Vehicle structure

Abstract

A vehicle structure capable of further increasing the disassembly difficulty of a vehicle body structural member on which a frame number is engraved. A seat cross member on which a frame number is engraved is connected to a side sill via a connecting stiffener. The side sill is fastened to the connecting stiffener by a regular bolt. The seat cross member is fastened to the connecting stiffener by a broken bolt. Battery packs are provided on the lower side of the seat cross member and are fastened by regular bolts. Thus, a structure can be achieved in which the disassembly difficulty of the vehicle body structural member (seat cross member) on which the frame number is displayed is increased while the replacement work of the battery packs is easily performed.

Description

Technical Field

[0001] This invention relates to a vehicle structure. In particular, this invention relates to a countermeasure to increase the difficulty of disassembling vehicle body structural components engraved with vehicle identification numbers (VINs). Background Technology

[0002] In vehicles, the vehicle identification number (VIN) is assigned as a unique identification number (a unique identification number assigned to each vehicle by the Ministry of Land, Infrastructure, Transport and Tourism). Furthermore, this VIN is typically engraved (stamped) directly onto the vehicle's structural components. Moreover, as disclosed in Patent Document 1, the VIN is engraved on the surface of a major part of the vehicle in a location that is easily identifiable and unlikely to be subject to external damage or corrosion.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2005-119458

[0004] Patent Document 2: US Patent No. 11130536 Summary of the Invention

[0005] In vehicle body structural components (e.g., beam components) bearing the vehicle identification number (VIN), disassembly from the vehicle is required to be significantly more difficult than that of other vehicle body structural components. This is because it is necessary to prevent the misuse of VIN-marked vehicle body structural components by disassembling them and replacing them with other vehicles (e.g., stolen vehicles). Furthermore, to further enhance the deterrent effect against such misuse, a vehicle structure with greater disassembly difficulty than previous structures is required.

[0006] Furthermore, regarding the location of the vehicle identification number (VIN), as disclosed in Patent Document 2, the location of the VIN has not been fully studied for structures where the vehicle is manufactured in modules (e.g., the front or rear modules are integrally formed by aluminum die casting) and the modules are assembled with the door sill beams, etc.

[0007] Furthermore, the high requirements for vehicle body structural components with chassis numbers and the difficulty of disassembly exist in vehicle structures such as those disclosed in Patent Document 2 or in conventional vehicle structures (vehicle structures formed by integrally joining multiple frame materials through welding or bolting).

[0008] The present invention was made in view of this, and its object is to provide a vehicle structure that can further improve the difficulty of disassembling vehicle body structural components engraved with chassis numbers.

[0009] The present invention, which aims to achieve the aforementioned objective, is based on a vehicle structure comprising a pair of left and right side beams, a crossbeam, and fastening components. Furthermore, in this vehicle structure, each side beam is connected to the crossbeam via the fastening components, the crossbeam displays the vehicle identification number (VIN), and the crossbeam is fastened to the fastening components using broken bolts.

[0010] The phrase "the chassis number is displayed on the crossbeam" as used here includes various display states such as the chassis number being engraved on the surface of the crossbeam or the chassis number being installed on a plate.

[0011] According to the specific details, the crossbeam and fastening components are secured by broken-head bolts whose heads are removed during these fastening operations. Since the broken-head bolts are difficult to loosen easily, the difficulty of disassembling the crossbeam is increased. This further increases the difficulty of disassembling the body structure components displaying the chassis number.

[0012] Furthermore, the method of joining the side beam and the fastening component includes bonding.

[0013] Therefore, the bonding strength between the side beam and the fastener can be increased, thereby increasing the difficulty of removing the fastener from the side beam. As a result, even when the crossbeam and the fastener are removed from the vehicle as a single unit, the difficulty of removal is increased, which in turn further increases the difficulty of removing body structure components displaying the vehicle identification number.

[0014] Furthermore, at least the joint portion of the side beam that connects with the crossbeam is made of an alloy containing aluminum or aluminum, and the crossbeam is made of an alloy containing iron or iron.

[0015] Thus, when the side beams and crossbeams are made of dissimilar metals, it is difficult to join them by welding. However, based on the structure that utilizes the aforementioned fastening components, even if the side beams and crossbeams are made of dissimilar metals, they can be assembled as a single unit, and the aforementioned effect can be achieved (further improving the difficulty of disassembling the vehicle body structural components displaying the chassis number).

[0016] Furthermore, a battery is provided on the underside of the crossbeam.

[0017] Therefore, the battery is located in a relatively wide space under the crossbeam, which allows for the battery to be made larger.

[0018] Furthermore, the crossbeam is fastened to the battery by conventional bolts having heads that do not detach from the threaded portion when fastened.

[0019] Therefore, by loosening the bolts (conventional bolts), the battery can be relatively easily removed from the crossbeam, facilitating battery replacement. In other words, a structure can be achieved that simultaneously increases the difficulty of removing the crossbeam (a vehicle body structural component displaying the VIN) while making battery replacement easier.

[0020] Invention Effects

[0021] In this invention, the crossbeam displaying the vehicle identification number (VIN) is connected to each side beam via fastening components, and the crossbeam is secured to the fastening components using broken bolts. This further increases the difficulty of disassembling the vehicle body structural component (crossbeam) displaying the VIN. Attached Figure Description

[0022] Figure 1 This is a perspective view showing the vehicle structure involved in the implementation method.

[0023] Figure 2 This is a perspective view showing a part of the vehicle structure used to illustrate the fastening operations of the side beams, seat crossbeams, connecting stiffening plates, and battery pack.

[0024] Figure 3 This is a three-dimensional view showing the connecting stiffening plate.

[0025] Figure 4 This is a 3D diagram showing a broken bolt.

[0026] Figure 5 It is a perspective view showing a part of the vehicle structure with the side beams, seat crossbeams, connecting stiffening plates, and battery pack secured. Detailed Implementation

[0027] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. This description pertains to vehicle structures used in electric vehicles. Furthermore, the vehicle structures described herein are not limited to electric vehicles, but can also be applied to conventional vehicles (vehicles equipped only with an engine as a driving force source), hybrid electric vehicles, plug-in hybrid electric vehicles, and fuel cell vehicles.

[0028] -Vehicle Structure-

[0029] Figure 1 This is a perspective view showing the vehicle structure 1 involved in this embodiment. Figure 1 In the diagram, arrow FR indicates the forward direction of the vehicle, arrow UP indicates the upward direction, and arrow LH indicates the left side in the vehicle width direction. For example... Figure 1 As shown, the vehicle structure 1 involved in this embodiment includes a front lower module 2, a rear lower module 3 and a battery frame 4, which are integrated into a single assembly.

[0030] Specifically, the battery frame 4 has a front lower module 2 assembled at its rear end, and a rear lower module 3 assembled at its rear end. The specific assembly structure will be described later.

[0031] Furthermore, a battery pack (the battery as described in this invention) 5 is supported on the lower side of the battery frame 4. This battery pack provides power to the motor (not shown) that serves as the driving force source for the vehicle (electric vehicle). The battery pack 5 is a known structure in which a battery module is housed within a battery casing.

[0032] The front lower module 2 and the rear lower module 3 are respectively formed by so-called one-piece die casting (also known as Giga Casting). One-piece die casting is a processing technology for forming large parts made of die-cast aluminum. In this embodiment, instead of the conventional method of assembling multiple parts (e.g., stamped parts) into one piece to form a part of the vehicle body (the front lower part or the rear lower part of the vehicle) by welding or bolting, the front lower module 2 and the rear lower module 3 are formed using a large die casting machine.

[0033] The front lower module 2, which is formed by one-piece die casting, is a structure in which all parts of the front lower part of a conventional vehicle structure are integrally formed, including front side beams 21, 21, suspension tower covers 22, 22, wheel arch inner side 23, and front crossbeams 24. However, the structure of the front lower module 2 is not limited to this.

[0034] Furthermore, the front lower module 2 extends rearward to become the front side beams 21, 21, and its rear end is fixed (connected) to the rear end connection 25, 25 of the front end of the side beams 41, 41 (described later) in the battery frame 4 by bolts.

[0035] Furthermore, the rear lower module 3, which is integrally die-cast, is also a structure that integrally forms the various parts of the rear lower part in conventional vehicle structures, including the rear side beams 31, 31, the rear crossbeam 32, the suspension tower cover 33, the inner wheel arches 34, 34, and the rear floor panel 35. However, the structure of the rear lower module 3 is not limited to this.

[0036] Furthermore, the rear lower module 3 extends forward as the rear side beams 31, 31, and its front end is fastened to the front end connection part 36, 36 of the rear end part of the side beams 41, 41 (described later) in the battery frame 4 by bolts.

[0037] The battery frame 4 is frame-shaped and includes a pair of left and right side beams (sill beams) 41, 41, a front crossbeam 42 that extends along the vehicle width direction and connects the front ends of each side beam 41, 41 to each other, and a rear crossbeam 43 that extends along the vehicle width direction and connects the rear ends of each side beam 41, 41 to each other.

[0038] Side beams 41, 42, front crossbeam 42, and rear crossbeam 43 are all rectangular closed-section structures, ensuring high rigidity. Furthermore, side beams 41, 42 are made of an alloy containing aluminum or aluminum itself. However, the materials used to construct side beams 41, 42 are not limited to these.

[0039] As a fastening structure between the front lower module 2 and the battery frame 4, the outer side (outer side in the vehicle width direction) of the rear end connection part 25 of the front lower module 2 coincides with the inner side (inner side in the vehicle width direction) of the side beam 41 in the battery frame 4, and these are fastened together by multiple bolts B1, B1, ... For example, in the side beam 41, which is composed of a rectangular closed cross-section structure, the outer wall portion (the wall portion located on the outside in the vehicle width direction) 41a and the inner wall portion (the wall portion located on the inside in the vehicle width direction) extending in a direction orthogonal to the vehicle width direction, the outer wall portion 41a is provided with an opening 41c, 41c, ... larger than the head diameter of the bolt B1, and the inner wall portion is provided with an opening smaller than the head diameter of the bolt B1 (not shown). The head of the bolt B1, which is inserted from the outside in the vehicle width direction into the opening 41c of the outer wall portion 41a, abuts against the inner wall portion 41b. The threaded portion of the bolt B1 is screwed into a nut (not shown) that engages with the inner surface (the inner surface in the vehicle width direction) of the rear end connection portion 25 of the front lower module 2. The rear end connection portion 25 of the front lower module 2 is then fastened to the front end portion of the side beam 41 of the battery frame 4. Furthermore, the fastening structure for the rear end connection 25 of the front lower module 2 and the front end of the side beam 41 of the battery frame 4 is not limited to this.

[0040] Furthermore, the fastening structure between the rear lower module 3 and the battery frame 4 is also the same. The outer side of the front connecting part 36 of the rear lower module 3 coincides with the inner side of the side beam 41 in the battery frame 4. These are fastened together by multiple bolts B2, B2, ... (bolts B2 are inserted from the outside into the opening 41d of the outer wall 41a of the battery frame 4 and fastened). However, the fastening structure between the front connecting part 36 of the rear lower module 3 and the rear end part of the side beam 41 of the battery frame 4 is not limited to this.

[0041] The left and right side beams 41, 41 of the battery frame 4 are connected to each other by two seat crossbeams (crossbeams as referred to in this invention) 6, 7. Specifically, both ends of each seat crossbeam 6, 7 are connected to the side beams 41, 41 via connecting stiffening plates (fastening members as referred to in this invention) 8. The connection structures of each seat crossbeam 6, 7 with respect to the side beam 41 are identical; therefore, the connection structure of one end of a seat crossbeam 6 with respect to the side beam 41 will be described here. In addition, each seat crossbeam 6, 7 is made of an alloy containing iron or iron. The materials used to construct each seat crossbeam 6, 7 are not limited to these.

[0042] Figure 2 This is a perspective view of a part of the vehicle structure 1 used to illustrate the fastening operation of the side beam 41, seat crossbeam 6, connecting stiffening plate 8 and battery pack 5 (the operation of connecting the right end of the seat crossbeam 6 in the vehicle width direction to the side beam 41 via the connecting stiffening plate 8).

[0043] like Figure 2 As shown, at the mounting location of the seat crossbeam 6 in the side beam 41, two bolt insertion holes 41f and 41f are formed through the top plate 41e at two locations. Furthermore, at the mounting location of the seat crossbeam 6 in the side beam 41, two bolt insertion holes 41g and 41g are formed through the inner wall portion 41b at two locations. These bolt insertion holes 41f, 41f, 41g, and 41g are for fastening the stiffening plate 8. Additionally, in... Figure 2 In this case, compared to the spacing between the bolt insertion holes 41f, 41f formed through the top plate 41e, the spacing between the bolt insertion holes 41g, 41g formed through the inner wall portion 41b is set to be larger, but is not limited to this. Furthermore, double-sided adhesive tape 41h is attached between the bolt insertion holes 41f, 41f formed on the upper surface of the top plate 41e.

[0044] The seat crossbeam 6 is constructed with a closed rectangular cross-section or a rectangular cross-section with an open lower section. The length of the seat crossbeam 6 is set to be the same as or slightly shorter than the spacing between the pair of side beams 41, 41. The vehicle identification number (VN) is engraved on the upper surface of the top plate 61 of the seat crossbeam 6, serving as an inherent identification number for the vehicle. In this embodiment, the oxide film (also called black film) on the upper surface of the top plate 61 of the seat crossbeam 6 is not removed, and the VN is engraved. Furthermore, the VN is engraved only on one of the two seat crossbeams 6, 7. In this embodiment, the VN is engraved on the front seat crossbeam 6 located in the vehicle's longitudinal direction. Transparent tape 64 is affixed to the upper surface of the top plate 61 of the seat crossbeam 6 at the location where the VN is engraved, covering the VN. This is because, in order to prevent water (rainwater, etc.) from flowing into the engraved part of the chassis number VN and causing corrosion on the upper surface of the top plate 61, the chassis number VN becomes unclear.

[0045] Furthermore, bolt insertion holes 62, 62, and 63 are formed through multiple locations on the top plate 61 of the seat crossbeam 6. Of these bolt insertion holes 62, 62, and 63, the two bolt insertion holes 62 and 62 located on the outer side in the vehicle width direction are for fastening the stiffening plate 8, while the bolt insertion hole 63 located on the inner side in the vehicle width direction is for supporting the battery pack 5. Figure 2 Only one location is shown as the formation position of the bolt insertion hole 63, but the bolt insertion hole 63 is formed in multiple locations on the top plate 61 of the seat beam 6.

[0046] Figure 3 This is a perspective view showing the connecting stiffening plate 8. For example... Figure 2 and Figure 3 As shown, the connecting stiffening plate 8 is a component that connects the side beam 41 and the seat crossbeam 6 by being fastened to the side beam 41 and the seat crossbeam 6 respectively by bolts (see reference). Figure 5 ).

[0047] The connecting stiffening plate 8 includes: a first horizontal portion 81, which overlaps with the upper surface of the top plate 41e of the side beam 41; a vertical portion 82, which overlaps with the inner side surface (the inner side facing the vehicle width direction) of the inner side wall portion 41b of the side beam 41; a second horizontal portion 83, which overlaps with the upper surface of the top plate 61 of the seat crossbeam 6; and a front vertical portion 84, which overlaps with the front plate 65 of the seat crossbeam 6 (see reference). Figure 2 The front surface of the seat beam 6 coincides with the rear surface of the seat beam 6; and the rear vertical portion 85 coincides with the rear surface of the rear plate 66 of the seat beam 6.

[0048] The first horizontal section 81 is composed of a generally rectangular plate. At two locations in the first horizontal section 81 (near the two ends in the vehicle's longitudinal direction), bolt insertion holes 81a and 81a corresponding to the bolt insertion holes 41f and 41f of the side beam 41 are formed through.

[0049] The vertical portion 82 is formed by bending downward from the end of the first horizontal portion 81 located on the inner side in the vehicle width direction. The two sides of the vertical portion 82 in the vehicle front-rear direction have downwardly extending lower portions 82a, 82a, and bolt insertion holes 82b, 82b corresponding to the bolt insertion holes 41g, 41g of the side beam 41 are respectively formed through the lower portions 82a, 82a.

[0050] The second horizontal portion 83 is formed by extending a predetermined dimension from the lower end of the vertical portion 82 inward in the vehicle width direction. At two locations in this second horizontal portion 83 (two locations at a predetermined interval in the vehicle longitudinal direction), bolt insertion holes 83a and 83a corresponding to the bolt insertion holes 62 and 62 of the seat crossbeam 6 are formed through.

[0051] The spacing between the front vertical portion 84 and the rear vertical portion 85 is approximately the same as the width of the seat crossbeam 6 in the vehicle's longitudinal direction. That is, the space enclosed by the second horizontal portion 83, the front vertical portion 84, and the rear vertical portion 85 forms an embedding space that is approximately consistent with the side view shape (cross-sectional shape) of the seat crossbeam 6. Therefore, with the second horizontal portion 83 overlapping the upper surface of the top plate 61 of the seat crossbeam 6, the front vertical portion 84 abuts against the front surface of the front plate 65 of the seat crossbeam 6, and the rear vertical portion 85 abuts against the rear surface of the rear plate 66 of the seat crossbeam 6, forming a structure that clamps the seat crossbeam 6 between these front vertical portions 84 and rear vertical portions 85 (see reference). Figure 5 ).

[0052] As a feature of this embodiment, different types of bolts are used for the bolts that fasten the stiffening plate 8 to the side beam 41 and the bolts that fasten the stiffening plate 8 to the seat crossbeam 6.

[0053] Specifically, to fasten the connecting cover 8 to the side beam 41, commonly used bolts, namely bolts B3, B3 and B4, B4, which have a head and a threaded portion and whose head does not detach from the threaded portion when tightened, are used. Bolts B3 and B3 are inserted from the bolt insertion hole 81a of the connecting cover 8 to the bolt insertion hole 41f of the side beam 41, and bolts B4 and B4 are inserted from the bolt insertion hole 82b of the connecting cover 8 to the bolt insertion hole 41g of the side beam 41. Furthermore, to support the battery pack 5 on the seat crossbeam 6, commonly used bolts, namely bolts B5, which have a head and a threaded portion and whose head does not detach from the threaded portion when tightened, are also used. Bolt B5 is inserted from the bolt insertion hole 63 of the seat crossbeam 6 to the battery pack 5 (e.g., a bracket located on the upper part of the battery pack 5).

[0054] In contrast, a broken-head bolt 9 is used as the bolt that is inserted from the bolt insertion hole 83a of the connecting stiffening plate 8 to the bolt insertion hole 62 of the seat crossbeam 6 in order to fasten the connecting stiffening plate 8 to the seat crossbeam 6.

[0055] Figure 4 This is a perspective view of the broken head bolt 9. The broken head bolt 9 has a shaft portion 91, a flange portion 92, and a head 93. The shaft portion 91 has external threads formed on its outer circumferential surface. The flange portion 92 is continuous with one end of the shaft portion 91 and has a generally frustum-shaped outer diameter that increases towards the shaft portion 91. The head 93 is continuous with one end of the flange portion 92 (the side with the smaller outer diameter) and has a generally hexagonal prism shape. This head 93 is the part for installing tools (wrench, etc.) when screwing in the broken head bolt 9 (when tightening the connecting stiffening plate 8 to the seat crossbeam 6). Due to this structure, when the broken head bolt 9 is tightened to the connecting stiffening plate 8 to the seat crossbeam 6, a greater torque is applied to the head 93 after tightening, thereby causing the clamping portion 94 between the head 93 and the flange portion 92 to break, the head 93 to be removed, and thus it is difficult to loosen.

[0056] Assembly work-

[0057] Next, the assembly process of securing the side beam 41, seat crossbeam 6, connecting stiffening plate 8, and battery pack 5 together will be described. This assembly of components 41, 6, 8, and 5 is performed after the rear end of the front lower module 2 is assembled to the front end of the battery frame 4, and the front end of the rear lower module 3 is assembled to the rear end of the battery frame 4. Furthermore, in this embodiment, the front lower module 2, rear lower module 3, and battery frame 4 are painted as required before assembly. Alternatively, these components 2, 3, and 4 can also be painted after assembly.

[0058] Furthermore, during the assembly process in this embodiment, the required components or equipment may be pre-installed on the front lower module 2. For example, the front bulkhead or cooling system may be pre-installed.

[0059] During the assembly process of securing the side beam 41, seat crossbeam 6, connecting stiffening plate 8, and battery pack 5 together, the battery pack 5 is first assembled integrally with the seat crossbeams 6 and 7. That is, the seat crossbeams 6 and 7 are placed at designated positions on the upper surface of the battery pack 5, and bolts B5 are inserted through bolt holes 63 (formed in multiple locations) in the top plate 61 of the seat crossbeams 6 and 7. These bolts B5 are then screwed into the internal threads of the bracket located on the upper part of the battery pack, thereby assembling the battery pack 5 integrally with the seat crossbeams 6 and 7. However, this assembly structure for the battery pack 5 and seat crossbeams 6 and 7 is not limited to this.

[0060] On the other hand, the connecting stiffening plate 8 is installed on the side beam 41. Specifically, the first horizontal portion 81 of the connecting stiffening plate 8 coincides with the upper surface of the top plate 41e of the side beam 41, and the vertical portion 82 of the connecting stiffening plate 8 coincides with the inner side wall portion 41b of the side beam 41. At this time, the double-sided adhesive tape 41h attached to the upper surface of the top plate 41e of the side beam 41 is bonded to the lower surface of the first horizontal portion 81 of the connecting stiffening plate 8, and the side beam 41 and the connecting stiffening plate 8 are bonded by the double-sided adhesive tape 41h.

[0061] With the various parts of the connecting stiffening plate 8 (the first horizontal part 81 and the vertical part 82) overlapping with the side beam 41, the bolt through holes 81a of the connecting stiffening plate 8 are aligned with the bolt through holes 41f of the side beam 41, and the bolt through holes 82b of the connecting stiffening plate 8 are aligned with the bolt through holes 41g of the side beam 41. Then, the first horizontal part 81 of the stiffening plate 8 is fastened to the top plate 41e of the side beam 41 by bolts B3 passing through the bolt through holes 81a and 41f (with nuts not shown), and the vertical part 82 (drooping part 82a) of the stiffening plate 8 is fastened to the inner wall part 41b of the side beam 41 by bolts B4 passing through the bolt through holes 82b and 41g (with nuts not shown). Thus, the connecting stiffening plate 8 is assembled to the side beam 41.

[0062] Then, the seat crossbeams 6 and 7, which are integrally assembled with the battery pack 5, are fastened to the connecting stiffening plate 8. This fastening operation is described using seat crossbeam 6 as an example, but seat crossbeam 7 is also fastened to the connecting stiffening plate 8 by the same operation.

[0063] The seat crossbeam 6, which is integrally assembled with the battery pack 5, is inserted from the lower side of the battery frame 4 into the inner space of the battery frame 4 (the space between the side beams 41, 41). The seat crossbeam 6 is inserted into the embedded space in the connecting stiffening plate 8 (the space surrounded by the second horizontal part 83, the front vertical part 84, and the rear vertical part 85). That is, the upper surface of the top plate 61 of the seat crossbeam 6 abuts against the lower surface of the second horizontal part 83 of the connecting stiffening plate 8, the front surface of the front plate 65 of the seat crossbeam 6 abuts against the rear surface (the rear side surface in the vehicle longitudinal direction) of the front vertical part 84 of the connecting stiffening plate 8, and the rear surface of the rear plate 66 of the seat crossbeam 6 abuts against the front surface (the front side surface in the vehicle longitudinal direction) of the rear vertical part 85 of the connecting stiffening plate 8. In this state, the bolt insertion hole 83a of the connecting stiffening plate 8 is aligned with the bolt insertion hole 62 of the seat crossbeam 6. Then, by passing the broken bolt 9 through the bolt insertion holes 83a and 62, the seat crossbeam 6 is fastened to the second horizontal part 83 of the connecting stiffening plate 8. Thus, the seat crossbeam 6 is connected to the side beam 41 via the connecting stiffening plate 8.

[0064] Thus, after the seat crossbeam 6 is assembled to the side beam 41 using the broken bolt 9, a greater torque is applied to the head 93 of the broken bolt 9, causing the clamping part 94 of the broken bolt 9 to break and the head 93 to be removed. Therefore, as... Figure 5 As shown, the broken bolt 9 is in a state where it is difficult to loosen.

[0065] Through the above assembly operations, vehicle structure 1 is manufactured, which is an integral assembly of front lower module 2, rear lower module 3, battery frame 4, seat crossbeams 6 and 7, and battery pack 5.

[0066] -Effects of the Implementation Method-

[0067] As explained above, in this embodiment, the seat crossbeam 6 and the connecting stiffening plate 8 are fastened by a broken bolt 9 whose head 93 is removed during these fastening operations. Since the broken bolt 9 is difficult to loosen easily, the difficulty of disassembling the seat crossbeam 6 is increased. This further increases the difficulty of disassembling the vehicle body structural component (seat crossbeam 6) marked with the chassis number VN. As a result, the effect of preventing the disassembly and misuse of the vehicle body structural component marked with the chassis number VN is improved. Furthermore, in this embodiment, by loosening bolt B5 (a conventional bolt), the battery pack 5 can be relatively easily removed from the seat crossbeams 6 and 7, making battery pack 5 replacement easy. That is, a structure can be achieved that simultaneously increases the difficulty of disassembling the seat crossbeam 6 (the vehicle body structural component displaying the chassis number VN) and facilitates battery pack 5 replacement.

[0068] Furthermore, in this embodiment, the side beam 41 is not only fastened to the connecting stiffening plate 8 by bolts B3 and B4, but also bonded by double-sided adhesive tape 41h. Therefore, the bonding strength between the side beam 41 and the connecting stiffening plate 8 can be increased by bonding, thereby increasing the difficulty of disassembling the connecting stiffening plate 8 from the side beam 41. Thus, even when the seat crossbeam 6 and the connecting stiffening plate 8 are removed from the vehicle as a single unit, the difficulty of disassembly is increased, further enhancing the difficulty of disassembling the vehicle body structural component (seat crossbeam 6) displaying the chassis number VN. Additionally, if not only the bolts (broken-head bolts 9) fastening the seat crossbeam 6 and the connecting stiffening plate 8, but also the bolts fastening the side beam 41 and the connecting stiffening plate 8, are also made of broken-head bolts 9, the difficulty of disassembling the seat crossbeam 6 and the connecting stiffening plate 8 as a single unit from the vehicle can be further increased, further enhancing the effect of preventing the vehicle body structural component with the chassis number VN from being disassembled and misused.

[0069] Furthermore, as in this embodiment, when the side beams 41, 41 and the seat crossbeams 6, 7 are made of dissimilar metals, it is difficult to join them by welding. However, according to the structure utilizing the connecting stiffening plate 8, even if the side beams 41, 41 and the seat crossbeams 6, 7 are made of dissimilar metals, they can be assembled as a single unit, and the aforementioned effect (further improving the difficulty of disassembling the vehicle body structural components displaying the chassis number VN) can be achieved.

[0070] Furthermore, in this embodiment, since the battery pack 5 is provided on the lower side of the seat crossbeams 6 and 7, the battery pack 5 can be provided in a relatively wide space on the lower side of the seat crossbeams 6 and 7, thus enabling the battery pack 5 to be made larger.

[0071] -Other implementation methods-

[0072] Furthermore, the present invention is not limited to the described embodiments, and can encompass all variations or applications within the scope of the claims and their equivalents.

[0073] For example, in the described embodiment, two seat crossbeams 6 and 7 are connected to the side beam 41 via a connecting stiffener 8, and a broken-head bolt 9 is used as the fastening method between the seat crossbeams 6 and 7 and the connecting stiffener 8. The invention is not limited to this; the broken-head bolt 9 may also be used only to fasten the seat crossbeam 6 marked with the chassis number VN to the connecting stiffener 8. That is, in the aforementioned embodiment, only the seat crossbeam 6 located on the front side in the vehicle's longitudinal direction is fastened to the connecting stiffener 8 using the broken-head bolt 9. Furthermore, when the portion marked with the chassis number VN is located on the rear side of the seat crossbeam 7 in the vehicle's longitudinal direction, only the seat crossbeam 7 located on the rear side in the vehicle's longitudinal direction is fastened to the connecting stiffener 8 using the broken-head bolt 9.

[0074] Furthermore, in the described embodiment, when the seat crossbeam 6 is fastened to the connecting stiffening plate 8 at two locations, the broken-head bolt 9 is applied at each location. The invention is not limited to this; the broken-head bolt 9 may also be applied at only one location. Furthermore, when the seat crossbeam 6 is fastened to the connecting stiffening plate 8 at three or more locations, the broken-head bolt 9 may be applied at at least one location.

[0075] Furthermore, in the described embodiment, after the battery pack 5 is integrally assembled with the seat crossbeams 6 and 7, the seat crossbeams 6 and 7 are connected to the side beam 41 via the connecting stiffening plate 8. The invention is not limited to this; alternatively, the battery pack 5 can be assembled to the seat crossbeams 6 and 7 after the seat crossbeams 6 and 7 are connected to the side beam 41 via the connecting stiffening plate 8.

[0076] Furthermore, in the described embodiment, the application of the present invention to a vehicle structure 1 employing a front lower module 2 and a rear lower module 3 formed by one-piece die casting has been explained. The present invention is not limited thereto, and can also be applied to conventional vehicle structures constructed by integrally assembling multiple components (e.g., stamped parts) through welding or bolting.

[0077] Furthermore, in the described embodiment, the side beam marked with the chassis number VN is used as the seat crossbeam 6. The invention is not limited to this, and can also be applied to various crossbeams connecting a pair of left and right side beams 41, 41.

[0078] Industrial availability

[0079] This invention is applicable to vehicle structures that use body structure components formed by one-piece die casting.

[0080] Symbol Explanation

[0081] 1-Vehicle structure, 41-Side beam, 41h-Double-sided tape, 5-Battery pack (battery), 6-Seat crossbeam (crossbeam), 8-Connecting stiffening plate (fastening component), 9-Broken bolt, B1~B5-Conventional bolt, VN-Chassis number.

Claims

1. A vehicle structure comprising a pair of left and right side beams, a crossbeam, and fastening components, characterized in that, Each side beam is connected to the cross beam via the fastening component. The chassis number is displayed on the crossbeam. The crossbeam is fastened to the fastening component by a broken bolt.

2. The vehicle structure according to claim 1, characterized in that, Methods for joining the side beam to the fastening component include bonding.

3. The vehicle structure according to claim 1 or 2, characterized in that, At least the joint portion of the side beam that connects with the crossbeam is made of an alloy containing aluminum or aluminum, and the crossbeam is made of an alloy containing iron or iron.

4. The vehicle structure according to claim 1 or 2, characterized in that, A battery is installed on the underside of the crossbeam.

5. The vehicle structure according to claim 4, characterized in that, The crossbeam is fastened to the battery by conventional bolts having heads that do not detach from the threads when tightened.

Images