A kind of intermediate shaft dust cover for automobile steering system
Patent Information
- Application Number
- CN202522409801.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-13
- Publication Date
- 2026-10-23
- Estimated Expiration
- 2035-11-13
AI Technical Summary
针对传统防尘罩“装配复杂、密封差、隔音弱”的问题，本结构通过“一体化注塑+台阶式隔音装配”实现突破，上防尘罩骨架与环形隔板为基础支撑，热塑性弹性体包胶注塑成型，使骨架与包胶紧密结合，避免部件松脱，下防尘罩密封帽卡接于骨架开口，与环形隔板形成安装台阶，为吸音棉提供稳定安装空间，吸音棉外圈与密封帽紧配、下端压盖隔板，确保长期振动下不移位，有效吸收发动机舱噪声，橡胶密封帽与弹性体包胶形成材料互补密封，提升防尘隔水性能，适配汽车转向系统“动态密封+降噪”的双重需求，解决中低档轿车驾驶舱噪声大、密封性差的痛点
（一）通过上防尘罩骨架、环形隔板与上防尘罩包胶的注塑成型，以及下防尘罩骨架通过卡扣、卡接孔与卡槽的配合，实现了多部件之间的快速、稳固连接，结构紧凑，拉脱力高，有效防止松脱和异响；
Smart Images
Figure CN224886325U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of dust cover technology, specifically a dust cover for the intermediate shaft of an automobile steering system. Background Technology
[0002] The center shaft dust cover of a car steering column is a critical sealing component installed between the engine compartment and the passenger compartment. Its performance directly affects the vehicle's NVH (noise, vibration, and harshness) performance and sealing. For mid-to-low-end family cars, loud cabin noise and poor sealing are common problems that seriously affect driving and riding comfort.
[0003] Existing intermediate shaft dust covers often have shortcomings in structural design and functional integration: First, the connection structure between the various components (such as the upper cover, lower cover, and frame) is complex, making assembly inconvenient and inefficient, and prone to producing abnormal noises or loosening under long-term vibration. Secondly, the simple sealing structure makes it difficult to form an effective dynamic seal at the joints of multiple components, resulting in unsatisfactory water and dust prevention effects; Furthermore, insufficient consideration is given to the specific design for sound insulation and noise reduction, or the sound insulation materials are not installed securely, making them prone to displacement or failure, which greatly reduces the sound insulation effect.
[0004] Therefore, there is an urgent need for a compact, reliable, well-sealed, and sound-insulating intermediate shaft dust cover. Utility Model Content
[0005] The purpose of this utility model is to overcome the shortcomings of the prior art and provide an intermediate shaft dust cover, which has the characteristics of compact structure, convenient assembly, reliable connection, good sealing and good sound insulation.
[0006] This utility model proposes a dust cover for the intermediate shaft of an automotive steering system, comprising: an upper dust cover frame, which is annular and has circumferentially distributed annular partitions inside; an upper dust cover rubber coating, which is made of thermoplastic elastomer material wrapping the lower edge of the upper dust cover frame and the annular partitions and injection molded therein; a lower dust cover sealing cap, which is injection molded from rubber material and snapped into the upper opening of the upper dust cover frame, and presses against the upper surface of the annular partitions; the lower part of the lower dust cover sealing cap contacts the outer ring of the annular partitions to form an installation step; and an annular sound-absorbing cotton, which is disposed on the installation step; the outer ring of the sound-absorbing cotton is tightly fitted with the lower inner ring of the lower dust cover sealing cap, and its lower end face presses against the upper surface of the annular partitions; Addressing the issues of complex assembly, poor sealing, and weak sound insulation in traditional dust covers, this structure achieves a breakthrough through "integrated injection molding + stepped sound insulation assembly." The upper dust cover frame and annular partition serve as the basic support, with thermoplastic elastomer overmolded and injection molded to ensure a tight bond between the frame and the overmolded material, preventing components from loosening. The lower dust cover sealing cap snaps into the frame opening, forming an installation step with the annular partition, providing a stable installation space for the sound-absorbing cotton. The outer ring of the sound-absorbing cotton fits tightly with the sealing cap, and the lower end presses against the partition, ensuring it does not shift under long-term vibration and effectively absorbing engine compartment noise. The rubber sealing cap and the elastomer overmolded material form a complementary seal, improving dust and water resistance performance. It meets the dual requirements of "dynamic sealing + noise reduction" in automotive steering systems, solving the pain points of high cabin noise and poor sealing in mid-to-low-end cars.
[0007] As a further optimization of this utility model, an annular protrusion is provided on the lower outer periphery of the sound-absorbing cotton, and the annular protrusion is locked with the inner wall of the lower dust cover sealing cap. The lower end of the sound-absorbing cotton has an annular protrusion that clamps tightly to the inner wall of the sealing cap, forming a "double fixation"—both through step-limiting and protrusion-clamping, preventing the sound-absorbing cotton from shifting due to vehicle vibration. This reduces the shift rate and ensures long-lasting sound insulation. Moreover, the protrusion design does not affect the porous sound insulation structure of the sound-absorbing cotton, while enhancing the fit with the sealing cap, reducing noise penetration through gaps, and further improving sound insulation performance. This makes it suitable for automotive operating conditions with long-term high-frequency vibrations, such as bumpy roads and engine vibrations.
[0008] As a further optimization of this utility model, the lower end of the sealing cap of the lower dust cover is provided with an outwardly turned sealing lip, and the sealing lip is interference-fitted with the upper inner wall of the upper dust cover frame and locked in place. The outward-facing sealing lip is press-fitted with the inner wall of the skeleton to form a physical sealing barrier, preventing water and dust from entering through the gap between the skeleton and the sealing cap. This improves the dustproof and water-proof rates. The lip has strong elastic deformation capability, which can adapt to the dynamic movement of the steering system, such as the rotation of the intermediate shaft and the displacement of bumps, and always maintain a tight fit. This avoids the sealing failure caused by movement of traditional rigid seals. This structure does not require additional sealing components, simplifies assembly, and improves the reliability of dynamic sealing, making it suitable for the complex motion conditions of automotive steering systems.
[0009] As a further optimization of this utility model, it also includes a lower dust cover frame; the lower end of the lower dust cover frame is adapted to the shape of the sealing lip and inserted therein; a plurality of circumferentially distributed buckles are provided on the outer periphery of the lower end of the lower dust cover frame; a plurality of snap-fit holes corresponding one-to-one with the buckles are provided on the sealing lip; the buckles radially penetrate the snap-fit holes and snap-fit with the slots opened on the inner wall of the upper dust cover frame. The lower dust cover frame achieves a stable connection of multiple components through "lip fitting + snap-fit": the lower end of the frame is inserted into the sealing lip to ensure accurate positioning, and the snap-fit passes through the snap-fit hole of the sealing lip and is locked with the frame slot, locking the lower frame, sealing cap and upper frame together. It has strong pull-out force and is resistant to loosening, avoiding abnormal noise or separation caused by long-term vibration. This connection structure is easy to assemble (insert and lock), requires no tools, improves production efficiency, and the circumferential distribution of multiple snap-fits ensures uniform force distribution, adapting to the vibration environment of automotive steering systems.
[0010] As a further optimization of this utility model, a handle is installed at the upper end of the lower dust cover frame, and a space for hand operation is reserved between the handle and the outer surface of the lower dust cover sealing cap. The handle provides a force point for assembly, conforms to ergonomics, and allows operators to easily grip the handle to complete the overall installation or removal of the dust cover, shortening assembly time. The reserved operating space avoids interference between the hand and the sealing cap, ensuring convenient assembly. The handle is made of lightweight material, which does not increase the overall weight of the dust cover, while the structure is stable and there is no risk of breakage. It is suitable for the high-efficiency assembly needs of automotive production lines and reduces the intensity of manual operation.
[0011] As a further optimization of this utility model, the upper dust cover with rubber coating and the upper end of the lower dust cover sealing cap are both press-fitted with bearing assemblies, and the two bearing assemblies are coaxially aligned. The bearing assembly is press-fitted onto the top of the rubber-coated and sealing cap, and coaxial alignment ensures smooth rotation of the intermediate shaft. The bearing provides radial support for the intermediate shaft, reducing wear on the dust cover caused by shaft wobble and extending the dust cover's lifespan. At the same time, the integrated design of the bearing assembly and dust cover avoids the cumbersome installation of the bearing separately, improves the overall structural compactness, and is suitable for the limited installation space of automotive steering systems, ensuring precise and stable steering operation.
[0012] As a further optimization of this utility model, the bearing assembly includes an inner bearing ring, a bearing cage, and an outer bearing ring, and the gap between the inner bearing ring and the bearing cage is filled with grease. The inner ring of the bearing rotates synchronously with the intermediate shaft, the cage guides the movement of the rolling elements, and the outer ring is fixed to the dust cover to ensure smooth rotation. The grease in the gap forms an oil seal to prevent impurities from entering the bearing and reduce bearing noise. It meets the NVH performance requirements of automobiles. The grease is stable for a long time and does not need to be replenished frequently, making it suitable for long-term use in automobiles and reducing maintenance costs.
[0013] As a further optimization of this utility model, the thermoplastic elastomer material is TPV, which combines the elasticity of rubber and the processability of plastic. After injection molding, it is tightly bonded to the upper dust cover frame, with no risk of delamination. It also has excellent weather resistance, resists high and low temperatures and aging, and is suitable for temperature fluctuations in the car engine compartment. Moreover, TPV has good elasticity and can adapt to the dynamic deformation of the steering system, ensuring a long-lasting seal. Compared with traditional rubber materials, it has a longer service life and a longer maintenance cycle.
[0014] As a further optimization of this utility model, the rubber material is EPDM, which has excellent ozone resistance and aging resistance. It is not easily deteriorated when exposed to the harsh environment of the engine compartment for a long time. Moreover, it has good elasticity and can maintain its deformation for a long time after the sealing lip is interference fit, ensuring the sealing effect. At the same time, EPDM has better sound insulation performance than ordinary rubber, which can help the sound-absorbing cotton to further reduce noise transmission. It meets the multiple performance requirements of "sealing + sound insulation + weather resistance" of car dust covers, and improves product reliability and life.
[0015] The dust cover for the intermediate shaft of an automotive steering system proposed in this utility model has the following beneficial effects: (i) Through the injection molding of the upper dust cover frame, the annular partition and the upper dust cover rubber coating, and the lower dust cover frame through the cooperation of buckles, snap holes and slots, a fast and stable connection between multiple parts is achieved. The structure is compact, the pull-out force is high, and it effectively prevents loosening and abnormal noise. (ii) The lower dust cover sealing cap made of EPDM material and the upper dust cover made of TPV material are coated to form a material complementary seal. The sealing lip and the inner wall of the upper dust cover skeleton form a physical seal. The grease in the bearing assembly forms an oil seal. Together, they form an effective multi-dynamic sealing system with excellent water and dust resistance. (iii) A stepped structure was specially designed for installing the ring-shaped sound-absorbing cotton, and the ring protrusion is locked with the sealing cap of the lower dust cover, so that the sound-absorbing cotton is firmly installed and not easy to move, and can continuously and effectively absorb and block the noise transmitted from the engine compartment to the cockpit. (iv) The plastic handle integrated on the lower dust cover frame provides great convenience for assembly and conforms to ergonomics. At the same time, the matching structure of the buckle and the snap hole makes the assembly process of the upper and lower parts simple and quick, improving production efficiency.
[0016] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description
[0017] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a bottom view of the structure of this utility model; Figure 3 This is a schematic diagram of the exploded structure of this utility model; Figure 4 This is a schematic diagram of the structure of the lower dust cover frame of this utility model; Figure 5 This is a three-dimensional cross-sectional structural diagram of the present invention; Figure 6 This is a front sectional view of the present invention. Figure 7 This utility model Figure 6 Enlarged structural diagram at point A; Figure 8 This is a cross-sectional structural diagram of the bearing assembly of this utility model.
[0018] Attached diagram descriptions: 1. Upper dust cover frame; 2. Upper dust cover rubber coating; 3. Lower dust cover frame; 31. Buckle; 4. Lower dust cover sealing cap; 41. Sealing lip; 42. Snap-fit hole; 5. Sound-absorbing cotton; 6. Bearing assembly; 61. Bearing inner ring; 62. Bearing cage; 63. Bearing outer ring; 64. Lubricating grease; 7. Handle. Detailed Implementation
[0019] The embodiments of this utility model are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar symbols denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.
[0020] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.
[0021] Please see Figures 1-8The dust cover for the intermediate shaft of an automotive steering system provided by this utility model includes an upper dust cover frame 1, an upper dust cover rubber coating 2, a lower dust cover frame 3, a lower dust cover sealing cap 4, and sound-absorbing cotton 5. The upper dust cover frame 1 is annular and has circumferentially distributed annular partitions inside. The upper dust cover rubber coating 2 is formed by injection molding TPV material around the lower edge of the upper dust cover frame 1 and the annular partitions into the upper dust cover frame 1. The lower dust cover sealing cap 4 is made of EPDM material. The lower dust cover sealing cap 4 is injection molded and snapped into the upper opening of the upper dust cover frame 1 and presses over the upper surface of the annular partition. The lower part of the lower dust cover sealing cap 4 contacts the outer ring of the annular partition to form a step for installing the sound-absorbing cotton 5. The sound-absorbing cotton 5 is annular. The outer ring of the sound-absorbing cotton 5 is adapted to and tightly attached to the lower inner ring of the lower dust cover sealing cap 4. The lower end face of the sound-absorbing cotton 5 presses over the upper surface of the annular partition, and the lower outer periphery of the sound-absorbing cotton 5 has an annular protrusion that is snapped into the lower dust cover sealing cap 4. like Figure 3 , Figure 5 , Figure 6 , Figure 7 As shown, the lower dust cover sealing cap 4 has an outwardly turned sealing lip 41 at its lower end. The sealing lip 41 is clamped to the upper inner wall of the upper dust cover frame 1. The lower end of the lower dust cover frame 3 is adapted to the sealing lip 41 and inserted into the sealing lip 41. The lower outer periphery of the lower dust cover frame 3 has multiple circumferentially distributed buckles 31. The buckles 31 radially penetrate the snap-fit hole 42 and snap-fit with the 11 opened on the inner wall of the upper dust cover frame 1, thereby realizing the quick and stable assembly of the upper dust cover frame 1, the lower dust cover frame 3, and the lower dust cover sealing cap 4. like Figures 3-7 As shown, the sealing lip 41 has a plurality of circumferentially distributed snap-fit holes 42, and the plurality of snap-fit holes 42 correspond one-to-one with the plurality of snap fasteners 31. During assembly, the snap fasteners 31 pass through the snap-fit holes 42 and extend to the outside of the sealing lip 41, and snap with 11. like Figure 1 , Figure 3 and Figure 4 As shown, a handle 7 is also installed at the upper end of the lower dust cover frame 3. The handle 7 is a plastic handle and has enough hand space with the outer surface of the lower dust cover sealing cap 4, which facilitates actual assembly operation and conforms to ergonomics. like Figure 1 , Figure 5 and Figure 6 As shown, the upper ends of the upper dust cover rubber coating 2 and the lower dust cover sealing cap 4 are both press-fitted with bearing assemblies 6 to ensure that they are not easy to fall off, and the two bearing assemblies 6 are coaxially aligned. like Figure 8As shown, the bearing assembly 6 includes an inner bearing ring 61, a bearing cage 62 for engaging the inner bearing ring 61, and an outer bearing ring 63. The inner bearing ring 61 is interference-fitted with the intermediate shaft and rotates synchronously with the shaft. The gap between the inner bearing ring 61 and the bearing cage 62 is filled with grease 64.
[0022] The working principle of this utility model revolves around its three core functions: "compact connection," "multiple sealing," and "high-efficiency sound insulation," as detailed below: The upper dust cover frame 1 and its internal annular partition are encapsulated with TPV material to form the upper dust cover coating 2, which constitutes a structurally stable integrated basic component. The lower dust cover frame 3 achieves a quick connection of "insertion-rotation-clamping" or "direct pressure" through the cooperation of the buckle 31 at its lower end, the snap hole 42 on the lower dust cover sealing cap 4, and the slot 11 on the inner wall of the upper dust cover frame 1. This structure tightly locks the lower dust cover frame 3, the lower dust cover sealing cap 4, and the upper dust cover frame 1 together, ensuring a reliable connection. During installation, the operator can hold the handle 7 on the lower dust cover frame 3 to easily align the entire component with the installation position, and then apply pulling force to make the buckle mechanism take place. The assembly process is labor-saving and efficient. The sealing lip 41 of the lower dust cover sealing cap 4 is press-fitted with the upper inner wall of the upper dust cover frame 1 to form a tight physical seal and block external water and dust. The TPV material of the upper dust cover coating 2 and the EPDM material of the lower dust cover sealing cap 4 both have good elasticity and sealing performance, adapt to different working temperatures and environments, and together form a sealing barrier at the material level. The grease 64 injected into the bearing assembly 6 forms an effective oil seal in the gap between the bearing inner ring 61 and the cage 62, preventing contaminants from entering axially along the intermediate shaft, while ensuring the smooth operation of the bearing itself. The sound-absorbing cotton 5 is precisely confined within the stepped space formed by the lower dust cover sealing cap 4 and the annular partition, and is secured to the lower dust cover sealing cap 4 by its own annular protrusion, preventing loosening or displacement under vehicle vibration and ensuring the durability of the sound insulation effect. When noise waves from the engine compartment attempt to enter the cabin through the dust cover, they encounter this firmly fixed layer of sound-absorbing cotton 5. The porous structure of the sound-absorbing cotton causes the sound waves to be repeatedly refracted and rubbed within it, effectively converting sound energy into heat energy and consuming it, thereby significantly attenuating the transmission intensity of noise and improving the quietness inside the vehicle.
[0023] In summary, this utility model achieves convenient and reliable assembly through a unique snap-fit connection structure, forms multiple dynamic sealing defenses through a sealing lip, special materials and lubricant, and ensures excellent and long-lasting sound insulation effect through a dedicated fixing structure designed for the sound-absorbing cotton. Its overall performance is significantly better than that of traditional dust covers.
[0024] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.
Claims
1. A dust cover for the intermediate shaft of an automotive steering system, characterized in that, include: The upper dust cover frame (1) is ring-shaped and has circumferentially distributed ring-shaped partitions inside; The upper dust cover is coated with rubber (2), which is made of thermoplastic elastomer material that wraps the upper dust cover frame (1) and the lower edge of the annular partition and is injection molded into it; The lower dust cover sealing cap (4) is injection molded from rubber material and snapped into the upper opening of the upper dust cover frame (1), and presses against the upper surface of the annular partition. The lower part of the lower dust cover sealing cap (4) contacts the outer ring of the annular partition to form an installation step; An annular sound-absorbing cotton (5) is disposed on the mounting step; The outer ring of the sound-absorbing cotton (5) is tightly fitted with the lower inner ring of the lower dust cover sealing cap (4), and its lower end face presses against the upper surface of the annular partition.
2. A dust cover for an intermediate shaft in an automotive steering system according to claim 1, characterized in that, The lower outer periphery of the sound-absorbing cotton (5) is provided with an annular protrusion, which is locked with the inner wall of the lower dust cover sealing cap (4).
3. A dust cover for an intermediate shaft in an automotive steering system according to claim 1, characterized in that, The lower end of the lower dust cover sealing cap (4) is provided with an outwardly turned sealing lip (41), and the sealing lip (41) is interference-fitted with the upper inner wall of the upper dust cover frame (1) and locked in place.
4. A dust cover for an intermediate shaft in an automotive steering system according to claim 3, characterized in that, It also includes the lower dust cover frame (3); The lower end of the lower dust cover frame (3) is adapted to the shape of the sealing lip (41) and inserted therein; The lower dust cover frame (3) is provided with multiple buckles (31) evenly distributed in the circumference at its lower outer periphery. The sealing lip (41) has a plurality of snap-fit holes (42) that correspond one-to-one with the buckle (31). The buckle (31) penetrates radially through the snap-fit hole (42) and snaps into the slot (11) opened on the inner wall of the upper dust cover frame (1).
5. A dust cover for an intermediate shaft in an automotive steering system according to claim 4, characterized in that, A handle (7) is installed at the upper end of the lower dust cover frame (3), and a space for hand operation is reserved between the handle (7) and the outer surface of the lower dust cover sealing cap (4).
6. A dust cover for an intermediate shaft in an automotive steering system according to claim 1, characterized in that, The upper ends of the upper dust cover rubber coating (2) and the lower dust cover sealing cap (4) are both press-fitted with bearing assemblies (6), and the two bearing assemblies (6) are coaxially aligned.
7. A dust cover for an intermediate shaft in an automotive steering system according to claim 6, characterized in that, The bearing assembly (6) includes an inner bearing ring (61), a bearing cage (62) and an outer bearing ring (63), and grease (64) is injected into the gap between the inner bearing ring (61) and the bearing cage (62).
8. A dust cover for an intermediate shaft in an automotive steering system according to claim 1, characterized in that, The thermoplastic elastomer material is TPV.
9. A dust cover for an intermediate shaft in an automotive steering system according to claim 1, characterized in that, The rubber material is EPDM.