A motor assembly with reduced noise and vibration by balancing end plate of rotor

Abstract

The utility model discloses a motor assembly is reduced noise and vibration through rotor balance end plate belongs to motor technical field, including rotor balance end plate, the center is equipped with shaft hole, the key of the integral molding with fillet is equipped in the center of shaft hole, and rotor shaft penetrates the shaft hole, the end plate outer surface border line is equipped with the chamfer, and the inner surface is equipped with the groove and is matched with rotor iron core. The end plate adopts ADC12 die casting aluminum alloy magnetic isolation material integral molding, still collocates rotor shaft, sectional rotor iron core with magnetic steel, front and rear bearing, bearing pressboard, clamping spring and hexagon nut etc. constitute complete rotor assembly. The utility model discloses through the groove and strengthens the end plate strength, and lightens the weight, and the chamfer reduces the wind noise, and the symmetrical assembly optimizes the dynamic balance, can reduce motor noise 5 8dB, improves the bearing life 20 25%, is suitable for the vehicle -used permanent magnet synchronous motor, and the economy is high and simple to process.

Description

Technical Field

[0001] This utility model relates to the field of motor technology, specifically to a motor assembly that reduces noise and vibration through a rotor balance end plate. Background Technology

[0002] Permanent magnet synchronous motors are being used in a wider range of applications. With the development of electric vehicles, permanent magnet synchronous motors are being widely used as drive systems due to their advantages such as high efficiency and high power density.

[0003] Automotive motors are facing increasingly stringent requirements for stable performance, low noise, and adaptability to complex operating conditions. This necessitates the addition of balance end plates at both ends of the rotor core. These plates effectively prevent laminations from warping or spreading and also serve to isolate magnetic fields. Symmetrical installation of the two balance end plates enhances the crucial ability to improve balance.

[0004] In existing technologies, such as Figures 6 to 10 As shown, the balance end plate 26 mostly adopts the inner end face 23, which is the plane structure that is in contact with the iron core, and the outer end face 22 adopts the inner groove 24 structure. This structure is prone to deformation towards the outer end face 22. During the rotor rotation, the outer edge 25 is heavier and is prone to outward tension, deformation, increased wind noise, increased vibration, and reduced performance. Utility Model Content

[0005] This invention aims to solve the above-mentioned technical problems by providing a motor assembly that reduces noise and vibration through a rotor balance end plate.

[0006] To solve the above-mentioned technical problems, the technical solution provided by this utility model is as follows: A rotor balance end plate for reducing noise and vibration includes a rotor balance end plate made of ADC12 die-cast aluminum alloy magnetic shielding material, integrally formed by die-casting aluminum process, which has both magnetic shielding properties and structural strength.

[0007] Preferably, the rotor balance end plate has a shaft hole at its center, and a key is integrally formed at the center of the shaft hole. The key is used to achieve precise positioning of the rotor balance end plate and the rotor shaft and prevent them from rotating relative to each other. Both sides of the key are provided with rounded corners, which can effectively disperse stress concentration at the key opening and improve the structural strength of the connection between the key and the rotor balance end plate. The rotor shaft can pass through the shaft hole to achieve assembly.

[0008] Preferably, the outer surface edge of the rotor balance end plate is chamfered. The chamfer can change the flow direction of the radial ventilation airflow inside the motor, reduce the impact of the airflow on the edge of the end plate, and thus reduce radial ventilation noise. The inner surface of the rotor balance end plate, that is, the side that is in contact with the rotor core, is provided with grooves. The grooves are distributed in a ring array. On the one hand, this can enhance the structural rigidity of the rotor balance end plate and prevent it from deforming during high-speed rotation. On the other hand, it can reduce the amount of end plate material used and reduce the weight of the end plate.

[0009] Preferably, the rotor assembly further includes a rotor shaft, a rotor core with magnets, a front bearing, a rear bearing, a bearing pressure plate, and a retaining ring. The rotor core with magnets is divided into segmented rotor core A, segmented rotor core B, segmented rotor core C, and segmented rotor core D, with each segmented core sequentially mounted on the rotor shaft. The rotor balance end plate is assembled at both ends of the rotor core, and the plane of the rotor core is horizontally fitted with the inner surface of the rotor balance end plate to ensure the coaxiality of the assembled rotor structure. The front bearing and the rear bearing are respectively mounted at both ends of the rotor shaft, forming the support end of the rotor and guiding the rotor to rotate smoothly. The bearing pressure plate is fixed to the motor end cover by bolts to limit the outer rings of the front and rear bearings. The retaining ring is fitted into the groove of the rotor shaft to limit the inner rings of the front and rear bearings. Through the cooperation of the bearing pressure plate and the retaining ring, the axial positioning and fixation of the rotor are achieved. A hexagonal nut is also threaded to the end of the rotor shaft, which can lock the rotor balance end plate located at the end of the rotor core to prevent the end plate from loosening during operation.

[0010] Preferably, the motor assembly further includes a front end cover and a rear end cover. The front end cover is provided with a front bearing steel sleeve, and the front bearing is embedded in the front bearing steel sleeve to form the fixed end of the rotor. The rear end cover is provided with a rear bearing steel sleeve, and the rear bearing is embedded in the rear bearing steel sleeve to form the floating end of the rotor. This can compensate for the thermal expansion and contraction of the rotor during operation and ensure the concentricity of the rotor.

[0011] With the above structure, this utility model has the following advantages: Improved structural strength: The grooves on the inner surface of the rotor balance end plate significantly enhance the structural rigidity of the end plate. Combined with the high strength characteristics of ADC12 die-cast aluminum alloy, this effectively prevents deformation of the end plate during high-speed rotation, ensuring the stability of the rotor structure. Testing shows that the deformation resistance of the end plate of this invention is more than 30% higher than that of existing end plates.

[0012] Noise reduction: The chamfer on the outer surface can change the direction of radial ventilation airflow and reduce airflow impact noise. According to actual working condition tests, the motor operating noise is reduced by 5-8dB compared with the motor using the existing end plate, which meets the low noise requirements of automotive motors.

[0013] Cost-effectiveness: This utility model achieves performance optimization simply by adding grooves and chamfers to the end plate structure, without the need for additional complex processing steps, and the processing technology is simple; at the same time, the grooves reduce the amount of material used and lower the material cost, and the overall manufacturing cost is basically the same as that of existing end plates, making it highly economical.

[0014] Dynamic balance optimization and lifespan extension: The rotor balance end plate structure is flat and thinner. Combined with the weight reduction design of the groove, the rotor rotational inertia is effectively reduced, and the dynamic balance adjustment is reduced by more than 40% compared with the existing structure. The improved rotor dynamic balance stability not only reduces motor vibration, but also reduces bearing wear. According to calculations, the bearing life can be extended by 20%-25%, while reducing rotor losses and improving motor operating efficiency by 2%-3%.

[0015] The above overview is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features of the present invention will become readily apparent from the accompanying drawings and the following detailed description. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a first structural schematic diagram of the rotor balance end plate of this utility model; Figure 2 This is a schematic diagram of the second structure of the rotor balance end plate of this utility model; Figure 3 This is a cross-sectional view of the rotor balance end plate of this utility model; Figure 4 This is a cross-sectional view and a partially enlarged view of the present invention; Figure 5 This is a schematic diagram of the structure of this utility model; Figure 6 This is a schematic diagram of the first structure of the rotor balance end plate in the prior art; Figure 7 This is a schematic diagram of the second structure of the rotor balance end plate in the prior art; Figure 8 This is a cross-sectional view of the rotor balance end plate of existing technology; Figure 9 This is a cross-sectional view of the prior art; Figure 10 This is a schematic diagram of the existing technology.

[0018] As shown in the figure: 1. Rotor balance end plate; 2. Key; 3. Fillet; 4. Chamfer; 5. Groove; 6. Outer surface; 7. Inner surface; 8. Shaft; 9. Snap ring; 10. Front bearing; 11. Bearing pressure plate; 12. Hexagonal nut; 13. Rear bearing; 14. Segmented rotor core A; 15. Segmented rotor core B; 16. Segmented rotor core C; 17. Segmented rotor core D; 18. Front bearing steel sleeve; 19. Rear bearing steel sleeve; 20. Front end cover; 21. Rear end cover; 22. Outer end face; 23. Inner end face; 24. Inner groove; 25. Outer edge; 26. Balance end plate. Detailed Implementation

[0019] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0020] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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 application according to the specific circumstances.

[0021] The present invention will now be described in further detail in conjunction with the full text.

[0022] Combined with appendix Figures 1-5 A motor assembly for reducing noise and vibration through a rotor balance end plate includes a rotor balance end plate 1. The rotor balance end plate 1 has a shaft hole at its center, a key 2 at its center, and rounded corners 3 on both sides of the key. The key is integrally formed with the rotor balance end plate 1, and a rotor shaft 8 passes through it. The outer surface 6 of the rotor balance end plate 1 has chamfered edges 4, and the inner surface 7 has a shallow groove 5 structure that mates with the surface of the rotor core.

[0023] In specific implementation of this utility model, such as Figure 4 and Figure 5As shown, the rotor has a rotor shaft 8 and a rotor core with magnets. The support end consists of a front bearing 10 and a rear bearing 13, which guide the rotor to rotate smoothly. The bearing outer ring is limited by a bearing pressure plate 11, and the inner ring is limited by a snap ring 9, which provides axial positioning and fixation. At both ends of the rotor core, rotor balance end plates 1 are installed to increase end strength. The outer surface 6 of the rotor balance end plate 1 has a chamfered edge 4 structure to reduce radial ventilation noise. The inner surface 7 has a groove 5 structure to increase the strength of the rotor balance end plate 1 and prevent deformation.

[0024] The groove 5 has an annular structure. It also includes a rotor shaft 8, a rotor core with magnets, a front bearing 10, a rear bearing 13, a bearing pressure plate 11, and a retaining ring 9; the rotor core is sleeved on the rotor shaft 8, and the rotor shaft 8 passes through the shaft hole; the rotor balance end plate 1 is assembled at both ends of the rotor core; the front bearing 10 and the rear bearing 13 are respectively sleeved at both ends of the rotor shaft 8, the bearing pressure plate 11 limits the outer ring of the front bearing 10, and the retaining ring 9 limits the inner ring of the front bearing 10.

[0025] Rotor balance end plate structure description: 1. The novel rotor balance end plate structure of this utility model is made of die-cast aluminum using a die-cast aluminum manufacturing process, and the material selected is ADC12 die-cast aluminum alloy magnetic shielding material.

[0026] 2. The novel rotor balance end plate structure of this utility model includes a rotor balance end plate 1. The rotor balance end plate 1 has a shaft hole at its center, and a key 2 is provided at the center of the shaft hole for positioning the rotor balance end plate. The key has rounded corners 3 on both sides to increase the strength of the key opening. It is integrally formed with the rotor balance end plate 1, and the rotor shaft 8 passes through it.

[0027] 3. The outer surface 6 of the rotor balance end plate 1 has a chamfered edge 4 structure to reduce radial ventilation noise. The inner surface 7 has a groove 5 structure to increase the strength of the rotor balance end plate 1, prevent deformation, and reduce material consumption and processing costs.

[0028] 4. Working principle or operating steps: Press the rotor balance end plate 1 onto the rotor shaft 8, then press the segmented rotor core A14 with magnets onto the rotor shaft 8, ensuring that the plane of the rotor core is horizontally aligned with the plane of the rotor balance end plate. In sequence, press the segmented rotor core B15, rotor core C16, and rotor core D17 with magnets onto the rotor shaft 8, then press the rotor balance end plate 1 onto the rotor shaft 8. Finally, screw the hexagonal nut 12 onto the rotor shaft 8 to lock the rotor balance end plate, thus completing the assembly.

[0029] 5. Work process description: The rotor's fixed end is a front bearing 10, installed inside the front end cover 20, which has a front bearing steel sleeve 18. The floating end is a rear bearing 13, installed inside the rear end cover 21, which has a rear bearing steel sleeve 19. During motor operation, the rotor is supported by the front and rear bearings to ensure concentric rotation. Noise generated during operation, caused by air compression inside the motor or air rubbing against the motor's fixed components, is primarily caused by the radial ventilation grooves. This noise increases as the gap between the rotating and fixed components decreases.

[0030] In a specific implementation of this invention, the outer surface 6 of the rotor balance end plate is provided with a chamfer 4. By changing the direction of radial ventilation through the chamfer 4, wind noise can be reduced, thereby reducing motor noise, ensuring the symmetry of both ends of the rotor, and reducing the vibration generated by the motor.

[0031] In a specific implementation of this utility model, the inner surface 7 of the rotor balance end plate is provided with a groove 5. The groove 5 can strengthen the structural strength of the rotor balance end plate 1 when the rotor rotates at high speed, prevent deformation, and at the same time reduce the weight of the end plate, effectively reducing the rotor weight and moment of inertia, and the dynamic balance adjustment amount is small.

[0032] Assembly process of this utility model: Step 1: Press a rotor balance end plate 1 onto one end of the rotor shaft 8, ensuring that the inner surface 7 of the end plate faces the rotor core assembly direction; Step 2: Press the segmented rotor core A14 with magnets into the rotor shaft 8 so that the end face of the segmented rotor core A14 is in horizontal contact with the inner surface 7 of the rotor balance end plate 1. Step 3: Press the segmented rotor core B15, segmented rotor core C16, and segmented rotor core D17 into the rotor shaft 8 in sequence to ensure that the segmented cores fit tightly together and the coaxiality error is controlled within 0.05mm. Step 4: Press the other rotor balance end plate 1 onto the other end of the rotor shaft 8 so that the inner surface 7 of the end plate is horizontally attached to the end face of the segmented rotor core D17. Step 5: Screw the hexagonal nut 12 into the end thread of the rotor shaft 8, and tighten it with a torque wrench to the specified torque of 25-30 N·m to fix the rotor balance end plate 1; Step 6: Press the front bearing 10 and the rear bearing 13 onto both ends of the rotor shaft 8 respectively, and install the retaining ring 9 in the retaining groove of the rotor shaft 8 to limit the inner ring of the bearing; Step 7: Press the front bearing steel sleeve 18 onto the front end cover 20 and the rear bearing steel sleeve 19 onto the rear end cover 21. Then, install the assembled rotor assembly into the front end cover 20 and the rear end cover 21, so that the front bearing 10 is embedded in the front bearing steel sleeve 18 and the rear bearing 13 is embedded in the rear bearing steel sleeve 19. Step 8: Install the bearing pressure plate 11 and fix it to the front cover 20 and the rear cover 21 with bolts to limit the outer ring of the bearing and complete the motor assembly.

[0033] Work process: After the motor starts, the rotor achieves high-speed rotation with the support of the front bearing 10 and the rear bearing 13. The cooperation between the front bearing 10 and the front bearing steel sleeve 18, and the rear end cover 21 and the rear bearing steel sleeve 19 ensures the concentricity of the rotor operation.

[0034] During operation, the air inside the motor flows radially due to the rotation of the rotor. The chamfer 4 on the outer surface 6 of the rotor balance end plate 1 changes the airflow path, preventing the airflow from directly impacting the edge of the end plate and reducing wind noise. At the same time, the groove 5 on the inner surface 7 enhances the structural strength of the end plate, preventing the end plate from deforming due to the centrifugal force generated by high-speed rotation, ensuring the dynamic balance stability of the rotor, and reducing vibration.

[0035] In addition, the close fit between the segmented rotor core and the rotor balance end plate 1 effectively prevents the laminations from warping or spreading out, and the magnetic shielding material reduces magnetic field leakage, further improving the motor's operating efficiency and reliability.

[0036] The present invention and its embodiments have been described above. This description is not restrictive, and the embodiments shown throughout the text are only one of the embodiments of the present invention. The actual structure is not limited to this. In conclusion, if a person skilled in the art is inspired by this description and designs a similar structure and embodiment without departing from the inventive spirit of the present invention, such design should fall within the protection scope of the present invention.

Claims

1. A motor assembly that reduces noise and vibration through a rotor balance end plate, characterized in that, The rotor balance end plate (1) has a shaft hole in the center, and a key (2) is integrally formed in the center of the shaft hole. Both sides of the key (2) are provided with rounded corners (3). The outer surface (6) of the rotor balance end plate (1) has chamfers (4). The inner surface (7) of the rotor balance end plate (1) has grooves (5), and the inner surface (7) is in contact with the surface of the rotor core.

2. The motor assembly for reducing noise and vibration through a rotor balance end plate according to claim 1, characterized in that: The rotor balance end plate (1) is made of ADC12 die-cast aluminum alloy magnetic shielding material and is integrally formed by die-casting aluminum manufacturing process.

3. The motor assembly for reducing noise and vibration through a rotor balance end plate according to claim 1, characterized in that: It also includes a rotor shaft (8), a rotor core with magnets, a front bearing (10), a rear bearing (13), a bearing pressure plate (11), and a snap ring (9); the rotor core is sleeved on the rotor shaft (8), and the rotor shaft (8) passes through the shaft hole; the rotor balance end plate (1) is assembled at both ends of the rotor core; the front bearing (10) and the rear bearing (13) are respectively sleeved at both ends of the rotor shaft (8), the bearing pressure plate (11) limits the outer ring of the front bearing (10), and the snap ring (9) limits the inner ring of the front bearing (10).

4. The motor assembly for reducing noise and vibration through a rotor balance end plate according to claim 3, characterized in that: The rotor core includes segmented rotor core A (14), segmented rotor core B (15), segmented rotor core C (16) and segmented rotor core D (17). The segmented rotor core A (14), segmented rotor core B (15), segmented rotor core C (16) and segmented rotor core D (17) are sequentially sleeved on the rotor shaft (8) and located between the two rotor balance end plates (1).

5. The motor assembly for reducing noise and vibration through a rotor balance end plate according to claim 4, characterized in that: The rotor shaft (8) is threaded with a hexagonal nut (12) at its end.

6. The motor assembly for reducing noise and vibration through a rotor balance end plate according to claim 3, characterized in that: It also includes a front cover (20) and a rear cover (21). The front cover (20) is provided with a front bearing steel sleeve (18), and the front bearing (10) is embedded in the front bearing steel sleeve (18). The rear cover (21) is provided with a rear bearing steel sleeve (19), and the rear bearing (13) is embedded in the rear bearing steel sleeve (19).

7. The motor assembly for reducing noise and vibration through a rotor balance end plate according to claim 1, characterized in that: The groove (5) has a ring structure.

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