Electric drive assembly and vehicle
By introducing tooth end, tooth direction, and tooth profile positioning structures into the electric drive assembly, the vibration and noise problems caused by the internal and external spline clearances are solved, and the NVH performance of the electric drive assembly is improved.
Patent Information
- Application Number
- CN202520018282.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-03
- Publication Date
- 2025-12-16
- Estimated Expiration
- 2035-01-03
AI Technical Summary
In existing electric drive assemblies, the tooth backlash between the inner and outer splines causes vibration and noise during acceleration and high-speed operation.
By employing tooth end positioning structure, tooth direction positioning structure, and tooth profile positioning structure, the radial movement of the motor shaft and the contact imbalance in the circumferential direction are limited through the meshing of the first tooth and the second tooth, thereby reducing noise.
It effectively reduces noise caused by radial misalignment runout and contact imbalance, and improves the NVH performance of the electric drive assembly.
Smart Images
Figure CN223680898U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to the electric drive field, in particular to an electric drive assembly and a vehicle. BACKGROUND
[0002] The power is transmitted between the motor shaft and the input shaft of the electric drive assembly by internal and external spline engagement. The existing electric drive assembly drives and positions by the tooth side of the external spline. The straight teeth of the external spline exist tooth side gap with the internal spline. Due to the existence of the tooth side gap, under the conditions of acceleration and high speed, the internal and external spline will vibrate and make noise due to centrifugal force. CONTENT OF THE UTILITY MODEL
[0003] The application provides an electric drive assembly and a vehicle capable of reducing noise.
[0004] The application provides an electric drive assembly, comprising: a motor and an input shaft, the motor comprising a motor shaft, the motor shaft comprising opposite first and second ends, the second end being provided with an external spline, the external spline comprising a plurality of first teeth; the input shaft comprising opposite third and fourth ends, the third end being provided with an internal spline, the internal spline comprising a plurality of second teeth, the first teeth and the second teeth being engaged, the motor shaft rotating with the input shaft, the first teeth and the second teeth being provided with tooth end positioning structure, tooth direction positioning structure and tooth shape positioning structure.
[0005] Further, the tooth end positioning structure comprises a first abutting portion provided on the first tooth and a second abutting portion provided on the internal spline, the first abutting portion and the second abutting portion abutting to limit the movement of the motor shaft in the radial direction thereof.
[0006] Further, the tooth shape positioning structure comprises a first protruding portion extending in the radial direction of the motor shaft and protruding outward.
[0007] Further, the first protruding portion comprises a first concave-convex structure.
[0008] Further, the tooth direction positioning structure comprises a second protruding portion extending in the axial direction of the motor shaft and protruding outward.
[0009] Further, the second protruding portion comprises a second concave-convex structure.
[0010] Further, the input shaft is provided with a receiving cavity, the internal spline is located in the receiving cavity, and the second end is received in the receiving cavity.
[0011] Further, the electric drive assembly comprises a first bearing, a second bearing and a third bearing, a first end of the motor shaft is fixed with a first inner ring of the first bearing, a third end of the input shaft is fixed with a second inner ring of the second bearing, and a fourth end of the input shaft is fixed with a third inner ring of the third bearing.
[0012] Further, the inner spline is located between the second bearing and the third bearing.
[0013] The application also provides a vehicle comprising the electric drive assembly.
[0014] In some embodiments, a tooth end positioning structure, a tooth direction positioning structure and a tooth shape positioning structure are arranged between the first tooth of the outer spline of the motor shaft and the second tooth of the inner spline of the input shaft of the electric drive assembly of the application, the tooth end positioning structure avoids the transient impact noise caused by the radial misalignment jump during acceleration and high speed, and the tooth direction positioning structure and the tooth shape positioning structure avoid the impact noise caused by the contact imbalance due to accumulated error and shape error in the circumferential direction under the conditions of forward movement and coasting, reduce the impact / vibration energy under different conditions, and reduce the noise. BRIEF DESCRIPTION OF DRAWINGS
[0015] Figure 1 is an exploded view of the electric drive assembly of the exemplary embodiment of the application;
[0016] Figure 2 is a cross-sectional view of the electric drive assembly shown in Figure 1
[0017] Figure 3 is a schematic view of the engagement of the inner spline of the input shaft and the outer spline of the motor shaft, wherein only a part of the motor shaft and the input shaft are shown; Figure 2
[0018] Figure 4 is an enlarged view of the circled part of the first tooth at A shown in Figure 3
[0019] Figure 5 is an exploded view of the first bearing shown in Figure 1
[0020] Figure 6 is a schematic view of the retainer of the first bearing shown in Figure 5
[0021] Figure 7 is a schematic view of another view of the retainer shown in Figure 6
[0022] Explanation of reference numerals: 100, electric drive assembly; 1, motor; 11, motor shaft; 111, first end; 112, second end; 113, external spline; 114, first tooth; 1140, first abutting portion; 1141, tooth end; 1142, first protruding portion; 1143, first concave-convex structure; 2, input shaft; 21, third end; 212, internal spline; 2120, second abutting portion; 213, second tooth; 22, fourth end; 24, accommodation cavity; 3, first bearing; 31, first outer ring; 312, accommodation space; 32, first inner ring; 33, ball; 34, retainer; 341, base; 3411, inner side; 3412, outer side; 3413, weight-reducing hole; 3414, first side; 3415, second side; 342, ball pocket; 3420, ball pocket hole; 3421, bottom; 3422, second top end; 343, reinforcing portion; 3431, middle portion; 3432, first connecting portion; 3433, second connecting portion; 3434, first top end; 4, second bearing; 41, second outer ring; 42, second inner ring; 5, third bearing; 51, third outer ring; 52, third inner ring. DETAILED DESCRIPTION
[0023] The technical solutions in the embodiments (or, modes of implementation) of the present application will be described clearly and completely below with reference to the drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated.
[0024] If the application embodiments involve directional indications or positional relationships (such as up, down, left, right, front, back, inner, outer, top, bottom, center, vertical, horizontal, longitudinal, transverse, length, width, counterclockwise, clockwise, axial, radial, circumferential, etc.), such terms are only used to explain the relative positional relationship, movement, etc. between the components in a certain posture (as shown in the drawings); if the specific posture changes, the directional indication or positional relationship also changes accordingly. In addition, the terms "first", "second", etc. in the embodiments of the present application are only used for convenience of description, and cannot be understood as indicating or implying relative importance.
[0025] Referring to FIG. 1, an electric drive assembly 100 is provided. Figures 1 to 3 The electric drive assembly 100 comprises a motor 1 and an input shaft 2.
[0026] The motor 1 comprises a motor shaft 11. The motor shaft 11 comprises opposite first and second ends 111 and 112. The second end 112 is provided with an external spline 113. The external spline 113 comprises a plurality of first teeth 114.
[0027] The input shaft 2 comprises a third end 21 and a fourth end 22 opposite to each other. The third end 21 is provided with an inner spline 212. The inner spline 212 comprises a plurality of second teeth 213.
[0028] The first teeth 114 are engaged with the second teeth 213, and the motor shaft 1 rotates with the input shaft 2.
[0029] The first teeth 114 and the second teeth 213 are provided with a tooth end positioning structure (not shown), a tooth direction positioning structure (not shown), and a tooth shape positioning structure (not shown). The tooth end positioning structure avoids the transient impact noise caused by the radial misalignment jump during acceleration and high speed. The tooth direction positioning structure and the tooth shape positioning structure avoid the impact noise caused by the contact imbalance due to accumulated error and shape error in the circumferential direction under the conditions of forward movement and sliding, reduce the impact / vibration energy under different conditions, and reduce noise to improve the NVH performance of the electric drive assembly 100.
[0030] In some embodiments, the tooth end positioning structure comprises a first abutting portion 1140 provided on the first teeth 114 and a second abutting portion 2120 provided on the inner spline 212. The first abutting portion 1140 and the second abutting portion 2120 abut to limit the movement of the motor shaft 11 in the radial direction thereof.
[0031] Referring to FIG. 1, the electric drive assembly 100 comprises a motor shaft 1 and an input shaft 2. The motor shaft 1 is provided with a plurality of first teeth 114. The input shaft 2 is provided with an inner spline 212. The first teeth 114 are engaged with the inner spline 212. Figure 3 In some embodiments, the first abutting portion 1140 is provided on the outer side of the tooth end 1141 of the first teeth 114, and the second abutting portion 2120 is provided on the input shaft 2 and located between two adjacent second teeth 213.
[0032] In some embodiments, the first abutting portion 1140 can also be provided on the side of the tooth end 114 of the first teeth 114, and the second abutting portion 2120 is provided on the side of the root of the second teeth 213.
[0033] In some embodiments, the tooth end positioning structure is arranged such that the tooth end 1141 of the first teeth 114 is in contact with the input shaft 2 without any gap therebetween.
[0034] In some embodiments, the tooth end positioning structure is arranged such that the gap between the tooth end 1141 of the first teeth 114 and the input shaft 2 is small, solving the abnormal impact noise in the forward movement and sliding conditions caused by the large gap.
[0035] In some embodiments, the safety design of the inner spline allowance of the inner spline 212 is achieved by using a complex broach with a large-diameter broaching; the convexity correction of the outer spline 113 is achieved by using a customized hob or a gear hob; and the large-diameter of the outer spline 113 is achieved by using a process of fine turning or grinding to ensure the accuracy.
[0036] Referring to Figure 3 In some embodiments, the tooth profile positioning structure includes a first protruding portion 1142 extending in the radial direction of the motor shaft 11 and protruding outward.
[0037] In some embodiments, the first protruding portion 1142 is arranged on the first tooth 114, and the first protruding portion 1142 can also be arranged on the second tooth 213.
[0038] In some embodiments, the protruding amount of the first protruding portion 1142 is related to the tooth length of the first tooth 114. By designing the protruding amount of the first protruding portion 1142, the circumferential contact friction is reduced, and the problem of impact noise in driving scenarios, acceleration, and energy recovery is reduced.
[0039] Referring to Figure 4 In some embodiments, the first protruding portion 1142 includes a first concave-convex structure 1143. The first tooth 114 of the outer spline 113 not only includes the first protruding portion 1142, but also includes the first concave-convex structure 1143, which has a better noise reduction effect.
[0040] In some embodiments, the tooth direction positioning structure includes a second protruding portion (not shown) extending in the axial direction of the motor shaft 11 and protruding outward.
[0041] In some embodiments, the second protruding portion is arranged on the first tooth 114, and the second protruding portion can also be arranged on the second tooth 213.
[0042] In some embodiments, the second protruding portion includes a second concave-convex structure (not shown). The first tooth 114 of the outer spline 113 not only includes the second protruding portion, but also includes the second concave-convex structure, which has a better noise reduction effect.
[0043] Referring to Figure 2 In some embodiments, the input shaft 2 is provided with a receiving cavity 24, the inner spline 212 is located in the receiving cavity 24, and the second end 112 of the motor shaft 11 is received in the receiving cavity 24.
[0044] In some embodiments, the electric drive assembly 100 includes a first bearing 3, a second bearing 4, and a third bearing 5.
[0045] The first end 111 of the motor shaft 11 is fixed to the first inner ring 32 of the first bearing 3, and the first outer ring 31 of the first bearing 3 is fixed to the housing (not shown) of the reducer (not shown) of the electric drive assembly 100, which can be directly fixed or indirectly fixed. For example, it can be fixed by a pressing plate, bolts, etc.
[0046] The third end 21 of the input shaft 2 is fixed to the second inner ring 42 of the second bearing 4, and the second outer ring 41 of the second bearing 4 is fixed to the housing (not shown) of the reducer (not shown) of the electric drive assembly 100, which can be directly fixed or indirectly fixed. For example, it can be fixed by a pressing plate, bolts, etc.
[0047] The fourth end 22 of the input shaft 2 is fixed to the third inner ring 52 of the third bearing 5. The third outer ring 51 of the third bearing 5 is fixed to the housing (not shown) of the reducer (not shown) of the electric drive assembly 100, which can be directly fixed or indirectly fixed. For example, it can be fixed by a pressing plate, bolts, etc.
[0048] In some embodiments, the internal spline 212 is located between the second bearing 4 and the third bearing 5.
[0049] In some embodiments, the distance between the internal spline 212 and the second bearing 4 is less than the distance between it and the third bearing 5.
[0050] Refer Figures 5 to 7 , in some embodiments, the first bearing 3 includes a first outer ring 31, a first inner ring 32, a cage 34 and a plurality of balls 33. The first inner ring 32 is located within the first outer ring 31, and the plurality of balls 33 are located within the receiving space 312 between the first inner ring 32 and the first outer ring 31, and rotate following the rotation of the first inner ring 32 or the first outer ring 31.
[0051] The cage 34 includes an annular base 341, a plurality of ball pockets 342 and a plurality of reinforcing parts 343.
[0052] The balls 33 are located within the ball pockets 3420 of the ball pockets 342. The balls 33 can also rotate within the ball pockets 3420. At high speeds, the ball pockets <0>承受周向运动下来自所述滚珠33的多重复杂载荷,且还要承受在随时加速度下的瞬态冲击负荷。
[0053] It should be noted that there is an unclear part in the original text of item . I have translated it as best as possible according to the context, but you may need to further confirm the accurate expression.In some embodiments, the bottom 3421 of the plurality of pocket ball portions 342 is connected to the base 341. The plurality of reinforcing portions 343 is respectively connected to two adjacent pocket ball portions 342, ensuring that the retainer 34 has better strength, so that the retainer 34 can withstand multiple complex loads from the balls 33 and also withstand transient impact loads under random acceleration; the retainer 34 has better strength, further improving the strength of the first bearing 3, and the first bearing 3 can withstand higher rotational speed.
[0054] In some embodiments, along the radial direction of the base 341, the width of the base 341 is greater than the thickness of the bottom 3421 of the pocket ball portion 342, ensuring that the retainer 34 has better strength, so that the retainer 34 can withstand multiple complex loads from the balls 33 and also withstand transient impact loads under random acceleration; the retainer 34 has better strength, further improving the strength of the first bearing 3, and the first bearing 3 can withstand higher rotational speed.
[0055] The base 341 includes an inner side 3411 and an outer side 3412 arranged along the radial direction thereof.
[0056] In some embodiments, along the radial direction of the base 341, the inner side 3411 extends beyond the bottom 3421 of the pocket ball portion 342, ensuring that the retainer 34 has better strength, further improving the strength of the first bearing 3.
[0057] In some embodiments, along the radial direction of the base 341, the outer side 3412 extends beyond the bottom 3421 of the pocket ball portion 342, ensuring that the retainer 34 has better strength, further improving the strength of the first bearing 3.
[0058] In some embodiments, along the radial direction of the base 341, the inner side 3411 and the outer side 3412 both extend beyond the bottom 3421 of the pocket ball portion 342, ensuring that the retainer 34 has better strength, further improving the strength of the first bearing 3.
[0059] In some embodiments, the overall thickness of the pocket ball portion 342 is uniform, facilitating processing and molding.
[0060] In some embodiments, along the radial direction of the base 341, the thickness of the reinforcing portion 343 is less than the thickness of the pocket ball portion 342, which is beneficial for the lightweight of the retainer 34.
[0061] In some embodiments, the bottom end of the 3rd reinforcing portion 43 is connected to the base 341, ensuring that the retainer 34 has better strength. The bottom end of the reinforcing portion 343 can also be disconnected from the base 341, leaving a gap therebetween.
[0062] In some embodiments, the reinforcing portion 343 comprises a middle portion 3431 and first and second connecting portions 3432 and 3433 located on both sides of the middle portion 3431. The first and second connecting portions 3432 and 3433 are respectively connected to two adjacent ball pocket portions 342. In the radial direction of the base 341, the middle portion 3431 protrudes from the first and second connecting portions 3432 and 3433, and the reinforcing portion 343 has better strength.
[0063] In some embodiments, the middle portion 3431 is cylindrical, and the present application does not limit the shape of the middle portion 3431.
[0064] In some embodiments, in the radial direction of the base 341, the middle portion 3431 only protrudes from the first connecting portion 3432 and does not protrude from the second connecting portion 3433.
[0065] In some embodiments, in the radial direction of the base 341, the middle portion 3431 only protrudes from the second connecting portion 3433 and does not protrude from the first connecting portion 3432.
[0066] In some embodiments, in the height direction perpendicular to the radial direction, the first top end 3434 of the reinforcing portion 343 is lower than the second top end 3422 of the ball pocket portion 342, which is conducive to the lightweight of the retainer 34.
[0067] In some embodiments, the base 341 is provided with a plurality of weight-reducing holes 3413 to reduce the weight of the retainer 34, which is conducive to the lightweight of the retainer 34.
[0068] In some embodiments, the retainer 34 is made of engineering reinforced plastic to reduce the weight of the retainer 34, while ensuring that the retainer 34 has better strength to have better yield strength at high speed and high acceleration, resisting deformation due to centrifugal force and load at high speed. The present application does not limit the material of the retainer 34.
[0069] The plurality of weight-reducing holes 3413 are sequentially arranged in the circumferential direction of the base 341. The plurality of weight-reducing holes 3413 are arranged in groups, and the first distance between two adjacent weight-reducing holes 3413 in a group is smaller than the second distance between two adjacent groups of weight-reducing holes.
[0070] In some embodiments, a plurality of the weight-reducing holes are evenly arranged along the circumferential direction of the base 341.
[0071] In Figure 6 In some embodiments, a plurality of the weight-reducing holes 3413 are arranged in groups of two. The number of the weight-reducing holes 3413 in each group is not limited in the present application.
[0072] In some embodiments, the weight-reducing holes 3413 are elliptical. The shape of the weight-reducing holes 3413 is not limited in the present application.
[0073] In some embodiments, the length direction of the weight-reducing holes 3413 is consistent with the circumferential direction of the base 341.
[0074] In some embodiments, the first side surface 3414 of the base 341 is concave-convex. The reinforcing portion 343 is arranged at the concave part of the base 341, and the ball pocket portion 342 is arranged at the convex part of the base 341, which is conducive to the lightweight of the retainer 34 and ensures that the retainer 34 has better strength.
[0075] The weight-reducing holes 3413 are recessed from the second side surface 3415 of the base 341 opposite to the first side surface 3414. The weight-reducing holes 3413 are arranged corresponding to the ball pocket portion 342, i.e., the weight-reducing holes 3413 are located on one side of the bottom 3421 of the ball pocket portion 342, so as to ensure that the retainer 34 has better strength.
[0076] In some embodiments, when the first bearing 3 is assembled, the first inner ring 32 is first assembled into the first outer ring 3, then a plurality of the balls 33 are assembled into the accommodation space 312 between the first inner ring 32 and the first outer ring 31, then the balls 33 are uniformly arranged, and finally the ball pocket hole 3420 of the retainer 34 is aligned with the balls 33 and is press-fitted. The assembly sequence of the first bearing 3 is not limited in the present application.
[0077] In some embodiments, the second bearing 4 has the same structure as the first bearing 3, which will not be described herein again. The second bearing 4 can also have a different structure from the first bearing 3.
[0078] In some embodiments, the third bearing 5 has the same structure as the first bearing 3, which will not be described herein again. The third bearing 5 can also have a different structure from the first bearing 3.
[0079] In some embodiments, the present application also provides a vehicle comprising the electric drive assembly.
[0080] It should be noted that the technical solutions or technical features described in the above embodiments can be combined or supplemented with each other without conflict. The scope of protection of the present application is not limited to the precise structure described in the above embodiments and shown in the accompanying drawings; any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the scope of protection of the present application.
Claims
1. An electric drive assembly, characterized in that, include: An electric motor includes a motor shaft, the motor shaft having a first end and a second end opposite to each other, the second end being provided with an external spline, the external spline including a plurality of first teeth; The input shaft includes a third end and a fourth end opposite to each other. The third end is provided with an internal spline. The internal spline includes a plurality of second teeth. The first teeth mesh with the second teeth. The motor shaft drives the input shaft to rotate. A tooth end positioning structure, a tooth direction positioning structure and a tooth profile positioning structure are provided between the first teeth and the second teeth.
2. The electric drive assembly according to claim 1, characterized in that, The tooth end positioning structure includes a first abutment top disposed on the first tooth and a second abutment top disposed on the internal spline. The first abutment top and the second abutment top abut against each other to restrict the movement of the motor shaft in its radial direction.
3. The electric drive assembly according to claim 1, characterized in that, The toothed positioning structure includes a first protrusion that extends radially along the motor shaft and bulges outward.
4. The electric drive assembly according to claim 3, characterized in that, The first protrusion includes a first concave-convex structure.
5. The electric drive assembly according to claim 1, characterized in that, The toothed positioning structure includes a second protrusion that extends outward along the axial direction of the motor shaft.
6. The electric drive assembly according to claim 5, characterized in that, The second protrusion includes a second concave-convex structure.
7. The electric drive assembly according to any one of claims 1 to 6, characterized in that, The input shaft has a receiving cavity, the internal spline is located in the receiving cavity, and the second end is received in the receiving cavity.
8. The electric drive assembly according to claim 7, characterized in that, The electric drive assembly includes a first bearing, a second bearing, and a third bearing. The first end of the motor shaft is fixed to the first inner ring of the first bearing, the third end of the input shaft is fixed to the second inner ring of the second bearing, and the fourth end of the input shaft is fixed to the third inner ring of the third bearing.
9. The electric drive assembly according to claim 8, characterized in that, The internal spline is located between the second bearing and the third bearing.
10. A vehicle, characterized in that, Includes the electric drive assembly as described in any one of claims 1 to 9.