Vehicle oil seal made of nitrile rubber material

Abstract

The utility model relates to the technical field of oil seals, in particular to a vehicle oil seal made of nitrile rubber materials, which comprises a rubber body, a framework, a spring and a sealing piece. The first bent part is formed by bending the framework from the axial direction parallel to the rubber body to the radial direction parallel to the rubber body, the second bent part is formed by bending the framework from the radial section of the framework to the main sealing lip, and a plurality of annular grooves are formed in the outer ring of the rubber body. Due to the fact that the second bending part is arranged, the strength of the waist portion of the main lip is improved, the anti-eccentricity capacity of the lip is improved, the shape retentivity of the oil seal is improved, the service life of the oil seal is prolonged, and the maintenance frequency is reduced. And the annular groove can accommodate the compressed rubber body and provide an elastic deformation space for the rubber body, so that the oil seal is firmly pressed, and the sealing effect is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of oil seals, in particular to a vehicle oil seal made of nitrile rubber. Background Art

[0002] As the country's urban and rural development improves, people have higher and higher requirements for the performance of automobiles. As a result, the sealing performance requirements for various automobile parts are getting higher and higher. Especially for engineering vehicles, such as pickup trucks, oil leakage at the rear axle hub is required to be strictly controlled. Oil stains are not allowed to pollute the road after leakage. The rear axle of the car is part of the vehicle's power transmission system. It distributes the power transmitted by the engine through the transmission system to the two rear wheels to enable the vehicle to move. The oil seal must have good sealing performance to prevent lubricating oil leakage and prevent external contaminants from entering the bearings and differentials. Nowadays, the service life of the rear axle half-shaft oil seal of the car is more stringent, requiring more than 3 years or more than 120,000 kilometers without oil leakage;

[0003] In the prior art, a Chinese utility model patent with publication number CN204852351U discloses a rubber oil seal with a secondary sealing lip attached to a polytetrafluoroethylene sheet, comprising a rubber body, a support frame, a spring, and a polytetrafluoroethylene sheet. The spring is fastened to the primary sealing lip, and the support frame is disposed within the rubber body. The polytetrafluoroethylene sheet is bonded to the rubber body, and the polytetrafluoroethylene sheet and the rubber body form a secondary sealing lip structure. The polytetrafluoroethylene sheet and the rubber body form an interference fit structure between the secondary sealing lip and the shaft, providing secondary sealing and dustproofing. The secondary sealing lip is made of polytetrafluoroethylene sheet, which is wear-resistant.

[0004] In view of the above-mentioned related technologies, the inventor believes that the following defects exist: the support frame is arranged in an L shape and adopts a bent support frame, which has poor structural rigidity. During use, the anti-eccentricity performance is weak, which makes the oil seal have low shape retention during use, affecting its service life. Secondly, the outer ring of the oil seal and the shaft hole are interference fit. After the rubber body is pressed into the shaft hole, there is no space to accommodate the compressed rubber, which will cause the oil seal to jump up under the elastic action of the rubber body after installation, thereby causing the oil seal to loosen, affecting the sealing effect, and at the same time, increasing the difficulty of installing the oil seal. Moreover, the spring is fastened to the main sealing lip by the elastic action of its inner ring, and there is a lack of support and limit for the spring. During use, after being vibrated, the spring is easily caused to slip, thereby affecting the sealing effect. In particular, when the oil seal is used on the rear axle half shaft of a car, the rear axle half shaft will be subjected to forces and vibrations from all directions under ever-changing road conditions. Utility Model Content

[0005] In order to solve at least one technical problem in the background technology, the present application provides a vehicle oil seal made of nitrile rubber material.

[0006] The utility model provides a vehicle oil seal made of nitrile rubber material adopts the following technical solution:

[0007] A vehicle oil seal made of nitrile rubber material includes a rubber body, a skeleton, a spring, and a seal. The skeleton is embedded in the rubber body. One end of the inner ring of the rubber body has a raised main sealing lip. The spring is fastened within the main sealing lip. The seal is connected to the other end of the rubber body and is bent toward the main sealing lip to form a secondary sealing lip. The skeleton is provided with a first bent portion and a second bent portion. The first bent portion is formed by bending the skeleton from an axial direction parallel to the rubber body to a radial direction parallel to the rubber body. The second bent portion is formed by bending from a radial section of the skeleton toward the main sealing lip. The outer ring of the rubber body is provided with a plurality of annular grooves, and the annular grooves are arranged corresponding to the axial section of the skeleton.

[0008] Preferably, the rubber body is provided with a groove for installing the spring, and the main sealing lip is provided with a protrusion protruding toward the axial section of the skeleton, and the protrusion is bent along the outer wall of the spring.

[0009] Preferably, an angle a is formed between the second bent portion and the radial section of the skeleton, and the angle a is 135°±5°.

[0010] Preferably, a positioning groove is formed at one end of the rubber body away from the sealing element, and the positioning groove is recessed from the rubber body toward the axial section of the skeleton.

[0011] Preferably, the main sealing lip is provided with a first inclined surface tilted from top to bottom, and the main sealing lip is provided with a second inclined surface tilted from bottom to top, and the intersection of the first inclined surface and the second inclined surface is located at the end of the spring axis away from the auxiliary sealing lip.

[0012] Preferably, an included angle b is formed between the first inclined surface and the secondary sealing lip, and the included angle b is 20°±10°. An included angle c is formed between the first inclined surface and the second inclined surface, and the included angle c is 115°±5°.

[0013] Preferably, the axial length of the secondary sealing lip is 32% to 65% of the axial length of the rubber body.

[0014] Preferably, a limiting groove is provided at one end of the rubber body close to the sealing member, and the limiting groove and the sealing member are spaced apart along the radial direction of the rubber body.

[0015] Preferably, a guide surface is provided at one end of the rubber body close to the positioning groove, and the guide surface is gradually inclined from the rubber body toward the annular groove.

[0016] Preferably, the sealing member is made of polytetrafluoroethylene.

[0017] The beneficial effects of the utility model are:

[0018] By providing a second bending portion, the waist strength of the main lip is increased, the lip's anti-eccentricity ability is improved, the shape retention of the oil seal is improved, the service life of the oil seal is increased, and the maintenance frequency is reduced. Secondly, by providing an annular groove, when the oil seal is assembled with the shaft hole, the annular groove can accommodate the compressed rubber body, providing elastic deformation space for the rubber body, so that the oil seal is pressed firmly and not prone to jumping, thereby improving the sealing effect and reducing the risk of oil seal loosening. At the same time, it reduces the height difference generated during assembly, and also plays a shock-absorbing role, reducing the impact of oil seal leakage caused by the tilt of the oil seal press-fitting. In addition, when the oil seal is in use, high and low temperature resistant lithium-based grease is applied around the main sealing lip. The oil seal plays a lubricating role during rotation and reduces wear.

[0019] By providing grooves, the positioning accuracy and stability of the spring are improved, which helps prevent the spring from moving or sliding during use. The design of the raised part further improves the assembly stability of the spring and the rubber body, making it suitable for use in scenarios where there is large vibration in the rear axle half shaft of the car. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a top perspective view of an oil seal in an embodiment of the present application;

[0021] Figure 2 yes Figure 1 sectional perspective view of

[0022] Figure 3 yes Figure 2 A partial enlarged view of point A in the middle;

[0023] Figure 4 is a bottom perspective view of an oil seal in an embodiment of the present application;

[0024] Figure 5 yes Figure 4 Center section main view;

[0025] Figure 6 This is a first partial enlarged view in the embodiment of the present application;

[0026] Figure 7 This is a second partial enlarged view in the embodiment of the present application;

[0027] Figure 8 Schematic diagram of the oil seal assembly in the embodiment of the present application.

[0028] Explanation of the accompanying drawings: 1. Rubber body; 101. Main sealing lip; 1011. Protrusion; 1012. First inclined surface; 1013. Second inclined surface; 102. Annular groove; 103. Groove; 104. Positioning groove; 105. Limiting groove; 106. Guide surface; 2. Skeleton; 201. First bending portion; 202. Second bending portion; 3. Spring; 4. Seal; 401. Secondary sealing lip. DETAILED DESCRIPTION

[0029] This section will describe the specific embodiments of the present application in detail. The preferred embodiments of the present application are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that each technical feature and the overall technical solution of the present application can be understood intuitively and vividly, but it cannot be understood as a limitation on the scope of protection of the present application.

[0030] In the description of this application, if there is a description of orientation, such as "upper", "lower", "front", "back", "left", "right", etc., the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings. It is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, it should not be understood as a limitation on this application. When a feature is referred to as being "disposed", "fixed", or "connected" to another feature, it can be directly disposed, fixed, or connected to the other feature, or indirectly disposed, fixed, or connected to the other feature.

[0031] In the description of this application, if the word "several" is mentioned, it means one or more; if the word "multiple" is mentioned, it means more than two; if the word "greater than," "less than," or "exceeds," it should be understood as excluding the number itself; if the word "above," "below," or "within" is mentioned, it should be understood as including the number itself. If the word "first" or "second" is mentioned, it should be understood as distinguishing technical features, and should not be understood as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0032] In addition, unless otherwise defined, the technical terms and scientific terms used in this application have the same meaning as those commonly understood by those skilled in the art. The terms used in this application are only for describing specific embodiments and are not intended to limit this application. It should be understood that when used in this specification and the appended claims, the terms "comprise" and "include" indicate the presence of the described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their collections.

[0033] Example: Figure 1-8As shown, a vehicle oil seal made of nitrile rubber material includes a rubber body 1, a skeleton 2, a spring 3, and a seal 4. The skeleton 2 is embedded in the rubber body 1. One end of the inner ring of the rubber body 1 has a main sealing lip 101 with a convex setting. The main sealing lip 101 is used to prevent leakage of the internal sealing medium. The spring 3 is fastened in the main sealing lip 101. The seal 4 is connected to the other end of the rubber body 1 and is bent toward the main sealing lip 101 to form a secondary sealing lip 401. The secondary sealing lip 401 is used to prevent external dust, muddy water, and foreign matter from entering the interior and prevent leakage of the internal sealing medium. The skeleton 2 is provided with a first bending portion 201, a second bending portion 202, and a third bending portion 204. Two bending portions 202, the first bending portion 201 is formed by bending the skeleton 2 from the axial direction parallel to the rubber body 1 to the radial direction parallel to the rubber body 1. The skeleton 2 is formed into an axial section and a radial section by being provided with the first bending portion 201. The radial section of the skeleton 2 refers to the part of the skeleton 2 parallel to the radial direction of the rubber body 1, and the axial section of the skeleton 2 is the part of the skeleton 2 parallel to the axis of the rubber body 1. The second bending portion 202 is formed by bending from the radial section of the skeleton 2 toward the main sealing lip 101. The outer ring of the rubber body 1 is provided with a plurality of annular grooves 102, and the annular grooves 102 are arranged corresponding to the axial section of the skeleton 2.

[0034] By providing a second bent portion 202, the waist strength of the main lip is increased, the lip's anti-eccentricity ability is improved, the shape retention of the oil seal is improved, the service life of the oil seal is improved, and the maintenance frequency is reduced. By providing an annular groove 102, when the oil seal is assembled with the shaft hole, the annular groove 102 can accommodate the compressed rubber body 1, providing elastic deformation space for the rubber body 1, so that the oil seal is pressed firmly and not prone to jumping up, thereby improving the sealing effect and reducing the risk of oil seal loosening. At the same time, it reduces the height difference generated during assembly and has a shock-absorbing effect, reducing the impact of oil seal leakage caused by the tilt of the oil seal press-fitting. In addition, when the oil seal is in use, high and low temperature resistant lithium-based grease is applied around the main sealing lip 101, and the oil seal plays a lubricating role during rotation, reducing wear.

[0035] Furthermore, in order to improve the assembly of the oil seal and accommodate the deformation of the rubber body 1, multiple groups of annular grooves 102 are provided, and the multiple groups of buffer grooves are equidistantly spaced along the axis of the rubber body 1. The axial distance between the multiple groups of annular grooves 102 is 36.3% to 85.7% of the axial length of the rubber body 1. In this embodiment, the axial length H of the rubber body 1 is 7 to 11 mm, and the axial distance between the multiple groups of annular grooves 102 is 4 to 6 mm. Preferably, the axial length of the rubber body 1 is 11 mm, and the axial distance between the multiple groups of annular grooves 102 is 6 mm.

[0036] In order to improve the stability of the installation of the spring 3, enhance the supporting and limiting effect of the spring 3, and reduce the risk of the spring 3 slipping off after the oil seal is vibrated during use, the rubber body 1 is provided with a groove 103 for installing the spring 3, and the main sealing lip 101 is provided with a protrusion 1011 protruding toward the axial section of the skeleton 2. The protrusion 1011 is bent along the outer wall of the spring 3. By providing the groove 103, the positioning accuracy and stability of the spring 3 are improved, which helps to prevent the spring 3 from moving or sliding during use. The design of the protrusion 1011 further improves the assembly stability of the spring 3 and the rubber body 1, thereby being suitable for use scenarios where the rear axle half-axle of the automobile has large vibration.

[0037] Furthermore, the arc length angle formed by the protrusion 1011 and the inner wall of the groove 103 is greater than 180°, thereby preventing the spring 3 from slipping during use.

[0038] Reference Figure 6 and Figure 7 The first bend is a right-angle bend, and an arc-shaped transition is adopted at the bend to reduce stress concentration. In terms of the specific bending angle of the second bend portion 202, an angle a is formed between the second bend portion 202 and the radial section of the skeleton 2, and the angle a is 135°±5°. Preferably, the angle a is 135°, which improves the strength and durability of the supporting skeleton 2 and reduces fatigue damage at the bend, thereby extending the service life of the oil seal and reducing the risk of oil seal failure due to stress concentration. Through the design of the angle a, the support of the skeleton 2 to the main sealing lip 101 is optimized, and the strength of the waist of the main lip is enhanced, so that the oil seal can maintain better shape retention when subjected to external vibration and impact, thereby improving the seismic performance of the oil seal and reducing the risk of sealing failure due to vibration.

[0039] In order to axially position the skeleton 2, a positioning groove 104 is provided at one end of the rubber body 1 away from the seal 4. The positioning groove 104 is recessed from the rubber body 1 toward the axial section of the skeleton 2. The radial width of the positioning groove 104 is smaller than the radial width of the radial section of the skeleton 2, thereby positioning the height of the skeleton 2, that is, positioning the axial direction of the skeleton 2, thereby reducing the assembly error of the skeleton 2 during the vulcanization process.

[0040] It is worth mentioning that the axial direction and radial direction mentioned in this embodiment are relative to the rubber body 1 , the direction parallel to the axis of the rubber body 1 is the axial direction, and the direction parallel to the diameter of the rubber body 1 is the radial direction.

[0041] Reference Figure 6 and Figure 7In terms of the specific structure of the main sealing lip 101, the main sealing lip 101 is provided with a first inclined surface 1012 tilted downward from the top, and a second inclined surface 1013 tilted upward from the bottom. The intersection of the first inclined surface 1012 and the second inclined surface 1013 is located at the end of the spring 3 axis away from the secondary sealing lip 401, that is, the intersection of the first inclined surface 1012 and the second inclined surface 1013 is located below the axis of the spring 3, so that the spring 3 can better adapt to the dynamic changes of the outer wall of the shaft when the force is applied. When the first bevel 1012 and the second bevel 1013 intersect below the axis of the spring 3, the sealing lip can maintain good contact pressure when subjected to vibration or axial force, reducing the risk of sealing failure. Secondly, the main sealing lip 101 is provided with the second bevel 1013, which can better prevent internal sealing medium leakage. The main sealing lip 101 is provided with the first bevel 1012, which provides bending space for the bending of the seal 4 to form a longer secondary sealing lip 401, thereby optimizing the sealing performance of the oil seal.

[0042] The distance between the intersection of the first inclined surface 1012 and the second inclined surface 1013 and the end of the rubber body 1 away from the sealing member 4 is 1.0 to 1.5 mm.

[0043] Reference Figure 6 and Figure 7 In terms of the specific angle design of the first inclined surface 1012 and the second inclined surface 1013, an angle b is formed between the first inclined surface 1012 and the secondary sealing lip 401, and the angle b is 20°±10°. Preferably, the angle b is 20°, and an angle c is formed between the first inclined surface 1012 and the second inclined surface 1013, and the angle c is 115°±5°. Preferably, the angle c is

[0044] 115°, so as to better adapt to the force of the spring 3. When the oil seal is installed, the main sealing lip 101 is pressed against the outer wall of the shaft under the elastic force of the spring 3, and the design of the angle b provides bending space for the bending of the seal 4 to form a longer secondary sealing lip 401.

[0045] In terms of the specific radial strip structure design of the secondary sealing lip 401, the axial length of the secondary sealing lip 401 is 32% to 65% of the axial length of the rubber body 1. Preferably, the axial length of the secondary sealing lip 401 is 65% of the axial length of the rubber body 1. By lengthening the axial length of the secondary sealing lip 401, the contact area between the secondary sealing lip 401 and the shaft is increased, thereby improving the sealing effect, ensuring that external dust, muddy water, and foreign matter are prevented from entering the interior, and preventing leakage of internal sealing medium.

[0046] In this embodiment, the axial length of the rubber body 1 is 7-11 mm, and the axial length of the secondary sealing lip 401 is 4±0.5 mm. Preferably, the axial length of the rubber body 1 is less than 11 mm, and the axial length of the secondary sealing lip 401 is less than 4.5 mm.

[0047] In order to limit the radial direction of the seal 4 and to cushion the seal 4 during use, a limiting groove 105 is provided at one end of the rubber body 1 close to the seal 4. The limiting groove 105 and the seal 4 are spaced apart along the radial direction of the rubber body 1, which provides a certain buffer space for the sealing system. During use, the limiting groove 105 can absorb and disperse external shocks and vibrations to a certain extent, thereby enhancing the overall reliability of the sealing system and reducing the risk of sealing failure due to vibration.

[0048] Reference Figure 6 and Figure 7 In order to facilitate the assembly of the oil seal, a guide surface 106 is provided at one end of the rubber body 1 close to the positioning groove 104. The guide surface 106 is gradually inclined from the rubber body 1 toward the annular groove 102. An angle d is formed between the guide surface 106 and the outer ring of the rubber body 1. The angle d is 20±10°. Preferably, the angle d is 20°. The provision of the guide inclined surface plays a guiding and positioning role when the oil seal is assembled. When the oil seal is in use, the outer ring of the oil seal is assembled with the inner hole of the oil seal at the rear axle of the automobile to form a sealing unit, and the inner ring of the oil seal is assembled with the rear axle half shaft to form a sealing unit.

[0049] Among them, the seal 4 is made of polytetrafluoroethylene, and the rubber body 1 is made of nitrile rubber with good wear resistance, high tear resistance and excellent resistance to mineral oil in the existing technology. The rubber body 1 is mainly composed of nitrile rubber material, and is filled with wear-resistant material. By optimizing the design formula, a high-performance nitrile rubber with lower friction coefficient, stronger wear resistance, higher tear resistance and wide temperature resistance is designed. The temperature range of the high-performance nitrile rubber seal is 42°C to 125°C. The high-performance nitrile rubber is an existing technology and will not be described in detail here. It is beneficial to prevent the rubber from aging and leaking during relative operation of the oil seal, and can meet the use requirements of automobile oil seal sealing shafts, especially the use requirements of the rear axle half-axle oil seal sealing shafts of pickup trucks.

[0050] It is worth mentioning that the oil seal is suitable for sealing the rear axle half-axle of a car. During the oil seal processing, the seal 4, rubber, and skeleton 2 are vulcanized and assembled together, and then the spring 3 is installed on the groove 103. The skeleton 2 mainly plays the function of fixing the sealing hole. The seal 4 made of polytetrafluoroethylene mainly plays the function of sealing and sealing the half-axle. The rubber body 1 mainly plays the function of sealing oil. The main sealing lip 101 is assembled to the sealing shaft and produces an interference fit with the sealing shaft to play a sealing role. A closed cavity is formed between the main sealing lip 101 and the skeleton 2 to ensure that the oil seal lip has a radial force on the sealing shaft, and can produce relative motion function after vulcanization.

[0051] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present application, and such modifications or substitutions should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A vehicle oil seal made of nitrile rubber, comprising a rubber body, a frame, a spring, and a sealing member, wherein the frame is embedded in the rubber body, one end of the inner ring of the rubber body has a raised primary sealing lip, the spring is fastened within the primary sealing lip, and the sealing member is connected to the other end of the rubber body and is bent toward the primary sealing lip to form a secondary sealing lip, characterized in that: The skeleton is provided with a first bending portion and a second bending portion. The first bending portion is formed by bending the skeleton from an axial direction parallel to the rubber body to a radial direction parallel to the rubber body. The second bending portion is formed by bending from the radial section of the skeleton toward the main sealing lip. The outer ring of the rubber body is provided with a plurality of annular grooves, and the annular grooves are provided corresponding to the axial section of the skeleton. The rubber body is provided with a groove for mounting the spring. The main sealing lip is provided with a protrusion protruding toward the axial section of the skeleton, and the protrusion is bent along the outer wall of the spring. The main sealing lip is provided with a first inclined surface inclined from top to bottom, and the main sealing lip is provided with a second inclined surface inclined from bottom to top. The intersection of the first inclined surface and the second inclined surface is located at the end of the spring axis away from the secondary sealing lip.

2. The vehicle oil seal made of nitrile rubber material according to claim 1, characterized in that: The annular grooves are provided in multiple groups, and the multiple groups of annular grooves are arranged at equal intervals along the axis of the rubber body.

3. The vehicle oil seal made of nitrile rubber material according to claim 1, characterized in that: An angle a is formed between the second bending portion and the radial section of the skeleton, and the angle a is 135°±5°.

4. The vehicle oil seal made of nitrile rubber material according to claim 1, characterized in that: A positioning groove is formed on one end of the rubber body away from the sealing component. The positioning groove is recessed from the rubber body toward the axial section of the skeleton.

5. The vehicle oil seal made of nitrile rubber material according to claim 1, characterized in that: An included angle b is formed between the first inclined surface and the auxiliary sealing lip, and the included angle b is 20°±10°. An included angle c is formed between the first inclined surface and the second inclined surface, and the included angle c is 115°±5°.

6. The vehicle oil seal made of nitrile rubber material according to claim 1, characterized in that: The axial length of the secondary sealing lip is 32% to 65% of the axial length of the rubber body.

7. The vehicle oil seal made of nitrile rubber material according to claim 1, characterized in that: A limiting groove is provided at one end of the rubber body close to the sealing member, and the limiting groove and the sealing member are spaced apart along the radial direction of the rubber body.

8. The vehicle oil seal made of nitrile rubber material according to claim 4, characterized in that: A guide surface is provided on one end of the rubber body close to the positioning groove, and the guide surface is gradually inclined from the rubber body toward the annular groove.

9. The vehicle oil seal made of nitrile rubber material according to claim 8, characterized in that: An included angle d is formed between the guide surface and the outer ring of the rubber body, and the included angle d is 20±10°.

10. The vehicle oil seal made of nitrile rubber material according to claim 1, characterized in that: The sealing element is made of polytetrafluoroethylene.

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