Noise-reducing gears, electric drive systems and vehicles

Abstract

This application relates to the field of gear technology, specifically disclosing a noise-reducing gear, an electric drive system, and a vehicle. The noise-reducing gear includes a shoulder located in the middle, a gear ring surrounding the shoulder, and a web connecting the shoulder and the gear ring. Along the axial direction of the noise-reducing gear, the size of the gear ring is the tooth width, and the size of the shoulder is the shoulder width. The tooth width is smaller than the shoulder width, and the gear ring is offset to one side relative to the shoulder. There is an offset between the gear ring and the shoulder, and the ratio of the offset to the tooth width is between 0 and 0.4. Along the axial direction, the gear ring has a first center line perpendicular to the tooth width, and the shoulder has a second center line perpendicular to the shoulder width. The offset is the distance between the first center line and the second center line. By offsetting the gear ring to one side relative to the shoulder, quantifying the degree of offset, and controlling the offset to within 0.4 times the tooth width, the stiffness and modal frequency of the noise-reducing gear are improved, thereby improving or avoiding resonance and improving the NVH performance of the vehicle.

Description

Technical Field

[0001] This utility model relates to the field of gear technology, specifically to a noise-reducing gear, an electric drive system, and a vehicle. Background Technology

[0002] The electric drive system of a vehicle is characterized by high speed and wide speed range, and its gears are subjected to wide-band excitation during operation. This excitation mainly originates from the electromagnetic excitation of the motor and the meshing excitation of the gears. As the core transmission component of the reducer in the electric drive system, the modal frequencies of the gears are crucial to the NVH (Noise, Vibration, and Harshness) performance and reliability of the reducer and even the entire vehicle.

[0003] However, most electric drive systems currently used in vehicles suffer from problems such as insufficient gear modal frequencies leading to resonance. Utility Model Content

[0004] This application provides a noise-reducing gear, an electric drive system, and a vehicle. The noise-reducing gear can increase the modal frequency, improve or avoid resonance phenomena, and improve the NVH performance of the vehicle.

[0005] To solve the above-mentioned technical problems, one technical solution adopted in this application is: to provide a noise-reducing gear, which includes a shoulder located in the middle, a gear ring surrounding the shoulder, and a web connecting the shoulder and the gear ring; along the axial direction of the noise-reducing gear, the size of the gear ring is the tooth width, the size of the shoulder is the shoulder width, the tooth width is smaller than the shoulder width, and the gear ring is offset to one side relative to the shoulder; wherein, there is an offset between the gear ring and the shoulder, and the ratio of the offset to the tooth width is between 0 and 0.4; along the axial direction, the gear ring has a first center line perpendicular to the tooth width, and the shoulder has a second center line perpendicular to the shoulder width; the offset is the distance between the first center line and the second center line.

[0006] The web includes a plate and a first protrusion protruding from one side of the plate along its axial direction. The surface of the first protrusion opposite to the plate is an inclined surface. The thickness of the first protrusion gradually decreases along its axial direction from the shoulder to the toothed ring.

[0007] The width of the first protrusion gradually decreases in the circumferential direction from the shoulder to the gear ring.

[0008] The web also includes a second protrusion protruding from the other side of the plate along the axial direction, and the surface of the second protrusion opposite to the plate is a plane.

[0009] The first protrusion has multiple protrusions that are evenly spaced along the circumference, and the second protrusion corresponds to the first protrusion one by one.

[0010] The plate also has weight-reducing holes, which are located between two adjacent first protrusions.

[0011] The thickness of the plate in the axial direction remains constant from the shoulder to the gear ring, and the ratio between the thickness of the plate and the tooth width is between 0.4 and 1.

[0012] The shoulder has an axial through hole at its center, and the inner wall of the axial through hole has an internal spline.

[0013] This application also includes a second technical solution, providing an electric drive system including the aforementioned noise-reducing gear.

[0014] This application also includes a third technical solution, providing a vehicle that includes the above-described electric drive system.

[0015] The beneficial effects of this application are as follows: Unlike existing technologies, the noise-reducing gear, electric drive system, and vehicle provided in this application include a shoulder located in the middle, a gear ring surrounding the shoulder, and a web connecting the shoulder and the gear ring. Along the axial direction of the noise-reducing gear, the size of the gear ring is the tooth width, and the size of the shoulder is the shoulder width. The tooth width is smaller than the shoulder width, and the gear ring is offset to one side relative to the shoulder. There is an offset between the gear ring and the shoulder, and the ratio of the offset to the tooth width is between 0 and 0.4. Along the axial direction, the gear ring has a first center line perpendicular to the tooth width, and the shoulder has a second center line perpendicular to the shoulder width. The offset is the distance between the first center line and the second center line. By offsetting the gear ring to one side relative to the shoulder, quantifying the degree of offset, and controlling the offset to within 0.4 times the tooth width, the stiffness and modal frequency of the noise-reducing gear are improved, thereby improving or avoiding resonance phenomena and improving the NVH performance of the vehicle. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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, wherein:

[0017] Figure 1 This is a schematic diagram of the structure of one embodiment of the noise reduction gear of this application;

[0018] Figure 2 yes Figure 1 A schematic diagram of the structure on the other side of the axial direction of the noise reduction gear;

[0019] Figure 3 yes Figure 1 A schematic diagram of the cross-section of the noise-reducing gear AA;

[0020] Figure 4 yes Figure 1 A schematic diagram of the cross-section of the noise reduction gear BB.

[0021] Reference numerals: 1. Shoulder; 11. Axial through hole; 12. Internal spline; 2. Gear ring; 3. Web plate; 31. First protrusion; 32. Second protrusion; 33. Plate body; 34. Weight reduction hole; 100. Noise reduction gear. Detailed Implementation

[0022] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, it should be noted that, for ease of description, only the parts relevant to this application are shown in the accompanying drawings, not the entire structure. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application.

[0023] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0024] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features.

[0025] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" 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, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between 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.

[0026] Please refer to the reference. Figure 1 and Figure 3 , Figure 1 This is a schematic diagram of the structure of an embodiment of the noise reduction gear provided in this application. Figure 3 yes Figure 1A schematic diagram of the cross-section of a noise-reducing gear AA. One aspect of this application provides a noise-reducing gear 100, which includes a shoulder 1 located in the middle, a gear ring 2 surrounding the shoulder 1, and a web 3 connecting the shoulder 1 and the gear ring 2. Along the axial direction of the noise-reducing gear 100, the gear ring 2 has a tooth width B, and the shoulder 1 has a shoulder width D. The tooth width B is smaller than the shoulder width D, and the gear ring 2 is offset to one side relative to the shoulder 1. The gear ring 2 and the shoulder 1 have an offset amount a, and the ratio of the offset amount a to the tooth width B is between 0 and 0.4, for example, 0.1, 0.2, 0.3, 0.4, etc. Figure 3 As shown, along the axial direction, the gear ring 2 has a first center line L1 perpendicular to the tooth width B, and the shoulder 1 has a second center line L2 perpendicular to the shoulder width D; the offset amount a is the distance between the first center line L1 and the second center line L2. By offsetting the gear ring 2 relative to the shoulder 1 on one side, quantifying the degree of offset and controlling the offset amount a within 0.4 times the tooth width B, the stiffness and modal frequency of the noise reduction gear 100 are improved, thereby improving or avoiding resonance phenomena and improving the NVH performance of the vehicle.

[0027] Specifically, the noise-reducing gear 100 in this embodiment may include a large intermediate shaft gear in an electric drive system. A novel spoke structure is formed by offsetting the gear ring 2 relative to the shoulder 1 and controlling the offset a within 0.4 times the tooth width B. By controlling the tooth width B to be smaller than the shoulder width D, the noise-reducing gear 100 in this embodiment can reduce the offset a and improve or avoid axial stress concentration. It should be noted that the axial dimension of the gear ring 2 is called the tooth width B, and the axial dimension of the shoulder 1 is called the shoulder width D. When the noise-reducing gear 100 in this embodiment is subjected to axial stress, since the offset a of the gear ring 2 relative to the shoulder 1 is within 0.4 times the tooth width B, the support stiffness on the shoulder 1 side is significantly improved, and the risk of bending deformation at the gear ring 2 can be reduced. Furthermore, the axial section of the gear ring 2 has a straight line perpendicular to the tooth width B as a first center line L1, and the axial section of the shoulder 1 has a straight line perpendicular to the shoulder width D as a second center line L2. By adjusting the relative position of the gear ring 2 and the shoulder 1, the first center line L1 and the second center line L2 can be kept parallel but offset by a distance, i.e., an offset amount 'a'. This structural design can accurately represent the degree of offset of the gear ring 2 relative to the shoulder 1, providing a basis for subsequent structural optimization, quantifying and controlling the size of the offset amount 'a'.

[0028] Furthermore, by establishing a quantitative index for the centerline offset between the gear ring 2 and the shoulder 1, the degree of offset of the gear ring 2 relative to the shoulder 1 can be precisely controlled, thereby optimizing the axial stiffness distribution of the noise reduction gear 100. Precise control of the offset a also enables the noise reduction gear 100 to increase its modal frequency under spatial constraints, moving it away from the excitation frequency range, thereby suppressing resonance, reducing noise and vibration levels, and improving the NVH performance of the electric drive system and even the vehicle.

[0029] During use, the noise-reducing gear 100 of this application will inevitably be subjected to excitation from electromagnetic excitation of the motor and gear meshing excitation. By controlling the offset a between the gear ring 2 and the shoulder 1 to be within 0.4 times the tooth width B, the support stiffness and modal frequency of the noise-reducing gear 100 are improved, thereby avoiding the frequency band of electromagnetic excitation or meshing excitation of the motor, reducing the risk of resonance, and improving the NVH performance of the vehicle.

[0030] Furthermore, the gear ring 2 can adopt a helical tooth design. The helical tooth design, combined with the offset of the gear ring 2, can improve the uniformity of stress distribution in the meshing area, reduce the peak value of tooth surface contact stress, and thus improve the stability of the structure.

[0031] Please continue to refer to the reference. Figure 4 , Figure 4 yes Figure 1 A structural schematic diagram of the cross-section of the noise reduction gear BB. In one embodiment of this application, the web plate 3 includes a plate body 33 and a first protrusion 31 protruding from one side of the plate body 33 along the axial direction. The surface of the first protrusion 31 opposite to the plate body 33 is an inclined surface. The thickness of the first protrusion 31 gradually decreases along the axial direction from the shoulder 1 to the gear ring 2.

[0032] Specifically, such as Figure 3 and Figure 4 As shown, the contact surface between the first protrusion 31 and the plate 33 is a sloped structure, and its axial thickness gradually decreases along the direction from the shoulder 1 to the gear ring 2. Through the sloped structure design and the gradual thickness design of the first protrusion 31, the axial load can achieve continuous stress distribution in the direction from the shoulder 1 to the gear ring 2, which can eliminate stress concentration and improve the modal frequency.

[0033] Furthermore, since shoulder 1 is the rigid fixed end connecting the gear to other structural components and bears the maximum bending moment stress, the first protrusion 31 at shoulder 1 has the greatest thickness to enhance its bending resistance. The root of gear ring 2 is the flexible load end with a more uniform stress distribution. Therefore, the first protrusion 31 at the root of gear ring 2 has the smallest thickness, which can improve or avoid stress abrupt changes and also reduce mass, achieving structural lightweighting.

[0034] In one specific embodiment, to improve the continuity and uniformity of stress concentration elimination in the first protrusion 31 and to ensure smooth load transfer, the inclined surface of the first protrusion 31 can be designed as a plane, meaning the thickness of the first protrusion 31 changes linearly. Furthermore, a linear profile facilitates forging, reducing costs and increasing efficiency. In another specific embodiment, the inclined surface of the first protrusion 31 can also adopt other shapes, such as stepped or curved surfaces.

[0035] In one embodiment of this application, as Figure 1 As shown, the width of the first protrusion 31 in the circumferential direction gradually decreases from the shoulder 1 to the toothed ring 2.

[0036] Specifically, the first protrusion 31 features a gradually decreasing width in the circumferential direction, with its width gradually decreasing from the shoulder 1 towards the gear ring 2. This gradually decreasing width structure optimizes stress distribution, improves stiffness in high bending moment regions (shoulder 1 side), and reduces or avoids weight increase due to material redundancy in low bending moment regions (gear ring 2 side). The continuous cross-sectional change eliminates stress concentration, improves load transfer smoothness, and enhances the overall structural fatigue strength. This design, while increasing strength, reduces material consumption and, by matching the mechanical properties of the axial force direction, increases the modal frequency, thereby suppressing resonance noise and improving the NVH performance of the electric drive system and even the vehicle.

[0037] In one specific embodiment, the circumferential width of the first protrusion 31 can also vary linearly. A linear profile can facilitate forging and improve the uniformity of stress distribution. Of course, in another specific embodiment, the circumferential width of the first protrusion 31 can also be designed as a non-linear gradual shape according to the stress characteristics, for example, retaining a wider cross-section in the critical stress area while gradually shrinking in other areas.

[0038] Please continue to combine Figure 2 , Figure 2 yes Figure 1 A schematic diagram of the structure on the other side of the noise reduction gear along the axial direction. In one embodiment of this application, the web further includes a second protrusion protruding from the other side of the plate body along the axial direction, and the surface of the second protrusion opposite to the plate body is a plane.

[0039] Specifically, such as Figure 2 As shown, the contact surface between the second protrusion 32 and the plate 33 is a planar structure, meaning that the axial thickness of the second protrusion 32 remains constant. The planar structure design of the second protrusion 32 can provide stable axial support, improving or avoiding stiffness imbalance caused by structural asymmetry.

[0040] During use, the noise-reducing gear 100 of this application will inevitably be subjected to axial load stress. Through the gradual thickness design of the first protrusion 31 along the axial direction from the shoulder 1 to the gear ring 2, on the one hand, the stiffness distribution of the noise-reducing gear 100 can be optimized, making it map to the axial load direction F, thereby increasing the gear's natural frequency; on the other hand, it can also achieve smooth attenuation of bending moment stress, avoiding fatigue fracture caused by stress concentration. It should be noted that in this embodiment, the axial load direction F on the noise-reducing gear 100 is from the first protrusion 31 towards the second protrusion 32, such as... Figure 4 As shown, the inclined surface of the first protrusion 31 can correspond one-to-one with the load and stress and form a mapping relationship; in order to improve stiffness, the gear ring 2 can be designed to be offset relative to the shoulder 1 towards the second protrusion 32.

[0041] In one embodiment of this application, combined with Figure 1 and Figure 2 As shown, the first protrusion 31 has multiple protrusions that are evenly spaced along the circumference, and the second protrusion 32 corresponds one-to-one with the first protrusion 31.

[0042] Specifically, both the first protrusion 31 and the second protrusion 32 are circumferentially distributed, with the same number and equal spacing. This structural design, with corresponding protrusion numbers and uniform circumferential distribution, effectively matches the stiffness distribution with the axial load direction F, thereby improving the uniformity of the stress transmission path, mitigating or preventing excessive stress concentration in local areas, and enhancing the overall deformation resistance of the noise-reducing gear 100. The second protrusion 32 corresponds one-to-one with the first protrusion 31, forming multi-point support in the axial direction, enhancing the bending moment resistance of the noise-reducing gear 100, and increasing the modal frequency. Furthermore, it reduces the vibration energy generated by uneven stiffness during meshing of the noise-reducing gear 100, lowering the noise level and extending its service life.

[0043] In one embodiment of this application, the plate 33 is further provided with a weight reduction hole 34, which is located between two adjacent first protrusions 31.

[0044] Specifically, by setting weight-reducing holes 34 between adjacent first protrusions 31, the overall weight of the noise-reducing gear 100 can be reduced while maintaining structural rigidity, thereby increasing the modal frequency and improving the vehicle's NVH performance. Since the first protrusions 31 protrude from the plate 33, a pit will be formed between two adjacent first protrusions 31. Multiple pits together form a pit array. The weight-reducing holes 34 are arranged in the circumferential pit array, which improves or avoids the stress concentration problem caused by local material loss, so that the structure still has sufficient fatigue strength after weight reduction. In addition, the cross-sectional shape of the weight-reducing holes 34 can be circular, rectangular, or a closed shape enclosed by continuous curves, and its shape and size can be flexibly adjusted according to actual working conditions.

[0045] Furthermore, the spatial topological relationship formed by the first protrusion 31, the plate 33, the shoulder 1, and other structures ensures that the setting of the weight reduction hole 34 will not disrupt the overall force balance. On the contrary, the dynamic performance of the structure can be improved through the reasonable distribution of materials.

[0046] In one embodiment of this application, as Figure 3 As shown, the thickness T of the plate 33 in the axial direction remains constant from the shoulder 1 to the gear ring 2, and the ratio between the thickness T of the plate 33 and the tooth width B is between 0.4 and 1, for example, 0.4, 0.6, 0.8, 1, etc.

[0047] Specifically, the thickness T of the plate 33 in the axial direction remains constant, meaning that the plate 33 can achieve efficient torque transmission through equal thickness shear resistance, and the ratio of the thickness T to the tooth width B is limited to the range of 0.4 to 1, which can improve the strength of the plate 33.

[0048] In one embodiment of this application, the center of the shoulder 1 is provided with an axial through hole 11, and the inner wall of the axial through hole 11 is provided with an inner spline 12.

[0049] Specifically, the axial through hole 11 at the center of the shoulder 1 is used to accommodate connecting components, and the internal spline 12 on the inner wall of the through hole forms a detachable transmission connection with the shaft-like parts. By providing the axial through hole 11 in the shoulder 1 and cooperating with the internal spline 12 structure, a stable connection between the noise-reducing gear 100 and the transmission shaft can be achieved while reducing the structural weight. The tooth meshing characteristics of the internal spline 12 can disperse stress concentration and improve the rigidity of the transmission system. The design of the axial through hole 11 reduces the weight of the shoulder 1 while ensuring structural strength, and with the optimization of axial stiffness, the overall modal frequency can be improved.

[0050] In another aspect, this application also provides an electric drive system that includes the noise-reducing gear 100 described above. Specifically, since the electric drive system includes the noise-reducing gear 100 described in the above embodiments, it also has the beneficial effects of the noise-reducing gear 100, which will not be repeated here.

[0051] In another aspect, this application also provides a vehicle that includes the aforementioned electric drive system. Specifically, since the vehicle includes the electric drive system described in the above embodiments, it also possesses the beneficial effects of the aforementioned electric drive system, which will not be elaborated further here.

[0052] It should be noted that the terms "horizontal" and "vertical" do not imply that the components must be absolutely horizontal or vertical, but rather that they can be slightly tilted. Similarly, the terms "parallel" and "perpendicular" do not imply that the components are absolutely parallel or perpendicular, but rather that they can have a certain angular deviation. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but rather that it can be slightly tilted. In addition, the orientations or positional relationships indicated by terms such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise" are based on the orientations or positional relationships shown in the accompanying drawings, or the orientations or positional relationships that are commonly used when the product of this application is in use. They are only for the purpose of describing the embodiments of this application 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. Therefore, they should not be construed as limitations on this application.

[0053] It is understood that the term "multiple" in this document means at least two, such as two, three, etc., unless otherwise specified. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices. The term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects are in an "or" relationship.

[0054] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A noise-reducing gear, characterized in that, The noise reduction gear includes a shoulder (1) located in the middle, a gear ring (2) surrounding the shoulder (1), and a web plate (3) connecting the shoulder (1) and the gear ring (2). Along the axial direction of the noise-reducing gear, the size of the gear ring (2) is the tooth width, the size of the shoulder (1) is the shoulder width, the tooth width is smaller than the shoulder width, and the gear ring (2) is offset to one side relative to the shoulder (1); wherein, there is an offset between the gear ring (2) and the shoulder (1), and the ratio of the offset to the tooth width is between 0 and 0.4; wherein, Along the axial direction, the gear ring (2) is provided with a first center line perpendicular to the tooth width, and the shoulder (1) is provided with a second center line perpendicular to the shoulder width; The offset amount is the distance between the first center line and the second center line.

2. The noise-reducing gear according to claim 1, characterized in that, The web (3) includes a plate (33) and a first protrusion (31) protruding from one side of the plate (33) along its axial direction. The surface of the first protrusion (31) opposite to the plate (33) is an inclined surface. The thickness of the first protrusion (31) along the axial direction gradually decreases from the shoulder (1) to the toothed ring (2).

3. The noise-reducing gear according to claim 2, characterized in that, The width of the first protrusion (31) in the circumferential direction gradually decreases from the shoulder (1) to the toothed ring (2).

4. The noise-reducing gear according to claim 2, characterized in that, The web (3) also includes a second protrusion (32) protruding from the other side of the plate (33) along the axial direction, and the surface of the second protrusion (32) opposite to the plate (33) is a plane.

5. The noise-reducing gear according to claim 4, characterized in that, The first bump (31) has multiple bumps that are evenly spaced along the circumference, and the second bump (32) corresponds to the first bump (31) one by one.

6. The noise-reducing gear according to claim 2, characterized in that, The plate (33) is also provided with a weight reduction hole (34), which is located between two adjacent first protrusions (31).

7. The noise-reducing gear according to claim 6, characterized in that, The thickness of the plate (33) in the axial direction remains constant from the shoulder (1) to the toothed ring (2), and the ratio between the thickness of the plate (33) and the tooth width is between 0.4 and 1.

8. The noise-reducing gear according to claim 1, characterized in that, The shoulder (1) has an axial through hole (11) at its center, and the inner wall of the axial through hole (11) has an inner spline (12).

9. An electric drive system, characterized in that, include: The noise-reducing gear according to any one of claims 1-8.

10. A vehicle, characterized in that, include: The electric drive system as claimed in claim 9.

Images