A two-stage planetary reduction robot joint module

Abstract

The utility model discloses a two -stage planetary deceleration's robot joint module, including planetary output T type cylinder, precision peg, planetary output bearing end cover, output end front bearing, two -stage gear ring, motor casing, two -stage planetary cage, two -stage sun wheel, needle bearing, planetary wheel gasket, two -stage planetary wheel, connecting flange, torque motor, one -stage gear ring, one -stage front bearing, one -stage planetary cage, planetary wheel gasket, needle, precision needle, one -stage sun wheel, one -stage planetary wheel, one -stage rear bearing, rotor inner cover, rotor inner cover rear bearing, output end rear bearing, code disc, encoder magnet, back end cover, hexagonal copper column, drive board, motor tail cover.

Description

Technical Field

[0001] This utility model belongs to the field of robot joint technology, and more specifically, it relates to a robot joint module with a two-stage planetary deceleration system. Background Technology

[0002] As the core execution unit of a robot's motion system, the performance of the robot's joint module directly affects the robot's motion accuracy, load capacity, and dynamic response characteristics. With the rapid development of humanoid robots, collaborative robots, and precision industrial equipment, more stringent technical requirements have been placed on joint modules: achieving high torque output, high transmission accuracy, low vibration and noise, and excellent power density within a limited space. The reducer, as the core transmission component of the joint module, directly determines the overall performance of the joint module through its selection and design.

[0003] Currently, there are four main technical routes for precision reducers used in robot joints: harmonic reducers, RV reducers, planetary reducers, and cycloidal pinwheel reducers. Planetary reducers, with their advantages of robust structure, controllable cost, and relatively low manufacturing difficulty, are widely used in joints such as robot hands where precision requirements are relatively low. Compared with other reducers, planetary reducers use multi-tooth meshing to distribute load, resulting in higher torque capacity and better shock resistance. However, their main drawback is the limited single-stage transmission ratio (only 3-10), and the transmission accuracy is relatively lower than that of harmonic and cycloidal pinwheel reducers. To overcome the insufficient reduction ratio of single-stage planetary reducers, the traditional solution uses a two-stage standard planetary gear train in series. However, this approach leads to excessively large axial dimensions, increased structural components and connecting parts, which not only increases weight and complexity but also reduces system rigidity and transmission accuracy. Especially with the trend towards miniaturization, planetary gear trains face strict dimensional limitations in both radial and axial directions. The large number of structural components and connecting parts in a two-stage planetary gear train leads to complex joint structures and installation difficulties.

[0004] Currently, planetary reducer joint modules face three major technical bottlenecks:

[0005] The conflict between reduction ratio and size: the reduction ratio of a single-stage planetary reducer is limited, while the axial dimension of a two-stage planetary reducer in series is too large, which cannot meet the high torque density requirements of the lower limb joints of humanoid robots.

[0006] Insufficient control precision: Conventional planetary joint modules only have encoders on the motor end, which cannot directly detect the output state, resulting in low control precision at the joint output end and the inability to achieve zero-position memory function. Adding an additional encoder to the output end would lead to structural complexity and increased size.

[0007] Insufficient integration and heat dissipation: The motors and reducers inside the robot joints generate a lot of heat during operation. Traditional heat dissipation designs are difficult to achieve efficient thermal management in a confined space, resulting in increased joint temperature and reduced lifespan. Utility Model Content

[0008] To address the shortcomings of existing technologies, this invention provides a two-stage planetary deceleration robot joint module to solve the problems mentioned in the background section.

[0009] To achieve the above objectives, this utility model is implemented through the following technical solution: including a planetary output T-shaped cylinder, precision pins, a planetary output bearing end cover, an output end front bearing, a secondary gear ring, a motor housing, a secondary planetary cage, a secondary sun gear, a needle roller bearing, planetary gear washers, a secondary planetary gear, a connecting flange, a torque motor, a primary gear ring, a primary front bearing, a primary planetary cage, a primary sun gear, a primary planetary gear, a primary rear bearing, a rotor inner sleeve, a rotor inner sleeve rear bearing, an output end rear bearing, a code disk, an encoder magnet, a rear end cover, a hexagonal copper column, a drive plate, and a motor tail cover;

[0010] The planetary output bearing end cover is fixedly connected to the secondary gear ring and together they fix the outer ring of the output front bearing. The end of the planetary output T-tube is fixed with an encoder magnet and is fixedly connected to the secondary planetary gear cage. The planetary output T-tube and the secondary planetary gear together fix the inner ring of the output front bearing. The needle roller bearing is installed in the secondary planetary gear and fixed in the secondary planetary cage. The outer ring of the secondary planetary gear meshes with the secondary gear ring, and the inner ring of the secondary planetary gear meshes with the secondary sun gear.

[0011] Preferably, the upper end of the secondary sun gear is fixed to the primary planetary cage and radially locked with screws; the outer side of the primary planetary cage is fitted with the primary gear ring to fix the primary front bearing and the primary rear bearing; the connecting flange is fixedly connected to the primary gear ring; the primary planetary gear is equipped with a needle roller bearing and its inner side meshes with the primary sun gear.

[0012] Preferably, the rear end cover is provided with a motor housing fixedly connected to the outside, and the rear end cover is provided with a drive plate fixed by a hexagonal copper column. The motor tail cover is fixed together with the rear end cover and the motor housing.

[0013] Preferably, the first-stage sun gear is tightly connected to the rotor inner sleeve, and a tightly connected rotor is provided on the outside of the rotor inner sleeve. The rotor inner sleeve and the rear end cover fix the rotor inner sleeve rear bearing, and the rotor inner sleeve and the planetary output T-shaped cylinder fix the output end rear bearing.

[0014] Preferably, the planetary output T-tube is equipped with a number of precision pins.

[0015] Preferably, the surfaces of the first-stage planetary gear and the second-stage planetary gear are provided with planetary gear washers.

[0016] Preferably, a torque motor is also provided between the primary gear ring and the secondary planetary gear.

[0017] Preferably, the encoder magnet surface is provided with a code disk.

[0018] This invention provides a two-stage planetary reducer robot joint module with the following advantages: The module adopts a nested structure, embedding the first-stage planetary gear train inside the shaft to achieve extreme compression of the axial dimension. This nested design provides an 18-to-1 reduction ratio within a 50mm axial dimension, reducing the axial space by more than 30% compared to traditional serial structures. Simultaneously, a magnetic ring and encoder are provided at the output end to achieve closed-loop control. The motor, controller, and two-stage reducer are highly integrated into the joint housing, achieving a unified shaft, disk, and housing, avoiding redundant connecting structures, forming a modular joint unit, and improving torque transmission stability, system reliability, and service life. Attached Figure Description

[0019] Figure 1 This is a cross-sectional view of the overall structure of this utility model.

[0020] Figure 2 This is an exploded view of the overall structure of this utility model.

[0021] Figure 3 This is an exploded view of the lower part of the structure of this utility model.

[0022] Figure 4 This is an exploded view of the upper part of the structure of this utility model.

[0023] In the diagram: 1. Planetary output T-shaped cylinder; 2. Precision pin; 3. Planetary output bearing end cover; 4. Output end front bearing; 5. Secondary gear ring; 6. Motor housing; 7. Secondary planetary cage; 8. Motor tail cover; 9. Secondary sun gear; 10. Needle roller bearing; 11. Planetary gear washer; 12. Secondary planetary gear; 13. Connecting flange; 14. Drive plate; 15. Torque motor; 16. Primary gear ring; 17. Primary front bearing; 18. Primary planetary cage; 19. Encoder disk; 20. Rear end cover; 21. Hexagonal copper column; 22. Primary sun gear; 23. Primary planetary gear; 24. Primary rear bearing; 25. Encoder magnet; 26. Rotor inner sleeve; 27. Output end rear bearing; 28. Rotor inner sleeve rear bearing. Detailed Implementation

[0024] The embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of this utility model.

[0025] In the description of this utility model, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In addition, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0026] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0027] Please see Figures 1 to 4 This utility model provides a technical solution: a two-stage planetary reduction robot joint module, including a planetary output T-shaped cylinder 1, a precision pin 2, a planetary output bearing end cover 3, an output end front bearing 4, a secondary gear ring 5, a motor housing 6, a secondary planetary cage 7, a secondary sun gear 9, a needle roller bearing 10, a planetary gear washer 11, a secondary planetary gear 12, a connecting flange 13, a torque motor 15, a primary gear ring 16, a primary front bearing 17, a primary planetary cage 18, a primary sun gear 22, a primary planetary gear 23, a primary rear bearing 24, a rotor inner sleeve 26, an output end rear bearing 27, an encoder disk 19, an encoder magnet 25, a rear end cover 20, a hexagonal copper column 21, a drive plate 14, and a motor tail cover 8;

[0028] The planetary output bearing end cover 3 is fixedly connected to the secondary gear ring 5, together fixing the outer ring of the output end front bearing 4.

[0029] An encoder magnet 25 is fixed at the end of the planetary output T-shaped cylinder 1 and is fixedly connected to the cage of the secondary planetary gear 12, together fixing the inner ring of the output end front bearing 4. The needle roller bearing 10 is installed in the four secondary planetary cages 7 and fixed together in the secondary planetary cages 7. The outer ring of the planetary gear meshes with the secondary gear ring 5, and the inner ring meshes with the secondary sun gear 9.

[0030] The upper end of the second-stage sun gear 9 is fixed to the first-stage planetary gear 23 and radially locked with screws. The outer side of the first-stage planetary gear 23 is fitted with the first-stage gear ring 16 to fix the front and rear bearings. At the same time, the connecting flange 13 is fixedly connected to the first-stage gear ring 16.

[0031] The first-stage planetary gear 23 is similar to the second-stage planetary gear 12 and is equipped with a needle roller bearing 10, which meshes with the sun gear on the inner side.

[0032] The first-stage sun gear 22 is tightly connected to the rotor inner sleeve 26. The outer side of the rotor inner sleeve 26 is tightly connected to the rotor and the rear bearing of the rotor inner sleeve 26 is fixed with the rear end cover 20. The rear bearing 27 of the output end is fixed with the planetary output T-type cylinder 1.

[0033] The stator is tightly connected to the outer casing, the rear end cover 20 is connected and fixed to the motor casing 6, the drive plate 14 is positioned and fixed on the rear end cover 20 by the hexagonal copper column 21, and the motor tail cover 8 is fixed together with the rear end cover 20 and the motor casing 6.

[0034] To achieve lightweighting of the joint module, this solution incorporates some optimizations, including weight-reduction holes and grooves for the housing and planetary output T-shaped cylinder 1.

[0035] When the motor is enabled, the frameless motor is controlled by the driver and rotates according to the command. The rotor bushing drives the first-stage sun gear 22 to rotate, which in turn drives the four first-stage planetary gears to rotate, meshing with the fixed external gear ring. Simultaneously, it drives the first-stage planetary carrier to rotate. The speed of the planetary carrier is much lower than that of the sun gear, achieving first-stage speed reduction. Similarly, the first-stage planetary carrier 18 drives the second-stage sun gear 9 to rotate. In the same way, the second-stage planetary carrier, as the final output, is fixedly connected to the planetary output T-shaped cylinder 1 to transmit power, thereby reducing speed and increasing torque.

[0036] Based on the robot joint module obtained above, the parameters are as follows:

[0037] 69rpm 111rpm 145Nm 324Nm

[0038] When the above scheme is adopted, a transmission ratio of 18 can be achieved, and the peak output torque can reach 324 Nm.

[0039] By using dual encoder signal detection, the input and output speeds can be detected separately, thereby improving control accuracy. Continuous deceleration is achieved through primary and secondary reducers, increasing the transmission ratio of the planetary reducer and resulting in greater torque output.

[0040] The planetary reduction joint module in this solution highly integrates components such as motors, reducers, controllers, and encoders, successfully achieving miniaturization and lightweighting of high-torque output joint modules, thus facilitating the rapid assembly and deployment of robots.

[0041] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A robot joint module with a two-stage planetary deceleration system, characterized in that: Includes planetary output T-shaped cylinder (1), precision pin (2), planetary output bearing end cover (3), output end front bearing (4), secondary gear ring (5), motor housing (6), secondary planetary cage (7), secondary sun gear (9), needle roller bearing (10), planetary gear gasket (11), secondary planetary gear (12), connecting flange (13), torque motor (15), primary gear ring (16), primary front bearing (17), primary planetary cage (18), primary sun gear (22), primary planetary gear (23), primary rear bearing (24), rotor inner sleeve (26), rotor inner sleeve rear bearing (28), output end rear bearing (27), code disk (19), encoder magnet (25), rear end cover (20), hexagonal copper column (21), drive plate (14), motor tail cover (8); The planetary output bearing end cap (3) is fixedly connected to the secondary gear ring (5) and together they fix the outer ring of the output front bearing (4). The end of the planetary output T-shaped cylinder (1) is fixed with an encoder magnet (25) and is fixedly connected to the cage of the secondary planetary gear (12). The planetary output T-shaped cylinder (1) and the secondary planetary gear (12) together fix the inner ring of the output front bearing (4). The needle roller bearing (10) is installed in the secondary planetary gear (12) and fixed in the secondary planetary cage (7). The outer ring of the secondary planetary gear (12) meshes with the secondary gear ring (5), and the inner ring of the secondary planetary gear (12) meshes with the secondary sun gear (9).

2. The robot joint module with a two-stage planetary deceleration system according to claim 1, characterized in that: The upper end of the secondary sun gear (9) is fixed to the primary planetary cage (18) and radially locked by screws. The outer side of the primary planetary cage (18) is fitted with the primary gear ring (16) to fix the primary front bearing (17) and the primary rear bearing (24). The connecting flange (13) is fixedly connected to the primary gear ring (16). The primary planetary gear (23) is equipped with a needle roller bearing (10) and its inner side meshes with the primary sun gear (22).

3. The robot joint module with two-stage planetary deceleration according to claim 1, characterized in that: The rear end cover (20) is provided with a fixedly connected motor housing (6), and the rear end cover (20) is provided with a drive plate (14) fixed by a hexagonal copper column (21). The motor tail cover (8) is fixed together with the rear end cover (20) and the motor housing (6).

4. The robot joint module with a two-stage planetary deceleration system according to claim 1, characterized in that: The first-stage sun gear (22) is tightly connected to the rotor inner sleeve (26), and a tightly connected rotor is provided on the outside of the rotor inner sleeve (26). The rotor inner sleeve (26) and the rear end cover (20) fix the rotor inner sleeve rear bearing (28), and the rotor inner sleeve (26) and the planetary output T-shaped cylinder (1) fix the output end rear bearing (27).

5. A robot joint module with a two-stage planetary deceleration system according to claim 1, characterized in that: The planetary output T-tube (1) is equipped with several precision pins (2).

6. The robot joint module with a two-stage planetary deceleration system according to claim 1, characterized in that: The surfaces of the first-stage planetary gear (23) and the second-stage planetary gear (12) are provided with planetary gear gaskets (11).

7. A robot joint module with a two-stage planetary deceleration system according to claim 1, characterized in that: A torque motor (15) is also provided between the primary gear ring (16) and the secondary planetary gear (12).

8. A robot joint module with a two-stage planetary deceleration system according to claim 1, characterized in that: The encoder magnet (25) has a code disk (19) on its surface.

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