Combined type planetary gear speed adjusting device

Abstract

The combined type planetary gear speed adjusting device comprises an installation assembly, a sun gear assembly, a planet gear assembly and a flange, the installation assembly is used for installing the sun gear assembly and the planet gear assembly, and the inner side of the flange is in transmission connection with the sun gear assembly through the planet gear assembly; the planet wheel assembly is provided with a first gear part and a first friction transmission part; the sun gear assembly is provided with a second gear part and a second friction transmission part; the first gear part and the second gear part are assembled in a meshed mode, the second friction transmission part and the first friction transmission part are in friction transmission connection, and the first friction transmission part and the flange are in friction transmission connection. The performance of the speed adjusting device can be obviously improved, and the speed adjusting device in the scheme has the advantages of overload protection, small return difference, large transmission torque and long service life.

Description

Technical Field

[0001] The invention relates to a planetary gear, in particular to a compound planetary gear speed regulating device. Background Art

[0002] Friction reducer is a transmission device that uses friction to transmit motion or power. Since motion or power is transmitted only through friction instead of gear teeth, compared with gear reducer, friction reducer has the characteristics of low noise and zero backlash; more importantly, friction reducer has the characteristic of overload protection.

[0003] For friction reducers, the key is whether sufficient normal force can be generated on the contact surface; some patents, such as patent JP2005264969A, specially designed complex planetary brackets in order to generate sufficient friction between the planetary rollers and the sun shaft and the fixed roller ring, which leads to increased size, weight and cost.

[0004] Another example is patent DE19951988B4, which invented a single-stage gearless planetary reducer, which has a relatively small transmission ratio and low output torque. In addition, since the gearless planetary gear uses a bearing to cooperate with the planetary bracket, the bearing is easily damaged when the gearless planetary gear is squeezed. Therefore, the current friction reducer mainly has the problems of complex structure, low transmission torque and easy extrusion loss.

[0005] Therefore, it is necessary to propose a new structure to improve the performance of the reducer. Summary of the invention

[0006] In order to solve the above technical problems, the present invention proposes a compound planetary gear speed regulating device, which can significantly improve the performance of the speed regulating device. The speed regulating device in this scheme has the advantages of overload protection, small backlash, large transmission torque and long service life.

[0007] Specifically, the present invention proposes a compound planetary gear speed regulating device, comprising: a mounting assembly, a sun gear assembly, a planetary gear assembly and a flange, wherein the mounting assembly is used to mount the sun gear assembly and the planetary gear assembly, and the inner side of the flange is drivingly connected to the sun gear assembly through the planetary gear assembly;

[0008] The planetary gear assembly has a first gear portion and a first friction transmission portion;

[0009] The sun gear assembly has a second gear portion and a second friction transmission portion;

[0010] The first gear portion is meshed and assembled with the second gear portion, the second friction transmission portion is frictionally connected to the first friction transmission portion, and the first friction transmission portion is frictionally connected to the flange.

[0011] Preferably, the first friction transmission part is cylindrical and has a hollow structure.

[0012] Preferably, the first friction transmission part and the first gear part are integrally formed.

[0013] Preferably, the side wall thickness of the first gear part is greater than that of the first friction transmission part.

[0014] Preferably, the number of the planetary gear assemblies is not less than three, and each planetary gear assembly has a planetary shaft, and the first gear part is mounted on the planetary shaft through a first bearing.

[0015] Preferably, the two first gear parts are located at both ends in the axial direction of the first friction transmission part; or, the two first friction transmission parts are located at both ends in the axial direction of the first gear part.

[0016] Preferably, the sun gear assembly further has a cylinder, and the second gear part is coaxially fixed on the cylinder; the second friction transmission part is cylindrical and sleeved on the cylinder.

[0017] Preferably, the second friction transmission part and the cylinder are in clearance fit.

[0018] Preferably, the mounting assembly includes a first planetary bracket, a second planetary bracket and an inner ring assembly.

[0019] The first planetary bracket and the second planetary bracket are respectively mounted in the inner ring assembly through second bearings.

[0020] The sun gear assembly is respectively rotatably connected to the first planetary bracket and the second planetary bracket.

[0021] The two ends of the planetary shaft of the planetary gear assembly are respectively fixedly connected to the first planetary bracket and the second planetary bracket.

[0022] The flange and the inner ring assembly are coaxially arranged.

[0023] Preferably, the flange is rotatably connected to the inner ring assembly through a fourth bearing.

[0024] The inner ring assembly includes a plurality of inner rings, and a third gear part for meshing with the first gear part is provided on the inner ring. Description of the Drawings

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art.

[0026] Figure 1It is a schematic three-dimensional structure diagram of the compound planetary gear speed regulation device proposed in this embodiment;

[0027] Figure 2 It is a schematic internal structure diagram of the compound planetary gear speed regulation device in this embodiment;

[0028] Figure 3 It is the front view of the compound planetary gear speed regulation device proposed in this embodiment;

[0029] Figure 4 It is Figure 3 the sectional view in the A-A direction in

[0030] Figure 5 It is Figure 3 the sectional view in the B-B direction in

[0031] Figure 6 It is the front view of the planetary gear assembly in this embodiment;

[0032] Figure 7 It is Figure 6 the sectional structure schematic diagram in the C-C direction in

[0033] Figure 8 It is the front view of the sun gear assembly in this embodiment;

[0034] Figure 9 It is Figure 8 the sectional structure schematic diagram in the D-D direction in

[0035] The reference numerals involved in the drawings are as follows:

[0036] 11 - mounting assembly; 12 - sun gear assembly; 13 - planetary gear assembly; 14 - flange; 15 - first gear part; 16 - first friction drive part; 17 - second gear part; 18 - second friction drive part; 19 - hollow structure; 20 - planetary shaft; 21 - first bearing; 22 - cylinder; 23 - first planetary bracket; 24 - second planetary bracket; 25 - inner ring; 26 - fourth bearing; 27 - third gear part; 28 - second bearing; 29 - third bearing. Specific embodiments

[0037] The technical solutions of the present application will be further described below in conjunction with specific embodiments, but the present application is not limited to these embodiments.

[0038] As Figures 1 to 9As shown in the figure, this embodiment proposes a compound planetary gear speed regulating device, including: a mounting assembly 11, a sun gear assembly 12, a planetary gear assembly 13, and a flange 14. The mounting assembly 11 is used to mount the sun gear assembly 12 and the planetary gear assembly 13. The inner side of the flange 14 is drivingly connected to the sun gear assembly 12 through the planetary gear assembly 13;

[0039] The planetary gear assembly 13 has a first gear portion 15 and a first friction drive portion 16;

[0040] The sun gear assembly 12 has a second gear portion 17 and a second friction drive portion 18;

[0041] The first gear portion 15 is meshed and assembled with the second gear portion 17, the second friction drive portion 18 is frictionally drivingly connected to the first friction drive portion 16, and the first friction drive portion 16 is frictionally drivingly connected to the flange 14.

[0042] The technical effect of this solution is that it can significantly improve the performance of the speed regulating device. The speed regulating device in this solution has the advantages of overload protection, small backlash, large transmitted torque, and high service life. The principle of the specific performance improvement is as follows:

[0043] Principle of overload protection: In this solution, a compound drive method of gear meshing and friction meshing is adopted to achieve power transmission. Since a friction meshing assembly relationship is adopted between the flange 14 and the first friction drive portion 16, it effectively serves the purpose of overload protection, avoiding the development of an overload protection control module for the system, and can effectively reduce the weight, volume, and production cost of the system. Among them, the flange 14 in this solution is used to mount the output shaft or the input shaft through a connection structure. In addition, the technical term friction meshing in this solution refers to: achieving power transmission through friction.

[0044] Principle of small backlash: In order to achieve a large transmission ratio, the gears in the prior art are designed in multiple stages, and the superposition of multiple-stage gears will cause the clearance effect of the gears to be superimposed as well. Therefore, there will be a large backlash in the prior art, which will reduce the transmission accuracy. In this solution, a two-stage drive method of gear meshing and friction meshing is adopted, which can achieve a transmission ratio of 1000:1 and has the advantage of fewer series stages. The double effect of friction drive and gear meshing drive in this solution can significantly reduce the backlash.

[0045] Principle of large transmitted torque: Friction drive realizes motion and power transmission through a pressing force. In comparison with the same volume of gear drive, the transmitted torque of friction drive is smaller; while the first stage of the tooth-engaging - friction compound planetary reducer in this solution adopts a gear meshing technical solution, which can significantly increase the transmitted torque.

[0046] Principle of high service life: In the prior art, friction drive realizes the transmission of motion or power through the pressing force. Among its components, especially the bearings, there will be a large pre-tightening force, resulting in insufficient service life. In this solution, a tooth-engagement - friction composite solution is adopted, that is, a technical solution combining gear engagement and friction drive. Bearings do not need to be installed at the position of the friction drive, which helps to improve the service life of the device.

[0047] As an implementation manner of this embodiment, as Figure 6 and Figure 7 shown, the first friction drive part 16 is cylindrical, and the first friction drive part 16 has a hollow structure 19.

[0048] The technical effect of this solution is as follows: It is used to make the cylindrical shell of the first friction drive part 16 easier to deform, prompting the friction contact surface to fit tightly, which is beneficial to the transmission of motion and power; the planetary gear assembly 13 is made of alloy steel with relatively high stiffness, which is used to make the first friction drive part 16 easily pressed by the second friction drive part 18 and the flange 14, so as to generate sufficient friction force, and then transmit the rotational motion of the sun gear assembly 12 to the output shaft of the flange 14.

[0049] As an implementation manner of this embodiment, the first friction drive part 16 and the first gear part 15 are integrally formed and made of alloy steel with relatively high stiffness.

[0050] Furthermore, the side wall thickness of the first gear part 15 is greater than the side wall thickness of the first friction drive part 16. The technical effect of this solution is as follows: It is used to make the first friction drive part 16 easier to be compressed and deformed, while the first gear part 15 is not easily compressed and deformed, which can significantly improve the transmission performance.

[0051] Furthermore, the planetary gear assembly 13 has a planetary shaft 20, and the first gear part 15 is installed on the planetary shaft 20 through a first bearing 21. Among them, the first bearing 21 adopts a deep groove ball bearing.

[0052] In this solution, the number of the planetary gear assemblies 13 is different under different output torques. When the output torque is small, the number of the planetary gear assemblies 13 will be less, but not less than three.

[0053] Furthermore, for the farthest point on the circumferential surface of the first friction drive part 16 away from the axis of the sun gear assembly 12, the distance between this point and the axis of the sun gear assembly 12 is greater than the radius of the circle where the inner wall of the flange 14 is located.

[0054] As an implementation manner of this embodiment, two first gear parts 15 are located at both ends in the axial direction of the first friction drive part 16; or, two first friction drive parts 16 are located at both ends in the axial direction of the first gear part 15.

[0055] As an implementation manner of this embodiment, the sun gear assembly 12 further has a cylinder 22, and the second gear portion 17 is coaxially fixed on the cylinder 22; the second friction transmission portion 18 is cylindrical, and the second friction transmission portion 18 is sleeved on the cylinder 22.

[0056] As an implementation manner of this embodiment, the second friction transmission portion 18 and the cylinder 22 are in clearance fit.

[0057] As an implementation manner of this embodiment, the mounting assembly 11 includes a first planetary bracket 23, a second planetary bracket 24 and an inner ring assembly.

[0058] The first planetary bracket 23 and the second planetary bracket 24 are respectively installed in the inner ring assembly through second bearings 28.

[0059] The sun gear assembly 12 is respectively rotationally connected to the first planetary bracket 23 and the second planetary bracket 24 through third bearings 29.

[0060] Both ends of the planetary shaft 20 of the planetary gear assembly 13 are respectively fixedly connected to the first planetary bracket 23 and the second planetary bracket 24 through bolts.

[0061] The flange 14 and the inner ring assembly are coaxially arranged.

[0062] Further, there are two inner rings 25 in the inner ring assembly. Further, both ends of the flange 14 along its own axis direction are respectively installed between the two inner rings 25 through fourth bearings 26. One inner ring 25 installs the first planetary bracket 23 through a bearing, and the other inner ring 25 installs the second planetary bracket 24 through a bearing. Sealing rings are provided at the assembly positions of the inner ring assembly and the first planetary bracket 23 and the second planetary bracket 24. Among them, the fourth bearing 26 can adopt a thrust bearing.

[0063] Further, a third gear portion 27 for meshing with the first gear portion 15 is further provided on the inner ring 25. When the motor drives the sun gear assembly 12 to rotate, the planetary gear assembly 13 will, under the drive of the sun gear assembly 12, rotate while revolving, and push the flange 14 to rotate through friction, so as to realize the transmission of motion or power; among them, the motor is not shown in the drawings.

[0064] Since the first gear portion 15 meshes with the second gear portion 17, and the first gear portion 15 meshes with the third gear portion 27 of the inner ring 25, the situation of slipping is avoided, and the first friction transmission portion 16 and the flange 14 belong to friction transmission, and sliding will occur when the acting load is greater than the frictional force, thus playing a role in overload protection.

[0065] Specific working process: The sun gear assembly 12 rotates driven by the motor. The second gear part 17 meshes with and drives the first gear part 15. Since the inner ring assembly is fixed, the planetary gear assembly 13 will rotate on its own axis and at the same time drive the first planetary bracket 23, the second planetary bracket 24 and the planetary shaft 20 to rotate. The first friction drive part 16 drives the flange 14 to rotate through the extrusion of the second friction drive part 18. The flange 14, as the output component, realizes the function of speed reduction and torque increase. Since the whole transmission is realized by gear meshing and frictional drive, it can perform a non-backlash movement more strictly, thus improving the transmission efficiency and realizing the function of overload protection. Moreover, in the gear-engaging - friction compound planetary reducer, only the first friction drive part 16 of the planetary gear transfers motion through elastic deformation and friction. Since it is hollow inside and does not require a bearing for support, it can avoid the extrusion of the first friction drive part 16 on the bearing due to deformation, thereby increasing the service life of the reducer.

[0066] In addition, by changing the gear parameters of the sun gear assembly 12, the inner ring assembly and the planetary gear assembly 13 and the diameter of the first friction drive part 16 of the planetary gear assembly 13, a transmission ratio from 5:1 to 1000:1 can be achieved, so it has a wide range of application prospects.

[0067] In general, in this solution, the sun gear assembly 12 is used as the input stage, the flange 14 is used as the output stage, and the inner ring 25 is fixed.

[0068] In addition, according to needs, the flange 14 can also be used as the input stage and the sun gear as the output stage.

[0069] Actually, since the gear-engaging - friction compound planetary reducer is similar to planetary transmission, any one of the cylinder 22 of the sun gear assembly 12, the flange 14 and the planetary brackets can be fixed, and the other two can be used as the input stage and the output stage respectively. Of course, sometimes it can also be made into a differential form. The planetary brackets in this article refer to the first planetary bracket 23 and the second planetary bracket 24.

[0070] In addition, the design parameters among the first gear part 15, the first gear part 15 and the third gear part 27 of the inner ring 25 need to meet the conditions of planetary reducer transmission.

[0071] Although the embodiments of the present invention have been discussed above, the present invention is not limited to this specific embodiment and can be varied in many ways without departing from the original intention of the invention.

[0072] For those of ordinary skill in the art, without departing from the inventive concept of the present invention, several deformations and improvements can still be made, and these all fall within the protection scope of the present invention.

Claims

1. A compound planetary gear speed regulating device, characterized in that: include: A mounting assembly (11), a sun gear assembly (12), a planetary gear assembly (13) and a flange (14), wherein the mounting assembly (11) is used to mount the sun gear assembly (12) and the planetary gear assembly (13), and the inner side of the flange (14) is drivingly connected to the sun gear assembly (12) via the planetary gear assembly (13); The planetary gear assembly (13) comprises a first gear portion (15) and a first friction transmission portion (16); The sun gear assembly (12) has a second gear portion (17) and a second friction transmission portion (18); The first gear part (15) is meshed with the second gear part (17), the second friction transmission part (18) is frictionally connected to the first friction transmission part (16), and the first friction transmission part (16) is frictionally connected to the flange (14).

2. The compound planetary gear speed regulating device according to claim 1, characterized in that: The first friction transmission part (16) is cylindrical, and the first friction transmission part (16) has a hollow structure (19).

3. The compound planetary gear speed regulating device according to claim 2, characterized in that: The first friction transmission part (16) and the first gear part (15) are integrally formed.

4. The compound planetary gear speed regulating device according to any one of claims 1 to 3, characterized in that: The thickness of the side wall of the first gear portion (15) is greater than the thickness of the side wall of the first friction transmission portion (16).

5. The compound planetary gear speed regulating device according to any one of claims 1 to 3, characterized in that: The number of the planetary gear assemblies (13) is not less than three, and each of the planetary gear assemblies (13) has a planetary shaft (20), and the first gear part (15) is mounted on the planetary shaft (20) via a first bearing (21).

6. The compound planetary gear speed regulating device according to any one of claims 1 to 3, characterized in that: The two first gear parts (15) are located at two ends of the first friction transmission part (16) in the axial direction; or, the two first friction transmission parts (16) are located at two ends of the first gear part (15) in the axial direction.

7. The compound planetary gear speed regulating device according to claim 1, characterized in that: The sun gear assembly (12) also has a column (22), and the second gear portion (17) is coaxially fixed on the column (22); the second friction transmission portion (18) is cylindrical, and the second friction transmission portion (18) is sleeved on the column (22).

8. The compound planetary gear speed regulating device according to claim 7, characterized in that: The second friction transmission part (18) is clearance-matched with the column (22).

9. The compound planetary gear speed regulating device according to claim 1, characterized in that: The mounting assembly (11) comprises a first planetary support (23), a second planetary support (24) and an inner ring assembly. The first planet carrier (23) and the second planet carrier (24) are respectively installed in the inner ring assembly through second bearings (28); The sun gear assembly (12) is rotatably connected to the first planetary support (23) and the second planetary support (24) respectively; The two ends of the planet shaft (20) of the planetary gear assembly (13) are respectively firmly connected to the first planet bracket (23) and the second planet bracket (24); The flange (14) is coaxially arranged with the inner ring assembly.

10. The compound planetary gear speed regulating device according to claim 9, characterized in that: The flange (14) is rotatably connected to the inner ring assembly via a fourth bearing (26); The inner ring assembly comprises a plurality of inner rings (25), and a third gear portion (27) is provided on the inner ring (25) for meshing with the first gear portion (15).

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