Battery cell mounting structure, battery pack and vehicle

Abstract

The utility model relates to a battery cell mounting structure, a battery pack and a vehicle. The battery cell mounting structure comprises a battery cell assembly and a battery bottom upper-layer plate, and the battery cell assembly and the battery bottom upper-layer plate are bonded and fixed through glue; the battery cell assembly comprises at least two battery cells, and a concentric-square-shaped buffer pad is arranged between every two adjacent battery cells. The utility model further provides a battery pack which comprises the battery cell mounting structure disclosed by the utility model. The utility model further provides a vehicle which comprises the battery pack provided by the utility model. According to the utility model, the problems that the existing battery pack is heavy in weight, not beneficial to integration, complex in process and high in production cost are solved, and the problems that the existing battery pack is low in vibration resistance and collision resistance are also solved.

Description

Technical Field

[0001] This utility model relates to the field of battery pack technology, specifically to a cell mounting structure, a battery pack, and a vehicle. Background Technology

[0002] To meet the power requirements of new energy vehicles, power batteries typically employ a series-parallel integration of multiple cells to ensure the necessary rated voltage and current are supplied to the vehicle's internal components. However, during the daily use of new energy vehicles, power battery packs inevitably suffer from collisions, compression, vibrations, and cell expansion. Therefore, ensuring the quality stability of power batteries during use has become a focus of attention for many researchers and scholars.

[0003] Existing technology discloses a fixing steel strip for power batteries, which consists of a first steel strip and a second steel strip. The second steel strip is located outside the first steel strip and spliced ​​with it to form a square structure. Connecting structures are distributed on both steel strips, their number corresponding to the number of snap-fit ​​slots and snap-fit ​​blocks. The second steel strip has multiple snap-fit ​​slots, with a return spring on one side of each slot, while the first steel strip is connected to corresponding snap-fit ​​blocks. The snap-fit ​​slots and snap-fit ​​blocks are connected by snap-fit. This structure, secured by two steel strips through a connecting mechanism and Velcro, effectively solves the problems of complex and time-consuming steel strip connections in traditional fixing methods. Although this structure improves the vibration and impact resistance of the battery cell assembly by modifying the structure of the cell assembly fixing device, it leads to an increase in the weight and production cost of the power battery pack. Furthermore, the added devices and components complicate the manufacturing process, hindering the integration of the power battery pack and thus affecting its production efficiency. Utility Model Content

[0004] In view of this, the purpose of this utility model is to provide a battery cell mounting structure, a battery pack and a vehicle, so as to solve the problems of existing battery packs, such as large weight, difficulty in integration, complex process and high production cost, and can also solve the problems of low vibration resistance and collision performance of existing battery packs.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] A battery cell mounting structure includes a battery cell assembly and a bottom upper plate of the battery, wherein the battery cell assembly and the bottom upper plate of the battery are fixed together by adhesive; the battery cell assembly includes at least two battery cells, and a U-shaped buffer pad is provided between adjacent battery cells.

[0007] Based on the aforementioned technical methods, by using adhesive bonding to fix the cell assembly and the bottom upper plate of the battery, not only is the weight of the battery pack effectively reduced, meeting the requirements for lightweight design, but the displacement of the cell assembly during use is also effectively prevented, improving the overall structural stability. Furthermore, the assembly process of the cell assembly and the bottom upper plate is simplified, increasing assembly efficiency and reducing production costs. Simultaneously, the use of U-shaped buffer pads between adjacent cells absorbs and disperses vibrations generated during charging and discharging, reducing friction and collisions between cells and effectively extending their lifespan. The ingenious combination of adhesive bonding and U-shaped buffer pads effectively prevents cell displacement or damage when subjected to external impacts, thereby improving the overall safety performance of the battery. This effectively solves the problems of existing battery packs, such as large weight, difficulty in integration, complex processes, and high production costs, and also addresses the issues of low vibration and impact resistance in existing battery packs.

[0008] Preferably, a bottom buffer pad is provided between the cell assembly and the bottom upper plate of the battery.

[0009] By placing a bottom buffer pad between the battery cell assembly and the upper bottom plate of the battery, the bottom buffer pad can absorb and disperse the impact force that the battery cell assembly may be subjected to during transportation or use, thereby reducing damage to the battery cell assembly and improving its stability. The bottom buffer pad effectively reduces friction and collision between the battery cell assembly and the upper bottom plate caused by vibration, enhancing the battery's shock resistance and extending its lifespan. Simultaneously, the bottom buffer pad typically has a certain degree of heat insulation, reducing heat transfer to the battery cell assembly, which is beneficial for battery heat dissipation and helps maintain the battery's normal operating temperature. The presence of the bottom buffer pad prevents the battery cell assembly from directly contacting the upper bottom plate of the battery when subjected to external impact, avoiding short circuits or damage to the internal battery structure, thereby reducing safety risks and improving battery safety.

[0010] Preferably, the battery cell assembly has a front expansion beam at one end and a rear expansion beam at the other end.

[0011] By incorporating a front expansion beam at one end and a rear expansion beam at the other, the battery cell assembly can better distribute pressure when subjected to external forces, thereby enhancing the overall structural stability. During charging and discharging, the battery cell undergoes thermal expansion. The front and rear expansion beams provide sufficient space for the cell to accommodate this expansion, preventing internal stress concentration caused by expansion and extending the cell's lifespan. The expansion beams at both ends simplify the installation process, facilitating the fixing and removal of the cells within the battery pack and improving installation efficiency. Furthermore, the expansion beams effectively absorb and disperse expansion forces when abnormal cell expansion occurs, reducing the risk of cell damage and thus improving the safety performance of the battery pack.

[0012] Preferably, the battery cell assembly is assembled and fixed together with the front expansion beam and the rear expansion beam via connectors.

[0013] By using connectors to secure the battery cell assembly to the expansion beam, displacement of the cells due to vibration or impact during use can be effectively prevented, thus ensuring the overall stability of the battery pack. When maintenance or replacement of the battery cell assembly is required, the connectors allow for quick disassembly and installation, simplifying the maintenance process and improving efficiency. In addition to securing the battery cell assembly, the connectors may also act as heat conductors, helping to transfer the heat generated by the cells to the expansion beam, thereby enhancing heat dissipation and extending the lifespan of the cells.

[0014] The connectors are bolts or clips, which facilitate installation, disassembly, and maintenance.

[0015] Preferably, the battery cell assembly has a left beam on one side and a right beam on the other side.

[0016] By incorporating a left beam on one side and a right beam on the other, the battery cell assembly is effectively supported and secured, preventing displacement or deformation during use. The left and right beams allow for easy fixation of the battery cell assembly in its designated mounting position, while also facilitating quick disassembly and replacement when needed. The presence of these beams provides additional protection for the battery cell assembly, reducing damage from external impacts or pressures and enhancing its protective function. Furthermore, the structural design of the left and right beams helps create good airflow channels, promoting heat dissipation and improving overall thermal performance, thus extending the battery cell's lifespan.

[0017] Preferably, a U-shaped buffer frame is provided between the battery cell assembly and the front expansion beam, the rear expansion beam, the left beam, and the right beam.

[0018] The U-shaped buffer frame design provides an additional support framework for the battery cell assembly, enhancing the overall structural stability of the battery module and preventing displacement or damage when subjected to external impacts or vibrations. The U-shaped buffer frame is typically made of highly elastic materials such as rubber or silicone, forming an effective buffer layer between the battery cell assembly and the surrounding structure. This absorbs and disperses impact forces, protecting the battery cell assembly from damage. The U-shaped buffer frame design also optimizes the heat dissipation of the battery module to some extent. By increasing the contact area between the battery cell assembly and the surrounding environment, heat conduction efficiency is improved, helping to reduce the operating temperature of the battery cell assembly and extend battery life. The introduction of the U-shaped buffer frame makes the installation of the battery cell assembly and the surrounding structure easier and also provides greater convenience for subsequent maintenance operations. For example, when it is necessary to replace a battery cell assembly, it can be more easily removed from the buffer frame, reducing maintenance costs and time.

[0019] Preferably, the adhesive is a structural adhesive.

[0020] Structural adhesives possess high bonding strength, ensuring stable positioning of the battery cell under various operating conditions and reducing displacement caused by vibration or impact. They typically exhibit good temperature resistance, maintaining adhesion over a wide temperature range to meet the usage requirements of the battery cell in different ambient temperatures. Structural adhesives also possess a degree of flexibility, absorbing some stress when the battery cell is under load, reducing internal stress caused by thermal expansion or contraction. The curing time of structural adhesives can be adjusted as needed, facilitating control of installation time during production and improving efficiency. Structural adhesives provide excellent insulation properties, preventing short circuits or leakage during use and enhancing battery cell safety. The use of structural adhesives simplifies the battery cell installation process, reduces reliance on other auxiliary fasteners, and lowers overall costs.

[0021] Preferably, an X-shaped structural adhesive is applied between the cell assembly and the bottom upper plate of the battery to ensure a stable bond.

[0022] Preferably, the surface of the battery cell assembly is connected to a current collector connecting piece.

[0023] Preferably, the current collector connecting piece is fixed to the surface of the battery cell by laser welding.

[0024] Laser welding offers highly precise control over welding position and dimensions, reducing the heat-affected zone on the battery cell surface. Its high welding speed allows for rapid connection of the current collector connector to the cell surface. Laser welding produces high-strength, reliable welds, contributing to improved cell stability and lifespan. The low heat input minimizes thermal damage to the cell material, helping to maintain its performance. Laser welding is easily automated, increasing production efficiency and reducing labor costs. Furthermore, the process generates less smoke and radiation, minimizing environmental impact and meeting modern industrial environmental requirements.

[0025] This utility model also provides a battery pack, including the battery cell mounting structure described in this utility model.

[0026] This utility model also provides a vehicle including the battery pack described in this utility model.

[0027] Preferably, the vehicle is a new energy vehicle.

[0028] The beneficial effects of this utility model are:

[0029] This utility model's battery cell mounting structure, by using adhesive bonding to fix the battery cell assembly and the bottom upper plate of the battery, not only effectively reduces the weight of the battery pack, meeting lightweight requirements, but also effectively prevents displacement of the battery cell assembly during use, improving the overall structural stability. Furthermore, it effectively simplifies the assembly process of the battery cell assembly and the bottom upper plate of the battery, improving assembly efficiency and reducing production costs. Simultaneously, the U-shaped buffer pads placed between adjacent battery cells absorb and disperse vibrations generated during charging and discharging, reducing friction and collisions between cells and effectively extending their service life. The ingenious combination of adhesive bonding and U-shaped buffer pads effectively prevents displacement or damage to the battery cells when subjected to external impacts, thereby improving the overall safety performance of the battery. It also has the advantages of simple structure, easy assembly, and low cost, making it valuable for widespread application in the field of battery pack technology. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the battery cell mounting structure of this utility model;

[0031] Figure 2 This is an exploded view of the battery cell mounting structure of this utility model;

[0032] Figure 3 This is a cross-sectional schematic diagram of the battery cell mounting structure of this utility model;

[0033] Figure 4 This is a schematic diagram of the structure of a loop-shaped buffer frame;

[0034] Among them, 1-cell assembly; 2-bottom upper plate of battery; 3-adhesive; 4-U-shaped buffer pad; 5-bottom buffer pad; 6-front expansion beam; 7-rear expansion beam; 8-connector; 9-left beam; 10-right beam; 11-U-shaped buffer frame. Detailed Implementation

[0035] The embodiments of this utility model will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. It should be understood that the preferred embodiments are only for illustrating this utility model and not for limiting the scope of protection of this utility model.

[0036] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0037] Numerous details are explored in the following description to provide a more thorough explanation of embodiments of this application; however, it will be apparent to those skilled in the art that embodiments of this application may be implemented without these specific details. Example

[0038] like Figures 1 to 4 As shown, a battery cell mounting structure includes a battery cell assembly 1 and a battery bottom upper plate 2. The battery cell assembly 1 and the battery bottom upper plate 2 are bonded and fixed together by adhesive 3. The battery cell assembly 1 includes at least two battery cells, and a U-shaped buffer pad 4 is provided between adjacent battery cells.

[0039] By applying adhesive technology to secure the battery cell assembly to the bottom upper plate of the battery, the weight of the battery pack is significantly reduced, meeting the requirements for lightweight design. This also effectively prevents cell displacement during use, enhancing the overall structural stability. Furthermore, adhesive technology simplifies the assembly process between the cell assembly and the bottom upper plate, improving assembly efficiency and reducing production costs. Simultaneously, the use of U-shaped buffer pads between adjacent cells absorbs and disperses vibrations generated during charging and discharging, reducing friction and collisions between cells and effectively extending their lifespan. This ingenious combination of adhesive bonding and U-shaped buffer pads further prevents cell displacement or damage when subjected to external impacts, significantly improving the overall safety performance of the battery.

[0040] In some embodiments, in order to absorb and disperse the impact forces that the battery cell assembly may be subjected to during transportation or use, thereby reducing damage to the battery cell assembly and improving its stability, a bottom buffer pad 5 is provided between the battery cell assembly 1 and the bottom upper plate 2 of the battery.

[0041] Meanwhile, the bottom buffer pad 5 effectively reduces friction and collision between the battery cell assembly and the upper bottom plate of the battery caused by vibration, enhancing the battery's shock resistance and extending its lifespan. Furthermore, the bottom buffer pad 5 typically has some heat insulation properties, reducing heat transfer to the battery cell assembly and facilitating heat dissipation, thus helping to maintain the battery's normal operating temperature. The presence of the bottom buffer pad 5 also prevents the battery cell assembly from directly contacting the upper bottom plate of the battery when subjected to external impact, avoiding short circuits or damage to the battery's internal structure, thereby reducing safety risks and improving battery safety.

[0042] In some embodiments, in order to better disperse pressure when the cell assembly 1 is subjected to external forces, thereby enhancing the stability of the overall structure, a front expansion beam 6 is provided at one end of the cell assembly 1 and a rear expansion beam 7 is provided at the other end.

[0043] Because the battery cell assembly 1 undergoes thermal expansion during actual charging and discharging, the design of the front expansion beam 6 and the rear expansion beam 7 provides sufficient space for the battery cell assembly 1 to accommodate thermal expansion, avoiding internal stress concentration caused by expansion and thus extending the battery cell's lifespan. The design of the front expansion beam 6 and the rear expansion beam 7 also helps to effectively absorb and disperse expansion forces when the battery cell assembly 1 experiences abnormal expansion, reducing the risk of battery cell damage and thus improving the safety performance of the battery pack.

[0044] The front expansion beam 6 and the rear expansion beam 7 are located at both ends of the cell assembly 1 in the X direction.

[0045] In some embodiments, in order to effectively prevent the cell assembly 1 from shifting due to vibration or impact during use, thereby ensuring the overall stability of the battery pack, the cell assembly 1 is assembled and fixed together with the front expansion beam 6 and the rear expansion beam 7 using connectors 8.

[0046] When the battery cell assembly requires maintenance or replacement, it can be quickly disassembled and installed via connector 8, simplifying the maintenance process and improving maintenance efficiency. Furthermore, connector 8, while securing the battery cell assembly, also plays a role in heat conduction, helping to transfer the heat generated by the battery cell to the expansion beam, thereby enhancing heat dissipation and extending the battery cell's lifespan.

[0047] Among them, connector 8 is a bolt or clip, etc., for easy installation, disassembly and maintenance. Hex head bolts can be used.

[0048] To ensure insulation performance and prevent battery pack leakage, insulating film or insulating paint is applied to the surfaces of connector 8, cell assembly 1, front expansion beam 6 and rear expansion beam 7.

[0049] In some embodiments, in order to effectively support and fix the battery cell assembly and prevent displacement or deformation during use, a left beam 9 is provided on one side of the battery cell assembly 1 and a right beam 10 is provided on the other side. The design of the left beam 9 and the right beam 10 allows the battery cell assembly 1 to be easily fixed in the corresponding installation position, and also facilitates quick disassembly and replacement when needed.

[0050] Furthermore, the presence of the left beam 9 and the right beam 10 provides additional protection for the battery cell assembly, reducing damage to the battery cells from external impacts or pressures and enhancing the protective function of the battery cell assembly. At the same time, the structural design of the left beam 9 and the right beam 10 helps to create good air circulation channels, which is beneficial for the heat dissipation of the battery cell assembly 1, improves the overall heat dissipation performance, and extends the service life of the battery cells.

[0051] The left beam 9 and the right beam 10 are located at both ends of the cell assembly 1 in the Y direction.

[0052] In some embodiments, in order to provide an additional support frame for the cell assembly to enhance the structural stability of the entire battery module and prevent the cell assembly from being displaced or damaged when subjected to external impact or vibration, a U-shaped buffer frame 11 is provided between the cell assembly 1 and the front expansion beam 6, the rear expansion beam 7, the left beam 9 and the right beam 10.

[0053] U-shaped buffer frames are typically made of highly elastic materials such as rubber and silicone. They form an effective buffer layer between the battery cell assembly and the surrounding structure, absorbing and dispersing impact forces to protect the battery cell assembly from damage. Simultaneously, the U-shaped buffer frame design can also optimize the heat dissipation of the battery module to some extent. By increasing the contact area between the battery cell assembly and the surrounding environment, heat conduction efficiency is improved, which helps to reduce the operating temperature of the battery cell assembly and extend the battery's lifespan.

[0054] For example, structural adhesive is selected as adhesive 3.

[0055] Structural adhesives possess high bonding strength, ensuring stable positioning of the battery cell under various operating conditions and reducing displacement caused by vibration or impact. They typically exhibit good temperature resistance, maintaining adhesion over a wide temperature range to meet the usage requirements of the battery cell in different ambient temperatures. Structural adhesives also possess a degree of flexibility, absorbing some stress when the battery cell is under load, reducing internal stress caused by thermal expansion or contraction. The curing time of structural adhesives can be adjusted as needed, facilitating control of installation time during production and improving efficiency. Structural adhesives provide excellent insulation properties, preventing short circuits or leakage during use and enhancing battery cell safety. The use of structural adhesives simplifies the battery cell installation process, reduces reliance on other auxiliary fasteners, and lowers overall costs.

[0056] For example, an X-shaped structural adhesive is applied between the cell assembly 1 and the bottom upper plate 2 of the battery to ensure a strong bond.

[0057] In some embodiments, a current collector connecting piece is connected to the surface of the battery cell assembly 1.

[0058] For example, the current collector connector is fixed to the surface of the battery cell by laser welding.

[0059] Laser welding offers highly precise control over welding position and dimensions, reducing the heat-affected zone on the battery cell surface. Its high welding speed allows for rapid connection of the current collector connector to the cell surface. Laser welding produces high-strength, reliable welds, contributing to improved cell stability and lifespan. The low heat input minimizes thermal damage to the cell material, helping to maintain its performance. Laser welding is easily automated, increasing production efficiency and reducing labor costs. Furthermore, the process generates less smoke and radiation, minimizing environmental impact and meeting modern industrial environmental requirements.

[0060] In actual assembly, a specified number of cells are first arranged in series and parallel order, and a U-shaped buffer pad 4 is placed between adjacent cells. Then, CCS (current collector connecting piece) is connected to the cell surface by laser welding to form cell assembly 1. Then, cell assembly 1 is placed into the battery pack box by tooling fixture. X-shaped structural adhesive is applied to the bottom upper plate 2 of the battery, and bottom buffer pad 5 is placed on the bottom upper plate 2 of the battery at the same time to bond cell assembly 1 to the bottom upper plate 2 of the battery. Then, cell assembly 1 is fixed to the front expansion beam 6 and the rear expansion beam 7 by hexagonal head bolts to obtain the cell installation structure.

[0061] In some embodiments, a battery pack is also provided, including the cell mounting structure of any of the above embodiments.

[0062] In some embodiments, a vehicle is also provided, including the battery pack of any of the above embodiments.

[0063] In summary, the battery cell installation structure of this utility model, by using adhesive bonding to fix the battery cell assembly and the bottom upper plate of the battery, not only effectively reduces the weight of the battery pack, meeting the requirements for lightweight design, but also effectively prevents displacement of the battery cell assembly during use, improving the overall structural stability. Furthermore, it effectively simplifies the assembly process of the battery cell assembly and the bottom upper plate of the battery, improving assembly efficiency and reducing production costs. Simultaneously, the U-shaped buffer pads placed between adjacent battery cells absorb and disperse vibrations generated during charging and discharging, reducing friction and collisions between cells and effectively extending their service life. The ingenious combination of adhesive bonding and U-shaped buffer pads effectively prevents displacement or damage to the battery cells when subjected to external impacts, thereby improving the overall safety performance of the battery. It also has the advantages of simple structure, easy assembly, and low cost, making it valuable for widespread application in the field of battery pack technology.

[0064] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit this application. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.

Claims

1. An installation structure of an electric cell, characterized by comprising: It comprises an electric core assembly (1) and a battery bottom upper layer plate (2), the electric core assembly (1) and the battery bottom upper layer plate (2) are fixed by glue (3).

2. The mounting structure for the battery cell according to claim 1, wherein The electric core assembly (1) and the battery bottom upper layer plate (2) are further provided with a bottom buffer pad (5).

3. The mounting structure for the battery cell according to claim 1, wherein One end of the electric core assembly (1) is provided with a front expansion beam (6), and the other end is provided with a rear expansion beam (7).

4. The mounting structure for the battery cell according to claim 3, wherein The electric core assembly (1), the front expansion beam (6) and the rear expansion beam (7) are fixed together by a connecting piece (8).

5. The mounting structure for the battery cell according to claim 4, wherein One side of the electric core assembly (1) is provided with a left side beam (9), and the other side is provided with a right side beam (10).

6. The mounting structure of the electric cell according to claim 5, wherein The electric core assembly (1), the front expansion beam (6), the rear expansion beam (7), the left side beam (9) and the right side beam (10) are provided with a back type buffer frame (11).

7. The mounting structure of the battery cell according to claim 1, wherein The glue (3) is a structural glue; And / or, the electric core surface of the electric core assembly (1) is connected with a current collector connecting piece.

8. The mounting structure of the electric cell according to claim 7, wherein The current collector connecting piece is fixed on the electric core surface by laser welding.

9. A battery pack, characterized by, It comprises an electric core assembly (1) and a battery bottom upper layer plate (2), the electric core assembly (1) and the battery bottom upper layer plate (2) are fixed by glue (3).

10. A vehicle characterized by comprising: The electric core assembly (1) and the battery bottom upper layer plate (2) are further provided with a bottom buffer pad (5). One end of the electric core assembly (1) is provided with a front expansion beam (6), and the other end is provided with a rear expansion beam (7). The electric core assembly (1), the front expansion beam (6) and the rear expansion beam (7) are fixed together by a connecting piece (8). One side of the electric core assembly (1) is provided with a left side beam (9), and the other side is provided with a right side beam (10). The electric core assembly (1), the front expansion beam (6), the rear expansion beam (7), the left side beam (9) and the right side beam (10) are provided with a back type buffer frame (11). The glue (3) is a structural glue; And / or, the electric core surface of the electric core assembly (1) is connected with a current collector connecting piece. The current collector connecting piece is fixed on the electric core surface by laser welding. It comprises an electric core assembly (1) and a battery bottom upper layer plate (2), the electric core assembly (1) and the battery bottom upper layer plate (2) are fixed by glue (3). The electric core assembly (1) and the battery bottom upper layer plate (2) are further provided with a bottom buffer pad (5). One end of the electric core assembly (1) is provided with a front expansion beam (6), and the other end is provided with a rear expansion beam (7). The electric core assembly (1), the front expansion beam (6) and the rear expansion beam (7) are fixed together by a connecting piece (8). One side of the electric core assembly (1) is provided with a left side beam (9), and the other side is provided with a right side beam (10). The electric core assembly (1), the front expansion beam (6), the rear expansion beam (7), the left side beam (9) and the right side beam (10) are provided with a back type buffer frame (11). The glue (3) is a structural glue; And / or, the

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