A planetary cycloidal gear reducer

Abstract

This utility model provides a planetary cycloidal gear reducer, mainly relating to the field of robot reducers. The planetary cycloidal gear reducer comprises a two-stage reduction mechanism consisting of a cycloidal gear and planetary gears. The cycloidal gear reduction mechanism eliminates interference by positively increasing the gear ring displacement coefficient or negatively increasing the cycloidal gear displacement coefficient, along with appropriate adjustments to the tooth tip and tooth root heights. The planetary gear reduction mechanism comprises: a planetary gear ring, a star gear carrier, a star gear shaft, planetary gears, and a sun gear. The star gear shaft is assembled and fixed to the planetary gears via rolling elements, and then interference-fitted and riveted to the star gear shaft hole on the star gear carrier to prevent dislodgement. The planetary gear ring is concentrically fixed to the cycloidal gear ring. The sun gear is fixed to the reducer's front end cover via bearings and then assembled and fixed to the cycloidal gear ring. This forms a novel planetary cycloidal gear robot reducer.

Description

Technical Field

[0001] This utility model mainly relates to the field of robot reducers, specifically a planetary cycloidal gear reducer. Background Technology

[0002] Invention Patent No. ZL201510676854.6, "A Precision Speed ​​Reduction Transmission Mechanism," solved the interference problem of involute gear and cycloidal gear transmission by adjusting the pressure angle and tooth tip height of the involute gear, bringing a new type of cycloidal gear reducer to the robotics industry and solving many problems existing in other types of reducers in the industry. However, with the large-scale promotion and application in the market, some defects and problems have also been exposed, affecting the superior performance of this new type of cycloidal gear reducer. There are two main problems: First, the multiple cycloidal crankshafts are too evenly distributed around the circumference, which is not conducive to the miniaturization of the reducer. The first-stage parallel shaft reduction mechanism composed of the central gear and the cycloidal crankshaft gear is installed at the outer end of the output flange through the cycloidal gear, making the mechanism too complex and increasing the manufacturing difficulty and cost. Second, relying on changing the meshing pressure angle and tooth tip height of the cycloidal gear and gear ring to eliminate gear interference at large transmission ratios results in a shallow meshing depth between the gear and gear ring, which greatly limits the output torque. These two points greatly affect the performance of this type of reducer and limit its wider promotion. Utility Model Content

[0003] To address the shortcomings of existing technologies, this utility model provides a planetary cycloidal gear reducer to solve the problems mentioned in the background section.

[0004] To achieve the above objectives, this utility model employs the following technical solution:

[0005] A planetary cycloidal gear reducer includes a reducer housing, a cycloidal gear ring, a reducer input end cover, and an output flange. The reducer input end cover, the cycloidal gear ring, and the reducer housing are fixedly installed in sequence. The output flange is rotatably connected to the reducer housing and the cycloidal gear ring. A centering shaft is fixedly mounted on the output flange. An input shaft is rotatably mounted at the center of the reducer input end cover. A sun gear is mounted on the input shaft. A planetary gear ring is disposed between the reducer input end cover and the cycloidal gear ring. A star gear carrier, a first cycloidal gear, and a second cycloidal gear are progressively disposed between the reducer input end cover and the output flange. The star gear carrier has several star gear shafts evenly arranged in a circle, and planetary gears are rotatably mounted on the star gear shafts. The planetary gears mesh with the sun gear and the planetary ring gear. A cycloidal crankshaft is coaxially fixed on the star gear carrier and is rotatably mounted on the centering shaft. The first cycloidal gear and the second cycloidal gear are rotatably connected to the cycloidal crankshaft through integrated eccentric rolling elements. The output flange has several actuating pins evenly arranged in a circle, and the first cycloidal gear and the second cycloidal gear are each provided with actuating holes corresponding to the actuating pins. The actuating pins pass through the actuating holes of the first cycloidal gear and the second cycloidal gear.

[0006] The output flange is coaxial with the centering shaft, and the output flange and the centering shaft are integrally formed.

[0007] The output flange is coaxially mounted at the contact point between the cycloidal gear ring and the reducer housing via crossed rolling elements.

[0008] The sun gear, cycloidal gear ring, and planetary gear ring are coaxial.

[0009] The star wheel frame is interference-fitted with the input end of the cycloidal crankshaft through its through hole, and the two are then fastened together by riveting.

[0010] The actuating pins are provided in 6 to 18 locations on the output flange.

[0011] Compared with the existing technology, the beneficial effects of this utility model are:

[0012] The most significant feature of this invention is the axial grafting of a cycloidal gear reduction mechanism and a planetary gear reduction mechanism to form a new combination. This maximizes the advantages of both reduction mechanisms, creating a complementary and synergistic effect. The result is a compact and tightly coupled structure with a smaller overall size, higher rigidity, and a geometrically increased output torque density. The small and lightweight sun gear of the planetary gear reduction mechanism, when directly connected to the motor shaft, can smoothly and efficiently reduce the high speed of the motor to 1 / 3-1 / 5. This lowers the transmission ratio requirement of the cycloidal gear mechanism, allowing for the selection of an ideal gear module and meshing depth. Consequently, the torque output density of this high-ratio, high-rigidity reduction mechanism is greatly enhanced, resulting in a doubling of the output torque.

[0013] This invention offers more stable operation, significantly improved precision and rigidity, and a wider range of specifications and models, making it applicable to a broader range of fields. Its widespread adoption will provide a superior core component for the industrial robot and humanoid robot industries, greatly promoting faster and higher-quality development in these sectors. Attached Figure Description

[0014] Appendix Figure 1 This is a schematic diagram of the structure of this utility model.

[0015] The following are the reference numerals in the attached diagram: 1. Reducer housing; 2. Cycloidal gear ring; 3. Output flange; 4. Actuating pin; 5.1. First cycloidal gear; 5.2. First cycloidal gear; 6. Integrated eccentric rolling element; 7. Integrated centering rolling element; 8. Cycloidal crankshaft; 9. Centering shaft; 10. Star gear carrier; 11. Star gear shaft; 12. Planetary gear; 13. Planetary gear ring; 14. Sun gear; 15. Reducer input end cover; 16. Motor. Detailed Implementation

[0016] The present invention will be further described in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the present invention, and these equivalent forms also fall within the scope defined in this application.

[0017] As shown in the figure, this utility model discloses a planetary cycloidal gear reducer. The reducer comprises a two-stage reduction mechanism consisting of a cycloidal gear and planetary gears. The cycloidal gear reduction mechanism is fundamentally different from the invention patent "A Precision Reduction Transmission Mechanism." Instead of eliminating interference solely by changing the pressure angle and tooth tip height of the involute gear, it eliminates interference by positively increasing the gear ring displacement coefficient or negatively increasing the cycloidal gear displacement coefficient, along with appropriate adjustments to the tooth tip and tooth root heights. This allows for the selection of ideal gear module and gear meshing depth for each specification in the entire series, resulting in a significant release of torque output density in this type of cycloidal gear reducer, effectively doubling the output torque.

[0018] This reducer includes a reducer housing 1, a cycloidal gear ring 2, a reducer input end cover 15, and an output flange 3. The reducer housing 1, cycloidal gear ring 2, reducer input end cover 15, and output flange 3 form a sealed structure, with an internal installation space. The reducer input end cover 15, cycloidal gear ring 2, and reducer housing 1 are sequentially fixed and connected as a whole by fastening bolts. The inner wall of the cycloidal gear ring 2 has evenly distributed cycloidal teeth for engaging with subsequent cycloidal gears. The output flange 3 is rotatably connected to the reducer housing 1 and cycloidal gear ring 2. In this embodiment, the output flange 3 is coaxially rotatably mounted at the contact point between the cycloidal gear ring 2 and the reducer housing 1 via crossed rolling elements. The crossed rolling elements distribute the rotational load of the output flange 3 across the reducer housing 1 and the cycloidal gear ring 2, making the rotation output from the output flange 3 more stable.

[0019] A centering shaft 9 is fixedly mounted on the output flange 3. The centering shaft 9 serves as a component for the rotatable mounting of the integrated eccentric rolling element 6 described below. Specifically, the output flange 3 and the centering shaft 9 are coaxial and integrally formed, thereby ensuring the rigidity of the output flange 3 and the centering shaft 9 and ensuring power output under high torque.

[0020] An input shaft is rotatably mounted at the center of the input end cover 15 of the reducer. A sun gear 14 is mounted on the input shaft, and a planetary gear ring 13 is positioned between the input end cover 15 and the cycloidal gear ring 2. A star gear carrier 10, a first cycloidal gear 5.1, and a second cycloidal gear 5.2 are progressively arranged between the input end cover 15 and the output flange 3. Several star gear shafts 11 are evenly arranged circumferentially on the star gear carrier 10, and planetary gears 12 are rotatably mounted on the star gear shafts 11. The planetary gears 12 mesh with the sun gear 14 and the planetary gear ring 13. Rotation of the input shaft drives the sun gear 14 to rotate, which in turn drives the planetary gears 12 to rotate, completing the planetary gear reduction step and driving the star gear carrier 10 to rotate. The sun gear 14, the cycloidal gear ring 2, and the planetary gear ring 13 are coaxially arranged.

[0021] A cycloidal crankshaft 8 is coaxially fixed on the star wheel carrier 10. After the central through hole of the star wheel carrier 10 is interference-fitted with the input end of the cycloidal crankshaft 8, the two are fastened together by riveting. The cycloidal crankshaft 8 is rotatably connected to the centering shaft 9. In this embodiment, the cycloidal crankshaft 8 is rotatably mounted to the centering shaft 9 after integrating the centering rolling element 7. The first cycloidal gear 5.1 and the second cycloidal gear 5.2 are both rotatably connected to the cycloidal crankshaft 8 through the integrated eccentric rolling element 6. The first cycloidal gear 5.1 and the second cycloidal gear 5.2 are axially mounted on two eccentric shaft positions of the cycloidal crankshaft 8 that are 180 degrees apart from each other through the integrated eccentric rolling element 6. The rotation is transmitted to the cycloidal crankshaft 8 through the star wheel carrier 10. The rotation of the cycloidal crankshaft 8 drives the first cycloidal gear 5.1 and the second cycloidal gear 5.2 to rotate through the pushing action of the integrated eccentric rolling element 6. The first cycloidal gear 5.1 and the second cycloidal gear 5.2 form a cycloidal transmission relationship with the cycloidal gear ring 2 to obtain further deceleration.

[0022] A plurality of actuating pins 4 are evenly arranged circumferentially on the output flange 3. Both the first cycloidal gear 5.1 and the second cycloidal gear 5.2 have actuating holes corresponding to the actuating pins 4. The diameter of the actuating holes is larger than the diameter of the actuating pins 4, and the actuating pins 4 pass through the actuating holes of the first cycloidal gear 5.1 and the second cycloidal gear 5.2. Through the engagement of the first cycloidal gear 5.1 and the second cycloidal gear 5.2, the decelerated rotational motion is transmitted to the output flange 3 for outputting high-torque rotation. Specifically, 6 to 18 actuating pins 4 are arranged on the output flange 3, selected according to the output torque to ensure the safety of high-torque transmission.

[0023] The working principle of this reducer is as follows: when the motor 16 is powered on, the output shaft of the motor 16 drives the sun gear 14 to rotate. The sun gear 14 reduces the speed through the planetary transmission relationship of the planetary gear 12 and the planetary ring gear 13. Then, through the star gear carrier 10, it drives the cycloidal crankshaft 8 to rotate around the centering shaft 9. Under the action of the two eccentric shafts on the cycloidal crankshaft 8, the two cycloidal gears form a cycloidal transmission relationship with the cycloidal ring gear 2, thereby achieving further deceleration. Then, the meshing actuating pin 4 drives the output flange to rotate, completing the deceleration transmission output.

Claims

1. A planetary cycloidal gear reducer comprising a reducer housing (1), a cycloid ring gear (2), a reducer input end cover (15) and an output flange (3), characterized in that: The reducer input end cover (15), cycloidal gear ring (2), and reducer housing (1) are fixedly installed in sequence. The output flange (3) is rotatably connected to the reducer housing (1) and cycloidal gear ring (2). A centering shaft (9) is fixedly installed on the output flange (3). An input shaft is rotatably installed at the center of the reducer input end cover (15). A sun gear (14) is installed on the input shaft. A planetary gear ring (13) is installed between the reducer input end cover (15) and the cycloidal gear ring (2). A star wheel carrier (10), a first cycloidal gear (5.1), and a second cycloidal gear (5.2) are progressively installed between the reducer input end cover (15) and the output flange (3). Several star wheel shafts (11) are evenly arranged in a circle on the star wheel carrier (10). (11) A planetary gear (12) is rotatably mounted on the planetary gear (12), which meshes with the sun gear (14) and the planetary gear ring (13); a cycloidal crankshaft (8) is coaxially fixed on the star wheel carrier (10), and the cycloidal crankshaft (8) is rotatably mounted with the centering shaft (9). The first cycloidal gear (5.1) and the second cycloidal gear (5.2) are rotatably connected to the cycloidal crankshaft (8) through an integrated eccentric rolling element (6). A number of actuating pins (4) are evenly arranged in a circle on the output flange (3). The first cycloidal gear (5.1) and the second cycloidal gear (5.2) are provided with actuating holes corresponding to the actuating pins (4). The actuating pins (4) pass through the actuating holes of the first cycloidal gear (5.1) and the second cycloidal gear (5.2).

2. A planetary roller gear speed reducer according to claim 1, characterized in that The output flange (3) is coaxial with the centering shaft (9), and the output flange (3) and the centering shaft (9) are integrally formed.

3. A planetary roller gear speed reducer according to claim 1, characterized in that The output flange (3) is coaxially mounted at the contact point between the cycloidal gear ring (2) and the reducer housing (1) via cross rolling elements.

4. A planetary roller gear speed reducer according to claim 1, characterized in that The sun gear (14), cycloidal gear ring (2), and planetary gear ring (13) are coaxial.

5. A planetary roller gear speed reducer according to claim 1, characterized in that After the through hole of the star wheel frame (10) is interference-fitted with the input end of the cycloidal crankshaft (8), the two are fastened together by riveting.

6. A planetary roller gear speed reducer according to claim 1, characterized in that The actuating pins (4) are provided in 6 to 18 units on the output flange (3).

Images