Ball pin with double-sealing structure, suspension system and automobile

Abstract

The invention relates to the technical field of ball pin assembly, in particular to a ball pin with a double-sealing structure, a suspension system and an automobile, the ball pin comprises a ball pin rod, a ball pin seat and a ball pin sleeve, the spherical end of the ball pin rod is pressed into a spherical inner cavity of the ball pin seat, the ball pin seat is pressed into the ball pin sleeve, the bottom of the ball pin sleeve is open, and the ball pin sleeve is arranged in the spherical inner cavity of the ball pin seat. The bottom of the ball pin sleeve is further connected with a protective sleeve in a clamped mode, the protective sleeve is used for sealing the opening in the bottom of the ball pin sleeve, the top face of the protective sleeve abuts against the rubber end cover, the rubber end cover is in interference fit with the opening in the bottom of the ball pin sleeve, first-stage sealing is achieved, the rubber end cover is pressed tightly through the protective sleeve, and the ball pin base is sealed through the rubber end cover. The second-stage sealing is realized; the air tightness and the anti-corrosion performance of the attached position of the ball pin sleeve and the rubber end cover are improved through a double-sealing structure; compared with a traditional riveting end cover process, the sealing performance and the anti-corrosion performance of the ball pin are remarkably improved through a double-sealing structure composed of the rubber end cover and the plastic protective sleeve.

Description

Technical Field

[0001] The invention relates to the technical field of ball pin assembly, in particular to a ball pin with a double sealing structure, a suspension system and an automobile. Background Art

[0002] The industry's primary process for assembling end caps in ball pin assemblies is riveting. This process involves applying axial pressure and torsional loads to the workpiece through a rotating rivet head, causing controlled plastic flow in the material and forming a permanent mechanical connection. The rear end cap is secured to the lower end of the ball pin sleeve and acts as a seal. The riveting process achieves fastening by deforming the metal through rotational pressure and torsional loads. However, during the riveting process, significant mechanical scratches often form at the riveted joint due to the intense friction between the ball pin sleeve and the edge of the end cap. These surface defects can disrupt the continuity of the metal matrix, leading to the following issues: 1. Decreased anti-corrosion performance: The scratch marks produced by riveting the end cover and the ball pin sleeve are prone to form the starting point of electrochemical corrosion. In the salt spray test, the rust rate is 3-5 times faster than that of the intact area; 2. Stress concentration risk: Sharp scratches may become the source of fatigue cracks, reducing the service life of the ball pin; 3. Impact on sealing: Irregular surfaces will weaken the fit between the end cover and the ball pin sleeve, reducing the airtightness of the ball pin. Summary of the Invention

[0003] In response to the shortcomings of the existing technology, the purpose of the present invention is to provide a double-sealed structure ball pin, suspension system and automobile, which improves the air tightness and corrosion resistance of the joint between the ball pin sleeve and the rubber end cover through the double-sealed structure; compared with the traditional riveted end cover process, the double-sealed structure composed of the rubber end cover and the plastic protective cover significantly improves the sealing performance and corrosion resistance of the ball pin.

[0004] In order to achieve the above object, the present invention is implemented through the following technical solutions: The first aspect is a double-sealed ball pin, comprising a ball pin rod, a ball pin seat and a ball pin sleeve, wherein the spherical end of the ball pin rod is pressed into the spherical inner cavity of the ball pin seat, and the ball pin seat is pressed into the ball pin sleeve. The bottom of the ball pin sleeve is open, and a rubber end cover is installed at the opening to isolate the ball pin seat from the external environment. A protective cover is also clamped at the bottom of the ball pin sleeve, and the protective cover is used to seal the bottom opening of the ball pin sleeve, and the top surface of the protective cover abuts the rubber end cover. The double-sealed structure composed of the rubber end cover and the plastic protective cover significantly improves the sealing performance and corrosion resistance of the ball pin.

[0005] As a further implementation method, an annular groove is provided on the inner side of the bottom end of the ball pin sleeve, and the rubber end cover is installed in the annular groove, and the rubber end cover and the bottom end of the ball pin sleeve are interference fit.

[0006] As a further implementation method, the protective cover includes a bottom plate and side walls connected to the sides of the bottom plate. A circle of snap-fit structure is provided on the top of the side wall. The snap-fit structure is used to cooperate with the slot on the outside of the bottom of the ball pin sleeve. The bottom plate is used to press the rubber end cover.

[0007] As a further implementation, the side wall of the protective cover is arranged in a ring shape, and the buckle structure is arranged in a wave form.

[0008] As a further implementation method, a dust cover is also installed around the ball stud rod.

[0009] As a further implementation method, the bottom end of the dust cover is fixed to the slot at the top of the ball pin sleeve by a lower retaining spring, and an upper retaining spring is provided on the inner side of the top end of the dust cover.

[0010] As a further implementation method, a cone ring is further provided on the peripheral side of the ball stud rod at the top of the dust cover.

[0011] As a further implementation, a circular protrusion is provided on the bottom plate of the protective sleeve, and the circular protrusion is adapted to the shape of the bottom opening of the ball pin, and the protective sleeve presses the rubber end cover through the circular protrusion.

[0012] In a second aspect, a suspension system includes a double-sealed structure ball pin as described above, wherein the top end of the ball pin rod on the double-sealed structure ball pin is used to connect to the steering knuckle, and the ball pin sleeve is provided with a connecting end for connecting to the front swing arm.

[0013] A third aspect provides a vehicle equipped with the suspension system described above.

[0014] The beneficial effects of the present invention are as follows: 1. The present invention utilizes the interference fit between the rubber end cover and the bottom opening of the ball pin sleeve to achieve the first level of sealing, and utilizes the protective sleeve to compress the rubber end cover to achieve the second level of sealing. The protective sleeve can effectively protect the rubber end cover from external mechanical damage, and at the same time prevent external foreign matter from directly contacting the rubber end cover, thereby extending the service life of the rubber end cover and improving the sealing performance and reliability of the entire ball pin; the double sealing structure is used to improve the air tightness and corrosion resistance of the joint between the ball pin sleeve and the rubber end cover; compared with the traditional riveted end cover process, the double sealing structure composed of the rubber end cover and the plastic protective sleeve significantly improves the sealing performance and corrosion resistance of the ball pin.

[0015] 2. The buckle structure of the protective cover of this invention is arranged in a wavy pattern. This design not only ensures a secure connection but also provides a certain degree of elasticity. When the ball pin is subjected to a certain degree of impact or vibration, it can absorb some of the energy, reduce damage to the buckle connection, and improve the reliability of the connection between the protective cover and the ball pin sleeve. The peaks and troughs of the wavy buckle structure work together to increase the buckle area and enhance the connection strength, making the protective cover less likely to loosen during use and ensuring the long-term stability and effectiveness of the double-seal structure.

[0016] 3. The circular protrusion on the protective cover of the present invention is adapted to the shape of the opening at the bottom of the ball pin. The protective cover presses the rubber end cover through the circular protrusion, so that the space at the bottom of the rubber end cover is completely filled, achieving complete sealing; this circular protrusion design can effectively prevent the sealing performance from being degraded due to long-term pressure deformation of the rubber end cover, thereby improving the reliability and durability of the entire double sealing structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0018] Figure 1 This is a schematic diagram of the overall structure of a ball pin with a double sealing structure according to an embodiment of the present invention; Figure 2 2 is a schematic cross-sectional view of a ball pin with a double sealing structure according to an embodiment of the present invention; Figure 3 2 is a schematic diagram of the overall structure of the protective cover in an embodiment of the present invention.

[0019] In the figure: the distances or sizes between parts are exaggerated to show the positions of various parts, and the schematic diagram is for reference only.

[0020] Among them: 1. Ball pin rod; 11. Annular protrusion; 2. Conical ring; 3. Dust cover; 4. Built-in upper retaining spring; 5. Lower retaining spring; 6. Ball pin sleeve; 7. Ball pin seat; 8. Rubber end cover; 9. Protective cover; 61. Fixed end; 611. Annular groove; 612. Snap groove; 62. Connecting end; 91. Buckle. DETAILED DESCRIPTION

[0021] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those skilled in the art to which the present invention belongs.

[0022] Example 1 In a typical embodiment of the present invention, referring to Figure 1-Figure 3As shown, a double-sealed structure ball pin includes a ball pin rod 1, a ball pin seat 7 and a ball pin sleeve 6. The spherical end of the ball pin rod 1 is pressed into the spherical inner cavity of the ball pin seat 7, and the ball pin seat 7 is pressed into the ball pin sleeve 6. The bottom of the ball pin sleeve 6 is open, and a rubber end cover 8 is installed at the opening to isolate the ball pin seat 7 from the external environment. A protective sleeve 9 is also clamped at the bottom of the ball pin sleeve 6. The protective sleeve 9 is used to seal the bottom opening of the ball pin sleeve 6, and the top surface of the protective sleeve 9 abuts the rubber end cover 8.

[0023] This embodiment significantly improves the sealing performance and anti-corrosion performance of the ball pin through the double sealing structure composed of the rubber end cover 8 and the protective sleeve 9.

[0024] like Figure 1 and Figure 2 As shown, the ball pin sleeve 6 includes a connected fixed end 61 and a connecting end 62. The fixed end 61 is a hollow cylindrical structure as a whole. The ball pin seat 7 is pressed into the fixed end 61. The connecting end 62 serves as a cantilever structure with a mounting hole provided thereon. The ball pin sleeve 6 is connected to the front swing arm through the connecting end 62.

[0025] The ball pin seat 7 has a spherical inner cavity, and the lower end of the ball pin rod 1 is a spherical structure, which is pressed into the spherical inner cavity of the ball pin seat 7 by press-fitting.

[0026] The ball stud rod 1 is made of high-strength alloy steel, with a spherical head and a finely ground surface to ensure a perfect fit within the ball stud seat. The rod's threaded section allows for threaded connection to the steering knuckle or other related components, ensuring a secure and reliable connection. The strength and precision of the ball stud rod directly impact its overall performance. In actual production, precise heat treatment processes ensure excellent fatigue and wear resistance, enabling it to withstand the complex forces of vehicle operation and ensure safe driving.

[0027] The inner surface of the ball stud seat 7 is precision machined to a low roughness, ensuring a tight fit with the spherical end of the ball stud rod. Made of high-quality steel, the ball stud seat possesses sufficient strength and rigidity to effectively transmit force and motion. Lubrication grooves are designed into the mating area between the ball stud seat and the ball stud rod to ensure even distribution of lubricant across the contact surface, reducing friction and wear and increasing service life. The outer side of the ball stud seat mates with the ball stud sleeve and is secured by a press fit, ensuring a tight and stable connection.

[0028] Specifically, after the ball pin seat 7 is pressed into the fixed end 61 of the ball pin sleeve 6, the bottom end of the ball pin seat 7 is higher than the bottom end of the fixed end 61. The cross-section of the ball pin seat 7 is circular, and a circular groove is formed between the bottom of the ball pin seat 7 and the bottom end of the fixed end 61. The fixed end 61 is provided with an annular groove 611 on the inner side of the groove, and the rubber end cover 8 is installed in the annular groove 611, so that the rubber end cover 8 and the bottom end of the ball pin sleeve 6 are interference fit.

[0029] The rubber end cap 8 is the first sealing barrier in the double sealing structure. During the installation process, first place the rubber end cap 8 into the annular groove 611 on the inner side of the bottom end of the ball pin sleeve 6. Since the rubber end cap 8 and the bottom end of the ball pin sleeve 6 are interference fit, it is necessary to use a special installation tool, such as a rubber hammer or a press, to gently tap the rubber end cap 8 so that it is evenly embedded in the annular groove 611, ensuring that it fits tightly with the ball pin sleeve 6 without leaving any gaps. The material of the rubber end cap 8 is oil-resistant rubber, which has good elasticity and aging resistance. It can maintain a good sealing effect during long-term use, effectively blocking external dust, mud, water and pollutants from entering the interior of the ball pin, and also preventing the leakage of internal lubricating grease.

[0030] like Figure 3 As shown, the protective cover 9 includes a circular bottom plate and an annular side wall connected to the circumference of the bottom plate, and a circle of buckle 91 structure is provided on the top of the side wall.

[0031] A circle of slots is provided around the bottom of the fixed end 61 of the ball pin sleeve 6. A snap 91 engages with the slots on the outside of the bottom of the ball pin sleeve, allowing the protective sleeve 9 to be mounted on the bottom of the rubber end cap 8. The bottom plate of the protective sleeve 9 is used to press the rubber end cap tightly. The protective sleeve 9 and the rubber end cap 8 form a double seal structure.

[0032] like Figure 3 As shown, the sidewall of the protective sleeve 9 is annular, and the snap-fit structure extends in a wavy pattern. This wavy design ensures a secure connection while also providing a certain degree of elasticity. This design absorbs some of the energy from impact or vibration to the ball pin, mitigating damage to the snap-fit area and improving the reliability of the connection between the protective sleeve 9 and the ball pin sleeve 6. The peaks and troughs of the wavy snap-fit structure 91 interact with each other, increasing the snap-fit area and strengthening the connection. This prevents the protective sleeve 9 from loosening during use, ensuring the long-term stability and effectiveness of the dual-seal structure.

[0033] Furthermore, the top surface of the bottom plate of the protective cover 9 is provided with a circular protrusion that matches the shape of the opening at the bottom of the ball pin. The protective cover 9 compresses the rubber end cap with the circular protrusion, completely filling the space at the bottom of the rubber end cap and achieving a complete seal. In this embodiment, the protective cover 9 is made of plastic. The circular protrusion can be made of rubber material.

[0034] After the protective sleeve 9 is installed, the circular protrusion fits snugly against the bottom opening of the ball pin, further compressing the rubber end cap, ensuring closer contact between the rubber end cap 8 and the bottom end of the ball pin sleeve 6, thereby enhancing the sealing effect. The shape and size of the circular protrusion are precisely calculated and designed to ensure excellent sealing performance without increasing excessive assembly force. In actual application, this circular protrusion design effectively prevents the degradation of sealing performance caused by long-term compressive deformation of the rubber end cap 8, thereby improving the reliability and durability of the entire dual-seal structure.

[0035] It can be understood that the ball pin sleeve 6 of this embodiment serves as the outer shell of the entire ball pin, protecting the internal components and providing an installation interface. A rubber end cap 8 is installed at the bottom opening to isolate the ball pin seat from the external environment. The ball pin sleeve is made of corrosion-resistant, high-strength materials to adapt to various harsh environmental conditions during vehicle driving. An annular groove is provided on the inner side of the bottom of the ball pin sleeve, and the rubber end cap is installed in the annular groove and has an interference fit with the bottom end of the ball pin sleeve 6. This design ensures the stable installation position of the rubber end cap 8 in the ball pin sleeve 6, effectively preventing the rubber end cap 8 from loosening or falling off due to vibration or impact, thereby ensuring the long-term effectiveness of the sealing performance. A card slot is provided on the outside of the ball pin sleeve 6 for cooperating with the buckle 91 structure of the protective sleeve 9 to achieve a firm installation of the protective sleeve 9.

[0036] The bottom plate of the protective sleeve 9 is used to compress the rubber end cap 8, further enhancing the sealing effect. The protective sleeve 9 is made of engineering plastic with high strength and rigidity. It can effectively protect the rubber end cap 8 from external mechanical damage and prevent foreign matter from directly contacting the rubber end cap, thereby extending the service life of the rubber end cap 8 and improving the sealing performance and reliability of the entire ball pin.

[0037] like Figure 1 and Figure 2 As shown, a dust cover 3 is also mounted around the ball pin 1. The bottom end of the dust cover 3 is secured to the retaining groove 612 at the top of the fixed end 61 of the ball pin sleeve 6 via a lower retaining spring 5. The retaining spring 5 seals the bottom end of the dust cover 3 with the ball pin 1. An internal upper retaining spring 4 is located on the inner side of the top end of the dust cover. This internal upper retaining spring 4 engages with the annular protrusion 11 of the ball pin 1 to seal the top end of the dust cover with the ball pin 1. The use of the internal upper retaining spring 4 significantly enhances the stability of the dust cover and the sealing performance of the upper end of the dust cover.

[0038] A tapered ring 2 is also provided around the ball stud rod at the top of the dust cover. The lower end of the tapered ring 2 contacts the top of the dust cover 3. The provision of the tapered ring 2 increases the contact area and angle between the ball stud and the steering knuckle in the dual-seal structure, significantly reducing the risk of the ball stud seat collapsing.

[0039] The tapered ring's conical shape guides the distribution of lubricant, ensuring a more even application across the contact surface between the ball stud and the dust cover, reducing friction and wear and increasing the dust cover's service life. Made from the same material as the ball stud, the ring offers excellent strength and hardness, capable of withstanding axial and radial forces, ensuring stability and reliability during vehicle operation. The ring's precise mounting position ensures a tight fit with the top of the dust cover, further enhancing the seal.

[0040] This embodiment improves the air tightness and corrosion resistance of the joint between the ball pin sleeve 7 and the rubber end cover 8 through a double sealing structure, reducing the incidence of after-sales problems such as grease oxidation inside the ball pin, rust on the ball pin end cover, and intrusion of external pollutants.

[0041] The optional rubber end caps are made of 2-3mm thick EPDM9 (ethylene propylene diene monomer), which is highly resistant to corrosion by most acids, bases, and other chemicals, preventing deformation or damage. The EPDM rubber on the outer ring of the rubber end cap forms a primary seal with the annular groove at the fixed end of the ball pin sleeve, while a plastic protective sleeve forms a secondary seal.

[0042] Compared with the traditional riveting end cover process, the present invention significantly improves the sealing performance and anti-corrosion performance of the ball pin through the double sealing structure composed of the rubber end cover and the plastic protective sleeve.

[0043] This embodiment has been verified to reduce the ball pin's leakage rate from 0.15 cm³ / min to 0.03 cm³ / min (test pressure 0.3 MPa). It also improves the ball pin's dustproof rating from IP5K7 to IP6K9K (ISO 20653 standard). It also extends the ball pin's neutral salt spray test duration from 96 hours to 500 hours without corrosion.

[0044] The specific assembly steps are as follows: 1. Assemble the material on the line and add oil to the ball pin seat 7.

[0045] 2. The automatic press-fitting machine presses the ball pin rod 1 into the ball pin seat 7. During the press-fitting process, the sensor monitors the pressing force and displacement. If the pressing force and displacement exceed the limit, the assembly line alarms and shuts down.

[0046] 3. Press the assembled ball pin rod 1 and ball pin seat 7 into the fixed end 61 of the ball pin sleeve 6, and also perform press-fit monitoring.

[0047] 4. The automatic assembly machine installs the rubber end cover 8. Compared with the traditional riveting process, there are no riveting scratches at the interface between the rubber end cover 8 and the ball pin sleeve, and the EPDM rubber outside the rubber end cover can ensure air tightness.

[0048] 5. The laser marking machine prints the product logo on the rubber end cap 8.

[0049] 6. The dust cover 3 assembly machine assembles the dust cover 3.

[0050] 9. The circlip assembly machine assembles the lower circlip 5.

[0051] 10. The cone ring assembly machine presses the cone ring and monitors the press-fitting.

[0052] 11. The plastic protective cover 9 assembly machine assembles the plastic protective cover. Compared with the traditional ball pin, the invention adds a plastic protective cover 9, which is assembled to the lower part of the ball pin sleeve by snap-fitting. The plastic ball pin sleeve significantly improves the corrosion resistance, stone impact resistance, and air tightness of the lower part of the ball pin.

[0053] Example 2 In a typical embodiment of the present invention, referring to Figure 1-Figure 3 A suspension system is shown, comprising the double-seal ball stud described in Example 1. The top end of the ball stud rod 1 on the double-seal ball stud is used to connect to the steering knuckle. During installation, the threaded section at the top of the ball stud rod is aligned with the threaded hole in the steering knuckle. A dedicated tool is then used to screw the ball stud rod into the steering knuckle to ensure a secure and reliable connection. The ball stud sleeve also has a connecting end for connecting to the front swing arm.

[0054] The ball stud sleeve has mounting holes at its connection end, allowing bolts or pins to connect it to the front swing arm, ensuring stable connection and force transmission between the various components in the suspension system. During installation, the installation torque and position must be strictly controlled to ensure proper function and long-term stability of the ball stud in the suspension system.

[0055] In the automotive industry, particularly in suspension systems, ball pins are key connecting components whose performance and sealing properties crucially impact vehicle stability, safety, and service life. The innovative design of the double-seal ball pin disclosed in this invention effectively enhances its sealing performance, preventing the ingress of foreign matter and moisture while ensuring the stable retention of internal lubricating grease. This significantly extends the ball pin's service life and provides a strong guarantee for the reliable operation of automotive suspension systems.

[0056] Example 3 In a typical embodiment of the present invention, referring to Figure 1-Figure 3 As shown, a vehicle is provided with the suspension system described in Example 2. Through reasonable system integration and optimized design, the double-sealed ball pin can fully utilize its advantages, improve the reliability and durability of the vehicle, reduce maintenance costs, and enhance the vehicle's competitiveness in the market.

[0057] In practical applications, vehicles equipped with dual-seal ball pins demonstrate improved driving stability and reliability. The excellent sealing performance of the ball pin reduces driving anomalies such as steering wheel shake and swerving caused by ball pin failure, thereby improving driving comfort and safety. Furthermore, the extended ball pin lifespan reduces vehicle maintenance costs and downtime, improving vehicle efficiency and affordability. Field testing and user feedback confirm that vehicles equipped with dual-seal ball pins perform better in a variety of road conditions and environments, earning widespread recognition from the market and users.

[0058] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A double-seal structure ball pin, characterized in that: It includes a ball pin rod, a ball pin seat and a ball pin sleeve. The spherical end of the ball pin rod is pressed into the spherical inner cavity of the ball pin seat, and the ball pin seat is pressed into the ball pin sleeve. The bottom of the ball pin sleeve is open, and a rubber end cover is installed at the opening to isolate the ball pin seat from the external environment. A protective sleeve is also clamped at the bottom of the ball pin sleeve. The protective sleeve is used to seal the bottom opening of the ball pin sleeve, and the top surface of the protective sleeve abuts the rubber end cover.

2. A double-seal ball pin according to claim 1, characterized in that: An annular groove is provided on the inner side of the bottom end of the ball pin sleeve, and the rubber end cover is installed in the annular groove, and the rubber end cover and the bottom end of the ball pin sleeve are in interference fit.

3. A double-seal structure ball pin according to claim 2, characterized in that: The protective cover includes a bottom plate and side walls connected to the sides of the bottom plate. A circle of snap-fit structures is provided on the top of the side walls. The snap-fit structures are used to cooperate with the slots on the outside of the bottom of the ball pin sleeve. The bottom plate is used to press the rubber end cover.

4. A double-seal structure ball pin according to claim 3, characterized in that: The side wall of the protective cover is arranged in a ring shape, and the buckle structure is arranged in a wave form.

5. The double-seal structure ball pin according to claim 1, characterized in that: A dust cover is also installed around the ball stud rod.

6. A ball pin with a double sealing structure according to claim 5, characterized in that: The bottom end of the dust cover is fixed to the clamping groove at the top of the ball pin sleeve through a lower clamping spring, and an upper clamping spring is provided on the inner side of the top end of the dust cover.

7. The double-seal structure ball pin according to claim 5, characterized in that: A cone ring is also provided on the peripheral side of the ball pin rod at the top of the dust cover.

8. The double-seal structure ball pin according to claim 3, characterized in that: A circular protrusion is provided on the bottom plate of the protective sleeve, and the circular protrusion is adapted to the shape of the opening at the bottom of the ball pin. The protective sleeve presses the rubber end cover tightly through the circular protrusion.

9. A suspension system, characterized in that: The suspension system includes a double-sealed ball pin as described in any one of claims 1-8, wherein the top end of the ball pin rod on the double-sealed ball pin is used to connect to the steering knuckle, and the ball pin sleeve is provided with a connecting end for connecting to the front swing arm.

10. An automobile, characterized in that: A vehicle is provided with the suspension system as claimed in claim 9.

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