9c are inserted so that their heads are placed on the through hole 86 side, but conversely, they are inserted so that their heads are placed on the through hole 85 side. Good too. The tips of the bolts 9a, 9b, 9c protruding from the through holes 85 of the fourth link members 8a, 8b, 8c are attached to nuts 9d, 9e (see FIG. 7 described later), 9f (see FIG. 7 described later), which are examples of fixing members. 6) is fixed.

Each of the bolts 9a, 9b, 9c and nuts 9d, 9e, 9f connects each of the fourth link members 8a, 8b, 8c and the tip member 81 in a relatively rotatable state. The other end of the fourth link members 8a, 8b, 8c, the bolts 9a, 9b, 9c, the nuts 9d, 9e, 9f, and the tip member 81 constitute a fifth rotating pair R5. That is, the fourth link members 8a, 8b, 8c and the tip member 81 are rotatably connected at the fifth rotating pair R5.

As can be seen from FIGS. 1, 2, 4, and 5, the fifth rotating pair R5 of each of the three link mechanisms 11A, 11B, and 11C is independently arranged at different positions. In other words, the fifth rotating pair R5 of each of the three link mechanisms 11A, 11B, and 11C are not arranged so as to overlap in one place, but are arranged at separate positions apart from each other. Here, the fifth rotating pair R5 of each of the three link mechanisms 11A, 11B, and 11C is located outside the tip member through hole 84 formed in the center of the tip member 81 in a plan view. They are arranged at intervals along the circumferential direction. More specifically, each of the three link mechanisms 11A, 11B, and 11C is provided outside the tip member through hole 84 having a circular planar shape at a phase interval of 120° in the circumferential direction of the tip member through hole 84. A fifth rotating pair portion R5 is formed. In other words, the tip member through hole 84 is formed in the tip member 81 inside the fifth rotating pair R5 included in each of the three link mechanisms 11A, 11B, and 11C in a plan view. The planar shape of the tip member through hole 84 is not limited to a circular shape, but may be any polygonal shape, elliptical shape, or the like.

The fifth central axis 19a of the bolt 9a and nut 9d shown in FIG. 4 corresponds to the central axis of the fifth rotating pair R5. Similarly, as shown in FIG. 6 described later, a fifth central axis 19b of the bolt 9b and nut 9e, and a fifth central axis 19c of the bolt 9c and nut 9f each correspond to the central axis of the fifth rotating pair R5. do. As shown in FIG. 4, the fifth central axis 19a and the second central axis 16a included in the link mechanism 11A intersect at the central axis intersection 32 (for example, they intersect at right angles). Similarly, the fifth central axis 19b and the second central axis 16b included in the link mechanism 11B intersect at the central axis intersection. The fifth central axis 19c and the second central axis 16c included in the link mechanism 11C intersect at the central axis intersection.

In FIG. 4, the fifth central axis 19a extends in the vertical direction of the figure. On the other hand, the fourth central axis 18a extends through the through hole 74 in the depth direction of the paper. Therefore, the fifth central axis 19a and the fourth central axis 18a are perpendicular to each other in a twisted arrangement. The fourth link members 8a, 8b, 8c are such that the second central axes 18a, 18b, 18c of the fourth rotating pair R4 on one end side are the same as the second central axes 18a, 18b, 18c of the fifth rotating pair R5 on the other end side. It is orthogonal to each of the central axes 19a, 19b, and 19c (so that they are arranged in a mutually twisted manner).

<Operation of parallel link mechanism>
FIG. 6 is a schematic perspective view showing a state in which the attitude of the tip member in the parallel link mechanism shown in FIG. 1 has been changed. FIG. 7 is a schematic perspective view showing a state in which the attitude of the tip member in the parallel link mechanism shown in FIG. 1 has been changed, as viewed from a different angle from that in FIG. FIG. 8 is a schematic cross-sectional view taken along line segment VIII-VIII in FIG. Referring to FIGS. 6 and 7, the tip member 8 The position of can be changed arbitrarily. 6 and 7, by relatively increasing the rotation angle of the first link member 4b around the first central axis 15b, the fourth link member 8b side of the tip member 8 is lifted upward, and the center of the tip member The entire tip member 81 has moved to the side opposite to where the fourth link member 8b is located when viewed from the point 31.

In the parallel link mechanism 10 shown in FIGS. 1 to 8, the tip member 81 moves on a spherical surface centered on the spherical link center point 30 by having the above-described configuration. That is, the attitude of the tip member 8 can be expressed by three-dimensional polar coordinates (r, θ, φ) with the spherical link center point 30 as the origin, as shown in FIG. The bending angle θ here means that a line drawn vertically from the center point 31 of the distal member is the connecting portion between the proximal member 1 and the first link members 4a, 4b, 4c of the first rotating pair R1. This is the angle formed by the central axis 82 of the tip member 81 and a straight line passing through the spherical link center point 30 and a point that intersects a plane including the central axes 15a, 15b, and 15c. The turning angle φ is a straight line that passes through the spherical link center point 30 and the point where a line drawn vertically from the tip member center point 31 intersects with the plane containing the first center axes 15a, 15b, 15c, and the first link. This is the angle formed by the first central axis 15a of the first rotating pair R1 included in the mechanism 11. Further, the center-to-center distance r is the distance between the center point 30 of the spherical link and the center point 31 of the tip member.

As shown in FIGS. 6 and 8, in the link mechanism 11A, among the straight lines perpendicular to the fourth central axis 18a of the fourth rotating pair part R4, a straight line perpendicular to the fifth central axis 19a of the fifth rotating pair part R5. A straight line that overlaps (that is, extends in the same direction so as to match) is defined as the fifth central axis perpendicular L1. Note that the term "perpendicular straight line" here includes a straight line that is deviated within 1 degree from the direction perpendicular to the fifth central axis 19a etc. as an error. Similarly, in the link mechanism 11B, among the straight lines perpendicular to the fourth central axis 18b of the fourth rotating pair R4, the straight lines perpendicular to the fifth central axis 19b of the fifth rotating pair R5 overlap (that is, they coincide). A straight line extending in the same direction as shown in FIG. In the link mechanism 11C, among the straight lines perpendicular to the fourth central axis 18c of the fourth rotating pair part R4, the straight lines perpendicular to the fifth central axis 19c of the fifth rotating pair part R5 overlap (that is, they are aligned in the same direction) The straight line (extending to ) is defined as the fifth central axis perpendicular L3. These fifth central axis perpendicular lines L1, L2, and L3 extend generally along the horizontal direction so as to follow the main surface of the tip member 81. At this time, these three fifth central axis perpendicular lines L1, L2, and L3 intersect with each other at one point, that is, the perpendicular intersection point 131. When the central axis 82 of the distal end member 81 is changed to be inclined with respect to the perpendicular to the main surface of the proximal end member 1 as shown in FIGS. They are placed at positions that do not overlap (shift) visually.

The position of the perpendicular intersection point 131 is not constant. For example, the perpendicular intersection point 131 does not necessarily exist at the position of the tip member center point 31, which is the center of the tip member 81 in plan view. The position of the perpendicular intersection point 131 changes depending on the attitude of the tip member 81. That is, when the main surface of the distal member 81 is arranged so as to be substantially parallel to the main surface of the proximal member 1 as shown in FIG. 1 (when the central axis 82 is substantially perpendicular to the main surface of the proximal member 1), , the perpendicular intersection point 131 is located at a position that substantially coincides with the tip member center point 31 of the tip member 81. On the other hand, when the main surface of the distal member 81 is inclined with respect to the main surface of the proximal member 1 as shown in FIG. (in this case), the perpendicular intersection point 131 is located at a position shifted from the tip member center point 31 of the tip member 81.

As shown in FIG. 7, in the parallel link mechanism 10, the fifth central axes 19a, 19b, and 19c of the fifth rotating pair R5 included in each of the three link mechanisms 11A, 11B, and 11C are parallel to each other. It is preferable. Here, "parallel" includes a case where the angle between the central axes 19a is 1° or less as an error. Further, it is preferable that the fifth central axes 19a, 19b, and 19c are parallel to the central axis 82.

<Effect>
Hereinafter, although some parts overlap with the above, the effects of this embodiment will be explained.

A parallel link mechanism (10) according to the present disclosure includes a base member (1) and three or more link mechanisms (11A, 11B, 11C). Three or more link mechanisms (11A, 11B, 11C) are configured to connect the proximal member (1) and the distal member (81). The three or more link mechanisms (11A, 11B, 11C) can change the attitude of the distal end member (81) with respect to the proximal end member (1). Each of the three or more link mechanisms (11A, 11B, 11C) includes first to fourth link members. The first link members (4a, 4b, 4c) are rotatably connected to the proximal member (1) at the first rotating pair (R1). The second link members (6a, 6b, 6c) are rotatably connected to the first link members (4a, 4b, 4c) at the second rotating pair (R2). The third link members (7a, 7b, 7c) are rotatably connected to the second link members (6a, 6b, 6c) at the third rotating pair (R3). The fourth link members (8a, 8b, 8c) are rotatably connected to the third link members (7a, 7b, 7c) at the fourth rotating pair (R4). The fourth link members (8a, 8b, 8c) are further configured to be rotatably connected to the tip member (81) at the fifth rotating pair (R5). In three or more link mechanisms (11A, 11B, 11C), the first central axis (15a, 15b, 15c) of the first rotating pair part (R1) and the second central axis of the second rotating pair part (R2) (16a, 16b, 16c) intersect at the spherical link center point (30). The fifth rotating pair portions (R5) of the three or more link mechanisms (11A, 11B, 11C) are independently arranged at different positions.

In this way, each of the three or more link mechanisms 11A to 11C has a five-bar chain structure having the first rotating pair portion R1 to the fifth rotating pair portion R5. Therefore, the distal end member 81 can be moved with respect to the proximal end member 1 with a total of three degrees of freedom: two degrees of freedom in rotation around the spherical link center point 30 and one degree of freedom in the direction along the fifth central axis 19a to 19c. can be done. Therefore, the tip member 81 can be moved relative to the proximal member 1 along a spherical surface centered on the spherical link center point 30, and independently of the movement along the spherical surface, the distal end member 81 can be moved at the fifth center. It can also be moved in directions along the axes 19a to 19c. As a result, since the tip member 81 can be moved along the spherical surface and the radius of the spherical surface along which the tip member 81 moves can be adjusted, the tip of the tip can be moved more easily than if the tip member 81 could only move along a spherical surface with a constant radius. The movable range of the member 81 can be increased. Note that the fourth link members 8a, 8b, 8c are configured to be rotatably connected to the tip member 81 at the fifth rotating pair R5, which means the fourth link members 8a, 8b, 8c. This means that there is a portion to which a tip member as a separate member can be connected, and also includes the case where a part of the fourth link members 8a, 8b, 8c functions as the tip member.

Further, in this case, since the fifth rotating pair portions R5 of the three or more link mechanisms 11A to 11C are arranged at different positions, for example, the three or more fifth rotating pair portions R5 are arranged at different positions. It can be placed in a relatively outer region in plan view. Therefore, the working body (end effector) can be provided in a relatively inner region of the tip member 81 in a plan view. In this way, the moment of inertia during operation of the end effector can be reduced compared to the case where the end effector is provided relatively outside of the tip member 81. As a result, the operational accuracy of the end effector can be improved and vibrations of the parallel link mechanism 10 can be suppressed. Therefore, the life of the parallel link mechanism 10 can be improved.

In the parallel link mechanism (10), the tip member (81) has a tip located inside the fifth rotating pair (R5) included in each of the three or more link mechanisms (11A, 11B, 11C) in a plan view. Preferably, a member through hole (84) is formed. As described above, if the fifth rotating pair R5 of each of the three or more link mechanisms 11A to 11C is provided at different positions, for example, in the outer region of the tip member 81 in a plan view, then the tip member 81 can be A space is obtained for forming the tip member through hole 84 inside the hole. By attaching the end effector to the tip member through hole 84, the end effector can be stably installed in the inner region of the tip member 81 in plan view. Therefore, as described above, compared to the case where the end effector is provided relatively outside of the tip member 81, the moment of inertia during operation of the end effector can be reduced. As a result, the operational accuracy of the end effector can be improved and vibrations of the parallel link mechanism 10 can be suppressed. Therefore, the life of the parallel link mechanism 10 can be improved.

FIG. 9 is a schematic perspective view showing a first example of a mode in which an end effector is attached to the tip member through hole of the parallel link mechanism according to the first embodiment. FIG. 10 is a schematic perspective view showing a second example of a mode in which an end effector is attached to the tip member through hole of the parallel link mechanism according to the first embodiment. FIG. 11 is a schematic perspective view showing a third example of a mode in which an end effector is attached to the tip member through hole of the parallel link mechanism according to the first embodiment. Referring to FIG. 9, the tip member through hole 84 is a hole formed to pass through the tip member 81 from, for example, a disc-shaped one main surface 81a to the other main surface 81b on the opposite side. Department. As shown in FIG. 9, an end effector 101 is attached so as to fit into the tip member through hole 84, for example. However, in FIG. 9, most of the end effector 101 is located outside one main surface 81a of the tip member 81. The end effector 101 attached to the inner region of the tip member 81 in plan view reduces the moment of inertia during operation and suppresses vibration, thereby improving the life of the parallel link mechanism 10. The end effector 101 faces outside the area surrounded by the three link mechanisms of the parallel link mechanism 10. Therefore, the end effector 101 is a working body that performs work on a member disposed outside the parallel link mechanism 10, such as an ink ejection device.

Referring to FIG. 10, end effector 102 is fitted into tip member through hole 84, for example, similarly to end effector 101 of FIG. Like the end effector 101, the end effector 102 also faces outside the area surrounded by the three link mechanisms of the parallel link mechanism 10. However, the distance from the tip of end effector 102 to one main surface 81a of tip member 81 is smaller than the distance in the configuration shown in FIG.

Referring to FIG. 11, end effector 101 has an area surrounded by three link mechanisms of parallel link mechanism 10 on the other main surface 81b in plan view of tip member 81 where tip member through hole 84 is not provided. It may be installed so that it faces inward.

In the parallel link mechanism (10), a line perpendicular to the fourth central axis (18a, 18b, 18c) of the fourth rotating pair (R4) included in each of the three or more link mechanisms (11A, 11B, 11C) Among the straight lines, the fifth central axis perpendicular lines (L1, L2, L3), which are straight lines that overlap with the straight line perpendicular to the fifth central axis (19a, 19b, 19c) of the fifth rotating pair part (R5), meet the perpendicular intersection point (131 ) is preferable. In this way, when viewed from the spherical link center point 30 on the proximal member 1, the distal member 81 has two degrees of freedom in rotation about the spherical link center point 30 and one degree of freedom in the direction along the central axis 82. It can be moved with a total of three degrees of freedom. Therefore, the distal end member 81 can be moved relative to the proximal end member 1 along a spherical surface centered on the spherical link center point 30, and the central axis 81 can be moved independently of the movement along the spherical surface. It can also be moved in the direction along.

In the parallel link mechanism (10), it is preferable that the fifth central axes (19a, 19b, 19c) of the fifth rotating pair (R5) included in each of the three or more link mechanisms are parallel to each other. In this way, the operation of the parallel link mechanism 10 can be easily controlled.

In the parallel link mechanism (10), the fifth central axis (19a, 19b, 19c) and the second central axis (16a, 16b, 16c) included in each of the three or more link mechanisms (11A, 11B, 11C) It is preferable that they intersect at the central axis intersection (32). No matter how the attitude of the tip member 81 is changed, by satisfying the above conditions, the operation of the parallel link mechanism 10 can be easily controlled.

(Embodiment 2)
<Configuration of parallel link mechanism>
FIG. 12 is a schematic cross-sectional view of the parallel link mechanism according to the second embodiment. FIG. 13 is a schematic cross-sectional view taken along line XIII-XIII in FIG. 12. FIG. 14 is an enlarged schematic cross-sectional view of region XIV surrounded by dotted lines in FIG. Note that FIG. 12 corresponds to FIG. 3, and FIG. 13 corresponds to FIG. 4.

The parallel link mechanism 20 shown in FIGS. 12 and 13 basically has the same configuration as the parallel link mechanism 10 shown in FIGS. 1 to 5, but the first rotating pair R1 to the fifth rotating pair R5 It differs from the parallel link mechanism 10 shown in FIGS. 1 to 5 in that bearings 25 to 29 are installed as rotational resistance reducing means in each of the parts, and a tip member through hole 84 is not formed in the tip member 81. ing. In addition, in FIGS. 12 and 13, bearings 25 to 29 are installed in all the rotating pair parts, but a bearing is installed in at least one of the first rotating pair part R1 to the fifth rotating pair part R5. You can do it like this.

Each bearing 25-29 is attached to each link mechanism using the shaft portions 22, 42 or bolts and nuts. Specifically, as shown in FIG. 12, in the first rotating pair portion R1, a bearing 25 is provided between the shaft portion 22 of the base end connection portions 2a, 2b, 2c and the first link member 4a, 4b, 4c. It is located. As the bearing 25, a rolling bearing of any configuration, such as a ball bearing, can be used. For example, the outer ring of the bearing 25 may be fixed to the first link members 4a, 4b, and 4c. Further, the inner ring of the bearing 25 connected to the shaft portion 22 may be fixed while being sandwiched between the nuts 3a, 3b, 3c and the base portion 21.

In the second rotating pair R2, a bearing 26 is arranged between the shaft portion 42 of the first link member 4a, 4b, 4c and the second link member 6a, 6b, 6c. For example, the outer ring of the bearing 26 may be fixed to the second link members 6a, 6b, and 6c. Further, the inner ring of the bearing 26 connected to the shaft portion 42 may be fixed while being sandwiched between the nuts 5a, 5b, 5c and the first link members 4a, 4b, 4c.

In the third rotating pair R3, a bearing 27 is arranged as shown in FIG. 13 between the connecting members 13a, 13b, 13c (see FIG. 2) and the third link members 7a, 7b, 7c (see FIG. 2). ing. For example, the outer ring of the bearing 27 may be fixed to the third link members 7a, 7b, and 7c. Any method can be used to fix the outer ring of the bearing 27 to the third link members 7a, 7b, and 7c. For example, a hole for inserting an outer ring may be formed in the third link members 7a, 7b, and 7c, and the outer ring may be fixed in the hole by press-fitting the outer ring into the hole. Moreover, any method can be used for fixing the inner ring of the bearing 27 to the connecting members 13a, 13b, and 13c. For example, consider a case where a rod-shaped body such as a fully screwed body, and a set of washers and a set of nuts arranged at both ends of the rod-shaped body are used as the connecting members 13a, 13b, and 13c. In this case, the opening in the inner ring of the bearing 27 is disposed inside the through hole at one end of the second link members 6a, 6b, 6c and the through hole at one end of the third link member 7a, 7b, 7c. A rod-shaped body is arranged so as to pass through. A washer and a nut are arranged at both ends of the rod-shaped body. By tightening the nut, one end of the second link members 6a, 6b, 6c and the washer are pressed against the inner ring of the bearing 27, thereby applying preload to the inner ring. As a result, the inner ring of the bearing 27 is fixed to the second link members 6a, 6b, 6c via the connecting members 13a, 13b, 13c.

In the fourth rotating pair R4, a bearing 28 is arranged between the connecting members 14a, 14b, 14c (see FIG. 2) and the third link members 7a, 7b, 7c (see FIG. 2) as shown in FIG. ing. For example, the outer ring of the bearing 28 may be fixed to the third link members 7a, 7b, and 7c. Furthermore, any method can be used for fixing the inner ring of the bearing 28 to the connecting members 14a, 14b, and 14c, but it is possible to use the same method as the method of fixing the inner ring of the bearing 27 in the third rotating pair R3. Good too.

In the fifth rotating pair R5, a bearing 29 is arranged between the tip member 81 and the bolts 9a, 9b, 9c inserted into the through hole 86 formed therein, as shown in FIGS. 13 and 14. has been done. For example, the outer ring of the bearing 29 may be fixed to the through hole 86 on the tip member 81 side by a method such as press fitting. Further, the method of fixing the inner ring of the bearing 29 to the bolts 9a, 9b, and 9c may be, for example, the following method. That is, as shown in FIG. 14, bolts 9a, 9b, 9c are inserted into the inner ring side, and nuts 9d, 9e, 9f are arranged at the ends of the bolts 9a, 9b, 9c on the opposite side from the heads. At this time, washers W are sandwiched between the bearing 29 and the heads of the bolts 9a, 9b, and 9c, and between the bearing 29 and the nuts 9d, 9e, and 9f. In this way, the bearing 29 located between the tip member 81 and the bolts 9a to 9c is sandwiched between the heads of the bolts 9a to 9c and the nuts 9d, 9e, and 9f with the washer W interposed. By tightening the nuts in this state, the bolts 9a to 9c and washers W are pressed against the inner ring of the bearing 29, thereby applying preload to the inner ring. As a result, the inner ring of the bearing 29 is fixed to the bolts 9a to 9c.

Although bearings 25 to 29 are used as rotational resistance reducing means in FIGS. 12 to 14, members other than bearings may be used as long as the rotational resistance can be reduced.

<Effect>
In the parallel link mechanism (20), at least one of the first rotating pair (R1) to the fifth rotating pair (R5) may include a bearing (25-29). In this case, the movement of the rotating pair in which the bearings 25 to 29 are installed can be made smoother, and the positioning accuracy of the tip member 8 can be improved. In addition, by installing the bearings 25 to 29, it is possible to suppress heat generation in the rotating pair by reducing the friction torque of the rotating pair in which the bearing is installed, and as a result, the life of the rotating pair can be reduced. It can be extended. Furthermore, by installing the bearings 25 to 29, rattling during operation of the rotating pair can be suppressed more than when the bearings 25 to 29 are not used.

(Embodiment 3)
<Configuration of link actuating device>
FIG. 15 is a schematic perspective view of a link actuating device according to Embodiment 3. Note that FIG. 15 corresponds to FIG. 1.

The link actuating device 110 shown in FIG. 15 includes the parallel link mechanism 10 shown in FIGS. 1 to 5 and attitude control drive sources 35a, 35b, and 35c. Attitude control drive sources 35a, 35b, and 35c are installed in all three link mechanisms 11A, 11B, and 11C. The posture control drive sources 35a, 35b, 35c change the rotation angle of the first link members 4a, 4b, 4c about the first central axes 15a, 15b, 15c, thereby controlling the distal end member 8 relative to the proximal end member 1. Change your posture arbitrarily.

As shown in FIG. 15, the posture control drive sources 35a, 35b, and 35c are connected to the base end member 1 by being fixed to fixing portions 36a, 36b, and 36c, respectively. The fixing parts 36a, 36b, and 36c are installed on the outer periphery of the surface of the proximal member 1. The shapes of the fixing parts 36a, 36b, and 36c can be arbitrary, but are plate-shaped, for example.

The posture control drive sources 35a, 35b, and 35c may be of any configuration, such as an electric motor, as long as it can generate rotational driving force. The attitude control drive sources 35a, 35b, and 35c each include a rotatable shaft 37. The rotating shaft 37 is inserted into the through hole 43 (see FIG. 3) of the first link members 4a, 4b, 4c and fixed with nuts 3a, 3b, 3c. That is, the first link members 4a, 4b, and 4c are fixed to the rotating shaft 37. The rotation of the rotating shaft 37 causes the first link members 4a, 4b, 4c to rotate around the first central axes 15a, 15b, 15c. Here, the first central axes 15a, 15b, and 15c are central axes of the rotating shaft 37.

The attitude control drive sources 35a, 35b, and 35c are arranged at positions overlapping with the first central axes 15a, 15b, and 15c. Further, the posture control drive sources 35a, 35b, and 35c are disposed on the surface side of the proximal member 1 on the distal member 8 side, so as to protrude outward from the outer periphery of the proximal member 1.

With such a configuration, the attitude of the distal end member 81 with respect to the proximal end member 1 can be uniquely determined depending on the state of each link mechanism 11A to 11C (see FIG. 1). That is, by controlling the postures of the first link members 4a, 4b, 4c with respect to the base end member 1, or the rotation angles of the first link members 4a, 4b, 4c around the first central axes 15a, 15b, 15c, The attitude of the tip member 81 can be controlled.

Note that when three or more link mechanisms 11A to 11C (see FIG. 1) are installed in the link actuating device 110, at least three of the three or more link mechanisms 11 are provided with an attitude control drive source 35a, 35b and 35c may be installed.

<Effect>
A link actuating device (110) according to the present disclosure includes the parallel link mechanism (10, 20) and an attitude control drive source (35a, 35b, 35c). The posture control drive sources (35a, 35b, 35c) are installed in at least three link mechanisms (11A to 11C) among the three or more link mechanisms (11A to 11C), and are installed in at least three link mechanisms (11A to 11C), and are arranged to connect the distal end member to the base end member (1). The posture of (81) is arbitrarily changed.

In this case, the at least three posture control drive sources 35a, 35b, and 35c individually control the link mechanisms 11A, 11B, and 11C, so that the tip member 81 can be operated over a wide range and precisely. Further, by using the parallel link mechanism 10 as described above, a lightweight and compact link actuating device 110 can be realized.

(Embodiment 4)
<Configuration of link actuating device>
FIG. 16 is a schematic perspective view of a link actuating device according to Embodiment 4. The link actuating device 120 shown in FIG. 16 basically has the same configuration as the link actuating device 110 shown in FIG. 15, but the arrangement of the attitude control drive sources 35a, 35b, and 35c is different from that shown in FIG. Different from link actuator. In the link actuating device 120 shown in FIG. 16, the posture control drive sources 35a, 35b, and 35c are arranged on the surface of the proximal member 1 on the distal member 81 side and inside the outer periphery of the proximal member 1. There is. Fixing parts 36a, 36b, and 36c that fix the posture control drive sources 35a, 35b, and 35c are fixed to the base end member 1 on the inner peripheral side of the first link members 4a, 4b, and 4c. Attitude control drive sources 35a, 35b, 35c are arranged on the inner peripheral side of the fixed parts 36a, 36b, 36c.

<Effect>
With such a configuration, the same effects as the link actuating device shown in FIG. 15 can be obtained. Furthermore, since the posture control drive sources 35a, 35b, and 35c are arranged inside the outer periphery of the proximal end member 1, the area occupied by the device can be smaller than that of the link actuating device shown in FIG.

(Embodiment 5)
<Configuration of link actuating device>
FIG. 17 is a schematic perspective view of a link actuating device according to Embodiment 5. The link actuating device 130 shown in FIG. 17 basically has the same configuration as the link actuating device 120 shown in FIG. The structure of the connecting portion between 35a, 35b, 35c and the first link members 4a, 4b, 4c is different from the link actuating device 120 shown in FIG. 16. In the link actuating device 130 shown in FIG. 17, the posture control drive sources 35a, 35b, and 35c are arranged on the back side of the base end member 1. That is, the posture control drive sources 35a, 35b, and 35c are connected to the back surface of the proximal end member 1 opposite to the surface facing the distal end member 81. The method of fixing the posture control drive sources 35a, 35b, and 35c to the back surface of the base end member 1 is basically the same as that of the link actuating device 120 shown in FIG. 16. Taking the posture control drive source 35a as an example, the posture control drive source 35a is connected to a fixing portion 36a fixed to the back surface of the base member 1. A gear 38 is fixed to the rotation shaft 37 of the attitude control drive sources 35a, 35b, and 35c. A gear 39 is installed to mesh with the gear 38. The gear 39 is rotatably installed on the shaft portion 22 of the base end connection portions 2a, 2b, 2c on the surface side of the base end member 1. The gear 39 is fixed to the first link members 4a, 4b, and 4c. In this way, the rotation of the rotation shafts 37 of the posture control drive sources 35a, 35b, 35c causes the first link members 4a, 4b, 4c to be connected to the first center shafts 15a, 15b, It can be rotated around 15c.

<Effect>
With such a configuration, the same effects as the link actuating device 110 shown in FIG. 15 can be obtained. Furthermore, since the posture control drive sources 35a, 35b, and 35c are arranged on the back side of the proximal member 1, the posture control drive sources 35a, 35b, and 35c are connected to the link mechanisms 11A to 11C (see FIG. 1). This can prevent interference with movement. Furthermore, since the posture control drive sources 35a, 35b, and 35c are arranged at positions overlapping the base end member 1 in a plan view, the area occupied by the device can be smaller than that of the link actuating device shown in FIG. 15.

Note that the link actuating device may be configured by applying the posture control drive sources 35a, 35b, and 35c shown in any of FIGS. 15 to 17 to the parallel link mechanism in each of the embodiments described above. . Further, in each embodiment, a case is shown in which the number of link mechanisms 11 is three, but the number of link mechanisms 11 may be any number greater than or equal to four, such as five, six, eight, etc.

Each of the embodiments disclosed this time should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is indicated by the claims rather than the above description, and it is intended that all changes within the meaning and range equivalent to the claims are included.

1 Base end member, 2a, 2b, 2c Base end connection portion, 3a, 3b, 3c, 5a, 5b, 5c, 9d, 9e, 9f Nut, 4a, 4b, 4c First link member, 6a, 6b, 6c 2 link members, 7a, 7b, 7c 3rd link members, 8a, 8b, 8c 4th link members, 10, 20 Parallel link mechanisms, 11A, 11B, 11C Link mechanisms, 13a, 13b, 13c, 14a, 14b, 14c Connection member, 15a, 15b, 15c First central axis, 16a, 16b, 16c Second central axis, 17a, 17b, 17c Third central axis, 18a, 18b, 18c Fourth central axis, 19a, 19b, 19c Fifth Central axis, 21 Base portion, 22, 42 Shaft portion, 25, 26, 27, 28, 29 Bearing, 30 Spherical link center point, 31 Tip member center point, 32 Center axis intersection point, 35a, 35b, 35c Attitude control drive Source, 36a, 36b, 36c Fixed part, 37 Rotating shaft, 41 Other end, 43, 63, 73, 74, 85, 86 Through hole, 81 Tip member, 81a One main surface, 81b Other main surface, 82 central axis, 83 wall, 84 tip member through hole, 101, 102 end effector, 110, 120, 130 link actuator, L1, L2, L3 5th central axis perpendicular, R1 1st rotation pair, R2 2nd rotation Pair part, R3 3rd rotation pair part, R4 4th rotation pair part, R5 5th rotation pair part.

Claims (6)

a proximal member;
Equipped with three or more link mechanisms,
The three or more link mechanisms are configured to connect the proximal member and the distal member,
The three or more link mechanisms are capable of changing the attitude of the distal end member with respect to the proximal end member,
Each of the three or more link mechanisms includes:
a first link member rotatably connected to the proximal member at a first rotating pair;
a second link member rotatably connected to the first link member at a second rotating pair;
a third link member rotatably connected to the second link member at a third rotating pair;
a fourth link member rotatably connected to the third link member at a fourth rotating pair;
The fourth link member is configured to be rotatably connected to the tip member at a fifth rotating pair,
In the three or more link mechanisms, the first central axis of the first rotating pair and the second central axis of the second rotating pair intersect at a center point of the spherical link,
The fifth rotating pair portions of each of the three or more link mechanisms are independently arranged at different positions ,
Among the straight lines perpendicular to the fourth central axis of the fourth rotating pair included in each of the three or more link mechanisms, a straight line that overlaps with a straight line perpendicular to the fifth central axis of the fifth rotating pair A parallel link mechanism in which the five central axes perpendiculars intersect at the perpendicular intersection . The parallel link mechanism according to claim 1 , wherein the fifth central axes of the fifth rotating pair included in each of the three or more link mechanisms are parallel to each other. The parallel link mechanism according to claim 1 or 2, wherein the fifth central axis and the second central axis included in each of the three or more link mechanisms intersect at a central axis intersection. Any one of claims 1 to 3, wherein the tip member has a tip member through hole formed inside the fifth rotating pair included in each of the three or more link mechanisms in a plan view. Parallel link mechanism described in . The parallel link mechanism according to any one of claims 1 to 4 , wherein at least one of the first to fifth rotating pairs includes a bearing. A parallel link mechanism according to any one of claims 1 to 5 ,
A link actuating device comprising: a posture control drive source installed in at least three link mechanisms among the three or more link mechanisms and arbitrarily changing the posture of the distal end member with respect to the proximal end member.

Images