Oil seal structure, electric drive assembly and vehicle

Abstract

The oil seal structure comprises a framework and a sealing body, the sealing body is used for sealing connection with an assembly shell, an end of the sealing body is provided with a lip, the lip has elasticity, a mounting groove is formed on the assembly shell, the lip comprises a connecting portion and a clamping portion for clamping in the mounting groove, the connecting portion is arranged to be inclined from the sealing body to the axial direction of the framework, so that a gap is formed between the connecting portion and the assembly shell, and the clamping portion is folded outward along the end of the connecting portion in a hook shape. In this way, without affecting the normal use of the oil seal structure, the anti-disengagement design is made on the assembly shell and the oil seal structure, the oil seal structure can be effectively prevented from disengaging under the conditions of thermal expansion and cold shrinkage of the assembly shell, the adaptability of the oil seal structure to complex working conditions is improved, and the failure problems such as oil leakage caused by disengagement of the oil seal structure are avoided.

Description

Technical Field

[0001] This disclosure relates to the field of sealing structure technology, specifically to an oil seal structure, an electric drive assembly, and a vehicle. Background Technology

[0002] Oil seals are widely used sealing elements in mechanical equipment. Their core function is to prevent lubricating oil from leaking from gaps in machine parts (such as bearing housings and gearboxes) and to prevent external dust and impurities from entering.

[0003] In related technologies, oil seals are typically pressed into pre-machined mounting holes in the housing, relying on the interference fit between their metal skeleton and the mounting hole for initial fixation. Under normal static or low-pressure conditions, this interference fit usually meets the fixation requirements. However, as modern industrial equipment develops towards high speed, high pressure, and high load, the working environment of oil seals is becoming increasingly harsh. Traditional fixation methods have many problems. Within a closed cavity, equipment operation generates internal pressure. When the internal pressure is too high or there is pulsating pressure, the axial force acting on the back of the oil seal increases sharply. This axial force is sufficient to overcome the static friction between the skeleton and the mounting groove, pushing the oil seal out of the mounting seat, causing instantaneous seal failure and leading to serious oil leakage accidents. Temperature changes during equipment operation cause different thermal expansion and contraction of the rubber body of the oil seal and the metal mounting seat. This difference in the coefficient of thermal expansion of the materials may result in an overly tight fit during low-temperature startup and a loose fit during high-temperature operation, creating conditions for the oil seal to detach at high temperatures. Utility Model Content

[0004] The purpose of this disclosure is to provide an oil seal structure, an electric drive assembly, and a vehicle to at least partially solve the problems existing in the related art.

[0005] To achieve the above objectives, this disclosure provides an oil seal structure, including a skeleton and a sealing body. The sealing body is used for a sealing connection with an assembly housing. The sealing body has a lip at its end, and the lip is elastic. An mounting groove is formed on the assembly housing. The lip includes a connecting portion and a locking portion for engaging within the mounting groove. The connecting portion is axially inclined from the sealing body towards the skeleton to create a gap between the connecting portion and the assembly housing. The locking portion is folded outwards along the end of the connecting portion in a hook shape. Thus, stress is generated during the press-fitting process of the oil seal structure, causing the elastic lip to undergo elastic deformation. During press-fitting, the locking portion can bend to abut against the connecting portion, eliminating the gap. Therefore, the lip design does not affect the press-fitting process. After the oil seal structure is press-fitted into place, i.e., when the locking portion moves to the mounting groove, the lip will open, restoring its elastic deformation. The locking portion can then be tilted and engaged within the mounting groove to provide an anti-dislodgement function.

[0006] In some possible implementations, the locking portion extends partially into the mounting groove. This provides deformation space for the locking portion during press-fitting, during which the locking portion extends almost entirely into the mounting groove; after press-fitting is completed, the locking portion returns to its original shape, and the portion near the connecting part pops out of the mounting groove.

[0007] In some possible implementations, the intersection of the connecting portion and the locking portion is constructed with rounded corners. This configuration can significantly reduce stress concentration, as the rounded corners provide a smooth, gradual transition path for stress, allowing stress to be distributed evenly, thereby minimizing the stress concentration effect, extending the fatigue life of the seal, and enhancing structural rigidity and stability.

[0008] In some possible implementations, the cross-section of the connection is tapered. This configuration enables a smooth stress transition and reduces stress concentration.

[0009] In some possible implementations, the extension direction of the connecting portion is at an angle of 20° to 45° to the axial direction of the skeleton. The connecting portion is tilted to create a gap between it and the assembly housing, thereby providing space for the elastic deformation of the locking portion during press-fitting and avoiding interference with the press-fitting process.

[0010] In some possible implementations, the extension direction of the locking portion is at an angle of 30° to 60° to the axial direction of the skeleton. The locking portion, which is inclined and arranged in a barbed shape, can better prevent the oil seal structure from coming out after it extends into the mounting groove.

[0011] In some possible implementations, the lip is integrally formed with the sealing body. This integral design eliminates weak points in the connection, making it robust, durable, and offering better sealing and aesthetics. Because there are no seams or connection points, the integral design is ideal for components requiring leak-proof construction, such as oil seals.

[0012] In some possible implementations, the sealing body is interference-fitted with the assembly housing. The interference fit achieves a seal, while the fit between the lip and the mounting groove provides an anti-dislodgement function.

[0013] According to a second aspect of the present disclosure, the electric drive assembly includes an assembly housing and the oil seal structure described above, the assembly housing having a mounting hole for mounting a motor shaft, and the oil seal structure being embedded in the mounting hole.

[0014] According to a third aspect of the present disclosure, a vehicle is provided, the vehicle including the electric drive assembly described above.

[0015] By implementing the above technical solutions, without affecting the normal use of the oil seal structure, an anti-detachment design can be made on the assembly shell and the oil seal structure. This can effectively prevent the oil seal structure from detaching due to thermal expansion and contraction of the assembly shell, thereby improving the adaptability of the oil seal structure to complex working conditions and avoiding failure problems such as oil leakage caused by the detachment of the oil seal structure.

[0016] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings: Figure 1 This is an assembly cross-sectional view of the oil seal structure and the assembly housing provided in an exemplary embodiment of this disclosure; Figure 2 yes Figure 1 A magnified view of part A in the image; Figure 3 yes Figure 1 A magnified view of part B in the image.

[0018] Explanation of reference numerals in the attached figures 10-Assembly housing; 11-Mounting groove; 1-Frame; 2-Sealing body; 21-Lip; 211-Connecting part; 212-Locking part; 22-Gap. Detailed Implementation

[0019] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0020] In this disclosure, unless otherwise stated, "inner" and "outer" refer to the outline of the corresponding component itself. In this disclosure, when the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.

[0021] The electric drive assembly of a vehicle typically includes a motor, a reducer, a motor controller, and a mounting housing 10. The mounting housing 10 has a mounting hole for the motor shaft to pass through. In related technologies, oil seals are installed in the mounting hole via an interference fit. Rapid acceleration, rapid deceleration, and regenerative braking of electric vehicles generate huge torque shocks, which are transmitted to the reducer. At the same time, the vehicle's driving on bumpy roads also brings continuous vibration. Under long-term and severe vibration, a simple interference fit may loosen due to material fretting wear or fatigue. Furthermore, the oil seal is prone to loosening or complete detachment due to thermal expansion and contraction of the mounting housing 10. Once the oil seal detaches, it will cause a momentary and serious leak, which may trigger a chain of equipment failures and increase safety hazards.

[0022] To solve the above problems, refer to Figures 1 to 3 This disclosure provides an oil seal structure, which is installed in the aforementioned mounting hole. The oil seal structure may include a skeleton 1 and a sealing body 2. The skeleton 1 is made of metal such as low carbon steel or stainless steel, providing structural strength and rigidity to ensure that the oil seal structure can fit tightly with the assembly housing 10. The sealing body 2 is used for sealing connection with the assembly housing 10. The two are statically sealed, that is, there is no relative movement. The sealing body 2 also has a flexible lip for contacting the motor shaft. With the assistance of a spring, the lip gently wraps around the motor shaft with a certain interference fit. The lip and the motor shaft are dynamically sealed, that is, there is relative movement. The sealing body 2 has a lip 21 at its end, and the assembly housing 10 has a mounting groove 11. The lip 21 may include a connecting portion 211 and a locking portion 212 for engaging within the mounting groove 11. The connecting portion 211 is axially inclined from the sealing body 2 toward the frame 1, so that a gap 22 is formed between the connecting portion 211 and the assembly housing 10. The locking portion 212 is folded outward along the end of the connecting portion 211 into a barb shape. Accordingly, the lip 21 is elastic, and the material of the lip 21 may be nitrile rubber or fluororubber. Nitrile rubber has excellent oil resistance and good wear resistance, elasticity, and mechanical strength; fluororubber has excellent high temperature resistance and oil resistance.

[0023] During the press-fitting process, the oil seal structure generates stress, and the elastic lip 21 undergoes elastic deformation. During the press-fitting process, the locking part 212 can bend to abut against the connecting part 211, and the gap 22 disappears. Therefore, the design of the lip 21 will not affect the press-fitting process. After the oil seal structure is pressed into place, that is, when the locking part 212 moves to the mounting groove 11, the lip 21 will open up, that is, restore its elastic deformation. The locking part 212 can be tilted and locked in the mounting groove 11 to form an anti-dislodgement function.

[0024] By implementing the above technical solutions, without affecting the normal use of the oil seal structure, an anti-detachment design can be made on the assembly shell and the oil seal structure. This can effectively prevent the oil seal structure from detaching due to thermal expansion and contraction of the assembly shell, thereby improving the adaptability of the oil seal structure to complex working conditions and avoiding failure problems such as oil leakage caused by the detachment of the oil seal structure.

[0025] In embodiments of this disclosure, reference is made to Figure 3 The locking part 212 can partially extend into the mounting groove 11 to provide deformation space for the locking part 212 during press-fitting. The following is an example... Figure 3 To illustrate the press-fitting process: During the press-fitting process, the oil seal structure is installed axially into the mounting hole. During this process, the locking part 212 can undergo elastic deformation to close the gap 22 between the connecting part 211 and the assembly housing 10. After installation, the locking part 212 returns to its elastic deformation, and the part away from the connecting part 211 extends into the mounting groove 11 to achieve the function of preventing it from coming off.

[0026] In some embodiments, reference Figure 3 The intersection of the connecting part 211 and the locking part 212 is constructed with a rounded corner. Specifically, the intersection of the connecting part 211 and the locking part 212 on the side near the assembly housing 10 is constructed with a rounded corner. This configuration can significantly reduce stress concentration. The rounded corner provides a smooth and gradual transition channel for stress, allowing stress to be evenly distributed, thereby minimizing the stress concentration effect, extending the fatigue life of the sealing body 2, and enhancing the structural rigidity and stability.

[0027] Among them, reference Figure 3 The cross-section of the connecting portion 211 can be constructed as a cone, and the cross-section gradually decreases from the position near the sealing body 2 to the position near the locking portion 212, so as to achieve a smooth stress transition and reduce stress concentration. The cross-section of the connecting portion 211 can be constructed as a square or a cylinder, and this disclosure is not limited thereto.

[0028] According to some embodiments, the extending direction of the connecting portion 211 can be at an angle of 20° to 45° with the axial direction of the frame 1, specifically 25°, 30°, 35°, or 40°. Here, the extending direction of the connecting portion 211 can be understood as the direction of inclination of the connecting portion 211 toward the side of the assembly housing 10, as can be referred to... Figure 3 As shown by arrow a in the diagram. The connecting part 211 is tilted so that a gap 22 is formed between the connecting part 211 and the assembly housing 10, thereby providing space for the elastic deformation of the locking part 212 during the press-fitting process and avoiding affecting the press-fitting process.

[0029] Furthermore, the extending direction of the locking portion 212 can be at an angle of 30° to 60° with the axial direction of the frame 1, specifically 40° or 50°. It should be noted that the extending direction of the locking portion 212 can be interpreted as the inclination direction of the portion of the locking portion 212 that extends into the mounting groove 11, as shown in the reference... Figure 3 As shown by arrow b in the diagram, the inclined, hook-shaped locking portion 212 can better prevent the oil seal structure from coming off after it extends into the mounting groove 11.

[0030] In some embodiments, the lip 21 and the sealing body 2 can be integrally molded. This integral design eliminates weak points in the connection, making it robust, durable, and offering better sealing and aesthetics. Because there are no seams or connection points, the integral design is ideal for components requiring leak-proof construction, such as oil seals. In other embodiments, the lip 21 and the sealing body 2 can also be bonded or connected using other suitable methods.

[0031] In some embodiments, the sealing body 2 and the assembly housing 10 can be interference-fitted. The interference fit achieves a seal, and the engagement of the lip 21 with the mounting groove 11 provides an anti-dislodgement function. The interference fit structure is simple and compact, requiring no additional connecting parts. It relies on continuous static friction, possessing excellent dynamic performance and anti-loosening capabilities. The extremely high surface contact pressure effectively blocks minute leakage paths, facilitating the sealing function.

[0032] According to a second aspect of this disclosure, an electric drive assembly is also provided. This electric drive assembly may include a mounting housing 10 and the aforementioned oil seal structure. The mounting housing 10 has a mounting hole for mounting a motor shaft, and the oil seal structure is embedded within the mounting hole. This oil seal structure can resist pressure fluctuations, avoiding the risk of the oil seal being ejected due to increased internal pressure, ensuring the reliability of the seal, and effectively preventing the oil seal structure from detaching due to thermal expansion and contraction of the mounting housing. This improves the adaptability of the oil seal structure under complex working conditions and avoids failure problems such as oil leakage caused by the oil seal structure detaching. This electric drive assembly possesses all the beneficial effects of the aforementioned oil seal structure, which will not be elaborated further here.

[0033] According to a third aspect of this disclosure, a vehicle is also provided that may include the aforementioned electric drive assembly. All the advantages of having the aforementioned electric drive assembly and oil seal structure will not be elaborated here.

[0034] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0035] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0036] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. An oil seal structure, comprising a skeleton and a sealing body, the sealing body being used for a sealing connection with an assembly housing, characterized in that, The sealing body has a lip at its end, the lip being elastic, and an mounting groove is formed on the assembly housing. The lip includes a connecting portion and a locking portion for locking within the mounting groove. The connecting portion is axially inclined from the sealing body toward the skeleton to form a gap between the connecting portion and the assembly housing. The locking portion is folded outward along the end of the connecting portion in a hook shape.

2. The oil seal structure according to claim 1, characterized in that, The locking portion extends into the mounting groove.

3. The oil seal structure according to claim 1, characterized in that, The intersection of the connecting part and the locking part is constructed with rounded corners.

4. The oil seal structure according to claim 1, characterized in that, The cross-section of the connecting part is tapered.

5. The oil seal structure according to claim 1, characterized in that, The extension direction of the connecting part is at an angle of 20° to 45° with the axial direction of the skeleton.

6. The oil seal structure according to claim 1, characterized in that, The extension direction of the locking part is at an angle of 30° to 60° with the axial direction of the skeleton.

7. The oil seal structure according to claim 1, characterized in that, The lip is integrally formed with the sealing body.

8. The oil seal structure according to claim 1, characterized in that, The sealing body is interference-fitted with the assembly housing.

9. An electric drive assembly, characterized in that, The electric drive assembly includes an assembly housing and an oil seal structure according to any one of claims 1-8, the assembly housing having a mounting hole for mounting a motor shaft, and the oil seal structure being embedded in the mounting hole.

10. A vehicle, characterized in that, The vehicle includes the electric drive assembly as described in claim 9.

Images