Multi-degree-of-freedom transmission devices and robots

Abstract

This invention discloses a multi-degree-of-freedom transmission device and robot, including a first platform, a second platform, a fixed platform disposed between the first and second platforms, multiple first branches, multiple second branches, and multiple transmission components. Multiple first branches are connected in parallel between the first platform and the fixed platform, forming a first multi-degree-of-freedom parallel mechanism. Multiple second branches are connected in parallel between the second platform and the fixed platform, forming a second multi-degree-of-freedom parallel mechanism. The structure of the second branches is similar to that of the first branches, and the size of the second branches is proportionally enlarged or reduced compared to the size of the first branches. Multiple transmission components are coupled between the first and second branches to couple the output end of the first multi-degree-of-freedom parallel mechanism to the input end of the second multi-degree-of-freedom parallel mechanism. The above-described multi-degree-of-freedom transmission device and robot can increase the output torque.

Description

Technical Field

[0001] This invention relates to the field of transmission technology, specifically to a multi-degree-of-freedom transmission device and robot. Background Technology

[0002] In many industrial scenarios, it is necessary to increase output force and torque. For example, in the product manufacturing process, increasing output force and torque allows for processing of the product by applying a smaller force and torque at the input end. Current technologies typically use gearboxes or torque converters to increase output force and torque; however, these methods are limited to only one degree of spatial freedom. Furthermore, parallel robots are increasingly used in industry for tasks such as grasping and moving materials in three-dimensional space. Existing parallel robots cannot achieve increased force and torque output across multiple degrees of freedom. Therefore, when grasping and moving materials, sufficiently large forces and torques need to be applied to the load-bearing parts of the parallel robot to complete these operations, which undoubtedly limits the breadth of robot applications. Summary of the Invention

[0003] Therefore, it is necessary to provide a multi-degree-of-freedom transmission device and robot, which aims to solve the problem that the existing technology cannot increase the output of forces and torques in multiple degrees of freedom.

[0004] A multi-degree-of-freedom transmission device includes a first platform, a second platform, a fixed platform disposed between the first platform and the second platform, a plurality of first branches, a plurality of second branches, and a plurality of transmission components, wherein:

[0005] The plurality of first branches are arranged in parallel between the first platform and the fixed platform, and the plurality of first branches, the first platform and the fixed platform constitute a first multi-degree-of-freedom parallel mechanism;

[0006] The plurality of second branches are arranged in parallel between the second platform and the fixed platform. The plurality of second branches, the second platform and the fixed platform constitute a second multi-degree-of-freedom parallel mechanism. The structure of the second branch is similar to that of the first branch, and the size of the second branch is proportionally enlarged or reduced compared to the size of the first branch.

[0007] The plurality of transmission components are coupled between the plurality of first branches and the plurality of second branches, for coupling the output end of the first multi-degree-of-freedom parallel mechanism to the input end of the second multi-degree-of-freedom parallel mechanism.

[0008] In one embodiment, the transmission assembly couples the output of the first multi-degree-of-freedom parallel mechanism to the input of the second multi-degree-of-freedom parallel mechanism at a 1:1 speed ratio.

[0009] In one embodiment, the end of the first branch away from the first platform is rotatably connected to the transmission assembly, and the end of the second branch away from the second platform is rotatably connected to the transmission assembly. There are three of each of the first and second branches. The three first branches, the first platform, and the fixed platform constitute a first 3-RRRS parallel mechanism, and the three second branches, the second platform, and the fixed platform constitute a second 3-RRRS parallel mechanism.

[0010] In one embodiment, the first branch includes a first ball joint, a first revolute joint, a second revolute joint, and a third revolute joint connected in sequence, wherein the first ball joint is connected to the first platform, the third revolute joint is connected to the fixed platform, and the first and second revolute joints are the output ends of the first multi-degree-of-freedom parallel mechanism; the second branch includes a second ball joint, a fourth revolute joint, a fifth revolute joint, and a sixth revolute joint connected in sequence, wherein the second ball joint is connected to the second platform, the fourth revolute joint is connected to the fixed platform, and the fifth and sixth revolute joints are the input ends of the second multi-degree-of-freedom parallel mechanism.

[0011] In one embodiment, the transmission assembly includes a first bevel gear connected to the first rotating joint, a second bevel gear connected to the second rotating joint, a third bevel gear connected to the fifth rotating joint, a fourth bevel gear connected to the sixth rotating joint, and a linkage assembly, wherein the linkage assembly is used to transmit the rotation of the first bevel gear and the second bevel gear to the third bevel gear and the fourth bevel gear, respectively.

[0012] In one embodiment, the linkage assembly includes a first drive shaft group, a second drive shaft group, and a third drive shaft group rotatably connected to a fixed platform. Each drive shaft group includes a first shaft and a second shaft rotatably disposed in the first shaft. The two ends of the first drive shaft group are respectively located on both sides of the fixed platform. The second drive shaft group and the third drive shaft group are located on the side of the fixed platform away from the first branch. The first drive shaft group and the third drive shaft group are vertically placed at both ends of the second drive shaft group. A fifth bevel gear is sleeved at both ends of each second shaft, and a sixth bevel gear is sleeved at both ends of each first shaft. The fifth and sixth bevel gears on the end of the first drive shaft group near the first branch mesh with the first bevel gear and the second bevel gear, respectively. The fifth and sixth bevel gears on the end of the third drive shaft group near the second branch mesh with the third bevel gear and the fourth bevel gear, respectively. The fifth and sixth bevel gears at both ends of the second drive shaft group mesh with the fifth and sixth bevel gears on the end of the first drive shaft group away from the first branch and the end of the third drive shaft away from the second branch, respectively.

[0013] In one embodiment, the fixed platform is provided with a plurality of support plates on one side where the second drive shaft group and the third drive shaft group are located. Each support plate has a set of support holes, and each second drive shaft group is rotatably inserted through a set of support holes.

[0014] In one embodiment, the fixed platform includes a fixed plate, three first connecting frames, and three second connecting frames. The fixed plate includes a central portion and three positioning portions evenly spaced around the central portion. The three first connecting frames are respectively fixed to the ends of the three positioning portions away from the central portion and located on the side of the fixed plate facing the first platform. The three second connecting frames are respectively fixed to the ends of the three positioning portions close to the central portion and located on the side of the fixed plate facing the second platform.

[0015] In one embodiment, the positioning part has a first through hole at one end away from the center part, and the first connecting frame includes two first fixing plates vertically fixed to the fixing plate and a first bearing plate vertically connected between the two first fixing plates. The first bearing plate has a first positioning hole corresponding to the first through hole, and a part of the transmission assembly is rotatably placed in the first through hole and the first positioning hole.

[0016] A robot includes the aforementioned multi-degree-of-freedom transmission device, wherein the first platform is a force-receiving platform and the second platform is an execution platform.

[0017] The aforementioned multi-degree-of-freedom transmission device and robot can, on the one hand, use a platform connected to the larger of the first and second branches as a force-bearing platform. Through two parallel multi-degree-of-freedom mechanisms placed on both sides of a fixed platform, the force and / or torque received by the force-bearing platform is transmitted to a platform (execution platform) connected to the smaller of the first and second branches. This increases the force and / or torque output to the platform connected to the smaller branch in the spatial multi-degree-of-freedom domain, while decreasing the displacement. On the other hand, it can also use a platform connected to the smaller of the first and second branches as a force-bearing platform. Through two parallel multi-degree-of-freedom mechanisms placed on both sides of a fixed platform, the force and / or torque received by the force-bearing platform is transmitted to the platform (execution platform) connected to the larger of the first and second branches. This decreases the force and / or torque output to the platform connected to the larger branch in the spatial multi-degree-of-freedom domain, while increasing the displacement. In this way, the amplification or reduction of the output force / torque in the spatial multi-degree-of-freedom domain, or the amplification or reduction of the output displacement in the spatial multi-degree-of-freedom domain, can be achieved as needed. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the disclosed drawings without creative effort.

[0019] Figure 1 This is a perspective view of a multi-degree-of-freedom transmission device according to an embodiment;

[0020] Figure 2 for Figure 1 Front view of the multi-degree-of-freedom transmission device shown;

[0021] Figure 3 This is a perspective view of a first branch, a transmission component, and a second branch according to an embodiment of this application;

[0022] Figure 4 for Figure 3 The front view of the first branch, transmission assembly and the second branch shown;

[0023] Figure 5 This is a perspective view of a first linkage assembly according to an embodiment of this application;

[0024] Figure 6 This is a perspective view of a first drive shaft assembly according to an embodiment of this application. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0027] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0028] In the description of the embodiments of this application, it should be understood that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly placed when the product of this application is used, or the orientation or positional relationship commonly understood by those skilled in the art. They are only for the convenience of describing this application and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0029] Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0030] The technical solutions in this application will now be described with reference to the accompanying drawings.

[0031] Please see Figures 1 to 2 According to one embodiment, a multi-degree-of-freedom transmission device 1 is provided for transmitting forces and torques in multiple directions, including a first platform 10, a second platform 20, a fixed platform 30, a plurality of first branches 40, a plurality of second branches 50, and a plurality of transmission components 60.

[0032] The first platform 10 and the second platform 20 are movable platforms, one of which is a force-bearing platform, i.e., a platform that receives external force loading, and the other is an execution platform, i.e., a platform that outputs force. The fixed platform 30 is located between the first platform 10 and the second platform 20 and is fixedly installed, such as being fixedly installed in a processing machine tool (not shown in the figure), or being fixedly connected to a bracket fixed to the ground.

[0033] Multiple first branches 40 are connected in parallel between the first platform 10 and the fixed platform 30. The multiple first branches 40, the first platform 10 and the fixed platform 30 constitute a first multi-degree-of-freedom parallel mechanism, enabling the first platform 10 to accept or output forces and torques in multiple directions.

[0034] Multiple second branches 50 are connected in parallel between the second platform 20 and the fixed platform 30. The multiple second branches 50, the second platform 20, and the fixed platform 30 constitute a second multi-degree-of-freedom parallel mechanism, enabling the second platform 20 to accept or output forces and torques in multiple directions. The fixed platform 30 can be a platform shared by the first and second multi-degree-of-freedom parallel mechanisms, or it can be formed by connecting the static platforms of each of the first and second multi-degree-of-freedom parallel mechanisms. The structure of the second branch 50 is similar to that of the first branch 40, and the size of the second branch 50 is proportionally enlarged or reduced compared to the size of the first branch 40. Specifically, the arrangement of multiple second branches 50 relative to the fixed platform 30 is basically the same as the arrangement of multiple first branches 40 relative to the fixed platform 30. The components included in the second branch 50 and the connection order between the components are basically the same as the components included in the first branch 40 and the connection order between the components. The only difference is that the size of each component included in the second branch 50 is proportionally enlarged or reduced compared to the size of the corresponding component in the first branch 40.

[0035] Multiple transmission components 60 are coupled between multiple first branches 40 and multiple second branches 50 for transmitting power to the output terminal 80 of the first multi-degree-of-freedom parallel mechanism (see [link]). Figure 3 ) Coupled to the input terminal 90 of the second multi-degree-of-freedom parallel mechanism (see Figure 3 In one embodiment, the transmission assembly 60 couples 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 1:1 speed ratio. This 1:1 speed ratio ensures that the force and / or torque, displacement output by the output end 80 of the first multi-degree-of-freedom parallel mechanism are the same as the force and / or torque, displacement acquired by the input end 90 of the second multi-degree-of-freedom parallel mechanism. This maintains the same rotation angle between the output end 80 and the input end 90 of the second multi-degree-of-freedom parallel mechanism. Furthermore, when the external force received by the first platform 10 or the second platform 20 (which serves as the force-bearing platform) is transmitted to the second platform 20 or the first platform 10 (which serves as the execution platform), the magnitude of the force and / or torque, displacement output on the spatial multi-degree-of-freedom of the execution platform can be adjusted by the size ratio of the first branch 40 and the second branch 50.

[0036] Because the multi-degree-of-freedom transmission device 1 has two parallel multi-degree-of-freedom mechanisms located on both sides of the fixed platform 30, regardless of the direction of the force and / or torque applied to the first platform 10 (i.e., when the first platform 10 is a force-bearing platform), the torque applied to the first platform 10 can be transmitted to the transmission assembly 60 through multiple first branches 40, then transmitted to the second branch 50 through the transmission assembly 60, and finally transmitted to the second platform 20, which serves as the execution platform, through the second branch 50. In this way, the multi-degree-of-freedom force and / or torque input on the first platform 10 can be transmitted to the execution end on the second platform 20, and the multi-degree-of-freedom displacement input on the first platform 10 can be transmitted to the execution end on the second platform 20.

[0037] Since the first platform 10 and the second platform 20 are moving platforms, and the fixed platform 30 is fixed, the first branch 40 and the second branch 50 are equivalent to the lever arms on both sides of the support point of a lever. Furthermore, since the dimensions of each component in the second branch 50 are enlarged or reduced according to the same preset ratio as the corresponding components in the first branch 40, when the force and / or torque received by the first platform 10 is transmitted through the multi-degree-of-freedom transmission device 1, it will be reduced or amplified on the second platform 20, thereby reducing or increasing the force and / or torque applied to the execution end of the second platform 20. Alternatively, the second platform 20 may receive torque, and the first platform 10 may output torque; that is, the second platform 20 acts as the force-receiving platform, and the first platform 10 acts as the execution platform. When the force and / or torque increases, the preset actions to be performed by the execution end on the execution platform can be achieved by applying a smaller force and / or torque to the force-bearing platform, such as gripping a workpiece, thus achieving easy gripping of the workpiece; when the force and / or torque decreases, it can prevent the execution object on the execution end of the execution platform from being damaged due to being subjected to a larger force and / or torque.

[0038] like Figure 1 In the illustrated embodiment, the dimensions of each component in the second branch 50 are scaled down by a ratio of 2:1 to the dimensions of the corresponding components in the first branch 40. When the first platform 10 serves as the force-bearing platform and the second platform 20 serves as the execution platform, the second platform 20 receives increased force and / or torque and decreased displacement. Thus, the output force / torque amplification function and displacement reduction function are realized in the spatial multi-degree-of-freedom area from the first platform 10 to the second platform 20. When the second platform 20 serves as the force-bearing platform and the first platform 10 serves as the execution platform, the first platform 10 receives decreased force and / or torque and increased displacement. Thus, the output force / torque reduction function and displacement amplification function are realized in the spatial multi-degree-of-freedom area from the second platform 20 to the first platform 10.

[0039] In one embodiment, such as Figure 1 and Figure 4As shown, the fixed platform 30 is generally Y-shaped, including 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 even intervals, and the angle between two adjacent positioning portions 312 is approximately 120°. Each positioning portion 312 has a first through hole 313 at one end away from the central portion 311. The three first connecting frames 32 are respectively fixed to the ends 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 fixing pieces 321 vertically fixed to the fixed plate 31 and a first bearing piece 322 vertically connected between the two first fixing pieces 321. The first support plate 322 has a first positioning hole 323 corresponding to the first through hole 313. A portion of the transmission assembly 60 is rotatably placed in the first through hole 313 and the first positioning hole 323. Three second connecting brackets 33 are respectively fixed to one end of the three positioning parts 312 near the center part 311 and located on the side of the fixing plate 31 facing the second platform 20. The structure of the second connecting bracket 33 is similar to that of the first connecting bracket 32, including two second fixing plates 331 vertically fixed to the fixing plate 31 and a second support plate 332 vertically connected between the two second fixing plates 331. The second support plate 332 has a second positioning hole 333, which is used to rotatably connect another part of the transmission assembly 60.

[0040] In some embodiments, there are three first branches 40 and three second branches 50. The three first branches 40 are evenly arranged between the first platform 10 and the three first connecting frames 32, and are connected to one end of the three transmission components 60 to transmit motion on the three first branches 40 or to transmit motion to the three first branches 40. In some embodiments, the three first branches 40, the first platform 10, and the fixed platform 30 constitute a first 3-RRRS parallel mechanism. The three second branches 50 are evenly arranged between the second platform 20 and the three second connecting frames 33, and are connected to the other end of the transmission components 60 to transmit motion on the second branches 50 or to transmit motion to the second branches 50. The three second branches 50, the second platform 20, and the fixed platform 30 constitute a second 3-RRRS parallel mechanism (RRRS refers to a branch consisting of three revolute joints (R) and one spherical joint (S). For a specific definition of the 3-RRRS parallel structure, please refer to the descriptions in existing technologies such as CN104950797A, CN101292935A, and WO2019126919A1, the entire contents of which are incorporated herein by reference. Since the moving platform of the 3-RRRS parallel structure has six degrees of freedom in space, the moving platforms of the two 3-RRRS parallel mechanisms are respectively used as the input and output platforms of the degree-of-freedom transmission device 1, enabling the transmission of six degrees of freedom motion between the first platform 10 and the second platform 20. It should be understood that the above-described first branch 40 and second branch 50 only provide one embodiment of the six-degree-of-freedom parallel structure. In other embodiments, the structure of the first branch 40 and second branch 50 can also be other six-degree-of-freedom parallel structures, or other multi-degree-of-freedom parallel mechanisms, such as three-degree-of-freedom parallel mechanisms, to realize three-degree-of-freedom motion between the first platform 10 and the second platform 20.

[0041] like Figure 1As shown, in some embodiments, the first branch 40 includes a first ball joint 41, a first rotary joint 44, a second rotary joint 45, and a third rotary joint 46 connected in sequence. The first ball joint 41 is connected to the first platform 10, and the third rotary joint 46 is connected to the fixed platform 30. The first rotary joint 44 and the second rotary joint 45 are the output ends 80 of the first multi-degree-of-freedom parallel mechanism, connected to one end of the transmission assembly 60. The first rotary joint 44 and the second rotary joint 45 are connected to the first ball joint 41, and their axes of rotation are parallel or coincident. The third rotary joint 46 is rotatably connected to the first rotary joint 44 and the second rotary joint 45, and its axis of rotation is perpendicular to the axes of rotation of the first rotary joint 44 and the second rotary joint 45. When the first platform 10 acts as a force-bearing platform and is subjected to force and / or torque, the force and / or torque on the first platform 10 are transmitted to the first revolute joint 44 and the second revolute joint 45 via the first ball joint 41, and then to the transmission assembly 60 connected to the first revolute joint 44 and the second revolute joint 45, and further transmitted to the second platform 20 via the transmission assembly 60 and the second branch chain 50. When the first revolute joint 44 and the second revolute joint 45 transmit motion to the transmission assembly 60, the rotation of the first revolute joint 44 and the second revolute joint 45 relative to the stationary platform 30 can be achieved via the third revolute joint 46, avoiding twisting and deformation of the first revolute joint 44 and the second revolute joint 45 during rotation.

[0042] Specifically, please refer to Figure 5 The first ball joint 41 includes a universal joint 411, a first rotating rod 412 connected to one end of the universal joint 411, a second rotating rod 413 connected to the other end of the universal joint 411, and a first connecting rod 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 connecting rod assembly 414. In this embodiment, the first platform 10 is generally circular, and three fixing blocks 417 are fixed to the edge of the first platform 10. Each fixing block 417 is provided with a first bearing 418. The end of the first rotating rod 412 away from the second rotating rod 413 is rotatably placed in the first bearing 418 to realize the rotatable 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 linkages 415, a second bearing 425 fixed between the two first linkages 421, and a second rotating rod 413 rotatably connected to the second bearing 416 to achieve a rotatable 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.

[0043] Please see Figure 3The first revolute joint 44 includes a second link 441, a third link 442, and a first rotating shaft 443. One end of the second link 441 is vertically and rotatably connected to the two first links 415 of the first link assembly 414, and the other end of the second link 441 is vertically fixed to one end of the third link 442. The first rotating shaft 443 is fixedly connected to the end of the third link 442 away from the second link 441 and is rotatably connected to the third revolute joint 46. The first rotating shaft 443 and the second link 441 are located on the same side of the third link 442.

[0044] The second revolute joint 45 includes a fourth link 451, a fifth link 452, a sixth link 453, and a second rotating shaft 454. One end of the fourth link 451 is vertically and rotatably connected to the two first links 415 of the first link assembly 414, and is positioned further away from the second rotating rod 413 than the second link 441. The other end of the fourth link 451 is vertically fixed to one end of the fifth link 452, and the other end of the fifth link 452 is rotatably connected to one end of the sixth link 453. The sixth link 453 and the fourth link 451 are located on the same side of the fifth link 452. The second rotating shaft 454 is fixedly connected to the other end of the sixth link 453 and is rotatably connected to the third revolute joint 46.

[0045] The third rotating joint 46 includes a first support 461 and a third rotating shaft 462. The first rotating shaft 443 and the second rotating shaft 454 are rotatably connected to the first support 461. The third rotating shaft 462 is connected to the first support 461 and rotatably connected to the fixed platform 30, thereby realizing the rotatable connection between the third rotating joint 46 and the fixed platform 30.

[0046] Specifically, please refer to [the relevant document] again. Figure 1 The first support 461 includes two parallel first vertical plates 463 and a first horizontal plate 464 vertically connected between the two first vertical plates 463. A third rotating shaft 462 is connected to the first horizontal plate 464. A third connecting rod 442 and a sixth connecting rod 453 are disposed on the outer side of the two first vertical plates 463. Each first vertical plate 463 has a first transverse through hole 465 parallel to the fixed platform 30. The first rotating shaft 443 and the second rotating shaft 454 are rotatably passed through the two first transverse through holes 465 to realize the rotatable connection between the first rotating joint 44 and the second rotating joint 45 and the third rotating joint 46. The first horizontal plate 464 has a first vertical through hole 466 aligned with the first positioning hole 323. A part of the transmission assembly 60 is rotatably placed in the first through hole 313, the first positioning hole 323, and the first vertical through 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 through hole 466, and the conveying assembly 60 is rotatably placed in the first through hole 313, the first positioning hole 323, the first vertical through hole 466 and the limiting hole.

[0047] The second branch 50 includes a second ball joint 51, a fourth rotary joint 56, a fifth rotary joint 54, and a sixth rotary joint 55 connected in sequence. The second ball joint 51 is connected to the second platform 20, the fourth rotary joint 56 is connected to the fixed platform 30, and the fifth and sixth rotary joints 54 and 55 are the input ends 90 of the second multi-degree-of-freedom parallel mechanism, connected to the other end of the transmission assembly 60. The structures and connections of the second ball joint 51, fourth rotary joint 56, fifth rotary joint 54, and sixth rotary joint 55 are the same as those of the first ball joint 41, first rotary joint 44, second rotary joint 45, and third rotary joint 46, and will not be repeated here. The dimensions of the second ball joint 51, fourth rotary joint 56, fifth rotary joint 54, and sixth rotary joint 55 are proportionally enlarged or reduced from the dimensions of the first ball joint 41, first rotary joint 44, second rotary joint 45, and third rotary joint 46. The fourth revolute joint 56 is rotatably connected to the second bearing plate 332 of the fixed platform 30. The fifth revolute joint 54 and the sixth revolute joint 55 are rotatably connected to the fourth revolute joint. The axes of rotation of the fifth revolute joint 54 and the sixth revolute joint 55 are parallel or coincident, and the axis of rotation of the fourth revolute joint 56 is perpendicular to the axes of rotation of the fifth revolute joint 54 and the sixth revolute joint 55. When the torque received by the first revolute joint 44 and the second revolute joint 45 is transmitted to the transmission assembly 60, it can be transmitted to the fifth revolute joint 54 and the sixth revolute joint 55 through the transmission assembly 60, and then transmitted to the second platform 20 through the second ball joint 51. When the torque received by the first revolute joint 44 and the second revolute joint 45 is transmitted to the fifth revolute joint 54 and the sixth revolute joint 55 through the transmission assembly 60, the rotation of the fifth revolute joint 54 and the sixth revolute joint 55 relative to the fixed platform 30 can be achieved through the fourth revolute joint 56, thereby avoiding the torsional deformation of the fifth revolute joint 54 and the sixth revolute joint 55.

[0048] The first and second multi-degree-of-freedom parallel mechanisms are not limited to the aforementioned 3-RRRS parallel mechanism; they can also be other parallel mechanisms, such as the 3-URS parallel mechanism (URS refers to a branch consisting of a universal joint (U), a revolute joint (R), and a spherical joint (S)). Any parallel mechanism capable of realizing multiple degrees of freedom is acceptable. For example, if both the first and second multi-degree-of-freedom parallel mechanisms are three-degree-of-freedom parallel mechanisms, then the multi-degree-of-freedom transmission device 1 can transmit three-degree-of-freedom spatial motion.

[0049] Please see Figure 2 , Figure 3 and Figure 6The transmission assembly 60 includes a first bevel gear 61 connected to a first revolute joint 44, a second bevel gear 62 connected to a second revolute joint 45, a third bevel gear 63 connected to a fifth revolute joint 54, a fourth bevel gear 64 connected to a sixth revolute joint 55, and a linkage assembly 65. The pitch circle diameter of the first bevel gear 61 is smaller than that of the second bevel gear 62, and the pitch circle diameter of the third bevel gear 63 is smaller than that of the fourth bevel gear 64. The linkage assembly 65 is used to transmit the rotation of the first bevel gear 61 and the second bevel gear 62 to the third bevel gear 63 and the fourth bevel gear 64, respectively.

[0050] The linkage assembly 65 includes a first drive shaft assembly 66, a second drive shaft assembly 67, and a third drive shaft assembly 68 rotatably connected to the fixed platform 30. The first drive shaft assembly 66 rotatably passes through a first through hole 313, a first positioning hole 323, and a first vertical through hole 466, with its two ends located on opposite sides of the fixed platform 30. The second drive shaft assembly 67 and the third drive shaft assembly 68 are positioned on one side of the fixed platform 30, with the first drive shaft assembly 66 and the third drive shaft assembly 68 vertically connected to the two ends of the second drive shaft assembly 67. A plurality of support plates 34 are fixed to the side of the fixed platform 30 where the second drive shaft assembly 67 and the third drive shaft assembly 68 are located. Each support plate 34 has a set of coaxial support holes 35, the central axis of which is parallel to the fixed platform 30. Each second drive shaft assembly 67 rotatably passes through a set of support holes 35. The third drive shaft assembly 68 is rotatably disposed in the holes corresponding to the first vertical through hole 46 on the second positioning hole 333 and the fourth rotating pair 56.

[0051] Each of the first drive shaft group 66, the second drive shaft group 67, and the third drive shaft group 68 includes a first shaft 69 and a second shaft 70 rotatably disposed within the first shaft 69. A fifth bevel gear 71 is fitted at each end of each second shaft 70, and a sixth bevel gear 72 is fitted at each end of each first shaft 69. The fifth bevel gear 71 and the sixth bevel gear 72 on the first drive shaft group 66, near the end of the first branch 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 on the third drive shaft group 68, near the end of the second branch 50, 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 at both ends of the second drive shaft group 67 mesh with the fifth bevel gear 71 and the sixth bevel gear 72 on the first drive shaft group 66 and the third drive shaft group 68, respectively, at the ends away from the first branch 40. Thus, the 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 through the fifth bevel gear 71 sleeved at both ends of the second shaft 70 and the sixth bevel gear 72 sleeved at both ends of the first shaft 69.

[0052] 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 on the output end 80 of the first multi-degree-of-freedom parallel mechanism, namely the first rotary joint 44 and the second rotary joint 45, to the input end 90 of the second multi-degree-of-freedom parallel mechanism, namely the fifth rotary joint 54 and the sixth rotary joint 55, at a speed ratio of 1:1.

[0053] The transmission component 66 is not limited to the bevel gear transmission structure described above, but can also be other transmission mechanisms, such as worm gear transmission structures, as long as it can transmit the motion between two multi-degree-of-freedom parallel mechanisms.

[0054] This application also provides a robot, which includes the aforementioned multi-degree-of-freedom transmission device 1, a first platform 10 as a force-receiving platform for receiving applied forces and / or torques, and a second platform 20 as an execution platform for processing or transferring products through the execution end on the execution platform.

[0055] The aforementioned multi-degree-of-freedom transmission device 1 and robot, on the one hand, can transmit the force and / or torque received by the platform connected to the larger of the first branch 40 and the second branch 50 as the force-bearing platform, through two multi-degree-of-freedom parallel mechanisms placed on both sides of the fixed platform 30, to the platform (execution platform) connected to the smaller of the first branch 40 and the second branch 50, thereby increasing the force and / or torque output to the platform connected to the smaller branch in the spatial multi-degree-of-freedom domain and decreasing the displacement; on the other hand, can transmit the force and / or torque received by the platform connected to the smaller of the first branch and the second branch as the force-bearing platform, through two six-degree-of-freedom parallel mechanisms placed on both sides of the fixed platform, to the platform (execution platform) connected to the larger of the first branch 40 and the second branch 50, thereby decreasing the force and / or torque output to the platform connected to the larger branch in the spatial multi-degree-of-freedom domain and increasing the displacement. In this way, the output force / torque can be amplified or reduced in multiple degrees of freedom in space, or the output displacement can be amplified or reduced in multiple degrees of freedom in space, as needed.

[0056] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0057] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A multi-degree-of-freedom transmission device, characterized in that, It includes a first platform, a second platform, a fixed platform disposed between the first platform and the second platform, multiple first branches, multiple second branches, and multiple transmission components, wherein: The plurality of first branches are arranged in parallel between the first platform and the fixed platform, and the plurality of first branches, the first platform and the fixed platform constitute a first multi-degree-of-freedom parallel mechanism; The plurality of second branches are arranged in parallel between the second platform and the fixed platform. The plurality of second branches, the second platform and the fixed platform constitute a second multi-degree-of-freedom parallel mechanism. The structure of the second branch is similar to that of the first branch, and the size of the second branch is proportionally enlarged or reduced compared to the size of the first branch, so as to realize the function of amplifying or reducing the output force / torque in multiple degrees of freedom. The plurality of transmission components are coupled between the plurality of first branches and the plurality of second branches, for coupling the output end of the first multi-degree-of-freedom parallel mechanism to the input end of the second multi-degree-of-freedom parallel mechanism.

2. The multi-degree-of-freedom transmission device according to claim 1, characterized in that, The transmission assembly couples the output of the first multi-degree-of-freedom parallel mechanism to the input of the second multi-degree-of-freedom parallel mechanism at a 1:1 speed ratio.

3. The multi-degree-of-freedom transmission device according to claim 1, characterized in that, The number of the first branch and the second branch are both three. The three first branches, the first platform and the fixed platform constitute a first 3-RRRS parallel mechanism, and the three second branches, the second platform and the fixed platform constitute a second 3-RRRS parallel mechanism.

4. The multi-degree-of-freedom transmission device according to claim 3, characterized in that, The first branch includes a first ball joint, a first revolute joint, a second revolute joint, and a third revolute joint connected in sequence, wherein the first ball joint is connected to the first platform, the third revolute joint is connected to the fixed platform, and the first and second revolute joints are the output ends of the first multi-degree-of-freedom parallel mechanism; the second branch includes a second ball joint, a fourth revolute joint, a fifth revolute joint, and a sixth revolute joint connected in sequence, wherein the second ball joint is connected to the second platform, the fourth revolute joint is connected to the fixed platform, and the fifth and sixth revolute joints are the input ends of the second multi-degree-of-freedom parallel mechanism.

5. The multi-degree-of-freedom transmission device according to claim 4, characterized in that, The transmission assembly includes a first bevel gear connected to the first rotating joint, a second bevel gear connected to the second rotating joint, a third bevel gear connected to the fifth rotating joint, a fourth bevel gear connected to the sixth rotating joint, and a linkage assembly. The linkage assembly is used to transmit the rotation of the first bevel gear and the second bevel gear to the third bevel gear and the fourth bevel gear, respectively.

6. The multi-degree-of-freedom transmission device according to claim 5, characterized in that, The linkage assembly includes a first transmission shaft group, a second transmission shaft group, and a third transmission shaft group that are rotatably connected to the fixed platform. Each transmission shaft group includes a first shaft and a second shaft rotatably disposed in the first shaft. The two ends of the first drive shaft assembly are located on both sides of the fixed platform, the second drive shaft assembly and the third drive shaft assembly are located on one side of the fixed platform, and the first drive shaft assembly and the third drive shaft assembly are vertically connected to the two ends of the second drive shaft assembly. A fifth bevel gear is fitted at both ends of each second shaft, and a sixth bevel gear is fitted at both ends of each first shaft. The fifth and sixth bevel gears on the first drive shaft assembly near the first branch mesh with the first bevel gear and the second bevel gear, respectively. The fifth and sixth bevel gears on the third drive shaft assembly near the second branch mesh with the third bevel gear and the fourth bevel gear, respectively. The fifth and sixth bevel gears at both ends of the second drive shaft assembly mesh with the fifth and sixth bevel gears on the first drive shaft assembly away from the first branch and the third drive shaft assembly away from the second branch, respectively.

7. The multi-degree-of-freedom transmission device according to claim 6, characterized in that, The fixed platform is provided with a second drive shaft assembly and a third drive shaft assembly. A plurality of support plates are fixed on one side of the platform. Each support plate has a set of support holes, and each second drive shaft assembly is rotatably inserted through a set of support holes.

8. The multi-degree-of-freedom transmission device according to claim 3, characterized in that, The fixed platform includes a fixed plate, three first connecting frames, and three second connecting frames. The fixed plate includes a central portion and three positioning portions evenly spaced around the central portion. The three first connecting frames are respectively fixed to the ends of the three positioning portions away from the central portion and located on the side of the fixed plate facing the first platform. The three second connecting frames are respectively fixed to the ends of the three positioning portions close to the central portion and located on the side of the fixed plate facing the second platform.

9. The multi-degree-of-freedom transmission device according to claim 8, characterized in that, The positioning part is provided with a first through hole at one end away from the center part. The first connecting frame includes two first fixing plates that are vertically fixed to the fixing plate and a first bearing plate that is vertically connected between the two first fixing plates. The first bearing plate has a first positioning hole corresponding to the first through hole. A part of the transmission component is rotatably placed in the first through hole and the first positioning hole.

10. A robot, characterized in that, The device includes a multi-degree-of-freedom transmission device as described in any one of claims 1 to 9, wherein the first platform is a force-bearing platform and the second platform is an execution platform.

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