A motor with a noise reduction isolation cabin structure

Abstract

The utility model discloses a kind of motor with noise reduction isolation cabin structure, including motor casing and noise reduction end cover;Noise reduction end cover has circular body, and central point is located on motor rotor axis;The front end surface of circular body is formed with the concave arc surface of whole back;Observe from arbitrary radius angle, the arc surface is multi-section arc surface design, and it is formed by the arc line of multiple different curvatures of tail-to-tail joint combination, forms composite arc surface structure;The front end surface of circular body is protruding with several first partitions, and each first partition is evenly distributed with center point as reference point radially equiangular, the region of arc surface is separated into several independent cavities;Through the multi-cavity structure formed by the composite arc surface structure on noise reduction end cover and multiple first partitions, noise reduction isolation cabin structure is jointly constituted.This utility model adopts arc surface and multi-cavity design to form noise reduction isolation cabin in structural design, can effectively reduce motor noise, while structure realizes low difficulty, and can significantly enhance the overall structure strength, and comprehensive cost advantage is obvious.

Description

Technical Field

[0001] This utility model relates to the field of motors for new energy vehicles, specifically to a motor with a noise reduction and isolation chamber structure. Background Technology

[0002] In recent years, the rapid development of China's automobile industry has not only improved people's quality of life and efficiency but also promoted the progress of social productivity. With increasingly fierce market competition, consumers' demands for vehicle performance are constantly rising. During long-distance driving, vehicle noise pollution has become a significant problem affecting comfort. Therefore, how to improve the in-vehicle acoustic environment through noise reduction technologies such as vibration damping and sound insulation has become an urgent issue for the industry to address.

[0003] As a core component of the drive system in new energy vehicles, the drive motor, while consuming electrical energy to provide power, is also one of the main sources of vehicle noise, making noise reduction optimization particularly crucial. Unlike traditional gasoline vehicles, electric vehicles prioritize quietness in their design; however, the absence of engine noise amplifies other noise sources—such as bearing noise, mechanical vibrations caused by rotor imbalance, or electromagnetic noise caused by magnetic field harmonics. These high-frequency components are more easily detected by the human ear, thus requiring effective suppression of noise transmission paths through methods such as optimized motor structure design. Utility Model Content

[0004] The purpose of this invention is to provide a motor with a noise reduction and isolation chamber structure.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] An electric motor with a noise reduction isolation chamber structure includes a motor housing and a noise reduction end cap assembled at the rear end of the motor housing;

[0007] The noise reduction end cover has a circular body, the center of which is located on the axis of the motor rotor; the front end of the circular body is provided corresponding to the cavity of the motor housing and forms an integrally concave arc surface; the area where the arc surface is located is between the bearing chamber in the middle of the circular body and the sealing assembly surface on the periphery.

[0008] Viewed from any radius, the arc surface is a multi-segment arc surface design, which is composed of multiple sets of arcs with different curvatures connected end to end to form a composite arc surface structure;

[0009] The front end face of the circular body is provided with several first partitions, and each of the first partitions is radially distributed at equal angles with the center point as a reference, dividing the area where the arc surface is located into several independent cavities.

[0010] The noise reduction isolation chamber structure is formed by the composite arc surface structure on the noise reduction end cap and the multi-cavity structure formed by multiple first partitions.

[0011] In the above scheme, the curved surface disperses sound wave energy in multiple directions through diffusion reflection and scattering, reducing the intensity of reflection in a single direction, effectively reducing echo and standing wave effects, and making the noise distribution more uniform. The multi-segment curved surface design avoids the problem of a single arc concentrating sound waves at a single point, causing local noise amplification. The composite curved surface structure promotes both the diffusion and reflection of sound waves and ensures a uniform sound field distribution. Compared to a single curved surface that may back-focus sound waves, this composite structure solves the problem of local noise enhancement at its source.

[0012] In the above scheme, increasing the number of partitions can lengthen the reflection path of sound waves within the cavity, increase the number of reflections, and make the sound energy distribution more uniform. At the same time, more partitions will form more independent cavities, enhance structural rigidity, effectively suppress resonance phenomena, thereby reducing echo and standing wave interference, and significantly improving the uniformity of the sound field and sound quality performance.

[0013] A further technical solution is that, viewed from any radius angle of the circular body, the number of arcs is 2 to 5 segments.

[0014] In a further technical solution, each of the arcs is a circular arc, and the center of the circle is located on the front side of the front end face.

[0015] In a further technical solution, the first partition has an evenly distributed angle of 22.5°~30° and a quantity of 12~16.

[0016] A further technical solution involves a second partition protruding from the front end face of the circular body, with the second partition arranged concentrically around the center point; each of the second partitions and each of the first partitions together form the multi-cavity structure. Increasing the concentric circle design allows for the formation of more isolation cavities, significantly altering the resonant frequency, and simultaneously improving stiffness.

[0017] In a further technical solution, the second partition is provided in one or two layers. When there are two layers, the second partitions in each layer are arranged in concentric circles and at equal intervals.

[0018] In a further technical solution, the ratio of the height H2 of the first partition and the second partition to the depth H1 of the front end face of the circular body is (1 / 2~3 / 4):1.

[0019] A further technical solution also includes a resolver cover plate, which is fitted onto the rear end face of the noise reduction end cap;

[0020] It also includes a rubber pad, which is at least located at the contact surface of the rear end face of the resolver cover and the noise reduction end cover; the position and size of the rubber pad are configured to enclose the sound propagation path and face the cavity of the motor housing. With this design, the rubber pad facing the cavity can achieve a better sound attenuation effect.

[0021] In the above scheme, the material of the rubber pad is easily deformed when the sound wave propagates, which consumes energy and leads to faster sound attenuation and good vibration isolation effect. The high damping characteristics accelerate the sound attenuation, and the elasticity and structural design achieve sound insulation and sound absorption.

[0022] In a further technical solution, the rubber pad is also provided at the mating surface between the motor junction box cover and the junction box.

[0023] A further technical solution is that the rubber pad is a silicone rubber pad with a thickness of 5±1mm. Silicone rubber pads have high elasticity, low hardness, and high damping characteristics. The core influence of silicone rubber on sound propagation lies in low-speed propagation and high energy attenuation. At the same time, since the internal temperature of the cavity is high when the motor is working, the use of silicone rubber can have a longer aging resistance life and replacement cycle.

[0024] The terms "first," "second," etc., used in this article do not specifically refer to order or sequence, nor are they intended to limit this case; they are merely used to distinguish components or operations described using the same technical terms.

[0025] The terms "connection" or "positioning" as used in this article can refer to two or more components or devices making direct physical contact with each other, or making indirect physical contact with each other, or to two or more components or devices operating or moving with each other.

[0026] The terms “include,” “including,” and “have” used in this article are all open-ended, meaning they include but are not limited to.

[0027] Unless otherwise specified, the terms used herein generally have their ordinary meaning in the context of the art, the subject matter, and the specific context. Certain terms used to describe this case will be discussed below or elsewhere in this specification to provide additional guidance to those skilled in the art in describing the case.

[0028] The terms “front,” “back,” “up,” “down,” “left,” and “right” used in this article are directional terms. In this case, they are only used to describe the positional relationship between the structures and are not intended to limit the specific direction of the protection scheme or its actual implementation.

[0029] The working principle and advantages of this utility model are as follows:

[0030] This invention analyzes the motor structure and noise sources: the motor drive end transmits power via a flange end cover and splined shaft connected to the gearbox; the non-drive end integrates the winding output terminal (powered by the high-voltage harness) and the resolver (monitoring rotor speed / position). To balance three-phase output and resolver protection, a large cavity is formed between the winding, the rear end cover, and the resolver cover, causing cavity resonance noise.

[0031] In view of this, this utility model proposes the core technology of a noise reduction isolation chamber. Specifically, this utility model innovatively integrates the rear end cover and the rotary cover plate into a noise reduction isolation chamber, suppressing noise through the following synergistic mechanism:

[0032] 1. Sound wave energy dissipation

[0033] On the one hand, the sound waves are diffused and reflected through the composite arc surface multi-curvature structure; on the other hand, the sound wave path is extended and scattering is increased by forming multiple cavities through partitions. With this design, the local sound pressure peak can be reduced and the echo and standing wave can be reduced.

[0034] 2. Broadband Resonance Suppression

[0035] On the one hand, the overall stiffness is improved by the partition, thereby suppressing low-frequency structural resonance; on the other hand, the irregular curved surface of the arc destroys the coherence of high-frequency standing waves.

[0036] 3. Optimization of the dual path of source and propagation

[0037] On the one hand, the composite arc surface blocks the convergence of sound waves (eliminates sound focusing), and on the other hand, the multi-cavity formed by the partition disperses or cancels the resonance peak, increases the number of sound wave reflections, and dissipates energy through friction, heat conduction, etc. At the same time, the composite arc surface affects the sound wave reflection path. The acoustic characteristics produce complex effects through the coupling of "resonance-reflection-diffusion". With this design, the synergistic noise reduction effect of "blocking + diversion" can be achieved.

[0038] 4. Actual test results

[0039] This invention utilizes a composite arc surface structure and a first partition (and a second partition) to form a multi-cavity collaborative design, which allows mid-to-high frequency electromagnetic whistling to be diffused and attenuated by the arc surface, and low-frequency structural resonance to be suppressed by the stiffness of the partition. This improves the uniformity of noise distribution by more than 25%, avoiding the defects of uneven frequency band suppression in traditional solutions.

[0040] In summary, traditional solutions rely on extreme optimization of vehicle sound insulation materials or motor electromagnetic systems to meet high NVH standards. While these methods can improve vibration and electromagnetic noise, the application of new materials and the increased design complexity significantly increase development costs. In contrast, this invention's composite arc surface structure and partitions form a multi-cavity isolation chamber design, supplemented by noise reduction design with rubber pads. This reduces implementation difficulty while enhancing the overall structural strength, making it particularly suitable for harsh environments and complex road conditions, and offering a more cost-effective overall solution. Attached Figure Description

[0041] Appendix Figure 1 This is a schematic diagram of the structure of an embodiment of the present utility model;

[0042] Appendix Figure 2 for Figure 1 A schematic diagram of the AA-direction cross-section;

[0043] Appendix Figure 3 This is a schematic diagram of the front end of an embodiment of the present utility model;

[0044] Appendix Figure 4 for Figure 3 Schematic diagram of the BB-direction cross section;

[0045] Appendix Figure 5 This is a schematic diagram of the back end of an embodiment of the present utility model;

[0046] Appendix Figure 6 This is a perspective view of the noise-reducing end cap according to an embodiment of the present utility model;

[0047] Appendix Figure 7 This is a schematic diagram of the front end of the noise-reducing end cap according to an embodiment of the present invention;

[0048] Appendix Figure 8 for Figure 7 A schematic diagram of the CC-direction cross-section;

[0049] Appendix Figure 9 This is a schematic diagram of the front side of the spinner cover plate according to an embodiment of the present utility model;

[0050] Appendix Figure 10 for Figure 9 Schematic diagram of the DD-direction cross section;

[0051] Appendix Figure 11 for Figure 9 Schematic diagram of the EE section;

[0052] Appendix Figure 12 This is a schematic diagram of the structure of the rubber pad in an embodiment of the present invention;

[0053] Appendix Figure 13 for Figure 12 A schematic diagram of the FF section.

[0054] In the attached diagrams: 1. Motor housing; 11. Cavity; 2. Noise-reducing end cover; 21. Circular body; 22. Center point; 23. Arc surface; 231. Arc line; 24. Bearing chamber; 25. Sealing assembly surface; 26. First partition; 27. Cavity; 28. Second partition; 3. Axis; 4. Resolver cover; 41. Third partition; 5. Rubber gasket; 6. Junction box cover; 7. Junction box. Detailed Implementation

[0055] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0056] Example: The present invention will be clearly described below with illustrations and detailed description. Any person skilled in the art who understands the examples of the present invention can make changes and modifications based on the technology taught in the present invention without departing from the spirit and scope of the present invention.

[0057] The terminology used herein is for the purpose of describing specific embodiments only and is not intended to limit the scope of this work. Singular forms such as “a,” “this,” “this,” “the,” and “the” as used herein also include plural forms.

[0058] See appendix Figures 1-8 As shown, a motor with a noise reduction and isolation chamber structure includes a motor housing 1 and a noise reduction end cover 2 assembled at the rear end of the motor housing 1.

[0059] The noise reduction end cover 2 has a circular body 21, the center point 22 of which is located on the axis 3 of the motor rotor; the front end of the circular body 21 is disposed corresponding to the cavity 11 of the motor housing 1 and forms an integrally concave arc surface 23; the area where the arc surface 23 is located is between the bearing chamber 24 in the middle of the circular body 21 and the sealing assembly surface 25 on the periphery, and is arranged in a ring shape (see Figure 7 (The ring-shaped area selected by two dashed lines).

[0060] Viewed from any radius, the arc surface 23 is a multi-segment arc surface design, which is composed of multiple sets of arcs 231 with different curvatures connected end to end to form a composite arc surface structure.

[0061] The front end surface of the circular body 21 is provided with several first partitions 26, and each of the first partitions 26 is radially distributed at equal angles with the center point 22 as a reference, dividing the area where the arc surface 23 is located into several independent cavities 27.

[0062] The noise reduction isolation chamber structure is formed by the composite arc surface structure on the noise reduction end cap 2 and the multi-cavity structure formed by multiple first partitions 26.

[0063] Preferably, when viewed from any radius angle of the circular body 21, the number of arcs 23 is 2 to 5 segments.

[0064] Preferably, each of the arcs 23 is a circular arc, and the center of the arc is located on the front side of the front end face, that is, in the cavity 11 of the motor housing 1.

[0065] Preferably, the first partition 26 has an even distribution angle of 22.5°~30° and a quantity of 12~16.

[0066] Preferably, a second partition 28 is also provided on the front end surface of the circular body 21, and the second partition 28 is arranged in a concentric circle with the center point 22 as a reference.

[0067] Preferably, in this embodiment, the second partition 28 has one layer. In other embodiments, when two layers are provided, the second partitions 28 in each layer are arranged in concentric circles and at equal intervals. The second partition 28, together with the first partition 26, forms a multi-cavity structure.

[0068] Preferred, such as Figure 8 As shown, the ratio of the height H2 of the first partition 26 and the second partition 28 to the depth H1 of the front end face of the circular body 21 is 0.5:1.

[0069] Preferred, such as Figures 9-11 As shown, it also includes a resolver cover plate 4, which is fitted onto the rear end face of the noise reduction end cover 2. The resolver cover plate 4 has a crisscrossing third partition 41 protruding from one side surface facing the noise reduction end cover 2. While satisfying the requirement of strengthening the structural strength, it also plays an auxiliary role in noise reduction through the formation of a multi-cavity structure.

[0070] like Figure 12 , Figure 13 As shown, it also includes a rubber pad 5, which is at least disposed at the contact surface of the rear end face of the resolver cover plate 4 and the noise reduction end cover 2; the position and size of the rubber pad 5 are configured to enclose the sound propagation path and face the cavity 11 of the motor housing 1.

[0071] Preferably, the rubber pad 5 is also disposed at the mating surface between the motor junction box cover 6 and the junction box 7.

[0072] Preferably, the rubber pad 5 is a silicone rubber pad with a thickness of 5±1mm.

[0073] Table 1. Noise test data of motor at different speeds

[0074]

[0075] The noise test results in Table 1 are explained below:

[0076] Test environment: NVH silent laboratory.

[0077] Test instruments: LMS noise and vibration analysis system and GRAS 46AE.

[0078] Test conditions: The motor is placed on the tray in a free state and run under no-load conditions. Audio is captured using a GRAS 46AE. A hemispherical test surface with a test radius of 1m is used, with five test points positioned at the front, back, left, and right of the motor, and above the center of the motor. The height of the four test points is 0.25m, and the height of the upper test point is 1m above the reflector. At this point, the test surface area S = 2πr 2 =6.28m 2 .

[0079] The steady-state noise decibel values ​​of the motor were measured at speeds of 3000rpm, 600rpm, and 9000rpm, and the average value of the five measurement points was taken as the final motor noise value.

[0080] In Table 1, the “arc + partition” of the embodiment is a noise reduction isolation cabin structure scheme that simultaneously sets up a composite arc surface structure and a multi-cavity structure; compared with the embodiment, Comparative Example 1 does not have a composite arc surface structure and a multi-cavity structure design; compared with the embodiment, Comparative Example 2 only has a composite arc surface structure; compared with the embodiment, Comparative Example 3 only has a multi-cavity structure.

[0081] As shown in Table 1, the noise levels of motors with composite arc surface structures and multi-cavity structures are good, according to the comparison of noise tests with different structural designs. The noise level of motors with arc surface designs but no isolation chamber structure is the second best, which is 5-6 dB higher. The noise level of motors with isolation chamber designs but no arc surface structure is close to the second type, with an increase of about 2 dB. However, the noise level of motors without any design measures is the worst, which is about 15 dB higher than the motors with dual measures.

[0082] This invention analyzes the motor structure and noise sources—the motor drive end transmits power via a flange end cover and splined shaft connected to the gearbox; the non-drive end integrates the winding output terminal (powered by the high-voltage harness) and the rotary transformer (monitoring rotor speed / position). To balance three-phase output and resolver protection, a large cavity is formed between the winding, the rear end cover, and the resolver cover, causing cavity resonance noise. This invention utilizes a composite arc surface structure and a partition to form a multi-cavity isolation chamber design, supplemented by a rubber pad noise reduction design, employing the following synergistic mechanisms to suppress noise: Sound wave energy dissipation: The composite arc surface multi-curvature structure diffuses and reflects sound waves; the partition forms multiple cavities, extending the sound wave path and increasing scattering, reducing local sound pressure peaks and echoes and standing waves; Broadband resonance suppression: The partition increases overall rigidity, thereby suppressing low-frequency structural resonance; the irregular curved surface of the arc surface disrupts the coherence of high-frequency standing waves; Source-propagation dual-path optimization: The composite arc surface blocks sound wave convergence (eliminating sound focusing), and the multiple cavities formed by the partition dissipate propagation energy, achieving a synergistic noise reduction effect of "blocking + diversion". In addition, the structure of this utility model is less difficult to implement than traditional solutions, and while reducing the implementation difficulty, it enhances the overall structural strength, making it particularly suitable for harsh environments and complex road conditions, and has a more advantageous overall cost.

[0083] The above embodiments are only for illustrating the technical concept and features of this utility model, and are intended to enable those skilled in the art to understand the content of this utility model and implement it accordingly. They should not be construed as limiting the scope of protection of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be included within the scope of protection of this utility model.

Claims

1. A motor with a noise reduction and isolation chamber structure, characterized in that: Includes a motor housing and a noise-reducing end cap mounted on the rear end of the motor housing; The noise reduction end cover has a circular body, the center of which is located on the axis of the motor rotor; the front end of the circular body is provided corresponding to the cavity of the motor housing and forms an integrally concave arc surface; the area where the arc surface is located is between the bearing chamber in the middle of the circular body and the sealing assembly surface on the periphery. Viewed from any radius, the arc surface is a multi-segment arc surface design, which is composed of multiple sets of arcs with different curvatures connected end to end to form a composite arc surface structure; The front end face of the circular body is provided with several first partitions, and each of the first partitions is radially distributed at equal angles with the center point as a reference, dividing the area where the arc surface is located into several independent cavities. The noise reduction isolation chamber structure is formed by the composite arc surface structure on the noise reduction end cap and the multi-cavity structure formed by multiple first partitions.

2. The motor with a noise reduction isolation chamber structure according to claim 1, characterized in that: Viewed from any radius angle of the circular body, the number of arcs is 2 to 5 segments.

3. The motor with a noise reduction isolation chamber structure according to claim 1, characterized in that: Each of the aforementioned arcs is a circular arc, and the center of each arc is located on the front side of the front end face.

4. The motor with a noise reduction isolation chamber structure according to claim 1, characterized in that: The first partition has an evenly distributed angle of 22.5° to 30° and a quantity of 12 to 16.

5. A motor with a noise reduction and isolation chamber structure according to claim 1, characterized in that: The front end face of the circular body is also provided with a second partition, and the second partition is arranged in a concentric circle with the center point as the reference; each of the second partitions and each of the first partitions together form the multi-cavity structure.

6. A motor with a noise reduction and isolation chamber structure according to claim 5, characterized in that: The second partition is provided in one or two layers. When there are two layers, the second partitions in each layer are arranged in concentric circles and at equal intervals.

7. A motor with a noise reduction isolation chamber structure according to claim 5, characterized in that: The ratio of the height H2 of the first partition and the second partition to the depth H1 of the front end face of the circular body is (1 / 2~3 / 4):

1.

8. A motor with a noise reduction isolation chamber structure according to claim 1, characterized in that: It also includes a resolver cover plate, which is fitted onto the rear end face of the noise reduction end cap; It also includes a rubber pad, which is at least located at the contact surface of the rear end face of the resolver cover and the noise reduction end cover; the position and size of the rubber pad are configured to enclose the sound propagation path and face the cavity of the motor housing.

9. A motor with a noise reduction isolation chamber structure according to claim 8, characterized in that: The rubber pad is also provided at the mating surface between the motor junction box cover and the junction box.

10. A motor with a noise reduction isolation chamber structure according to claim 8 or 9, characterized in that: The rubber pad is a silicone rubber pad with a thickness of 5±1mm.

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