Planetary gear reducers and vehicles

Abstract

This utility model relates to a planetary gear reducer with high noise control requirements, comprising a housing and a planetary gear assembly. The housing has an internal spline for fixing the planetary gear assembly. The planetary gear assembly has a gear ring and planetary gears. A spline engagement mechanism is provided on the radial outer circumference of the gear ring, wherein the spline engagement mechanism consists of paired elastic protrusions that can clamp the internal spline. This utility model aims to solve the problem in the prior art where the rigid connection between the planetary gear assembly and the reducer housing causes unbuffered transmission of internal vibrations to the outside of the reducer, thereby reducing noise, minimizing component fatigue damage, and improving service life and reliability.

Description

Technical Field

[0001] This utility model relates to a planetary gear reducer, and more particularly to a planetary gear reducer with high noise limitation requirements. Background Technology

[0002] With the rapid development of the automotive industry, modern cars have increasingly higher requirements for noise control during operation. In-vehicle noise levels not only directly affect passenger comfort but are also a crucial indicator of vehicle quality. In the automotive powertrain system, the gear reducer, as a key component, has received widespread attention due to the vibration and noise issues it generates during operation.

[0003] like Figure 1 As shown, in existing gear reducer structures, the planetary gear ring is typically connected to the reducer housing via an outer spline. This connection allows vibrations generated during planetary gear operation to be transmitted unimpeded through the planetary gear ring to the reducer housing, and then directly to the vehicle body. The vehicle body, acting as the vibration propagation carrier, further amplifies these vibrations and transmits them into the vehicle interior, leading to increased noise levels and severely impacting the vehicle's quietness and ride comfort. Furthermore, long-term vibration transmission can cause fatigue damage to related vehicle components, affecting the vehicle's lifespan and reliability. Therefore, effectively reducing the transmission of vibrations from the gear reducer to the reducer housing during operation has become a pressing technical problem in the automotive industry. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide an improved planetary gear reducer, which can effectively reduce the vibration transmitted from the planetary gear system to the reducer housing.

[0005] The aforementioned technical problem is solved by a planetary gear reducer designed according to this utility model. This planetary gear reducer has a housing and a planetary gear assembly. An internal spline for fixing the planetary gear assembly is provided on the radially inner side of the housing. The planetary gear assembly has a gear ring and planetary gears. A spline engagement mechanism for rotating and fixing the gear ring is provided on the radially outer circumferential surface of the gear ring. In this utility model, the spline engagement mechanism can be designed as paired elastic protrusions, which can respectively clamp the internal spline. This technical solution avoids the traditional spline connection between the planetary gear assembly and the reducer housing. The elastic protrusions generate a damping effect, reducing the noise transmitted from the planetary gear assembly to the reducer housing, which helps improve vehicle quietness and ride comfort. It also saves on sound insulation materials originally placed in the engine compartment, chassis, etc., thus reducing production costs.

[0006] According to a preferred embodiment of this utility model, the distance between the elastic protrusions belonging to the same pair is less than the circumferential width of the internal spline. This structure achieves an interference fit between the elastic protrusions and the internal spline, avoiding connection gaps and thus reducing noise caused by collisions at the connection points during gearbox operation. More preferably, a groove is formed within the circumferential interval between two adjacent pairs of elastic protrusions, and a spring can be installed within the groove. By setting a groove or installing a spring within the groove, the spring effect of the elastic protrusions can be enhanced, more effectively reducing noise transmission. Even more preferably, the circumferential width of the groove is less than half the circumferential width of the internal spline. This allows for clear differentiation between the groove and the interior of the paired elastic protrusions during installation, preventing component damage due to incorrect installation and improving assembly efficiency. Of course, the circumferential width of the groove can also be greater than twice the circumferential width of the internal spline, as long as the groove and the interior of the paired elastic protrusions are clearly distinguishable.

[0007] According to a preferred embodiment of this utility model, a retaining ring groove for placing an elastic retaining ring is provided on the radially inner side of the housing and the axially outer side of the internal spline. The gear ring is axially fixed to the housing by the elastic retaining ring. This structure effectively restricts the relative movement of the gear ring in the axial direction, reduces the axial clearance of the overall structure, and avoids noise caused by axial collision. More preferably, both ends of the elastic retaining ring are provided with lugs, and mounting holes are provided on the lugs. By providing lugs and mounting holes, the elastic retaining ring can be installed more conveniently using corresponding snap ring pliers, improving assembly efficiency.

[0008] According to a preferred embodiment of this utility model, the internal teeth of the gear ring are designed as helical teeth. This design results in higher load-bearing capacity and contact ratio between the gear ring and the planetary gears. Furthermore, compared to spur gears, helical teeth operate more smoothly and quietly. If the reducer operates in one direction, this configuration can also generate an inward axial force on the gear ring, further securing it axially to the reducer housing. More preferably, the central axis of the internal spline and the elastic protrusion has an inclination angle relative to the axis of the planetary gear assembly, and this inclination angle is opposite to the rotation angle of the internal teeth of the gear ring. Through the mechanical cancellation effect of the opposing rotation angles, the axial forces generated by the meshing of the internal and external components of the planetary gear reducer are theoretically balanced, and the total axial resultant force approaches zero. This solution completely eliminates the risk of axial displacement caused by the internal meshing of the helical teeth in the gear ring, thus eliminating the need to rely entirely on traditional retaining ring structures. This simplifies the overall structure of the gearbox, reduces manufacturing costs and assembly complexity, and significantly improves the reliability of the transmission system.

[0009] Based on the above-mentioned reducer design, the technical problem of this utility model can also be solved by a vehicle. After the vehicle is equipped with a planetary gear reducer with the above-mentioned features, the vibration transmitted from the inside of the reducer to the housing is greatly reduced, thereby reducing the vibration transmitted to the vehicle interior, reducing the noise level inside the vehicle, improving the quietness and ride comfort of the vehicle, and at the same time reducing fatigue damage to related parts of the vehicle caused by vibration, thereby improving the service life and reliability of the vehicle. Attached Figure Description

[0010] The present invention will now be described in more detail with reference to the accompanying drawings, but this does not limit the overall concept of the invention.

[0011] Figure 1 An exploded view of the assembly method of the gear ring and housing in a planetary gear reducer in the prior art;

[0012] Figure 2 This is an exploded view showing the assembly method of the gear ring and the housing of this utility model;

[0013] Figure 3 This is a partial radial cross-sectional view of the gear ring of this utility model;

[0014] Figure 4 This is a partially enlarged view of the assembly relationship between the gear ring and the housing of this utility model.

[0015] In this utility model, unless otherwise specified, "axial", "radial" and "circumferential" are all relative to the planetary gear reducer. Detailed Implementation

[0016] Figure 1 The diagram illustrates the assembly method of a planetary gear reducer ring gear 2' to a housing 1' in the prior art. In this reducer, the planetary gear ring gear 2' is connected to the housing 1' via an inner spline 11' located radially outward. This connection method allows vibrations generated during planetary gear operation to be transmitted unimpeded through the planetary gear ring gear 2' to the housing 1', and then directly to the vehicle body. The vehicle body, acting as a vibration propagation carrier, further amplifies these vibrations and transmits them into the vehicle interior, leading to increased interior noise levels and severely impacting the vehicle's quietness and ride comfort. Furthermore, long-term vibration transmission can cause fatigue damage to related vehicle components, affecting the vehicle's service life and reliability.

[0017] Figure 2 The assembly method of the gear ring 2 and the housing 1 according to the present invention is shown. In this assembly method, an internal spline 11 is provided on the radially inner side of the housing 1, and a spline mating mechanism 21 is provided on the radially outer circumferential surface of the gear ring 2 at a position corresponding to the internal spline 11. Figure 2In this embodiment, the spline mating mechanism 21 includes a pair of elastic protrusions 211. During actual assembly, when the gear ring 2 is installed into the housing 1, the pairs of elastic protrusions 211 respectively mate with the inner spline 11, tightly clamping the inner spline 11. Since the distance between the elastic protrusions 211 belonging to the same pair is slightly smaller than the circumferential width of the inner spline 11, this tight fit effectively avoids connection gaps and reduces noise caused by collisions at the connection points during the operation of the reducer.

[0018] Figure 3 A partial radial cross-sectional view of the gear ring 2 of this invention is shown. A slot 22 is formed within the circumferential interval between two adjacent pairs of elastic protrusions 211, which enhances the spring effect of the elastic protrusions and more effectively reduces vibration transmission. More preferably, a spring sheet can be provided within the slot 22, which further enhances the spring effect of the elastic protrusions, further reduces vibration transmission, and thus reduces noise. Furthermore, the circumferential width of the slot 22 is less than half the circumferential width of the inner spline 11. Figure 3 In the illustrated embodiment, the circumferential width of the slot 22 is 7mm and the circumferential width of the inner spline is 15mm. When assembling workers perform installation operations, they can clearly distinguish the slot 22 from the interior of the paired elastic protrusions 211 used to clamp the inner spline 11, thus avoiding damage to components due to installation errors and improving assembly efficiency.

[0019] Figure 4 This diagram shows a partially enlarged view of the assembly relationship between the gear ring and the housing of this utility model. Figure 2 As can be seen, the housing 1 has a retaining ring groove 12 on its radial inner side and the axial outer side of the inner spline 11 for placing the elastic retaining ring 3. The gear ring 2 is axially fixed to the housing 1 by the elastic retaining ring 3, which effectively restricts the relative movement of the gear ring 2 in the axial direction, reduces the axial clearance of the overall structure, and avoids noise caused by axial collision.

[0020] exist Figure 2 , 3 In the embodiment shown in Figure 4, the elastic retaining ring 3 is a notched ring without lugs at both ends. During assembly, an inward force is applied to the elastic retaining ring 3, causing it to elastically deform and reduce in diameter, allowing it to be installed into the retaining ring groove 12. When the external force is removed, the elastic retaining ring 3 elastically returns to its original size, thus locking itself into the retaining ring groove 12. In addition to this embodiment, the elastic retaining ring 3 may have lugs at both ends with mounting holes. When installing the elastic retaining ring 3, the assembly worker can use appropriate snap ring pliers, inserting the pliers' heads into the mounting holes to easily install the elastic retaining ring 3 into the retaining ring groove 12, greatly improving assembly efficiency.

[0021] exist Figure 2 , 3In the embodiment shown in Figure 4, the internal teeth 23 of the gear ring 2 are designed as helical teeth. Compared with spur teeth, the bearing capacity and contact ratio between the gear ring 2 and the planetary gears are higher during actual operation of the planetary gear reducer, resulting in smoother and quieter operation. If the reducer operates in one direction, the helical teeth can also generate an inward axial force on the gear ring 2, further fixing the gear ring 2 axially to the reducer housing 1. Furthermore, the central axes of the internal spline 11 and the elastic protrusion 211 have an inclination angle relative to the axis of the planetary gear assembly, and this inclination angle is opposite to the rotation angle of the internal teeth 23 of the gear ring 2. During actual operation, the axial forces generated by the meshing of the inner and outer components of the gear ring 2 of the planetary gear reducer are theoretically balanced, and the total axial resultant force approaches zero. This design completely eliminates the risk of axial displacement caused by the internal meshing of the helical teeth in the gear ring 2, eliminates the need to rely entirely on the traditional retaining ring limiting structure, simplifies the overall structure of the gearbox, reduces manufacturing costs and assembly complexity, and significantly improves the reliability of the transmission system. Figure 2 , 3 In addition to the embodiment shown in Figure 4, the internal tooth 23 can also be designed as a straight tooth. Compared with helical teeth, straight teeth are simpler to design and easier to manufacture, which helps to reduce manufacturing costs. Furthermore, straight teeth have higher transmission efficiency than helical teeth, which is beneficial for energy conservation and environmental protection.

[0022] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

[0023] List of reference numerals

[0024] 1, 1' Shell

[0025] 11' internal splines

[0026] 12 retaining ring grooves

[0027] 2, 2' gear ring

[0028] 21 Spline mating mechanism

[0029] 211 Elastic protrusion

[0030] 22 Empty slots

[0031] 3. Elastic retaining ring

Claims

1. A planetary gear reduction, comprising a housing (1) and a planetary gear device, an inner spline (11) for fixing the planetary gear device being provided on the radially inner side of the housing (1), the planetary gear device having a ring gear (2) and planet wheels, wherein A spline engagement mechanism (21) for rotating and fixing the gear ring (2) is provided on the radial outer circumferential surface of the gear ring (2). The spline engagement mechanism (21) includes a pair of elastic protrusions (211), which respectively clamp the inner spline (11).

2. A planetary gear reducer according to claim 1, characterized in that The distance between the elastic protrusions (211) belonging to the same pair is less than the circumferential width of the inner spline (11).

3. The planetary gear reducer according to claim 1, characterized in that, A groove (22) is formed in the circumferential interval between two adjacent pairs of elastic protrusions (211).

4. A planetary gear reducer according to claim 3, characterised in that, A spring is installed in the empty slot (22).

5. A planetary gear reducer according to claim 3, characterized in that, The circumferential width of the slot (22) is less than half the circumferential width of the inner spline (11).

6. The planetary gear reducer according to claim 1, characterized in that, A retaining ring groove (12) for placing an elastic retaining ring (3) is provided on the radial inner side of the housing (1), and the toothed ring (2) is axially fixed on the housing (1) by the elastic retaining ring (3).

7. The planetary gear reducer according to claim 6, characterized in that, Both ends of the elastic retaining ring (3) are provided with lugs, and mounting holes are provided on the lugs.

8. The planetary gear reducer according to claim 1, characterized in that, The inner tooth portion (23) of the gear ring (2) is designed as a helical tooth.

9. The planetary gear reducer according to claim 8, characterized in that, The central axes of the internal spline (11) and the elastic protrusion (211) have an inclination angle relative to the axis of the planetary gear assembly, and the inclination angle is opposite to the rotation angle of the internal tooth (23).

10. A vehicle having a planetary gear reducer according to any one of claims 1 to 9.

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