Speed reducer based on duplex planetary gear, driving device and dexterous hand

Abstract

The embodiment of the invention relates to the technical field of robots, and discloses a speed reducer based on a duplex planetary gear, a driving device and a dexterous hand. According to the invention, the tooth number difference design of the duplex planetary gear and the inner gear is adopted, so that the graded speed reduction effect is realized, and the high-speed low-torque output of the motor is effectively converted into low-speed high-torque output. In addition, by means of the integrated single planet carrier fixing mode, the duplex planet gear achieves autorotation and revolution in the integrated structure, the number of parts is reduced, clearance configuration is simplified, and therefore the internal space is effectively compressed. And finally, a roller transmission structure is arranged between the second inner gear and the shell to replace a traditional bearing, and the size and the weight of the whole structure are further reduced while torque output stability is ensured by omitting inner and outer ring components.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of robotics, and in particular to a reducer, a drive device and a dexterous hand based on double planetary gears. Background Art

[0002] The reducer is a key transmission component in various mechanical and robotic systems. It is widely used in industrial automation, service robots, aerospace, medical equipment and other fields that require high-precision and high-performance transmission. It can convert the high-speed, low-torque output of the motor into low-speed, high-torque output, thereby meeting the needs of a variety of applications for large torque and precise motion control. In some systems that are sensitive to size and weight, the reducer must also achieve a compact and lightweight structural design as much as possible.

[0003] Related reducer technologies usually include planetary reducers, harmonic reducers, RV reducers, etc. However, these types of traditional gear transmission structures are difficult to achieve high reduction ratios while taking into account small size and low weight, which limits their application in scenarios that are highly sensitive to space and weight. Summary of the invention

[0004] The purpose of the embodiments of the present invention is to provide a reducer, a drive device and a dexterous hand based on a double planetary gear, so as to meet the requirements of high reduction ratio, small volume and low weight.

[0005] To solve the above technical problems, an embodiment of the present invention provides a reducer based on a double-coupled planetary gear, comprising: a sun gear, used to transmit external torque to the inside of the reducer; at least one double-coupled planetary gear, including a first planetary gear and a second planetary gear, wherein the first planetary gear is meshed with the sun gear, and the number of teeth of the first planetary gear is greater than that of the second planetary gear; a planet carrier, used to fix the double-coupled planetary gear on an orbital trajectory, comprising a first mounting surface and a second mounting surface, the first mounting surface is used to assemble the first planetary gear, and the second mounting surface is used to install the second planetary gear; a first internal gear, meshed with the first planetary gear; a second internal gear, meshed with the second planetary gear, and realizing turnover with the outer casing through a roller transmission structure, and used to output the torque of the second planetary gear, and the number of teeth of the first internal gear is greater than that of the second internal gear.

[0006] An embodiment of the present invention also provides a driving device, comprising a reducer based on a double planetary gear as described above, and a drive motor; the drive motor is used to input a rotational torque to the reducer; the reducer is used to receive the torque input by the drive motor and output the torque to the outside after decelerating the input torque inside the reducer.

[0007] An embodiment of the present invention further provides a dexterous hand, comprising the driving device as described above, and realizing joint operation based on the torque output by the driving device.

[0008] In the embodiment of the present invention, the differential design of the number of teeth of the double planetary gear and the internal gear is adopted to achieve a graded deceleration effect, effectively converting the high-speed and low-torque output of the motor into low-speed and high-torque. In addition, the integrated single planetary carrier fixing method enables the double planetary gear to realize rotation and revolution in an integrated structure, simplifying the number of parts and gap configuration, thereby effectively compressing the internal space. Finally, a roller transmission structure is set between the second internal gear and the outer shell to replace the traditional bearing. By eliminating the inner and outer ring components, the size and weight of the overall structure are further reduced while ensuring the stability of the torque output. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0010] Figure 1 is a schematic diagram of the overall structure of the reducer provided in an embodiment of the present application;

[0011] Figure 2 is a schematic cross-sectional view of a reducer provided in an embodiment of the present application along one direction;

[0012] Figure 3 is a cross-sectional schematic diagram of the reducer provided in an embodiment of the present application along another direction;

[0013] Figure 4 It is a structural schematic diagram of a side surface of a reducer provided in an embodiment of the present application;

[0014] Figure 5 is a schematic diagram of the overall structure of the driving device provided in an embodiment of the present application;

[0015] Figure 6 is a structural schematic diagram of one side of a driving device provided in an embodiment of the present application;

[0016] Figure 7 A schematic cross-sectional view of a driving device along one direction provided in an embodiment of the present application.

[0017] Among them, the reference numerals include: input shaft 1, sun gear 2, first internal gear 3, first planetary gear 4, second planetary gear 5, second internal gear 6, planet carrier 7, output shaft 8, roller 9, housing 10, drive motor 11, connecting flange 12, reducer housing 13, output synchronous gear 14. DETAILED DESCRIPTION

[0018] Reducers are essential transmission components in mechanical and robotic systems, and are widely used in industrial automation, service robots, aerospace, medical equipment, and other fields, especially in situations where precise control and high-load transmission are required. The main function of a reducer is to convert the high-speed, low-torque output of a motor into a low-speed, high-torque output to meet the needs of high-torque and high-precision motion control. In many applications, especially in robotics, reducers not only have to carry high torque, but also need to have a compact and lightweight structural design to adapt to space-constrained, weight-sensitive working environments.

[0019] While reducers are widely used, they also need to meet a series of complex design requirements according to different application scenarios. For example, in the field of industrial automation, reducers are usually used to drive robot arms, transmission systems, precision processing machinery, etc., and need to ensure high load, high precision and long-term stable operation. In the fields of aerospace and medical equipment, reducers need to have a small size and weight, while carrying a large torque to adapt to harsh working environments. In the field of service robots, reducers must not only provide stable power transmission, but also have a high reduction ratio to ensure flexible motion control and long working time.

[0020] Among them, robot end effectors, such as robot arms and dexterous hands, particularly require high-precision motion control and high torque output. In such applications, the size, weight and reduction ratio of the reducer become key factors because they directly affect the robot's ability and efficiency to perform tasks. Especially in micro robots and precision surgical robots, the reducer not only needs to provide precise force control and motion accuracy, but also must meet extremely small volume and weight requirements.

[0021] Existing reducer technologies, including planetary reducers, harmonic reducers, and RV reducers, have been widely used in various mechanical and robotic systems, but they still have certain limitations in certain application scenarios:

[0022] Planetary reducer: Planetary reducer is widely used for its simple structure and high efficiency. It is mainly composed of sun gear, planetary gear and internal gear. The central sun gear is generally the input gear. The planetary gear rotates around the sun gear and rotates on its own at the same time. The internal gear meshes with the planetary gear, and the planetary gear drives the planetary carrier to rotate, and finally the power is output through the rotation of the planetary carrier. However, the reduction ratio of the planetary reducer is generally small (usually less than 100:1). To further increase the reduction ratio, the size and weight of the reducer will also increase significantly, and the transmission efficiency will often decrease. In addition, since the planetary reducer uses spur gear transmission, it is easy to generate vibration and noise during operation, which may affect its performance for precision application scenarios, especially micro equipment.

[0023] Harmonic reducer: Harmonic reducer can provide very high reduction ratio and is suitable for high-precision transmission scenarios, such as industrial robots and precision machinery. The main components of the harmonic reducer include the drive shaft, harmonic generator, flexible wheel and output shaft. When the drive shaft starts to rotate, the inner ring gear fixed to the drive shaft by the harmonic generator also starts to rotate. The cam on the inner ring gear and the groove on the flexible wheel engage with each other, causing the flexible wheel to start rotating. Since the number of grooves on the flexible wheel is usually greater than the number of cams on the inner ring gear, the rotation speed of the flexible wheel is slower than that of the inner ring gear, thereby achieving a deceleration effect. However, the flexible wheel of the harmonic reducer is relatively fragile and cannot withstand large loads, which limits its use in applications such as heavy loads and micro robots. Especially in micro robots, the stability and load-bearing capacity of the harmonic reducer are insufficient, resulting in the inability to meet the needs of long-term high loads and high stability.

[0024] RV reducer: RV reducer adopts cycloid pinwheel transmission, which has smaller size and greater load capacity than traditional planetary gear system. However, RV reducer has complex structure, high manufacturing cost and relatively large size, so its application is limited in space-constrained and cost-sensitive applications, especially in micro-robots or precision surgical robots.

[0025] In view of the limitations of the prior art, the present invention proposes a new type of reducer, which aims to solve the contradiction between high reduction ratio, low weight and small volume of the existing reducer. Through innovative design, the present invention can achieve a large transmission ratio in a small space while maintaining the lightness and efficiency of the reducer. Compared with the prior art, the reducer of the present invention not only has a higher reduction ratio and a smaller volume, but also can reduce the structural weight while outputting high torque, and is suitable for various application scenarios requiring precise control and high load.

[0026] To make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. However, it will be appreciated by those skilled in the art that in the embodiments of the present invention, many technical details are proposed in order to enable the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical scheme claimed in the present application can be implemented. The division of the following embodiments is for the convenience of description, and should not constitute any limitation on the specific implementation of the present invention. The various embodiments can be combined and referenced with each other without contradiction.

[0027] One embodiment of the present invention relates to a reducer based on a double planetary gear, which can be applied to various precision robots, industrial automation equipment, medical equipment, service robots, aerospace systems and other fields. In particular, in robot end effectors such as micro robots and dexterous hands, it can provide high-precision gripping force and high torque output, while being compact and lightweight, and is suitable for scenarios with strict requirements on volume and weight. In addition, the reducer can also be widely used in other equipment that requires efficient transmission and precise control, such as power tools, automated transmission equipment, and precision instruments, to ensure high performance and stability in a variety of working environments.

[0028] An embodiment of the present application includes a sun gear for transmitting external torque to the inside of the reducer; at least one double planetary gear, including a first planetary gear and a second planetary gear, wherein the first planetary gear is meshed with the sun gear, and the number of teeth of the first planetary gear is greater than that of the second planetary gear; a planet carrier, for fixing the double planetary gear on the orbital trajectory, including a first mounting surface and a second mounting surface, the first mounting surface is used to assemble the first planetary gear, and the second mounting surface is used to install the second planetary gear; a first internal gear, meshed with the first planetary gear; a second internal gear, meshed with the second planetary gear, and realizing turnover with the housing through a roller transmission structure, for outputting the torque of the second planetary gear, and the number of teeth of the first internal gear is greater than that of the second internal gear. In the embodiment of the present invention, the differential design of the number of teeth of the double planetary gear and the internal gear is adopted to achieve a graded reduction effect, and effectively convert the high-speed and low-torque output of the motor into low-speed and high-torque. In addition, the integrated single planet carrier fixing method enables the double planetary gear to realize self-rotation and revolution in an integrated structure, simplifies the number of components and gap configuration, and thus effectively compresses the internal space. Finally, a roller transmission structure is provided between the second internal gear and the outer shell to replace the traditional bearing. By eliminating the inner and outer ring components, the size and weight of the overall structure are further reduced while ensuring stable torque output.

[0029] The following is a specific description of the device details of a reducer based on a double planetary gear in an embodiment of the present invention. The following content is only the implementation details provided for easy understanding and is not necessary for the implementation of this solution.

[0030] Figures 1 to 4 The overall structural diagram of the reducer provided in the embodiment of the present application is as follows. The reducer based on the double planetary gear involved in the present application includes:

[0031] Input shaft 1 and output shaft 8: The input shaft 1 is fixedly connected to the sun gear 2 and the external power device, and is used to receive the torque of the external device and rotate the sun gear 2; the output shaft 8 is fixedly connected to the second internal gear 6, and is used to output the torque of the second internal gear 6 outward to form a gripping force.

[0032] Specifically, the input shaft 1 receives torque from an external power device (such as a motor) through a fixed connection with the sun gear 2, and transmits it to the sun gear 2 to rotate the sun gear. This connection method ensures that the torque can be effectively transmitted from the outside to the inside of the reducer. The output shaft 8 is fixedly connected to the second internal gear 6. After receiving the decelerated torque from the second planetary gear 5, the second internal gear 6 transmits the torque to the output shaft through meshing to complete the final power output.

[0033] The sun gear 2 is used to transmit the external torque to the interior of the reducer.

[0034] Specifically, Figure 2 and Figure 3 As shown, the sun gear 2 starts the rotation of the planetary gear system by meshing with the planetary gears. The rotation of the sun gear 2 drives the planetary gears to produce a compound motion, including rotation and revolution. This precise meshing relationship ensures the effective transmission of power.

[0035] At least one double planetary gear comprises a first planetary gear 4 and a second planetary gear 5 , wherein the first planetary gear 4 is meshed with the sun gear 2 , and the number of teeth of the first planetary gear 4 is greater than that of the second planetary gear 5 .

[0036] Optionally, in the reducer, the number of teeth of the first planetary gear 4 is 1 or 2 more than the number of teeth of the second planetary gear 5 , and the number of teeth of the first internal gear 3 is 1 or 2 more than the number of teeth of the second internal gear 6 .

[0037] Specifically, the sun gear 2 receives power from the input shaft 1 and transmits the power to at least one double planetary gear (including the first planetary gear 4 and the second planetary gear 5). The sun gear 2 meshes with the planetary gears to start the planetary gear system to rotate. Due to the precise meshing relationship between the sun gear and the planetary gears, the rotation of the sun gear drives the planetary gears to generate a compound motion of rotation and revolution.

[0038] In addition, if Figure 2 and Figure 3As shown, a double planetary gear system is used inside the reducer. The double planetary gear achieves the function of increasing torque through multi-stage reduction. Specifically, the first planetary gear 4 and the second planetary gear 5 in the double planetary gear are fixedly connected, so their rotation angular velocity is consistent. However, the first planetary gear 4 has a large number of teeth, so when it rotates one circle, its rotation circumference will be greater than the second planetary gear 5. Due to this difference in the number of teeth, the rotation speed of the second planetary gear 5 slows down, and the output torque increases, thereby achieving the effect of a high reduction ratio. Through this design, the reducer is able to increase torque while reducing speed, ensuring high torque and low speed output, and achieving precise power conversion.

[0039] The planet carrier 7 is used to fix the double planetary gear on the orbital track, and includes a first mounting surface and a second mounting surface. The first mounting surface is used to assemble the first planetary gear 4, and the second mounting surface is used to install the second planetary gear 5.

[0040] Optionally, the first planetary gear 4 and the second planetary gear 5 can be limited on the planet carrier 7 by a central shaft or welding.

[0041] Specifically, Figure 1 and Figure 2 As shown, in order to ensure the stability of the double planetary gears during revolution, a planet carrier 7 is designed. The main function of the planet carrier 7 is to keep the double planetary gears on their orbital trajectory and ensure that they move along the predetermined trajectory. The planet carrier 7 can be in the form of a disc or a bracket. The following is an explanation using the disc form as an example: In the disc-shaped planetary carrier 7, there are several limiting holes. By inserting the central axis protrusion of the first planetary gear 4 into a limiting hole on the planet carrier 7, and embedding the middle groove of the second planetary gear 5 into the central axis protrusion of the first planetary gear 4, the limiting of the double planetary gear can be achieved. This design enables the double planetary gear to revolve on a fixed trajectory on the planet carrier 7, ensuring that it remains stable during rotation. In addition, the central axis of the second planetary gear 5 can also be designed as a protrusion, so that the first planetary gear 4 will have a central axis groove. Through this structure, the double planetary gear can also achieve stable limiting and maintain its motion trajectory.

[0042] In addition to using the limiting hole method, the double planetary gear can also be fixed to the planet carrier by welding. This design ensures that the orbital revolution of the double planetary gear can be realized, and also ensures the stability of the structure. After welding, the central axis of the first planetary gear 4 and the second planetary gear 5 will completely overlap, thereby further enhancing the stability and durability of the double planetary gear.

[0043] Optionally, the planet carrier is fixed in the following manner: one end of the center shaft of the planet carrier 7 is connected to the center shaft groove of the sun gear 2 via an optical axis oil film, and the other end of the center shaft is connected to the center shaft groove of the second internal gear 6 via an optical axis oil film.

[0044] Specifically, Figure 1 As shown, in order to ensure that the planet carrier 7 is stably fixed in the reducer and can achieve smooth circulation with the revolution of the double planetary gears, the center axis of the planet carrier 7 is designed with two-end connection. Specifically, one end of the center axis of the planet carrier 7 is connected to the center axis groove of the sun gear 2 through the optical axis oil film, and the other end is connected to the center axis groove of the second internal gear 6 through the oil film. The use of oil film can effectively reduce friction, so that the planet carrier and gears move more smoothly during operation, thereby extending the service life of the reducer. Compared with the structure in traditional technology that realizes the turnover of the planet carrier through the inner and outer rings of the bearing, this design significantly reduces the volume and weight of the reducer through the optical axis oil film connection. Through this innovative structure, the reducer can achieve a more compact and lightweight design while maintaining efficient operation, which is suitable for application scenarios with strict requirements on volume and weight.

[0045] A first internal gear 3 meshing with the first planetary gear 4;

[0046] The second internal gear 6 meshes with the second planetary gear 5 and realizes rotation with the housing 10 via a roller transmission structure, and is used for outputting the torque of the second planetary gear 5 , and the first internal gear 3 has more teeth than the second internal gear 6 .

[0047] Specifically, Figure 1 and Figure 2 As shown, the second planetary gear 5 is meshed with the second internal gear 6, and the movement of the second planetary gear is transmitted to the second internal gear 6 through this meshing. Then, the second internal gear 6 outputs the transmitted torque through the output shaft 8 fixedly connected thereto, completing the transmission of power and the output of torque.

[0048] Optionally, in one embodiment, the roller transmission structure includes: a roller cage installed on the outside of the second internal gear for positioning the roller; and a roller 9 installed on the roller cage in direct contact with the housing of the reducer.

[0049] Specifically, Figure 4As shown, in order to save structural space to the maximum extent, the traditional bearing system is not used between the outer side of the second inner gear 6 and the reducer housing 10. Instead, an outer roller cage is designed on the outer side of the second inner gear, and the balls are evenly arranged on the outer side of the cage. The outer side of the balls is in direct contact with the reducer housing 10, achieving smooth transmission of torque. This solution abandons the design of the inner and outer rings of the traditional bearings, and instead embeds the balls and ball holders between the outer side of the second inner gear and the housing. This design ensures that the outer diameter of the reducer is significantly reduced by precisely controlling the size and form and position tolerances. In addition, the use of an external roller structure enables the reducer to maintain a high torque output capacity and stability while achieving miniaturization and lightweight, thereby improving the overall performance and applicability of the reducer.

[0050] Optionally, the number of double planetary gears that can be installed in the reducer ranges from 2 to 4.

[0051] Specifically, in this embodiment, the number of the double planetary gears in the reducer can be selected between 2 and 4, and the number of the planetary gears is closely related to the structural stability of the reducer. Figure 3 As shown, if two planetary gears are installed in the reducer, the two planetary gears are usually installed in a symmetrical distribution manner to ensure the balance of the reducer's operation and the uniformity of torque transmission. The design of two planetary gears is suitable for applications with low requirements for torque and reduction ratio. At the same time, due to the small number of planetary gears, the structure is simpler and the size of the reducer is more compact. When three or four planetary gears are installed in the reducer, each planetary gear can still maintain a high transmission efficiency and provide more torque transmission paths. The advantage of this design is that it increases the carrying capacity of the planetary gear system, allowing each gear to better share the load and reduce the working pressure of a single gear, thereby improving the durability and reliability of the reducer. In addition, in this embodiment, the number of planetary gears can also be increased to more than four. Increasing the number of planetary gears can further enhance the load distribution capacity, improve structural stability, and increase the durability of the system. However, increasing the number of planetary gears will also increase the volume and weight of the reducer accordingly. Therefore, in miniaturized applications, it is necessary to find a suitable balance between reducing size and enhancing performance.

[0052] Optionally, the thickness of the first planetary gear 4 and the second planetary gear 5 does not exceed 1.2 mm, and the thickness of the planetary carrier does not exceed 1.2 mm. This design makes the total thickness of the combined device of the double planetary gear and the planetary carrier not exceed 3.6 mm, thereby effectively optimizing the internal structure of the reducer. Through this compact design, the reducer can be more compactly integrated into micro devices, and is particularly suitable for use in scenarios with very strict requirements on volume and weight, such as micro robots, dexterous hands and other precision instruments.

[0053] like Figures 1 to 4 As shown, a reducer structure provided in an embodiment of the present application can achieve a reduction ratio of more than 300:1, as shown in the following formula:

[0054]

[0055] Among them, Zi is the tooth value of the corresponding gear, and the subscript i refers to Figures 1 to 4 In this embodiment, the number of teeth of Z2 (sun gear) is 10, the number of teeth of Z3 (first internal gear) and Z6 (second internal gear) are 66 and 65 respectively, and the number of teeth of Z4 (first planetary gear) and Z5 (second planetary gear) are 28 and 27 respectively.

[0056] In general, this embodiment has the following beneficial effects:

[0057] 1. Small size: By adopting a single planetary carrier design and combining the smooth axis oil film technology used in the planetary carrier's circulation, the combined thickness of the double planetary gear and the planetary carrier does not exceed 3.6mm, which greatly reduces the structural volume required to achieve revolution. In addition, the outer roller transmission structure in the design is located outside the second internal gear, further optimizing the space occupation of the reducer and making the entire reducer more compact.

[0058] 2. Low weight: By adopting a single planet carrier design and removing the traditional bearing structure, this embodiment significantly reduces the weight of the reducer compared to the design of multiple planet carriers, bearings and bearing frames in the traditional structure. This lightweight design helps to improve the adaptability of the reducer, especially for miniaturized equipment and applications with strict weight requirements.

[0059] 3. High torque output: Through the design of double planetary gears and the difference in the number of teeth between the first planetary gear, the second planetary gear, the first internal gear and the second internal gear, the reducer achieves a multi-stage reduction effect. This design effectively increases the external input torque, and in a specific embodiment, the reduction ratio reaches more than 300:1, thereby providing a higher output torque to meet the needs of high-load applications.

[0060] In the embodiment of the present invention, the differential design of the number of teeth of the double planetary gear and the internal gear is adopted to achieve a graded deceleration effect, effectively converting the high-speed and low-torque output of the motor into low-speed and high-torque. In addition, the integrated single planetary carrier fixing method enables the double planetary gear to realize rotation and revolution in an integrated structure, simplifying the number of parts and gap configuration, thereby effectively compressing the internal space. Finally, a roller transmission structure is set between the second internal gear and the outer shell to replace the traditional bearing. By eliminating the inner and outer ring components, the size and weight of the overall structure are further reduced while ensuring the stability of the torque output.

[0061] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0062] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists, A and B exist at the same time, and B exists. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0063] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0064] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0065] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like 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 a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0066] Another embodiment of the present invention relates to a driving device, such as Figures 5 to 7 As shown, it includes a reducer based on a double planetary gear, and a drive motor;

[0067] The driving motor is used to input a rotational torque to the reducer;

[0068] The reducer is used to receive the torque input from the driving motor and output the torque to the outside after reducing the input torque inside the reducer.

[0069] Specifically, in Figure 5 In the embodiment, the structure of the driving device is composed of multiple key components, including a driving motor 11 and a reducer. First, the driving motor 11 is used as a power source to provide driving force, and the driving motor 11 is fixedly connected to the reducer through a connecting flange 12. Through the connecting flange 12, the driving motor 11 transmits power to the transmission system inside the reducer.

[0070] like Figure 6 As shown, the first internal gear 3 is meshed with the first planetary gear 4, and the first planetary gear 4 receives the power from the drive motor 11 and transmits the power to the next level of the transmission system through the second planetary gear 5 fixedly connected thereto. In particular, the first planetary gear 4 and the second planetary gear 5 are double gears, which means that they rotate synchronously while rotating on their own, thereby improving the efficiency of power transmission. The second planetary gear 5 is meshed with the second internal gear 6, and through this cooperation, torque is transmitted and speed reduction is achieved.

[0071] In addition, if Figure 7 As shown, the rollers 9 play a vital role in the reducer, and they are used to keep the second internal gear 6 stably rotating around the reducer housing 13. With the assistance of the rollers 9, the second internal gear 6 can rotate smoothly in the reducer, and finally drive the output synchronous wheel 14 to rotate. The output synchronous wheel 14 is connected to the output shaft, and then outputs the decelerated low-speed, high-torque power to the external load system, realizing the required driving function.

[0072] This application Figures 5 to 7 The drive device structure provided in the embodiment can achieve a reduction ratio exceeding 400:1, as shown in the following formula:

[0073]

[0074] Among them, Zi represents the number of teeth of the corresponding gear, and the subscript i represents Figures 1 to 4 The numbers of the various components of the reducer. Specifically, the number of teeth of Z2 (sun gear) is 10, the number of teeth of Z3 (first internal gear) and Z6 (second internal gear) are both 73, the number of teeth of Z4 (first planetary gear) is 32, and the number of teeth of Z5 (second planetary gear) is 41. Through such a gear design, the reducer can achieve a reduction ratio of up to 467.2, ensuring high torque output while reducing speed, and is suitable for application scenarios that require large torque and precise control.

[0075] The drive device combined with the motor provides low-speed and high-torque output through efficient power transmission and torque amplification. The high speed and low torque of the motor is reduced and increased through the double planetary gear system in the reducer to ensure stable power output. This design is suitable for applications with limited space and high load and precision requirements, such as micro robots and precision machinery.

[0076] Another embodiment of the present invention relates to a dexterous hand, comprising a driving device as described in the above embodiment, capable of realizing joint operation based on the torque output by the driving device.

[0077] Those skilled in the art will appreciate that the above embodiments are specific embodiments for implementing the present invention, and that in actual applications, various changes may be made in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A reducer based on a double planetary gear, characterized in that: include: A sun gear, used for transmitting external torque to the interior of the reducer; at least one double planetary gear, comprising a first planetary gear and a second planetary gear, wherein the first planetary gear is meshed with the sun gear, and the first planetary gear has more teeth than the second planetary gear; A planet carrier, used to fix the double planetary gear on the orbital track, comprising a first mounting surface and a second mounting surface, wherein the first mounting surface is used to assemble the first planetary gear, and the second mounting surface is used to install the second planetary gear; a first internal gear meshing with the first planetary gear; The second internal gear is meshed with the second planetary gear and realizes rotation with the outer shell through a roller transmission structure, and is used for outputting the torque of the second planetary gear. The number of teeth of the first internal gear is greater than that of the second internal gear.

2. The double planetary gear reducer according to claim 1, characterized in that: Also includes an input shaft and an output shaft, wherein, The input shaft is fixedly connected to the sun gear and the external power device, and is used to receive the torque of the external device and rotate the sun gear; The output shaft is fixedly connected to the second internal gear and is used to output the torque of the second internal gear outward to form a gripping force.

3. The double planetary gear reducer according to claim 1, characterized in that: The first planetary gear and the second planetary gear are limited on the planetary carrier by a central shaft or welding.

4. The double planetary gear reducer according to claim 1, characterized in that: One end of the center shaft of the planet carrier is connected to the center shaft groove of the sun gear through an optical axis oil film, and the other end is connected to the center shaft groove of the second internal gear through an optical axis oil film.

5. The double planetary gear reducer according to claim 1, characterized in that: The thickness of the first planetary gear and the second planetary gear does not exceed 1.2 mm, and the thickness of the planet carrier does not exceed 1.2 mm.

6. The double planetary gear reducer according to claim 1, characterized in that: The number of the double planetary gears ranges from 2 to 4.

7. The double planetary gear reducer according to claim 1, characterized in that: The number of teeth of the first planetary gear is 1 or 2 more than the number of teeth of the second planetary gear, and the number of teeth of the first internal gear is 1 or 2 more than the number of teeth of the second internal gear.

8. The double planetary gear reducer according to claim 1, characterized in that: The roller transmission structure comprises: A roller cage, mounted on the outer side of the second internal gear, for positioning the rollers; The rollers are mounted on the roller retaining frame and are in direct contact with the housing of the reducer.

9. A driving device, characterized in that: A reducer based on a double planetary gear as claimed in any one of claims 1 to 8, and a drive motor; The driving motor is used to input a rotational torque to the reducer; The reducer is used to receive the torque input from the driving motor and output the torque to the outside after reducing the input torque inside the reducer.

10. A dexterous hand, characterized in that: The invention comprises the driving device of claim 9, wherein the joint operation is realized based on the torque output by the driving device.

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