A noise suppression structure for an electric motor drive assembly

Abstract

The utility model relates to motor drive assembly technical field discloses a abnormal sound suppression structure for motor drive assembly, including input shaft, the one end of input shaft is connected with motor shaft, the gear on input shaft is engaged with the gear on intermediate shaft, the gear on intermediate shaft is engaged with differential crown wheel. The utility model can significantly reduce the gear knock abnormal sound under the torque zero condition and the vibration noise of low speed bad road condition, prolong grease retention time, reduce gear wear, improve lubricating property, reduce the meshing impact through optimization tooth side clearance, make torque transmission more stable and continuous, improve transmission smoothness, vibration reduction can improve bearing life, prolong gear fatigue life, and further prolong overall service life, and simultaneously simple structure can realize above -mentioned effect, need not complex and expensive initiative control system, have good cost effectiveness.

Description

Technical Field

[0001] This utility model relates to the field of motor drive assembly technology, specifically to a noise suppression structure for motor drive assemblies. Background Technology

[0002] During the operation of the electric motor drive assembly, a series of technical issues have consistently hindered performance improvement and user experience optimization. Firstly, under conditions of zero torque and low-speed passage through rough roads, the gear meshing system is prone to producing noticeable knocking noises. This not only affects the quietness of equipment operation but may also raise user concerns about equipment stability. Secondly, the relatively large tooth backlash used in traditional designs results in significant impacts during gear meshing, exacerbating instability during transmission. Simultaneously, the lack of effective damping and vibration reduction measures in the gear transmission system causes vibrations and noise to be directly transmitted to the housing, further amplifying the noise problem. Furthermore, the lack of lubrication at the spline joint connection not only accelerates gear wear but also generates more noise due to increased friction, adversely affecting the equipment's lifespan and operational stability. More critically, existing technologies typically employ only single vibration reduction measures, such as simply adding grease or adjusting tooth backlash. This one-sided solution has limited effectiveness and cannot comprehensively and effectively address the aforementioned multiple problems. Utility Model Content

[0003] The purpose of this invention is to address the shortcomings of existing technologies by proposing a noise suppression structure for motor drive assemblies.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a noise suppression structure for a motor drive assembly, comprising an input shaft, one end of which is connected to a motor shaft, a gear on the input shaft meshing with a gear on an intermediate shaft, and a gear on the intermediate shaft meshing with a differential crown wheel.

[0005] As a further description of the above technical solution: Both the input shaft and the motor shaft are equipped with splines inside, and high-performance grease is applied between the splines on the input shaft and the splines inside the motor shaft.

[0006] As a further description of the above technical solution: A sealing plug is provided in the inner hole at the rear end of the input shaft, and a rubber sealing ring is installed in the spline at the front end of the input shaft.

[0007] As a further description of the above technical solution: The outer ring of the intermediate shaft is provided with an annular groove, and a rubber O-ring is provided in the annular groove.

[0008] As a further description of the above technical solution: The crossbar spacing of the differential crown wheel is increased, and the parameters of the secondary gear are adjusted accordingly to reduce the meshing backlash.

[0009] As a further description of the above technical solution: The clearance between the differential crown wheel and the gear on the intermediate shaft is controlled within the range of 0.04-0.10mm.

[0010] This utility model has the following beneficial effects: 1. Effectively reduces gear knocking noise under zero torque conditions and vibration noise under low-speed, rough road conditions, improving driving quietness; by optimizing tooth flank clearance to reduce meshing impact, torque transmission is more stable and continuous, enhancing transmission smoothness. At the same time, reduced vibration can also extend the fatigue life of bearings and gears, thereby improving the overall service life.

[0011] 2. It can extend the grease retention time, reduce gear wear, improve lubrication performance, and reduce maintenance costs; and it does not rely on a complex and expensive active control system. All of the above-mentioned beneficial effects can be achieved with a simple structure, balancing performance improvement and cost control, and has good comprehensive benefits. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of a gear shaft system structure for an abnormal noise suppression structure in a motor drive assembly, as proposed in this utility model. Figure 2 This is a schematic diagram of the grease retention and damping system sealing structure of a noise suppression structure for a motor drive assembly proposed in this utility model; Figure 3 This is a schematic diagram of a bearing damping vibration reduction structure for suppressing abnormal noise in a motor drive assembly, as proposed in this utility model. Figure 4 This is a schematic diagram of the strut spacing of a noise suppression structure for a motor drive assembly proposed in this utility model; Figure 5 This is a schematic diagram of the tooth backlash of a noise suppression structure for a motor drive assembly proposed in this utility model. Figure 6 This invention proposes a noise suppression structure for a motor drive assembly. Figure 2 Enlarged view at point A.

[0013] Legend: 1. Input shaft; 2. Motor shaft; 3. Intermediate shaft; 4. Differential crown wheel; 5. Spline; 6. Sealing plug; 7. Rubber sealing ring; 8. Annular groove; 9. Rubber O-ring. Detailed Implementation

[0014] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0015] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are 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. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The utility model will be further described in detail below with reference to the accompanying drawings.

[0016] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances. Example

[0017] like Figures 1 to 6 As shown, this embodiment provides a noise suppression structure for a motor drive assembly, including an input shaft 1, one end of which is connected to a motor shaft 2, a gear on the input shaft 1 meshing with a gear on an intermediate shaft 3, and a gear on the intermediate shaft 3 meshing with a differential crown wheel 4.

[0018] Understandable, Figure 1 The diagram only schematically illustrates some of the components included in the noise suppression structure for the motor drive assembly. The actual shape, size, location, and construction of these components are not subject to change. Figure 1 Due to limitations, the noise suppression structure used in motor drive assemblies can also include, compared to... Figure 1 More or fewer parts.

[0019] It should also be understood that the grease, sealing plugs, rubber seals and rubber O-rings are all purchased commercially and are common knowledge in this field. They are only used and not modified, so the control method and circuit connection will not be described in detail.

[0020] Furthermore, in this embodiment, the input shaft 1 and the motor shaft 2 form a power input link, transmitting motor power to the intermediate shaft 3 via gear meshing, and then distributing power through the meshing of the intermediate shaft gear and the differential crown wheel 4. In this transmission chain, the meshing points of each gear are the main sources of abnormal noise, especially the impact during torque fluctuations or reversals, which easily trigger vibration noise. By optimizing the connection and meshing structure of each component, the vibration transmission and gear knocking during the transmission process are suppressed, thus solving the abnormal noise problem of the motor drive assembly under torque zero-crossing and low-speed, rough-circuit conditions.

[0021] Specifically, both the input shaft 1 and the motor shaft 2 are equipped with splines 5 inside, and high-performance grease is applied between the splines 5 on the input shaft 1 and the splines 5 inside the motor shaft 2.

[0022] In this embodiment, the spline 5 contact surfaces of the input shaft 1 and the motor shaft 2 are fully coated with high-performance grease. The base oil of the grease has a viscosity ≥150 cSt and a temperature resistance of -40~180℃. This reduces friction and wear in the spline fit and provides a damping effect through the viscosity of the grease, absorbing vibrations caused by torque fluctuations and reducing metal-to-metal contact noise. Full spline 5 coverage ensures uniform lubrication, and the wide temperature range adapts to different operating conditions. The damping effect and lubrication function of the grease work synergistically to reduce vibration and noise at the source.

[0023] Specifically, a sealing plug 6 is provided in the inner hole at the rear end of the input shaft 1, and a rubber sealing ring 7 is installed in the spline 5 at the front end of the input shaft 1.

[0024] As a preferred implementation, the sealing plug 6 in the inner hole at the rear end of the input shaft 1 is made of rubber with a hardness of 70±5 Shore A, forming a 0.3-0.5mm interference fit with the inner hole to prevent grease from being thrown out due to centrifugal force; the rubber sealing ring 7 in the front spline 5 is temperature resistant >180℃ and has a compression ratio of 18±2%, forming a double seal to prevent grease loss and isolate impurities. The double damping structure of the grease and the rubber sealing ring 7 extends the grease retention time, ensuring stable long-term damping effect, and simultaneously solving the problems of lubrication retention and vibration attenuation. Example

[0025] Specifically, the outer ring of the intermediate shaft 3 is provided with an annular groove 8, and a rubber O-ring 9 is provided inside the annular groove 8.

[0026] In this embodiment, a rubber O-ring 9 is installed in the annular groove 8 of the outer ring of the intermediate shaft 3, forming a ball bearing with an O-ring. The rubber O-ring 9 has a temperature resistance of -40~180℃ and forms an interference fit of 0.58-0.6mm with the bearing bore of the housing, providing radial elastic support for the bearing. The O-ring absorbs bearing vibration through its own deformation and blocks the transmission path of vibration to the housing, reducing resonance noise. The addition of a vibration damping structure to the outer ring of the bearing overcomes the limitations of traditional rigid supports, significantly attenuating vibration transmission through elastic buffering, especially effective for high-frequency vibration in low-speed, rough road conditions. Example

[0027] Specifically, the span of the differential crown wheel 4 is increased, and the parameters of the secondary gear are adjusted accordingly to reduce the meshing backlash.

[0028] This configuration increases the straddle distance of the differential crown wheel 4, while simultaneously adjusting the secondary gear parameters to actively reduce gear meshing backlash and achieve optimal backlash control. Precise straddle distance control ensures tighter gear meshing, reducing tooth surface impact clearance during torque reversal and fundamentally reducing gear knocking noise. The optimization of tooth backlash complements grease damping and O-ring vibration reduction, addressing the three sources of noise—meshing impact, vibration transmission, and frictional vibration—to achieve system-level noise reduction.

[0029] Specifically, the clearance between the differential crown wheel 4 and the gear on the intermediate shaft is controlled within the range of 0.04-0.10mm.

[0030] The clearance between the differential crown wheel 4 and the intermediate shaft gear is strictly controlled within the range of 0.04-0.10mm. This avoids abnormal noise caused by excessive clearance during reversing while maintaining an appropriate clearance to prevent thermal expansion and seizing. This range balances transmission accuracy and noise control, resulting in smoother and more continuous torque transmission. The optimized tooth flank clearance, combined with the composite damping system, significantly reduces gear knocking noise under zero torque conditions, while also reducing gear wear, extending the life of transmission components, and eliminating the need for complex electronic control, thus keeping costs under control.

[0031] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A noise suppression structure for a motor drive assembly, characterized in that: It includes an input shaft (1), one end of which is connected to a motor shaft (2), and the gear on the input shaft (1) meshes with the gear on the intermediate shaft (3), and the gear on the intermediate shaft (3) meshes with the differential crown wheel (4).

2. The noise suppression structure for a motor drive assembly according to claim 1, characterized in that: Both the input shaft (1) and the motor shaft (2) are provided with splines (5), and high-performance grease is applied between the splines (5) on the input shaft (1) and the splines (5) inside the motor shaft (2).

3. The noise suppression structure for a motor drive assembly according to claim 2, characterized in that: The input shaft (1) has a sealing plug (6) in the inner hole at the rear end, and a rubber sealing ring (7) is installed in the spline (5) at the front end of the input shaft (1).

4. The noise suppression structure for a motor drive assembly according to claim 1, characterized in that: The outer ring of the intermediate shaft (3) is provided with an annular groove (8), and a rubber O-ring (9) is provided in the annular groove (8).

5. The noise suppression structure for a motor drive assembly according to claim 1, characterized in that: The crossbar spacing of the differential crown wheel (4) is increased, and the secondary gear parameters are adjusted accordingly to reduce the meshing backlash.

6. The noise suppression structure for a motor drive assembly according to claim 5, characterized in that: The clearance between the differential crown wheel (4) and the gear on the intermediate shaft is controlled within the range of 0.04-0.10mm.

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