Three-degree-of-freedom joint, mechanical arm and robot

Abstract

The utility model relates to the technical field of robots, and provides a three-degree-of-freedom joint, a mechanical arm and a robot, and the joint comprises a universal rotating shaft, a plurality of supporting legs and two supporting discs which are oppositely arranged at intervals; the two ends of the universal rotating shaft are arranged between the middles of the two supporting discs through a first connecting part, and the first connecting part is provided with two rotating axes perpendicular to each other. The multiple supporting legs are obliquely arranged between the two supporting discs, the multiple supporting legs are evenly distributed on the outer side of the universal rotating shaft in the circumferential direction, the ends of the supporting legs are connected to the supporting discs through second connecting parts, and the second connecting parts are provided with two rotating axes perpendicular to each other. According to the three-degree-of-freedom joint, the supporting legs are obliquely arranged between the two supporting discs, so that the two supporting discs can relatively turn over, pitching and yawing two-degree-of-freedom movement in the space is achieved, the universal rotating shaft achieves rolling degree-of-freedom movement, and then the three-degree-of-freedom joint is expanded to three degrees of freedom so as to improve the flexibility; and through the arrangement of the three supporting legs, the load capacity is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of robots, in particular to a three-degree-of-freedom joint, a robotic arm and a robot. Background Art

[0002] With the progress of technology, the research and application fields of robots are constantly expanding, making robots an important part of daily life and work. The robotic arm is an important moving part of the robot, the basis for the robot to complete operations such as grasping and human-machine interaction, and the key to evaluating the motion flexibility of the robot is the degree-of-freedom motion design of the motion joint.

[0003] In the prior art, the motion joints of the robotic arm are mostly single-degree-of-freedom, with poor flexibility and weak load capacity at the joints. Summary of the Utility Model

[0004] The utility model provides a three-degree-of-freedom joint, a robotic arm and a robot to solve the defects of poor flexibility and weak load capacity of the robotic arm in the prior art.

[0005] The utility model provides a three-degree-of-freedom joint, comprising:

[0006] Two support disks, arranged opposite to each other at intervals;

[0007] A universal rotating shaft, both ends of the universal rotating shaft are arranged between the middles of the two support disks through a first connecting component, and the first connecting component has two mutually perpendicular rotation axes;

[0008] A plurality of legs, inclined and arranged between the two support disks, the plurality of legs are circumferentially and evenly distributed outside the universal rotating shaft, and the ends of the legs are connected to the support disks through a second connecting component, and the second connecting component has two mutually perpendicular rotation axes.

[0009] According to the three-degree-of-freedom joint provided by the utility model, the universal rotating shaft is in a straight rod shape, the first connecting component comprises a rotating shaft, the rotating shaft has a first rotating shaft and a second rotating shaft arranged perpendicularly, the first rotating shaft is rotationally connected to the end of the universal rotating shaft, and the second rotating shaft is rotationally arranged in the middle of the support disk.

[0010] According to the three-degree-of-freedom joint provided by the utility model, a rotating support is arranged in the middle of the support disk, the second rotating shaft is rotationally arranged on the rotating support, and the rotation axis of the rotating support is perpendicular to the rotation axis of the first rotating shaft and the rotation axis of the second rotating shaft.

[0011] According to a three - degree - of - freedom joint provided by the present utility model, the rotary support has a first transmission gear, the support disk has a second transmission gear meshing with the first transmission gear, and a steering pulley is arranged on the support disk.

[0012] According to a three - degree - of - freedom joint provided by the present utility model, the second connecting component includes a transfer shaft, the transfer shaft has a first rotating shaft and a second rotating shaft which are vertically and staggeredly arranged, the first rotating shaft is rotatably connected to the end of the leg, and the second rotating shaft is rotatably connected to the support disk;

[0013] The rotation axes of the second rotating shafts on the same side of multiple legs intersect at the central axis of the universal rotating shaft.

[0014] According to a three - degree - of - freedom joint provided by the present utility model, the support disk has a shaft seat rotatably connected to the second rotating shaft, and the end of the leg has an ear rotatably connected to the first rotating shaft;

[0015] One of the space between the shaft seat and the second rotating shaft and the space between the ear and the first rotating shaft is a clearance fit, and the other is an interference fit.

[0016] According to a three - degree - of - freedom joint provided by the present utility model, there are at least three legs, and the diameter of the first circle formed by the first ends of multiple legs is equal to the diameter of the second circle formed by the second ends of multiple legs.

[0017] According to a three - degree - of - freedom joint provided by the present utility model, the projection of the first end of the leg on the support disk and the projection of the second end of the leg on the support disk have an offset distance, and the offset distance is equal to the diameter of the first circle.

[0018] The present utility model also provides a robotic arm, including the three - degree - of - freedom joint described in any one of the above.

[0019] The present utility model also provides a robot, including the three - degree - of - freedom joint described in any one of the above or the above - mentioned robotic arm.

[0020] The three-degree-of-freedom joint provided by the present utility model has multiple legs inclined between two support disks. The ends of the legs are rotationally connected to the support disks through second connecting members. The second connecting members have two mutually perpendicular rotational axes. In this way, the two support disks can relatively flip, realizing the two-degree-of-freedom motion of pitching and yawing in space. The universal rotating shaft realizes the rolling-degree-of-freedom motion, and further expands the three-degree-of-freedom joint to three degrees of freedom, so as to deflect in various angles in space to improve flexibility; and through the arrangement of the three legs, the stability of the three-degree-of-freedom motion is improved, thereby improving the stiffness and safety of the three-degree-of-freedom joint, and further improving the load capacity. Brief Description of the Drawings

[0021] In order to more clearly illustrate the technical solutions in the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0022] Figure 1 is one of the structural schematic diagrams of the three-degree-of-freedom joint provided by the present utility model.

[0023] Figure 2 is the second structural schematic diagram of the three-degree-of-freedom joint provided by the present utility model.

[0024] Figure 3 is the third structural schematic diagram of the three-degree-of-freedom joint provided by the present utility model.

[0025] Figure 4 is the fourth structural schematic diagram of the three-degree-of-freedom joint provided by the present utility model.

[0026] Figure 5 is the structural schematic diagram of the first support disk provided by the present utility model.

[0027] Figure 6 is the structural schematic diagram of the second support disk provided by the present utility model.

[0028] Figure 7 is one of the structural schematic diagrams of the leg provided by the present utility model.

[0029] Figure 8 is the second structural schematic diagram of the leg provided by the present utility model.

[0030] Figure 9 is the structural schematic diagram of the adapter shaft provided by the present utility model.

[0031] Figure 10It is a structural schematic diagram of the cooperation between the universal rotating shaft and the first supporting disk provided by the utility model.

[0032] Figure 11 It is a structural schematic diagram of the universal shaft provided by the utility model.

[0033] Figure numerals: 10, first support plate; 11, first shaft seat; 20, second support plate; 21, second shaft seat; 30, universal joint; 31, third hanging ear; 32, fourth hanging ear; 40, support leg; 41, first hanging ear; 42, second hanging ear; 50, rotating shaft; 51, first rotating shaft; 52, second rotating shaft; 60, adapter shaft; 61, first rotating shaft; 62, second rotating shaft; 63, first shaft hole; 64, second shaft hole; 71, rotating support; 72, first transmission gear; 73, second transmission gear; 80, steering pulley. DETAILED DESCRIPTION

[0034] The following is a further detailed description of the implementation of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0035] In the description of the embodiments of the present utility model, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present utility model. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0036] In the description of the embodiments of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to specific circumstances.

[0037] In the embodiments of the present utility model, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the horizontal height of the first feature is less than that of the second feature.

[0038] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of the present utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0039] The following combines Figures 1 - 11 to describe the three-degree-of-freedom joint of the embodiments of the present utility model.

[0040] An embodiment of the first aspect of the present utility model provides a three-degree-of-freedom joint, as Figure 1 and Figure 4 shown. The three-degree-of-freedom joint includes two support disks, and a universal rotating shaft 30 and a plurality of legs 40 disposed between the two support disks.

[0041] The two support disks are disposed opposite to each other at intervals. The universal rotating shaft 30 is disposed between the middles of the two support disks. The two ends of the universal rotating shaft 30 are rotatably disposed on the support disks through a first connecting member. The first connecting member has two mutually perpendicular rotation axes; the plurality of legs 40 are obliquely disposed between the two support disks. The plurality of legs 40 are circumferentially distributed on the outer side of the universal rotating shaft 30. The ends of the legs 40 are rotatably connected to the support disks through a second connecting member. The second connecting member has two mutually perpendicular rotation axes.

[0042] It can be understood that one end of the universal rotating shaft 30 is rotatably connected to the middle of one of the support disks through the first connecting member, and the other end of the universal rotating shaft 30 is rotatably connected to the middle of the other support disk through the first connecting member; one end of the support leg 40 is rotatably connected to one of the support disks through the second connecting member, and the other end of the support leg 40 is rotatably connected to the other support disk through the second connecting member. The plurality of support legs 40 are arranged in a triangular shape on adjacent support disks. The plurality of support legs 40 are inclined between the two support disks and are evenly distributed outside the universal rotating shaft 30; the second connecting member has two mutually perpendicular rotation axes. One end of the second connecting member is rotatably connected to the support disk to form a structure that can be flipped, so as to form a rotatable angle range between the second connecting member and the support disk. The other end of the second connecting member is rotatably connected to the support leg 40 to form a structure that can be flipped, so as to form a rotatable angle range between the second connecting member and the support leg 40. The rotation axis of the second connecting member and the support disk is perpendicular to the rotation axis of the second connecting member and the support leg 40.

[0043] It should be noted that as Figure 3 and Figure 4 shown, the fact that the plurality of support legs 40 are inclined between the two support disks means that the plurality of support legs 40 are circumferentially inclined in sequence around the central axis of the universal rotating shaft 30, so that the plurality of support legs 40 are arranged between the two support disks in a shape like a "twisted rope".

[0044] It should be pointed out that the support legs 40 between the two support disks form an anti-parallelogram with one redundant side removed, that is, the second connecting member of one side support disk, the support leg 40, and the second connecting member of the other side support disk are rotatably connected in sequence; the rotation axis of the second connecting member and the support disk is skew perpendicular to the rotation axis of the second connecting member and the support leg 40 to form an anti-parallelogram. In this way, the two support disks can be flipped relative to each other by 90°, realizing the double-degree-of-freedom motion of pitching and yawing in space, and further expanding the entire three-degree-of-freedom joint to two degrees of freedom, so as to deflect in various angles in space.

[0045] It should be noted that a universal rotating shaft 30 is also provided between the middles of the two support disks, and the universal rotating shaft 30 is connected to the middle of the support disk through the first connecting member. The first connecting member also has two mutually perpendicular rotation axes. Thus, when the two support disks are flipped relative to each other, the universal rotating shaft 30 can improve the stability of the movement of the support disk, and further improve the stiffness and safety of the three-degree-of-freedom joint.

[0046] The three-degree-of-freedom joint provided by the embodiment of the present utility model has multiple legs 40 inclined between two support disks. The ends of the legs 40 are rotatably connected to the support disks through second connecting members, and the second connecting members have two mutually perpendicular rotation axes. In this way, the two support disks can relatively flip, realizing the two-degree-of-freedom motion of pitching and yawing in space, and the universal rotating shaft realizes the rolling-degree-of-freedom motion. Furthermore, the three-degree-of-freedom joint is extended to three degrees of freedom, so as to deflect in various angles in space to improve flexibility; and through the arrangement of three legs, the stability of the three-degree-of-freedom motion is improved, thereby improving the stiffness and safety of the three-degree-of-freedom joint, and further improving the load capacity.

[0047] According to the embodiment of the present utility model, as Figures 1 - 4 shown, multiple legs 40 are all arranged in a triangular shape on the support disk. For example, the number of legs 40 is three. When the three legs 40 are connected to the support disk, three points are formed on the support disk, so that the three legs 40 are arranged in a triangular shape on the support disk.

[0048] It can be understood that the three legs 40 are inclined between two support disks, and the rotational connection positions of the second connecting members at the ends of the three legs 40 on the support disk are distributed in a triangular shape on the support disk.

[0049] In an embodiment of the present utility model, the number of legs 40 is at least three, and the diameter of the first circle formed by the first ends of the multiple legs 40 is equal to the diameter of the second circle formed by the second ends of the multiple legs 40.

[0050] It can be understood that the two support disks are respectively denoted as the first support disk 10 and the second support disk 20. The first ends of the legs 40 are connected to the first support disk 10 through second connecting members, and the second ends of the legs 40 are connected to the second support disk 20 through second connecting members. The multiple legs 40 are circumferentially and evenly distributed on the outside of the universal rotating shaft 30. Then, the first ends of the multiple legs 40 form a first circle, and the second ends of the multiple legs 40 form a second circle, and the diameter of the first circle is equal to the diameter of the second circle.

[0051] Specifically, the first support disk 10 has multiple first rotational connection positions corresponding to the multiple legs, and the second support disk 20 has multiple second rotational connection positions corresponding to the multiple legs. The diameters of the circles on which the multiple first rotational connection positions are evenly distributed are equal to the diameters of the circles on which the multiple second rotational connection positions are evenly distributed.

[0052] Furthermore, the projection of the first end of the leg 40 on the support disk and the projection of the second end of the leg 40 on the support disk have an offset distance, and the offset distance is equal to the diameter of the first circle.

[0053] For example, as Figure 4 、 Figure 7 and Figure 8As shown, the number of outriggers 40 is three. There are three first rotation connection positions evenly distributed circumferentially on the first support disk 10. The three first rotation connection positions are sequentially denoted as the first rotation connection position A, the first rotation connection position B, and the first rotation connection position C in the circumferential direction. There are three second rotation connection positions evenly distributed circumferentially on the second support disk 20. The three second rotation connection positions are sequentially denoted as the second rotation connection position A, the second rotation connection position B, and the second rotation connection position C in the circumferential direction. The first rotation connection position A and the second rotation connection position A coincide along the relative setting direction of the two support disks. The first rotation connection position B and the second rotation connection position B coincide along the relative setting direction of the two support disks. The first rotation connection position C and the second rotation connection position C coincide along the relative setting direction of the two support disks.

[0054] One end of one of the outriggers 40 is connected to the first rotation connection position A, and the other end of the outrigger 40 is connected to the second rotation connection position B. The first rotation connection position A and the second rotation connection position B form an offset distance L, that is, the projection of the first end of the outrigger 40 on the support disk and the projection of the second end of the outrigger 40 on the support disk have an offset distance L, and the offset distance is equal to the diameter of the first circle. It should be noted here that if the diameter of the first circle is equal to the diameter of the second circle, then the offset distance, the diameter of the first circle, and the diameter of the second circle are equal.

[0055] In an embodiment of the present invention, as Figure 3 and Figure 10 shown, the universal rotating shaft 30 is in the shape of a straight rod. The first connecting component includes a rotating shaft 50 arranged between the universal rotating shaft 30 and the support disk. The rotating shaft 50 has a first rotating shaft 51 and a second rotating shaft 52 arranged vertically. The first rotating shaft 51 is rotationally connected to the end of the universal rotating shaft 30, and the second rotating shaft 52 is rotatably arranged in the middle of the support disk.

[0056] As Figure 11 shown, the first end of the universal rotating shaft 30 has a third hanging ear 31, and the second end of the universal rotating shaft 30 has a fourth hanging ear 32. The axes of the third hanging ear 31 and the fourth hanging ear 32 are arranged in parallel. The third hanging ear 31 and the fourth hanging ear 32 are rotationally connected to the first rotating shaft 51 of the corresponding rotating shaft 50.

[0057] Furthermore, a rotating support 71 is arranged in the middle of the support disk. The second rotating shaft 52 is rotatably arranged on the rotating support 71. The rotation axis of the rotating support 71 is perpendicular to the rotation axis of the first rotating shaft 51 and the rotation axis of the second rotating shaft 52.

[0058] It can be understood that mounting through holes are provided in the middle parts of both the first support plate 10 and the second support plate 20. The rotary support 71 is installed in the mounting through hole, and the rotary support 71 can rotate within the through hole. Both ends of the universal rotating shaft 30 are rotationally connected to the rotary supports 71 in the middle parts of the two support plates through corresponding first connecting components. In this way, the rotational freedom degree of the joint is achieved.

[0059] Optionally, as Figure 2 , Figure 10 and Figure 11 shown, the rotary support 71 has a first transmission gear 72, and the support plate has a second transmission gear 73 meshing with the first transmission gear 72.

[0060] It can be understood that the rotary support 71 is rotatably installed in the middle part of the support plate. One end of the rotary support 71 is rotationally connected to the second rotating shaft 52 of the rotary connection shaft 50. The other end of the rotary support 71 is provided with a first transmission gear 72, and the support plate has a second transmission gear 73 meshing with the first transmission gear 72. Thus, under the action of the first transmission gear 72 and the second transmission gear 73, the rotary support 71 and the support plate can rotate synchronously. Further, the second transmission gear 73 is coaxially arranged outside the first transmission gear 72, and an intermediate transmission gear is also provided between the first transmission gear 72 and the second transmission gear 73.

[0061] In an embodiment of the present utility model, as Figure 3 , Figure 4 and Figure 9 shown, the second connecting component includes a transfer shaft 60 arranged between the end of the leg 40 and the support plate. The transfer shaft 60 has a first rotating shaft 61 and a second rotating shaft 62 arranged vertically and staggeredly. The first rotating shaft 61 is rotationally connected to the end of the leg 40, and the end of the leg 40 has an ear for rotational connection with the first rotating shaft 61; the second rotating shaft 62 is rotationally connected to the support plate, and the support plate has a shaft seat for rotational connection with the second rotating shaft 62; the rotation axes of the second rotating shafts 62 on the same side of multiple legs 40 intersect at the central axis of the universal rotating shaft 30.

[0062] Exemplarily, there are three legs 40. As Figure 5 shown, the first support plate 10 has three first shaft seats 11 corresponding to the first ends of the three legs 40; as Figure 6 shown, the second support plate 20 has three second shaft seats 21 corresponding to the second ends of the three legs 40. The three first shaft seats 11 are circumferentially evenly distributed, the three second shaft seats 21 are circumferentially evenly distributed, and the positions of the three second shaft seats 21 and the three first shaft seats 11 correspond one by one along the relative setting direction of the two support plates.

[0063] Specifically, the specific connection between the end of the outrigger 40, the adapter shaft 60, and the support disk can be as follows: There is a clearance fit between the axle seat and the second rotating shaft 62 to ensure unobstructed rotation, and a tight fit between the lug and the first rotating shaft 61 to ensure that the adapter shaft 60 does not fall off. Of course, in other embodiments, it can also be that there is a tight fit between the axle seat and the second rotating shaft 62 to ensure that the adapter shaft 60 does not fall off, and a clearance fit between the lug and the first rotating shaft 61 to ensure unobstructed rotation.

[0064] In this embodiment, the clearance fit is a small clearance fit, and this clearance fit can be H7g6~H7g10, preferably H7g6. The tight fit can be H7k6~H7k6, preferably H7k6.

[0065] Exemplarily, as Figure 9 shown, two shaft holes are arranged on the adapter shaft 60, namely the first shaft hole 63 and the second shaft hole 64. The axes of the first shaft hole 63 and the second shaft hole 64 are vertically staggered. A rotating shaft is provided in the first shaft hole 63 to form the first rotating shaft 61, and a rotating shaft is provided in the second shaft hole 64 to form the second rotating shaft 62.

[0066] In an embodiment of the present utility model, the outrigger 40 is an arc-shaped structure, and the arc-shaped surface of the outrigger 40 preferably faces outward. After adopting this setting method, when the three-degree-of-freedom joint rotates or moves, the outrigger 40 has enough space for rotation or movement.

[0067] Such as Figure 7 shown, the outrigger 40 includes a connecting frame in the middle and lugs (the first lug 41 and the second lug 42) arranged at both ends of the connecting frame. The connecting frame can be arranged in a C shape, and the axes of the first lug 41 and the second lug 42 are parallel.

[0068] It should be noted that the arc surface of the outrigger 40 can be a perfectly smooth arc surface or an arc-shaped surface with corners; the overall thickness of its arc-shaped structure can remain the same, or there can be a change in thickness, that is, the thickness at the corner position or a certain arc-shaped position is thicker to provide the required support, and the thickness at a certain corner position or a certain arc-shaped position is thinner to adapt to the environmental requirements.

[0069] In an embodiment of the present utility model, as Figures 1 - 3 shown, a steering pulley 80 is provided on the support disk, so as to realize the relative flipping of the two support disks by means of wire drive or wire rope drive, thereby improving the rigidity of the joint; and a steering pulley 80 is provided on the support disk, which can place the motor at the rear, thereby reducing the joint inertia, and further improving the motion stability and safety of the joint.

[0070] An embodiment of the second aspect of the present utility model provides a robotic arm, and this robotic arm includes the three-degree-of-freedom joint provided in any embodiment.

[0071] The robotic arm provided by the embodiment of the present utility model has multiple legs 40 obliquely arranged between two support disks. The ends of the legs 40 are rotatably connected to the support disks through second connecting members. The second connecting members have two mutually perpendicular rotation axes. In this way, the two support disks can relatively flip, realizing the two-degree-of-freedom movement of pitching and yawing in space. The universal rotating shaft realizes the rolling-degree-of-freedom movement. Furthermore, the three-degree-of-freedom joint is extended to three degrees of freedom, so as to deflect in various angles in space to improve flexibility. And through the arrangement of the three legs, the stability of the two-degree-of-freedom movement is improved, thereby improving the stiffness and safety of the three-degree-of-freedom joint, and further improving the load capacity.

[0072] An embodiment of the third aspect of the present utility model provides a robot, which includes the three-degree-of-freedom joint provided by any embodiment, or includes the robotic arm provided by any embodiment.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present utility model, rather than to limit them. Although the present utility model has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features. And these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present utility model.

Claims

1. A three-degree-of-freedom joint, characterized in that: include: Two support plates are arranged opposite to each other at intervals; A universal shaft, both ends of which are arranged between the middle parts of the two support plates through a first connecting member, and the first connecting member has two rotation axes that are perpendicular to each other; A plurality of legs are obliquely arranged between the two support plates, and the plurality of legs are evenly distributed on the outer side of the universal shaft along the circumferential direction. The ends of the legs are connected to the support plates through a second connecting component, and the second connecting component has two rotation axes that are perpendicular to each other.

2. The three-degree-of-freedom joint according to claim 1, characterized in that: The universal joint shaft is in the shape of a straight rod, the first connecting component includes a rotating shaft, the rotating shaft has a first rotating shaft and a second rotating shaft arranged vertically, the first rotating shaft is rotatably connected to the end of the universal joint shaft, and the second rotating shaft is rotatably arranged in the middle of the supporting plate.

3. The three-degree-of-freedom joint according to claim 2, characterized in that: A rotating support is arranged in the middle of the supporting plate, the second rotating shaft is rotatably arranged on the rotating support, and the rotating axis of the rotating support is perpendicular to the rotating axis of the first rotating shaft and the rotating axis of the second rotating shaft.

4. The three-degree-of-freedom joint according to claim 3, characterized in that: The rotating support has a first transmission gear, the supporting plate has a second transmission gear meshing with the first transmission gear, and a steering pulley is arranged on the supporting plate.

5. The three-degree-of-freedom joint according to claim 2, characterized in that: The second connecting member comprises a transfer shaft, the transfer shaft having a first rotation shaft and a second rotation shaft which are vertically staggered, the first rotation shaft being rotationally connected to the end of the supporting leg, and the second rotation shaft being rotationally connected to the supporting plate; The rotation axes of the second rotation axes on the same side of the plurality of legs intersect with the central axis of the universal shaft.

6. The three-degree-of-freedom joint according to claim 5, characterized in that: The support plate has a shaft seat rotatably connected to the second rotating shaft, and the end of the support leg has a hanging ear rotatably connected to the first rotating shaft; One of the shaft seat and the second rotating shaft and the hanging ear and the first rotating shaft is a clearance fit, and the other of the shaft seat and the second rotating shaft and the hanging ear and the first rotating shaft is a tight fit.

7. The three-degree-of-freedom joint according to any one of claims 1 to 6, characterized in that: There are at least three supporting legs, and the diameter of a first circle formed by the first ends of the supporting legs is equal to the diameter of a second circle formed by the second ends of the supporting legs.

8. The three-degree-of-freedom joint according to claim 7, characterized in that: A projection of the first end of the leg on the support disk and a projection of the second end of the leg on the support disk have an offset distance, and the offset distance is equal to the diameter of the first circle.

9. A robotic arm, characterized in that: Comprising a three-degree-of-freedom joint as described in any one of claims 1 to 8.

10. A robot, characterized in that: It comprises a three-degree-of-freedom joint as described in any one of claims 1 to 8 or a robotic arm as described in claim 9.

Images