Differential assembly and vehicle

Abstract

This utility model relates to an integrated differential assembly with high weight limitations. It includes a differential housing and a differential cover plate for axially sealing the differential housing. The differential housing has multiple protrusions on its axial end face facing the differential cover plate for fixing the differential cover plate. Each protrusion has a radially inwardly opening retaining ring groove, within which an elastic retaining ring is placed for axially fixing the differential cover plate. This utility model aims to solve the problem of high mass in existing differential assemblies, reducing the weight of the reducer assembly and the rotational inertia of the differential assembly, thereby improving transmission efficiency.

Description

Technical Field

[0001] This utility model relates to a differential assembly, and more particularly to a differential assembly that can be integrated into a reducer. Background Technology

[0002] With the global energy structure transformation and increasingly stringent environmental regulations, electric vehicles have become a core development direction in the transportation sector. However, the excessive weight of existing electric vehicles severely restricts their performance improvement and market competitiveness, making the need for lightweighting of electric vehicles particularly urgent.

[0003] Patent CN 118532454 A discloses a coaxial transmission and electric drive assembly, integrating the differential assembly into the coaxial transmission assembly. While achieving differential and deceleration functions, this design makes the transmission axially compact and reduces weight. However, in this invention, the differential cover is connected to the differential housing with 12 screws, resulting in significant weight and failing to meet lightweight requirements. Furthermore, the 12 screws increase the rotational inertia of the differential assembly, leading to increased energy consumption and reduced transmission efficiency.

[0004] Therefore, a lighter differential assembly needs to be designed to solve the above problems. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide an integrated differential assembly with lighter weight and smaller moment of inertia.

[0006] The aforementioned technical problem is solved by a differential assembly designed according to this utility model. This differential assembly includes a differential housing and a differential cover plate for axially sealing the differential housing. The differential housing has multiple protrusions on its axial end face facing the differential cover plate for fixing the differential cover plate. In this utility model, each protrusion has a radially inwardly opening retaining ring groove, within which an elastic retaining ring is placed for axially fixing the differential cover plate. This technical solution avoids the use of screws when assembling the differential housing and cover plate, reducing the weight of the differential assembly and its rotational inertia, thereby improving transmission efficiency.

[0007] According to a preferred embodiment of this utility model, the inner diameter of the retaining ring groove is larger than the diameter of the differential cover plate. The inner diameter of the retaining ring groove can be smaller than or equal to the diameter of the differential cover plate, forming an interference fit or a transition fit between the differential cover plate and the differential housing, thus fixing the differential cover plate to the differential housing. However, this assembly requires applying significant axial pressure to the differential cover plate and the differential housing, necessitating the use of specific equipment, which increases equipment purchase and maintenance costs, and prolongs assembly time, hindering large-scale production. Therefore, it is preferable that the inner diameter of the retaining ring groove is larger than the diameter of the differential cover plate. This results in a clearance fit between the differential cover plate and the differential housing, eliminating the need for specific equipment, reducing production costs and time, and facilitating large-scale production.

[0008] According to a preferred embodiment of this utility model, the differential assembly further includes at least one fixing pin. The end of the differential housing that connects to the differential cover plate has at least one mounting hole for installing the fixing pin. The differential cover plate has a positioning hole corresponding to the position of the fixing pin. The fixing pin circumferentially fixes the differential cover plate to the differential housing, thus preventing circumferential displacement of the differential cover plate relative to the differential housing, improving the stability and reliability of the differential assembly during operation. More preferably, the differential assembly also includes multiple bevel gears, with the number of fixing pins matching the number of bevel gears. The rotating shaft of the bevel gears is fixed to the differential housing through a through hole in the radial direction of the rotating shaft. This design allows for simultaneous fixing of both the bevel gears and the differential cover plate by extending the original fixing pins axially, eliminating the need to increase the number of fixing pins, reducing assembly parts, lowering production costs, and improving assembly efficiency. Even more preferably, the fixing pins and the through holes in the radial direction of the bevel gear rotating shafts are interference fits. Through an interference fit, both the bevel gear shaft and the retaining pin are securely fixed in the differential housing, preventing them from easily falling out during differential assembly operation and further improving the operational stability and reliability of the differential assembly. More preferably, the positioning holes on the differential cover are blind holes with a depth between 3mm and 5mm. Compared to through holes, blind holes better secure the retaining pin inside the differential housing, preventing it from falling out of the differential assembly during operation and causing equipment damage. The preferred depth of the positioning holes is 3mm to 5mm; this avoids both insufficient circumferential support from shallow holes leading to slippage and excessive depth from increasing processing costs and time.

[0009] According to a preferred embodiment of this utility model, the elastic retaining ring has a support lug, and the support lug is provided with an operating hole for inserting an installation tool. The operating hole facilitates the use of tools to clamp the elastic retaining ring, improving the convenience of installation and increasing assembly efficiency.

[0010] According to a preferred embodiment of the present invention, the number of protrusions on the differential housing is at least three, preferably corresponding to the number of bevel gears. This allows the protrusions to be positioned on the protrusions where the bevel gears are mounted, which helps to improve the strength of the protrusions. Furthermore, three or more protrusions can effectively restrict the elastic retaining ring, making it less likely for the elastic retaining ring to fall off.

[0011] Furthermore, the aforementioned technical problems can also be solved by vehicles equipped with any of the above-mentioned differential assemblies. Due to the optimized differential assembly design, the vehicle's weight is reduced, and because the differential assembly has a low moment of inertia, the vehicle can output more torque during acceleration, improving transmission efficiency and reducing energy consumption during driving. Further, the vehicle has a power unit integrating the differential assembly and the reduction gear assembly. Multiple planetary gear assemblies are integrated along the inner circumference of the differential housing. Each planetary gear assembly includes a coaxial first planetary gear and a second planetary gear. The differential assembly is mounted in a coaxial reduction gear assembly with a fixedly mounted external ring gear and a sun gear for power input. The first planetary gear meshes with the sun gear, and the second planetary gear meshes with the external ring gear. This design achieves coaxial input and output while also offering advantages such as compact structure and low weight. Attached Figure Description

[0012] The present invention will now be described in more detail with reference to the accompanying drawings, but this does not limit the overall concept of the invention.

[0013] Figure 1 This is a cross-sectional schematic diagram of the prior art;

[0014] Figure 2 This is a schematic diagram of the installation of the differential housing and differential cover in the prior art;

[0015] Figure 3 This is a schematic diagram of the differential assembly of this utility model;

[0016] Figure 4 This is a cross-sectional view of the differential assembly of this utility model;

[0017] Figure 5 This is a partial cross-sectional view of the differential assembly of this utility model;

[0018] Figure 6 This is an exploded view of the differential assembly of this utility model.

[0019] In this utility model, unless otherwise specified, "axial", "radial" and "circumferential" are all relative to the differential assembly. Detailed Implementation

[0020] Figure 1 , Figure 2This paper illustrates a coaxial transmission in the prior art that integrates a differential assembly, achieving both differential and deceleration functions while maintaining a compact axial structure and reducing weight. However, in... Figure 1 and Figure 2 In the illustrated design, the differential cover 3' is connected to the differential housing 1' by 12 screws 7, resulting in a relatively large overall weight of the transmission, which does not meet the requirements for lightweighting. Furthermore, the 12 screws 7 increase the rotational inertia of the differential assembly, leading to increased energy consumption and reduced transmission efficiency.

[0021] Figure 3 and Figure 4 A differential assembly designed according to this utility model is shown. For example... Figure 3 As shown, the differential assembly includes a differential housing 1 and a differential cover 3 for axially sealing the differential housing 1. The differential housing 1 has three protrusions 11 on its axial end face facing the differential cover 3 for fixing the differential cover 3. Each protrusion 11 has a radially inwardly opening retaining ring groove 111 (e.g., ...). Figure 5 As shown, an elastic retaining ring 4 for axially fixing the differential cover plate 3 is installed in the retaining ring groove 111. By eliminating the use of screws, the weight of the differential assembly is greatly reduced, and the rotational inertia of the differential assembly is also reduced, improving transmission efficiency. More preferably, the inner diameter of the retaining ring groove 111 is larger than the diameter of the differential cover plate 3. This results in a clearance fit between the differential cover plate 3 and the differential housing 1, which can be installed without specific installation equipment, reducing production costs and time, and facilitating mass production.

[0022] Figure 5 A partial cross-sectional view of a differential assembly designed according to this utility model is shown. The differential assembly is designed with three fixing pins 2. The end of the differential housing 1 that connects to the differential cover plate 3 has three mounting holes 12 for mounting the fixing pins 2. The differential cover plate 3 has three positioning holes 31 (e.g., at the positions of the fixing pins) at the corresponding locations of the fixing pins. Figure 6As shown, the retaining pin 2 circumferentially fixes the differential cover plate 3 to the differential housing 1. This prevents the differential cover plate 3 from shifting circumferentially relative to the differential housing 1, improving the stability and reliability of the differential assembly during operation. More preferably, the differential assembly also includes three bevel gears 5, and three retaining pins 2 fix the rotating shaft 51 of the bevel gears 5 to the differential housing 1 through radial through holes in the rotating shaft 51. This design allows for simultaneous fixing of the bevel gears 5 and the differential cover plate 3 by extending the retaining pin 2 axially from its original position, eliminating the need to increase the number of retaining pins 2, reducing assembly parts, lowering production costs, and improving assembly efficiency. Furthermore, the fit between the retaining pin 2 and the radial through hole in the rotating shaft 51 of the bevel gears 5 can be designed as an interference fit. Through an interference fit, both the rotating shaft 51 and the retaining pin 2 are firmly fixed in the differential housing 1, preventing them from easily falling off during differential assembly operation and further improving the operational stability and reliability of the differential assembly. More preferably, the positioning hole 31 on the differential cover plate 3 is designed as a blind hole with a depth between 3mm and 5mm. Compared to through holes, the blind hole design allows the retaining pin to be better secured inside the differential housing, preventing it from falling off during differential assembly operation and causing equipment damage. The preferred depth of the positioning hole 31 is 3mm to 5mm; this avoids both insufficient circumferential support from a shallow hole leading to slippage and disengagement, and excessive depth from increasing processing costs and time.

[0023] Figure 6 An exploded view of the differential assembly of this utility model is shown. The elastic retaining ring 4 is designed with a lug 41, and the lug 41 can be further designed with an operating hole for inserting an installation tool. The lug 41 and the operating hole facilitate the clamping operation of the elastic retaining ring 4 with a tool, improving the convenience of installation and the assembly efficiency.

[0024] exist Figures 3 to 6 In the illustrated embodiment, three sets of planetary gear assemblies 6 are integrated along the inner circumference of the differential housing 1. Each set of planetary gear assemblies 6 includes a coaxial first planetary gear 61 and a second planetary gear 62. The differential assembly is mounted in a coaxial reducer assembly with a fixedly mounted external ring gear and a sun gear for power input. The first planetary gear 61 meshes with the sun gear, and the second planetary gear 62 meshes with the external ring gear. This design achieves coaxial input and output while also offering the advantages of compact structure and low weight, further reducing weight.

[0025] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

[0026] List of reference numerals

[0027] 1.1' Differential housing

[0028] 11. Protrusion

[0029] 111 retaining ring groove

[0030] 12 mounting holes

[0031] 2, 2' Fixing pin

[0032] 3' Differential cover plate

[0033] 31 Positioning Holes

[0034] 4. Elastic retaining ring

[0035] 41 ears

[0036] 5. Bevel gears

[0037] 51 Rotating shaft

[0038] 6 Planetary gear assembly

[0039] 61 First Planetary Gear

[0040] 62 Second Planetary Gear

[0041] 7 screws

Claims

1. A differential assembly, comprising: The differential housing (1) and the differential cover plate (3) for axially sealing the differential housing (1) have a plurality of protrusions (11) for fixing the differential cover plate (3) on the axial end face of the differential housing (1) facing the differential cover plate (3), wherein the protrusions (11) have a retaining ring groove (111) with a radially inward opening, and an elastic retaining ring (4) for axially fixing the differential cover plate (3) is placed in the retaining ring groove (111).

2. The differential assembly of claim 1, wherein, The inner diameter of the retaining ring groove (111) is larger than the diameter of the differential cover plate (3).

3. The differential assembly according to claim 1, characterized in that, The differential assembly also has at least one retaining pin (2), and the end of the differential housing (1) that is connected to the differential cover plate (3) has at least one mounting hole (12) for mounting the retaining pin (2). The differential cover plate (3) has a positioning hole (31) corresponding to the position of the retaining pin. The retaining pin (2) circumferentially fixes the differential cover plate (3) to the differential housing (1).

4. The differential assembly of claim 3, wherein, The differential assembly also has a plurality of bevel gears (5), the number of fixing pins (2) is the same as the number of bevel gears (5), and the rotating shaft (51) of the bevel gears (5) is fixed in the differential housing (1) through a through hole in the radial direction of the rotating shaft (51).

5. The differential assembly of claim 4, wherein, The fixing pin (2) and the radial through hole of the rotating shaft (51) are interference fit.

6. The differential assembly of claim 3, wherein, The positioning hole (31) is a blind hole with a depth of 3mm to 5mm.

7. The differential assembly of claim 1, wherein The elastic retaining ring (4) has a lug (41) on which an operating hole for inserting an installation tool is provided.

8. The differential assembly of claim 1, wherein, The number of protrusions (11) is at least three.

9. A vehicle having a differential assembly according to any one of claims 1-8.

10. The vehicle of claim 9, wherein, The vehicle also has an integrated coaxial reducer assembly, wherein the differential housing (1) integrates multiple planetary gear assemblies (6) in the inner circumferential direction, the planetary gear assembly (6) including a coaxial first planetary gear (61) and a second planetary gear (62), the first planetary gear (61) meshing with a sun gear for the coaxial reducer assembly, and the second planetary gear (62) meshing with an external ring gear for the coaxial reducer assembly.

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