Drive shaft assembly and vehicle

Abstract

The application discloses a driving shaft assembly and a vehicle, and relates to the technical field of vehicle manufacturing. The driving shaft assembly comprises a driving shaft, a plurality of first spline parts arranged on the driving shaft, and a plurality of second spline parts arranged on the end of the driving shaft; a hub bearing, a plurality of first spline matching parts arranged in the hub bearing, and a plurality of second spline matching parts arranged on the end of the hub bearing; wherein the plurality of first spline parts and the plurality of first spline matching parts are engaged one by one to form a radial spline pair, and the plurality of second spline parts and the plurality of second spline matching parts are engaged one by one to form an axial spline pair. The driving shaft assembly of the embodiment can be radially positioned through the radial spline pair, so that the engagement precision requirement and the assembly difficulty of the axial spline pair are reduced, the possibility that the axial spline pair is caused to fail due to the top tooth is reduced, the torque can be transmitted through the radial spline pair and the axial spline pair, the torque bearing capacity of the driving shaft assembly is improved, and the service life of the driving shaft assembly is prolonged.

Description

Technical Field

[0001] This invention relates to the field of vehicle manufacturing technology, and more particularly to a drive shaft assembly and a vehicle having the drive shaft assembly. Background Technology

[0002] Currently, torque transmission between the drive shaft and wheel bearing in passenger vehicles mainly adopts two connection methods: internal spline connection and end face spline connection. Internal spline connection relies on the radial meshing of the external spline of the drive shaft and the internal spline of the wheel bearing to transmit torque and provide radial positioning. End face spline connection relies on the axial meshing of the spline teeth on the end face of the drive shaft and the end face of the wheel bearing to transmit torque, which requires a large axial preload.

[0003] However, single internal spline connections suffer from stress concentration on the spline tooth surface, limited resistance to overload and impact, and extremely high requirements for machining and assembly alignment. They are also prone to wear or plastic deformation when transmitting continuously increasing dynamic torque. On the other hand, single end face spline connections rely heavily on axial preload, and preload decay can lead to connection loosening. They also lack radial positioning function, require additional structures, and have weak resistance to separation. Any of the above single connection methods faces challenges in terms of reliability, durability, and torque load capacity when encountering conditions such as the significant increase in torque brought about by new energy vehicles, and there is room for improvement. Summary of the Invention

[0004] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes a drive shaft assembly that can be radially positioned by a radial spline pair, thereby reducing the meshing accuracy requirements and assembly difficulty of the axial spline pair, reducing the possibility of failure of the axial spline pair due to tooth breakage, and improving the torque carrying capacity of the drive shaft assembly by jointly transmitting torque through the radial and axial spline pairs, thus extending the service life of the drive shaft assembly.

[0005] According to an embodiment of the present invention, a drive shaft assembly includes: a drive shaft having a plurality of first spline portions arranged sequentially along the circumference outside the drive shaft, and a plurality of second spline portions arranged sequentially along the circumference at the end of the drive shaft; a hub bearing having a plurality of first spline mating portions arranged sequentially along the circumference inside the hub bearing, and a plurality of second spline mating portions arranged sequentially along the circumference at the end of the hub bearing; wherein at least a portion of the drive shaft passes through the hub bearing, and the plurality of first spline portions and the plurality of first spline mating portions are engaged one-to-one to form radial spline pairs to enable circumferential transmission between the hub bearing and the drive shaft, and the plurality of second spline portions and the plurality of second spline mating portions are engaged one-to-one to form axial spline pairs to enable circumferential transmission between the hub bearing and the drive shaft.

[0006] According to embodiments of the present invention, the drive shaft assembly forms a radial spline pair by engaging multiple first spline portions and multiple first spline mating portions in a one-to-one correspondence to perform circumferential transmission between the drive shaft and the hub bearing. It also forms an axial spline pair by engaging multiple second spline portions and multiple second spline mating portions in a one-to-one correspondence to perform circumferential transmission between the drive shaft and the hub bearing. Radial positioning can be achieved through the radial spline pair, thereby reducing the meshing accuracy requirements and assembly difficulty of the axial spline pair, reducing the possibility of failure due to tooth breakage, and enhancing the torque carrying capacity of the drive shaft assembly by jointly transmitting torque through both the radial and axial spline pairs, thus extending the service life of the drive shaft assembly.

[0007] According to some embodiments of the present invention, the drive shaft assembly includes a shaft body and a first connecting shaft connected axially. The shaft body has a first connecting end face formed at one end near the first connecting shaft. At least a portion of the first connecting shaft is adapted to extend into the hub bearing so that the first connecting end face abuts against the end of the hub bearing. The first spline portion is disposed on the outer peripheral wall of the first connecting shaft, and the second spline portion is disposed on the first connecting end face.

[0008] According to some embodiments of the present invention, the drive shaft assembly includes a hub bearing comprising an inner bearing ring, rolling elements, and an outer bearing ring arranged radially from the inside to the outside. The inner bearing ring is provided with a first spline mating portion, and a second connecting end face is formed at the end of the inner bearing ring. The second spline mating portion is disposed on the second connecting end face.

[0009] According to some embodiments of the present invention, the drive shaft assembly further includes a second connecting shaft connected to one end of the first connecting shaft away from the shaft body. The second connecting shaft is used to connect with a connector after the first connecting shaft extends into the inner ring of the bearing so that the hub bearing and the drive shaft are pre-tightened axially.

[0010] According to some embodiments of the present invention, in a drive shaft assembly, the second connecting shaft is provided with a threaded portion, the connecting member is constructed as a connecting nut, and a threaded mating portion is formed inside the connecting nut, the threaded mating portion being threadedly engaged with the threaded portion.

[0011] According to some embodiments of the present invention, in a drive shaft assembly, the outer diameter of the first connecting shaft is greater than the outer diameter of the second connecting shaft and less than the minimum outer diameter of the shaft body.

[0012] According to some embodiments of the present invention, the drive shaft assembly has an outer chamfer on its outer side and an inner chamfer on its inner side. The outer chamfer matches the inner chamfer, and the outer chamfer and the inner chamfer are used to guide the drive shaft and the hub bearing to align and engage.

[0013] According to some embodiments of the present invention, in the drive shaft assembly, the outer chamfer is provided at the end of the first connecting shaft, and the inner chamfer is provided on the side of the first spline mating portion near the second connecting end face.

[0014] According to some embodiments of the present invention, in the drive shaft assembly, the first spline portion is constructed as a radial external spline, the first spline mating portion is constructed as an internal spline groove, the radial external spline meshes with the internal spline groove, and the radial external spline is constructed as an involute tooth shape; the second spline portion is constructed as a face spline, the second spline mating portion is constructed as a face spline groove, and the face spline meshes with the face spline groove.

[0015] The present invention also proposes a vehicle.

[0016] The vehicle according to embodiments of the present invention includes the drive shaft assembly described in any of the above embodiments.

[0017] The vehicle and the aforementioned drive shaft assembly have the same advantages over the prior art, which will not be elaborated here.

[0018] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0019] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the structure of the drive shaft according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a hub bearing according to an embodiment of the present invention; Figure 3 This is a cross-sectional view of a drive shaft assembly according to an embodiment of the present invention; Figure 4 This is an exploded view of a drive shaft assembly according to an embodiment of the present invention.

[0020] Figure label: Drive shaft assembly 100, Drive shaft 1, first spline portion 11, second spline portion 12, shaft body 13, first connecting end face 131, first connecting shaft 14, second connecting shaft 15, threaded portion 151, external chamfer 16. Hub bearing 2, first spline mating part 21, second spline mating part 22, bearing inner ring 23, second connecting end face 231, bearing outer ring 24, inner chamfer 25. 3. Radial spline pair, 4. Axial spline pair, 5. Connecting piece. Detailed Implementation

[0021] Embodiments of the present invention are described in detail below. Examples of these 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 the present invention, and should not be construed as limiting the present invention.

[0022] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention 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 the invention. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means three or more.

[0023] In the description of this invention, it should be noted that, unless otherwise explicitly 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 or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of three components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0024] Unless otherwise specified, the front-back direction in this application refers to the longitudinal direction of the vehicle, i.e., the X direction; the left-right direction refers to the lateral direction of the vehicle, i.e., the Y direction; and the up-down direction refers to the vertical direction of the vehicle, i.e., the Z direction.

[0025] The following is for reference. Figures 1-4 The drive shaft assembly 100 described in this embodiment of the invention can be radially positioned by the radial spline pair 3, thereby reducing the meshing accuracy requirements and assembly difficulty of the axial spline pair 4, reducing the possibility of failure of the axial spline pair 4 due to the top teeth, and the torque can be transmitted by the radial spline pair 3 and the axial spline pair 4 together, thereby improving the torque carrying capacity of the drive shaft assembly 100 and helping to extend the service life of the drive shaft assembly 100.

[0026] like Figures 1-4 As shown, a drive shaft assembly 100 according to an embodiment of the present invention includes: a drive shaft 1 and a hub bearing 2.

[0027] The drive shaft 1 has a plurality of first spline portions 11 arranged sequentially along the circumference on its exterior, and a plurality of second spline portions 12 arranged sequentially along the circumference on its end. The hub bearing 2 has a plurality of first spline mating portions 21 arranged sequentially along the circumference on its interior, and a plurality of second spline mating portions 22 arranged sequentially along the circumference on its end. At least a portion of the drive shaft 1 passes through the hub bearing 2, and the plurality of first spline portions 11 and the plurality of first spline mating portions 21 mesh one-to-one to form radial spline pairs 3 so that the hub bearing 2 and the drive shaft 1 can perform circumferential transmission. The plurality of second spline portions 12 and the plurality of second spline mating portions 22 mesh one-to-one to form axial spline pairs 4 so that the hub bearing 2 and the drive shaft 1 can perform circumferential transmission.

[0028] Specifically, the drive shaft assembly 100 is typically connected between the differential and the wheel for transmitting torque, load transfer, and precise positioning. The drive shaft assembly 100 includes a drive shaft 1 and a wheel bearing 2. The drive shaft 1 is connected to the differential, and the wheel bearing 2 is connected to the wheel via a steering knuckle. Thus, the drive shaft assembly 100 can be connected to the differential and the vehicle respectively through the drive shaft 1 and the wheel bearing 2. At least a portion of the drive shaft 1 passes through the wheel bearing 2, meaning that part or all of the drive shaft 1 can extend into the interior of the wheel bearing 2, allowing the drive shaft 1 to be poweredly connected to the wheel bearing 2. In other words, power can be transmitted between the drive shaft 1 and the wheel bearing 2, thereby enabling power transmission between the differential and the wheel through the drive shaft assembly 100.

[0029] The drive shaft 1 can transmit the rotational force output by the differential to the wheel hub bearing 2. The wheel hub bearing 2 then transmits the rotational force to the wheel through the steering knuckle, so that the wheel rotates. The radial and axial loads of the wheel can be transmitted in the opposite direction to the steering knuckle and suspension through the wheel hub bearing 2, so as to avoid the wheel hub bearing 2 from breaking, the suspension from deforming and running off course. At least a part of the drive shaft 1 extends into the wheel hub bearing 2, so that the drive shaft 1 can be located in the center of the wheel hub bearing 2, so as to ensure that the rotation axis of the drive shaft 1 is aligned with the wheel axis, avoid the drive shaft 1 from wobble, and thus avoid vibration and abnormal noise.

[0030] The drive shaft 1 has a first spline portion 11 on its outer peripheral wall, and the hub bearing 2 has a first spline mating portion 21 on its inner peripheral wall. The first spline portion 11 can engage with the first spline mating portion 21, meaning that one of the first spline portion 11 and the first spline mating portion 21 is constructed as a spline and the other as a spline groove. When at least a portion of the drive shaft 1 is extended into the hub bearing 2, the first spline portion 11 can engage with the first spline mating portion 21 radially. Thus, the engagement of the first spline portion 11 and the first spline mating portion 21 enables the power connection between the drive shaft 1 and the hub bearing 2, allowing circumferential transmission between the drive shaft 1 and the hub bearing 2 through the first spline portion 11 and the first spline mating portion 21.

[0031] Furthermore, there are multiple first spline portions 11 and multiple first spline mating portions 21, meaning that the number of first spline portions 11 and first spline mating portions 21 can be two, three, or more. By sequentially distributing multiple first spline portions 11 along the circumference of the drive shaft 1, the multiple first spline portions 11 can be neatly arranged along the circumference of the drive shaft 1. Similarly, by sequentially distributing multiple first spline mating portions 21 along the circumference of the hub bearing 2, the multiple first spline mating portions 21 can be neatly arranged along the circumference of the hub bearing 2. Thus, when at least a portion of the drive shaft 1 is extended into the hub bearing 2, the multiple first spline portions 11 and the multiple first spline mating portions 21 can mesh one-to-one to form a radial spline pair 3.

[0032] This ensures that the number of first spline portions 11 and first spline mating portions 21 are equal. That is, for each first spline portion 11, there is a corresponding first spline mating portion 21 that can mesh with it. Thus, when at least a part of the drive shaft 1 is extended into the hub bearing 2, each first spline portion 11 can press against the corresponding first spline mating portion 21 so that the hub bearing 2 and the drive shaft 1 can perform circumferential transmission. In this way, the radial spline pair 3 can be used to radially position and transmit torque between the drive shaft 1 and the hub bearing 2.

[0033] Meanwhile, the drive shaft 1 has a second spline portion 12 at one end, and the hub bearing 2 has a second spline mating portion 22 at one end. The second spline portion 21 can engage with the second spline mating portion 22, so that one of the second spline portion 12 and the second spline mating portion 22 is constructed as a spline and the other is constructed as a spline groove. When at least a part of the drive shaft 1 is extended into the hub bearing 2 and the end of the drive shaft 1 is in abutting contact with the end of the hub bearing 2, the second spline portion 12 can engage with the second spline mating portion 22 axially. Thus, the drive shaft 1 and the hub bearing 2 can be connected by power through the engagement of the second spline portion 12 and the second spline mating portion 22, and circumferential transmission can be performed between the drive shaft 1 and the hub bearing 2 through the second spline portion 12 and the second spline mating portion 22.

[0034] Furthermore, there are multiple second spline portions 12 and multiple second spline mating portions 22. That is, the number of second spline portions 12 and multiple second spline mating portions 22 can be two, three or more. By distributing multiple second spline portions 12 sequentially along the circumference of the drive shaft 1 at the end of the drive shaft 1, the multiple second spline portions 12 can be neatly arranged along the circumference of the drive shaft 1 at the end of the drive shaft 1. Similarly, by distributing multiple second spline mating portions 22 sequentially along the circumference of the hub bearing 2 at the end of the hub bearing 2, the multiple second spline mating portions 22 can be neatly arranged along the circumference of the hub bearing 2 at the end of the hub bearing 2. Thus, when at least a portion of the drive shaft 1 is extended into the hub bearing 2 and the end of the drive shaft 1 is in abutting contact with the end of the hub bearing 2, the multiple second spline portions 12 and the multiple second spline mating portions 22 can mesh one-to-one to form an axial spline pair 4.

[0035] This ensures that the number of second spline portions 12 and second spline mating portions 22 are equal. That is, for each second spline portion 12, there is a corresponding second spline mating portion 22 that can mesh with it. Thus, when at least a portion of the drive shaft 1 is extended into the hub bearing 2 and the end of the drive shaft 1 is in abutting contact with the end of the hub bearing 2, each second spline portion 12 can be in abutting contact with the corresponding second spline mating portion 22 so that the hub bearing 2 and the drive shaft 1 can perform circumferential transmission. In this way, the axial spline pair 4 can be used to axially position and transmit torque between the drive shaft 1 and the hub bearing 2.

[0036] It is understandable that when at least a portion of the drive shaft 1 is extended into the hub bearing 2, precise radial alignment can be achieved through the radial spline pair 3, reducing the meshing accuracy requirements and assembly difficulty of the axial spline pair 4, reducing the possibility of failure of the axial spline pair 4 due to tooth breakage, and the torque can be transmitted jointly by the radial spline pair 3 and the axial spline pair 4, so that the load can be adaptively distributed according to its own stiffness, which can improve the torque carrying capacity of the drive shaft assembly 100 and help extend the service life of the drive shaft assembly 100.

[0037] According to an embodiment of the present invention, the drive shaft assembly 100 forms a radial spline pair 3 by engaging a plurality of first spline portions 11 and a plurality of first spline mating portions 21 in a one-to-one correspondence to perform circumferential transmission between the drive shaft 1 and the hub bearing 2, and forms an axial spline pair 4 by engaging a plurality of second spline portions 12 and a plurality of second spline mating portions 22 in a one-to-one correspondence to perform circumferential transmission between the drive shaft 1 and the hub bearing 2. Radial positioning can be achieved through the radial spline pair 3, thereby reducing the meshing accuracy requirements and assembly difficulty of the axial spline pair 4, reducing the possibility of failure of the axial spline pair 4 due to tooth breakage, and improving the torque carrying capacity of the drive shaft assembly 100 by jointly transmitting torque through the radial spline pair 3 and the axial spline pair 4, which is beneficial to extending the service life of the drive shaft assembly 100.

[0038] In some embodiments, the drive shaft 1 includes a shaft body 13 and a first connecting shaft 14 connected axially. The shaft body 13 has a first connecting end face 131 formed at one end near the first connecting shaft 14. At least a portion of the first connecting shaft 14 is adapted to extend into the hub bearing 2 so that the first connecting end face 131 abuts against the end of the hub bearing 2. A first spline portion 11 is provided on the outer peripheral wall of the first connecting shaft 14, and a second spline portion 12 is provided on the first connecting end face 131.

[0039] Specifically, such as Figure 1 , Figure 3 and Figure 4 As shown, the drive shaft 1 includes a shaft body 13 and a first connecting shaft 14. Both the shaft body 13 and the first connecting shaft 14 can be part of the drive shaft 1. The shaft body 13 and the first connecting shaft 14 are connected axially, so that both the shaft body 13 and the first connecting shaft 14 are constructed to extend along the axial direction of the drive shaft 1, so that one end of the shaft body 13 and one end of the first connecting shaft 14 can be connected. For example, the connection can be made by welding, so that the drive shaft 1 can be a whole structure, which helps to improve the overall strength and operational reliability of the drive shaft 1.

[0040] Furthermore, at least a portion of the first connecting shaft 14 is adapted to extend into the hub bearing 2, so that when at least a portion of the drive shaft 1 is extended into the hub bearing 2, at least a portion of the first connecting shaft 14 can be located within the hub bearing 2. And by providing the first spline portion 11 on the outer peripheral wall of the first connecting shaft 14, when at least a portion of the first connecting shaft 14 is extended into the hub bearing 2, the first spline portion 11 located on the outer peripheral wall of the first connecting shaft 14 can engage with the first spline mating portion 21 located on the inner peripheral wall of the hub bearing 2 to form a radial spline pair 3.

[0041] Furthermore, the shaft body 13 has a first connecting end face 131 formed at one end near the first connecting shaft 14. When at least a portion of the first connecting shaft 14 is extended into the hub bearing 2, the first connecting end face 131 can be pressed against the end of the hub bearing 2. The second spline portion 12 is provided on the first connecting end face 131. When the first connecting end face 131 is pressed against the end of the hub bearing 2, the second spline portion 12 located on the first connecting end face 131 can engage with the second spline mating portion 22 located at the end of the hub bearing 2 to form an axial spline pair 4.

[0042] In some embodiments, the hub bearing 2 includes an inner bearing ring 23, rolling elements, and an outer bearing ring 24 arranged radially from the inside to the outside. The inner bearing ring 23 is provided with a first spline mating portion 21, and a second connecting end face 231 is formed at the end of the inner bearing ring 23. The second spline mating portion 22 is provided on the second connecting end face 231.

[0043] Specifically, such as Figures 2-4 As shown, the hub bearing 2 includes an inner ring 23, rolling elements, and an outer ring 24. The inner ring 23, rolling elements, and outer ring 24 are arranged sequentially from the inside to the outside along the radial direction of the hub bearing 2. The rolling elements are positioned between the inner ring 23 and the outer ring 24, allowing the inner ring 23 and the outer ring 24 to rotate relative to each other through the rolling elements. This, in turn, allows the components connected to the inner ring 23 and the outer ring 24 to rotate relative to each other through the rolling elements.

[0044] The bearing inner ring 23 is provided with a first spline mating part 21. When at least a portion of the first connecting shaft 14 is extended into the hub bearing 2, at least a portion of the first connecting shaft 14 can be extended into the bearing inner ring 23, thereby allowing the first spline part 11 located on the outer peripheral wall of the first connecting shaft 14 to mesh with the first spline mating part 21 located on the inner peripheral wall of the bearing inner ring 23 to form a radial spline pair 3. At the same time, a second connecting end face 231 is formed at the end of the bearing inner ring 23. The second spline mating part 22 is provided on the second connecting end face 231, so that when at least a portion of the first connecting shaft 14 is extended into the bearing inner ring 23, the first connecting end face 131 and the second connecting end face 231 can press against each other, thereby allowing the second spline part 12 located on the first connecting end face 131 to mesh with the second spline mating part 22 located on the second connecting end face 231 to form an axial spline pair 4.

[0045] In some embodiments, the drive shaft 1 further includes a second connecting shaft 15, which is connected to one end of the first connecting shaft 14 away from the shaft body 13. The second connecting shaft 15 is used to connect with the connector 5 after the first connecting shaft 14 extends into the inner ring 23 of the bearing so that the hub bearing 2 and the drive shaft 1 are pre-tightened axially.

[0046] Specifically, such as Figure 1 and Figure 3 As shown, the drive shaft 1 also includes a second connecting shaft 15, which can also be constructed as part of the drive shaft 1. The second connecting shaft 15 is connected to the end of the first connecting shaft 14 away from the shaft body 13, so that the second connecting shaft 15 can be constructed to extend along the axial direction of the drive shaft 1. Then, one end of the first connecting shaft 14 can be connected to the shaft body 13 and the other end can be connected to the second connecting shaft 15. For example, the connection can be made by welding, so that the drive shaft 1 can be a whole structure, which is beneficial to improving the overall strength and working reliability of the drive shaft 1.

[0047] Furthermore, the second connecting shaft 15 is used to connect with the connecting member 5 after the first connecting shaft 14 extends into the inner ring 23 of the bearing, so as to pre-tighten the hub bearing 2 and the drive shaft 1 axially. That is, after at least a part of the first connecting shaft 14 extends into the inner ring 23 of the bearing, at least a part of the second connecting shaft 15 can extend out from the inner ring 23 of the bearing, so as to connect the second connecting shaft 15 with the connecting member 5, so that the connecting member 5 can press the inner ring 23 of the bearing toward the shaft body 13, thereby pre-tightening the hub bearing 2 and the drive shaft 1 axially to ensure the reliable operation of the axial spline pair 4.

[0048] In some embodiments, the second connecting shaft 15 is provided with a threaded portion 151, the connecting member 5 is constructed as a connecting nut, and a threaded mating portion is formed inside the connecting nut, the threaded mating portion and the threaded portion 151 are threadedly engaged.

[0049] Specifically, the second connecting shaft 15 can be connected to the connecting member 5. A threaded portion 151 is provided on the outside of the second connecting shaft 15, and the connecting member 5 is constructed as a connecting nut. A threaded mating portion is formed inside the connecting nut. The threaded mating portion and the threaded portion 151 are threadedly engaged. That is, the second connecting shaft 15 can be connected to the connecting member 5 through the engagement of the threaded portion 151 and the threaded mating portion. An external thread can be formed on the outer peripheral wall of the second connecting shaft 15, and an internal thread can be formed on the inner peripheral wall of the connecting nut. When connecting the connecting nut to the second connecting shaft 15, the connecting nut can be sleeved on the outside of the second connecting shaft 15, and the connecting nut and the second connecting shaft 15 can be connected by screwing through the threaded engagement of the external and internal threads. This allows the second connecting shaft 15 to be connected to the connecting member 5 so that the hub bearing 2 and the drive shaft 1 are pre-tightened axially.

[0050] In some embodiments, the outer diameter of the first connecting shaft 14 is greater than the outer diameter of the second connecting shaft 15 and less than the minimum outer diameter of the shaft body 13.

[0051] Specifically, the shaft body 13, the first connecting shaft 14, and the second connecting shaft 15 are arranged sequentially and connected along the axial direction of the drive shaft 1. The first connecting shaft 14 is adapted to extend into the inner ring 23 of the hub bearing 2. The shaft body 13 has a first connecting end face 131 at one end facing the first connecting shaft 14. The first connecting end face 131 is adapted to press against the second connecting end face 231 on the inner ring 23 of the bearing after the first connecting shaft 14 extends into the inner ring 23 of the bearing. The second connecting shaft 15 is adapted to connect with the connecting member 5 after the first connecting shaft 14 extends into the inner ring 23 of the bearing, so that the drive shaft 1 can be extended into the inner ring 23 of the bearing from the end of the second connecting shaft 15 away from the first connecting shaft 14.

[0052] Specifically, by constructing the outer diameter of the first connecting shaft 14 to be larger than the outer diameter of the second connecting shaft 15 but smaller than the minimum outer diameter of the shaft body 13, the outer diameter of the second connecting shaft 15 can be constructed to be smaller than the outer diameter of the first connecting shaft 14. This ensures that the second connecting shaft 15 can extend out of the bearing inner ring 23 when the first connecting shaft 14 is inserted into the bearing inner ring 23, thereby ensuring a reliable connection between the second connecting shaft 15 and the connecting member 5. Furthermore, the shaft body 13 can be constructed as a multi-segment structure, with the minimum outer diameter of the shaft body 13 being larger than the outer diameter of the first connecting shaft 14. This ensures that the shaft body 13 can make abutting contact with the end of the bearing inner ring 23 when the first connecting shaft 14 is inserted into the bearing inner ring 23, thereby ensuring a reliable fit between the first connecting end face 131 and the second connecting end face 231, and thus ensuring the reliable operation of the axial spline pair 4.

[0053] In some embodiments, the drive shaft 1 is provided with an outer chamfer 16, and the hub bearing 2 is provided with an inner chamfer 25. The outer chamfer 16 and the inner chamfer 25 are matched, and the outer chamfer 16 and the inner chamfer 25 are used to guide the drive shaft 1 and the hub bearing 2 to be aligned and fitted.

[0054] Specifically, the drive shaft 1 is provided with an outer chamfer 16, which is constructed to be close to the axis of the drive shaft 1 in the direction close to the hub bearing 2. The outer chamfer 16 can serve as a guide. At the same time, the hub bearing 2 is provided with an inner chamfer 25, which is constructed to be far away from the axis of the hub bearing 2 in the direction close to the drive shaft 1. The inner chamfer 25 can also serve as a guide. The outer chamfer 16 and the inner chamfer 25 are matched, so that the outer chamfer 16 and the inner chamfer 25 can be set in correspondence, so that the outer chamfer 16 and the inner chamfer 25 can be used together to guide the drive shaft 1 and the hub bearing 2 to align and cooperate. When at least part of the drive shaft 1 is extended into the hub bearing 2, the relative sliding of the outer chamfer 16 and the inner chamfer 25 can play a guiding role in the initial stage of assembly, so as to prevent collision damage to the radial spline pair 3 or the axial spline pair 4.

[0055] In other embodiments, a guide portion may be provided at the center of the end face of the second connecting shaft 15 away from the first connecting shaft 14. The guide portion may be constructed as a short cylindrical boss structure and may form a clearance fit with the inner hole of the bearing inner ring 23 of the hub bearing 2 to play an auxiliary centering role before final pressing and to provide additional shear protection in extreme cases.

[0056] In some embodiments, the outer chamfer 16 is provided at the end of the first connecting shaft 14, and the inner chamfer 25 is provided on the side of the first spline mating part 21 near the second connecting end face 231.

[0057] Specifically, the outer chamfer 16 is positioned at the end of the first connecting shaft 14, and the inner chamfer 25 is positioned on the side of the first spline mating part 21 near the second connecting end face 231. This allows the outer chamfer 16 to be located at the end of the first connecting shaft 14 facing the hub bearing 2 before the first connecting shaft 14 is extended into the bearing inner ring 23. This also allows the outer chamfer 16 to be located at the end of the first spline part 11 facing the first spline mating part 21, and the inner chamfer 25 to be located at the end of the first spline mating part 21 facing the drive shaft 1. This also allows the inner chamfer 25 to be located at the end of the first spline mating part 21 facing the first spline part 11. In this way, when the first connecting shaft 14 is extended into the bearing inner ring 23, the outer chamfer 16 can first contact the inner chamfer 25 for reliable guidance. Then, the first spline part 11 and the first spline mating part 21 engage to achieve circumferential transmission between the first connecting shaft 14 and the bearing inner ring 23.

[0058] In some embodiments, the first spline portion 11 is configured as a radially external spline, the first spline mating portion 21 is configured as an internal spline groove, the radially external spline meshes with the internal spline groove, and the radially external spline is configured as an involute tooth shape; the second spline portion 12 is configured as a face spline, the second spline mating portion 22 is configured as a face spline groove, and the face spline meshes with the face spline groove.

[0059] Specifically, the first spline portion 11 can engage radially with the first spline mating portion 21 to form a radial spline pair 3. The first spline portion 11 is constructed as a radial external spline, allowing the first spline portion 11 to extend radially for a certain length. The first spline mating portion 21 is constructed as an internal spline groove, allowing the first spline mating portion 21 to extend radially for a certain length. Thus, when the first connecting shaft 14 is extended into the inner ring 23 of the bearing, the first spline portion 11 can extend into the first spline mating portion 21, allowing the radial external spline to engage with the internal spline groove to form a radial spline pair 3. The radial external spline is constructed as an involute tooth shape, so that it can have sufficient engagement length to provide good lateral support and torsional stiffness, thereby providing accurate radial positioning and partial torque transmission.

[0060] Meanwhile, the second spline portion 12 can engage with the second spline mating portion 22 axially to form an axial spline pair 4. The second spline portion 12 is constructed as an end face spline, so that the second spline portion 12 can extend a certain length axially. The second spline mating portion 22 is constructed as an end face spline groove, so that the second spline mating portion 22 can extend a certain length axially. In this way, when the first connecting end face 131 and the second connecting end face are pressed together, the second spline portion 12 can extend into the second spline mating portion 22, so that the end face spline and the end face spline groove can engage to form an axial spline pair 4.

[0061] In practice, the end face spline can be constructed as a straight tooth or a modified tooth profile, so that the axial spline pair 4 and the radial spline pair 3 are aligned in the circumferential direction or maintain a specific phase relationship, so that the axial spline pair 4 can bear the main torque transmission and provide axial positioning under the action of axial preload. The tooth height of the end face spline can be specially designed to ensure sufficient contact area under the rated preload.

[0062] In other embodiments, the end face spline may also use arc teeth, trapezoidal teeth, etc. to optimize contact stress, and the radial external spline may use a short tooth design with a large pressure angle to focus on positioning function.

[0063] It should be noted that the radial spline pair 3 and the axial spline pair 4 do not work independently. The radial spline pair 3 first guides the assembly and achieves initial positioning. Subsequently, the axial spline pair 4 engages during the clamping process. When transmitting torque, the system automatically distributes the load in parallel according to the stiffness of the two, avoiding overload of a single force transmission path. Moreover, the dual-path transmission makes the total torque capacity 1.5-2.5 times that of a single method, which can transmit a large torque of 20,000 N.m to meet the strong power of new energy vehicles, withstand large torque, and meet the requirements of NVH performance, reliability, and durability. The radial load is borne by the radial spline pair 3, while the torsional load is mainly borne by the axial spline pair 4, which greatly reduces the tooth surface contact stress, avoids stress concentration, and the optimized load distribution can significantly reduce wear and fatigue damage, extend the service life by 1.5-2.5 times, and can reach a service life of 1 million kilometers. It also has redundancy fault capability. If one set of spline pairs fails, the other set of spline pairs can maintain basic functions.

[0064] Of the torque, some can be transmitted through the tooth flanks of the radial spline pair 3, which can transmit 20%-40% of the torque. Most of the torque can be transmitted through the axial pressure on the tooth surface of the axial spline pair 4, which can transmit 60%-80% of the torque.

[0065] Furthermore, in the drive shaft assembly 100 of this embodiment, the first spline portion 11 and the second spline portion 12 on the drive shaft 1 can be made of low-carbon alloy steel to ensure core toughness and suitability for surface hardening treatment. The bearing inner ring 23 of the hub bearing 2 can be made of high-carbon chromium bearing steel to ensure overall wear resistance and contact fatigue strength. Moreover, to ensure that the connecting part 5 has a long service life under high alternating loads, the following key process needs to be performed: the first spline portion 11 and the second spline portion 12 of the drive shaft 1 are carburized to obtain a deep, high-hardness surface. The wear-resistant layer should maintain the toughness of the core while ensuring the surface hardness reaches a high Rockwell hardness value (such as HRC58 or above). The hardness of the inner ring 23 of the wheel hub bearing 2 can be slightly lower than the hardness of the first spline portion 11 and the second spline portion 12 of the drive shaft 1, forming a reasonable hardness gradient. This helps to protect the wheel hub bearing 2, which is more valuable and less likely to be replaced, under abnormal working conditions. Furthermore, the tooth surfaces of the radial spline pair 3 and the axial spline pair 4 can be phosphated or otherwise coated to form a porous lubrication carrier layer, improving the initial break-in performance and enhancing rust prevention.

[0066] It should be noted that, in practice, the materials of the first spline portion 11 and the second spline portion 12 are not limited to those described in this embodiment. They can be flexibly selected according to requirements, provided that the toughness of the core is guaranteed and the surface hardening treatment is appropriate. The processing technology of the first spline portion 11 and the second spline portion 12 is also not limited to those described in this embodiment. It can be flexibly selected according to requirements, provided that the wear-resistant layer on the surface and the toughness of the core are guaranteed. Furthermore, the hardness of the bearing inner ring 23, the hardness of the first spline portion 11, and the hardness of the second spline portion 12 can also be flexibly selected according to the actual situation. Moreover, the treatment method of the tooth surface of the radial spline pair 3 and the axial spline pair 4 can also be flexibly selected according to the actual situation, which can improve the flexibility of the setup.

[0067] Furthermore, proper assembly is crucial to ensuring connection performance; the specific steps can be as follows: ① Thoroughly clean the first spline portion 11 and the second spline portion 12 of the drive shaft 1, as well as the first spline mating portion 21 and the second spline mating portion 22 of the hub bearing 2, to ensure that there are no dirt or burrs.

[0068] ② Align the end of the drive shaft 1 with the inner hole of the hub bearing 2, and gently push it in manually using the outer chamfer 16 and the inner chamfer 25 until the radial spline pair 3 is initially engaged.

[0069] ③ Connect the second connecting shaft 15 to the connecting piece 5. A "torque + angle" control method is used for tightening: First, tighten the connecting piece 5 to a set initial torque to eliminate most of the gap; then, based on this, rotate it by a precisely set angle. This method can stably and accurately apply the axial preload required by the design, ensuring that the axial spline pair 4 reaches the expected compression state and contact stress. The final tightening torque / angle value needs to be determined based on design calculations and experiments.

[0070] The assembly verification method can be as follows: After assembly, a small, known verification torque can be applied to the hub bearing 2, the relative torsional angle can be measured, and the value can be compared with the benchmark value of the qualified sample to indirectly verify whether the radial spline pair 3 and the axial spline pair 4 are fully and correctly meshed in place.

[0071] Performance verification methods include: Static overtorque test: The drive shaft assembly 100 is slowly subjected to an increasing torsional torque on a test bench until the target torque is reached. The evaluation indicators include: whether permanent deformation or failure occurs before the target torque is reached, and whether the failure mode is a gradual overload failure rather than brittle fracture.

[0072] High-cycle fatigue test: On a hydraulic pulse test bench, alternating positive and negative torques are applied to the drive shaft assembly 100. The number of cycles must reach the millions. After the test, the tooth surface must be checked and no fatigue spalling or cracks that affect the function should appear, and the residual deformation must be within the allowable range.

[0073] Dynamic impact test: Simulate extreme vehicle operating conditions (such as rapid acceleration, bump crossing impact), apply high amplitude, short duration torque impact pulse, repeat multiple times, the connection must not be loose after the test, and the function must be intact.

[0074] It should be noted that the drive shaft assembly 100 of this embodiment can also be applied to other mechanical transmission fields that require high torque and high reliability of shaft-hub connections.

[0075] The present invention also proposes a vehicle.

[0076] The vehicle according to embodiments of the present invention includes a drive shaft assembly 100 of any of the above embodiments. The drive shaft assembly 100 includes a drive shaft 1 and a hub bearing 2. When at least a portion of the drive shaft 1 is extended into the hub bearing 2, a first spline portion 11 on the drive shaft 1 and a first spline mating portion 21 on the hub bearing 2 are meshed to form a radial spline pair 3 for circumferential transmission between the drive shaft 1 and the hub bearing 2, and a second spline portion 12 on the drive shaft 1 and a second spline mating portion 22 on the hub bearing 2 are meshed to form an axial spline pair 4 for circumferential transmission between the drive shaft 1 and the hub bearing 2.

[0077] Radial positioning can be achieved through radial spline pair 3, thereby reducing the meshing accuracy requirements and assembly difficulty of axial spline pair 4, reducing the possibility of failure of axial spline pair 4 due to tooth breakage, and allowing torque to be transmitted through both radial spline pair 3 and axial spline pair 4. That is, torque can be transmitted to the hub bearing 2 through two paths simultaneously, thereby improving the torque carrying capacity of drive shaft assembly 100 and extending the service life of drive shaft assembly 100. Furthermore, by setting the outer chamfer 16 and the inner chamfer 25, guidance can be provided in the initial stage of assembly to prevent damage to the first spline part 11 or the first spline mating part 21. By connecting the second connecting shaft 15 to the connecting piece 5 to axially preload the drive shaft 1 and the hub bearing 2, the tight meshing and reliable operation of axial spline pair 4 can be ensured.

[0078] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0079] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A drive shaft assembly, characterized in that, include: A drive shaft (1) is provided with a plurality of first spline portions (11) arranged sequentially along the circumference outside the drive shaft (1), and a plurality of second spline portions (12) arranged sequentially along the circumference at the end of the drive shaft (1). The hub bearing (2) has multiple first spline mating parts (21) arranged in a circumferential direction, and multiple second spline mating parts (22) arranged in a circumferential direction at the end of the hub bearing (2). At least a portion of the drive shaft (1) passes through the hub bearing (2), and a plurality of first spline portions (11) and a plurality of first spline mating portions (21) mesh one-to-one to form radial spline pairs (3) so that the hub bearing (2) and the drive shaft (1) can perform circumferential transmission. A plurality of second spline portions (12) and a plurality of second spline mating portions (22) mesh one-to-one to form axial spline pairs (4) so ​​that the hub bearing (2) and the drive shaft (1) can perform circumferential transmission.

2. The drive shaft assembly according to claim 1, characterized in that, The drive shaft (1) includes a shaft body (13) and a first connecting shaft (14) connected axially. The shaft body (13) has a first connecting end face (131) formed at one end near the first connecting shaft (14). At least a portion of the first connecting shaft (14) is adapted to extend into the hub bearing (2) so that the first connecting end face (131) abuts against the end of the hub bearing (2). The first spline portion (11) is disposed on the outer peripheral wall of the first connecting shaft (14), and the second spline portion (12) is disposed on the first connecting end face (131).

3. The drive shaft assembly according to claim 2, characterized in that, The hub bearing (2) includes an inner bearing ring (23), rolling elements and an outer bearing ring (24) arranged radially from the inside to the outside. The inner bearing ring (23) is provided with the first spline mating part (21). The end of the inner bearing ring (23) is formed with a second connecting end face (231). The second spline mating part (22) is provided on the second connecting end face (231).

4. The drive shaft assembly according to claim 3, characterized in that, The drive shaft (1) further includes a second connecting shaft (15), which is connected to one end of the first connecting shaft (14) away from the shaft body (13). The second connecting shaft (15) is used to connect with the connector (5) after the first connecting shaft (14) extends into the inner ring (23) of the bearing so that the hub bearing (2) and the drive shaft (1) are pre-tightened axially.

5. The drive shaft assembly according to claim 4, characterized in that, The second connecting shaft (15) is provided with a threaded part (151). The connecting piece (5) is constructed as a connecting nut. A threaded mating part is formed inside the connecting nut. The threaded mating part is threadedly engaged with the threaded part (151).

6. The drive shaft assembly according to claim 4, characterized in that, The outer diameter of the first connecting shaft (14) is greater than the outer diameter of the second connecting shaft (15) and less than the minimum outer diameter of the shaft body (13).

7. The drive shaft assembly according to claim 3, characterized in that, The drive shaft (1) has an outer chamfer (16) on its outside and the hub bearing (2) has an inner chamfer (25) on its inside. The outer chamfer (16) matches the inner chamfer (25). The outer chamfer (16) and the inner chamfer (25) are used to guide the drive shaft (1) and the hub bearing (2) to be aligned and fitted.

8. The drive shaft assembly according to claim 7, characterized in that, The outer chamfer (16) is located at the end of the first connecting shaft (14), and the inner chamfer (25) is located on the side of the first spline mating part (21) near the second connecting end face (231).

9. The drive shaft assembly according to claim 1, characterized in that, The first spline portion (11) is constructed as a radial external spline, the first spline mating portion (21) is constructed as an internal spline groove, the radial external spline meshes with the internal spline groove, and the radial external spline is constructed as an involute tooth shape; The second spline portion (12) is constructed as an end face spline, and the second spline mating portion (22) is constructed as an end face spline groove, wherein the end face spline meshes with the end face spline groove.

10. A vehicle, characterized in that, Includes the drive shaft assembly according to any one of claims 1-9.

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