Small RV speed reducer for humanoid robot joints

Abstract

The invention discloses a small RV speed reducer for humanoid robot joints. The small RV speed reducer comprises an input assembly, a speed reduction assembly and an output flange. The input assembly drives the transmission sun gear through the input shaft and is meshed with the crank planetary gear set to form first-stage speed reduction. The crank planetary gear set drives the small-tooth-difference gear pair assembly (including the upper / lower winding wheel and the pin wheel housing) to perform planetary motion with a certain angle phase difference, and second-stage speed reduction is achieved. And the output flange is in threaded connection with the input end cover to finish power output. Through compact integration of the planetary gear and the cycloidal gear mechanism, the outer diameter of the speed reducer is controlled within 80 mm, the thickness of the speed reducer is smaller than 30 mm, the high reduction ratio is guaranteed, meanwhile, the size and weight are remarkably reduced, the transmission efficiency is greatly improved, and the speed reducer is suitable for humanoid robot joint scenes with limited space.

Description

Technical Field

[0001] The present invention relates to the technical field of reducers, and in particular to a small RV reducer. Background Art

[0002] As the key component for the robot to achieve flexible movement, the performance of the humanoid robot joint directly affects the overall working efficiency of the robot. The reducer plays a vital role in the robot joint. It can reduce the motor speed and increase the torque, so that the robot joint can move accurately and stably. With the development of reducer technology towards miniaturization, lightweight and integration, more stringent requirements are put forward for the size of reducers for humanoid robot joints. Due to the limitations of its structural design and manufacturing process, the overall size of the traditional RV reducer is large, which is difficult to meet the needs of small humanoid robot joints and some application scenarios with strict space requirements. In addition, most of its components are made of ordinary steel and other materials, and the overall weight is large, which will increase the load of the robot, increase the energy consumption of the robot, and reduce the working efficiency and endurance. At the same time, during the transmission process of the traditional RV reducer, due to the meshing mode of the pin wheel and the cycloid wheel and the friction between the gears and other factors, there is a certain amount of energy loss, resulting in insufficient transmission efficiency. The low transmission efficiency will not only increase the energy consumption of the robot, but also cause the reducer to generate more heat during the operation process, affecting the stability and service life of the reducer. In summary, the existing RV reducers are rarely used in the field of humanoid robots and have many shortcomings in terms of size, weight and transmission efficiency. It is urgent to develop a new type of small RV reducer to meet the needs of the development of modern humanoid robot technology. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0004] To this end, the purpose of the present invention is to propose a small RV reducer for humanoid robot joints, which is highly optimized in structural design and integrates the planetary gear mechanism and the cycloid gear mechanism into a compact housing, thereby achieving a significant reduction in size and weight, meeting the needs of miniaturization and lightweight of robots.

[0005] To achieve the above-mentioned purpose, the present invention proposes a small RV reducer for humanoid robot joints, characterized in that the reducer includes an input component, a reduction component and an output flange, wherein the input component mainly includes an input shaft and an input end cover, wherein a transmission sun gear is installed at the output end of the input shaft, and the transmission sun gear coincides with the central axis of the input shaft; the reduction component is fixedly connected to the input component and the output component, and the reduction component includes a crank planetary gear set and a small-tooth difference gear pair assembly, wherein the crank planetary gear set and the transmission sun gear on the input shaft are meshed with each other to form a transmission; each crank planetary gear set is provided with a section of crankshaft, and the small-tooth difference gear pair assembly is installed on the crankshaft, and the crank planetary gear set is meshed with the transmission sun gear for transmission, so that the small-tooth difference gear pair assembly synchronously generates planetary rotation; the output flange is mainly used for speed reduction output, and the output flange is connected to the input end cover by a thread.

[0006] In addition, the small RV reducer for humanoid robot joints proposed in the application may also have the following additional technical features:

[0007] Specifically, the small-tooth-difference gear pair assembly includes an upper cycloidal wheel, a lower cycloidal wheel and a pinion housing, the centers of the upper cycloidal wheel and the lower cycloidal wheel are provided with holes of the same size, an inner gear ring is provided inside the pinion housing, the upper cycloidal wheel and the lower cycloidal wheel are arranged in opposite directions with conjugate tooth profiles, and perform planetary motion around an eccentric trajectory with a certain angular phase difference.

[0008] Specifically, the upper cycloid wheel and the lower cycloid wheel are both provided with the same number of teeth and the difference in the number of teeth between the upper cycloid wheel and the inner gear ring of the pin gear housing is 1 tooth.

[0009] Specifically, the crank gear set includes three identical gear shafts, and the crank shaft arranged on the gear shaft is an eccentric shaft.

[0010] Specifically, the meshing clearance between the upper cycloid wheel, the lower cycloid wheel and the pin gear housing is adjusted by the crank gear set.

[0011] Specifically, a center hole is provided on one end face of the input shaft, a threaded hole is provided on a vertical face of the center hole, the center hole is used to connect the output shaft of the motor, and the threaded hole fixes the input shaft and the motor output shaft together through a set screw.

[0012] Specifically, the upper cycloid wheel and the lower cycloid wheel are provided with three equally-sized equally-divided holes around their respective center holes, and the crank gear set sequentially passes through the equally-divided holes to achieve transmission connection with the upper cycloid wheel and the lower cycloid wheel.

[0013] Specifically, the crankshaft is provided with a total of 5 shaft sections, and the first shaft section and the fifth shaft section are installed with matching first bearings, which are respectively used to connect the output flange and the input end cover, and the second shaft section and the fourth shaft section are installed with matching second bearings, which are respectively used to connect the lower cycloid wheel and the upper cycloid wheel.

[0014] Specifically, the third shaft section of the crankshaft is arranged so that a lubrication channel is formed inside the reducer to provide lubrication to the small-tooth-difference gear pair assembly.

[0015] Specifically, the overall outer diameter of the reducer is less than 80 mm, and the overall thickness of the reducer is less than 30 mm.

[0016] By means of the above technical solution, the small RV reducer for robot joints of the present invention has at least the following beneficial effects:

[0017] 1. This application significantly reduces the overall volume of the RV reducer by simplifying components and compacting the layout design, making it more suitable for robot joint scenarios with limited space.

[0018] 2. The RV reducer of the present application realizes power input through the coaxial connection between the input shaft and the motor output shaft. The input shaft drives the transmission sun gear fixed at its end to rotate, and then transmits power through the meshing of the sun gear and three circumferentially evenly distributed planetary gears. Each planetary gear is rigidly connected to the upper cycloid gear and the lower cycloid gear through the crankshaft and the bearing assembly, forcing the upper and lower cycloid gears to move around the inner gear ring under phase synchronization conditions, forming a two-stage planetary reduction mechanism. At the same time, the input end cover, the upper cycloid wheel, the lower cycloid wheel and the output flange are fixed by an axial locking structure, and finally the decelerated power is transmitted to the output end. This structure significantly improves the transmission stability, while further reducing the axial length required for the traditional reducer, which greatly reduces the product size. This optimization can not only greatly improve production efficiency and reduce assembly difficulty, but also effectively reduce production costs and effectively enhance the practicality of the product.

[0019] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0021] Figure 1 An exploded disassembly diagram of a small RV reducer for a humanoid robot joint provided by the present invention;

[0022] Figure 2An exploded disassembly diagram from another perspective of a small RV reducer for a humanoid robot joint provided by the present invention;

[0023] Figure 3 A schematic diagram of the gear shaft structure of a small RV reducer for a humanoid robot joint provided by the present invention;

[0024] Figure 4 A schematic diagram of the input shaft structure of a small RV reducer for a humanoid robot joint provided by the present invention;

[0025] Figure 5 This is a schematic diagram of the overall structure of a small RV reducer for a humanoid robot joint provided by the present invention;

[0026] Figure 6 A schematic diagram of the structure of a small-tooth-difference gear pair assembly of a small RV reducer for a humanoid robot joint provided by the present invention;

[0027] Figure 7 A schematic diagram of the cross-sectional structure of a pin gear housing of a small RV reducer for a humanoid robot joint provided by the present invention;

[0028] Figure 8 A schematic diagram of the structure of an input end cover of a small RV reducer for a humanoid robot joint provided by the present invention;

[0029] Fig. 9 This is a schematic structural diagram of an output flange of a small RV reducer for a humanoid robot joint provided by the present invention.

[0030] Figure numerals: 1. input shaft; 2. retaining rack; 3. input end cover; 4. pinion housing; 5. upper cycloid wheel; 6. lower cycloid wheel; 7. first bearing; 8. second bearing; 9. crank planetary gear set; 10. input shaft support bearing; 11. output flange; 12. ball; 13. sealing ring; 14. screw; 18. transmission sun gear; 19. small-tooth difference gear subassembly; 31. main bearing inner ring; 41. main bearing outer ring; 91. first shaft section; 92. second shaft section; 93. third shaft section; 94. fourth shaft section; 95. fifth shaft section; 111. main bearing inner ring. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0033] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0034] The following is combined with Figure 1-9 The present invention is described in further detail.

[0035] One embodiment of the present invention proposes a small RV reducer for a humanoid robot joint, which includes an input component, a reduction component and an output component, wherein the input component mainly includes an input shaft 1 and an input end cover 3, wherein a transmission sun gear 18 is installed at the output end of the input shaft 1, and the transmission sun gear 18 coincides with the central axis of the input shaft 1; the reduction component is fixedly connected to the input component and the output component, and the reduction component includes a crank planetary gear set 9 and a small-tooth difference gear subassembly 19, wherein the crank planetary gear set 9 and the transmission sun gear 18 on the input shaft 1 are meshed with each other to form a transmission; a crankshaft is provided on each crank planetary gear set 9, and the small-tooth difference gear subassembly 19 is installed on the crankshaft, and the crank planetary gear set 9 is meshed with the transmission sun gear 18 for transmission, so that the small-tooth difference gear subassembly 19 synchronously generates planetary rotation; the output flange 11 is mainly used for reduction output, and the output flange 11 is connected to the input end cover 3 by a thread.

[0036] like Figure 1-2 As shown, it should be explained that the small-tooth difference gear pair assembly 19 includes an upper cycloidal wheel 5, a lower cycloidal wheel 6 and a pinion housing 4. The upper cycloidal wheel 5 and the lower cycloidal wheel 6 are provided with center holes of the same size in the centers. In addition, a center hole is also provided in the input end cover 3. The input shaft 1 passes through the input end cover 3, the upper cycloidal wheel 5 and the lower cycloidal wheel 6 in sequence, so that the transmission sun gear 18 installed on the input shaft 1 is meshed with the crank planetary gear set 9, thereby performing planetary transmission.

[0037] like Figure 6As shown, the small-tooth-difference gear pair assembly 19 also includes a pinion housing 4, inside which an inner gear ring is arranged, and the difference in the number of teeth between the upper cycloid wheel 5 and the lower cycloid wheel 6 and the inner gear ring is 1 tooth, which greatly improves the compactness of the structure and the stability of movement.

[0038] like Figure 1-3 As shown, the crank planetary gear set 9 includes three identical gear shafts, the crank shaft arranged on the gear shaft is a double eccentric shaft, the upper cycloid gear 5 and the lower cycloid gear 6 are diagonally installed on the eccentric shaft, and when the transmission sun gear 18 drives the crank planetary gear set 9 to engage and rotate, the upper cycloid wheel 5 and the lower cycloid wheel 6 installed on the eccentric shaft rotate along the curve, and then engage with the pinion housing, thereby achieving the purpose of deceleration.

[0039] like Figure 4 As shown, the input shaft 1 and the transmission sun gear 18 are arranged as an integrated structure, which greatly avoids the coaxiality deviation caused by the split connection and ensures the stability of movement. A center hole is opened at one end of the input shaft, and a threaded hole is opened in the vertical direction of the center hole. The center hole is used to connect the motor output shaft, and then a set screw is inserted into the vertical threaded hole to fix the input shaft 1 and the motor output shaft together.

[0040] like Figure 1 As shown, a total of 5 shaft sections are arranged on the crank shaft, and the first shaft section 91 and the fifth shaft section 95 are installed with matching first bearings 7, which are respectively used to connect the output flange 11 and the input end cover 3 and provide support for them, and the second shaft section 92 and the fourth shaft section 94 are installed with matching second bearings 8, which are respectively used to connect the lower cycloid wheel 6 and the upper cycloid wheel 5.

[0041] In the above example, the first bearing 7 is provided to provide support for the output flange 11 and the input end cover 3 , thereby improving the rotation stability of the output flange 11 and the input end cover 3 .

[0042] like Figure 1 and Figure 7-9 As shown, the main bearings at the input end and the output end are respectively arranged with their connecting components into an integrated structure, a main bearing inner ring 31 is arranged at the input end cover, a main bearing inner ring 111 is arranged at the output flange, and a main bearing outer ring 41 is arranged at the corresponding position of the pin gear housing 4. During assembly, the inner and outer rings of the main bearing are matched together by balls to form a complete main bearing, which greatly reduces the size of the reducer while ensuring the stability of the reducer performance and makes the reducer structure more compact.

[0043] like Figure 3As shown, by setting the third shaft section 93 on the crankshaft, a hollow lubrication channel is formed between the upper cycloidal wheel 5 and the lower cycloidal wheel 6, and the lubricating oil or grease is injected into the meshing area of ​​the small-tooth difference gear pair assembly 19 through the channel, which greatly reduces the friction and wear during transmission and ensures the high-precision transmission and long-term operation of the reducer.

[0044] like Figure 1 and Figure 5 As shown, a sealing ring 13 is arranged between the output flange 11 and the pin gear housing 4 to prevent the leakage of lubricating grease inside the reducer, block the invasion of external pollutants, and improve the transmission accuracy and stability.

[0045] In summary, it should be noted that the overall outer diameter of a small RV reducer for humanoid robot joints in this application is less than 80 mm, and the overall thickness of the reducer is less than 30 mm. The size of the traditional reducer is greatly reduced, and while miniaturization is ensured, a larger reduction ratio is provided to meet the requirements for reducer performance, which greatly improves production efficiency, reduces assembly difficulty, reduces production costs, and increases practicality.

[0046] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A small RV reducer for humanoid robot joints, characterized in that: The reducer comprises an input component, a reduction component and an output flange, wherein: The input assembly mainly includes an input shaft and an input end cover, wherein: A transmission sun gear is installed at the output end of the input shaft, and the transmission sun gear coincides with the central axis of the input shaft; The reduction assembly is fixedly connected to the input assembly and the output assembly, and the reduction assembly includes a crank planetary gear set and a small tooth difference gear pair assembly, wherein: The crank planetary gear set and the transmission sun gear on the input shaft are meshed with each other to form a transmission; each crank planetary gear set is provided with a section of crankshaft, and the small-tooth-difference gear pair assembly is installed on the crankshaft, and the crank planetary gear set is meshed with the transmission sun gear for transmission, so that the small-tooth-difference gear pair assembly synchronously generates planetary rotation; The output flange is mainly used for reducing the output, and the output flange is connected to the input end cover by threads.

2. A small RV reducer for humanoid robot joints according to claim 1, characterized in that: The small-tooth-difference gear pair assembly includes an upper cycloidal wheel, a lower cycloidal wheel and a pinion housing. The centers of the upper cycloidal wheel and the lower cycloidal wheel are provided with holes of the same size. An inner gear ring is provided inside the pinion housing. The upper cycloidal wheel and the lower cycloidal wheel are arranged in opposite directions with conjugate tooth profiles, and perform planetary motion around an eccentric trajectory with a certain angular phase difference.

3. A small RV reducer for humanoid robot joints according to claim 2, characterized in that: The upper cycloid wheel and the lower cycloid wheel are both provided with the same number of teeth and the difference in the number of teeth between the upper cycloid wheel and the inner gear ring of the pin gear housing is 1 tooth.

4. The small RV reducer for humanoid robot joints according to claim 1, characterized in that: The crank planetary gear set includes three identical gear shafts, and the crank shaft arranged on the gear shaft is an eccentric shaft.

5. The small RV reducer for humanoid robot joints according to claim 1, characterized in that: The meshing clearance between the upper cycloid wheel, the lower cycloid wheel and the pin gear housing is adjusted by the crank gear set.

6. The small RV reducer for humanoid robot joints according to claim 1, characterized in that: A center hole is provided on one end face of the input shaft, a threaded hole is provided on a vertical face of the center hole, the center hole is used to connect the output shaft of the motor, and the threaded hole fixes the input shaft and the output shaft of the motor through a set screw.

7. The small RV reducer for humanoid robot joints according to claim 1, characterized in that: The upper cycloid wheel and the lower cycloid wheel are provided with three equally-sized equally-divided holes around their respective center holes, and the crank gear set passes through the equally-divided holes in sequence to achieve transmission connection with the upper cycloid wheel and the lower cycloid wheel.

8. The small RV reducer for humanoid robot joints according to claim 4, characterized in that: The crankshaft is provided with 5 shaft sections in total, and the first shaft section and the fifth shaft section are installed with matching first bearings, which are respectively used to connect the output flange and the input end cover, and the second shaft section and the fourth shaft section are installed with matching second bearings, which are respectively used to connect the lower cycloid wheel and the upper cycloid wheel.

9. A small RV reducer for humanoid robot joints according to claim 8, characterized in that: The third shaft section of the crankshaft is arranged so that a lubrication channel is formed inside the reducer to provide lubrication to the small-tooth-difference gear pair assembly.

10. A small RV reducer for humanoid robot joints according to claim 1, characterized in that: The overall outer diameter of the reducer is less than 80 mm, and the overall thickness of the reducer is less than 30 mm.

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