Thumb drive joint, robot hand and robot

Abstract

This application provides a thumb-driven joint, a robotic hand, and a robot. The thumb-driven joint includes a fixed component, a movable component, and a connecting bracket. The fixed component includes a first drive motor, a first output shaft, a first planetary gear reducer, and a bevel gear mechanism. The first planetary gear reducer includes a first housing and a multi-stage reducer. The bevel gear mechanism is connected to the multi-stage reducer and the first output shaft for transmission. The movable component is connected to the fingertip of the robotic hand. This application can eliminate the impact of impact forces on the thumb-driven joint, thereby improving the service life of the robotic hand.

Description

Technical Field

[0001] This application relates to the field of robotics, and more particularly to a thumb-driven joint, a robotic hand, and a robot. Background Technology

[0002] As an actuator capable of simulating human hand movements and performing operations such as grasping and handling, robotic arms are widely used in various fields such as industrial production, humanoid robots, and medical rehabilitation. Among them, the thumb, as the core component for achieving flexible grasping and precise manipulation, directly determines the overall working performance of the robotic arm through its motion flexibility, stability, and structural rationality.

[0003] The thumb drive joint is a key structure that controls the thumb to perform flexion, extension, and rotation movements. It typically includes a fixed component and a motion component. The core function of the fixed component is to establish a fixed connection with the palm part of the robotic hand, providing a mounting reference and support for the entire drive joint. The motion component is connected to the base of the thumb and is driven by power transmission to move the base of the thumb and the entire thumb to complete preset movements, thereby meeting the grasping and manipulation needs of the robotic hand.

[0004] In existing technologies, the power transmission from fixed components to moving components typically employs a worm gear structure. However, in practical applications, especially in humanoid robots, thumb-driven joints using worm gear structures are prone to collisions and interference with adjacent components such as the robot's waist and legs due to the complex posture changes and positional shifts that occur during humanoid robot movement. Such collisions directly impact the thumb of the robotic hand, and the counter-drive force of the worm gear structure amplifies this impact force, causing the impact energy to be directly transmitted to the thumb's drive joint and the thumb itself. This increases the risk of thumb damage and shortens the lifespan of the robotic hand. Summary of the Invention

[0005] This application discloses a thumb-driven joint, a robotic hand, and a robot, which can eliminate the impact of impact forces on the thumb-driven joint, thereby improving the service life of the robotic hand.

[0006] To achieve the above objectives, this application discloses a thumb-driven joint, comprising: A fixing component for connection to the palm of a robotic arm, the fixing component comprising: First drive motor; First output axis; A first planetary gear reducer, comprising: First outer shell; Multi-stage reducer; A bevel gear mechanism, wherein the bevel gear mechanism is drively connected to the multi-stage reducer and the first output shaft; An active component for connecting to the fingertips of the robotic arm; A connecting bracket, the first end of which is fixedly connected to the first output shaft and the second end of which is connected to the movable component, so as to drive the movable component to swing around the first output shaft.

[0007] In one possible implementation, the multi-stage reducer includes a first reduction assembly, a second reduction assembly, and a third reduction assembly. Each of the first, second, and third reduction assemblies includes a first sun gear, a plurality of first planet gears, a first internal gear ring, and a first planet carrier, all disposed within the first housing. The first sun gear meshes with the plurality of first planet gears, the plurality of first planet gears mesh with the first internal gear ring, the first internal gear ring is fixedly connected to the first housing, and the first planet carrier is connected to each of the plurality of first planet gears. The first sun gear of the first reduction assembly is fixedly connected to the output end of the first drive motor, and the first planet carrier is fixedly connected to the first sun gear of the second reduction assembly. The first planet carrier of the second reduction assembly is fixedly connected to the first sun gear of the third reduction assembly. The first planet carrier and the first output shaft of the third reduction assembly are both connected to the bevel gear mechanism.

[0008] In one possible implementation, the first planetary carrier is provided with a plurality of planetary fixed shafts, each of which corresponds to a plurality of the first planetary gears, and the first planetary gears are rotatably mounted on the planetary fixed shafts.

[0009] In one possible implementation, the bevel gear mechanism includes: A drive shaft, one end of which is fixedly connected to the first planetary carrier of the third reduction assembly; The first bevel tooth is fixedly connected to the drive shaft; The second bevel tooth meshes with the first bevel tooth, and the rotation axis of the second bevel tooth is perpendicular to the rotation axis of the first bevel tooth, while the rotation axis of the second bevel tooth is parallel to the extension direction of the first output shaft.

[0010] In one possible implementation, the outer peripheral walls at both ends of the first output shaft are provided with a first flat section; The first end of the connecting bracket has two first connecting ears, each of which has a first connecting hole. A second flat part corresponding to the first flat part is provided in the first connecting hole. The two ends of the drive shaft are respectively inserted into the two first connecting holes, and the first flat part and the second flat part cooperate.

[0011] In one possible implementation, the second reduction assembly includes two sets, with the first planetary carrier of one set of the third reduction assembly fixedly connected to the first sun gear of the other set of the second reduction assembly.

[0012] In one possible implementation, the activity component includes: Second drive motor; The second planetary gear reducer is connected to the second drive motor in a transmission manner; A worm gear mechanism is connected to the second planetary gear reducer, and the module of the worm gear is 0.6 mm. The second output shaft is connected to the worm gear transmission and is also connected to the second end of the connecting bracket.

[0013] In one possible implementation, the extension direction of the second output shaft is perpendicular to the extension direction of the first output shaft.

[0014] In one possible implementation, the second planetary gear reducer includes: The second housing contains a second sun gear, multiple second planet gears, a second internal gear ring, and a second planet carrier. The second sun gear is fixedly connected to the output end of the second drive motor. The second sun gear also meshes with multiple second planet gears. The multiple second planet gears mesh with the second internal gear ring. The second internal gear ring is fixedly connected to the second housing. The second planet carrier is connected to multiple second planet gears respectively. The second planet carrier is also connected to the worm gear drive.

[0015] In one possible implementation, the worm gear mechanism includes a turbine housing, a worm rotatably mounted on the turbine housing, and a turbine meshing with the worm. The worm is fixedly connected to the second planetary carrier, and the turbine is located inside the turbine housing and fixedly connected to the second output shaft. The thumb drive joint also includes a backlash-free tension spring connected between the turbine housing and the fixing assembly, for causing the worm to move closer to the turbine.

[0016] Secondly, this application also provides a robotic hand, including the thumb-driven joint described in the first aspect.

[0017] Thirdly, this application also provides a robot, including the robotic arm described in the second aspect.

[0018] Compared with the prior art, the beneficial effects of this application are as follows: Since the bevel gear mechanism is connected to the multi-stage reducer, the bevel gear mechanism adopts a bevel gear meshing transmission method, which can realize 90° steering transmission of power. There is no need to reserve additional radial installation space for worm gear transmission, which further optimizes the spatial layout of the fixed components and makes the overall structure of the fixed components more flat.

[0019] On the other hand, the novel transmission scheme employing a first planetary gear reducer and a bevel gear mechanism has a transmission principle that determines that the reverse driving force is much smaller than that of a worm gear structure. Even under special working conditions, when a slight external force is generated, the meshing structure of the first planetary gear reducer can effectively disperse the force, preventing the force from being amplified in the transmission chain and avoiding impact damage to the internal components of the drive joint and the thumb body. Furthermore, the bevel gear mechanism has a small meshing transmission clearance, high power transmission efficiency, and low recoil force. When combined with the first planetary gear reducer, it forms a low-reverse-drive transmission chain, eliminating the technical defect of high reverse driving force from the perspective of transmission structure. This significantly improves the impact resistance of the thumb drive joint, effectively reduces the risk of wear and deformation of internal components, and significantly extends the overall service life of the thumb and its drive joint, thereby improving the service life and operational reliability of the robotic arm. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is an assembly diagram of the thumb-driven joint provided in an embodiment of this application; Figure 2 This is an exploded view of the thumb-driven joint provided in an embodiment of this application; Figure 3 This is a three-dimensional diagram of the fixing component provided in the embodiments of this application; Figure 4 This is a side view of the fixing component provided in an embodiment of this application; Figure 5 yes Figure 4 Cross-sectional view at point AA; Figure 6 This is a schematic diagram of the structure of the connecting bracket provided in an embodiment of this application; Figure 7 This is a three-dimensional diagram of the active component provided in the embodiments of this application; Figure 8 This is a side view of the active component provided in the embodiments of this application; Figure 9 yes Figure 8 Cross-sectional view at point BB; Figure 10 This is a rear view of the active component provided in the embodiments of this application; Figure 11 yes Figure 10 Cross-sectional view at point CC.

[0022] Explanation of reference numerals in the attached figures: 100-Thumb-driven joint; 110-Fixed assembly; 111-First drive motor; 112-First output shaft; 113-First planetary gear reducer; 1131-First housing; 1132-First reduction assembly; 1133-Second reduction assembly; 1134-Third reduction assembly; 113a-First sun gear; 113b-First planet gear; 113d-First planet carrier; 114-Bevel gear mechanism; 1141-Drive shaft; 1142-First bevel gear; 1143-Second bevel gear; 115-First support; 116-First rolling bearing; 117-Second rolling bearing; 120 - Moving component; 121 - Second drive motor; 122 - Second planetary gear reducer; 1221 - Second housing; 1222 - Second sun gear; 1223 - Second planetary gear; 1224 - Second planetary carrier; 123 - Worm gear mechanism; 1231 - Turbine; 1232 - Worm; 1233 - Turbine housing; 124 - Second output shaft; 130 - Connecting bracket; 131 - First connecting ear; 140 - Backlash-free tension spring. Detailed Implementation

[0023] 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. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0024] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0025] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0026] Furthermore, the terms "installation," "setup," "equipped with," "connection," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0027] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, components, or parts (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, components, or parts. Unless otherwise stated, "a plurality of" means two or more.

[0028] The technical solution of this application will be further described below with reference to specific embodiments and accompanying drawings.

[0029] See Figures 1 to 4This application provides a thumb-driven joint 100, which includes a fixed component 110, a movable component 120, and a connecting bracket 130. The fixed component 110 is used to connect with the palm of a robotic hand. The fixed component 110 includes a first drive motor 111, a first output shaft 112, a first planetary gear reducer 113, and a bevel gear mechanism 114. The first planetary gear reducer 113 includes a first housing 1131 and a multi-stage reducer. The multi-stage reducer includes a first reduction component 1132, a second reduction component 1133, and a third reduction component 1134. The first reduction component 1132, the second reduction component 1133, and the third reduction component 1134 each include a first sun gear 113a, a plurality of first planetary gears 113b, a first internal gear ring, and a first planet carrier 113d disposed within the first housing 1131. The first sun gear 113a and the plurality of first planetary gears 113b are... The first planetary gears 113b mesh with the first internal gear ring, which is fixedly connected to the first housing 1131. The first planetary carrier 113d is connected to the first planetary gears 113b respectively. The first sun gear 113a of the first reduction assembly 1132 is fixedly connected to the output end of the first drive motor 111. The first planetary carrier 113d is fixedly connected to the first sun gear of the second reduction assembly 1133. The first planetary carrier 113d of the second reduction assembly 1133 is fixedly connected to the first sun gear of the third reduction assembly 1134. The bevel gear mechanism 114 is connected to the first planetary carrier 113d and the first output shaft 112 of the third reduction assembly 1134 respectively. The movable component 120 is used to connect with the fingertips of the robot. The first end of the connecting bracket 130 is fixedly connected to the first output shaft 112, and the second end is connected to the movable component 120 to drive the movable component 120 to swing around the first output shaft 112.

[0030] The aforementioned thumb-driven joint 100 can be applied to general industrial robotic arms and humanoid robotic arms.

[0031] The aforementioned plurality of first planetary gears 113b may be two, three, or four first planetary gears 113b, and the plurality of first planetary gears 113b are distributed at equal intervals around the first sun gear 113a.

[0032] The axis of the first output shaft 112 is perpendicular to the palm and also perpendicular to the rotation center of the first sun gear 113a. Figure 5 The direction indicated by the x-arrow.

[0033] Since the first sun gear 113a of the first reduction assembly 1132 is fixedly connected to the output end of the first drive motor 111, the first planetary carrier 113d is fixedly connected to the first sun gear of the second reduction assembly 1133, the first planetary carrier 113d of the second reduction assembly 1133 is fixedly connected to the first sun gear of the third reduction assembly 1134, and the bevel gear mechanism 114 is respectively connected to the first planetary carrier 113d and the first output shaft 112 of the third reduction assembly 1134, on the one hand, the multi-stage reducers are driven sequentially in a coaxial series manner, which improves the structural compactness of the fixed assembly 110 in the direction of the rotation axis of the first sun gear. Compared with the radially unfolded installation of the worm gear, the height of the fixed assembly 110 in the direction of the rotation axis of the first sun gear is greatly reduced. On the other hand, the bevel gear mechanism 114 adopts a bevel gear meshing transmission method, which can realize the 90° steering transmission of power. There is no need to reserve additional radial installation space for the worm gear transmission, which further optimizes the spatial layout of the fixed assembly 110 and makes the overall structure of the fixed assembly 110 more flat.

[0034] On the other hand, a novel transmission scheme employing a first planetary gear reducer 113 and a bevel gear mechanism 114 is used. The first planetary gear reducer 113 is an internal meshing transmission of a fixed-axis gear train. The first internal gear ring is fixedly connected to the first housing 1131. Power is transmitted sequentially through the first sun gear 113a, the first planetary gears 113b, and the first planetary carrier 113d. Its transmission principle determines that the reverse driving force is much smaller than that of the worm gear mechanism 123. Even under special working conditions, when a slight external force is generated, the meshing structure of the first planetary gear reducer 113 can effectively disperse the force and avoid damage. The force is amplified in the transmission chain, preventing impact damage to the internal components of the drive joint and the thumb itself. Furthermore, the bevel gear mechanism 114 has a small meshing transmission clearance, high power transmission efficiency, and low recoil force. It works in conjunction with the first planetary gear reducer 113 to form a low-reverse-drive transmission chain, eliminating the technical defect of high reverse drive force from the transmission structure level. This significantly improves the impact resistance of the thumb drive joint 100, effectively reduces the risk of wear and deformation of internal components, and significantly extends the overall service life of the thumb and its drive joint, thereby improving the service life and operational reliability of the robot.

[0035] In some possible embodiments, a plurality of planetary fixed shafts are provided on the first planetary carrier 113d, and the plurality of planetary fixed shafts correspond one-to-one with a plurality of first planetary gears 113b, the first planetary gears 113b being rotatably mounted on the planetary fixed shafts.

[0036] Since multiple planetary fixed shafts correspond one-to-one with multiple first planetary gears 113b, and the first planetary gears 113b are rotatably mounted on the planetary fixed shafts, each first planetary gear 113b is supported by an independent planetary fixed shaft. This design allows multiple first planetary gears 113b to evenly bear the power load transmitted by the first sun gear 113a and smoothly distribute the load to the first internal gear ring and the first planetary carrier 113d, avoiding the problem of load concentration on one or a few planetary gears due to the failure of the support of the first planetary gear 113b. At the same time, the planetary fixed shafts provide rigid radial support for the first planetary gears 113b, which can effectively resist the radial force brought by the transmission process or external impact, improve the overall load-bearing capacity and impact resistance of the single reduction assembly, and, together with the design of the first planetary gear reducer 113 replacing the worm gear structure, further reduce the damage of external forces to the transmission structure, extend the service life of the first planetary gear reducer 113, and indirectly reduce the overall damage rate of the thumb drive joint 100.

[0037] In some possible embodiments, see Figure 5 The bevel gear mechanism 114 includes a drive shaft 1141, a first bevel gear 1142, and a second bevel gear 1143. One end of the drive shaft 1141 is fixedly connected to the first planetary carrier 113d of the third reduction assembly 1134. The first bevel gear 1142 is fixedly connected to the drive shaft 1141. The second bevel gear 1143 meshes with the first bevel gear 1142, and the rotation axis of the second bevel gear 1143 is perpendicular to the rotation axis of the first bevel gear 1142. The rotation axis of the second bevel gear 1143 is parallel to the extension direction of the first output shaft 112.

[0038] Since the second bevel tooth 1143 meshes with the first bevel tooth 1142, and the rotation axis of the second bevel tooth 1143 is perpendicular to the rotation axis of the first bevel tooth 1142, the power output by the first planetary gear reducer 113 can be transmitted along the "drive shaft 1141-first bevel tooth 1142-second bevel tooth 1143", achieving a 90° deviation-free power steering of the first planetary gear reducer 113. Thus, there is no need to add additional steering auxiliary components, directly matching the movement trajectory of the thumb swinging around the first output shaft 112, allowing the low-speed, high-torque power output by the first drive motor 111 to be accurately transmitted to the first output shaft 112. This ensures that the power transmission direction of the second bevel tooth 1143 is highly compatible with the thumb's movement requirements, improving the adaptability of the power transmission of the entire thumb drive joint 100.

[0039] It should be noted that the ratio of the number of teeth of the first bevel tooth 1142 and the second bevel tooth 1143 can be 1:1 or other ratios such as 2:1 or 2:3, and the first bevel tooth 1142 and the second bevel tooth 1143 can be spur gears or helical gears.

[0040] Optional, see Figure 5 The fixing assembly 110 also includes a bracket 115 connected to the first housing 1131, a drive shaft 1141 rotatably connected to the bracket 115 via a first rolling bearing 116, and a first output shaft 112 rotatably connected to the bracket 115 via a second rolling bearing 117.

[0041] In some possible embodiments, see Figure 6 The outer peripheral walls of both ends of the first output shaft 112 are provided with first flat positions. The first end of the connecting bracket 130 forms two first connecting ears 131. Each of the two first connecting ears 131 is provided with a first connecting hole. A second flat position corresponding to the first flat position is provided in the first connecting hole. Both ends of the first output shaft 112 are respectively inserted into the two first connecting holes, and the first flat position and the second flat position cooperate.

[0042] By engaging the first flat part and the second flat part, a rigid circumferential anti-rotation constraint is formed between the first output shaft 112 and the first connecting hole, which completely restricts the relative circumferential rotation between the two. This allows the torque of the first output shaft 112 to be transmitted directly and without loss to the connecting bracket 130 through the mating surfaces of the first flat part and the second flat part. The connecting bracket 130 then drives the movable component 120 and the thumb heel to move.

[0043] On the other hand, it can achieve complete synchronization between the rotation of the first output shaft 112 and the swing of the connecting bracket 130. Every rotation angle of the first output shaft 112 can be accurately transmitted to the connecting bracket 130, completely eliminating the idle stroke and transmission lag of conventional cooperation, ensuring that the swing angle of the thumb is highly consistent with the control command of the first drive motor 111, greatly improving the angle accuracy and motion synchronization of the thumb movement, and enabling the thumb of the robotic arm to complete more precise grasping and positioning operations.

[0044] The first flat position can be one plane or multiple planes. When the first flat position is multiple planes, the multiple planes are evenly distributed along the rotation axis of the first output shaft 112.

[0045] In some possible embodiments, see Figure 5 The second reduction assembly 1133 includes two sets, with the first planet carrier 113d of one set of the second reduction assembly 1133 being fixedly connected to the first sun gear of the other set of the second reduction assembly 1133.

[0046] In the above-mentioned fixed connection between the first planetary carrier 113d of the second reduction assembly 1133 and the first sun gear of the other set of second reduction assemblies 1133, there are various structures in which the first sun gear and the first planetary carrier 113d are fixedly connected. For example, the first sun gear is welded to the first planetary carrier 113d, or the first planetary carrier 113d is provided with a mounting hole, and one end of the first sun gear is interference-fitted into the mounting hole.

[0047] The second reduction assembly 1133 comprises two sets, which can add a second reduction assembly 1133 of the same specification to the original three-stage reduction of "first reduction assembly 1132, second reduction assembly 1133 and third reduction assembly 1134", forming a four-stage planetary reduction transmission link. After the power is reduced by four stages, the reduction ratio is greatly improved. The reduction ratio is the product of the reduction ratios of each stage of the reduction assembly. Thus, the high-speed low-torque power of the first drive motor 111 can be efficiently converted into ultra-low-speed high-torque power. The output torque is much higher than that of the conventional three-stage planetary reduction structure, which is suitable for the power requirements of various operations of the robotic thumb.

[0048] In some possible embodiments, see Figures 7 to 11 The active component 120 includes a second drive motor 121, a second planetary gear reducer 122, a worm gear mechanism 123, and a second output shaft 124. The second planetary gear reducer 122 is driven by the second drive motor 121; the worm gear mechanism 123 is driven by the second planetary gear reducer 122, and the module of the worm gear mechanism 123 is 0.6mm; the second output shaft 124 is driven by the worm gear mechanism 123, and the second output shaft 124 is connected to the second end of the connecting bracket 130.

[0049] Based on the above embodiments, it can be seen that the movable component 120 is independently driven by the second drive motor 121, and the power is transmitted through the second planetary gear reducer 122, the worm gear mechanism 123 and the second output shaft 124, thereby driving the thumb to complete the flexion / extension / rotation action around the second output shaft 124. Furthermore, the cooperation between the fixed component 110 and the movable component 120 can realize the multi-degree-of-freedom compound motion of the thumb, thereby allowing the robot thumb to simulate the flexible movement of the human hand, adapting to the grasping needs of workpieces of different shapes and sizes, and greatly improving the grasping flexibility and operational adaptability of the robot.

[0050] Furthermore, the second planetary gear reducer 122 in the active component 120 will first reduce the power of the second drive motor 121 by initially reducing the speed and increasing the torque, and then convert the high-speed, low-torque power into medium-speed, medium-torque power, which is then transmitted to the worm gear mechanism 123. The worm gear mechanism 123 achieves secondary speed reduction and torque increase, further improving the output torque and accurately matching the power requirements of the thumb's local movement. On the other hand, it utilizes the meshing characteristics of the worm gear mechanism 123 to achieve power reversal / self-locking, adapting to the trajectory direction of the thumb's local movement. At the same time, the self-locking function of the worm gear mechanism 123 allows the thumb to maintain a preset posture after grasping, without the need for continuous power supply, thus reducing energy consumption.

[0051] In addition, by setting the module of the worm gear mechanism 123 to 0.6mm, on the one hand, the tooth size of the 0.6mm module is moderate, which can achieve a compact design of the worm gear mechanism 123 within the miniaturized layout of the movable component 120, and will not cause the thumb volume to increase due to the excessive size of the component, or cause motion interference. On the other hand, compared with a smaller module, the tooth thickness and root circle diameter of the 0.6mm module are larger, which greatly improves the structural strength and impact resistance of the teeth, can effectively bear the torque transmitted by the second planetary gear reducer 122, and avoid damage such as bending and tooth breakage of the teeth due to excessive force, thus ensuring the transmission reliability of the worm gear mechanism 123.

[0052] It should be noted that the axis of the second output shaft 124 is parallel to the palm, and the base of the thumb can bend around the second output shaft 124 to achieve the grasping motion.

[0053] Optionally, the second output shaft 124 is connected to the second end of the connecting bracket 130 via a flat section.

[0054] In some possible embodiments, the extension direction of the second output shaft 124 is perpendicular to the extension direction of the first output shaft 112.

[0055] Since the first output shaft 112 is the power output end of the fixed component 110 and the second output shaft 124 is the power output end of the movable component 120, and the extension direction of the second output shaft 124 is perpendicular to the extension direction of the first output shaft 112, a spatially orthogonal two-degree-of-freedom motion system is formed between the first output shaft 112 and the second output shaft 124, which accurately replicates the bionic motion trajectory of the human thumb.

[0056] In some possible embodiments, see Figure 9 and Figure 11The second planetary gear reducer 122 includes a second housing 1221. Inside the second housing 1221, there is a second sun gear 1222, a plurality of second planet gears 1223, a second internal gear ring, and a second planet carrier 1224. The second sun gear 1222 is fixedly connected to the output end of the second drive motor 121. The second sun gear 1222 also meshes with the plurality of second planet gears 1223. The plurality of second planet gears 1223 mesh with the second internal gear ring. The second internal gear ring is fixedly connected to the second housing 1221. The second planet carrier 1224 is connected to the plurality of second planet gears 1223 respectively. The second planet carrier 1224 is also connected to the worm gear mechanism 123 for transmission.

[0057] Therefore, in this embodiment, the second planetary gear reducer 122 has an internal meshing coaxial layout. The second sun gear 1222 and multiple second planetary gears 1223 are integrated into the closed cavity formed by the second internal gear ring and the second housing 1221. All transmission components are stacked along the axial direction of the second drive motor 121, without any radially outward-extending transmission structure, which significantly reduces the overall volume and radial dimensions of the reducer. At the same time, the power input second sun gear 1222 and the power output second planetary carrier 1224 of the second planetary gear reducer 122 are coaxially designed, which can directly connect axially with the second drive motor 121 and the worm gear mechanism 123 without additional steering or transition components. This further simplifies the transmission link layout of the moving component 120, allowing the second planetary gear reducer 122 to be perfectly embedded in the local installation space of the thumb, taking into account both transmission function and miniaturization design requirements, and avoiding interference with thumb movement due to excessive component size.

[0058] Additionally, it should be noted that the second sun gear 1222, multiple second planet gears 1223, the second internal gear ring, and the second planet carrier 1224 form a component, and this component can be one, two, three, etc.

[0059] In some possible embodiments, see Figure 2 and Figure 11 The worm gear mechanism 123 includes a turbine housing 1233, a worm 1232 rotatably mounted on the turbine housing 1233, and a turbine 1231 meshing with the worm 1232. The worm 1232 is fixedly connected to the second planetary carrier 1224, and the turbine 1231 is located inside the turbine housing 1233 and fixedly connected to the second output shaft 124. The thumb drive joint 100 also includes a backlash-free tension spring 140, which is connected between the turbine housing 1233 and the fixing assembly 110 to allow the worm 1232 to move closer to the turbine 1231.

[0060] After machining and assembly, the worm gear mechanism 123 inevitably has a small inherent gap on the meshing surface. This gap will further increase due to normal wear of the gear teeth over long-term operation. Conventional worm gear mechanisms 123 lack a backlash elimination structure. This gap causes the worm gear 1232 to rotate a certain angle before the turbine 1231 follows suit, resulting in lag in thumb movements and positioning deviations, severely affecting the precision of fine operation. Simultaneously, the gap causes impact meshing of the gear teeth during power transmission, leading to vibration and noise. Therefore, a backlash elimination spring 140 is installed between the turbine housing 1233 and the fixed assembly 110. The continuous elastic tension of the backlash elimination spring 140 pulls the turbine housing 1233, causing the worm gear 1232, which is rotatably connected to the turbine housing 1233, to always be pressed against the turbine 1231. The elastic preload actively eliminates all meshing gaps between the worm gear 1232 and the turbine 1231, ensuring that their meshing surfaces remain in a tight, gapless fit.

[0061] Therefore, by setting the backlash-free tension spring 140, the transmission backlash problem of the worm gear mechanism 123 is solved from the root, realizing the backlash-free synchronous transmission between the worm 1232 and the turbine 1231. Every angle of rotation of the worm 1232 can be directly transmitted to the turbine 1231, avoiding action lag and positioning deviation, greatly improving the transmission accuracy of the moving component 120, making the local flexion / extension / rotation of the thumb more precise, and improving the stability of thumb movement.

[0062] This application also provides a robotic hand, which includes the thumb-driven joint 100 in the above embodiments.

[0063] The structure and function of the thumb-driven joint 100 in this embodiment are the same as those in the above embodiments, and can be referred to the above content, so they will not be repeated here.

[0064] Because the robotic arm uses the thumb-driven joint 100 in the above embodiment, the service life of the robotic arm can be improved.

[0065] It should be noted that robotic arms can be humanoid robotic arms, industrial robotic arms, special operation robotic arms, etc., and can be applied to humanoid robots, service robots, bionic robots, etc.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A thumb-driven joint (100), characterized in that, include: A fixing component (110) for connection to the palm of a robotic arm, the fixing component (110) comprising: First drive motor (111); First output shaft (112); A first planetary gear reducer (113) includes: First outer shell (1131); Multi-stage reducer; A bevel gear mechanism (114) is connected to the multi-stage reducer and the first output shaft (112) respectively. An active component (120) is provided for connection to the fingertips of the robotic arm; A connecting bracket (130) is provided, with its first end fixedly connected to the first output shaft (112) and its second end connected to the movable component (120) to drive the movable component (120) to swing around the first output shaft (112).

2. The thumb-driven joint (100) according to claim 1, characterized in that, The multi-stage reducer includes a first reduction assembly (1132), a second reduction assembly (1133), and a third reduction assembly (1134). Each of these three components includes a first sun gear (113a), a plurality of first planet gears (113b), a first internal gear ring, and a first planet carrier (113d), all disposed within the first housing (1131). The first sun gear (113a) meshes with the plurality of first planet gears (113b), and the plurality of first planet gears (113b) mesh with the first internal gear ring. The first internal gear ring is fixed to the first housing (1131). The first planetary carrier (113d) is connected to a plurality of first planetary gears (113b) respectively. The first sun gear (113a) of the first reduction assembly (1132) is fixedly connected to the output end of the first drive motor (111). The first planetary carrier (113d) is fixedly connected to the first sun gear of the second reduction assembly (1133). The first planetary carrier (113d) of the second reduction assembly (1133) is fixedly connected to the first sun gear of the third reduction assembly (1134). The first planetary carrier (113d) and the first output shaft (112) of the third reduction assembly (1134) are both connected to the bevel gear mechanism (114) for transmission.

3. The thumb-driven joint (100) according to claim 2, characterized in that, The first planetary carrier (113d) is provided with a plurality of planetary fixed shafts, and the plurality of planetary fixed shafts correspond one-to-one with a plurality of first planetary gears (113b). The first planetary gears (113b) are rotatably mounted on the planetary fixed shafts.

4. The thumb-driven joint (100) according to claim 2, characterized in that, The bevel gear mechanism (114) includes: A drive shaft (1141), one end of which is fixedly connected to the first planetary carrier (113d) of the third reduction assembly (1134); The first bevel tooth (1142) is fixedly connected to the drive shaft (1141); The second bevel tooth (1143) meshes with the first bevel tooth (1142), and the rotation axis of the second bevel tooth (1143) is perpendicular to the rotation axis of the first bevel tooth (1142), and the rotation axis of the second bevel tooth (1143) is parallel to the extension direction of the first output shaft (112).

5. The thumb-driven joint (100) according to claim 4, characterized in that, The outer peripheral walls at both ends of the first output shaft (112) are provided with first flat sections; The first end of the connecting bracket (130) forms two first connecting ears (131), each of the two first connecting ears (131) is provided with a first connecting hole, and a second flat part corresponding to the first flat part is provided in the first connecting hole. The two ends of the drive shaft (1141) are respectively inserted into the two first connecting holes, and the first flat part and the second flat part cooperate.

6. The thumb-driven joint (100) according to claim 2, characterized in that, The second reduction assembly (1133) includes two sets, one set of which has its first planet carrier (113d) fixedly connected to the other set of which has its first sun gear.

7. The thumb-driven joint (100) according to claim 1, characterized in that, The active component (120) includes: Second drive motor (121); The second planetary gear reducer (122) is connected to the second drive motor (121) in a transmission connection. A worm gear mechanism (123) is connected to the second planetary gear reducer (122) in a transmission connection. The second output shaft (124) is connected to the worm gear mechanism (123) and is connected to the second end of the connecting bracket (130).

8. The thumb-driven joint (100) according to claim 7, characterized in that, The extension direction of the second output shaft (124) is perpendicular to the extension direction of the first output shaft (112).

9. The thumb-driven joint (100) according to claim 7, characterized in that, The second planetary gear reducer (122) includes: The second housing (1221) contains a second sun gear (1222), a plurality of second planet gears (1223), a second internal gear ring, and a second planet carrier (1224). The second sun gear (1222) is fixedly connected to the output end of the second drive motor (121). The second sun gear (1222) also meshes with the plurality of second planet gears (1223). The plurality of second planet gears (1223) mesh with the second internal gear ring. The second internal gear ring is fixedly connected to the second housing (1221). The second planet carrier (1224) is connected to the plurality of second planet gears (1223) respectively. The second planet carrier (1224) is also connected to the worm gear mechanism (123) for transmission.

10. The thumb-driven joint (100) according to claim 9, characterized in that, The worm gear mechanism (123) includes a turbine housing (1233), a worm (1232) rotatably mounted on the turbine housing (1233), and a turbine (1231) meshing with the worm (1232). The worm (1232) is fixedly connected to the second planetary carrier (1224), and the turbine (1231) is located inside the turbine housing (1233) and fixedly connected to the second output shaft (124). The thumb drive joint (100) also includes a backlash-free tension spring (140) connected between the turbine housing (1233) and the fixing assembly (110) for moving the worm (1232) closer to the turbine (1231).

11. A robotic arm, characterized in that, Includes the thumb-driven joint (100) as described in any one of claims 1-10.

12. A robot, characterized in that, Including the robotic arm as described in claim 11.

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