Back door assembly and vehicle
By setting a hinge reinforcement plate and an expansion reinforcement plate in the hinge area of the back door assembly, the problem of high manufacturing difficulty and cost of the back door assembly in the prior art is solved, and the strength and stiffness are improved, while reducing production difficulty and cost.
Patent Information
- Application Number
- CN202421451254.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-24
- Publication Date
- 2025-02-28
- Estimated Expiration
- 2034-06-24
AI Technical Summary
When the existing back door assembly increases strength and stiffness, it is difficult and costly to manufacture, and the reinforcement plate has a large size and heavy weight, resulting in high operating demand and high cost.
The inner and outer plates that are buckled are installed, and the hinge reinforcement plate and an expansion reinforcement plate are arranged in the cavity surrounded by the inner and outer plates. The hinge reinforcement plate is arranged around the hinge area and is fixedly connected to the inner and outer plates. The expansion reinforcement plate fills the area on the side of the hinge reinforcement plate after being expanded by heat.
The manufacturing difficulty and production cost of the back door assembly are reduced, the strengthening effect of the hinge area is maintained, the NVH performance of the whole vehicle is improved, and the connection structure between the reinforcement plate and the inner plate and the outer plate is optimized.
Smart Images
Figure CN222538635U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of vehicles, in particular to a back door assembly and a vehicle. Background Art
[0002] The tailgate assembly is the opening and closing part at the back of the vehicle body, which is connected to the vehicle body through hinges and door locks to meet the basic opening and closing movements, as well as the support positioning when opening and the sealing when closing. At present, in order to increase the strength, lateral stiffness, droop stiffness and other properties of the tailgate assembly, a reinforcement plate is provided at the hinge position of the tailgate assembly. Two reinforcement plates are symmetrically provided in the width direction of the tailgate assembly, and are effectively connected to the inner plate and the outer plate of the tailgate assembly. Usually, the reinforcement plate is clamped between the inner plate and the outer plate and fixedly connected to both the inner plate and the outer plate. Therefore, a special connection structure design is required, and the tooling cost and assembly difficulty are high. At the same time, the reinforcement plate is usually an upper and lower connecting structure to take root at the bottom of the tailgate assembly to meet the reinforcement of the top hinge area. Therefore, the reinforcement plate is large in size and heavy in weight, which leads to a large weight of the tailgate assembly, a large operating force, and a high cost.
[0003] Therefore, how to reduce the manufacturing difficulty and cost of the tailgate assembly is a technical problem that needs to be solved urgently by those skilled in the art. Utility Model Content
[0004] The utility model provides a back door assembly and a vehicle, so as to reduce the manufacturing difficulty and production cost of the back door assembly and ensure the strengthening effect of the hinge area on the back door assembly.
[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:
[0006] In a first aspect, the utility model provides a tailgate assembly, comprising an inner panel and an outer panel that are installed in a snap-fitting manner, a hinge reinforcement plate and an expansion reinforcement plate that can expand due to heat are arranged in a cavity enclosed by the inner panel and the outer panel, the hinge reinforcement plate is arranged at least around the area where the hinge is arranged on the tailgate assembly and is fixedly connected to the inner panel and the outer panel, the expansion reinforcement plate is fixedly arranged on one side of the hinge reinforcement plate, and the expanded expansion reinforcement plate can fill the area on one side of the hinge reinforcement plate after expansion.
[0007] Optionally, in the above-mentioned tailgate assembly, the expansion reinforcement plate includes a frame, a buckle and an expansion body, the expansion body and the frame are integrally formed to expand when heated, and the buckle is embedded in a mounting hole opened on the frame and is clamped and fixed to the hinge reinforcement plate.
[0008] Optionally, in the above-mentioned tailgate assembly, the buckle includes at least a first buckle and a second buckle, and the size of the first buckle is smaller than that of the second buckle, the first buckle is docked and limited with the positioning hole on the hinge reinforcement plate, and the second buckle is locked and connected with the fixing hole on the hinge reinforcement plate.
[0009] Optionally, in the above-mentioned tailgate assembly, expansion bodies are provided on both sides of the frame facing toward and away from the hinge reinforcement plate, and avoidance holes penetrating the expansion bodies are opened on the frame.
[0010] Optionally, in the above-mentioned tailgate assembly, the expansion body is one or more of foaming materials such as foam plastic, foam rubber, and foam resin.
[0011] Optionally, in the above-mentioned tailgate assembly, the expansion reinforcement plate is arranged on the side of the hinge reinforcement plate facing the inner plate, or the expansion reinforcement plates are arranged on both sides of the hinge reinforcement plate.
[0012] Optionally, in the above-mentioned tailgate assembly, the hinge reinforcement plate and the inner panel are fixedly connected by spot welding, and the expanded reinforcement plate after expansion covers the welding point area on the hinge reinforcement plate.
[0013] Optionally, in the above-mentioned tailgate assembly, two hinge reinforcement plates are symmetrically arranged in the width direction of the tailgate assembly, and the hinge reinforcement plate on one side covers the curved structure area on the inner panel and the outer panel.
[0014] Optionally, in the above-mentioned tailgate assembly, the hinge reinforcement plate is made of high-strength steel, the frame is made of plastic, and the expansion body and the frame are integrally formed through an injection molding process.
[0015] In a second aspect, the utility model further provides a vehicle, wherein the tailgate assembly provided by any one of the above-mentioned embodiments is provided at the rear of the vehicle.
[0016] It can be seen from the above technical scheme that the back door assembly provided by the utility model is provided with a hinge reinforcement plate and an expansion reinforcement plate in the cavity area between the inner plate and the outer plate that are installed in a snap-fitting manner. The hinge reinforcement plate is arranged around the setting area of the hinge and is fixedly connected to both the inner plate and the outer plate to strengthen the rigidity of the area around the hinge, while the expansion reinforcement plate is fixedly arranged on one side of the hinge reinforcement plate. After the installation is completed, the expansion reinforcement plate can expand in volume due to heat to fill the cavity area between the hinge reinforcement plate and the inner wall of the back door assembly. The filling effect can block the cavity on the side of the hinge reinforcement plate, improve the integrity of the hinge reinforcement plate and the inner wall of the back door assembly, and make it easier to transfer load. At the same time, the cavity on the side of the hinge reinforcement plate is isolated to achieve lifting. The purpose of frequency reduction vibration is to block the generation and transmission of resonance sound and play a role in noise reduction. Based on the effect of the expansion reinforcement plate on the improvement of the connection integrity of the hinge reinforcement plate and the tailgate assembly, the size of the hinge reinforcement plate can be reduced while maintaining the original connection effect compared to the prior art. The connection effect of the expansion reinforcement plate on the hinge reinforcement plate can also optimize the partial connection structure between the hinge reinforcement plate and the inner panel and the outer panel, thereby reducing the production difficulty. In addition, the design of the above structure also takes into account the necessary processes for the production of the entire vehicle. The expansion reinforcement plate does not need to be independently heated or processed. Instead, during the process of painting and baking the white body, the expansion reinforcement plate is heated and expanded to complete the cavity filling action, thereby reducing the production difficulty and cost of the tailgate assembly. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the technical solutions in the embodiments of the utility model or the prior art, the drawings required for use in the embodiments or the prior art description are briefly introduced below. Obviously, the drawings described below are only some examples or embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without creative work, and the utility model can also be applied to other similar scenarios based on the provided drawings. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.
[0018] Figure 1 It is a schematic diagram of the structure of a back door assembly without an outer panel in the prior art;
[0019] Figure 2 It is a schematic diagram of the structure of a back door assembly without an outer panel provided by an embodiment of the utility model;
[0020] Figure 3 yes Figure 2 AA section view;
[0021] Figure 4 for Figure 3 A schematic diagram of the structure of the expansion reinforcement plate in the expansion state;
[0022] Figure 5 It is a schematic diagram of the structure of the expansion reinforcement plate;
[0023] Figure 6 yes Figure 5 Bottom view of
[0024] Among them, 10-inner plate; 20-outer plate; 30-hinge reinforcement plate; 40-expansion reinforcement plate; 410-frame; 4110-avoidance hole; 4210-first buckle; 4220-second buckle; 430-expansion body;
[0025] Figure 1 The mark in is the structure in the prior art, wherein: 100-inner plate; 200-reinforcement plate. DETAILED DESCRIPTION
[0026] The load conditions on the hinge area of the tailgate assembly are more complicated, so a reinforcing plate structure is often required to strengthen it in order to maintain the movement stability of the hinge area. The current reinforcing plate structures are mostly fixed by welding, and they need to be adaptively coordinated with the original structure of the tailgate assembly to maintain the structural integrity after assembly. At the same time, they need to have the strength required for reinforcement. Therefore, not only is the structure more complicated, but the size is also larger in order to take root on the opposite side of the tailgate assembly and provide a force transmission path. However, this will lead to increased manufacturing difficulty and cost of the tailgate assembly.
[0027] In order to make the technical personnel in this field better understand the present invention, the embodiments of the present invention are described below with reference to the accompanying drawings. In addition, the embodiments shown below do not limit the contents of the utility model described in the claims. In addition, the entire contents of the structures represented by the following embodiments are not limited to those necessary for the solutions of the utility model described in the claims.
[0028] See also Figure 1 In the prior art, reinforcing plates 200 are provided on both sides of the inner plate 100. Figure 1 As can be seen from the split seam area in the figure, the reinforcing plate 200 needs to extend to the top and bottom areas of the inner plate 100 in the vertical direction to meet its reinforcement requirements. Figure 2-6The back door assembly provided by the embodiment of the utility model includes an inner panel 10 and an outer panel 20 which are snap-fitted and installed as an integral structure, and a hinge reinforcement plate 30 and an expansion reinforcement plate 40 are arranged in the cavity enclosed by the inner panel 10 and the outer panel 20. It should be noted here that the inner panel 10 and the back door assembly are the panel structures on the side facing the vehicle body, and the outer panel 20 is the panel structure on the side facing the external area of the vehicle body. The back door assembly needs to have the ability to rotate to realize the opening and closing function, so it is provided with a hinge structure, and the hinge reinforcement plate 30 is at least arranged around the area where the hinge is set on the back door assembly, and is fixedly connected to both the inner panel 10 and the outer panel 20 to realize the reinforcement of the hinge setting area; and in the above structure, since the inner panel 10 and the outer panel 20 need to meet the styling structure of the whole vehicle, their structure The surface of the structure is a non-flat concave-convex structure. Correspondingly, after the hinge reinforcement plate 30 is connected to the inner panel 10 and the outer panel 20, a cavity structure will exist in the area between the connection ends, which may cause structural weakness and risks such as vibration and wind noise during operation. The expansion reinforcement plate 40 is fixedly arranged on one side of the hinge reinforcement plate 30. The expansion reinforcement plate 40 can expand in volume when heated and fill the area on one side of the hinge reinforcement plate 30 after expansion. After the expansion reinforcement plate 40 is expanded and filled, the hinge reinforcement plate 30 is rooted and connected to the inner wall structure of the tailgate assembly from the side where the expansion reinforcement plate 40 is set, and effective load transfer in the hinge area is realized. At the same time, the filling effect of the expansion reinforcement plate 40 fills the cavity on the side of the hinge reinforcement plate 30, reduces vibration noise and wind noise, and can improve the NVH performance of the entire vehicle.
[0029] As for the expansion action of the expansion reinforcement plate 40, during the production process of the tailgate assembly, the setting area of the expansion reinforcement plate 40 can be directly heated to achieve the expansion and filling of the expansion reinforcement plate 40. More preferably, considering the production process of the whole vehicle, during the production process of the tailgate assembly, after the inner panel 10, the outer panel 20, the hinge reinforcement plate 30 and the expansion reinforcement plate 40 are assembled and connected into an integrated structure, there is no need to further process the expansion reinforcement plate 40. In the subsequent process, the tailgate assembly needs to be installed on the body frame 410 to form a complete body-in-white structure. When the body-in-white is in the process of painting and baking, the expansion reinforcement plate 40 will expand due to the heat to complete the cavity filling action between the hinge reinforcement plate 30 and the inner wall of the tailgate assembly.
[0030] The back door assembly provided by the embodiment of the utility model is provided with a hinge reinforcement plate 30 and an expansion reinforcement plate 40 in the cavity area between the inner panel 10 and the outer panel 20 which are installed in a snap-fitting manner. The hinge reinforcement plate 30 is arranged around the setting area of the hinge and is fixedly connected to both the inner panel 10 and the outer panel 20 to strengthen the rigidity of the area around the hinge, while the expansion reinforcement plate 40 is fixedly arranged on one side of the hinge reinforcement plate 30. After installation, the expansion reinforcement plate 40 can expand in volume due to heat to fill the cavity area between the hinge reinforcement plate 30 and the inner wall of the back door assembly. The filling effect can block the cavity on the side of the hinge reinforcement plate 30, improve the integrity of the hinge reinforcement plate 30 and the inner wall of the back door assembly, and make it easier to transfer load. At the same time, the cavity on the side of the hinge reinforcement plate 30 is isolated to achieve frequency conversion. The purpose of vibration reduction is to block the generation and transmission of resonance sound and play a role in noise reduction. Based on the improvement effect of the expansion reinforcement plate 40 on the connection integrity of the hinge reinforcement plate 30 and the tailgate assembly, compared with the prior art, the size of the hinge reinforcement plate 30 can be reduced and the original connection effect can be maintained. The connection effect of the expansion reinforcement plate 40 on the hinge reinforcement plate 30 can also optimize the partial connection structure between the hinge reinforcement plate 30 and the inner panel 10 and the outer panel 20, thereby reducing the production difficulty. In addition, the design of the above structure also takes into account the necessary processes for the production of the entire vehicle. The expansion reinforcement plate 40 does not need to be independently heated or processed. Instead, during the process of painting and baking the white body, the expansion reinforcement plate 40 is heated and expanded to complete the cavity filling action, thereby reducing the production difficulty and cost of the tailgate assembly.
[0031] Furthermore, in some embodiments of the present invention, the expansion reinforcement plate 40 is mainly composed of a skeleton 410, a buckle and an expansion body 430, wherein the skeleton 410 is a basic bearing structure, and the expansion body 430 is fixedly arranged on the skeleton 410, so as to expand in a direction away from the skeleton 410 when heated to complete the filling action, and it should be noted that the expansion body 430 is preferably integrally formed with the skeleton 410 to maintain a stable connection effect between the two and to prevent the expansion body 430 from slipping on the surface of the skeleton 410 when expansion occurs; and the buckle is embedded in the mounting hole opened on the skeleton 410, and the locking end of the buckle is clamped and fixed to the corresponding hole on the hinge reinforcement plate 30 to achieve a stable connection effect and reduce the difficulty of assembly.
[0032] In order to improve the assembly convenience of the expansion reinforcement plate 40 while maintaining the connection effect between the expansion reinforcement plate 40 and the hinge reinforcement plate 30, at least two buckles of different sizes are provided in the back door assembly provided in the embodiment of the utility model. Specifically, the buckles include at least a first buckle 4210 and a second buckle 4220, and the size of the first buckle 4210 is smaller than the second buckle 4220, so that during the assembly process, the expansion reinforcement plate 40 can only be aligned and connected with the hinge reinforcement plate 30 in a single posture, thereby avoiding To avoid the risk of wrong installation, specifically, the first buckle 4210 is docked with the positioning hole on the hinge reinforcement plate 30 to realize the pre-installation limit function, and the second buckle 4220 is locked and connected with the fixing hole on the hinge reinforcement plate 30. After the first buckle 4210 is aligned, the docking process of the second buckle 4220 in the fixing hole is easier to achieve. At the same time, when locking the second buckle 4220, due to the limiting effect of the first buckle 4210, the expansion reinforcement plate 40 will not rotate, which prompts the convenience of the assembly process.
[0033] It should be noted that, depending on the setting area of the expansion reinforcement plate 40, if the area that the expansion reinforcement plate 40 needs to cover and fill is too large, the number of the buckle structures can be increased appropriately.
[0034] In order to ensure the filling effect of the expansion reinforcement plate 40 on the cavity area after expansion, in some embodiments of the utility model, in the expansion reinforcement plate 40, expansion bodies 430 are provided on both sides of the skeleton 410 facing and facing away from the hinge reinforcement plate 30. The expansion bodies 430 on the side of the skeleton 410 facing the hinge reinforcement plate 30 can expand and fill the gap area between the skeleton 410 and the hinge reinforcement plate 30 when heated, while the expansion bodies 430 on the side of the skeleton 410 facing away from the hinge reinforcement plate 30 expand and fill the area between the skeleton 410 and the inner wall of the tailgate assembly when heated. The expansion bodies 430 on both sides cooperate to achieve good filling between the hinge reinforcement plate 30 and the inner wall of the tailgate assembly. Compared with the expansion body 430 provided on one side to extend to the entire cavity area through one-sided expansion, the expansion bodies 430 on both sides can be butted and pressed after expansion, and the filling effect is more compact and effective.
[0035] It should also be noted that in order to avoid the influence of the assembly sequence on the assembly effect, an avoidance hole 4110 is also opened on the skeleton 410 structure of the expansion reinforcement plate 40 for the passage of mounting structures such as pins, and the avoidance hole 4110 runs through the expansion body 430 at the corresponding position. The expansion body 430 is set in the setting area of the avoidance hole 4110, and the gap structure in the avoidance hole 4110 can be filled after the expansion body 430 expands due to heat, thereby reducing the risk of gaps in the avoidance hole 4110 area.
[0036] Furthermore, in order to ensure the reinforcing effect of the hinge reinforcement plate 30 on the hinge setting area, in some embodiments of the present invention, the hinge reinforcement plate 30 is made of high-strength steel to ensure the stability and strength of the tailgate assembly when subjected to large external forces. At the same time, in order to meet the lightweight requirements of the vehicle, the skeleton 410 of the expansion reinforcement plate 40 is made of plastic material to have a lightweight and easy to process effect. On this basis, the expansion body 430 can be integrally formed with the skeleton 410 through an injection molding process, which not only improves the production efficiency of the expansion reinforcement plate 40, but also ensures the close combination effect between the expansion body 430 and the skeleton 410, thereby avoiding slippage of the connection surface between the expansion body 430 and the skeleton 410 during the expansion process.
[0037] On the basis of the above-mentioned embodiment, the expansion body 430 can adopt a foaming material, such as a mixture of one or more of foam plastics, foam rubber or foam resin, etc. These materials are light, highly elastic and have good cushioning properties, and can achieve good filling of cavities and gaps, thereby improving the carrying capacity of the tailgate assembly, and also provide excellent cushioning and protection performance, thereby extending the service life of the tailgate assembly.
[0038] In the tailgate assembly provided in the above-mentioned embodiment, the expansion reinforcement plate 40 is provided for filling and reinforcing the periphery of the hinge reinforcement plate 30 to ensure the reinforcing effect of the hinge reinforcement plate 30 on the hinge setting area. In the design process of the tailgate assembly, the hinge reinforcement plate 30 is usually used to reinforce the hinge structure in the inner panel 10 area. Therefore, in some embodiments of the present invention, the expansion reinforcement plate 40 is provided on the side of the hinge reinforcement plate 30 facing the inner panel 10 to fill the cavity area between the hinge reinforcement plate 30 and the inner panel 10. At the same time, it should be noted that when the vehicle weight and cost meet the standards, In the case of a high noise reduction requirement for the entire vehicle, expansion reinforcement plates 40 may be respectively provided on both sides of the hinge reinforcement plate 30, i.e., the side facing the inner panel 10 and the side facing the outer panel 20, so that the expansion reinforcement plate 40 can fill the cavity area between the hinge reinforcement plate 30 and the inner panel 10, as well as the cavity area between the hinge reinforcement plate 30 and the outer panel 20 after expansion. In the area where the hinge reinforcement plate 30 is provided in the tailgate assembly, the hinge reinforcement plate 30 is in contact with both the inner panel 10 and the outer panel 20, which can further enhance its reinforcement effect and reduce noise problems such as resonance and wind noise.
[0039] It should be further explained that, considering that the existing reinforcement plate structure has a large number of exposed welding points after being welded and fixed to the two side panels, which affects the aesthetics of the vehicle, in the tailgate assembly provided in the embodiment of the utility model, the hinge reinforcement plate 30 and the inner panel 10 are fixedly connected by spot welding to ensure the connection effect. At the same time, the design position of the welding point is located in the area of the hinge reinforcement plate 30 that needs to be expanded and filled by the expansion reinforcement plate 40, so that the expanded expansion reinforcement plate 40 covers the welding point area on the hinge reinforcement plate 30, which can not only cover the welding point to improve the aesthetics of the whole vehicle, but also form a protective layer on the surface of the welding point, thereby reducing the risk of corrosion or damage to the welding point due to long-term use or environmental factors.
[0040] Furthermore, in combination with the general design structure of the tailgate assembly, in an embodiment of the utility model, two hinge reinforcement plates 30 are symmetrically arranged in the width direction of the tailgate assembly, that is, the width direction of the vehicle body, which can not only strengthen the protection of the hinges on both sides, but the symmetrically designed structure can also balance the force on the tailgate assembly and reduce deformation or damage caused by uneven force. At the same time, combined with the structure of the tailgate assembly, the extended length of the single-sided hinge reinforcement plate 30 covers the curved structure area on the inner panel 10 and the outer panel 20, so as to effectively strengthen the curved area where the load transfer is complex and prone to stress concentration, thereby reducing the failure risk of the tailgate assembly.
[0041] In addition, an embodiment of the utility model further provides a vehicle, which is provided with a tailgate assembly provided by any of the above-mentioned embodiments at the rear of the vehicle. Since the tailgate assembly has the technical effects provided by the previous embodiments, the vehicle also has the above-mentioned technical effects, which will not be repeated herein; it should be noted that the vehicle can be a gasoline vehicle, an electric vehicle or a hybrid vehicle, etc.
[0042] It should be noted that, for the convenience of description, only the parts related to the utility model are shown in the drawings. In the absence of conflict, the embodiments and features in the embodiments of the utility model can be combined with each other.
[0043] As shown in the utility model and claims, unless the context clearly indicates an exception, the words "a", "an", "a kind" and / or "the" do not specifically refer to the singular, but may also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of clearly identified steps and elements, and these steps and elements do not constitute an exclusive list, and the method or device may also include other steps or elements. The elements defined by the sentence "includes a..." do not exclude the existence of other identical elements in the process, method, commodity or device that includes the elements.
[0044] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.
[0045] The above description is only a preferred embodiment of the utility model and an explanation of the technical principles used, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. The scope of the utility model involved in the utility model is not limited to the technical solution formed by a specific combination of the above-mentioned technical features, but also should cover other technical solutions formed by any combination of the above-mentioned technical features or their equivalent features without departing from the concept of the above-mentioned utility model. For example, the above-mentioned features are replaced with the technical features with similar functions disclosed in the utility model (but not limited to) to form a technical solution.
Claims
1. A back door assembly, characterized in that: It includes an inner panel and an outer panel that are installed in a snap-fitting manner, and a hinge reinforcement plate and an expansion reinforcement plate that can expand due to heat are arranged in a cavity enclosed by the inner panel and the outer panel. The hinge reinforcement plate is arranged at least around the area where the hinge is arranged on the tailgate assembly and is fixedly connected to the inner panel and the outer panel. The expansion reinforcement plate is fixedly arranged on one side of the hinge reinforcement plate, and the expanded expansion reinforcement plate can fill the area on one side of the hinge reinforcement plate after expansion.
2. The back door assembly according to claim 1, characterized in that: The expansion reinforcement plate includes a frame, a buckle and an expansion body. The expansion body is integrally formed with the frame to expand when heated. The buckle is embedded in a mounting hole provided on the frame and is clamped and fixed to the hinge reinforcement plate.
3. The back door assembly according to claim 2, characterized in that: The buckle includes at least a first buckle and a second buckle, and the size of the first buckle is smaller than that of the second buckle. The first buckle is docked and limited with the positioning hole on the hinge reinforcement plate, and the second buckle is locked and connected with the fixing hole on the hinge reinforcement plate.
4. The back door assembly according to claim 2, characterized in that: The expansion bodies are arranged on both sides of the frame facing toward and away from the hinge reinforcement plate, and avoidance holes penetrating through the expansion bodies are opened on the frame.
5. The back door assembly according to claim 2, characterized in that: The expansion body is one or more of foaming materials such as foam plastic, foam rubber, and foam resin.
6. The back door assembly according to claim 1, characterized in that: The expansion reinforcement plate is arranged on a side of the hinge reinforcement plate facing the inner plate, or the expansion reinforcement plates are arranged on both sides of the hinge reinforcement plate.
7. The back door assembly according to claim 6, characterized in that: The hinge reinforcement plate is fixedly connected to the inner plate by spot welding, and the expanded reinforcement plate covers the welding point area on the hinge reinforcement plate after expansion.
8. The back door assembly according to claim 1, characterized in that: The two hinge reinforcement plates are symmetrically arranged in the width direction of the back door assembly, and the hinge reinforcement plate on one side covers the curved structure area on the inner panel and the outer panel.
9. The back door assembly according to claim 2, characterized in that: The hinge reinforcement plate is made of high-strength steel, the frame is made of plastic, and the expansion body and the frame are integrally formed through an injection molding process.
10. A vehicle, characterized in that: A tailgate assembly as claimed in any one of claims 1 to 9 is arranged at the rear of the vehicle.