A water-blocking sealing strip, car door and automobile

Abstract

This application discloses a water-retaining sealing strip, a car door, and an automobile, aiming to solve the problems of insufficient sealing performance and easy dynamic noise generation of existing sealing strips under extreme working conditions. The water-retaining sealing strip includes a fixed mounting structure, a hollow compression sealing structure, and a supporting lip. The supporting lip is disposed on the fixed mounting structure and extends into the hollow area of ​​the compression sealing structure. When the compression sealing structure is deformed under pressure to a preset assembly position (D0), the top of the supporting lip abuts against the inner wall of the compression sealing structure. This application significantly improves the sealing reliability and durability of the sealing strip in deep wading environments and under extreme working conditions such as surging waves without worsening the conventional door closing force, and effectively suppresses dynamic noise.

Description

Technical Field

[0001] This application relates to the field of automotive parts technology, specifically to a water-blocking automotive sealing strip. Background Technology

[0002] Current national standards do not specify unified wading depth requirements for gasoline-powered vehicles. However, the wading performance testing requirements for electric vehicles are mainly reflected in the "Safety Requirements for Electric Vehicles" (GB18384-2020). Specifically, in the "Simulated Wading" section of the "Vehicle Waterproofing" standard, it stipulates that the vehicle must travel at a speed of (20±2) km / h for at least 500 meters in a 100mm deep pool. This standard only represents the minimum safety requirements for electric vehicles and can only prove the vehicle's waterproofing capability under specific conditions for a short period. It does not represent the product's ability to cope with extreme weather or complex wading scenarios. For example, in urban flooding caused by heavy rain, the water depth often far exceeds 100mm, or in rivers and shallows encountered by vehicles during off-road driving, the water depth and flow conditions are even more complex. In the high-end vehicle segment, especially for rugged off-road vehicles and luxury all-terrain SUVs, the design must not only meet the comfort requirements of urban driving but also cope with complex water-crossing scenarios—from flooded roads after heavy rain to traversing shallow waters, and even emergency water crossing needs in extreme environments, where water depths can easily exceed 1000mm and the impact of surging waves must be faced. Users of these types of vehicles have extremely high requirements for vehicle passability and reliability, and the sealing strips, as the core barrier preventing water from entering the cabin, directly determine the safety and durability of the vehicle under water-crossing conditions.

[0003] To address this, some OEMs have set water depths of up to 1200mm in their specialized wading tests for their high-end models, far exceeding the 300-500mm safety threshold for ordinary vehicles. They have also introduced dynamic wading scenario simulations, requiring vehicles to enter deep water at a speed of 8.5 knots (approximately 15.7 km / h) and withstand surge water pressure of around 25,000 Pa. This, combined with the impact of water flow and wave disturbance during deep wading, creates a continuous high-intensity load on the sealing strips. The vehicle must complete round-trip driving and stop-and-go maneuvers at a depth of 1200mm. After the test, it must be ensured that there is no water leakage in the cabin and that the insulation resistance of the electrical system meets the standard (referring to the enhanced standard GB18384-2020). This presents an unprecedented challenge to the sealing reliability of the sealing strips.

[0004] Traditional door frame sealing strips exhibit significant shortcomings when facing such extreme conditions. Traditional sealing strips typically employ a single sealing lip structure, whose contact pressure with the door frame sheet metal is insufficient to withstand the surge impact at a water depth of 1200mm. When a vehicle is traveling at 15.7km / h, the impact force of the water flow on the sealing strip can reach 1.5 times the static water pressure, causing the sealing lip to separate from the sheet metal and create a gap. Under the impact of water pressure, a "bulging" phenomenon occurs, allowing water to seep into the cabin along the gap, thereby affecting the normal operation of in-vehicle electrical equipment (such as seat adjustment motors and ambient lighting modules).

[0005] While adding a foam layer can improve static sealing in existing solutions, it increases the weight of the sealing strip (high-end vehicles have stringent lightweight requirements), and it is prone to deformation due to insufficient rigidity under dynamic water pressure. Using a metal skeleton reinforcement structure sacrifices the sealing strip's low-temperature elasticity, potentially leading to seal failure in cold regions due to increased brittleness. Therefore, traditional door frame sealing strips are insufficient to meet the performance requirements of high-end vehicles with their demanding water-wading needs, necessitating the development of new water-resistant sealing strips adapted to severe water-wading conditions. Utility Model Content

[0006] A water-blocking sealing strip, comprising: A fixed installation structure is used to install the water-blocking sealing strip onto the vehicle body sheet metal, the fixed installation structure including a first fixed connection part; A hollow compression sealing structure is integrally connected with the fixed installation structure and is used to seal the gap when under pressure. A supporting lip is provided, which is connected to the first fixed connection part of the fixed installation structure via a supporting lip connecting part and extends into the hollow area of ​​the compression sealing structure. The support lip has a support lip protrusion protruding toward the inner wall of the compression sealing structure, and a support lip top located at its end; and when the compression sealing structure is deformed under pressure to a preset assembly position (D0), the support lip top abuts against the inner wall of the compression sealing structure to provide internal support for the compression sealing structure.

[0007] Furthermore, the supporting lip also includes a supporting lip recess; and, on the inner wall of the compression sealing structure, there are first bubble tube protrusions and second bubble tube protrusions opposite to the supporting lip recess, and first bubble tube recesses and second bubble tube recesses respectively corresponding to the bubble tube protrusions; the structure allows the first bubble tube protrusions and second bubble tube protrusions to undergo complementary contraction deformation towards their corresponding first bubble tube recesses and second bubble tube recesses respectively when the compression sealing structure is compressed, in order to disperse local extrusion stress and avoid sealing failure due to excessive deformation.

[0008] Furthermore, the first fixed connection portion is provided with a fixed inner recess, the position of which is opposite to the first bubble tube protrusion and / or the second bubble tube protrusion, so as to guide and accommodate the deformation of the bubble tube protrusion when the compression sealing structure is compressed, thereby maintaining its effective fit and sealing pressure with the support lip recess.

[0009] Furthermore, the fixed mounting structure also includes a fixed lip extending therefrom; the fixed lip is configured to pre-deform after installation, thereby generating a continuous rebound force to fit tightly against the mounting surface; the rebound force is used to resist and balance the lateral thrust generated when the compression sealing structure is compressed, so as to ensure that the water-blocking sealing strip maintains a precise assembly posture.

[0010] Furthermore, the water-blocking sealing strip has non-linear compression characteristics, wherein: During the first compression stage from the undercompressed state to the preset assembly position, the compression load is mainly generated by the elastic deformation of the compression sealing structure; at this time, the support lip begins to come into contact with the compression sealing structure.

[0011] In the second compression stage, after entering the overcompression state from the preset assembly position (D0), the support lip begins to abut against the inner wall of the compression sealing structure and shares the pressure with the compression sealing structure. The effective stiffness K2 of the second compression stage is at least 2.5 times the effective stiffness K1 of the first compression stage.

[0012] Furthermore, at the preset assembly position (D0), the compressive load of the water-blocking sealing strip is 5 N / 100mm to 9 N / 100mm, so as to provide a sealing force that meets the waterproof performance requirements while avoiding excessive closing resistance.

[0013] Furthermore, when the water-blocking sealing strip is compressed by 1mm from the preset assembly position (D0) to the over-compression position (D0+1mm), the resulting increase in compression load is not less than 4.0 N / 100mm, so as to ensure that the sealing system can provide a strong reaction force to maintain the seal integrity when the door is dynamically offset or encounters external impact.

[0014] Furthermore, the compression sealing structure is made of EPDM sponge material with a density of 0.65±0.05g / cm³; while the fixed installation structure and the supporting lip integrally connected thereto are made of EPDM solid adhesive or micro-foamed adhesive material with a density of not less than 0.80g / cm³; the density difference of the materials constitutes the physical basis for realizing the nonlinear compression characteristics.

[0015] A type of car door is provided with the water-blocking sealing strip described above.

[0016] A type of automobile is equipped with the aforementioned water-retaining sealing strip.

[0017] This application incorporates a supporting lip structure, precisely designing the timing of its engagement with the compression sealing structure. When the door is closed normally, the sealing strip relies on the initial contact between the compression sealing structure and the lip to provide sealing force, meeting the requirements for low closing resistance and basic sealing performance. When entering over-compression states such as deep wading, the supporting lip begins to bear force rapidly, significantly increasing the effective stiffness of the sealing system, and the surge in compressive load forms a rigid support structure. CAE analysis and experimental verification show that the sealing strip of this application has an ultimate water pressure resistance of 145,800 Pa, more than 20 times higher than traditional sealing strips, solving the technical problem of traditional sealing strips' inability to simultaneously handle normal closing force and sealing performance under extreme conditions.

[0018] Traditional sealing designs, under over-compression conditions, are prone to causing rigid impacts between the door and the body sheet metal, resulting in knocking, friction, and other abnormal noises. The support lip in this application acts as a pre-set elastic buffer element during the over-compression stage, transforming the rigid impact into a controllable process of elastic potential energy absorption and dissipation. By providing progressive support force, it continuously buffers and isolates the relative displacement between the door and the body, effectively suppressing abnormal noises caused by dynamic impacts and improving the vehicle's NVH performance.

[0019] This application is not a simple structural superposition, but rather a deep collaborative design of each component: the "bulb tube protrusion / recess" of the compression sealing structure and the "support lip recess" of the support lip form complementary contractions to achieve stress dispersion; the "fixed inner recess" of the fixed installation structure provides a preset space for the deformation of the bulb tube protrusion, avoiding irreversible damage; the pre-tightening force generated by the "fixed lip" can resist the lateral thrust during compression. This collaborative design ensures that the sealing strip can maintain a precise assembly posture and durable and stable sealing performance even under long-term, repeated, and complex working conditions.

[0020] In summary, this application, through structural innovation, enables the sealing strip to adaptively enhance its resistance under extreme working conditions without increasing assembly difficulty or significantly increasing conventional closing force. This achieves a comprehensive improvement in sealing performance, NVH performance, durability, and user experience, ensuring the robustness of the sealing system. Attached Figure Description

[0021] Figure 1 This is an overall structural diagram of the sealing strip in this application.

[0022] Figure 2 This is a cross-sectional view showing the sealing strip of this application being fixed with a snap fastener.

[0023] Figure 3 This is a cross-sectional view showing the sealing strip of this application fixed with tape.

[0024] Figure 4 This is a cross-sectional view of the sealing strip in this application.

[0025] Figure 5 For comparison, see the cross-sectional view of the sealing strip.

[0026] Figure 6 This is a schematic diagram showing the positions of four cross-sections (AA, BB, CC, DD) and the sheet metal.

[0027] Figure 7 The assembly test process of adding a support lip to the traditional sealing strip and then attaching it to the sheet metal is shown in the diagram.

[0028] Figure 8 This is a diagram illustrating another comparative water immersion test process for sealing strips.

[0029] Figure 9 This is a diagram illustrating the water immersion test process of the sealing strip in this application.

[0030] Figure 10 This application contains a diagram illustrating the assembly and testing process of the sealing strip.

[0031] 100. Adhesive strip body; 101. Buckle; 102. Adhesive tape; 103. Butt joint; 300. Section; 310. Compression sealing structure (bubble tube); 311. First bubble tube end; 312. Second bubble tube end; 313. Bubble tube support; 314. First bubble tube protrusion; 315. First bubble tube recess; 316. Second bubble tube protrusion; 317. Second bubble tube recess; 320. Support lip; 321. Support lip protrusion; 322. Support lip recess; 323. Support lip top; 324. Support lip connecting part; 330. Through hole; 340. Fixed installation structure; 341. First fixed end; 342. Second fixed end; 343. Fixed inner recess; 344. Fixed support part; 345. Fixed lip; 346. Fixed outer recess; 347. First fixed connecting part; 348. Second fixed connecting part; 400. Comparison strip cross-section. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the described embodiments of this application are within the scope of protection of this application.

[0033] To better describe and illustrate the embodiments of this application, reference may be made to one or more accompanying drawings, but the additional details or examples used to describe the drawings should not be considered as limiting the scope of any of the inventive creations of this application, the embodiments or preferred methods described herein.

[0034] In the description of this invention, it should be noted that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the positional relationship shown in the corresponding drawings. They are only for the convenience of describing this invention and do not indicate that the device referred to must have a specific orientation or operate in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0036] The compressive load of a sealing strip refers to the force it withstands when compressed, usually expressed as the force per unit length (e.g., per 100mm). It is an important indicator of the sealing strip's performance. Insufficient compressive load will prevent the sealing strip from adhering tightly to the sealing surface, easily leading to gaps and resulting in water leakage, air leakage, and poor sound insulation. Excessive compressive load may over-compress the sealing surface (such as in car doors and window frames), causing deformation or wear of the contact surface, thus compromising the seal. Based on numerous experiments conducted by the inventors, we found that controlling the compressive load to 7±2N / 100mm is necessary to meet waterproof performance requirements.

[0037] Test standards and requirements: The compression load test shall be conducted in accordance with QC / T 710-2004 "Test method for compression load of automotive sealing strips".

[0038] Water Wading Test: The vehicle should have the ability to propel itself by floating in water. Test conditions refer to the "Simulated Wading" section of GB 18384-2020 "Safety Requirements for Electric Vehicles," specifically the "Vehicle Waterproofing" part. In a 1200mm deep pool, a wave machine simulates a 25000Pa surge water pressure environment. After entering the pool, the vehicle transitions to a floating state and engages the floating propulsion mode until it reaches a speed of 8.5 knots (including straight driving and U-turns). The total test time should be no less than 30 minutes. After the test, observe the interior of the doors and passenger compartment for any signs of water immersion or leakage, and verify that all vehicle functions are normal.

[0039] CAE water immersion analysis: The bubble tube is made of EPDM sponge material (0.65±0.05g / cm). 3 The fixed installation structure is EPDM solid adhesive or micro-foamed adhesive (density ≥ 0.80 g / cm³). 3 The material has a hardness of 70 (Shore A). The material model was established based on the mechanical experimental fitting of the rubber specimen, and the coefficient of friction was 0.30.

[0040] Door sealing strips are mainly used for fixing, dust removal, and sealing of car doors. They are primarily made of ethylene propylene diene monomer (EPDM) rubber, and are composed of a composite of foam and solid rubber, or entirely of foam.

[0041] A car door sealing strip typically consists of a compression sealing structure 310 and a fixed installation structure 340. The compression sealing structure 310 serves as the core component of the door sealing strip, commonly known as a foam tube. It is usually made of EPDM foam rubber and requires the addition of vent holes with a certain spacing and number during vulcanization to facilitate compression and venting. When the door is closed, the foam tube is compressed and tightly fitted by matching parts such as the side panel to form a sealing structure, thereby isolating the inside and outside of the car compartment.

[0042] The fixed mounting structure 340 is used to help the sealing strip firmly bond to the door sheet metal and prevent the sealing strip from falling off. Currently, the materials for the fixed mounting structure 340 are EPDM foam rubber and EPDM solid rubber. There are three fixing methods for connecting the sealing strip to the door sheet metal: fixing with clips 101, fixing with tape 102, and fixing with sheet metal roll-formed guide rail grooves. Usually, one of the three fixing methods is selected or used in combination.

[0043] D0 is short for Design Zero, which represents the ideal alignment between the door and the outer side panel when the door is closed. Generally, the alignment between the door seal and the outer side panel needs to meet a tolerance range of D0 ± 2 mm to ensure sealing performance and appearance quality.

[0044] Figure 1 This is a schematic diagram of the overall structure of the water-blocking sealing strip of this application. As a preferred design, we chose to fix the sealing strip above the window frame (ROOF section) to the sheet metal using plastic clips 101, while fixing the other parts using tape 102. Those skilled in the art can choose to fix the sealing strip entirely with plastic clips 101 or entirely with tape 102 when implementing this technical solution. Those skilled in the art can flexibly adjust the fixing method according to the specific needs of the actual application scenario, and are not limited to the above preferred solution.

[0045] Figure 2 and Figure 3 These are specific schematic diagrams of two fixed forms. Figure 2This is a cross-sectional view 300 showing the sealing strip of this application being fixed by a snap fastener 101. One end of the snap fastener 101 is located within the fixed installation structure 340. Specifically, one end of the snap fastener 101 passes through the second fixed connection part 348 and is positioned within the through hole 330, while the other end is a pointed tip. During vehicle installation, the snap fastener 101 can be engaged with the holes in the vehicle door sheet metal. Through the mechanical interlocking structure between the snap fastener 101 and the sheet metal holes, reliable fixing of the sealing strip to the vehicle door sheet metal is achieved, ensuring the connection stability of the sealing structure under conditions such as vehicle vibration and wind pressure. Figure 3 This is a cross-sectional view 300 showing the sealing strip of this application being fixed with adhesive tape 102. Adhesive tape 102 is disposed on one side of the fixing and mounting structure 340. Specifically, one side of adhesive tape 102 is bonded to the second fixing connection part 348, and the protective layer on the other side of adhesive tape 102 is not removed initially. During vehicle installation, the protective layer of adhesive tape 102 is removed, and the sealing strip is bonded to the door sheet metal. The adhesive medium of adhesive tape 102 is used to bond and fix the sealing strip to the surface of the door sheet metal, completing the sealing connection between the sealing strip and the sheet metal.

[0046] Figure 4 This is a 300° cross-sectional view of the sealing strip in this application. Figure 5 To compare the cross-sectional view 300 of the sealing strip, the distinguishing feature between the two is the presence or absence of a supporting lip 320.

[0047] Specifically Figure 4The water-blocking sealing strip of this application consists of a compression sealing structure (foam tube) 310 and a fixed installation structure 340. From the perspective of material selection, as a preferred embodiment of this application, the compression sealing structure (foam tube) 310 is made of foamed EPDM material, and the fixed installation structure 340 is made of EPDM solid adhesive or micro-foamed material (density ≥ 0.80 g / cm3). The compression sealing structure (foam tube) 310 and the fixed installation structure 340 are co-extruded and molded, and after vulcanization and setting, the water-blocking sealing strip is obtained. The bubble tube 310 is generally arc-shaped. The first end 311 of the bubble tube is fixedly connected to the first fixed end 341 of the fixed mounting structure 340, and the second end 312 of the bubble tube is fixedly connected to the second fixed end 342 of the fixed mounting structure 340. Its spatial position allows it to cover the supporting lip 320. Simultaneously, a specific gap naturally forms between the bubble tube 310 and the fixed mounting structure 340; this gap is referred to as the inner side of the bubble tube 310, and the other side as the outer side. This gap provides deformation buffer space when the sealing strip is compressed, helping to optimize sealing performance. After the door is closed, the bubble tube deforms due to the compression of the contact surface, and its arc surface tightly fits the vehicle body sealing surface, forming a continuous elastic sealing band. This deformation can fill the assembly gaps and minor tolerances between components, and even offset gap fluctuations caused by vehicle vibration, thereby effectively blocking the intrusion of external debris such as rainwater, dust, and mud, while reducing the transmission of interior noise (such as wind noise).

[0048] Specifically, the compression sealing structure 310, in addition to the aforementioned first bubble tube end 311 and second bubble tube end 312, also includes a bubble tube support part 313. On the one hand, the bubble tube support part 313 can cooperate with the fixed support part 344 to ensure that the sealing strip is in a balanced position after installation. On the other hand, it can cover the buckle 101 or tape 102 to prevent the buckle 101 / tape 102 from being directly exposed to the external environment, making the sealing strip look more regular and improving the overall assembly aesthetics.

[0049] On the inner wall of the bubble tube 310 opposite the support lip recess 322 on the support lip 320, a first bubble tube protrusion 314, a first bubble tube recess 315, a second bubble tube protrusion 316, and a second bubble tube recess 317 are sequentially arranged, that is, the first bubble tube protrusion 314 and the second bubble tube protrusion 316 are opposite to the support lip recess 322. When the car door is closed, the bubble tube 310 is compressed and deformed. At this time, the first bubble tube protrusion 314 will shrink and deform towards the first bubble tube recess 315, and the second bubble tube protrusion 316 will shrink and deform towards the second bubble tube recess 317. This adaptive deformation of the protrusion and the corresponding recess can disperse the compressive stress through the complementary shrinkage of the structure, avoid the sealing failure caused by excessive local deformation, and at the same time ensure that the bubble tube 310 and the support lip 320 remain in abutting state, strengthening the basic sealing effect. When the left side of the bubble tube 320 is impacted by high-pressure water flow (i.e. Figure 4 Regarding the placement position, the car door will be further squeezed inward under the impact force, causing the matching position between the bubble tube 320 and the car door sheet metal to gradually squeeze from the initial state (D0mm) to D0+1mm and D0+2mm. With the dynamic change of the matching gap, the bubble tube 310 will undergo further deformation: the degree of contraction of the first bubble tube protrusion 314 and the second bubble tube protrusion 316 will deepen, and their fit with the corresponding concave part will be tighter. At the same time, the arc-shaped body of the bubble tube 310 will extend towards the gap on the side of the fixed installation structure 340, and the contact pressure with the sealing surface will be enhanced through greater elastic deformation, so as to maintain reliable water-blocking and sealing performance even under extreme conditions such as high-pressure water flow impact.

[0050] Next, we see the support lip 320, which is disposed on the first fixed connection portion 347 of the fixed mounting structure 340 and consists of a support lip protrusion 321, a support lip recess 322, a support lip top 323, and a support lip connecting portion 324. The support lip protrusion 321 protrudes towards the inner wall of the bubble tube 310. During the wading test, the support lip protrusion 321 will face the impact of the water flow. Figure 10 As can be seen, when the car door is closed to the D0mm assembly position, the top 323 of the support lip abuts against the inner wall of the bubble tube 310.

[0051] Please see Figure 10We performed CAE compression load analysis on the seals. When the door closes, the left sheet metal moves to the right, and the right sheet metal moves downwards. At the D0-2mm assembly position, the fixing lip 345 first contacts the sheet metal surface and triggers deformation. The bubble tube 310 is slightly deformed due to contact with the right sheet metal. At this point, the compression load is recorded as 3.41 N / 100 mm. As the door continues to close to the D0-1mm assembly position, the bubble tube 310 continues to deform. At this point, the bubble tube 310 foams EPDM through its own expansion. The elastic recovery of the material continuously fills the sealing gap, at which point the compressive load is recorded as 4.21 N / 100 mm. When the door is closed to the D0 mm assembly position, the top of the support lip 323 abuts against the inner wall of the foam tube, significantly increasing the load to 5.85 N / 100 mm. This "synergistic abrupt change point" in the stress-displacement curve marks the transition of the sealing structure from a "single component bearing" mode to a "multi-component collaborative bearing" mode. When the door is closed to the D0+1 mm assembly position, the sealing structure resists excessive compression through elastic deformation redundancy, at which point the compressive load is recorded as 10.80 N / 100 mm. The compressive load increases rapidly, which is something that the comparative sealing strip cannot provide. When the door is closed to the D0+2 mm assembly position, the foaming material of the foam tube 310 and the rigidity of the support lip 320 work together, further increasing the load to 16.36 N / 100 mm, verifying the reliability of the water-resistant seal designed in this application.

[0052] In traditional designs, when the door sealing system is in its nominal assembly position (D0 mm), a certain gap is usually reserved between the sealing lip (if present) and the inner wall of the bubble tube 310. However, under over-compression conditions (such as when there are manufacturing tolerances in the door sheet metal or when driving through deep water), the assembly position may dynamically shift to D0+1mm or even D0+2mm. This reserved gap will quickly disappear, and the door and body sheet metal structure will experience unexpected rigid impact, thereby triggering structural vibration and producing knocking sounds, friction sounds, and other abnormal noises that can be clearly perceived by the user. The technical solution proposed in this application optimizes the sealing system structure to ensure that it can form effective pre-compression (begin to contact) with the corresponding contact surface in the nominal assembly state of D0 mm. The sealing strip is transformed from a traditional passive buffer block that only functions under extreme displacement into an active elastic element that continuously provides support and damping. Because a stable contact interface has been established during the static assembly stage, the sealing system can continuously buffer and isolate the relative displacement between the door and the body during vehicle dynamic driving. It converts the energy that might have caused rigid impact into its own elastic potential energy and gradually dissipates it, thus effectively solving the problem of abnormal noise caused by rigid impact.

[0053] Finally, we see the fixed mounting structure 340, which is fixed to the door / body sheet metal by the tape 102 or the buckle 101. The fixed mounting structure 340 includes a first fixed end 341 fixedly connected to the first bubble tube end 311, and a second fixed end 342 fixedly connected to the second bubble tube end 312. The first fixed end 341, the first fixed connecting part 347, the second fixed end 342, and the second fixed connecting part 348 are connected and surround the through hole 330. Further, the first fixed connecting part 347 is provided with a supporting lip. The first fixed connecting part 347 is provided with a fixed inner recess 343 on one side of the supporting lip recess 322. When the bubble tube deforms, the first bubble tube protrusion 314 and / or the second bubble tube protrusion 316 will deform towards this part. The space buffer of the recess prevents the bubble tube protrusion from irreversibly deforming due to excessive compression, while ensuring that the protrusion and the supporting lip recess 322 always remain in contact, maintaining the effective contact pressure of the sealing surface. As a preferred design, a "V"-shaped notch is provided on one side of the second fixed connection part 348. When fixed with the buckle 101, this notch reduces the resistance of the buckle 101 embedding into the through hole 330 through a guiding effect, making the assembly process easier. At the same time, the geometric positioning characteristics of the notch ensure that the buckle 101 or tape 102 is continuously laid along a preset trajectory, avoiding uneven force due to installation misalignment and reducing the risk of local seal failure. A fixed support part 344 is provided on one side of the second fixed connection part 348 to support the sealing strip and cover the buckle 101 or tape 102 inside. The fixed lip 345 formed by the outward extension of the fixed support part 344 pre-deforms towards the fixed outer recess 346 after the sealing strip is installed. The rebound force generated by the deformation continuously adheres to the mounting surface, providing stable auxiliary support for the sealing strip, effectively counteracting the lateral force generated when the bubble tube is compressed, ensuring that the sealing strip as a whole always maintains a precise fit with the vehicle body under complex working conditions, further enhancing the durability and stability of the sealing effect.

[0054] Figure 6 The diagram shows the positions of four cross-sections 300 (AA, BB, CC, DD) relative to the sheet metal, where F represents the direction of the water flow impact. As can be seen from the diagram, the water flow consistently impacts the recessed portion 322 of the supporting lip 320. When the water flows, the bubble tube 310 absorbs and buffers the pressure through elastic deformation, while the supporting lip deforms synchronously. Together, they form a continuous sealing barrier, ensuring that the sealing strip effectively blocks water penetration in various critical locations (roof, hinges, handles, door sills) in wading environments. Finally, wading tests verified the waterproof adaptability of this sealing structure across multiple parts of the vehicle body.

[0055] Figure 7The diagram shows the assembly test process of adding a support lip to a traditional sealing strip and the sheet metal. CAE assembly analysis showed compressive loads of 2.63 N / 100 mm and 4.03 N / 100 mm at the D0 mm assembly position, indicating that even with the support lip design of this application, traditional sealing strips would struggle to achieve satisfactory compressive loads.

[0056] Please see Figure 8 and Figure 9 We conducted CAE water immersion tests on the sealing strip of this application and the comparative sealing strip, and the conclusions are as follows: 1. Comparison of sealing strip (320 design without support lip): When the water pressure rises to 5825Pa, the comparison sealing strip begins to fail and leak.

[0057] 2. Sealing strip of this application: When the water pressure rises to 28660Pa, the sealing strip does not fail (i.e., it meets the 25000Pa water pressure test); when the water pressure is continuously increased until it reaches 145800Pa, the sponge tube 310 is severely deformed and the sealing strip begins to fail.

[0058] Please see Figure 10 CAE analysis revealed that the sealing strip of this application (EPDM sponge adhesive + EPDM solid adhesive) and the comparative sealing strip ( Figure 8 The test results for the compressive load (N / 100mm) of the structure are as follows: Comparison of sealing strips 3.58 4.61 5.62 6.57 7.40 This application's sealing strip 3.41 4.21 5.85 10.80 16.36 Furthermore, we propose a new concept: D0mm is the nominal assembly position, D0-1mm and D0-2mm are under-compression positions, and D0+1mm and D0+2mm are over-compression positions. During the compression process from D0-2mm to the nominal assembly position D0, we refer to the sealing strip as being in the first compression stage (i.e., D0mm, D0-1mm, and D0-2mm). When the vehicle is deeply submerged or the gap between the door and body decreases due to manufacturing tolerances, and the compression of the sealing strip exceeds D0mm, entering an over-compression state of D0+1mm or even D0+2mm, we refer to the sealing strip entering the second compression stage (i.e., D0+1mm and D0+2mm).

[0059] Meanwhile, we define the effective stiffness as the ratio of the change in compressive load (ΔF) to the corresponding change in compressive displacement (Δx) within a selected compression range. Specifically, we select the range from position "D0-1" to position "D0" to calculate the effective stiffness K1, because this range best represents the mechanical behavior of the sealing strip under normal assembly and minor dynamic disturbances; we select the range from position "D0" to position "D0+1" to calculate the effective stiffness K2, because this range is precisely the critical stage where the supporting structure begins to work and the stiffness undergoes a sudden change.

[0060] From the table, we can find that K1 = (5.85 - 4.21) / (1) = 1.64; K2 = (10.80 - 5.85) / (1) = 4.95.

[0061] Based on the table above and the CAE wading test data, the first compression stage primarily involves elastic deformation of the main sealing part, providing the contact pressure required for sealing. The data shows that the compression load of the sealing strip in this application during this stage (3.41 N / 100 mm for D0-2 mm, 4.21 N / 100 mm for D0-1 mm, and 5.85 N / 100 mm for D0 mm) is similar to that of the comparative sealing strip (3.58 N / 100 mm for D0-2 mm, 4.61 N / 100 mm for D0-1 mm, and 5.62 N / 100 mm for D0 mm), ensuring good sealing performance of the vehicle under static and normal operating conditions, while avoiding the problem of deteriorated closing force due to excessive initial pressure. During this stage, the supporting lip of the sealing strip in this application has not yet made effective contact with the body sheet metal or is only in a critical contact state, bearing little or no pressure. The effective stiffness K1 in this stage is relatively low.

[0062] When a vehicle begins deep wading (especially facing wave surges) or the gap between the door and the body decreases due to manufacturing tolerances, the compression of the sealing strip exceeds D0mm, entering an over-compression state of D0+1mm or even D0+2mm, at which point the sealing strip enters the second compression stage. At this point, the support lip of the sealing strip begins to make stable contact with the body sheet metal and undergoes significant elastic deformation, thus working together with the main sealing part to resist external pressure. This additional load-bearing path causes a sharp increase in the effective stiffness K2 of the sealing system.

[0063] When the compression position changes from D0mm to D0+1mm, the compressive load of the sealing strip in this application surges from 5.85N / 100mm to 10.80N / 100mm, and its effective stiffness K2 is 4.95. Compared with the first-stage effective stiffness K1, the second-stage effective stiffness K2 of the sealing strip in this application is approximately 3.0 × K1. In contrast, the compressive load of the comparative sealing strip in the same process only increases from 5.62N / 100mm to 6.57N / 100mm, and its effective stiffness K2 is only 0.95.

[0064] This nonlinear mechanical property is key to the ultra-high water pressure resistance of the sealing strip in this application. As shown in the CAE immersion test results, the comparative sealing strip failed and leaked water under 5825Pa water pressure. This is because when the water pressure increases, the limited and slowly increasing reaction force of the compressive load (the reaction force of the compressive load is numerically equal to the force of the compressive load, but in the opposite direction) is insufficient to resist the pressure of the water on the car door. However, when the sealing strip of this application passively enters the second stage of overcompression under water pressure, its rapidly increasing reaction force of the compressive load (reaching 10.80N / 100mm at D0+1mm and even higher at D0+2mm, reaching 16.36N / 100mm) forms a robust "pressure wall," effectively offsetting the external water pressure and maintaining the integrity of the sealing interface. This allows the sealing strip of this application to easily meet the 25000Pa water pressure test requirement, with an ultimate water pressure resistance of up to 145800Pa, demonstrating better sealing reliability and robustness.

[0065] In summary, this application creatively incorporates a support lip 320 into the fixed mounting structure 340, proposing a novel sealing strip design structure. In this application, the foam tube 310 serves as the main sealing component. Its arc-shaped structure, combined with the elastic properties of the foamed EPDM material, undergoes adaptive deformation under water pressure, tightly adhering to the vehicle body surface to form the first sealing barrier. Simultaneously, the contact between the support lip 320 and the inner wall 310 of the foam tube forms a second line of defense, hindering water penetration. Even with fluctuations in water pressure, this fit maintains effective contact pressure on the sealing surface through deformation adjustment. The fixed mounting structure 340, through its enclosed design, constructs a rigid foundation, ensuring that the sealing component does not shift under water pressure impact. The fixed support 344 further distributes pressure to the vehicle body sheet metal, avoiding localized stress concentration. The fixed inner recess guides the bubble tube to contract in a preset direction when it deforms, which not only prevents structural damage caused by excessive deformation, but also ensures that the bubble tube and the support lip are always in contact through spatial buffering. The pre-deformation of the fixed lip 345 after installation generates a continuous rebound force, which counteracts the lateral force of the bubble tube 310 under pressure. Together with the fixed support 344 to shield and protect the connector, it further enhances the stability of the structure under long-term water pressure, thereby achieving effective resistance to large water pressure.

[0066] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A water barrier weatherstrip for sealing the gap between a vehicle door and a vehicle body, characterized by, include: A fixed mounting structure (340) is used to install the water-blocking sealing strip onto the vehicle body sheet metal, the fixed mounting structure (340) including a first fixed connection part (347). A hollow compression sealing structure (310) is integrally connected with the fixed installation structure (340); A support lip (320) is connected to the first fixed connection part (347) of the fixed installation structure (340) via a support lip connection part (324) and extends into the hollow area of ​​the compression sealing structure (310); The support lip (320) has a support lip protrusion (321) protruding toward the inner wall of the compression sealing structure (310), and a support lip top (323) located at its end. When the compression sealing structure (310) is deformed under pressure to the preset assembly position (D0), the top of the support lip (323) abuts against the inner wall of the compression sealing structure (310) to provide internal support for the compression sealing structure (310).

2. The weatherstrip of claim 1, wherein: The supporting lip (320) also includes a supporting lip recess (322); Furthermore, the inner wall of the compression sealing structure (310) is provided with a first bubble tube protrusion (314) and a second bubble tube protrusion (316) opposite to the support lip recess (322), and a first bubble tube recess (315) and a second bubble tube recess (317) respectively corresponding to the bubble tube protrusion. When the compression sealing structure (310) is compressed, the first bubble tube protrusion (314) and the second bubble tube protrusion (316) undergo complementary contraction deformation in the direction of their corresponding first bubble tube recess (315) and second bubble tube recess (317) to disperse local extrusion stress and avoid sealing failure due to excessive deformation.

3. The weatherstrip of claim 2, wherein: The first fixed connection part (347) is provided with a fixed inner recess (343), which is positioned opposite to the first bubble tube protrusion (314) and / or the second bubble tube protrusion (316) to guide and accommodate the deformation of the bubble tube protrusion when the compression sealing structure (310) is compressed.

4. The weatherstrip of claim 1, wherein: The fixed mounting structure (340) also includes a fixed lip (345) extending therefrom; the fixed lip (345) is configured to pre-deform after installation, thereby generating a continuous rebound force to fit tightly against the mounting surface; the rebound force is used to resist and balance the lateral thrust generated when the compression seal structure (310) is compressed.

5. The weatherstrip of claim 1, wherein: The water-blocking sealing strip has non-linear compression characteristics, wherein, in the first compression stage from the undercompressed state to the preset assembly position (D0), the compression load is generated by the elastic deformation of the compression sealing structure (310). In the second compression stage, when the support lip (320) enters the over-compression state from the preset assembly position, the support lip (320) begins to abut against the inner wall of the compression sealing structure (310) and shares the pressure with the compression sealing structure (310); The effective stiffness K2 of the second compression stage is at least 2.5 times the effective stiffness K1 of the first compression stage.

6. The weatherstrip of claims 1 or 5, wherein: The compressive load of the water-blocking sealing strip at the preset assembly position is 5N / 100mm to 9N / 100mm.

7. The weatherstrip of claim 5 wherein: When the water-blocking sealing strip is compressed from the preset assembly position (D0) to D0+1mm, the resulting increase in compressive load is ≥4.0N / 100mm.

8. The weatherstrip of claims 1 or 5, wherein: The compression sealing structure (310) is EPDM sponge material with a density of 0.65±0.05 g / cm 3 . The fixed mounting structure (340) and the support lip (320) integrally connected therewith are made of EPDM dense rubber or micro-foamed rubber material with a density not less than 0.80 g / cm 3 .

9. A vehicle door, characterized by The device is equipped with a water-blocking sealing strip as described in any one of claims 1-8.

10. An automobile characterized by comprising: The vehicle door is equipped with a water-retaining sealing strip as described in any one of claims 1-8.

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