Multi-degree-of-freedom transmission device and robot

Abstract

The multi-degree-of-freedom transmission device (1) includes a first platform (10), a second platform (20), a fixed platform (30), a first branch chain (40), a second branch chain (50), and a transmission assembly (60). The first branch chain (40), the first platform (10), and the fixed platform (30) form a first multi-degree-of-freedom parallel mechanism having an output end (80). The second branch chain (50), the second platform (20), and the fixed platform (30) form a second multi-degree-of-freedom parallel mechanism having an input end (90). The structure of the second branch chain (50) is similar to that of the first branch chain (40), and the size of the second branch chain is scaled proportionally to the first branch chain (40). The transmission assembly (60) is configured to couple the output end (80) to the input end (90).

Description

[Technical Field]

[0001] The present invention relates to the technical field of transmissions, and in particular to multi-degree-of-freedom transmissions and robots. [Background technology]

[0002] Many industrial applications require increased output force and torque. For example, to achieve a product production process, force and torque amplification technologies and devices can be implemented to provide a relatively small force and torque at the input end. In the prior art, reduction gearboxes or torque converters are typically used to increase output force and torque. However, these methods are limited to only one spatial degree of freedom. Parallel robots are increasingly being used in industry to perform operations such as grasping and moving workpieces in three-dimensional space. However, existing parallel robots are unable to increase output force and torque in multiple degrees of freedom. Therefore, when grasping and moving a workpiece, sufficient force and torque must be applied to the stressed parts of the parallel robot to complete the operation, which undoubtedly limits the applications of parallel robots. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Chinese Patent Application Publication No. 104950797 [Patent Document 2] Chinese Patent Application Publication No. 101292935 [Patent Document 3] International Publication No. 2019 / 126919 Brochure Summary of the Invention [Problem to be solved by the invention]

[0004] Therefore, there is a need to provide a multi-degree of freedom transmission and robot that overcomes the prior art's inability to increase force and torque output in multiple degrees of freedom. [Means for solving the problem]

[0005] A multi-degree-of-freedom transmission device includes a first platform, a second platform, a fixed platform installed between the first platform and the second platform, a plurality of first branch chains, a plurality of second branch chains, and a plurality of transmission assemblies, wherein the plurality of first branch chains are arranged in an array between the first platform and the fixed platform, the plurality of first branch chains, the first platform, and the fixed platform constitute a first multi-degree-of-freedom parallel mechanism, and the plurality of second branch chains are arranged on the second platform. and the fixed platform, the plurality of second branch chains, the second platform, and the fixed platform constitute a second multi-degree-of-freedom parallel mechanism, the structure of the second branch chains is similar to that of the first branch chains, and the size of the second branch chain is enlarged or reduced proportionally to the size of the first branch chain, and the plurality of transmission assemblies are coupled between the plurality of first branch chains and the plurality of second branch chains, and are configured to couple an output end of the first multi-degree-of-freedom parallel mechanism to an input end of the second multi-degree-of-freedom parallel mechanism.

[0006] In one embodiment, the plurality of transmission assemblies couple an output end of the first multiple degree of freedom parallel mechanism to an input end of the second multiple degree of freedom parallel mechanism at a 1:1 speed ratio.

[0007] In one embodiment, the plurality of first branch chains include three first branch chains, the plurality of second branch chains include three second branch chains, the three first branch chains, the first platform, and the fixed platform constitute a first 3-RRRS parallel mechanism, and the three second branch chains, the second platform, and the fixed platform constitute a second 3-RRRS parallel mechanism.

[0008] In one embodiment, any of the plurality of first branch chains includes a first ball pair, a first rotating pair, a second rotating pair, and a third rotating pair connected in sequence, the first ball pair being connected to the first platform and the third rotating pair being connected to the fixed platform, the first rotating pair and the second rotating pair being the output end of the first multi-degree-of-freedom parallel mechanism, and any of the second branch chains includes a second ball pair, a fourth rotating pair, a fifth rotating pair, and a sixth rotating pair connected in sequence, the second ball pair being connected to the second platform and the fourth rotating pair being connected to the fixed platform, the fifth rotating pair and the sixth rotating pair being the input end of the second multi-degree-of-freedom parallel mechanism.

[0009] In one embodiment, any of the plurality of transmission assemblies includes a first bevel gear coupled to the first rotating pair, a second bevel gear coupled to the second rotating pair, a third bevel gear coupled to the fifth rotating pair, a fourth bevel gear coupled to the sixth rotating pair, and a linkage assembly configured to transmit rotation of the first bevel gear to the third bevel gear and to transmit rotation of the second bevel gear to the fourth bevel gear.

[0010] In one embodiment, the linkage assembly includes a first group of transmission shafts rotatably connected to the fixed platform, a second group of transmission shafts, and a third group of transmission shafts, each of the first group of transmission shafts, the second group of transmission shafts, and the third group of transmission shafts includes a first shaft and a second shaft rotatably accommodated in the first shaft, both ends of the first group of transmission shafts are located on both sides of the fixed platform, the second group of transmission shafts and the third group of transmission shafts are located on one side of the fixed platform, the first group of transmission shafts and the third group of transmission shafts are perpendicularly connected to both ends of the second group of transmission shafts, a fifth bevel gear is respectively provided on both ends of each of the second shafts, and a sixth bevel gear is respectively provided on both ends of each of the first shafts, The fifth bevel gear and the sixth bevel gear located at the end of the first group of transmission shafts adjacent to the first branch chain mesh with the first bevel gear and the second bevel gear, respectively; the fifth bevel gear and the sixth bevel gear located at the end of the third group of transmission shafts adjacent to the second branch chain mesh with the third bevel gear and the fourth bevel gear, respectively; and the fifth bevel gear and the sixth bevel gear located at both ends of the second group of transmission shafts mesh with the fifth bevel gear and the sixth bevel gear located at the end of the first group of transmission shafts remote from the first branch chain, and mesh with the fifth bevel gear and the sixth bevel gear located at the end of the third group of transmission shafts remote from the second branch chain, respectively.

[0011] In one embodiment, the fixed platform further includes a plurality of support plates fixed to the side surfaces of the fixed platform on which the second group of transmission shafts and the third group of transmission shafts are positioned, each of the plurality of support plates having a group of support holes, and each of the second group of transmission shafts is rotatably received in the group of support holes.

[0012] In one embodiment, the fixed platform includes a fixed plate, three first connecting frames, and three second connecting frames, the fixed plate including a central portion and three positioning portions equally spaced around the central portion, the three first connecting frames are respectively fixed to ends of the three positioning portions away from the central portion and positioned on the side of the fixed plate facing the first platform, and the three second connecting frames are respectively fixed to ends of the three positioning portions adjacent to the central portion and positioned on the side of the fixed plate facing the second platform.

[0013] In one embodiment, a first through hole is provided at the end of each positioning portion away from the central portion, the first connecting frame includes two first fixed pieces fixed vertically to the fixed plate and a first pressure-bearing piece vertically connected between the two first fixed pieces, the first pressure-bearing piece has a first positioning hole provided therein corresponding to the first through hole, and a part of the transmission assembly is rotatably accommodated in the first through hole and the first positioning hole.

[0014] A robot includes the above multi-degree-of-freedom transmission device, wherein the first platform is a force input platform and the second platform is a force output platform.

[0015] In the multi-degree-of-freedom transmission device and robot disclosed herein, when the platform connected to the larger of the first and second branch chains functions as a force input platform, the force and / or torque received by the force input platform is transmitted to the force output platform connected to the smaller of the first and second branch chains via two multi-degree-of-freedom parallel mechanisms disposed on both sides of the fixed platform, thereby increasing the force and / or torque in multiple degrees of freedom output to the platform connected to the smaller branch chain and decreasing the displacement output to that platform.On the other hand, when the platform connected to the smaller of the first and second branch chains functions as a force input platform, the force and / or torque received by the force input platform is transmitted to the force output platform connected to the larger of the first and second branch chains via two multi-degree-of-freedom parallel mechanisms disposed on both sides of the fixed platform, thereby decreasing the force and / or torque in multiple degrees of freedom output to the platform connected to the larger branch chain and increasing the displacement output to that platform. In this way, the output multi-degree-of-freedom force / torque can be increased or decreased, or the output multi-degree-of-freedom displacement can be increased or decreased, as required.

[0016] These and other goals, advantages, objectives and features of the present disclosure will become apparent from the description and accompanying drawings of this specification.

[0017] Hereinafter, technical means according to embodiments of the present invention or conventional techniques will be described with reference to the drawings. Note that the accompanying drawings in the following description only show a part of the embodiments of the present invention, and it is clear that a person skilled in the art can conceive of other drawings from the accompanying drawings. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a perspective view of a multi-degree-of-freedom transmission according to one embodiment of the present disclosure;

[0019] [Figure 2] FIG. 2 is a front view of the multi-degree-of-freedom transmission device shown in FIG.

[0020] [Figure 3] 1 is a perspective view of a first branch chain, a transmission assembly, and a second branch chain according to one embodiment of the present disclosure.

[0021] [Figure 4] 4 is a front view of the first branch chain, the transmission assembly, and the second branch chain shown in FIG. 3.

[0022] [Figure 5] FIG. 2 is a perspective view of a first linkage assembly according to one embodiment of the present disclosure.

[0023] [Figure 6] FIG. 2 is a perspective view of a first transmission shaft group according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0024] To clarify the objectives, technical aspects, and advantages of the present disclosure, the present disclosure will now be described in detail with reference to the accompanying drawings and examples. It should be understood that the specific examples described herein are merely illustrative of the present disclosure and are not intended to limit the present disclosure. The components of the embodiments of the present invention, as generally described and illustrated in the drawings herein, could be arranged and designed in a wide variety of different configurations.

[0025] Therefore, the detailed description of the embodiments of the present disclosure provided in the accompanying drawings below is not intended to limit the scope of protection of the present disclosure, but merely illustrates preferred embodiments of the present disclosure. All other embodiments that can be obtained by those skilled in the art based on the embodiments of the present disclosure without any creative work also fall within the scope of protection of the present disclosure.

[0026] Note that in the following figures, like reference numerals refer to like items, so once an item is defined in one figure, no further definition or explanation is required in subsequent figures.

[0027] In describing the embodiments of the present disclosure, terms such as "center," "top," "bottom," "left," "right," "vertical," "horizontal," "inside," and "outside" are used for the convenience and simplification of the description of the present disclosure and do not expressly or imply that the referenced devices or elements must operate in a particular orientation, but indicate orientations and positional relationships based on the orientations and positional relationships shown in the drawings, orientations and positional relationships in which the product is normally placed when in use, or orientations and positional relationships that are normally understood by those skilled in the art, and are not intended to limit the present disclosure.

[0028] Furthermore, terms such as "first", "second", etc. are used merely to distinguish between descriptions and should not be construed to express or imply any relative importance.

[0029] The inventions in this disclosure will now be described in conjunction with the accompanying drawings.

[0030] 1-2, according to one embodiment, there is provided a multi-degree-of-freedom transmission device configured to transmit force and torque in multiple directions. The multi-degree-of-freedom transmission device 1 includes a first platform 10, a second platform 20, a fixed platform 30, a plurality of first branch chains 40, a plurality of second branch chains 50, and a plurality of transmission assemblies 60.

[0031] The first platform 10 and the second platform 20 are movable platforms. One of the first platform 10 and the second platform 20 is a platform that receives an external load, i.e., a force input platform, and the other is a platform that outputs a force, i.e., a force output platform. The fixed platform 30 is located between the first platform 10 and the second platform 20 and is fixedly installed, for example, fixed to a processing machine (not shown) or to a bracket fixed to the ground.

[0032] The plurality of first branch chains 40 are arranged in an array between the first platform 10 and the fixed platform 30. The plurality of first branch chains 40, the first platform 10, and the fixed platform 30 constitute a first multi-degree-of-freedom parallel mechanism, allowing the first platform 10 to receive or output forces and torques in multiple directions.

[0033] The multiple second branch chains 50 are arranged in an array between the second platform 20 and the fixed platform 30. The multiple second branch chains 50, the second platform 20, and the fixed platform 30 constitute a second multi-degree-of-freedom parallel mechanism, allowing the second platform 20 to receive or output multi-directional forces and torques. The fixed platform 30 may be a platform shared by the first and second multi-degree-of-freedom parallel mechanisms. Alternatively, the fixed platform 30 may be formed by connecting a stationary platform of the first multi-degree-of-freedom parallel mechanism to a stationary platform of the second multi-degree-of-freedom parallel mechanism. The structure of the second branch chain 50 is similar to that of the first branch chain 40, and the size of the second branch chain 50 is proportional to or smaller than that of the first branch chain 40. Specifically, the arrangement of the multiple second branch chains 50 relative to the fixed platform 30 is essentially the same as the arrangement of the multiple first branch chains 40 relative to the fixed platform 30. The components of the second branch chain 50 and their connection order are essentially the same as the components of the first branch chain 40, except that the size of the components of the second branch chain 50 is enlarged or reduced proportionally to the size of the components of the first branch chain 40.

[0034] The plurality of transmission assemblies 60 are coupled between the plurality of first branch chains 40 and the plurality of second branch chains 50, and are configured to couple an output end 80 (see FIG. 3) of the first multi-degree-of-freedom parallel mechanism to an input end 90 (see FIG. 3) of the second multi-degree-of-freedom parallel mechanism. In one embodiment, the plurality of transmission assemblies 60 couple the output end 80 of the first multi-degree-of-freedom parallel mechanism to the input end 90 of the second multi-degree-of-freedom parallel mechanism at a speed ratio of 1:1. In this embodiment, the force, torque, and / or displacement output by the output end 80 of the first multi-degree-of-freedom parallel mechanism is the same as the force, torque, and / or displacement acquired by the input end 90 of the second multi-degree-of-freedom parallel mechanism, so that the rotation angle of the output end 80 of the first multi-degree-of-freedom parallel mechanism is the same as the rotation angle of the input end 90 of the second multi-degree-of-freedom parallel mechanism. When an external force received by the first platform 10 or the second platform 20 as a force input platform is transmitted to the second platform 20 or the first platform 10 as a force output platform, the magnitude of the force and / or torque and displacement in multiple spatial degrees of freedom output by the force output platform can be adjusted by the proportionality of the sizes of the first branch chain 40 and the second branch chain 50.

[0035] Since the multi-degree-of-freedom transmission device 1 includes two multi-degree-of-freedom parallel mechanisms located on both sides of the fixed platform 30, a force and / or torque in any direction applied to the first platform 10 (in this case, the first platform 10 functions as a force input platform) is transmitted to the transmission assembly 60 via the first branch chain 40, then to the second branch chain 50 via the transmission assembly 60, and finally to the second platform 20 via the second branch chain 50 (in this case, the second platform 20 functions as a force output platform). In this way, the multi-degree-of-freedom force and / or torque at the first platform 10 is transmitted to the execution terminal of the second platform 20, and the multi-degree-of-freedom displacement at the first platform 10 is transmitted to the execution terminal of the second platform 20.

[0036] Since the first platform 10 and the second platform 20 are movable platforms and the fixed platform 30 is a fixed platform, the first branch chain 40 and the second branch chain 50 correspond to the force arms of the levers on both sides of the support point. Furthermore, since the size of the components of the second branch chain 50 increases or decreases in the same predetermined proportion to the size of the corresponding components of the first branch chain 40, when the force and / or torque received by the first platform 10 is transmitted through the multi-degree-of-freedom transmission device 1, a reduced or increased force and / or torque is obtained on the second platform 20, thereby decreasing or increasing the force and / or torque applied to the execution terminal of the second platform 20. It should be noted that in another embodiment, the second platform 20 can be configured to receive torque and the first platform 10 to output torque, i.e., the second platform 20 functions as a force input platform and the first platform 10 functions as a force output platform. When the device is configured to increase the force and / or torque, a preset operation that needs to be performed by the execution terminal of the force output platform, such as an operation to grip a workpiece, can be achieved by applying a small force and / or torque to the force input platform, making it easy to grip the workpiece. When the device is configured to reduce the force and / or torque, it is possible to prevent the execution target of the execution terminal of the force output platform from being damaged by a large force and / or torque.

[0037] In the embodiment shown in FIG. 1 , the size of each component of the second branch chain 50 is reduced in proportion to the size of the corresponding component of the first branch chain 40 in a 2:1 ratio. When the first platform 10 is used as a force input platform and the second platform 20 is used as a force output platform, it is possible to obtain an increased force and / or torque and a decreased displacement on the second platform 20. In this manner, a function of increasing the output force / torque and a function of decreasing the displacement on multiple spatial degrees of freedom from the first platform 10 to the second platform 20 are realized. When the second platform 20 is used as a force input platform and the first platform 10 is used as a force output platform, it is possible to obtain a decreased force and / or torque and an increased displacement on the first platform 10. In this manner, a function of decreasing the output force / torque and a function of increasing the displacement on multiple spatial degrees of freedom from the second platform 20 to the first platform 10 are realized.

[0038] In one embodiment, as shown in FIGS. 1 and 4 , the fixed platform 30 is generally Y-shaped. The fixed platform 30 includes a fixed plate 31, three first connecting frames 32, and three second connecting frames 33. The fixed plate 31 includes a central portion 311 and three positioning portions 312 connected to the central portion 311. The three positioning portions 312 extend outward from the central portion 311 at equal intervals, with the angle between two adjacent positioning portions 312 being approximately 120°. A first through-hole 313 is provided at the end of each positioning portion 312 away from the central portion 311. Each of the three first connecting frames 32 is fixed to the end of the three positioning portions 312 away from the central portion 311. In this embodiment, the three first connecting frames 32 are located on the side of the fixed plate 31 facing the first platform 10. The first connecting frame 32 includes two first fixed pieces 321 fixed vertically to the fixed plate 31 and a first pressure-receiving piece 322 vertically connected between the two first fixed pieces 321. The first pressure-receiving piece 322 has a first positioning hole 323 corresponding to the first through-hole 313, and a portion of the transmission assembly 60 is rotatably received in the first through-hole 313 and the first positioning hole 323. The three second connecting frames 33 are fixed to ends adjacent to the center portion 311 of the three positioning portions 312, respectively, and are located on the side of the fixed plate 31 facing the second platform 20. The structure of the second connecting frame 33 is similar to that of the first connecting frame 32, and includes two second fixed pieces 331 fixed vertically to the fixed plate 31 and a second pressure-receiving piece 332 vertically connected between the two second fixed pieces 331. The second pressure piece 332 is provided with a second positioning hole 333 for rotatably receiving other parts of the transmission assembly 60 .

[0039] In some embodiments, the number of first branch chains 40 is three, and the number of second branch chains 50 is also three. The three first branch chains 40 are evenly spaced between the first platform 10 and the three first connecting frames 32 and connected to one end of three transmission assemblies 60, so that movement can be transmitted between the transmission assemblies 60 and the first branch chains 40. In some embodiments, the three first branch chains 40, the first platform 10, and the fixed platform 30 constitute a first 3-RRRS parallel mechanism (RRRS means a kinematic pair consisting of three rotating pairs (R) and one spherical pair (S)). The three second branch chains 50 are evenly spaced between the second platform 20 and the three second connecting frames 33 and connected to the other end of the transmission assemblies 60, so that movement can be transmitted between the second branch chains 50 and the transmission assemblies 60. The three second branch chains 50, the second platform 20, and the fixed platform 30 constitute a second 3-RRRS parallel mechanism. For definitions of a 3-RRRS parallel mechanism, reference may be made to prior art documents such as Patent Documents 1, 2, and 3, the entire contents of which are incorporated herein by reference. The movable platform of the 3-RRRS parallel mechanism has six spatial degrees of freedom. Since the two movable platforms of the two 3-RRRS parallel mechanisms are used as the input and output platforms of the multi-degree-of-freedom transmission device 1, respectively, six spatial degrees of freedom of movement can be transmitted from the first platform 10 to the second platform 20. It should be understood that the first branch chain 40 and the second branch chain 50 are merely one example of a six-degree-of-freedom parallel mechanism. In other embodiments, the structures of the first branch chain 40 and the second branch chain 50 may be other six-degree-of-freedom parallel mechanisms. The first branch chain 40 and the second branch chain 50 may also be other multi-degree-of-freedom parallel mechanisms, for example, three-degree-of-freedom parallel mechanisms that can achieve three degrees of freedom of spatial movement between the first platform 10 and the second platform 20.

[0040] 1 , in some embodiments, the first branch chain 40 includes a first ball pair 41, a first rotating pair 44, a second rotating pair 45, and a third rotating pair 46, which are connected in sequence. The first ball pair 41 is connected to the first platform 10, and the third rotating pair 46 is connected to the fixed platform 30. The first rotating pair 44 and the second rotating pair 45 are the output end 80 of the first multiple-degree-of-freedom parallel mechanism and are connected to one end of the transmission assembly 60. The first rotating pair 44 and the second rotating pair 45 are connected to the first ball pair 41, and the rotation axis of the first rotating pair 44 is parallel to or coincides with the rotation axis of the second rotating pair 45. The third rotating pair 46 is rotatably coupled to the first rotating pair 44 and the second rotating pair 45, and the rotation axis of the third rotating pair 46 is perpendicular to the rotation axes of the first rotating pair 44 and the second rotating pair 45. When the first platform 10 receives a force and / or torque as a force input platform, the force and / or torque is transmitted to the first rotating pair 44 and the second rotating pair 45 via the first ball pair 41, then to the transmission assembly 60 coupled to the first rotating pair 44 and the second rotating pair 45, and further transmitted to the second platform 20 via the transmission assembly 60 and the second branch chain 50. When movement is transmitted to the transmission assembly 60 by the first rotating pair 44 and the second rotating pair 45, the rotation of the first rotating pair 44 and the second rotating pair 45 relative to the fixed platform 30 can be achieved via the third rotating pair 46, thereby avoiding distortion of the first rotating pair 44 and the second rotating pair 45 during rotation.

[0041] 5 , the first ball pair 41 includes a cross shaft universal joint 411, a first rotating rod 412 connected to one end of the cross shaft universal joint 411, a second rotating rod 413 connected to the other end of the cross shaft universal joint 411, and a first linkage assembly 414. The first rotating rod 412 is rotatably connected to the first platform 10, and the second rotating rod 413 is rotatably connected to the first linkage assembly 414. In this embodiment, the first platform 10 is generally circular, and the three fixing blocks 417 are fixed to the edges of the first platform 10. A first bearing 418 is installed in each fixed block 417, and one end of the first rotating rod 412 remote from the second rotating rod 413 is rotatably received in the first bearing 418, thereby realizing a rotational connection between the first rotating rod 412 and the first platform 10. The rotation axis of the first rotating rod 412 is the central axis of the first rotating rod 412. The first linkage assembly 414 includes two first connecting rods 415. A second bearing 425 is fixed between the two first connecting rods 421, and the second rotating rod 413 is rotatably connected to the second bearing 416, thereby realizing a rotational connection between the second rotating rod 413 and the first linkage assembly 42. The rotation axis of the second rotating rod 413 is the central axis of the second rotating rod 413.

[0042] 3 , the first rotating pair 44 includes a second connecting rod 441, a third connecting rod 442, and a first rotating shaft 443. One end of the second connecting rod 441 is rotatably connected to the two first connecting rods 415 of the first linkage assembly 414 and the other end of the second connecting rod 441 is fixed to one end of the third connecting rod 442 and is fixedly connected to one end of the third connecting rod 442 that is remote from the second connecting rod 441, and is rotatably connected to the third rotating pair 46. The first rotating shaft 443 and the second connecting rod 441 are located on the same side of the third connecting rod 442.

[0043] The second rotating pair 45 includes a fourth connecting rod 451, a fifth connecting rod 452, a sixth connecting rod 453, and a second rotating shaft 454. One end of the fourth connecting rod 451 is rotatably connected to the two first connecting rods 415 of the first linkage assembly 414 and is located farther from the second rotating rod 413 than the second connecting rod 441. The other end of the fourth connecting rod 451 is fixed perpendicularly to one end of the fifth connecting rod 452, and the other end of the fifth connecting rod 452 is rotatably connected to one end of the sixth connecting rod 453. The sixth connecting rod 453 and the fourth connecting rod 451 are located on the same side of the fifth connecting rod 452. The second rotating shaft 454 is fixedly connected to the other end of the sixth connecting rod 453 and rotatably connected to the third rotating pair 46 .

[0044] The third rotating pair 46 includes a first bracket 461 and a third rotating shaft 462. The first rotating shaft 443 and the second rotating shaft 454 are rotatably coupled to the first bracket 461. The third rotating shaft 462 is coupled to the first bracket 461 and rotatably coupled to the fixed platform 30, thereby realizing a rotational coupling between the third rotating pair 46 and the fixed platform 30.

[0045] 1 , the first bracket 461 includes two first vertical plates 463 arranged in parallel, a first horizontal plate 464 vertically connected between the two first vertical plates 463, and a third rotating shaft 462 connected to the first horizontal plate 464. The third connecting rod 442 and the sixth connecting rod 453 are located outside the two first vertical plates 463. Each first vertical plate 463 has a first horizontal hole 465 parallel to the fixed platform 30, and the first rotating shaft 443 and the second rotating shaft 454 rotatably extend through the first horizontal hole 465, respectively, to realize the rotational connection between the first rotating pair 44, the second rotating pair 45, and the third rotating pair 46. The first horizontal plate 464 has a first vertical hole 466 aligned with the first positioning hole 323, and a portion of the transmission assembly 60 is rotatably received in the first through hole 313, the first positioning hole 323, and the first vertical hole 466. In one embodiment, the third rotating shaft 462 has a limiting hole (not shown) coaxial with the first positioning hole 323 and the first vertical hole 466, and the transmission assembly 60 is rotatably received in the first through hole 313, the first positioning hole 323, the first vertical hole 466, and the limiting hole.

[0046] The second branch chain 50 includes a second ball pair 51, a fourth rotating pair 56, a fifth rotating pair 54, and a sixth rotating pair 55, which are connected in sequence. The second ball pair 51 is connected to the second platform 20, the fourth rotating pair 56 is connected to the fixed platform 30, and the fifth rotating pair 54 and the sixth rotating pair 55 are the input end 90 of the second multi-degree-of-freedom parallel mechanism and are connected to the other end of the transmission assembly 60. The structures and connection relationships of the second ball pair 51, the fourth rotating pair 56, the fifth rotating pair 54, and the sixth rotating pair 55 are similar to the structures and connection relationships of the first ball pair 41, the first rotating pair 44, and the second rotating pair, and will not be repeated here. The sizes of the second ball pair 51, the fourth rotating pair 56, the fifth rotating pair 54, and the sixth rotating pair 55 are enlarged or reduced proportionally to the sizes of the first ball pair 41, the first rotating pair 44, the second rotating pair 45, and the third rotating pair 46. The fourth rotating pair 56 is rotatably coupled to the second pressure-receiving piece 332 of the fixed platform 30. The fifth rotating pair 54 and the sixth rotating pair 55 are rotatably coupled to the fourth rotating pair, and the rotation axis of the fifth rotating pair 54 is parallel to or coincides with the rotation axis of the sixth rotating pair 55. The rotation axis of the fourth rotating pair 56 is perpendicular to the rotation axes of the fifth rotating pair 54 and the sixth rotating pair 55. When torque received by the first rotating pair 44 and the second rotating pair 45 is transmitted to the transmission assembly 60, the torque can be transmitted to the fifth rotating pair 54 and the sixth rotating pair 55 via the transmission assembly 60 and transmitted to the second platform 20 via the second ball pair 51. When torque received by the first rotating pair 44 and the second rotating pair 45 is transmitted to the fifth rotating pair 54 and the sixth rotating pair 55 via the transmission assembly 60, the fifth rotating pair 54 and the sixth rotating pair 55 can rotate relative to the fixed platform 30 via the fourth rotating pair 56, thereby avoiding distortion of the fifth rotating pair 54 and the sixth rotating pair 55.

[0047] The first and second multi-degree-of-freedom parallel mechanisms are not limited to the 3-RRRS parallel mechanism, but may be other parallel mechanisms capable of realizing a multi-degree-of-freedom parallel mechanism, such as a 3-URS parallel mechanism (URS means a branched chain motion pair consisting of one universal pair (U), one rotational pair (R), and one spherical pair (S)). For example, if the first and second multi-degree-of-freedom parallel mechanisms are both three-degree-of-freedom parallel mechanisms, the multi-degree-of-freedom transmission device 1 can transmit motion with three spatial degrees of freedom.

[0048] 2, 3, and 6, the transmission assembly 60 includes a first bevel gear 61 connected to the first rotating pair 44, a second bevel gear 62 connected to the second rotating pair 45, a third bevel gear 63 connected to the fifth rotating pair 54, a fourth bevel gear 64 connected to the sixth rotating pair 55, and a linkage assembly 65. The pitch diameter of the first bevel gear 61 is smaller than the pitch diameter of the second bevel gear 62, and the pitch diameter of the third bevel gear 63 is smaller than the pitch diameter of the fourth bevel gear 64. The linkage assembly 65 is configured to transmit the rotation of the first bevel gear 61 to the third bevel gear 63 and to transmit the rotation of the second bevel gear 62 to the fourth bevel gear 64.

[0049] The linkage assembly 65 includes a first group of transmission shafts 66, a second group of transmission shafts 67, and a third group of transmission shafts 68 that are rotatably connected to the fixed platform 30. The first group of transmission shafts 66 are rotatably received in the first through hole 313, the first positioning hole 323, and the first vertical hole 466, and both ends of the first group of transmission shafts 66 are located on opposite sides of the fixed platform 30. The second group of transmission shafts 67 and the third group of transmission shafts 68 are located on one side of the fixed platform 30, and the first group of transmission shafts 66 and the third group of transmission shafts 68 are vertically connected to both ends of the second group of transmission shafts 67. A plurality of support plates 34 are fixed to the side of the fixed platform 30 where the second group of transmission shafts 67 and the third group of transmission shafts 68 are located. Each support plate 34 is provided with a coaxial support hole group 35, the central axis of which is parallel to the fixed platform 30, and each second transmission shaft group 67 is rotatably received in the support hole group 35. The third transmission shaft group 68 is rotatably received in holes corresponding to the second positioning holes 333 and the first vertical holes 466 of the fourth rotating pair 56.

[0050] The first transmission shaft group 66, the second transmission shaft group 67, and the third transmission shaft group 68 each include a first shaft 69 and a second shaft 70 rotatably accommodated in the first shaft 69. A fifth bevel gear 71 is provided on each end of each second shaft 70, and a sixth bevel gear 72 is provided on each end of each first shaft 69. The fifth bevel gear 71 and the sixth bevel gear 72, located at the end of the first transmission shaft group 66 adjacent to the first branch chain 40, mesh with the first bevel gear 61 and the second bevel gear 62, respectively. The fifth bevel gear 71 and the sixth bevel gear 72, located at the end of the third transmission shaft group 68 adjacent to the second branch chain 40, mesh with the third bevel gear 63 and the fourth bevel gear 64, respectively. The fifth bevel gear 71 and the sixth bevel gear 72 located at both ends of the second transmission shaft group 67 mesh with the fifth bevel gear 71 and the sixth bevel gear 72 located at the end of the first transmission shaft group 66 remote from the first branch chain 40, and the fifth bevel gear 71 and the sixth bevel gear 72 located at the end of the third transmission shaft group 68 remote from the second branch chain 50, respectively. In this way, movement between the first bevel gear 61, the second bevel gear 62, the third bevel gear 63, and the fourth bevel gear 64 is transmitted via the fifth bevel gear 71 located at both ends of the second shaft 70 and the sixth bevel gear 72 located at both ends of the first shaft 69.

[0051] In one embodiment, the first bevel gear 61, the third bevel gear 63, and the fifth bevel gear 71 have the same structure and size, and the second bevel gear 62, the fourth bevel gear 64, and the sixth bevel gear have the same structure and size, so that the transmission assembly 60 transmits the torque of the output end 80 (first rotating pair 44 and second rotating pair 45) of the first multi-degree of freedom parallel mechanism to the input end 90 (fifth rotating pair 54 and sixth rotating pair 55) of the second multi-degree of freedom parallel mechanism at a speed ratio of 1:1.

[0052] The transmission assembly 66 is not limited to the above bevel gear transmission structure, but may be any other transmission mechanism, such as a worm gear transmission structure, as long as it is capable of transmitting motion between two parallel mechanisms with multiple degrees of freedom.

[0053] The present disclosure further provides a robot including the above-mentioned multi-degree-of-freedom transmission device 1. The first platform 10 is a force input platform and is used to receive an applied force and / or torque, and the second platform 20 is a force output platform and is configured to process or transport a product via an execution terminal on the force output platform.

[0054] According to the multi-degree-of-freedom transmission device 1 and the robot, when the platform connected to the larger of the first branch chain 40 and the second branch chain 50 functions as a force input platform, the force and / or torque received by the force input platform is transmitted to the force output platform connected to the smaller of the first branch chain 40 and the second branch chain 50 via the two multi-degree-of-freedom parallel mechanisms disposed on both sides of the fixed platform 30, thereby increasing the multi-degree-of-freedom force and / or torque output to the platform connected to the smaller branch chain and reducing the displacement output to that platform. When the platform connected to the smaller of the first branch chain 40 and the second branch chain 50 functions as a force input platform, the force and / or torque received by the force input platform is transmitted to the force output platform connected to the larger of the first branch chain 40 and the second branch chain 50 via the two multi-degree-of-freedom parallel mechanisms disposed on both sides of the fixed platform 30, thereby increasing the multi-degree-of-freedom force and / or torque output to the platform connected to the larger branch chain and reducing the displacement output to that platform. In this way, the output multi-degree-of-freedom force / torque or multi-degree-of-freedom displacement can be increased or decreased as needed.

[0055] The above description is merely a specific example of the present invention and does not limit the scope of protection of the present invention. Any modifications or replacements that are easily conceived by a person skilled in the art within the technical scope disclosed in the present invention shall fall within the scope of protection of the present invention.

[0056] The above embodiments do not limit the protection scope of the present invention. Modifications, equivalent replacements, and improvements made within the spirit and principle of the above embodiments shall also be included in the protection scope of the present invention.

Claims

1. A multi-degree-of-freedom transmission device, a first platform, a second platform, a fixed platform installed between the first platform and the second platform, a plurality of first branch chains, a plurality of second branch chains, and a plurality of transmission assemblies; the plurality of first branch chains are arranged in an array between the first platform and the fixed platform, and the plurality of first branch chains, the first platform, and the fixed platform constitute a first multi-degree-of-freedom parallel mechanism; the plurality of second branch chains are arranged in an array between the second platform and the fixed platform, the plurality of second branch chains, the second platform, and the fixed platform constitute a second multi-degree-of-freedom parallel mechanism, the structure of the second branch chains is similar to the structure of the first branch chain, and the size of the second branch chain is enlarged or reduced in proportion to the size of the first branch chain; the plurality of transmission assemblies are coupled between the plurality of first branch chains and the plurality of second branch chains, and are configured to couple an output end of the first multi-degree-of-freedom parallel mechanism to an input end of the second multi-degree-of-freedom parallel mechanism.

2. 2. The multi-degree-of-freedom transmission device according to claim 1, wherein the plurality of transmission assemblies couple an output end of the first multi-degree-of-freedom parallel mechanism to an input end of the second multi-degree-of-freedom parallel mechanism at a speed ratio of 1:

1.

3. 2. The multi-degree-of-freedom transmission device according to claim 1, wherein the plurality of first branch chains includes three first branch chains, the plurality of second branch chains includes three second branch chains, the three first branch chains, the first platform, and the fixed platform constitute a first 3-RRRS parallel mechanism, and the three second branch chains, the second platform, and the fixed platform constitute a second 3-RRRS parallel mechanism.

4. Each of the plurality of first branch chains includes a first ball pair, a first rotating pair, a second rotating pair, and a third rotating pair, which are connected in sequence; the first ball pair is coupled to the first platform, the third rotating pair is coupled to the fixed platform, and the first rotating pair and the second rotating pair are output ends of the first multi-degree-of-freedom parallel mechanism; Each of the second branch chains includes a second ball pair, a fourth rotating pair, a fifth rotating pair, and a sixth rotating pair connected in sequence, 4. The multi-degree-of-freedom transmission device of claim 3, wherein the second ball pair is coupled to the second platform, the fourth rotating pair is coupled to the fixed platform, and the fifth rotating pair and the sixth rotating pair are input ends of the second multi-degree-of-freedom parallel mechanism.

5. any one of the plurality of transmission assemblies includes a first bevel gear coupled to the first rotating pair, a second bevel gear coupled to the second rotating pair, a third bevel gear coupled to the fifth rotating pair, a fourth bevel gear coupled to the sixth rotating pair, and a linkage assembly; 5. The multiple degree of freedom transmission of claim 4, wherein the linkage assembly is configured to transmit rotation of the first bevel gear to the third bevel gear and to transmit rotation of the second bevel gear to the fourth bevel gear.

6. the linkage assembly includes first transmission shafts, second transmission shafts, and third transmission shafts rotatably coupled to the fixed platform; any of the first transmission shaft group, the second transmission shaft group, and the third transmission shaft group includes a first shaft and a second shaft rotatably accommodated in the first shaft; the first group of transmission shafts have opposite ends located on opposite sides of the fixed platform, the second group of transmission shafts and the third group of transmission shafts are located on one side of the fixed platform, and the first group of transmission shafts and the third group of transmission shafts are perpendicularly connected to the opposite ends of the second group of transmission shafts; A fifth bevel gear is provided on each end of each of the second shafts, and a sixth bevel gear is provided on each end of each of the first shafts, the fifth bevel gear and the sixth bevel gear located at the end of the first transmission shaft group adjacent to the first branch chain mesh with the first bevel gear and the second bevel gear, respectively; the fifth bevel gear and the sixth bevel gear located at the end of the third transmission shaft group adjacent to the second branch chain mesh with the third bevel gear and the fourth bevel gear, respectively; 6. The multi-degree-of-freedom transmission device according to claim 5, wherein the fifth bevel gear and the sixth bevel gear located at both ends of the second group of transmission shafts mesh with the fifth bevel gear and the sixth bevel gear located at an end of the first group of transmission shafts remote from the first branch chain, and mesh with the fifth bevel gear and the sixth bevel gear located at an end of the third group of transmission shafts remote from the second branch chain.

7. 7. The multi-degree-of-freedom transmission device according to claim 6, wherein the fixed platform further includes a plurality of support plates fixed to side surfaces of the fixed platform on which the second group of transmission shafts and the third group of transmission shafts are positioned, each of the plurality of support plates having a group of support holes, and each of the second group of transmission shafts is rotatably received in the group of support holes.

8. 4. The multi-degree-of-freedom transmission device according to claim 3, wherein the fixed platform includes a fixed plate, three first connecting frames, and three second connecting frames, the fixed plate including a central portion and three positioning portions equally spaced around the central portion, the three first connecting frames being fixed to ends of the three positioning portions away from the central portion, respectively, and being located on a side of the fixed plate facing the first platform, and the three second connecting frames being fixed to ends of the three positioning portions adjacent to the central portion, respectively, and being located on a side of the fixed plate facing the second platform.

9. 9. The multi-degree-of-freedom transmission device of claim 8, characterized in that a first through hole is provided at the end of each positioning portion away from the central portion, the first connecting frame includes two first fixed pieces fixed vertically to the fixed plate and a first pressure-bearing piece vertically connected between the two first fixed pieces, the first pressure-bearing piece has a first positioning hole provided corresponding to the first through hole, and a part of the transmission assembly is rotatably accommodated in the first through hole and the first positioning hole.

10. A robot, A robot comprising the multi-degree-of-freedom transmission device according to any one of claims 1 to 9, wherein the first platform is a force input platform and the second platform is a force output platform.

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