Actuator and joint device for robots

Abstract

The application discloses an actuator and a joint device for a robot, and relates to the technical field of robots. The actuator comprises a fixed component, a movable component, a supporting component and a pair of driving components. The supporting component mechanically connects the fixed component and the movable component. The pair of driving components mechanically connect the fixed component and the movable component and are capable of stretching and contracting respectively. The pair of driving components are located in a sector region with an apex angle less than 180 degrees and with the supporting component as the apex. The pair of driving components drive the movable component relative to the fixed component with at least two degrees of freedom with the supporting component as the fulcrum.

Description

Technical Field

[0001] This invention relates to the field of robotics, and in particular to an actuator and a joint device for robots. Background Technology

[0002] In related technologies, it is known to use a drive unit composed of a voice coil linear actuator to drive a movable part (platform) with at least two degrees of freedom (e.g., patent document EP3056228A1). This motion mechanism includes three drive units (linear actuators) that drive a movable part supported by a support member (column) disposed at the center of the three drive units.

[0003] In the motion mechanism involved in the related technology, the support member supports the movable member through a magnetic ball joint. Furthermore, the two ends of each of the three drive units also form magnetic ball joints, thereby enabling the movable member to perform three-degree-of-freedom motion with the support member as the fulcrum. Summary of the Invention

[0004] In the structures involved in the aforementioned related technologies, in order to achieve at least two degrees of freedom (three degrees of freedom), three driving units are required, and these three driving units need to be combined for control, which makes the structure and control prone to becoming complex.

[0005] The present invention is made in view of the above circumstances, and its object is to provide a simplified actuator and joint device for robots that is easy to implement in terms of structure and control.

[0006] One embodiment of the present invention relates to an actuator comprising a fixed member, a movable member, a support member, and a pair of drive units. The support member mechanically connects the fixed member and the movable member. The pair of drive units mechanically connect the fixed member and the movable member, and are respectively capable of extension and retraction. The pair of drive units are located within a sector-shaped region with a vertex angle of less than 180 degrees centered on the support member. The pair of drive units, using the support member as a fulcrum, drive the movable member with at least two degrees of freedom relative to the fixed member.

[0007] One embodiment of the present invention relates to a robotic joint device comprising the actuator, a first component, and a second component. The first component is fixed to the fixed component. The second component is fixed to the movable component.

[0008] According to the present invention, there is an advantage in providing simplified actuators and robot joint devices with easily achievable structures and controls. Attached Figure Description

[0009] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0010] Figure 1 This is a perspective view showing the schematic structure of the actuator according to Embodiment 1.

[0011] Figure 2 This is a schematic diagram of a robot that uses the same actuator as a joint device.

[0012] Figure 3 This is a schematic exploded perspective view of the actuator as described above.

[0013] Figure 4 The main part of the actuator shown above is... Figure 5 A rough cross-sectional view of the A1-A1 line section.

[0014] Figure 5 This is a schematic top view of the actuator as described above.

[0015] Figure 6 This is a schematic right view showing the operation of the same actuator.

[0016] Figure 7 This is a schematic front view showing the operation of the actuator as described above.

[0017] Figure 8 This is a perspective view showing the schematic structure of the actuator involved in Embodiment 2.

[0018] Figure 9 This is a perspective view showing the schematic structure of the actuator involved in Embodiment 3.

[0019] Figure 10 This is a perspective view showing the schematic structure of the actuator involved in Embodiment 4.

[0020] Figure 11 This is a perspective view showing the schematic structure of the actuator involved in Embodiment 5.

[0021] Explanation of icon numbers:

[0022] 1, 1A, 1B, 1C, 1D: Actuators;

[0023] 110: Joint devices for robots;

[0024] 3, 4: Drive unit;

[0025] 5: Support components;

[0026] 6: Driven cylinder;

[0027] 21: Fixed components;

[0028] 22: Movable parts;

[0029] 32, 42: Second joint section;

[0030] 51: First joint;

[0031] 61, 62: Third joint section;

[0032] 111: First component;

[0033] 112: Second component;

[0034] R1: Sector-shaped region.

[0035] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0037] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0038] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0039] (Implementation Method 1)

[0040] (1) Summary

[0041] The following is for reference Figure 1 and Figure 2 The actuator 1 according to this embodiment will be described in general. The accompanying drawings referenced in this invention are schematic diagrams, and the size and thickness ratios of the structural elements shown do not necessarily reflect the actual size ratios. For example, Figure 1 and Figure 2 The shapes and sizes of the fixed part 21 and the movable part 22 shown are merely illustrative and are not intended to be limited to the shapes and sizes shown in the illustration.

[0042] In this embodiment, for ease of explanation, the following is used Figure 1 The left-right direction D1, front-back direction D2, and up-down direction D3 are shown to define the orientation of actuator 1. The left-right direction D1, front-back direction D2, and up-down direction D3 are orthogonal to each other. However, these directions are not intended to define the operating orientation (direction during use) of actuator 1.

[0043] like Figure 1 As shown, the actuator 1 according to this embodiment includes a fixed part 21 and a movable part 22. The actuator 1 drives the movable part 22 with at least two degrees of freedom relative to the fixed part 21. The actuator 1 is a device that converts some kind of energy, such as electrical energy, into kinetic energy to perform mechanical motion. As a driving method for the actuator 1, various driving methods can be used, such as electric, hydraulic, or pneumatic, or combinations thereof. In this embodiment, as an example, the actuator 1 is assumed to be an electric actuator that is driven by being supplied with electricity and drives the movable part 22 by converting electrical energy into kinetic energy.

[0044] In this invention, "degree of freedom" refers to a parameter indicating the ease of relative movement between two components (fixed component 21 and movable component 22 in actuator 1), particularly concerning rotational movements, and specifically the number of axes of rotation. For example, when movable component 22 is driven with "one degree of freedom," it can only perform rotational movements centered on one axis of rotation. In contrast, when movable component 22 is driven with "two degrees of freedom," it can perform rotational movements centered on two axes of rotation, and when it is driven with "three degrees of freedom," it can perform rotational movements centered on three axes of rotation.

[0045] In the actuator 1 of this embodiment, the movable part 22 has at least two degrees of freedom in its rotational movement (rotational motion) relative to the fixed part 21. That is, the movable part 22 is driven with two, three, or four or more degrees of freedom relative to the fixed part 21.

[0046] In this embodiment, as an example, the actuator 1 has two degrees of freedom. Specifically, the movable member 22 is configured to perform a two-degree-of-freedom rotational movement relative to the fixed member 21 about the fulcrum P1. That is, the movable member 22 can perform rotational movements about two rotation axes (the first rotation axis Ax1 and the second rotation axis Ax2).

[0047] In this invention, the term "rotation axis" refers to an imaginary axis (straight line) that serves as the center of rotational motion of the rotating body (movable part 22, etc.). That is, both the first rotation axis Ax1 and the second rotation axis Ax2 are imaginary axes without any physical form. Here, both the first rotation axis Ax1 and the second rotation axis Ax2 pass through the fulcrum P1 and, when viewed from above (refer to...),... Figure 5 The rotation axes intersect each other (orthogonal in this embodiment). That is, the first rotation axis Ax1 and the second rotation axis Ax2 intersect each other (orthogonally) at the fulcrum P1.

[0048] As an example, the first rotation axis Ax1 is a straight line along the left-right direction D1, and the second rotation axis Ax2 is a straight line along the front-back direction D2. That is, the movable part 22 swings in the up-down direction D3 at both ends in the front-back direction D2 by rotating around the first rotation axis Ax1, and swings in the up-down direction D3 at both ends in the left-right direction D1 by rotating around the second rotation axis Ax2. Hereinafter, the rotation centered on the first rotation axis Ax1 will be called "pitch", and the rotation centered on the second rotation axis Ax2 will be called "roll". That is, the first rotation axis Ax1 is the pitch axis, and the second rotation axis Ax2 is the roll axis.

[0049] like Figure 2As shown, the actuator 1 involved in this embodiment is, for example, a joint device (robot joint device 110) used in a robot 100 such as an industrial robot. As a robot 100, there are, for example, humanoid robots that can perform more complex movements and thus handle a wider variety of tasks. Such a robot 100 includes multiple (many) robot joint devices 110 that are equivalent to human joints.

[0050] like Figure 2 As shown, the robot joint device 110 includes an actuator 1, a first component 111, and a second component 112. As described above, the actuator 1 drives the movable component 22 with two or more degrees of freedom (two degrees of freedom in this embodiment) relative to the fixed component 21. The first component 111 is fixed to the fixed component 21 of the actuator 1. The second component 112 is fixed to the movable component 22. Thus, the robot joint device 110 can drive the second component 112 with two or more degrees of freedom (two degrees of freedom in this embodiment) relative to the first component 111.

[0051] Such a robot joint device 110 functions as a human joint and muscle, and can achieve flexion, extension, and / or twisting movements between the first component 111 and the second component 112 by driving the actuator 1. In this embodiment, as described above, since the actuator 1 is an electric actuator, it is driven by electrical control, thereby enabling the robot joint device 110 to perform movements similar to human joints.

[0052] Furthermore, by including multiple robotic joint devices 110 as described above, the robot 100 is able to perform complex movements that mimic human actions, and can handle a wider variety of tasks. The multiple robotic joint devices 110 applied to the robot 100 can be of the same specification or can include robotic joint devices 110 of different specifications. For example, the robotic joint device 110 for the elbow portion of the robot 100 may include a two-degree-of-freedom actuator 1, and the robotic joint device 110 for the wrist portion of the robot 100 may include a three-degree-of-freedom actuator 1.

[0053] (2) Details

[0054] The following is for reference Figures 1 to 7 The detailed structure of the actuator 1 involved in this embodiment will be described.

[0055] In addition to the fixed component 21 and the movable component 22, actuator 1 also includes a support component 5 and a pair of drive units 3 and 4. The support component 5 mechanically connects the fixed component 21 and the movable component 22. The pair of drive units 3 and 4 mechanically connect the fixed component 21 and the movable component 22. The pair of drive units 3 and 4 are extendable and retractable. The pair of drive units 3 and 4 are located in a fan-shaped region R1 (refer to...) with a apex angle less than 180 degrees centered on the support component 5. Figure 5 Inside. A pair of drive units 3 and 4 drive the movable member 22 with at least two degrees of freedom relative to the fixed member 21, using the support member 5 as a fulcrum. In this embodiment, as described above, since the actuator 1 has "two degrees of freedom", the pair of drive units 3 and 4 drive the movable member 22 with "two degrees of freedom" relative to the fixed member 21.

[0056] In this invention, the "apex" of the sector region R1 refers to the corner with the central angle (vertical angle) of the sector region R1, and the point where the straight lines (i.e., the part equivalent to the radius) of the sector region R1 intersect. In short, when a sector region R1 with a vertex angle of less than 180 degrees is cut from a circle centered on the support member 5, a pair of drive units 3 and 4 are located within the sector region R1.

[0057] According to this structure, a pair of drive units 3 and 4 located in a sector-shaped region R1 with a vertex angle of less than 180 degrees, with the support member 5 as the fulcrum, can drive the movable member 22 with at least two degrees of freedom relative to the fixed member 21. Thus, two degrees of freedom can be achieved with a pair (two) drive units 3 and 4, which has the advantage of simplifying the structure and control compared to related technologies that require three drive units.

[0058] More specifically, such as Figure 1 and Figure 3 As shown, in this embodiment, the fixed member 21 and the movable member 22 are both plate-shaped members with thickness in the vertical direction D3. As an example, both the fixed member 21 and the movable member 22 are made of metal and have a thickness that provides sufficient strength.

[0059] As an example, the fixed component 21 is roughly triangular in shape when viewed from above. That is, the fixed component 21 is shaped like a triangular plate. As an example, the movable component 22 is roughly circular in shape when viewed from above. That is, the movable component 22 is shaped like a disc.

[0060] Furthermore, the plate-shaped fixed member 21 and the movable member 22 are arranged opposite each other at a predetermined interval in the vertical direction D3. The movable member 22 is located above the fixed member 21. Here, the fixed member 21 is formed to be slightly smaller than the movable member 22, so that the fixed member 21 is accommodated within the projection plane of the movable member 22. Moreover, when viewed from above, the center of the fixed member 21 coincides with the center of the movable member 22, and the center of the movable member 22 is located directly above the center of the fixed member 21.

[0061] The support member 5 and a pair of drive parts 3 and 4 are located between the fixed member 21 and the movable member 22, mechanically connecting the fixed member 21 and the movable member 22. In other words, the movable member 22 is supported above the fixed member 21 by the support member 5 and the pair of drive parts 3 and 4.

[0062] As an example, the support member 5 is formed as a generally cylindrical shape with a length in the vertical direction D3. The support member 5 mechanically connects the center of the fixed member 21 to the center of the movable member 22. As an example, the support member 5 is made of metal and has a thickness (diameter) that provides sufficient strength.

[0063] The lower end of the support member 5, i.e. the end on the side of the fixed member 21, is fixed to the fixed member 21 by a suitable joining method such as adhesive, welding or screws. Thus, the support member 5 is erected on the upper surface of the fixed member 21 (the surface opposite to the movable member 22) in a non-tilting state.

[0064] On the other hand, the upper end of the support member 5, i.e., the end on the movable member 22 side, is connected to the movable member 22 via a first joint portion 51 with two or more degrees of freedom. In this embodiment, as an example, the first joint portion 51 has three degrees of freedom. That is, relative to the movable member 22, the support member 5 uses a three-degree-of-freedom first joint portion 51 to be connected to the lower surface (the surface opposite to the fixed member 21) of the movable member 22 in a tilting (rotational) state with two or more degrees of freedom.

[0065] In particular, in this embodiment, the first connector 51 is a magnetic ball connector that uses the magnetic force of a permanent magnet for magnetic bonding. Specifically, as... Figure 3 and Figure 4 As shown, the first connector portion 51 includes a spherical portion 511 made of a magnetic material and a base portion 512 containing a permanent magnet. The spherical portion 511 is attracted to the base portion 512 by magnetic force through its insertion into a spherical recess 513 in the base portion 512. Thus, the spherical portion 511 is supported in a state where it can rotate relative to the base portion 512 with three degrees of freedom.

[0066] In this embodiment, the ball portion 511 is fixed to the movable member 22 by a suitable joining method such as bonding, welding, or screws, and the base portion 512 is fixed to one end face (upper end face) of the support member 5 by a suitable joining method such as bonding, welding, or screws. Alternatively, the relationship between the ball portion 511 and the base portion 512 can be reversed; the base portion 512 can be fixed to the movable member 22, and the ball portion 511 can be fixed to the support member 5.

[0067] As an example, each of the pair of drive units 3 and 4 is formed as a generally cylindrical shape with a length in the vertical direction D3. Each drive unit 3 and 4 only needs to be able to extend and retract in the length direction (vertical direction D3). In this embodiment, each drive unit 3 and 4 is an electrically driven type that receives power supply to extend and retract, and can be implemented, for example, by a suitable mechanism such as a linear motor, voice coil, or rack and pinion.

[0068] Here, a pair of drive units 3 and 4 are arranged side by side in the left-right direction D1. In this embodiment, as an example, drive unit 3 is located on the left and drive unit 4 is located on the right.

[0069] A pair of drive units 3 and 4 mechanically connect the two vertices of the fixed member 21 and a pair of connection points set at equal distances from the center of the movable member 22. The pair of drive units 3 and 4 and the support member 5 are arranged in a roughly triangular shape such that they are not aligned in a straight line when viewed from above.

[0070] Specifically, such as Figure 5 As shown, when viewed from above, the pair of drive units 3 and 4 are arranged at a 120-degree interval along the circumference of an imaginary circle with the support member 5 as its vertex. That is, the pair of drive units 3 and 4 and the support member 5 are arranged in an isosceles triangle shape with a vertex angle of 120 degrees when viewed from above. Thus, the pair of drive units 3 and 4 are located within a sector-shaped region R1 with a vertex angle of less than 180 degrees with the support member 5 as its vertex.

[0071] The lower ends of a pair of drive units 3 and 4, i.e., the ends on the side of the fixed member 21, are respectively connected to the fixed member 21 via joints 31 and 41 with one degree of freedom. That is, relative to the fixed member 21, each drive unit 3 and 4 is connected to the upper surface (the surface opposite to the movable member 22) of the fixed member 21 in a tilting (rotating) state with one degree of freedom.

[0072] In particular, in this embodiment, each joint portion 31, 41 is a hinge structure capable of rotating around a pivot point. Specifically, as... Figure 3 and Figure 4 As shown, when viewed from above, each joint 31 and 41 can tilt each drive part 3 and 4 toward the center (support part 5) of the fixed part 21.

[0073] The upper ends of the pair of drive units 3 and 4, i.e., the ends on the movable member 22 side, are connected to the movable member 22 via second joints 32 and 42 with two or more degrees of freedom. In this embodiment, as an example, the second joints 32 and 42 have three degrees of freedom. That is, relative to the movable member 22, each drive unit 3 and 4 uses a three-degree-of-freedom second joint 32 and 42 to be connected to the lower surface (the surface opposite to the fixed member 21) of the movable member 22 in a tilting (rotational) state with two or more degrees of freedom.

[0074] In particular, in this embodiment, the second connector portions 32 and 42 are magnetic ball connectors that use the magnetic force of a permanent magnet for magnetic bonding. Specifically, as... Figure 3 and Figure 4 As shown, the second connector 32 of the drive unit 3 includes a spherical part 321 made of a magnetic material and a base part 322 containing a permanent magnet. The spherical part 321 is attracted to the base part 322 by magnetic force through its insertion into the spherical recess 323 of the base part 322. Thus, the spherical part 321 is supported in a state where it can rotate relative to the base part 322 with three degrees of freedom.

[0075] In this embodiment, the ball portion 321 is fixed to one end face (upper end face) of the drive portion 3 using a suitable joining method such as bonding, welding, or screws, and the base portion 322 is fixed to the movable member 22 using a suitable joining method such as bonding, welding, or screws. Alternatively, the relationship between the ball portion 321 and the base portion 322 can be reversed; that is, the base portion 322 can be fixed to the movable member 22, and the ball portion 321 can be fixed to the drive portion 3.

[0076] The second connector 42 of the drive unit 4 has the same structure as the second connector 32 of the drive unit 3. That is, the second connector 42 includes a spherical part 421 made of a magnetic material and a base part 422 containing a permanent magnet. The spherical part 421 is fixed to one end face (upper end face) of the drive unit 4 by a suitable joining method such as adhesive, welding or screws, and the base part 422 is fixed to the movable part 22 by a suitable joining method such as adhesive, welding or screws.

[0077] Here, the pair of drive units 3 and 4 can extend and retract independently. For example, drive unit 3 can extend while drive unit 4 retracts. Alternatively, both drive units 3 and 4 can extend or retract simultaneously.

[0078] Based on the structure described above, the movable member 22 can be driven relative to the fixed member 21 with at least two degrees of freedom via a pair of drive units 3 and 4. In this embodiment, since the movable member 22 is supported by the support member 5 via the first joint 51, it is driven to rotate around the first rotation axis Ax1 and the second rotation axis Ax2 with the first joint 51 as the fulcrum.

[0079] More precisely, since the first connector 51 is a (magnetic) ball connector, the movable part 22 rotates with two degrees of freedom, with the center of the sphere constituting the ball portion 511 in the first connector 51 as the fulcrum P1. That is, as Figure 5 As shown, the movable component 22 is driven to rotate by a pair of drive units 3 and 4 with two rotating axes (first rotating axis Ax1 and second rotating axis Ax2) that pass through the fulcrum P1 and intersect each other (orthogonal in this embodiment) as the center.

[0080] Specifically, such as Figure 6 As shown, by simultaneously extending and retracting a pair of drive units 3 and 4, the movable member 22 performs a pitching motion rotating around the first rotation axis Ax1. That is, by synchronously extending drive units 3 and 4 at the same length, the movable member 22 rotates around the first rotation axis Ax1. For example, by simultaneously retracting a pair of drive units 3 and 4, the movable member 22 moves along... Figure 6 The movable part 22 rotates counterclockwise, causing its front end to descend and its rear end to rise. Conversely, by simultaneously extending a pair of drive units 3 and 4, the movable part 22 moves along... Figure 6 The movable part 22 is rotated clockwise so that the front end of the movable part 22 rises and the rear end of the movable part 22 falls.

[0081] Furthermore, with the pitching motion of the movable part 22, when viewed from above, the engagement position of the pair of drive units 3 and 4 relative to the movable part 22 (i.e., the position of the second joints 32 and 42) changes. Therefore, with the pitching motion of the movable part 22, each drive unit 3 and 4 tilts relative to the fixed part 21 with each joint 31 and 41 as a fulcrum.

[0082] On the other hand, such as Figure 7 As shown, the movable member 22 performs a rolling motion around the second rotation axis Ax2 by extending and retracting a pair of drive parts 3 and 4 in such a way that the lengths of the drive parts 3 and 4 differ. That is, by extending the drive parts 3 and 4 to different lengths, the movable member 22 rotates around the second rotation axis Ax2. For example, by retracting the drive part 3 on the left while extending the drive part 4 on the right, the movable member 22 rolls along... Figure 7The movable part 22 rotates counterclockwise, causing the left end to descend and the right end to rise. Conversely, by extending the drive part 3 on the left while retracting the drive part 4 on the right, the movable part 22 moves along... Figure 7 Rotate clockwise to raise the left end of the movable part 22 and lower the right end of the movable part 22.

[0083] Furthermore, with the rolling motion of the movable part 22, when viewed from above, the engagement position of the pair of drive units 3 and 4 relative to the movable part 22 (i.e., the position of the second joint parts 32 and 42) changes. Therefore, with the rolling motion of the movable part 22, each drive unit 3 and 4 tilts relative to the fixed part 21 with each joint part 31 and 41 as a fulcrum.

[0084] Furthermore, by controlling the pair of drive units 3 and 4, a combined action of pitching and rolling can also be performed. That is, by simultaneously extending and retracting the pair of drive units 3 and 4, and by creating a difference in the amount of extension and retraction of the pair of drive units 3 and 4, the movable part 22 can perform a combined action of pitching and rolling.

[0085] For example, if, while both drive parts 3 and 4 retract, the retraction amount of drive part 3 is greater than that of drive part 4, then the movable part 22 will move along... Figure 6 While rotating counterclockwise (pitch motion), along Figure 7 It rotates counterclockwise (rolling action). Furthermore, if, while both drive units 3 and 4 are extended, the extension of drive unit 3 is greater than the extension of drive unit 4, then the movable part 22 rotates counterclockwise. Figure 6 While rotating clockwise (pitch motion), along Figure 7 Rotate clockwise (rolling motion).

[0086] As described above, based on the connection structure (joint) between the support member 5 and / or the pair of drive units 3, 4 relative to the fixed member 21 and the movable member 22, and the positional relationship between the support member 5 and the pair of drive units 3, 4, an actuator 1 with two or more degrees of freedom (two degrees of freedom in this embodiment) can be realized. That is, the actuator 1, under the control of the pair of drive units 3, 4, can drive the movable member 22 with two or more degrees of freedom (two degrees of freedom in this embodiment) while keeping the rotation center at a single point (fulcrum P1) even with only one pair (two) drive units 3, 4.

[0087] Furthermore, since the rotation center of the movable part 22 is fixed at the fulcrum P1, it is easier to calculate the positioning of the movable part 22, and the processing time involved in controlling the pair of drive units 3 and 4 that can be used to set the movable part 22 to the desired posture is relatively short.

[0088] Here, the movable area (movable range) of the movable part 22 in the actuator 1 is determined by the positional relationship between the fulcrum P1 (support member 5) and the pair of drive parts 3, 4, the movable (extension) range of each drive part 3, 4, the movable area (movable range) of the first joint part 51 and the second joint parts 32, 42, and the movable area (movable range) of the joint parts 31, 41, etc.

[0089] Furthermore, the load-bearing capacity (maximum tensile load) in actuator 1 is determined by the load-bearing capacity (maximum tensile load) of the first connector 51 and the second connectors 32 and 42. In this embodiment, the first connector 51 and the second connectors 32 and 42 are in particular magnetic ball connectors, so the load-bearing capacity (maximum tensile load) in actuator 1 can be increased according to the magnitude of the magnetic attraction of each magnetic ball connector. As an example, the load-bearing capacity (maximum tensile load) in actuator 1 is set to approximately 6 kg, 8 kg, or 10 kg.

[0090] Thus, the support member 5 has a first joint portion 51 with more than two degrees of freedom at at least one end in the longitudinal direction. In this embodiment, as an example, the support member 5 has a first joint portion 51 with more than two degrees of freedom at only one end (upper end) on the movable member 22 side in the longitudinal direction (vertical direction D3).

[0091] Therefore, although the movable part 22 can perform actions with more than two degrees of freedom, it is supported by the support part 5 relative to the fixed part 21. As a result, the load-bearing capacity (maximum tensile load) between the fixed part 21 and the movable part 22 can be improved.

[0092] Here, the first joint portion 51 is a magnetic ball joint. Therefore, the magnetic attraction of the first joint portion 51 can improve the load-bearing capacity (maximum tensile load) between the fixed member 21 and the movable member 22. In addition, compared with joints of two or more degrees of freedom other than magnetic ball joints such as universal joints or spherical bearings, the structure of the first joint portion 51 can be simplified, and a larger movable area (movable range) can be easily achieved.

[0093] Furthermore, each of the pair of drive units 3 and 4 has a second joint portion 32 or 42 with more than two degrees of freedom at at least one end in the longitudinal direction. In this embodiment, as an example, each of the pair of drive units 3 and 4 has a second joint portion 32 or 42 with more than two degrees of freedom at only one end (upper end) on the movable member 22 side in the longitudinal direction (vertical direction D3).

[0094] Therefore, although the movable part 22 can perform movements with more than two degrees of freedom, it is supported by a pair of drive parts 3 and 4 relative to the fixed part 21. As a result, the load-bearing capacity (maximum tensile load) between the fixed part 21 and the movable part 22 can be improved.

[0095] (3) Variations

[0096] Embodiment 1 is merely one of various reference examples of the present invention. Embodiment 1 can be modified in various ways, such as by design, to achieve the objectives of the present invention. Furthermore, the accompanying drawings referenced in this invention are schematic diagrams, and the size and thickness ratios of the structural elements shown do not necessarily reflect actual dimensional ratios. Hereinafter, variations of Embodiment 1 are listed. The variations described below can be appropriately combined and applied.

[0097] The support member 5 may have a first joint portion 51 with more than two degrees of freedom at at least one end in the length direction. For example, the support member 5 may also have a first joint portion 51 with more than two degrees of freedom at the end (lower end) of the fixed member 21 side in the length direction (vertical direction D3) or at both ends in the length direction.

[0098] In addition, each of the drive units 3 and 4 only needs to have a second connector 32 or 42 with more than two degrees of freedom at at least one end in the length direction. For example, each drive unit 3 and 4 may have a second connector 32 or 42 with more than two degrees of freedom at the end (lower end) of the fixed member 21 in the length direction (vertical direction D3) or at both ends in the length direction.

[0099] In addition, joints with two or more degrees of freedom, such as the first joint 51 and the second joints 32 and 42, are not limited to magnetic ball joints; for example, they can also be universal joints or spherical bearings.

[0100] In addition, as with joints 31 and 41, a joint with one degree of freedom is not limited to a hinge structure; for example, it can also be a deep groove ball bearing or an angular contact ball bearing.

[0101] Furthermore, the materials of the various structural elements of the actuator 1, such as the fixed part 21 and the movable part 22, are not limited to metal; for example, they can also be resins such as engineering plastics.

[0102] In addition, the support member 5 does not have to be a different part from the fixing member 21. The support member 5 and the fixing member 21 can also be integrated into one unit (an inseparable part).

[0103] Alternatively, lubricating oil or grease can be injected into the movable parts such as the first connector 51, the second connector 32, 42 and the connector 31, 41.

[0104] (Implementation Method 2)

[0105] like Figure 8As shown, the actuator 1A according to this embodiment differs from the actuator 1 according to Embodiment 1 in that the joint portions 31 and 41 at the lower ends of the pair of drive portions 3 and 4, i.e., the ends on the side of the fixed member 21, are "second joint portions" with two or more degrees of freedom. Hereinafter, the same reference numerals as in Embodiment 1 will be used for structural reference numerals and descriptions will be omitted as appropriate.

[0106] That is, each of the pair of drive units 3 and 4 has a second connector with two or more degrees of freedom at both ends in the longitudinal direction (vertical direction D3). In this embodiment, as an example, the connectors 31 and 41 are magnetic ball connectors that use the magnetic force of a permanent magnet for magnetic bonding. Therefore, there is no connector with one degree of freedom on the pair of drive units 3 and 4.

[0107] In the actuator 1A according to this embodiment, the movable member 22 is capable of rotating with "three degrees of freedom" around the fulcrum P1. That is, through a pair of drive units 3 and 4, the movable member 22 can rotate around the first rotation axis Ax1 (pitch action) and around the second rotation axis Ax2 (rolling action), and can also rotate around the third rotation axis Ax3.

[0108] The third rotation axis Ax3 is a straight line passing through the fulcrum P1 and intersecting (orthogonal in this embodiment) both the first rotation axis Ax1 and the second rotation axis Ax2, that is, a straight line along the vertical direction D3. Thus, the rotation centered on the third rotation axis Ax3 becomes a "yawing" action, and the third rotation axis Ax3 is the yawing axis.

[0109] Thus, in the actuator 1A according to this embodiment, a pair of drive units 3 and 4 drive the movable member 22 with three degrees of freedom relative to the fixed member 21, using the support member 5 as a fulcrum. Therefore, the actuator 1A can achieve a wider variety of actions.

[0110] In addition, the joints 31 and 32 with two or more degrees of freedom are not limited to magnetic ball joints, but can also be universal joints or spherical bearings, etc.

[0111] The structure of Embodiment 2 (including variations) can be used in appropriate combinations with the various structures (including variations) described in Embodiment 1.

[0112] (Implementation Method 3)

[0113] like Figure 9 As shown, the actuator 1B according to this embodiment differs from the actuator 1 according to Embodiment 1 in that it includes the driven cylinder 6. Hereinafter, the same reference numerals as in Embodiment 1 will be used for structural reference numerals, and descriptions will be omitted as appropriate.

[0114] Driven cylinder 6 is located in sector area R1 (see reference) Figure 5 The driven cylinder 6 mechanically connects the fixed member 21 and the movable member 22. The driven cylinder 6 is configured to be telescopic. In summary, in the actuator 1B according to this embodiment, in addition to the support member 5 and the pair of drive parts 3, 4, the fixed member 21 and the movable member 22 are connected by the driven cylinder 6. Therefore, compared with the case without the driven cylinder 6, the load-bearing capacity (maximum tensile load) between the fixed member 21 and the movable member 22 can be improved. Furthermore, compared with the case without the driven cylinder 6, an improvement in drive stability and impact resistance can also be expected.

[0115] Here, the driven cylinder 6 extends and retracts in tandem with the extension and retraction of a pair of drive units 3 and 4. That is, unlike the pair of drive units 3 and 4 that extend and retract actively, the driven cylinder 6 does not extend and retract actively on its own, but only passively extends and retracts through the extension and retraction of the pair of drive units 3 and 4. Therefore, no control is required for the driven cylinder 6, and simple control of the actuator 1B can be achieved.

[0116] More specifically, when viewed from above, the driven cylinder 6 and the pair of drive units 3 and 4 together form an equilateral triangle centered on the support member 5. That is, when viewed from above, the driven cylinder 6 and the pair of drive units 3 and 4 are arranged at a distance of 120 degrees in the circumference of an imaginary circle centered on the support member 5.

[0117] The lower end of the driven cylinder 6, i.e., the end on the side of the fixed component 21, is connected to the fixed component 21 via a third connector 61 with two or more degrees of freedom. In this embodiment, the third connector 61 is a three-degree-of-freedom magnetic ball connector that uses the magnetic force of a permanent magnet for magnetic connection.

[0118] Furthermore, the upper end of the driven cylinder 6, i.e., the end on the movable part 22 side, is connected to the movable part 22 via a third joint 62 with two or more degrees of freedom. In this embodiment, the third joint 62 is a three-degree-of-freedom magnetic ball joint that uses the magnetic force of a permanent magnet for magnetic connection.

[0119] Thus, the driven cylinder 6 has third joints 61 and 62 with more than two degrees of freedom at both ends in the length direction (vertical direction D3). Therefore, the driven cylinder 6 can be provided without restricting the movable area (movable range) of the movable part 22.

[0120] In this embodiment, since the joints 31 and 41 on the fixed member 21 side of the pair of drive units 3 and 4 are joints with one degree of freedom like a hinge structure, the movable member 22 is restricted to two degrees of freedom: pitching motion centered on the first rotation axis Ax1 and rolling motion centered on the second rotation axis Ax2.

[0121] In addition, the third joints 61 and 62 with two or more degrees of freedom are not limited to magnetic ball joints, but can also be universal joints or spherical bearings, etc.

[0122] The structure of Embodiment 3 (including variations) can be used in appropriate combinations with the various structures (including variations) described in Embodiment 1 or Embodiment 2.

[0123] (Implementation Method 4)

[0124] like Figure 10 As shown, the actuator 1C according to this embodiment differs from the actuator 1B according to embodiment 3 in that the joint portions 31 and 41 at the lower ends of the pair of drive portions 3 and 4, i.e., the ends on the side of the fixed member 21, are "second joint portions" with two or more degrees of freedom. Hereinafter, the same reference numerals as those in embodiment 3 will be used for structural reference numerals and descriptions will be omitted as appropriate.

[0125] That is, each of the pair of drive units 3 and 4 has a second joint with two or more degrees of freedom at both ends in the longitudinal direction (vertical direction D3). In this embodiment, as an example, the joints 31 and 41 are magnetic ball joints that use the magnetic force of a permanent magnet for magnetic bonding. Thus, there are no joints with one degree of freedom on the pair of drive units 3 and 4 or on the driven cylinder 6.

[0126] In the actuator 1C according to this embodiment, similarly to embodiment 2, the movable member 22 is capable of rotating with a "three-degree-of-freedom" motion centered on the fulcrum P1. That is, through a pair of drive units 3 and 4, the movable member 22 can not only rotate (pitch) centered on the first rotation axis Ax1 and rotate (roll) centered on the second rotation axis Ax2, but also rotate (yaw) centered on the third rotation axis Ax3.

[0127] In addition, the joints 31 and 32 with two or more degrees of freedom are not limited to magnetic ball joints, but can also be universal joints or spherical bearings, etc.

[0128] The structure of Embodiment 4 (including variations) can be appropriately combined with the various structures (including variations) described in Embodiment 1, Embodiment 2 or Embodiment 3.

[0129] (Implementation Method 5)

[0130] like Figure 11 As shown, the actuator 1D according to this embodiment differs from the actuator 1C according to embodiment 4 in that the lower end of the driven cylinder 6, i.e., the end on the side of the fixed member 21, is a joint portion 61 with one degree of freedom. Hereinafter, the same reference numerals as in embodiment 4 will be used for structural reference numerals and descriptions will be omitted as appropriate.

[0131] In this embodiment, as an example, the joint 61 of the driven cylinder 6 is a hinge structure. In this embodiment, since the joint 61 on the fixed part 21 side of the driven cylinder 6 is a one-degree-of-freedom joint like a hinge structure, the movable part 22 is restricted to two degrees of freedom, namely pitching motion centered on the first rotation axis Ax1 and rolling motion centered on the second rotation axis Ax2.

[0132] The structure of Embodiment 5 (including variations) can be used in appropriate combinations with the various structures (including variations) described in Embodiments 1, 2, 3 or 4.

[0133] As described above, the actuators (1, 1A, 1B, 1C, 1D) involved in the first embodiment include a fixed component (21), a movable component (22), a support component (5), and a pair of drive units (3, 4). The support component (5) mechanically connects the fixed component (21) and the movable component (22). The pair of drive units (3, 4) mechanically connect the fixed component (21) and the movable component (22), and are capable of extension and retraction respectively. The pair of drive units (3, 4) are located in a sector-shaped region (R1) with a vertex angle of less than 180 degrees with the support component (5) as the fulcrum. The pair of drive units (3, 4) drive the movable component (22) with at least two degrees of freedom relative to the fixed component (21), using the support component (5) as the fulcrum.

[0134] According to this method, by means of a pair of drive units (3, 4) located in a sector-shaped region (R1) with a vertex angle of less than 180 degrees with the support member (5) as the fulcrum, the movable member (22) can be driven with at least two degrees of freedom relative to the fixed member (21) with the support member (5) as the fulcrum. Thus, two degrees of freedom can be achieved by means of a pair (two) drive units (3, 4), which has the advantage of easy simplification of structure and control compared to a structure that requires three drive units.

[0135] In the actuators (1, 1A, 1B, 1C, 1D) involved in the second approach, in the first approach, the support member (5) has a first joint portion (51) with more than two degrees of freedom at at least one end in the length direction.

[0136] According to this method, although the movable part (22) can perform more than two degrees of freedom, it is supported by the support part (5) relative to the fixed part (21). Therefore, the load-bearing capacity (maximum tensile load) between the fixed part (21) and the movable part (22) can be improved.

[0137] In the actuators (1, 1A, 1B, 1C, 1D) involved in the third method, in the second method, the first connector (51) is a magnetic ball connector.

[0138] According to this method, the magnetic attraction of the first joint (51) can improve the load-bearing capacity (maximum tensile load) between the fixed part (21) and the movable part (22). In addition, compared with joints with two or more degrees of freedom other than universal joints or magnetic ball joints such as spherical bearings, the structure of the first joint (51) can be simplified, and a larger movable area (movable range) can be easily achieved.

[0139] In the actuators (1, 1A, 1B, 1C, 1D) involved in the fourth method, in any of the first to third methods, each of the pair of drive parts (3, 4) has a second joint part (32, 42) with more than two degrees of freedom at at least one end in the length direction.

[0140] According to this method, although the movable part (22) can perform actions with more than two degrees of freedom, it is supported by a pair of drive units (3, 4) relative to the fixed part (21). Therefore, the load-bearing capacity (maximum tensile load) between the fixed part (21) and the movable part (22) can be improved.

[0141] In the actuators (1, 1A, 1B, 1C, 1D) involved in the fifth method, in any of the first to fourth methods, a driven cylinder (6) is further included, which is disposed on the outside of the sector area (R1) and mechanically connects the fixed part (21) and the movable part (22) and is capable of extension and retraction.

[0142] According to this method, compared with the case without the driven cylinder (6), the load-bearing capacity (maximum tensile load) between the fixed part (21) and the movable part (22) can be improved. Furthermore, compared with the case without the driven cylinder (6), improved drive stability and impact resistance can also be expected.

[0143] In the actuators (1, 1A, 1B, 1C, 1D) involved in the sixth method, in the fifth method, the driven cylinder (6) has a third joint (61, 62) with more than two degrees of freedom at both ends in the length direction.

[0144] According to this method, a driven cylinder (6) can be installed while avoiding restrictions on the movable area (movable range) of the movable part (22).

[0145] In the actuators (1, 1A, 1B, 1C, 1D) involved in the seventh method, in the fifth or sixth method, the driven cylinder (6) extends and retracts in conjunction with the extension and retraction of a pair of drive units (3, 4).

[0146] According to this method, no control is required for the driven cylinder (6), and simple control of the actuators (1, 1A, 1B, 1C, 1D) can be achieved.

[0147] In the actuators (1, 1A, 1B, 1C, 1D) involved in the eighth method, in any of the first to seventh methods, a pair of drive units (3, 4) drive the movable part (22) with three degrees of freedom relative to the fixed part (21) with the support member (5) as the fulcrum.

[0148] According to this method, the actuators (1, 1A, 1B, 1C, 1D) can perform a wider variety of actions.

[0149] The robot joint device (110) involved in the ninth embodiment includes: an actuator (1, 1A, 1B, 1C, 1D) involved in any of the first to eighth embodiments; a first component (111) fixed to a fixed component (21); and a second component (112) fixed to a movable component (22).

[0150] According to this method, two degrees of freedom can be achieved through a pair (two) drive units (3, 4), which has the advantage of simplifying the structure and control compared to the structure that requires three drive units.

[0151] The structures involved in the second to eighth methods are not necessary for the actuators (1, 1A, 1B, 1C, 1D) and can be appropriately omitted.

[0152] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention specification and drawings under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. An actuator, characterized in that, include: Fixed components; Movable parts; A support component mechanically connects the fixed component and the movable component; as well as A pair of drive units mechanically connect the fixed component and the movable component, and are capable of extension and retraction respectively. The pair of drive units are located in a fan-shaped area with an apex angle of less than 180 degrees with the support component as the vertex, and drive the movable component with at least two degrees of freedom relative to the fixed component with the support component as the fulcrum.

2. The actuator as claimed in claim 1, characterized in that, The support component has a first joint portion with more than two degrees of freedom at at least one end in the longitudinal direction.

3. The actuator as described in claim 2, characterized in that, The first connector is a magnetic ball connector.

4. The actuator as described in any one of claims 1 to 3, characterized in that, Each of the pair of drive units has a second joint with more than two degrees of freedom at at least one end in the length direction.

5. The actuator as described in any one of claims 1 to 3, characterized in that, The actuator also includes a driven cylinder, which is disposed on the outside of the sector area and mechanically connects the fixed component and the movable component, enabling it to extend and retract.

6. The actuator as claimed in claim 5, characterized in that, The driven cylinder has a third joint with more than two degrees of freedom at both ends in the longitudinal direction.

7. The actuator as claimed in claim 5, characterized in that, The driven cylinder extends and retracts in conjunction with the extension and retraction of the pair of drive units.

8. The actuator as claimed in any one of claims 1 to 3, characterized in that, The pair of drive units drive the movable part with three degrees of freedom relative to the fixed part, using the support member as a fulcrum.

9. A joint device for a robot, characterized in that, include: The actuator as described in any one of claims 1 to 3; The first component is fixed to the fixed component; as well as The second component is fixed to the movable component.

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